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TABLE OF CONTENTS exec.library/AbortIO exec.library/AddDevice exec.library/AddHead exec.library/AddIntServer exec.library/AddLibrary exec.library/AddMemHandler exec.library/AddMemList exec.library/AddPort exec.library/AddResource exec.library/AddSemaphore exec.library/AddTail exec.library/AddTask exec.library/Alert exec.library/AllocAbs exec.library/Allocate exec.library/AllocEntry exec.library/AllocMem exec.library/AllocPooled exec.library/AllocSignal exec.library/AllocTrap exec.library/AllocVec exec.library/AttemptSemaphore exec.library/AttemptSemaphoreShared exec.library/AvailMem exec.library/CacheClearE exec.library/CacheClearU exec.library/CacheControl exec.library/CachePostDMA exec.library/CachePreDMA exec.library/Cause exec.library/CheckIO exec.library/CloseDevice exec.library/CloseLibrary exec.library/ColdReboot exec.library/CopyMem exec.library/CopyMemQuick exec.library/CreateIORequest exec.library/CreateMsgPort exec.library/CreatePool exec.library/Deallocate exec.library/Debug exec.library/DeleteIORequest exec.library/DeleteMsgPort exec.library/DeletePool exec.library/Disable exec.library/DoIO exec.library/Enable exec.library/Enqueue exec.library/FindName exec.library/FindPort exec.library/FindResident exec.library/FindSemaphore exec.library/FindTask exec.library/Forbid exec.library/FreeEntry exec.library/FreeMem exec.library/FreePooled exec.library/FreeSignal exec.library/FreeTrap exec.library/FreeVec exec.library/GetCC exec.library/GetMsg exec.library/InitCode exec.library/InitResident exec.library/InitSemaphore exec.library/InitStruct exec.library/Insert exec.library/MakeFunctions exec.library/MakeLibrary exec.library/ObtainQuickVector exec.library/ObtainSemaphore exec.library/ObtainSemaphoreList exec.library/ObtainSemaphoreShared exec.library/OldOpenLibrary exec.library/OpenDevice exec.library/OpenLibrary exec.library/OpenResource exec.library/Permit exec.library/Procure exec.library/PutMsg exec.library/RawDoFmt exec.library/ReleaseSemaphore exec.library/ReleaseSemaphoreList exec.library/RemDevice exec.library/RemHead exec.library/RemIntServer exec.library/RemLibrary exec.library/RemMemHandler exec.library/Remove exec.library/RemPort exec.library/RemResource exec.library/RemSemaphore exec.library/RemTail exec.library/RemTask exec.library/ReplyMsg exec.library/SendIO exec.library/SetExcept exec.library/SetFunction exec.library/SetIntVector exec.library/SetSignal exec.library/SetSR exec.library/SetTaskPri exec.library/Signal exec.library/StackSwap exec.library/SumKickData exec.library/SumLibrary exec.library/SuperState exec.library/Supervisor exec.library/TypeOfMem exec.library/UserState exec.library/Vacate exec.library/Wait exec.library/WaitIO exec.library/WaitPort SAD/--Overview-- SAD/ALLOCATE_MEMORY SAD/CALL_ADDRESS SAD/FREE_MEMORY SAD/GET_CONTEXT_FRAME SAD/NOP SAD/READ_ARRAY SAD/READ_BYTE SAD/READ_LONG SAD/READ_WORD SAD/RESET SAD/RETURN_TO_SYSTEM SAD/TURN_OFF_SINGLE SAD/TURN_ON_SINGLE SAD/WRITE_ARRAY SAD/WRITE_BYTE SAD/WRITE_LONG SAD/WRITE_WORD exec.library/AbortIO exec.library/AbortIO NAME AbortIO - attempt to abort an in-progress I/O request SYNOPSIS AbortIO(iORequest) A1 VOID AbortIO(struct IORequest *); FUNCTION Ask a device to abort a previously started IORequest. This is done by calling the device's ABORTIO vector, with your given IORequest. AbortIO is a command the device that may or may not grant. If successful, the device will stop processing the IORequest, and reply to it earlier than it would otherwise have done. NOTE AbortIO() does NOT Remove() the IORequest from your ReplyPort, OR wait for it to complete. After an AbortIO() you must wait normally for the reply message before actually reusing the request. If a request has already completed when AbortIO() is called, no action is taken. EXAMPLE AbortIO(timer_request); WaitIO(timer_request); /* Message is free to be reused */ INPUTS iORequest - pointer to an I/O request block (must have been used at least once. May be active or finished). SEE ALSO WaitIO, DoIO, SendIO, CheckIO exec.library/AddDevice exec.library/AddDevice NAME AddDevice -- add a device to the system SYNOPSIS AddDevice(device) A1 void AddDevice(struct Device *); FUNCTION This function adds a new device to the system device list, making it available to other programs. The device must be ready to be opened at this time. INPUTS device - pointer to a properly initialized device node SEE ALSO RemDevice, OpenDevice, CloseDevice, MakeLibrary exec.library/AddHead exec.library/AddHead NAME AddHead -- insert node at the head of a list SYNOPSIS AddHead(list, node) A0 A1 void AddHead(struct List *, struct Node *) FUNCTION Add a node to the head of a doubly linked list. Assembly programmers may prefer to use the ADDHEAD macro from "exec/lists.i". WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS list - a pointer to the target list header node - the node to insert at head SEE ALSO AddTail, Enqueue, Insert, Remove, RemHead, RemTail exec.library/AddIntServer exec.library/AddIntServer NAME AddIntServer -- add an interrupt server to a system server chain SYNOPSIS AddIntServer(intNum, interrupt) D0-0:4 A1 void AddIntServer(ULONG, struct Interrupt *); FUNCTION This function adds a new interrupt server to a given server chain. The node is located on the chain in a priority dependent position. If this is the first server on a particular chain, interrupts will be enabled for that chain. Each link in the chain will be called in priority order until the chain ends or one of the servers returns with the 68000's Z condition code clear (indicating non-zero). Servers on the chain should return with the Z flag clear if the interrupt was specifically for that server, and no one else. VERTB servers should always return Z set. (Take care with High Level Language servers, the language may not have a mechanism for reliably setting the Z flag on exit). Servers are called with the following register conventions: D0 - scratch D1 - scratch A0 - scratch A1 - server is_Data pointer (scratch) A5 - jump vector register (scratch) A6 - scratch all other registers must be preserved INPUTS intNum - the Paula interrupt bit number (0 through 14). Processor level seven interrupts (NMI) are encoded as intNum 15. The PORTS, COPER, VERTB, EXTER and NMI interrupts are set up as server chains. interrupt - pointer to an Interrupt structure. By convention, the LN_NAME of the interrupt structure must point a descriptive string so that other users may identify who currently has control of the interrupt. WARNING Some compilers or assemblers may optimize code in unexpected ways, affecting the conditions codes returned from the function. Watch out for a "MOVEM" instruction (which does not affect the condition codes) turning into "MOVE" (which does). BUGS The graphics library's VBLANK server, and some user code, currently assume that address register A0 will contain a pointer to the custom chips. If you add a server at a priority of 10 or greater, you must compensate for this by providing the expected value ($DFF000). SEE ALSO RemIntServer, SetIntVector, hardware/intbits.i,exec/interrupts.i exec.library/AddLibrary exec.library/AddLibrary NAME AddLibrary -- add a library to the system SYNOPSIS AddLibrary(library) A1 void AddLibrary(struct Library *); FUNCTION This function adds a new library to the system, making it available to other programs. The library should be ready to be opened at this time. It will be added to the system library name list, and the checksum on the library entries will be calculated. INPUTS library - pointer to a properly initialized library structure SEE ALSO RemLibrary, CloseLibrary, OpenLibrary, MakeLibrary exec.library/AddMemHandler exec.library/AddMemHandler NAME AddMemHandler - Add a low memory handler to exec (V39) SYNOPSIS AddMemHandler(memHandler) A1 VOID AddMemHandler(struct Interrupt *); FUNCTION This function adds a low memory handler to the system. The handler is described in the Interrupt structure. Due to multitasking issues, the handler must be ready to run the moment this function call is made. (The handler may be called before the call returns) NOTE Adding a handler from within a handler will cause undefined actions. It is safe to add a handler to the list while within a handler but the newly added handler may or may not be called for the specific failure currently running. EXAMPLE struct Interrupt *myInt; /* Assume it is allocated */ myInt->is_Node.ln_Pri=50; /* Relatively early; before RAMLIB */ /* Please fill in the name field! */ myInt->is_Node.ln_Name="Example Handler"; myInt->is_Data=(APTR)mydata_pointer; myInt->is_Code=myhandler_code; AddMemHandler(myInt); ... /* and so on */ _myhandler_code: ; This is the handler code ; We are passed a pointer to struct MemHandlerData ; in a0, the value of is_Data in a1 and ; ExecBase in a6. ; We must not break forbid!!! ; ; Start off assuming we did nothing ; moveq.l #MEM_DID_NOTHING,d0 move.l memh_RequestFlags(a0),d1 btst.l #MEMB_CHIP,d1 ; Did the failure happen in CHIP beq.s handler_nop ; If not, we have nothing to do bsr DoMyMagic ; Do the magic... ; DoMyMagic frees whatever we can and returns d0 set... handler_nop: rts ; Return with d0 set... INPUTS memHandler - A pointer to a completely filled in Interrupt structure The priority field determine the position of the handler with respect to other handlers in the system. The higher the priority, the earlier the handler is called. Positive priorities will have the handler called before any of the library expunge vectors are called. Negative priority handlers will be called after the library expunge routines are called. (Note: RAMLIB is a handler at priority 0) SEE ALSO RemMemHandler, exec/interrupts.i exec.library/AddMemList exec.library/AddMemList NAME AddMemList - add memory to the system free pool SYNOPSIS AddMemList( size, attributes, pri, base, name ) D0 D1 D2 A0 A1 void AddMemList(ULONG, ULONG, LONG, APTR, STRPTR); FUNCTION Add a new region of memory to the system free pool. The first few bytes will be used to hold the MemHeader structure. The remainder will be made available to the rest of the world. INPUTS size - the size (in bytes) of the memory area attributes - the attributes word that the memory pool will have pri - the priority for this memory. CHIP memory has a pri of -10, 16 bit expansion memory has a priority of 0. The higher the priority, the closer to the head of the memory list it will be placed. base - the base of the new memory area name - the name that will be used in the memory header, or NULL if no name is to be provided. This name is not copied, so it must remain valid for as long as the memory header is in the system. NOTES *DO NOT* add memory to the system with the attribute of MEMF_KICK. EXEC will mark your memory as such if it is of the right type. SEE ALSO AllocMem, exec/memory.h exec.library/AddPort exec.library/AddPort NAME AddPort -- add a public message port to the system SYNOPSIS AddPort(port) A1 void AddPort(struct MsgPort *); FUNCTION This function attaches a message port structure to the system's public message port list, where it can be found by the FindPort() function. The name and priority fields of the port structure must be initialized prior to calling this function. If the user does not require the priority field, it should be initialized to zero. Only ports that will be searched for with FindPort() need to be added to the system list. In addition, adding ports is often useful during debugging. If the port will be searched for, the priority field should be at least 1 (to avoid the large number of inactive ports at priority zero). If the port will be searched for often, set the priority in the 50-100 range (so it will be before other less used ports). Once a port has been added to the naming list, you must be careful to remove the port from the list (via RemPort) before deallocating its memory. NOTE A point of confusion is that clearing a MsgPort structure to all zeros is not enough to prepare it for use. As mentioned in the Exec chapter of the ROM Kernel Manual, the List for the MsgPort must be initialized. This is automatically handled by AddPort(), and amiga.lib/CreatePort. This initialization can be done manually with amiga.lib/NewList or the assembly NEWLIST macro. Do not AddPort an active port. INPUTS port - pointer to a message port SEE ALSO RemPort, FindPort, amiga.lib/CreatePort, amiga.lib/NewList exec.library/AddResource exec.library/AddResource NAME AddResource -- add a resource to the system SYNOPSIS AddResource(resource) A1 void AddResource(APTR); FUNCTION This function adds a new resource to the system and makes it available to other users. The resource must be ready to be called at this time. Resources currently have no system-imposed structure, however they must start with a standard named node (LN_SIZE), and should with a standard Library node (LIB_SIZE). INPUTS resource - pointer an initialized resource node SEE ALSO RemResource, OpenResource, MakeLibrary exec.library/AddSemaphore exec.library/AddSemaphore NAME AddSemaphore -- initialize then add a signal semaphore to the system SYNOPSIS AddSemaphore(signalSemaphore) A1 void AddSemaphore(struct SignalSemaphore *); FUNCTION This function attaches a signal semaphore structure to the system's public signal semaphore list. The name and priority fields of the semaphore structure must be initialized prior to calling this function. If you do not want to let others rendezvous with this semaphore, use InitSemaphore() instead. If a semaphore has been added to the naming list, you must be careful to remove the semaphore from the list (via RemSemaphore) before deallocating its memory. Semaphores that are linked together in an allocation list (which ObtainSemaphoreList() would use) may not be added to the system naming list, because the facilities use the link field of the signal semaphore in incompatible ways INPUTS signalSemaphore -- an signal semaphore structure BUGS Does not work in Exec <V36. Instead use this code: #include <exec/execbase.h> #include <exec/nodes.h> extern struct ExecBase *SysBase; ... void LocalAddSemaphore(s) struct SignalSemaphore *s; { s->ss_Link.ln_Type=NT_SIGNALSEM; InitSemaphore(s); Forbid(); Enqueue(&SysBase->SemaphoreList,s); Permit(); } SEE ALSO RemSemaphore, FindSemaphore, InitSemaphore exec.library/AddTail exec.library/AddTail NAME AddTail -- append node to tail of a list SYNOPSIS AddTail(list, node) A0 A1 void AddTail(struct List *, struct Node *); FUNCTION Add a node to the tail of a doubly linked list. Assembly programmers may prefer to use the ADDTAIL macro from "exec/lists.i". WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS list - a pointer to the target list header node - a pointer to the node to insert at tail of the list SEE ALSO AddHead, Enqueue, Insert, Remove, RemHead, RemTail exec.library/AddTask exec.library/AddTask NAME AddTask -- add a task to the system SYNOPSIS AddTask(task, initialPC, finalPC) A1 A2 A3 APTR AddTask(struct Task *, APTR, APTR); FUNCTION Add a task to the system. A reschedule will be run; the task with the highest priority in the system will start to execute (this may or may not be the new task). Certain fields of the task control block must be initialized and a stack allocated prior to calling this function. The absolute smallest stack that is allowable is something in the range of 100 bytes, but in general the stack size is dependent on what subsystems are called. In general 256 bytes is sufficient if only Exec is called, and 4K will do if anything in the system is called. DO NOT UNDERESTIMATE. If you use a stack sniffing utility, leave a healthy pad above the minimum value. The system guarantees that its stack operations will leave the stack longword aligned. This function will temporarily use space from the new task's stack for the task's initial set of registers. This space is allocated starting at the SPREG location specified in the task control block (not from SPUPPER). This means that a task's stack may contain static data put there prior to its execution. This is useful for providing initialized global variables or some tasks may want to use this space for passing the task its initial arguments. A task's initial registers are set to zero (except the PC). The TC_MEMENTRY field of the task structure may be extended by the user to hold additional MemLists (as returned by AllocEntry()). These will be automatically be deallocated at RemTask() time. If the code you have used to start the task has already added something to the MEMENTRY list, simply use AddHead to add your new MemLists in. If no initialization has been done, a NewList will need to be performed. INPUTS task - pointer to the task control block (TCB). All unset fields must be zero. initialPC - the initial entry point's address finalPC - the finalization code entry point's address. If zero, the system will use a general finalizer. This pointer is placed on the stack as if it were the outermost return address. RESULTS For V36, AddTask returns either a NULL or the address of the new task. Old code need not check this. WARNING Tasks are a low-level building block, and are unable to call dos.library, or any system function that might call dos.library. See the AmigaDOS CreateProc() for information on Processes. SEE ALSO RemTask, FindTask, amiga.lib/CreateTask, dos/CreateProc, amiga.lib/NewList exec.library/Alert exec.library/Alert NAME Alert -- alert the user of an error SYNOPSIS Alert(alertNum) D7 void Alert(ULONG); FUNCTION Alerts the user of a serious system problem. This function will bring the system to a grinding halt, and do whatever is necessary to present the user with a message stating what happened. Interrupts are disabled, and an attempt to post the alert is made. If that fails, the system is reset. When the system comes up again, Exec notices the cause of the failure and tries again to post the alert. If the Alert is a recoverable type, this call MAY return. This call may be made at any time, including interrupts. (Well, only in interrupts if it is non-recoverable) New, for V39: The alert now times out based on the value in LastAlert[3] This value is transfered accross warm-reboots and thus will let you set it once. The value is the number of frames that need to be displayed before the alert is auto-answered. A value of 0 will thus make the alert never be displayed. Note that it is recommended that applications *NOT* change the value in LastAlert[] since the main reason for this is to make unattended operation of the Amiga (in production enviroments) possible. POST-MORTEM DIAGNOSIS There are several options for determining the cause of a crash. Descriptions of each alert number can be found in the "alerts.h" include file. A remote terminal can be attached to the Amiga's first built-in serial port. Set the communication parameters to 9600 baud, 8 bits, no parity. Before resetting the machine, the Alert function will blink the power LED 10 times. While the power indicator is flashing, pressing DELETE on the remote terminal will invoke the ROM debugger. INPUT alertNum - a number indicating the particular alert. -1 is not a valid input. NOTE Much more needs to be said about this function and its implications. SEE ALSO exec/alerts.h exec.library/AllocAbs exec.library/AllocAbs NAME AllocAbs -- allocate at a given location SYNOPSIS memoryBlock = AllocAbs(byteSize, location) D0 D0 A1 void *AllocAbs(ULONG, APTR); FUNCTION This function attempts to allocate memory at a given absolute memory location. Often this is used by boot-surviving entities such as recoverable ram-disks. If the memory is already being used, or if there is not enough memory to satisfy the request, AllocAbs will return NULL. This block may not be exactly the same as the requested block because of rounding, but if the return value is non-zero, the block is guaranteed to contain the requested range. INPUTS byteSize - the size of the desired block in bytes This number is rounded up to the next larger block size for the actual allocation. location - the address where the memory MUST be. RESULT memoryBlock - a pointer to the newly allocated memory block, or NULL if failed. NOTE If the free list is corrupt, the system will panic with alert AN_MemCorrupt, $01000005. The 8 bytes past the end of an AllocAbs will be changed by Exec relinking the next block of memory. Generally you can't trust the first 8 bytes of anything you AllocAbs. SEE ALSO AllocMem, FreeMem exec.library/Allocate exec.library/Allocate NAME Allocate - allocate a block of memory SYNOPSIS memoryBlock=Allocate(memHeader, byteSize) D0 A0 D0 void *Allocate(struct MemHeader *, ULONG); FUNCTION This function is used to allocate blocks of memory from a given private free memory pool (as specified by a MemHeader and its memory chunk list). Allocate will return the first free block that is greater than or equal to the requested size. All blocks, whether free or allocated, will be block aligned; hence, all allocation sizes are rounded up to the next block even value (e.g. the minimum allocation resolution is currently 8 bytes. A request for 8 bytes will use up exactly 8 bytes. A request for 7 bytes will also use up exactly 8 bytes.). This function can be used to manage an application's internal data memory. Note that no arbitration of the MemHeader and associated free chunk list is done. You must be the owner before calling Allocate. INPUTS memHeader - points to the local memory list header. byteSize - the size of the desired block in bytes. RESULT memoryBlock - a pointer to the just allocated free block. If there are no free regions large enough to satisfy the request, return zero. EXAMPLE #include <exec/types.h> #include <exec/memory.h> void *AllocMem(); #define BLOCKSIZE 4096L /* Or whatever you want */ void main() { struct MemHeader *mh; struct MemChunk *mc; APTR block1; APTR block2; /* Get the MemHeader needed to keep track of our new block */ mh = (struct MemHeader *) AllocMem((long)sizeof(struct MemHeader), MEMF_CLEAR ); if( !mh ) exit(10); /* Get the actual block the above MemHeader will manage */ mc = (struct MemChunk *)AllocMem( BLOCKSIZE, 0L ); if( !mc ) { FreeMem( mh, (long)sizeof(struct MemHeader) ); exit(10); } mh->mh_Node.ln_Type = NT_MEMORY; mh->mh_Node.ln_Name = "myname"; mh->mh_First = mc; mh->mh_Lower = (APTR) mc; mh->mh_Upper = (APTR) ( BLOCKSIZE + (ULONG) mc ); mh->mh_Free = BLOCKSIZE; /* Set up first chunk in the freelist */ mc->mc_Next = NULL; mc->mc_Bytes = BLOCKSIZE; block1 = (APTR) Allocate( mh, 20L ); block2 = (APTR) Allocate( mh, 314L ); printf("mh=$%lx mc=$%lx\n",mh,mc); printf("Block1=$%lx, Block2=$%lx\n",block1,block2); FreeMem( mh, (long)sizeof(struct MemHeader) ); FreeMem( mc, BLOCKSIZE ); } NOTE If the free list is corrupt, the system will panic with alert AN_MemCorrupt, $01000005. SEE ALSO Deallocate, exec/memory.h exec.library/AllocEntry exec.library/AllocEntry NAME AllocEntry -- allocate many regions of memory SYNOPSIS memList = AllocEntry(memList) D0 A0 struct MemList *AllocEntry(struct MemList *); FUNCTION This function takes a memList structure and allocates enough memory to hold the required memory as well as a MemList structure to keep track of it. These MemList structures may be linked together in a task control block to keep track of the total memory usage of this task. (See the description of TC_MEMENTRY under RemTask). INPUTS memList -- A MemList structure filled in with MemEntry structures. RESULTS memList -- A different MemList filled in with the actual memory allocated in the me_Addr field, and their sizes in me_Length. If enough memory cannot be obtained, then the requirements of the allocation that failed is returned and bit 31 is set. WARNING: The result is unusual! Bit 31 indicates failure. EXAMPLES The user wants five regions of 2, 4, 8, 16, and 32 bytes in size with requirements of MEMF_CLEAR, MEMF_PUBLIC, MEMF_CHIP!MEMF_CLEAR, MEMF_CLEAR, and MEMF_PUBLIC!MEMF_CLEAR respectively. The following code fragment would do that: MemListDecl: DS.B LN_SIZE * reserve space for list node DC.W 5 * number of entries DC.L MEMF_CLEAR * entry #0 DC.L 2 DC.L MEMF_PUBLIC * entry #1 DC.L 4 DC.L MEMF_CHIP!MEMF_CLEAR * entry #2 DC.L 8 DC.L MEMF_CLEAR * entry #3 DC.L 16 DC.L MEMF_PUBLIC!MEMF_CLEAR * entry #4 DC.L 32 start: LEA.L MemListDecl(PC),A0 JSR _LVOAllocEntry(a6) BCLR.L #31,D0 BEQ.S success ------- Type of memory that we failed on is in D0 BUGS If any one of the allocations fails, this function fails to back out fully. This is fixed by the "SetPatch" program on V1.3 Workbench disks. SEE ALSO exec/memory.h exec.library/AllocMem exec.library/AllocMem NAME AllocMem -- allocate memory given certain requirements SYNOPSIS memoryBlock = AllocMem(byteSize, attributes) D0 D0 D1 void *AllocMem(ULONG, ULONG); FUNCTION This is the memory allocator to be used by system code and applications. It provides a means of specifying that the allocation should be made in a memory area accessible to the chips, or accessible to shared system code. Memory is allocated based on requirements and options. Any "requirement" must be met by a memory allocation, any "option" will be applied to the block regardless. AllocMem will try all memory spaces until one is found with the proper requirements and room for the memory request. INPUTS byteSize - the size of the desired block in bytes. (The operating system will automatically round this number to a multiple of the system memory chunk size) attributes - requirements If no flags are set, the system will return the best available memory block. For expanded systems, the fast memory pool is searched first. MEMF_CHIP: If the requested memory will be used by the Amiga custom chips, this flag *must* be set. Only certain parts of memory are reachable by the special chip sets' DMA circuitry. Chip DMA includes screen memory, images that are blitted, audio data, copper lists, sprites and Pre-V36 trackdisk.device buffers. MEMF_FAST: This is non-chip memory. If no flag is set MEMF_FAST is taken as the default. DO NOT SPECIFY MEMF_FAST unless you know exactly what you are doing! If MEMF_FAST is set, AllocMem() will fail on machines that only have chip memory! This flag may not be set when MEMF_CHIP is set. MEMF_PUBLIC: Memory that must not be mapped, swapped, or otherwise made non-addressable. ALL MEMORY THAT IS REFERENCED VIA INTERRUPTS AND/OR BY OTHER TASKS MUST BE EITHER PUBLIC OR LOCKED INTO MEMORY! This includes both code and data. MEMF_LOCAL: This is memory that will not go away after the CPU RESET instruction. Normally, autoconfig memory boards become unavailable after RESET while motherboard memory may still be available. This memory type is now automatically set in V36. Pre-V36 systems may not have this memory type and AllocMem() will then fail. MEMF_24BITDMA: This is memory that is within the address range of 24-bit DMA devices. (Zorro-II) This is required if you run a Zorro-II DMA device on a machine that has memory beyond the 24-bit addressing limit of Zorro-II. This memory type is now automatically set in V36. Pre-V36 systems may not have this memory type and AllocMem() will then fail. MEMF_KICK: This memory is memory that EXEC was able to access during/before the KickMem and KickTags are processed. This means that if you wish to use these, you should allocate memory with this flag. This flag is automaticly set by EXEC in V39. Pre-V39 systems may not have this memory type and AllocMem() will then fail. Also, *DO NOT* ever add memory the system with this flag set. EXEC will set the flag as needed if the memory matches the needs of EXEC. options MEMF_CLEAR: The memory will be initialized to all zeros. MEMF_REVERSE: This allocates memory from the top of the memory pool. It searches the pools in the same order, such that FAST memory will be found first. However, the memory will be allocated from the highest address available in the pool. This option is new as of V36. Note that this option has a bug in pre-V39 systems. MEMF_NO_EXPUNGE This will prevent an expunge to happen on a failed memory allocation. This option is new to V39 and will be ignored in V37. If a memory allocation with this flag set fails, the allocator will not cause any expunge operations. (See AddMemHandler()) RESULT memoryBlock - a pointer to the newly allocated memory block. If there are no free memory regions large enough to satisfy the request, zero will be returned. The pointer must be checked for zero before the memory block may be used! The memory block returned is long word aligned. WARNING The result of any memory allocation MUST be checked, and a viable error handling path taken. ANY allocation may fail if memory has been filled. EXAMPLES AllocMem(64,0L) - Allocate the best available memory AllocMem(25,MEMF_CLEAR) - Allocate the best available memory, and clear it before returning. AllocMem(128,MEMF_CHIP) - Allocate chip memory AllocMem(128,MEMF_CHIP|MEMF_CLEAR) - Allocate cleared chip memory AllocMem(821,MEMF_CHIP|MEMF_PUBLIC|MEMF_CLEAR) - Allocate cleared, public, chip memory. NOTE If the free list is corrupt, the system will panic with alert AN_MemCorrupt, $01000005. This function may not be called from interrupts. A DOS process will have its pr_Result2 field set to ERROR_NO_FREE_STORE if the memory allocation fails. SEE ALSO FreeMem exec.library/AllocPooled exec.library/AllocPooled NAME AllocPooled -- Allocate memory with the pool manager (V39) SYNOPSIS memory=AllocPooled(poolHeader,memSize) d0 a0 d0 void *AllocPooled(void *,ULONG); FUNCTION Allocate memSize bytes of memory, and return a pointer. NULL is returned if the allocation fails. Doing a DeletePool() on the pool will free all of the puddles and thus all of the allocations done with AllocPooled() in that pool. (No need to FreePooled() each allocation) INPUTS memSize - the number of bytes to allocate poolHeader - a specific private pool header. RESULT A pointer to the memory, or NULL. The memory block returned is long word aligned. NOTES The pool function do not protect an individual pool from multiple accesses. The reason is that in most cases the pools will be used by a single task. If your pool is going to be used by more than one task you must Semaphore protect the pool from having more than one task trying to allocate within the same pool at the same time. Warning: Forbid() protection *will not work* in the future. *Do NOT* assume that we will be able to make it work in the future. AllocPooled() may well break a Forbid() and as such can only be protected by a semaphore. To track sizes yourself, the following code can be used: Assumes a6=ExecBase ; ; Function to do AllocVecPooled(Pool,memSize) ; AllocVecPooled: addq.l #4,d0 ; Get space for tracking move.l d0,-(sp) ; Save the size jsr _LVOAllocPooled(a6) ; Call pool... move.l (sp)+,d1 ; Get size back... tst.l d0 ; Check for error beq.s avp_fail ; If NULL, failed! move.l d0,a0 ; Get pointer... move.l d1,(a0)+ ; Store size move.l a0,d0 ; Get result avp_fail: rts ; return ; ; Function to do FreeVecPooled(pool,memory) ; FreeVecPooled: move.l -(a1),d0 ; Get size / ajust pointer jmp _LVOFreePooled(a6) SEE ALSO FreePooled(), CreatePool(), DeletePool() exec.library/AllocSignal exec.library/AllocSignal NAME AllocSignal -- allocate a signal bit SYNOPSIS signalNum = AllocSignal(signalNum) D0 D0 BYTE AllocSignal(BYTE); FUNCTION Allocate a signal bit from the current tasks' pool. Either a particular bit, or the next free bit may be allocated. The signal associated with the bit will be properly initialized (cleared). At least 16 user signals are available per task. Signals should be deallocated before the task exits. If the signal is already in use (or no free signals are available) a -1 is returned. Allocated signals are only valid for use with the task that allocated them. WARNING Signals may not be allocated or freed from exception handling code. INPUTS signalNum - the desired signal number {of 0..31} or -1 for no preference. RESULTS signalNum - the signal bit number allocated {0..31}. If no signals are available, this function returns -1. SEE ALSO FreeSignal exec.library/AllocTrap exec.library/AllocTrap NAME AllocTrap -- allocate a processor trap vector SYNOPSIS trapNum = AllocTrap(trapNum) D0 D0 LONG AllocTrap(LONG); FUNCTION Allocate a trap number from the current task's pool. These trap numbers are those associated with the 68000 TRAP type instructions. Either a particular number, or the next free number may be allocated. If the trap is already in use (or no free traps are available) a -1 is returned. This function only affects the currently running task. Traps are sent to the trap handler pointed at by tc_TrapCode. Unless changed by user code, this points to a standard trap handler. The stack frame of the exception handler will be: 0(SP) = Exception vector number. This will be in the range of 32 to 47 (corresponding to the Trap #1...Trap #15 instructions). 4(SP) = 68000/68010/68020/68030, etc. exception frame tc_TrapData is not used. WARNING Traps may not be allocated or freed from exception handling code. You are not allowed to write to the exception table yourself. In fact, on some machines you will have trouble finding it - the VBR register may be used to remap its location. INPUTS trapNum - the desired trap number {of 0..15} or -1 for no preference. RESULTS trapNum - the trap number allocated {of 0..15}. If no traps are available, this function returns -1. Instructions of the form "Trap #trapNum" will be sent to the task's trap handler. SEE ALSO FreeTrap exec.library/AllocVec exec.library/AllocVec NAME AllocVec -- allocate memory and keep track of the size (V36) SYNOPSIS memoryBlock = AllocVec(byteSize, attributes) D0 D0 D1 void *AllocVec(ULONG, ULONG); FUNCTION This function works identically to AllocMem(), but tracks the size of the allocation. See the AllocMem() documentation for details. WARNING The result of any memory allocation MUST be checked, and a viable error handling path taken. ANY allocation may fail if memory has been filled. SEE ALSO FreeVec, AllocMem exec.library/AttemptSemaphore exec.library/AttemptSemaphore NAME AttemptSemaphore -- try to obtain without blocking SYNOPSIS success = AttemptSemaphore(signalSemaphore) D0 A0 LONG AttemptSemaphore(struct SignalSemaphore *); FUNCTION This call is similar to ObtainSemaphore(), except that it will not block if the semaphore could not be locked. INPUT signalSemaphore -- an initialized signal semaphore structure RESULT success -- TRUE if the semaphore was locked, false if some other task already possessed the semaphore. NOTE This call does NOT preserve registers. SEE ALSO ObtainSemaphore() ObtainSemaphoreShared(), ReleaseSemaphore(), exec/semaphores.h exec.library/AttemptSemaphoreShared exec.library/AttemptSemaphoreShared NAME AttemptSemaphoreShared -- try to obtain without blocking (V37) SYNOPSIS success = AttemptSemaphoreShared(signalSemaphore) D0 A0 LONG AttemptSemaphoreShared(struct SignalSemaphore *); FUNCTION This call is similar to ObtainSemaphoreShared(), except that it will not block if the semaphore could not be locked. INPUT signalSemaphore -- an initialized signal semaphore structure RESULT success -- TRUE if the semaphore was granted, false if some other task already possessed the semaphore in exclusive mode. NOTE This call does NOT preserve registers. Starting in V39 this call will grant the semaphore if the caller is already the owner of an exclusive lock on the semaphore. In pre-V39 systems this would not be the case. If you need this feature you can do the following workaround: LONG myAttemptSempahoreShared(struct SignalSemaphore *ss) { LONG result; /* Try for a shared semaphore */ if (!(result=AttemptSemaphoreShared(ss))) { /* Now try for the exclusive one... */ result=AttempSemaphore(ss); } return(result); } SEE ALSO ObtainSemaphore() ObtainSemaphoreShared(), ReleaseSemaphore(), exec/semaphores.h exec.library/AvailMem exec.library/AvailMem NAME AvailMem -- memory available given certain requirements SYNOPSIS size = AvailMem(attributes) D0 D1 ULONG AvailMem(ULONG); FUNCTION This function returns the amount of free memory given certain attributes. To find out what the largest block of a particular type is, add MEMF_LARGEST into the requirements argument. Returning the largest block is a slow operation. WARNING Due to the effect of multitasking, the value returned may not actually be the amount of free memory available at that instant. INPUTS requirements - a requirements mask as specified in AllocMem. Any of the AllocMem bits are valid, as is MEMF_LARGEST which returns the size of the largest block matching the requirements. RESULT size - total free space remaining (or the largest free block). NOTE For V36 Exec, AvailMem(MEMF_LARGEST) does a consistency check on the memory list. Alert AN_MemoryInsane will be pulled if any mismatch is noted. EXAMPLE AvailMem(MEMF_CHIP|MEMF_LARGEST); /* return size of largest available chip memory chunk */ SEE ALSO exec/memory.h exec.library/CacheClearE exec.library/CacheClearE NAME CacheClearE - Cache clearing with extended control (V37) SYNOPSIS CacheClearE(address,length,caches) a0 d0 d1 void CacheClearE(APTR,ULONG,ULONG); FUNCTION Flush out the contents of the CPU instruction and/or data caches. If dirty data cache lines are present, push them to memory first. Motorola CPUs have separate instruction and data caches. A data write does not update the instruction cache. If an instruction is written to memory or modified, the old instruction may still exist in the cache. Before attempting to execute the code, a flush of the instruction cache is required. For most systems, the data cache is not updated by Direct Memory Access (DMA), or if some external factor changes shared memory. Caches must be cleared after *any* operation that could cause invalid or stale data. The most common cases are DMA and modifying instructions using the processor. Some examples: Self modifying code Building Jump tables Run-time code patches Relocating code for use at different addresses. Loading code from disk INPUTS address - Address to start the operation. This may be rounded due to hardware granularity. length - Length of area to be cleared, or $FFFFFFFF to indicate all addresses should be cleared. caches - Bit flags to indicate what caches to affect. The current supported flags are: CACRF_ClearI ;Clear instruction cache CACRF_ClearD ;Clear data cache All other bits are reserved for future definition. NOTES On systems with a copyback mode cache, any dirty data is pushed to memory as a part of this operation. Regardless of the length given, the function will determine the most efficient way to implement the operation. For some cache systems, including the 68030, the overhead partially clearing a cache is often too great. The entire cache may be cleared. For all current Amiga models, Chip memory is set with Instruction caching enabled, data caching disabled. This prevents coherency conflicts with the blitter or other custom chip DMA. Custom chip registers are marked as non-cacheable by the hardware. The system takes care of appropriately flushing the caches for normal operations. The instruction cache is cleared by all calls that modify instructions, including LoadSeg(), MakeLibrary() and SetFunction(). SEE ALSO exec/execbase.i, CacheControl, CacheClearU exec.library/CacheClearU exec.library/CacheClearU NAME CacheClearU - User callable simple cache clearing (V37) SYNOPSIS CacheClearU() void CacheClearU(void); FUNCTION Flush out the contents of any CPU instruction and data caches. If dirty data cache lines are present, push them to memory first. Caches must be cleared after *any* operation that could cause invalid or stale data. The most common cases are DMA and modifying instructions using the processor. See the CacheClearE() autodoc for a more complete description. Some examples of when the cache needs clearing: Self modifying code Building Jump tables Run-time code patches Relocating code for use at different addresses. Loading code from disk SEE ALSO exec/execbase.i, CacheControl, CacheClearE exec.library/CacheControl exec.library/CacheControl NAME CacheControl - Instruction & data cache control SYNOPSIS oldBits = CacheControl(cacheBits,cacheMask) D0 D0 D1 ULONG CacheControl(ULONG,ULONG); FUNCTION This function provides global control of any instruction or data caches that may be connected to the system. All settings are global -- per task control is not provided. The action taken by this function will depend on the type of CPU installed. This function may be patched to support external caches, or different cache architectures. In all cases the function will attempt to best emulate the provided settings. Use of this function may save state specific to the caches involved. The list of supported settings is provided in the exec/execbase.i include file. The bits currently defined map directly to the Motorola 68030 CPU CACR register. Alternate cache solutions may patch into the Exec cache functions. Where possible, bits will be interpreted to have the same meaning on the installed cache. INPUTS cacheBits - new values for the bits specified in cacheMask. cacheMask - a mask with ones for all bits to be changed. RESULT oldBits - the complete prior values for all settings. NOTE As a side effect, this function clears all caches. SEE ALSO exec/execbase.i, CacheClearU, CacheClearE exec.library/CachePostDMA exec.library/CachePostDMA NAME CachePostDMA - Take actions after to hardware DMA (V37) SYNOPSIS CachePostDMA(vaddress,&length,flags) a0 a1 d0 CachePostDMA(APTR,LONG *,ULONG); FUNCTION Take all appropriate steps after Direct Memory Access (DMA). This function is primarily intended for writers of DMA device drivers. The action will depend on the CPU type installed, caching modes, and the state of any Memory Management Unit (MMU) activity. As implemented 68000 - Do nothing 68010 - Do nothing 68020 - Do nothing 68030 - Flush the data cache 68040 - Flush matching areas of the data cache ????? - External cache boards, Virtual Memory Systems, or future hardware may patch this vector to best emulate the intended behavior. With a Bus-Snooping CPU, this function my end up doing nothing. INPUTS address - Same as initially passed to CachePreDMA length - Same as initially passed to CachePreDMA flags - Values: DMA_NoModify - If the area was not modified (and thus there is no reason to flush the cache) set this bit. DMA_ReadFromRAM - Indicates that this DMA is a read from RAM to the DMA device (ie - a write to the hard drive) This flag is not required but if used must match in both the PreDMA and PostDMA calls. This flag *should* be used to help the system provide the best performance. This flag is safe in all versions of CachePostDMA() SEE ALSO exec/execbase.i, CachePreDMA, CacheClearU, CacheClearE exec.library/CachePreDMA exec.library/CachePreDMA NAME CachePreDMA - Take actions prior to hardware DMA (V37) SYNOPSIS paddress = CachePreDMA(vaddress,&length,flags) d0 a0 a1 d0 APTR CachePreDMA(APTR,LONG *,ULONG); FUNCTION Take all appropriate steps before Direct Memory Access (DMA). This function is primarily intended for writers of DMA device drivers. The action will depend on the CPU type installed, caching modes, and the state of any Memory Management Unit (MMU) activity. This function supports advanced cache architectures that have "copyback" modes. With copyback, write data may be cached, but not actually flushed out to memory. If the CPU has unflushed data at the time of DMA, data may be lost. As implemented 68000 - Do nothing 68010 - Do nothing 68020 - Do nothing 68030 - Do nothing 68040 - Write any matching dirty cache lines back to memory. As a side effect of the 68040's design, matching data cache lines are also invalidated -- future CPUs may be different. ????? - External cache boards, Virtual Memory Systems, or future hardware may patch this vector to best emulate the intended behavior. With a Bus-Snooping CPU, this function my end up doing nothing. INPUTS address - Base address to start the action. length - Pointer to a longword with a length. flags - Values: DMA_Continue - Indicates this call is to complete a prior request that was broken up. DMA_ReadFromRAM - Indicates that this DMA is a read from RAM to the DMA device (ie - a write to the hard drive) This flag is not required but if used must match in both the PreDMA and PostDMA calls. This flag *should* be used to help the system provide the best performance. This flag is safe in all versions of CachePreDMA() RESULTS paddress- Physical address that corresponds to the input virtual address. &length - This length value will be updated to reflect the contiguous length of physical memory present at paddress. This may be smaller than the requested length. To get the mapping for the next chunk of memory, call the function again with a new address, length, and the DMA_Continue flag. NOTE Due to processor granularity, areas outside of the address range may be affected by the cache flushing actions. Care has been taken to ensure that no harm is done outside the range, and that activities on overlapping cache lines won't harm data. SEE ALSO exec/execbase.i, CachePostDMA, CacheClearU, CacheClearE exec.library/Cause exec.library/Cause NAME Cause -- cause a software interrupt SYNOPSIS Cause(interrupt) A1 void Cause(struct Interrupt *); FUNCTION This function causes a software interrupt to occur. If it is called from user mode (and processor level 0), the software interrupt will preempt the current task. This call is often used by high-level hardware interrupts to defer medium-length processing down to a lower interrupt level. Note that a software interrupt is still a real interrupt, and must obey the same restrictions on what system function it may call. Currently only 5 software interrupt priorities are implemented: -32, -16, 0, +16, and +32. Priorities in between are truncated, values outside the -32/+32 range are not allowed. NOTE When setting up the Interrupt structure, set the node type to NT_INTERRUPT, or NT_UNKOWN. IMPLEMENTATION 1> Checks if the node type is NT_SOFTINT. If so does nothing since the softint is already pending. No nest count is maintained. 2> Sets the node type to NT_SOFTINT. 3> Links into one of the 5 priority queues. 4> Pokes the hardware interrupt bit used for softints. The node type returns to NT_INTERRUPT after removal from the list. INPUTS interrupt - pointer to a properly initialized interrupt node BUGS Unlike other Interrupts, SoftInts must preserve the value of A6. exec.library/CheckIO exec.library/CheckIO NAME CheckIO -- get the status of an IORequest SYNOPSIS result = CheckIO(iORequest) D0 A1 struct IORequest *CheckIO(struct IORequest *); FUNCTION This function determines the current state of an I/O request and returns FALSE if the I/O has not yet completed. This function effectively hides the internals of the I/O completion mechanism. CheckIO() will NOT remove the returned IORequest from the reply port. This is best performed with WaitIO(). If the request has already completed, WaitIO() will return quickly. Use of the Remove() function is dangerous, since other tasks may still be adding things to your message port; a Disable() would be required. This function should NOT be used to busy loop (looping until IO is complete). WaitIO() is provided for that purpose. INPUTS iORequest - pointer to an I/O request block RESULTS result - NULL if I/O is still in progress. Otherwise D0 points to the IORequest block. NOTE CheckIO can hang if called on an IORequest that has never been used. This occurs if LN_TYPE of the IORequest is set to "NT_MESSAGE". Instead simply set LN_TYPE to 0. SEE ALSO DoIO, SendIO, WaitIO, AbortIO exec.library/CloseDevice exec.library/CloseDevice NAME CloseDevice -- conclude access to a device SYNOPSIS CloseDevice(iORequest) A1 void CloseDevice(struct IORequest *); FUNCTION This function informs the device that access to a device/unit previously opened has been concluded. The device may perform certain house-cleaning operations. The user must ensure that all outstanding IORequests have been returned before closing the device. The AbortIO function can kill any stragglers. After a close, the I/O request structure is free to be reused. Starting with V36 exec it is safe to CloseDevice() with an IORequest that is either cleared to zeros, or failed to open. INPUTS iORequest - pointer to an I/O request structure SEE ALSO OpenDevice exec.library/CloseLibrary exec.library/CloseLibrary NAME CloseLibrary -- conclude access to a library SYNOPSIS CloseLibrary(library) A1 void CloseLibrary(struct Library *); FUNCTION This function informs the system that access to the given library has been concluded. The user must not reference the library or any function in the library after this close. Starting with V36, it is safe to pass a NULL instead of a library pointer. INPUTS library - pointer to a library node NOTE Library writers must pass a SegList pointer or NULL back from their open point. This value is used by the system, and not visible as a return code from CloseLibrary. SEE ALSO OpenLibrary exec.library/ColdReboot exec.library/ColdReboot NAME ColdReboot - reboot the Amiga (V36) SYNOPSIS ColdReboot() void ColdReboot(void); FUNCTION Reboot the machine. All external memory and periperals will be RESET, and the machine will start its power up diagnostics. This function never returns. INPUT A chaotic pile of disoriented bits. RESULTS An altogether totally integrated living system. exec.library/CopyMem exec.library/CopyMem NAME CopyMem - general purpose memory copy function SYNOPSIS CopyMem( source, dest, size ) A0 A1 D0 void CopyMem(APTR,APTR,ULONG); FUNCTION CopyMem is a general purpose, fast memory copy function. It can deal with arbitrary lengths, with its pointers on arbitrary alignments. It attempts to optimize larger copies with more efficient copies, it uses byte copies for small moves, parts of larger copies, or the entire copy if the source and destination are misaligned with respect to each other. Arbitrary overlapping copies are not supported. The internal implementation of this function will change from system to system, and may be implemented via hardware DMA. INPUTS source - a pointer to the source data region dest - a pointer to the destination data region size - the size (in bytes) of the memory area. Zero copies zero bytes SEE ALSO CopyMemQuick exec.library/CopyMemQuick exec.library/CopyMemQuick NAME CopyMemQuick - optimized memory copy function SYNOPSIS CopyMemQuick( source, dest, size ) A0 A1 D0 void CopyMemQuick(ULONG *,ULONG *,ULONG); FUNCTION CopyMemQuick is a highly optimized memory copy function, with restrictions on the size and alignment of its arguments. Both the source and destination pointers must be longword aligned. In addition, the size must be an integral number of longwords (e.g. the size must be evenly divisible by four). Arbitrary overlapping copies are not supported. The internal implementation of this function will change from system to system, and may be implemented via hardware DMA. INPUTS source - a pointer to the source data region, long aligned dest - a pointer to the destination data region, long aligned size - the size (in bytes) of the memory area. Zero copies zero bytes. SEE ALSO CopyMem exec.library/CreateIORequest exec.library/CreateIORequest NAME CreateIORequest() -- create an IORequest structure (V36) SYNOPSIS ioReq = CreateIORequest( ioReplyPort, size ); A0 D0 struct IORequest *CreateIORequest(struct MsgPort *, ULONG); FUNCTION Allocates memory for and initializes a new IO request block of a user-specified number of bytes. The number of bytes must be at least as large as a "struct Message". INPUTS ioReplyPort - Pointer to a port for replies (an initialized message port, as created by CreateMsgPort() ). If NULL, this function fails. size - the size of the IO request to be created. RESULT ioReq - A pointer to the new IORequest block, or NULL. SEE ALSO DeleteIORequest, CreateMsgPort(), amiga.lib/CreateExtIO() exec.library/CreateMsgPort exec.library/CreateMsgPort NAME CreateMsgPort - Allocate and initialize a new message port (V36) SYNOPSIS CreateMsgPort() struct MsgPort * CreateMsgPort(void); FUNCTION Allocates and initializes a new message port. The message list of the new port will be prepared for use (via NewList). A signal bit will be allocated, and the port will be set to signal your task when a message arrives (PA_SIGNAL). You *must* use DeleteMsgPort() to delete ports created with CreateMsgPort()! RESULT MsgPort - A new MsgPort structure ready for use, or NULL if out of memory or signals. If you wish to add this port to the public port list, fill in the ln_Name and ln_Pri fields, then call AddPort(). Don't forget RemPort()! SEE ALSO DeleteMsgPort(), exec/AddPort(), exec/ports.h, amiga.lib/CreatePort() exec.library/CreatePool exec.library/CreatePool NAME CreatePool -- Generate a private memory pool header (V39) SYNOPSIS newPool=CreatePool(memFlags,puddleSize,threshSize) a0 d0 d1 d2 void *CreatePool(ULONG,ULONG,ULONG); FUNCTION Allocate and prepare a new memory pool header. Each pool is a separate tracking system for memory of a specific type. Any number of pools may exist in the system. Pools automatically expand and shrink based on demand. Fixed sized "puddles" are allocated by the pool manager when more total memory is needed. Many small allocations can fit in a single puddle. Allocations larger than the threshSize are allocation in their own puddles. At any time individual allocations may be freed. Or, the entire pool may be removed in a single step. INPUTS memFlags - a memory flags specifier, as taken by AllocMem. puddleSize - the size of Puddles... threshSize - the largest allocation that goes into normal puddles This *MUST* be less than or equal to puddleSize (CreatePool() will fail if it is not) RESULT The address of a new pool header, or NULL for error. SEE ALSO DeletePool(), AllocPooled(), FreePooled(), exec/memory.i exec.library/Deallocate exec.library/Deallocate NAME Deallocate -- deallocate a block of memory SYNOPSIS Deallocate(memHeader, memoryBlock, byteSize) A0 A1 D0 void Deallocate(struct MemHeader *,APTR,ULONG); FUNCTION This function deallocates memory by returning it to the appropriate private free memory pool. This function can be used to free an entire block allocated with the above function, or it can be used to free a sub-block of a previously allocated block. Sub-blocks must be an even multiple of the memory chunk size (currently 8 bytes). This function can even be used to add a new free region to an existing MemHeader, however the extent pointers in the MemHeader will no longer be valid. If memoryBlock is not on a block boundary (MEM_BLOCKSIZE) then it will be rounded down in a manner compatible with Allocate(). Note that this will work correctly with all the memory allocation functions, but may cause surprises if one is freeing only part of a region. The size of the block will be rounded up, so the freed block will fill to an even memory block boundary. INPUTS memHeader - points to the memory header this block is part of. memoryBlock - address of memory block to free. byteSize - the size of the block in bytes. If NULL, nothing happens. SEE ALSO Allocate, exec/memory.h exec.library/Debug exec.library/Debug NAME Debug -- run the system debugger SYNOPSIS Debug(flags) D0 void Debug(ULONG); FUNCTION This function calls the system debugger. By default this debugger is "SAD" in >= V39 and "ROM-WACK" in < V39. Other debuggers are encouraged to take over this entry point (via SetFunction()) so that when an application calls Debug(), the alternative debugger will get control. Currently a zero is passed to allow future expansion. NOTE The Debug() call may be made when the system is in a questionable state; if you have a SetFunction() patch, make few assumptions, be prepared for Supervisor mode, and be aware of differences in the Motorola stack frames on the 68000,'10,'20,'30,'40 (etc.) BUGS In ROMWack, calling this function in SUPERVISOR state would have caused the a5 register to be trashed and the user stack pointer to be trashed. As of V39 (and the instroduction of SAD) this is no longer the case. However, calling this function in Supervisor state is a bit "tricky" at best... Note that due to a bug, pre-V40 SAD had the command codes wrong. See the SAD autodoc for more details. SEE ALSO SetFunction() your favorite debugger's manual... the SAD autodocs... the ROM-WACK chapter of the ROM Kernel Manual... (pre-V39) exec.library/DeleteIORequest exec.library/DeleteIORequest NAME DeleteIORequest() - Free a request made by CreateIORequest() (V36) SYNOPSIS DeleteIORequest( ioReq ); a0 void DeleteIORequest(struct IORequest *); FUNCTION Frees up an IO request as allocated by CreateIORequest(). INPUTS ioReq - A pointer to the IORequest block to be freed, or NULL. This function uses the mn_Length field to determine how much memory to free. SEE ALSO CreateIORequest(), amiga.lib/DeleteExtIO() exec.library/DeleteMsgPort exec.library/DeleteMsgPort NAME DeleteMsgPort - Free a message port created by CreateMsgPort (V36) SYNOPSIS DeleteMsgPort(msgPort) a0 void DeleteMsgPort(struct MsgPort *); FUNCTION Frees a message port created by CreateMsgPort(). All messages that may have been attached to this port must have already been replied to. INPUTS msgPort - A message port. NULL for no action. SEE ALSO CreateMsgPort(), amiga.lib/DeletePort() exec.library/DeletePool exec.library/DeletePool NAME DeletePool -- Drain an entire memory pool (V39) SYNOPSIS DeletePool(poolHeader) a0 void DeletePool(void *); FUNCTION Frees all memory in all pudles of the specified pool header, then deletes the pool header. Individual free calls are not needed. INPUTS poolHeader - as returned by CreatePool(). SEE ALSO CreatePool(), AllocPooled(), FreePooled() exec.library/Disable exec.library/Disable NAME Disable -- disable interrupt processing. SYNOPSIS Disable(); void Disable(void); FUNCTION Prevents interrupts from being handled by the system, until a matching Enable() is executed. Disable() implies Forbid(). DO NOT USE THIS CALL WITHOUT GOOD JUSTIFICATION. THIS CALL IS VERY DANGEROUS! RESULTS All interrupt processing is deferred until the task executing makes a call to Enable() or is placed in a wait state. Normal task rescheduling does not occur while interrupts are disabled. In order to restore normal interrupt processing, the programmer must execute exactly one call to Enable() for every call to Disable(). IMPORTANT REMINDER: It is important to remember that there is a danger in using disabled sections. Disabling interrupts for more than ~250 microseconds will prevent vital system functions (especially serial I/0) from operating in a normal fashion. Think twice before using Disable(), then think once more. After all that, think again. With enough thought, the need for a Disable() can often be eliminated. For the user of many device drivers, a write to disable *only* the particular interrupt of interest can replace a Disable(). For example: MOVE.W #INTF_PORTS,_intena Do not use a macro for Disable(), insist on the real thing. This call may be made from interrupts, it will have the effect of locking out all higher-level interrupts (lower-level interrupts are automatically disabled by the CPU). Note: In the event of a task entering a Wait() after disabling interrupts, the system "breaks" the disabled state and runs normally until the task which called Disable() is rescheduled. NOTE This call is guaranteed to preserve all registers. SEE ALSO Forbid, Permit, Enable exec.library/DoIO exec.library/DoIO NAME DoIO -- perform an I/O command and wait for completion SYNOPSIS error = DoIO(iORequest) D0 A1 BYTE DoIO(struct IORequest *); FUNCTION This function requests a device driver to perform the I/O command specified in the I/O request. This function will always wait until the I/O request is fully complete. DoIO() handles all the details, including Quick I/O, waiting for the request, and removing the reply message, etc.. IMPLEMENTATION This function first tries to complete the IO via the "Quick I/O" mechanism. The io_Flags field is always set to IOF_QUICK (0x01) before the internal device call. The LN_TYPE field is used internally to flag completion. Active requests have type NT_MESSAGE. Requests that have been replied have type NT_REPLYMSG. It is illegal to start IO using a still active IORequest, or a request with type NT_REPLYMSG. INPUTS iORequest - pointer to an IORequest initialized by OpenDevice() RESULTS error - a sign-extended copy of the io_Error field of the IORequest. Most device commands require that the error return be checked. SEE ALSO SendIO, CheckIO, WaitIO, AbortIO, amiga.lib/BeginIO exec.library/Enable exec.library/Enable NAME Enable -- permit system interrupts to resume. SYNOPSIS Enable(); void Enable(void); FUNCTION Allow system interrupts to again occur normally, after a matching Disable() has been executed. RESULTS Interrupt processing is restored to normal operation. The programmer must execute exactly one call to Enable() for every call to Disable(). NOTE This call is guaranteed to preserve all registers. SEE ALSO Forbid, Permit, Disable exec.library/Enqueue exec.library/Enqueue NAME Enqueue -- insert or append node to a system queue SYNOPSIS Enqueue(list, node) A0 A1 void Enqueue(struct List *, struct Node *); FUNCTION Insert or append a node into a system queue. The insert is performed based on the node priority -- it will keep the list properly sorted. New nodes will be inserted in front of the first node with a lower priority. Hence a FIFO queue for nodes of equal priority WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS list - a pointer to the system queue header node - the node to enqueue. This must be a full featured node with type, priority and name fields. SEE ALSO AddHead, AddTail, Insert, Remove, RemHead, RemTail exec.library/FindName exec.library/FindName NAME FindName -- find a system list node with a given name SYNOPSIS node = FindName(start, name) D0,Z A0 A1 struct Node *FindName(struct List *, STRPTR); FUNCTION Traverse a system list until a node with the given name is found. To find multiple occurrences of a string, this function may be called with a node starting point. No arbitration is done for access to the list! If multiple tasks access the same list, an arbitration mechanism such as SignalSemaphores must be used. INPUTS start - a list header or a list node to start the search (if node, this one is skipped) name - a pointer to a name string terminated with NULL RESULTS node - a pointer to the node with the same name else zero to indicate that the string was not found. exec.library/FindPort exec.library/FindPort NAME FindPort -- find a given system message port SYNOPSIS port = FindPort(name) D0 A1 struct MsgPort *FindPort(STRPTR); FUNCTION This function will search the system message port list for a port with the given name. The first port matching this name will be returned. No arbitration of the port list is done. This function MUST be protected with A Forbid()/Permit() pair! EXAMPLE #include <exec/types.h> struct MsgPort *FindPort(); ULONG SafePutToPort(message, portname) struct Message *message; STRPTR portname; { struct MsgPort *port; Forbid(); port = FindPort(portname); if (port) PutMsg(port,message); Permit(); return((ULONG)port); /* If zero, the port has gone away */ } INPUT name - name of the port to find RETURN port - a pointer to the message port, or zero if not found. exec.library/FindResident exec.library/FindResident NAME FindResident - find a resident module by name SYNOPSIS resident = FindResident(name) D0 A1 struct Resident *FindResident(STRPTR); FUNCTION Search the system resident tag list for a resident tag ("ROMTag") with the given name. If found return a pointer to the resident tag structure, else return zero. Resident modules are used by the system to pull all its parts together at startup. Resident tags are also found in disk based devices and libraries. INPUTS name - pointer to name string RESULT resident - pointer to the resident tag structure or zero if none found. SEE ALSO exec/resident.h, InitResident exec.library/FindSemaphore exec.library/FindSemaphore NAME FindSemaphore -- find a given system signal semaphore SYNOPSIS signalSemaphore = FindSemaphore(name) D0 A1 struct SignalSemaphore *FindSemaphore(STRPTR); FUNCTION This function will search the system signal semaphore list for a semaphore with the given name. The first semaphore matching this name will be returned. This function does not arbitrate for access to the semaphore list, surround the call with a Forbid()/Permit() pair. INPUT name - name of the semaphore to find RESULT semaphore - a pointer to the signal semaphore, or zero if not found. exec.library/FindTask exec.library/FindTask NAME FindTask -- find a task with the given name or find oneself SYNOPSIS task = FindTask(name) D0 A1 struct Task *FindTask(STRPTR); FUNCTION This function will check all task queues for a task with the given name, and return a pointer to its task control block. If a NULL name pointer is given a pointer to the current task will be returned. Finding oneself with a NULL for the name is very quick. Finding a task by name is very system expensive, and will disable interrupts for a long time. Since a task may remove itself at any time, a Forbid()/Permit() pair may be needed to ensure the pointer returned by FindTask() is still valid when used. INPUT name - pointer to a name string RESULT task - pointer to the task (or Process) exec.library/Forbid exec.library/Forbid NAME Forbid -- forbid task rescheduling. SYNOPSIS Forbid() void Forbid(void); FUNCTION Prevents other tasks from being scheduled to run by the dispatcher, until a matching Permit() is executed, or this task is scheduled to Wait(). Interrupts are NOT disabled. DO NOT USE THIS CALL WITHOUT GOOD JUSTIFICATION. THIS CALL IS DANGEROUS! RESULTS The current task will not be rescheduled as long as it is ready to run. In the event that the current task enters a wait state, other tasks may be scheduled. Upon return from the wait state, the original task will continue to run without disturbing the Forbid(). Calls to Forbid() nest. In order to restore normal task rescheduling, the programmer must execute exactly one call to Permit() for every call to Forbid(). WARNING In the event of a task entering a Wait() after a Forbid(), the system "breaks" the forbidden state and runs normally until the task which called Forbid() is rescheduled. If caution is not taken, this can cause subtle bugs, since any device or DOS call will (in effect) cause your task to wait. Forbid() is not useful or safe from within interrupt code (All interrupts are always higher priority than tasks, and interrupts are allowed to break a Forbid()). NOTE This call is guaranteed to preserve all registers. SEE ALSO Permit, Disable, ObtainSemaphore, ObtainSemaphoreShared exec.library/FreeEntry exec.library/FreeEntry NAME FreeEntry -- free many regions of memory SYNOPSIS FreeEntry(memList) A0 void FreeEntry(struct MemList *); FUNCTION This function takes a memList structure (as returned by AllocEntry) and frees all the entries. INPUTS memList -- pointer to structure filled in with MemEntry structures SEE ALSO AllocEntry exec.library/FreeMem exec.library/FreeMem NAME FreeMem -- deallocate with knowledge SYNOPSIS FreeMem(memoryBlock, byteSize) A1 D0 void FreeMem(void *,ULONG); FUNCTION Free a region of memory, returning it to the system pool from which it came. Freeing partial blocks back into the system pool is unwise. NOTE If a block of memory is freed twice, the system will Guru. The Alert is AN_FreeTwice ($01000009). If you pass the wrong pointer, you will probably see AN_MemCorrupt $01000005. Future versions may add more sanity checks to the memory lists. INPUTS memoryBlock - pointer to the memory block to free byteSize - the size of the desired block in bytes. (The operating system will automatically round this number to a multiple of the system memory chunk size) SEE ALSO AllocMem exec.library/FreePooled exec.library/FreePooled NAME FreePooled -- Free pooled memory (V39) SYNOPSIS FreePooled(poolHeader,memory,memSize) a0 a1 d0 void FreePooled(void *,void *,ULONG); FUNCTION Deallocates memory allocated by AllocPooled(). The size of the allocation *MUST* match the size given to AllocPooled(). The reason the pool functions do not track individual allocation sizes is because many of the uses of pools have small allocation sizes and the tracking of the size would be a large overhead. Only memory allocated by AllocPooled() may be freed with this function! Doing a DeletePool() on the pool will free all of the puddles and thus all of the allocations done with AllocPooled() in that pool. (No need to FreePooled() each allocation) INPUTS memory - pointer to memory allocated by AllocPooled. poolHeader - a specific private pool header. NOTES The pool function do not protect an individual pool from multiple accesses. The reason is that in most cases the pools will be used by a single task. If your pool is going to be used by more than one task you must Semaphore protect the pool from having more than one task trying to allocate within the same pool at the same time. Warning: Forbid() protection *will not work* in the future. *Do NOT* assume that we will be able to make it work in the future. FreePooled() may well break a Forbid() and as such can only be protected by a semaphore. To track sizes yourself, the following code can be used: Assumes a6=ExecBase ; ; Function to do AllocVecPooled(Pool,memSize) ; AllocVecPooled: addq.l #4,d0 ; Get space for tracking move.l d0,-(sp) ; Save the size jsr _LVOAllocPooled(a6) ; Call pool... move.l (sp)+,d1 ; Get size back... tst.l d0 ; Check for error beq.s avp_fail ; If NULL, failed! move.l d0,a0 ; Get pointer... move.l d1,(a0)+ ; Store size move.l a0,d0 ; Get result avp_fail: rts ; return ; ; Function to do FreeVecPooled(pool,memory) ; FreeVecPooled: move.l -(a1),d0 ; Get size / ajust pointer jmp _LVOFreePooled(a6) SEE ALSO AllocPooled(), CreatePool(), DeletePool() exec.library/FreeSignal exec.library/FreeSignal NAME FreeSignal -- free a signal bit SYNOPSIS FreeSignal(signalNum) D0 void FreeSignal(BYTE); FUNCTION This function frees a previously allocated signal bit for reuse. This call must be performed while running in the same task in which the signal was allocated. WARNING Signals may not be allocated or freed from exception handling code. NOTE Starting with V37, an attempt to free signal -1 is harmless. INPUTS signalNum - the signal number to free {0..31}. exec.library/FreeTrap exec.library/FreeTrap NAME FreeTrap -- free a processor trap SYNOPSIS FreeTrap(trapNum) D0 void FreeTrap(ULONG); FUNCTION This function frees a previously allocated trap number for reuse. This call must be performed while running in the same task in which the trap was allocated. WARNING Traps may not be allocated or freed from exception handling code. INPUTS trapNum - the trap number to free {of 0..15} exec.library/FreeVec exec.library/FreeVec NAME FreeVec -- return AllocVec() memory to the system (V36) SYNOPSIS FreeVec(memoryBlock) A1 void FreeVec(void *); FUNCTION Free an allocation made by the AllocVec() call. The memory will be returned to the system pool from which it came. NOTE If a block of memory is freed twice, the system will Guru. The Alert is AN_FreeTwice ($01000009). If you pass the wrong pointer, you will probably see AN_MemCorrupt $01000005. Future versions may add more sanity checks to the memory lists. INPUTS memoryBlock - pointer to the memory block to free, or NULL. SEE ALSO AllocVec exec.library/GetCC exec.library/GetCC NAME GetCC -- get condition codes in a 68010 compatible way. SYNOPSIS conditions = GetCC() D0 UWORD GetCC(void); FUNCTION The 68000 processor has a "MOVE SR,<ea>" instruction which gets a copy of the processor condition codes. On the 68010,20 and 30 CPUs, "MOVE SR,<ea>" is privileged. User code will trap if it is attempted. These processors need to use the "MOVE CCR,<ea>" instruction instead. This function provides a means of obtaining the CPU condition codes in a manner that will make upgrades transparent. This function is VERY short and quick. RESULTS conditions - the 680XX condition codes NOTE This call is guaranteed to preserve all registers. This function may be implemented as code right in the jump table. exec.library/GetMsg exec.library/GetMsg NAME GetMsg -- get next message from a message port SYNOPSIS message = GetMsg(port) D0 A0 struct Message *GetMsg(struct MsgPort *); FUNCTION This function receives a message from a given message port. It provides a fast, non-copying message receiving mechanism. The received message is removed from the message port. This function will not wait. If a message is not present this function will return zero. If a program must wait for a message, it can Wait() on the signal specified for the port or use the WaitPort() function. There can only be one task waiting for any given port. Getting a message does not imply to the sender that the message is free to be reused by the sender. When the receiver is finished with the message, it may ReplyMsg() it back to the sender. Getting a signal does NOT always imply a message is ready. More than one message may arrive per signal, and signals may show up without messages. Typically you must loop to GetMsg() until it returns zero, then Wait() or WaitPort(). INPUT port - a pointer to the receiver message port RESULT message - a pointer to the first message available. If there are no messages, return zero. Callers must be prepared for zero at any time. SEE ALSO PutMsg, ReplyMsg, WaitPort, Wait, exec/ports.h exec.library/InitCode exec.library/InitCode NAME InitCode - initialize resident code modules (internal function) SYNOPSIS InitCode(startClass, version) D0 D1 void InitCode(ULONG,ULONG); FUNCTION (This function may be ignored by application programmers) Call InitResident() for all resident modules in the ResModules array with the given startClass and with versions equal or greater than that specified. The segList parameter is passed as zero. Resident modules are used by the system to pull all its parts together at startup. Modules are initialized in a prioritized order. Modules that do not have a startclass should be of priority -120. RTF_AFTERDOS modules should start at -100 (working down). INPUTS startClass - the class of code to be initialized: BITDEF RT,COLDSTART,0 BITDEF RT,SINGLETASK,1 ;ExecBase->ThisTask==0 (V36 only) BITDEF RT,AFTERDOS,2 ;(V36 only) version - a major version number SEE ALSO ResidentTag (RT) structure definition (resident.h) exec.library/InitResident exec.library/InitResident NAME InitResident - initialize resident module SYNOPSIS object = InitResident(resident, segList) D0 A1 D1 APTR InitResident(struct Resident *,ULONG); FUNCTION Initialize a ROMTag. ROMTags are used to link system modules together. Each disk based device or library must contain a ROMTag structure in the first code hunk. Once the validity of the ROMTag is verified, the RT_INIT pointer is jumped to with the following registers: D0 = 0 A0 = segList A6 = ExecBase INPUTS resident - Pointer to a ROMTag segList - SegList of the loaded object, if loaded from disk. Libraries & Devices will cache this value for later return at close or expunge time. Pass NULL for ROM modules. RESULTS object - Return value from the init code, usually the library or device base. NULL for failure. AUTOINIT FEATURE An automatic method of library/device base and vector table initialization is also provided by InitResident(). The initial code hunk of the library or device should contain "MOVEQ #-1,d0; RTS;". Following that must be an initialized Resident structure with RTF_AUTOINIT set in rt_Flags, and an rt_Init pointer which points to four longwords. These four longwords will be used in a call to MakeLibrary(); - The size of your library/device base structure including initial Library or Device structure. - A pointer to a longword table of standard, then library specific function offsets, terminated with -1L. (short format offsets are also acceptable) - Pointer to data table in exec/InitStruct format for initialization of Library or Device structure. - Pointer to library initialization function, or NULL. Calling sequence: D0 = library base A0 = segList A6 = ExecBase This function must return in D0 the library/device base to be linked into the library/device list. If the initialization function fails, the device memory must be manually deallocated, then NULL returned in D0. SEE ALSO exec/resident.i, FindResident exec.library/InitSemaphore exec.library/InitSemaphore NAME InitSemaphore -- initialize a signal semaphore SYNOPSIS InitSemaphore(signalSemaphore) A0 void InitSemaphore(struct SignalSemaphore *); FUNCTION This function initializes a signal semaphore and prepares it for use. It does not allocate anything, but does initialize list pointers and the semaphore counters. Semaphores are often used to protect critical data structures or hardware that can only be accessed by one task at a time. After initialization, the address of the SignalSemaphore may be made available to any number of tasks. Typically a task will try to ObtainSemaphore(), passing this address in. If no other task owns the semaphore, then the call will lock and return quickly. If more tasks try to ObtainSemaphore(), they will be put to sleep. When the owner of the semaphore releases it, the next waiter in turn will be woken up. Semaphores are often preferable to the old-style Forbid()/Permit() type arbitration. With Forbid()/Permit() *all* other tasks are prevented from running. With semaphores, only those tasks that need access to whatever the semaphore protects are subject to waiting. INPUT signalSemaphore -- a signal semaphore structure (with all fields set to zero before the call) SEE ALSO ObtainSemaphore, ObtainSemaphoreShared, AttemptSemaphore, ReleaseSemaphore, Procure, Vacate, exec/semaphores.h exec.library/InitStruct exec.library/InitStruct NAME InitStruct - initialize memory from a table SYNOPSIS InitStruct(initTable, memory, size); A1 A2 D0 void InitStruct(struct InitStruct *, APTR, ULONG); FUNCTION Clear a memory area, then set up default values according to the data and offset values in the initTable. Typically only assembly programs take advantage of this function, and only with the macros defined in "exec/initializers.i". The initialization table has byte commands to |a ||byte| |given||byte| |once | load |count||word| into |next ||rptr| offset, |repetitively | |long| Not all combinations are supported. The offset, when specified, is relative to the memory pointer provided (Memory), and is initially zero. The initialization data (InitTable) contains byte commands whose 8 bits are interpreted as follows: ddssnnnn dd the destination type (and size): 00 no offset, use next destination, nnnn is count 01 no offset, use next destination, nnnn is repeat 10 destination offset is in the next byte, nnnn is count 11 destination offset is in the next 24-bits, nnnn is count ss the size and location of the source: 00 long, from the next two aligned words 01 word, from the next aligned word 10 byte, from the next byte 11 ERROR - will cause an ALERT (see below) nnnn the count or repeat: count the (number+1) of source items to copy repeat the source is copied (number+1) times. initTable commands are always read from the next even byte. Given destination offsets are always relative to the memory pointer (A2). The command %00000000 ends the InitTable stream: use %00010001 if you really want to copy one longword without a new offset. 24 bit APTR not supported for 68020 compatibility -- use long. INPUTS initTable - the beginning of the commands and data to init Memory with. Must be on an even boundary unless only byte initialization is done. End table with "dc.b 0" or "dc.w 0". memory - the beginning of the memory to initialize. Must be on an even boundary if size is specified. size - the size of memory, which is used to clear it before initializing it via the initTable. If Size is zero, memory is not cleared before initializing. size must be an even number. SEE ALSO exec/initializers.i exec.library/Insert exec.library/Insert NAME Insert -- insert a node into a list SYNOPSIS Insert(list, node, listNode) A0 A1 A2 void Insert(struct List *, struct Node *, struct Node *); FUNCTION Insert a node into a doubly linked list AFTER a given node position. Insertion at the head of a list is possible by passing a zero value for listNode, though the AddHead function is slightly faster for that special case. WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS list - a pointer to the target list header node - the node to insert listNode - the node after which to insert SEE ALSO AddHead, AddTail, Enqueue, RemHead, Remove, RemTail exec.library/MakeFunctions exec.library/MakeFunctions NAME MakeFunctions -- construct a function jump table SYNOPSIS tableSize = MakeFunctions(target, functionArray, funcDispBase) D0 A0 A1 A2 ULONG MakeFunctions(APTR,APTR,APTR); FUNCTION A low level function used by MakeLibrary to build jump tables of the type used by libraries, devices and resources. It allows the table to be built anywhere in memory, and can be used both for initialization and replacement. This function also supports function pointer compression by expanding relative displacements into absolute pointers. The processor instruction cache is cleared after the table building. INPUT destination - the target address for the high memory end of the function jump table. Typically this will be the library base pointer. functionArray - pointer to an array of function pointers or function displacements. If funcDispBase is zero, the array is assumed to contain absolute pointers to functions. If funcDispBase is not zero, then the array is assumed to contain word displacements to functions. In both cases, the array is terminated by a -1 (of the same size as the actual entry. funcDispBase - pointer to the base about which all function displacements are relative. If zero, then the function array contains absolute pointers. RESULT tableSize - size of the new table in bytes (for LIB_NEGSIZE). SEE ALSO exec/MakeLibrary exec.library/MakeLibrary exec.library/MakeLibrary NAME MakeLibrary -- construct a library SYNOPSIS library = MakeLibrary(vectors, structure, init, dSize, segList) D0 A0 A1 A2 D0 D1 struct Library *MakeLibrary (APTR,struct InitStruct *,APTR,ULONG,BPTR); FUNCTION This function is used for constructing a library vector and data area. The same call is used to make devices. Space for the library is allocated from the system's free memory pool. The data portion of the library is initialized. init may point to a library specific entry point. NOTE Starting with V36, the library base is longword adjusted. The lib_PosSize and lib_NegSize fields of the library structure are adjusted to match. INPUTS vectors - pointer to an array of function pointers or function displacements. If the first word of the array is -1, then the array contains relative word displacements (based off of vectors); otherwise, the array contains absolute function pointers. The vector list is terminated by a -1 (of the same size as the pointers). structure - points to an "InitStruct" data region. If NULL, then it will not be used. init - If non-NULL, an entry point that will be called before adding the library to the system. Registers are as follows: d0 = libAddr ;Your Library Address a0 = segList ;Your AmigaDOS segment list a6 = ExecBase ;Address of exec.library The result of the init function must be the library address, or NULL for failure. If NULL, the init point must manually deallocate the library base memory (based on the sizes stored in lib_PosSize and lib_NegSize). dSize - the size of the library data area, including the standard library node data. This must be at leas sizeof(struct Library). segList - pointer to an AmigaDOS SegList (segment list). This is passed to a library's init code, and is used later for removing the library from memory. RESULT library - the reference address of the library. This is the address used in references to the library, not the beginning of the memory area allocated. If the library vector table require more system memory than is available, this function will return NULL. SEE ALSO InitStruct, InitResident, exec/initializers.i exec.library/ObtainQuickVector exec.library/ObtainQuickVector NAME Function to obtain an install a Quick Interrupt vector (V39) SYNOPSIS vector=ObtainQuickVector(interruptCode) d0 a0 ULONG ObtainQuickVector(APTR); FUNCTION This function will install the code pointer into the quick interrupt vector it allocates and returns to you the interrupt vector that your Quick Interrupt system needs to use. This function may also return 0 if no vectors are available. Your hardware should be able to then fall back to using the shared interrupt server chain should this happen. The interrupt code is a direct connect to the physical interrupt. This means that it is the responsibility of your code to do all of the context saving/restoring required by interrupt code. Also, due to the performance of the interrupt controller, you may need to also watch for "false" interrupts. These are interrupts that come in just after a DISABLE. The reason this happens is because the interrupt may have been posted before the DISABLE hardware access is completed. For example: myInt: move.l d0,-(sp) ; Save d0... move.w _intenar,d0 ; Get interrupt enable state btst.l #INTB_INTEN,d0 ; Check if pending disable bne.s realInt ; If not, do real one... exitInt: move.l (sp)+,d0 ; Restore d0 rte ; Return from int... ; realInt: ; Now do your int code... d0 is already saved ; ALL other registers need to be saved if needed ; This includes a0/a1/d0/d1 as this is an interrupt ; and not a function call... ; bra.s exitInt ; Exit interrupt... If your interrupt will not play with system (OS) structures and your own structures are safe to play with you do not need to check for the disable. It is only needed for when the system is in disable but that "one last interrupt" still got through. NOTE This function was not implemented fully until V39. Due to a mis-cue it is not safe to call in V37 EXEC. (Sorry) INPUTS A pointer to your interrupt code. This code is not an EXEC interrupt but is dirrectly connected to the hardware interrupt. Thus, the interrupt code must not modify any registers and must return via an RTE. RESULTS The 8-bit vector number used for Zorro-III Quick Interrupts If it returns 0, no quick interrupt was allocatable. The device should at this point switch to using the shared interrupt server method. SEE ALSO exec.library/ObtainSemaphore exec.library/ObtainSemaphore NAME ObtainSemaphore -- gain exclusive access to a semaphore SYNOPSIS ObtainSemaphore(signalSemaphore) A0 void ObtainSemaphore(struct SignalSemaphore *); FUNCTION Signal semaphores are used to gain exclusive access to an object. ObtainSemaphore is the call used to gain this access. If another user currently has the semaphore locked the call will block until the object is available. If the current task already has locked the semaphore and attempts to lock it again the call will still succeed. A "nesting count" is incremented each time the current owning task of the semaphore calls ObtainSemaphore(). This counter is decremented each time ReleaseSemaphore() is called. When the counter returns to zero the semaphore is actually released, and the next waiting task is called. A queue of waiting tasks is maintained on the stacks of the waiting tasks. Each will be called in turn as soon as the current task releases the semaphore. Signal Semaphores are different than Procure()/Vacate() semaphores. The former requires less CPU time, especially if the semaphore is not currently locked. They require very little set up and user thought. The latter flavor of semaphore make no assumptions about how they are used -- they are completely general. Unfortunately they are not as efficient as signal semaphores, and require the locker to have done some setup before doing the call. INPUT signalSemaphore -- an initialized signal semaphore structure NOTE This function preserves all registers (see BUGS). BUGS Until V37, this function could destroy A0. SEE ALSO ObtainSemaphoreShared(), InitSemaphore(), ReleaseSemaphore(), AttemptSemaphore(), ObtainSemaphoreList(), Procure(), Vacate() exec.library/ObtainSemaphoreList exec.library/ObtainSemaphoreList NAME ObtainSemaphoreList -- get a list of semaphores. SYNOPSIS ObtainSemaphoreList(list) A0 void ObtainSemaphoreList(struct List *); FUNCTION Signal semaphores may be linked together into a list. This function takes a list of these semaphores and attempts to lock all of them at once. This call is preferable to applying ObtainSemaphore() to each element in the list because it attempts to lock all the elements simultaneously, and won't deadlock if someone is attempting to lock in some other order. This function assumes that only one task at a time will attempt to lock the entire list of semaphores. In other words, there needs to be a higher level lock (perhaps another signal semaphore...) that is used before someone attempts to lock the semaphore list via ObtainSemaphoreList(). Note that deadlocks may result if this call is used AND someone attempts to use ObtainSemaphore() to lock more than one semaphore on the list. If you wish to lock more than semaphore (but not all of them) then you should obtain the higher level lock (see above) INPUT list -- a list of signal semaphores SEE ALSO ObtainSemaphoreShared(), InitSemaphore(), ReleaseSemaphore(), AttemptSemaphore(), ObtainSemaphoreShared(), Procure(), Vacate() exec.library/ObtainSemaphoreShared exec.library/ObtainSemaphoreShared NAME ObtainSemaphoreShared -- gain shared access to a semaphore (V36) SYNOPSIS ObtainSemaphoreShared(signalSemaphore) a0 void ObtainSemaphoreShared(struct SignalSemaphore *); FUNCTION A lock on a signal semaphore may either be exclusive, or shared. Exclusive locks are granted by the ObtainSemaphore() and AttemptSemaphore() functions. Shared locks are granted by ObtainSemaphoreShared(). Calls may be nested. Any number of tasks may simultaneously hold a shared lock on a semaphore. Only one task may hold an exclusive lock. A typical application is a list that is often read, but only occasionally written to. Any exlusive locker will be held off until all shared lockers release the semaphore. Likewise, if an exlusive lock is held, all potential shared lockers will block until the exclusive lock is released. All shared lockers are restarted at the same time. EXAMPLE ObtainSemaphoreShared(ss); /* read data */ ReleaseSemaohore(ss); ObtainSemaphore(ss); /* modify data */ ReleaseSemaohore(ss); NOTES While this function was added for V36, the feature magically works with all older semaphore structures. A task owning a shared lock must not attempt to get an exclusive lock on the same semaphore. Starting in V39, if the caller already has an exclusive lock on the semaphore it will return with another nesting of the lock. Pre-V39 this would cause a deadlock. For pre-V39 use, you can use the following workaround: /* Try to get the shared semaphore */ if (!AttemptSemaphoreShared(ss)) { /* Check if we can get the exclusive version */ if (!AttemptSemaphore(ss)) { /* Oh well, wait for the shared lock */ ObtainSemaphoreShared(ss)); } } : : ReleaseSemaphore(ss); INPUT signalSemaphore -- an initialized signal semaphore structure NOTE This call is guaranteed to preserve all registers, starting with V37 exec. RESULT SEE ALSO ObtainSemaphore(), InitSemaphore(), ReleaseSemaphore(), AttemptSemaphore(), ObtainSemaphoreList(), Procure(), Vacate() exec.library/OldOpenLibrary exec.library/OldOpenLibrary NAME OldOpenLibrary -- obsolete OpenLibrary SYNOPSIS library = OldOpenLibrary(libName) D0 A1 struct Library *OldOpenLibrary(APTR); FUNCTION The 1.0 release of the Amiga system had an incorrect version of OpenLibrary that did not check the version number during the library open. This obsolete function is provided so that object code compiled using a 1.0 system will still run. This exactly the same as "OpenLibrary(libName,0L);" INPUTS libName - the name of the library to open RESULTS library - a library pointer for a successful open, else zero SEE ALSO CloseLibrary exec.library/OpenDevice exec.library/OpenDevice NAME OpenDevice -- gain access to a device SYNOPSIS error = OpenDevice(devName, unitNumber, iORequest, flags) D0 A0 D0 A1 D1 BYTE OpenDevice(STRPTR,ULONG,struct IORequest *,ULONG); FUNCTION This function opens the named device/unit and initializes the given I/O request block. Specific documentation on opening procedures may come with certain devices. The device may exist in memory, or on disk; this is transparent to the OpenDevice caller. A full path name for the device name is legitimate. For example "test:devs/fred.device". This allows the use of custom devices without requiring the user to copy the device into the system's DEVS: directory. NOTES All calls to OpenDevice should have matching calls to CloseDevice! Devices on disk cannot be opened until after DOS has been started. As of V36 tasks can safely call OpenDevice, though DOS may open system requesters (e.g., asking the user to insert the Workbench disk if DEVS: is not online). You must call this function from a DOS Process if you want to turn off DOS requesters. INPUTS devName - requested device name unitNumber - the unit number to open on that device. The format of the unit number is device specific. If the device does not have separate units, send a zero. iORequest - the I/O request block to be returned with appropriate fields initialized. flags - additional driver specific information. This is sometimes used to request opening a device with exclusive access. RESULTS error - Returns a sign-extended copy of the io_Error field of the IORequest. Zero if successful, else an error code is returned. BUGS AmigaDOS file names are not case sensitive, but Exec lists are. If the library name is specified in a different case than it exists on disk, unexpected results may occur. Prior to V36, tasks could not make OpenDevice calls requiring disk access (since tasks are not allowed to make dos.library calls). Now OpenDevice is protected from tasks. SEE ALSO CloseDevice, DoIO, SendIO, CheckIO, AbortIO, WaitIO exec.library/OpenLibrary exec.library/OpenLibrary NAME OpenLibrary -- gain access to a library SYNOPSIS library = OpenLibrary(libName, version) D0 A1 D0 struct Library *OpenLibrary(STRPTR, ULONG); FUNCTION This function returns a pointer to a library that was previously installed into the system. If the requested library is exists, and if the library version is greater than or equal to the requested version, then the open will succeed. The library may exist in memory, or on disk; this is transparent to the OpenLibrary caller. Only Processes are allowed to call OpenLibrary (since OpenLibrary may in turn call dos.library). A full path name for the library name is legitimate. For example "wp:libs/wp.library". This allows the use of custom libraries without requiring the user to copy the library into the system's LIBS: directory. NOTES All calls to OpenLibrary should have matching calls to CloseLibrary! Libraries on disk cannot be opened until after DOS has been started. As of V36 tasks can safely call OpenLibrary, though DOS may open system requesters (e.g., asking the user to insert the Workbench disk if LIBS: is not online). You must call this function from a DOS Process if you want to turn off DOS requesters. INPUTS libName - the name of the library to open version - the version of the library required. RESULTS library - a library pointer for a successful open, else zero BUGS AmigaDOS file names are not case sensitive, but Exec lists are. If the library name is specified in a different case than it exists on disk, unexpected results may occur. Prior to V36, tasks could not make OpenLibrary calls requiring disk access (since tasks are not allowed to make dos.library calls). Now OpenLibrary is protected from tasks. The version number of the resident tag in disk based library must match the version number of the library, or V36 may fail to load it. SEE ALSO CloseLibrary exec.library/OpenResource exec.library/OpenResource NAME OpenResource -- gain access to a resource SYNOPSIS resource = OpenResource(resName) D0 A1 APTR OpenResource(STRPTR); FUNCTION This function returns a pointer to a resource that was previously installed into the system. There is no CloseResource() function. INPUTS resName - the name of the resource requested. RESULTS resource - if successful, a resource pointer, else NULL exec.library/Permit exec.library/Permit NAME Permit -- permit task rescheduling. SYNOPSIS Permit() void Permit(void); FUNCTION Allow other tasks to be scheduled to run by the dispatcher, after a matching Forbid() has been executed. RESULTS Other tasks will be rescheduled as they are ready to run. In order to restore normal task rescheduling, the programmer must execute exactly one call to Permit() for every call to Forbid(). NOTE This call is guaranteed to preserve all registers. SEE ALSO Forbid, Disable, Enable exec.library/Procure exec.library/Procure NAME Procure -- bid for a semaphore (V39) SYNOPSIS Procure(semaphore, bidMessage) A0 A1 VOID Procure(struct SignalSemaphore *, struct SemaphoreMessage *); FUNCTION This function is used to obtain a semaphore in an async manner. Like ObtainSemaphore(), it will obtain a SignalSemaphore for you but unlike ObtainSemaphore(), you will not block until you get the semaphore. Procure() will just post a request for the semaphore and will return. When the semaphore is available (which could be at any time) the bidMessage will ReplyMsg() and you will own the semaphore. This lets you wait on multiple semaphores at once and to continue processing while waiting for the semaphore. NOTE: Pre-V39, Procure() and Vacate() did not work correctly. They also did not operate on SignalSemaphore semaphores. Old (and broken) MessageSemaphore use as of V39 will no longer work. INPUT semaphore - The SignalSemaphore that you wish to Procure() bidMessage- The SemaphoreMessage that you wish replied when you obtain access to the semaphore. The message's ssm_Semaphore field will point at the semaphore that was obtained. If the ssm_Semaphore field is NULL, the Procure() was aborted via Vacate(). The mn_ReplyPort field of the message must point to a valid message port. To obtain a shared semaphore, the ln_Name field must be set to 1. For an exclusive lock, the ln_Name field must be 0. No other values are valid. BUGS Before V39, Procure() and Vacate() used a different semaphore system that was very broken. This new system is only available as of V39 even though the LVOs are the same. SEE ALSO ObtainSemaphoreShared(), InitSemaphore(), ReleaseSemaphore(), AttemptSemaphore(), ObtainSemaphoreList(), Vacate(), ObtainSemaphore() exec.library/PutMsg exec.library/PutMsg NAME PutMsg -- put a message to a message port SYNOPSIS PutMsg(port, message) A0 A1 void PutMsg(struct MsgPort *, struct Message *); FUNCTION This function attaches a message to the end of a given message port. It provides a fast, non-copying message sending mechanism. Messages can be attached to only one port at a time. The message body can be of any size or form. Because messages are not copied, cooperating tasks share the same message memory. The sender task must not recycle the message until it has been replied by the receiver. Of course this depends on the message handling conventions setup by the involved tasks. If the ReplyPort field is non-zero, when the message is replied by the receiver, it will be sent back to that port. Any one of the following actions can be set to occur when a message is put: 1. no special action 2. signal a given task (specified by MP_SIGTASK) 3. cause a software interrupt (specified by MP_SIGTASK) The action is selected depending on the value found in the MP_FLAGS of the destination port. IMPLEMENTATION 1. Sets the LN_TYPE field to "NT_MESSAGE". 2. Attaches the message to the destination port. 3. Performs the specified arrival action at the destination. INPUT port - pointer to a message port message - pointer to a message SEE ALSO GetMsg, ReplyMsg, exec/ports.h exec.library/RawDoFmt exec.library/RawDoFmt NAME RawDoFmt -- format data into a character stream. SYNOPSIS NextData = RawDoFmt(FormatString, DataStream, PutChProc, PutChData); d0 a0 a1 a2 a3 APTR RawDoFmt(STRPTR,APTR,void (*)(),APTR); FUNCTION perform "C"-language-like formatting of a data stream, outputting the result a character at a time. Where % formatting commands are found in the FormatString, they will be replaced with the corresponding element in the DataStream. %% must be used in the string if a % is desired in the output. Under V36, RawDoFmt() returns a pointer to the end of the DataStream (The next argument that would have been processed). This allows multiple formatting passes to be made using the same data. INPUTS FormatString - a "C"-language-like NULL terminated format string, with the following supported % options: %[flags][width.limit][length]type flags - only one allowed. '-' specifies left justification. width - field width. If the first character is a '0', the field will be padded with leading 0's. . - must follow the field width, if specified limit - maximum number of characters to output from a string. (only valid for %s). length - size of input data defaults to WORD for types d, x, and c, 'l' changes this to long (32-bit). type - supported types are: b - BSTR, data is 32-bit BPTR to byte count followed by a byte string, or NULL terminated byte string. A NULL BPTR is treated as an empty string. (Added in V36 exec) d - decimal u - unsigned decimal (Added in V37 exec) x - hexadecimal s - string, a 32-bit pointer to a NULL terminated byte string. In V36, a NULL pointer is treated as an empty string c - character DataStream - a stream of data that is interpreted according to the format string. Often this is a pointer into the task's stack. PutChProc - the procedure to call with each character to be output, called as: PutChProc(Char, PutChData); D0-0:8 A3 the procedure is called with a NULL Char at the end of the format string. PutChData - a value that is passed through to the PutChProc procedure. This is untouched by RawDoFmt, and may be modified by the PutChProc. EXAMPLE ; ; Simple version of the C "sprintf" function. Assumes C-style ; stack-based function conventions. ; ; long eyecount; ; eyecount=2; ; sprintf(string,"%s have %ld eyes.","Fish",eyecount); ; ; would produce "Fish have 2 eyes." in the string buffer. ; XDEF _sprintf XREF _AbsExecBase XREF _LVORawDoFmt _sprintf: ; ( ostring, format, {values} ) movem.l a2/a3/a6,-(sp) move.l 4*4(sp),a3 ;Get the output string pointer move.l 5*4(sp),a0 ;Get the FormatString pointer lea.l 6*4(sp),a1 ;Get the pointer to the DataStream lea.l stuffChar(pc),a2 move.l _AbsExecBase,a6 jsr _LVORawDoFmt(a6) movem.l (sp)+,a2/a3/a6 rts ;------ PutChProc function used by RawDoFmt ----------- stuffChar: move.b d0,(a3)+ ;Put data to output string rts WARNING This Amiga ROM function formats word values in the data stream. If your compiler defaults to longs, you must add an "l" to your % specifications. This can get strange for characters, which might look like "%lc". The result of RawDoFmt() is *ONLY* valid in V36 and later releases of EXEC. Pre-V36 versions of EXEC have "random" return values. SEE ALSO Documentation on the C language "printf" call in any C language reference book. exec.library/ReleaseSemaphore exec.library/ReleaseSemaphore NAME ReleaseSemaphore -- make signal semaphore available to others SYNOPSIS ReleaseSemaphore(signalSemaphore) A0 void ReleaseSemaphore(struct SignalSemaphore *); FUNCTION ReleaseSemaphore() is the inverse of ObtainSemaphore(). It makes the semaphore lockable to other users. If tasks are waiting for the semaphore and this this task is done with the semaphore then the next waiting task is signalled. Each ObtainSemaphore() call must be balanced by exactly one ReleaseSemaphore() call. This is because there is a nesting count maintained in the semaphore of the number of times that the current task has locked the semaphore. The semaphore is not released to other tasks until the number of releases matches the number of obtains. Needless to say, havoc breaks out if the task releases more times than it has obtained. INPUT signalSemaphore -- an initialized signal semaphore structure NOTE This call is guaranteed to preserve all registers. SEE ALSO InitSemaphore(), ObtainSemaphore(), ObtainSemaphoreShared() exec.library/ReleaseSemaphoreList exec.library/ReleaseSemaphoreList NAME ReleaseSemaphoreList -- make a list of semaphores available SYNOPSIS ReleaseSemaphoreList(list) A0 void ReleaseSemaphoreList(struct List *); FUNCTION ReleaseSemaphoreList() is the inverse of ObtainSemaphoreList(). It releases each element in the semaphore list. Needless to say, havoc breaks out if the task releases more times than it has obtained. INPUT list -- a list of signal semaphores SEE ALSO ObtainSemaphoreList() exec.library/RemDevice exec.library/RemDevice NAME RemDevice -- remove a device from the system SYNOPSIS RemDevice(device) A1 void RemDevice(struct Device *); FUNCTION This function calls the device's EXPUNGE vector, which requests that a device delete itself. The device may refuse to do this if it is busy or currently open. This is not typically called by user code. There are certain, limited circumstances where it may be appropriate to attempt to specifically flush a certain device. Example: /* Attempts to flush the named device out of memory. */ #include <exec/types.h> #include <exec/execbase.h> void FlushDevice(name) STRPTR name; { struct Device *result; Forbid(); if(result=(struct Device *)FindName(&SysBase->DeviceList,name)) RemDevice(result); Permit(); } INPUTS device - pointer to a device node SEE ALSO AddLibrary exec.library/RemHead exec.library/RemHead NAME RemHead -- remove the head node from a list SYNOPSIS node = RemHead(list) D0 A0 struct Node *RemHead(struct List *); FUNCTION Get a pointer to the head node and remove it from the list. Assembly programmers may prefer to use the REMHEAD macro from "exec/lists.i". WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS list - a pointer to the target list header RESULT node - the node removed or zero when empty list SEE ALSO AddHead, AddTail, Enqueue, Insert, Remove, RemTail exec.library/RemIntServer exec.library/RemIntServer NAME RemIntServer -- remove an interrupt server from a server chain SYNOPSIS RemIntServer(intNum, interrupt) D0 A1 void RemIntServer(ULONG,struct Interrupt *); FUNCTION This function removes an interrupt server node from the given server chain. If this server was the last one on this chain, interrupts for this chain are disabled. INPUTS intNum - the Paula interrupt bit (0..14) interrupt - pointer to an interrupt server node BUGS Before V36 Kickstart, the feature that disables the interrupt would not function. For most server chains this does not cause a problem. SEE ALSO AddIntServer, hardware/intbits.h exec.library/RemLibrary exec.library/RemLibrary NAME RemLibrary -- remove a library from the system SYNOPSIS RemLibrary(library) A1 void RemLibrary(struct Library *); FUNCTION This function calls the library's EXPUNGE vector, which requests that a library delete itself. The library may refuse to do this if it is busy or currently open. This is not typically called by user code. There are certain, limited circumstances where it may be appropriate to attempt to specifically flush a certain Library. Example: /* Attempts to flush the named library out of memory. */ #include <exec/types.h> #include <exec/execbase.h> void FlushLibrary(name) STRPTR name; { struct Library *result; Forbid(); if(result=(struct Library *)FindName(&SysBase->LibList,name)) RemLibrary(result); Permit(); } INPUTS library - pointer to a library node structure exec.library/RemMemHandler exec.library/RemMemHandler NAME RemMemHandler - Remove low memory handler from exec (V39) SYNOPSIS RemMemHandler(memHandler) A1 VOID RemMemHandler(struct Interrupt *); FUNCTION This function removes the low memory handler from the system. This function can be called from within a handler. If removing oneself, it is important that the handler returns MEM_ALL_DONE. NOTE When removing a handler, the handler may be called until this function returns. Thus, the handler must still be valid until then. INPUTS memHandler - Pointer to a handler added with AddMemHandler() SEE ALSO AddMemHandler, exec/interrupts.i exec.library/Remove exec.library/Remove NAME Remove -- remove a node from a list SYNOPSIS Remove(node) A1 void Remove(struct Node *); FUNCTION Unlink a node from whatever list it is in. Nodes that are not part of a list must not be passed to this function! Assembly programmers may prefer to use the REMOVE macro from "exec/lists.i". WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS node - the node to remove SEE ALSO AddHead, AddTail, Enqueue, Insert, RemHead, RemTail exec.library/RemPort exec.library/RemPort NAME RemPort -- remove a message port from the system SYNOPSIS RemPort(port) A1 void RemPort(struct MsgPort *); FUNCTION This function removes a message port structure from the system's message port list. Subsequent attempts to rendezvous by name with this port will fail. INPUTS port - pointer to a message port SEE ALSO AddPort, FindPort exec.library/RemResource exec.library/RemResource NAME RemResource -- remove a resource from the system SYNOPSIS RemResource(resource) A1 void RemResource(APTR); FUNCTION This function removes an existing resource from the system resource list. There must be no outstanding users of the resource. INPUTS resource - pointer to a resource node SEE ALSO AddResource exec.library/RemSemaphore exec.library/RemSemaphore NAME RemSemaphore -- remove a signal semaphore from the system SYNOPSIS RemSemaphore(signalSemaphore) A1 void RemSemaphore(struct SignalSemaphore *); FUNCTION This function removes a signal semaphore structure from the system's signal semaphore list. Subsequent attempts to rendezvous by name with this semaphore will fail. INPUTS signalSemaphore -- an initialized signal semaphore structure SEE ALSO AddSemaphore, FindSemaphore exec.library/RemTail exec.library/RemTail NAME RemTail -- remove the tail node from a list SYNOPSIS node = RemTail(list) D0 A0 struct Node *RemTail(struct List *); FUNCTION Remove the last node from a list, and return a pointer to it. If the list is empty, return zero. Assembly programmers may prefer to use the REMTAIL macro from "exec/lists.i". WARNING This function does not arbitrate for access to the list. The calling task must be the owner of the involved list. INPUTS list - a pointer to the target list header RESULT node - the node removed or zero when empty list SEE ALSO AddHead, AddTail, Enqueue, Insert, Remove, RemHead, RemTail exec.library/RemTask exec.library/RemTask NAME RemTask -- remove a task from the system SYNOPSIS RemTask(task) A1 void RemTask(struct Task *); FUNCTION This function removes a task from the system. Deallocation of resources should have been performed prior to calling this function. Removing some other task is very dangerous. Generally is is best to arrange for tasks to call RemTask(0L) on themselves. RemTask will automagically free any memory lists attached to the task's TC_MEMENTRY list. INPUTS task - pointer to the task node representing the task to be removed. A zero value indicates self removal, and will cause the next ready task to begin execution. BUGS Before V36 if RemTask() was called on a task other than the current task, and that task was created with amiga.lib/CreateTask, there was a slight chance of a crash. The problem can be hidden by bracketing RemTask() with Forbid()/Permit(). SEE ALSO AddTask, exec/AllocEntry, amiga.lib/DeleteTask exec.library/ReplyMsg exec.library/ReplyMsg NAME ReplyMsg -- put a message to its reply port SYNOPSIS ReplyMsg(message) A1 void ReplyMsg(struct Message *); FUNCTION This function sends a message to its reply port. This is usually done when the receiver of a message has finished and wants to return it to the sender (so that it can be re-used or deallocated, whatever). This call may be made from interrupts. INPUT message - a pointer to the message IMPLEMENTATION 1> Places "NT_REPLYMSG" into LN_TYPE. 2> Puts the message to the port specified by MN_REPLYPORT If there is no replyport, sets LN_TYPE to "NT_FREEMSG" (use this feature only with extreme care). SEE ALSO GetMsg, PutMsg, exec/ports.h exec.library/SendIO exec.library/SendIO NAME SendIO -- initiate an I/O command SYNOPSIS SendIO(iORequest) A1 void SendIO(struct IORequest *); FUNCTION This function requests the device driver start processing the given I/O request. The device will return control without waiting for the I/O to complete. The io_Flags field of the IORequest will be set to zero before the request is sent. See BeginIO() for more details. INPUTS iORequest - pointer to an I/O request, or a device specific extended IORequest. SEE ALSO DoIO, CheckIO, WaitIO, AbortIO exec.library/SetExcept exec.library/SetExcept NAME SetExcept -- define certain signals to cause exceptions SYNOPSIS oldSignals = SetExcept(newSignals, signalMask) D0 D0 D1 ULONG SetExcept(ULONG,ULONG); FUNCTION This function defines which of the task's signals will cause a private task exception. When any of the signals occurs the task's exception handler will be dispatched. If the signal occurred prior to calling SetExcept, the exception will happen immediately. The user function pointed to by the task's tc_ExceptCode gets called as: newExcptSet = <exceptCode>(signals, exceptData),SysBase D0 D0 A1 A6 signals - The set of signals that caused this exception. These Signals have been disabled from the current set of signals that can cause an exception. exceptData - A copy of the task structure tc_ExceptData field. newExcptSet - The set of signals in NewExceptSet will be re- enabled for exception generation. Usually this will be the same as the Signals that caused the exception. INPUTS newSignals - the new values for the signals specified in signalMask. signalMask - the set of signals to be effected RESULTS oldSignals - the prior exception signals EXAMPLE Get the current state of all exception signals: SetExcept(0,0) Change a few exception signals: SetExcept($1374,$1074) SEE ALSO Signal, SetSignal exec.library/SetFunction exec.library/SetFunction NAME SetFunction -- change a function vector in a library SYNOPSIS oldFunc = SetFunction(library, funcOffset, funcEntry) D0 A1 A0.W D0 APTR SetFunction(struct Library *,LONG,APTR); FUNCTION SetFunction is a functional way of changing where vectors in a library point. They are changed in such a way that the checksumming process will never falsely declare a library to be invalid. WARNING If you use SetFunction on a function that can be called from interrupts, you are obligated to provide your own arbitration. NOTE SetFunction cannot be used on non-standard libraries like pre-V36 dos.library. Here you must manually Forbid(), preserve all 6 original bytes, set the new vector, SumLibrary(), then Permit(). INPUTS library - a pointer to the library to be changed funcOffset - the offset of the function to be replaced funcEntry - pointer to new function RESULTS oldFunc - pointer to the old function that was just replaced exec.library/SetIntVector exec.library/SetIntVector NAME SetIntVector -- set a new handler for a system interrupt vector SYNOPSIS oldInterrupt = SetIntVector(intNumber, interrupt) D0 D0 A1 struct Interrupt *SetIntVector(ULONG, struct Interrupt *); FUNCTION This function provides a mechanism for setting the system interrupt vectors. These are non-sharable; setting a new interrupt handler disconnects the old one. Installed handlers are responsible for processing, enabling and clearing the interrupt. Note that interrupts may have been left in any state by the previous code. The IS_CODE and IS_DATA pointers of the Interrupt structure will be copied into a private place by Exec. A pointer to the previously installed Interrupt structure is returned. When the system calls the specified interrupt code, the registers are setup as follows: D0 - scratch D1 - scratch (on entry: active interrupts -> equals INTENA & INTREQ) A0 - scratch (on entry: pointer to base of custom chips for fast indexing) A1 - scratch (on entry: Interrupt's IS_DATA pointer) A5 - jump vector register (scratch on call) A6 - Exec library base pointer (scratch on call) all other registers must be preserved INPUTS intNum - the Paula interrupt bit number (0..14). Only non-chained interrupts should be set. Use AddIntServer() for server chains. interrupt - a pointer to an Interrupt structure containing the handler's entry point and data segment pointer. A NULL interrupt pointer will remove the current interrupt and set illegal values for IS_CODE and IS_DATA. By convention, the LN_NAME of the interrupt structure must point a descriptive string so that other users may identify who currently has control of the interrupt. RESULT A pointer to the prior interrupt structure which had control of this interrupt. SEE ALSO AddIntServer(),exec/interrupts.i,hardware/intbits.i exec.library/SetSignal exec.library/SetSignal NAME SetSignal -- define the state of this task's signals SYNOPSIS oldSignals = SetSignal(newSignals, signalMask) D0 D0 D1 ULONG SetSignal(ULONG,ULONG); FUNCTION This function can query or modify the state of the current task's received signal mask. Setting the state of signals is considered dangerous. Reading the state of signals is safe. INPUTS newSignals - the new values for the signals specified in signalSet. signalMask - the set of signals to be affected. RESULTS oldSignals - the prior values for all signals EXAMPLES Get the current state of all signals: SetSignal(0L,0L); Clear the CTRL-C signal: SetSignal(0L,SIGBREAKF_CTRL_C); Check if the CTRL-C signal was pressed: #include <libraries/dos.h> /* Check & clear CTRL_C signal */ if(SetSignal(0L,SIGBREAKF_CTRL_C) & SIGBREAKF_CTRL_C) { printf("CTRL-C pressed!\n"); } SEE ALSO Signal, Wait exec.library/SetSR exec.library/SetSR NAME SetSR -- get and/or set processor status register SYNOPSIS oldSR = SetSR(newSR, mask) D0 D0 D1 ULONG SetSR(ULONG, ULONG); FUNCTION This function provides a means of modifying the CPU status register in a "safe" way (well, how safe can a function like this be anyway?). This function will only affect the status register bits specified in the mask parameter. The prior content of the entire status register is returned. INPUTS newSR - new values for bits specified in the mask. All other bits are not effected. mask - bits to be changed RESULTS oldSR - the entire status register before new bits EXAMPLES To get the current SR: currentSR = SetSR(0,0); To change the processor interrupt level to 3: oldSR = SetSR($0300,$0700); Set processor interrupts back to prior level: SetSR(oldSR,$0700); exec.library/SetTaskPri exec.library/SetTaskPri NAME SetTaskPri -- get and set the priority of a task SYNOPSIS oldPriority = SetTaskPri(task, priority) D0-0:8 A1 D0-0:8 BYTE SetTaskPri(struct Task *,LONG); FUNCTION This function changes the priority of a task regardless of its state. The old priority of the task is returned. A reschedule is performed, and a context switch may result. To change the priority of the currently running task, pass the result of FindTask(0); as the task pointer. INPUTS task - task to be affected priority - the new priority for the task RESULT oldPriority - the tasks previous priority exec.library/Signal exec.library/Signal NAME Signal -- signal a task SYNOPSIS Signal(task, signals) A1 D0 void Signal(struct Task *,ULONG); FUNCTION This function signals a task with the given signals. If the task is currently waiting for one or more of these signals, it will be made ready and a reschedule will occur. If the task is not waiting for any of these signals, the signals will be posted to the task for possible later use. A signal may be sent to a task regardless of whether it is running, ready, or waiting. This function is considered "low level". Its main purpose is to support multiple higher level functions like PutMsg. This function is safe to call from interrupts. INPUT task - the task to be signalled signals - the signals to be sent SEE ALSO Wait, SetSignal exec.library/StackSwap exec.library/StackSwap NAME StackSwap - EXEC supported method of replacing task's stack (V37) SYNOPSIS StackSwap(newStack) A0 VOID StackSwap(struct StackSwapStruct *); FUNCTION This function will, in an EXEC supported manner, swap the stack of your task with the given values in StackSwap. The StackSwapStruct structure will then contain the values of the old stack such that the old stack can be restored. This function is new in V37. NOTE If you do a stack swap, only the new stack is set up. This function does not copy the stack or do anything else other than set up the new stack for the task. It is generally required that you restore your stack before exiting. INPUTS newStack - A structure that contains the values for the new upper and lower stack bounds and the new stack pointer. This structure will have its values replaced by those in you task such that you can restore the stack later. RESULTS newStack - The structure will now contain the old stack. This means that StackSwap(foo); StackSwap(foo); will effectively do nothing. SEE ALSO AddTask, RemTask, exec/tasks.h exec.library/SumKickData exec.library/SumKickData NAME SumKickData -- compute the checksum for the Kickstart delta list SYNOPSIS checksum = SumKickData() D0 ULONG SumKickData(void); FUNCTION The Amiga system has some ROM (or Kickstart) resident code that provides the basic functions for the machine. This code is unchangeable by the system software. This function is part of a support system to modify parts of the ROM. The ROM code is linked together at run time via ROMTags (also known as Resident structures, defined in exec/resident.h). These tags tell Exec's low level boot code what subsystems exist in which regions of memory. The current list of ROMTags is contained in the ResModules field of ExecBase. By default this list contains any ROMTags found in the address ranges $F80000-$FFFFFF and $F00000-$F7FFFF. There is also a facility to selectively add or replace modules to the ROMTag list. These modules can exist in RAM, and the memory they occupy will be deleted from the memory free list during the boot process. SumKickData() plays an important role in this run-time modification of the ROMTag array. Three variables in ExecBase are used in changing the ROMTag array: KickMemPtr, KickTagPtr, and KickCheckSum. KickMemPtr points to a linked list of MemEntry structures. The memory that these MemEntry structures reference will be allocated (via AllocAbs) at boot time. The MemEntry structure itself must also be in the list. KickTagPtr points to a long-word array of the same format as the ResModules array. The array has a series of pointers to ROMTag structures. The array is either NULL terminated, or will have an entry with the most significant bit (bit 31) set. The most significant bit being set says that this is a link to another long-word array of ROMTag entries. This new array's address can be found by clearing bit 31. KickCheckSum has the result of SumKickData(). It is the checksum of both the KickMemPtr structure and the KickTagPtr arrays. If the checksum does not compute correctly then both KickMemPtr and KickTagPtr will be ignored. If all the memory referenced by KickMemPtr can't be allocated then KickTagPtr will be ignored. There is one more important caveat about adding ROMTags. All this ROMTag magic is run very early on in the system -- before expansion memory is added to the system. Therefore any memory in this additional ROMTag area must be addressable at this time. This means that your ROMTag code, MemEntry structures, and resident arrays cannot be in expansion memory. There are two regions of memory that are acceptable: one is chip memory, and the other is "Ranger" memory (memory in the range between $C00000-$D80000). Remember that changing an existing ROMTag entry falls into the "heavy magic" category -- be very careful when doing it. The odd are that you will blow yourself out of the water. NOTE SumKickData was introduced in the 1.2 release RESULT Value to be stuffed into ExecBase->KickCheckSum. WARNING After writing to KickCheckSum, you should push the data cache. This prevents potential problems with large copyback style caches. A call to CacheClearU will do fine. SEE ALSO InitResident, FindResident exec.library/SumLibrary exec.library/SumLibrary NAME SumLibrary -- compute and check the checksum on a library SYNOPSIS SumLibrary(library) A1 void SumLibrary(struct Library *); FUNCTION SumLibrary computes a new checksum on a library. It can also be used to check an old checksum. If an old checksum does not match, and the library has not been marked as changed, then the system will call Alert(). This call could also be periodically made by some future system-checking task. INPUTS library - a pointer to the library to be changed NOTE An alert will occur if the checksum fails. SEE ALSO SetFunction exec.library/SuperState exec.library/SuperState NAME SuperState -- enter supervisor state with user stack SYNOPSIS oldSysStack = SuperState() D0 APTR SuperState(void); FUNCTION Enter supervisor mode while running on the user's stack. The user still has access to user stack variables. Be careful though, the user stack must be large enough to accommodate space for all interrupt data -- this includes all possible nesting of interrupts. This function does nothing when called from supervisor state. RESULTS oldSysStack - system stack pointer; save this. It will come in handy when you return to user state. If the system is already in supervisor mode, oldSysStack is zero. SEE ALSO UserState/Supervisor exec.library/Supervisor exec.library/Supervisor NAME Supervisor -- trap to a short supervisor mode function SYNOPSIS result = Supervisor(userFunc) Rx A5 ULONG Supervisor(void *); FUNCTION Allow a normal user-mode program to execute a short assembly language function in the supervisor mode of the processor. Supervisor() does not modify or save registers; the user function has full access to the register set. All rules that apply to interrupt code must be followed. In addition, no system calls are permitted. The function must end with an RTE instruction. EXAMPLE ;Obtain the Exception Vector base. 68010 or greater only! MOVECtrap: movec.l VBR,d0 ;$4e7a,$0801 rte INPUTS userFunc - A pointer to a short assembly language function ending in RTE. The function has full access to the register set. RESULTS result - Whatever values the userFunc left in the registers. SEE ALSO SuperState,UserState exec.library/TypeOfMem exec.library/TypeOfMem NAME TypeOfMem -- determine attributes of a given memory address SYNOPSIS attributes = TypeOfMem(address) D0 A1 ULONG TypeOfMem(void *); FUNCTION Given a RAM memory address, search the system memory lists and return its memory attributes. The memory attributes are similar to those specified when the memory was first allocated: (eg. MEMF_CHIP and MEMF_FAST). This function is usually used to determine if a particular block of memory is within CHIP space. If the address is not in known-space, a zero will be returned. (Anything that is not RAM, like the ROM or expansion area, will return zero. Also the first few bytes of a memory area are used up by the MemHeader.) INPUT address - a memory address RESULT attributes - a long word of memory attribute flags. If the address is not in known RAM, zero is returned. SEE ALSO AllocMem() exec.library/UserState exec.library/UserState NAME UserState -- return to user state with user stack SYNOPSIS UserState(sysStack) D0 void UserState(APTR); FUNCTION Return to user state with user stack, from supervisor state with user stack. This function is normally used in conjunction with the SuperState function above. This function must not be called from the user state. INPUT sysStack - supervisor stack pointer BUGS This function is broken in V33/34 Kickstart. Fixed in V1.31 setpatch. SEE ALSO SuperState/Supervisor exec.library/Vacate exec.library/Vacate NAME Vacate -- release a bitMessage from Procure() (V39) SYNOPSIS Vacate(semaphore, bidMessage) A0 A1 void Vacate(struct SignalSemaphore *,struct SemaphoreMessage *); FUNCTION This function can be used to release a semaphore obtained via Procure(). However, the main purpose for this call is to be able to remove a bid for a semaphore that has not yet responded. This is required when a Procure() was issued and the program no longer needs to get the semaphore and wishes to cancel the Procure() request. The canceled request will be replied with the ssm_Semaphore field set to NULL. If you own the semaphore, the message was already replied and only the ssm_Semaphore field will be cleared. NOTE: Pre-V39, Procure() and Vacate() did not work correctly. They also did not operate on SignalSemaphore semaphores. Old (and broken) MessageSemaphore use as of V39 will no longer work. INPUT semaphore - The SignalSemaphore that you wish to Vacate() bidMessage- The SemaphoreMessage that you wish to abort. The message's ssm_Semaphore field will be cleared. The message will be replied if it is still on the waiting list. If it is not on the waiting list, it is assumed that the semaphore is owned and it will be released. BUGS Before V39, Procure() and Vacate() used a different semaphore system that was very broken. This new system is only available as of V39 even though the LVOs are the same. SEE ALSO ObtainSemaphoreShared(), InitSemaphore(), ReleaseSemaphore(), AttemptSemaphore(), ObtainSemaphoreList(), Procure(), ObtainSemaphore() exec.library/Wait exec.library/Wait NAME Wait -- wait for one or more signals SYNOPSIS signals = Wait(signalSet) D0 D0 ULONG Wait(ULONG); FUNCTION This function will cause the current task to suspend waiting for one or more signals. When one or more of the specified signals occurs, the task will return to the ready state, and those signals will be cleared. If a signal occurred prior to calling Wait(), the wait condition will be immediately satisfied, and the task will continue to run without delay. CAUTION This function cannot be called while in supervisor mode or interrupts! This function will break the action of a Forbid() or Disable() call. INPUT signalSet - The set of signals for which to wait. Each bit represents a particular signal. RESULTS signals - the set of signals that were active exec.library/WaitIO exec.library/WaitIO NAME WaitIO -- wait for completion of an I/O request SYNOPSIS error = WaitIO(iORequest) D0 A1 BYTE WaitIO(struct IORequest *); FUNCTION This function waits for the specified I/O request to complete, then removes it from the replyport. If the I/O has already completed, this function will return immediately. This function should be used with care, as it does not return until the I/O request completes; if the I/O never completes, this function will never return, and your task will hang. If this situation is a possibility, it is safer to use the Wait() function. Wait() will return return when any of a specified set of signal is received. This is how I/O timeouts can be properly handled. WARNING If this IORequest was "Quick" or otherwise finished BEFORE this call, this function drops though immediately, with no call to Wait(). A side effect is that the signal bit related the port may remain set. Expect this. When removing a known complete IORequest from a port, WaitIO() is the preferred method. A simple Remove() would require a Disable/Enable pair! INPUTS iORequest - pointer to an I/O request block RESULTS error - zero if successful, else an error is returned (a sign extended copy of io_Error). SEE ALSO DoIO, SendIO, CheckIO, AbortIO exec.library/WaitPort exec.library/WaitPort NAME WaitPort -- wait for a given port to be non-empty SYNOPSIS message = WaitPort(port) D0 A0 struct Message *WaitPort(struct MsgPort *); FUNCTION This function waits for the given port to become non-empty. If necessary, the Wait() function will be called to wait for the port signal. If a message is already present at the port, this function will return immediately. The return value is always a pointer to the first message queued (but it is not removed from the queue). CAUTION More than one message may be at the port when this returns. It is proper to call the GetMsg() function in a loop until all messages have been handled, then wait for more to arrive. To wait for more than one port, combine the signal bits from each port into one call to the Wait() function, then use a GetMsg() loop to collect any and all messages. It is possible to get a signal for a port WITHOUT a message showing up. Plan for this. INPUT port - a pointer to the message port RETURN message - a pointer to the first available message SEE ALSO GetMsg SAD/--Overview-- SAD/--Overview-- Simple Amiga Debugging Kernel, known as "SAD" It is in EXEC starting in V39 -- General description -- The Simple Amiga Debugging Kernel (SAD) is a set of very simple control routines stored in the Kickstart ROM that would let debuggers control the Amiga's development enviroment from the outside. These tools would make it possible to do remote machine development/debugging via just the on-board serial port. This set of control routines is very simple and yet completely flexible, thus making it possible to control the whole machine. -- Technical Issues -- SAD will make use of the motherboard serial port that exists in all Amiga systems. The connection via the serial port lets the system be able to execute SAD without needing any of the system software up and running. (SAD will play with the serial port directly) With some minor changes to the Amiga hardware, an NMI-like line could be hooked up to a pin on the serial port. This would let external control of the machine and would let the external controller stop the machine no matter what state it is in. (NMI is that way) In order to function correctly, SAD requires the some of the EXEC CPU control functions work and that ExecBase be valid. Beyond that, SAD does not require the OS to be running. -- Command Overview -- The basic commands needed to operate SAD are as follows: Read and Write memory as byte, word, and longword. Get the register frame address (contains all registers) JSR to Address Return to system operation (return from interrupt) These basic routines will let the system do whatever is needed. Since the JSR to address and memory read/write routines can be used to download small sections of code that could be used to do more complex things, this basic command set is thus flexible enough to even replace itself. Caches will automatically be flushed as needed after each write. (A call to CacheClearU() will be made after the write and before the command done sequence) -- Technical Command Descriptions -- Since the communications with SAD is via a serial port, data formats have been defined for minimum overhead while still giving reasonable data reliability. SAD will use the serial port at default 9600 baud but the external tools can change the serial port's data rate if it wishes. It would need to make sure that it will be able to reconnect. SAD sets the baud rate to 9600 each time it is entered. However, while within SAD, a simple command to write a WORD to the SERPER register would change the baud rate. This will remain in effect until you exit and re-enter SAD or until you change the register again. (This can be usefull if you need to transfer a large amount of data) All commands have a basic format that they will follow. All commands have both an ACK and a completion message. Basic command format is: SENDER: $AF <command byte> [<data bytes as needed by command>] Receive: Command ACK: $00 <command byte> Command Done: $1F <command byte> [<data if needed>] Waiting: $53 $41 $44 $BF Waiting when called from Debug(): $53 $41 $44 $3F Waiting when in dead-end crash: $53 $41 $44 $21 The data sequence will be that SAD will emit a $BF and then wait for a command. If no command is received within <2> seconds, it will emit $BF again and loop back. (This is the "heart beat" of SAD) When called from Debug() and not the NMI hook, SAD will use $3F as the "heart beat" If SAD does not get a responce after <10> heartbeats, it will return to the system. (Execute an RTS or RTE as needed) This is to prevent a full hang. The debugger at the other end can keep SAD happy by sending a NO-OP command. All I/O in SAD times out. During the transmition of a command, if more than 2 seconds pass between bytes of data SAD will time out and return to the prompt. This is mainly to help make sure that SAD can never get into an i-loop situation. -- Data Structure Issues -- While executing in SAD, you may have full access to machine from the CPU standpoint. However, this could also be a problem. It is important to understand that when entered via NMI that many system lists may be in unstable state. (NMI can happen in the middle of the AllocMem routine or task switch, etc) Also, since you are doing debugging, it is up to you to determin what operations can be done and what can not be done. A good example is that if you want to write a WORD or LONG that the address will need to be even on 68000 processors. Also, if you read or write memory that does not exist, you may get a bus error. Following system structures may require that you check the pointers at each step. When entered via Debug(), you are now running as a "task" so you will be able to assume some things about system structures. This means that you are in supervisor state and that you can assume that the system is at least not between states. However, remember that since you are debugging the system, some bad code could cause data structures to be invalid. Again, standard debugging issues are in play. SAD just gives you the hooks to do whatever you need. Note: When SAD prompts with $BF you will be in full disable/forbid state. When $3F prompting, SAD will only do a Forbid(). It is possible for you to then disable interrupts as needed. This is done such that it is possible to "run" the system from SAD when called with Debug(). -- Data Frames and the Registers -- SAD generates a special data frame that can be used to read what registers contain and to change the contents of the registers. See the entry for GET_CONTEXT_FRAME for more details ---------------------------------------------------------------------------- - BUGS In V39 EXEC, the WRITE_BYTE command was not connected and this caused all of the command numbers to be off-by-one. For example, the READ_WORD command is listed as command $05 but in V39 is $04. However, the ACK of the commands are still correct. Also, in V39 EXEC, the READ_WORD command would return the wrong data. To determin if you are in V39 or V40 SAD, you can issue a simple SAD command at the start of the session. By sending a READ_WORD command, you may either get a READ_WORD (V40) or a READ_LONG (V39) ACK'ed back. So the data stream for a safe test would be: Send: $AF $05 $00 $F8 $00 $00 ; Read start of ROM... Recv: $00 $05 .... You have V40 SAD Recv: $00 $06 .... You have V39 SAD Note that you should be ready to read either 2 or 4 bytes of result depending on the ACK sent by the system. SAD/ALLOCATE_MEMORY SAD/ALLOCATE_MEMORY ALLOCATE MEMORY Command: $AF $0A Data: $qq $rr $ss $tt $hh $ii $jj $kk Allocate a chunk of memory that is <$qqrrsstt> bytes in size. Note that this call is only safe when SAD is in $3F prompting mode (called from Debug()) and even then may be unsafe if the system is in bad shape. (You are debugging after all) The returned address will be available to you until you release it. (It is obtained via a call to AllocVec()) The type of memory allocated is <$hhiijjkk>. Note that the allocation may fail. In that case, the address returned will be $00000000. Command ACK: $00 $0A Command DONE: $1F $0A $ww $xx $yy $zz SAD/CALL_ADDRESS SAD/CALL_ADDRESS CALL ADDRESS - JSR to the given address. Command: $AF $07 Data: $ww $xx $yy $zz Call the following address as a subroutine. No registers will be set up but the context frame will exist. Standard calling conventions apply (d0/d1/a0/a1 are available, rest must be saved) The command will be ACK'ed when received. Command ACK: $00 $07 Command DONE: $1F $07 SAD/FREE_MEMORY SAD/FREE_MEMORY FREE MEMORY Command: $AF $0B Data: $ww $xx $yy $zz Free the memory allocated with the ALLOCATE MEMORY command. This command has the same restrictions as ALLOCATE MEMORY. Memory is released by calling FreeVec() on the address <$wwxxyyzz> Command ACK: $00 $0B Command DONE: $1F $0B SAD/GET_CONTEXT_FRAME SAD/GET_CONTEXT_FRAME GET CONTEXT FRAME Command: $AF $09 Data: <none> This command will return a pointer to the saved context. This will be a pointer to all of the registers that were saved on the stack along with some other details. Returns frame address <$wwxxyyzz> The pointer returned is to the following structure: STRUCTURE SAD_FRAME,0 ; The first three are READ-ONLY... Mainly used to make it ; easier to understand what is going on in the system. ULONG SAD_VBR ; Current VBR (always 0 on 68000 CPUs) ULONG SAD_AttnFlags ; ULONG copy of the flags (UPPER WORD==0) ULONG SAD_ExecBase ; ExecBase ; These fields are the user registers... The registers are ; restored from these fields on exit from SAD... ; Note that USP is only valid if SR was *NOT* supervisor... ULONG SAD_USP ; User stack pointer ULONG SAD_D0 ; User register d0 ULONG SAD_D1 ; User register d1 ULONG SAD_D2 ; User register d2 ULONG SAD_D3 ; User register d3 ULONG SAD_D4 ; User register d4 ULONG SAD_D5 ; User register d5 ULONG SAD_D6 ; User register d6 ULONG SAD_D7 ; User register d7 ULONG SAD_A0 ; User register a0 ULONG SAD_A1 ; User register a1 ULONG SAD_A2 ; User register a2 ULONG SAD_A3 ; User register a3 ULONG SAD_A4 ; User register a4 ULONG SAD_A5 ; User register a5 ULONG SAD_A6 ; User register a6 ; This is for SAD internal use... It is the prompt that ; SAD is using... Changing this will have no effect on SAD. ULONG SAD_PROMPT ; SAD Prompt Longword... (internal use) ; From here on down is the standard exception frame ; The first two entries (SR and PC) are standard on all 680x0 CPUs UWORD SAD_SR ; Status register (part of exception frame) ULONG SAD_PC ; Return address (part of exception frame) Command ACK: $00 $09 Command DONE: $1F $09 $ww $xx $yy $zz SAD/NOP SAD/NOP NO-OP - Do nothing other than tell SAD you are still there... Command: $AF $00 Data: <none> This just tells SAD you are still there. Required so that timeouts do not exit SAD while you are not doing anything. This command will *NOT* be ACK'ed. It will just cause the timeout to be restarted. SAD/READ_ARRAY SAD/READ_ARRAY READ ARRAY - Read a range of bytes Command: $AF $0F Data: $ww $xx $yy $zz $qq $rr $ss $tt Read a range of bytes from address <$wwxxyyzz> for <$qqrrsstt> bytes Will return that number of bytes... Command will be ACK'ed when received. Command ACK: $00 $0F Command DONE: $1F $0F $uu [$uu ...] SAD/READ_BYTE SAD/READ_BYTE READ BYTE - Read a byte from the given address Command: $AF $04 Data: $ww $xx $yy $zz Read a byte from address <$wwxxyyzz> Returns <$qq> as result Command will be ACK'ed when received. Command ACK: $00 $04 Command DONE: $1F $04 $qq SAD/READ_LONG SAD/READ_LONG READ LONG - Read a long from the given address Command: $AF $06 Data: $ww $xx $yy $zz Read a long from address <$wwxxyyzz> Returns <$qqrrsstt> as result Command will be ACK'ed when received. Command ACK: $00 $06 Command DONE: $1F $06 $qq $rr $ss $tt SAD/READ_WORD SAD/READ_WORD READ WORD - Read a word from the given address (V40 SAD) Command: $AF $05 Data: $ww $xx $yy $zz Read a word from address <$wwxxyyzz> Returns <$qqrr> as result Command will be ACK'ed when received. Command ACK: $00 $05 Command DONE: $1F $05 $qq $rr BUGS This command does not return correct values in pre-V40 EXEC. SAD/RESET SAD/RESET RESET - Reset the computer... Command: $AF $10 Data: $FF $FF $FF $FF This command will reset the computer. the $FFFFFFFF value is there mainly to prevent false reset. This command will only be ACK'ed as the computer will be reset afterwards... Command will be ACK'ed when received. Command ACK: $00 $10 SAD/RETURN_TO_SYSTEM SAD/RETURN_TO_SYSTEM RETURN TO SYSTEM Command: $AF $08 Data: $00 $00 $00 $00 This command will return <exit> from SAD back to whatever started it. The 4 $00 are required as a "safty" to this command. The command will be ACK'ed only as it will have lost control of the system. Command ACK: $00 $08 SAD/TURN_OFF_SINGLE SAD/TURN_OFF_SINGLE TURN OFF SINGLE STEPPING Command: $AF $0D Data: $ww $xx $yy $zz This command will turn off SAD single stepping mode. You need to pass to it the address returned from the call to turn on single stepping mode. Command ACK: $00 $0D Command DONE: $1F $0D SAD/TURN_ON_SINGLE SAD/TURN_ON_SINGLE TURN ON SINGLE STEPPING Command: $AF $0C Data: <none> This command will turn on SAD single stepping mode. This means that SAD will single step (via 68000 trace mode) the system. SAD will take over the TRACE exception vector during this time. This command will return the contents of the vector such that you can return this value when you wish to turn off single stepping mode. Note that turning on single stepping mode while in $BF prompting will cause the step to be taken and then SAD will execute in $3F mode (non-NMI) The command returns <$wwxxyyzz> which you must use when turning off the single-step mode. Command ACK: $00 $0C Command DONE: $1F $0C $ww $xx $yy $zz SAD/WRITE_ARRAY SAD/WRITE_ARRAY WRITE ARRAY - Write a range of bytes Command: $AF $0E Data: $ww $xx $yy $zz $qq $rr $ss $tt Write a range of bytes to address <$wwxxyyzz> for <$qqrrsstt> bytes After the computer sends the ACK, you must then send the byte stream... Command will be ACK'ed when received. Command ACK: $00 $0E Command DONE: $1F $0E SAD/WRITE_BYTE SAD/WRITE_BYTE WRITE BYTE - Write the given data to the address given (V40 SAD) Command: $AF $01 Data: $ww $xx $yy $zz $qq Write the byte <$qq> to address <$wwxxyyzz> Command will be ACK'ed when received. Command ACK: $00 $01 Command DONE: $1F $01 BUGS This command does not exists in pre-V40 EXEC. This command can be emulated with the WRITE_ARRAY command with a length of 1. SAD/WRITE_LONG SAD/WRITE_LONG WRITE LONG - Write the given data to the address given Command: $AF $03 Data: $ww $xx $yy $zz $qq $rr $ss $tt Write the long <$qqrrsstt> to address <$wwxxyyzz> Command will be ACK'ed when received. Command ACK: $00 $03 Command DONE: $1F $03 SAD/WRITE_WORD SAD/WRITE_WORD WRITE WORD - Write the given data to the address given Command: $AF $02 Data: $ww $xx $yy $zz $qq $rr Write the word <$qqrr> to address <$wwxxyyzz> Command will be ACK'ed when received. Command ACK: $00 $02 Command DONE: $1F $02