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Text File | 1994-10-02 | 38.0 KB | 888 lines

=============================================================== MCOMM SUPPLEMENTAL FUNCTIONS Mike Dumdei, 6 Holly Lane, Texarkana TX 75503 =============================================================== The functions described in this document are non-async related functions provided as part of the MCOMM library. MCOMM is first and foremost a serial I/O library, therefore, much more effort went into describing the use of the async functions than you will find here. Also, because MCOMM is a serial library, most of the supplemental functions are targeted towards commun- ications programs. The video functions correctly handle all ANSI sequences commonly used by BBS systems. They also support windowed output, allowing you to limit the area of the screen that will be written to. For example, you can reserve the bottom line of the screen for a status line and no writes, ANSI clear screen commands, etc., will be allowed to overwrite or erase it. ANSI sequences supported are: CUP - cursor position HVP - horizontal, vertical position CUU - cursor up CUD - cursor down CUF - cursor forward CUB - cursor backward SCP - save cursor position RCP - restore cursor position ED - erase display EL - erase line SGR - set graphics rendition (colors) FF - form feed, not really ANSI, clears the screen Tabs, newlines, carriage returns, line feeds, backspace, the bell character, etc. are supported also. See the 'Global Video Variables' section for information on options available for handling control characters, scrolling, etc. In addition to the video routines, there are also timeout functions, crc functions, string functions, a carrier watchdog function, and several others. On the following pages, the video functions are listed first followed by the non-video type functions. Distribution policy: These functions are part of the MCOMM async library and may not be distributed without the remaining MCOMM files. No part of the registered version may be distributed or used except as stated in the license agreement. GLOBAL VIDEO VARIABLES: v_seg - segment address of video RAM, set by initvid() v_mode - current video mode, set by initvid() v_page - current video page, set by initvid() v_color - attribute to use when displaying chars, this variable is set directly by ANSI sequences that change the displayed attribute and can be set from your C program to change the current attribute (def = 7) v_snow - snow flag, if 1 chars are written to screen during vertical retrace, if 0 chars are written without waiting for retrace v_cga - a CGA video system was detected v_bios - BIOS video flag, if 1 screen writes are performed using BIOS INT 10, if 0 screen writes are done directly to video RAM v_wndsz - current window borders, set by SETWND macro (def = 0,0,24,79) v_btmrgt, v_rgt, v_btm, v_toplft, v_lft, v_top - v_wndsz individual components vs_wndsz - limits for d_msgat(), d_nchat(), & d_atrbat() vs_btmrgt, vs_toplft - vs_wndsz individual components v_scrlm - scroll mode, if 1 then the window is scrolled when the cursor would move off the bottom (def), if 0 the cursor wraps back to the top, if -1 cursor does not wrap to next line until LF displayed, if 2 cursor wraps lines without LFs but does not scroll without an LF (-1 & 2 for VT100 support) v_cntrlm - control char handling, if 1 then control chars per- form control functions, if 0 control chars are displayed as graphic characters (def = 1) v_textm - text mode, if 1 newlines are translated to CR/LF pairs, if 0 newlines are displayed as LFs (def=1) v_ansi - ansi mode, if 1 ANSI sequences are recognized, if 0 ANSI sequences are not recognized (def = 1) v_wrel - if 1 cursor location arguments for functions that are limited to the current window are relative to the top left of the current window, if 0 cursor locations are absolute (def = 0) vs_wrel - if 1 cursor location arguments for functions that are NOT limited to the current window are relative to the top left of the current window, if 0 cursor locations are absolute (def = 0) v_ansiseq - shows that an ANSI sequence is currently in process -- an ESC has been received by the display functions but the terminating alpha character has not yet been received. (EX: \33[0;36m is an ANSI sequence. 'v_ansiseq' is set to some positive value when the ESC character is received and stay positive until the sequence terminator is received. When the terminator is received, 'v_ansiseq' is set to a negative value. If the next character displayed after the terminator is not the start of another ANSI sequence, 'v_ansiseq' is reset to 0 after displaying that character. This variable is useful when stripping ANSI sequences from an incoming stream of characters or when it is necessary to interrupt an inprocess ANSI sequence. v_bksp - if 1, backspace is destructive, if 0 backspace is not destructive (def = 1) HANDLING OF UNSUPPORTED ANSI SEQUENCES: (vers 5.52 change) When an unsupported ANSI sequence is displayed, the function "x_ansi" is called. A default version of "x_ansi" that displays the unrecognized sequence is included in the libraries. To override the default handler with one of your own, simply put an "x_ansi" function in your code. Your function will be passed a pointer to any unrecognized ANSI sequences. The function prototype has the following form: void x_ansi(char *ansi_str); See TXZM.C for an example of function that overrides the default "x_ansi" handler. INTERRUPTING INPROCESS ANSI SEQUENCES: This section suggests some possible methods for handling the situation where an ANSI sequence is in progress and it is nec- essary to display characters that are not part of the sequence and then resume the sequence. An example of where this situa- tion is a terminal program that is displaying incoming data containing ANSI codes and the user of the program presses a key that requires screen output in the middle of one of those codes: Incoming data: ESC[0; (beginning of ANSI code) User keypress: F1 (user wants a help screen) More incoming: 36m (completion of ANSI code) The ANSI handler in the video library sees this: ESC[0;+----------------+ | Help Screen | +----------------+36m and since it doesn't know what to to with an ANSI code that looks like that you see a small back arrow (for unrecognized ANSI code), the help screen, and a 36m. To avoid this problem, you can do one of three things. The first is you can ignore the local user input until the inprocess ANSI sequence is completed. The v_ansiseq variable described previously can be used to test whether or not an ANSI sequence is currently in process. Example: if (KBHIT()) { while (v_ansiseq && ((ch = rx_timeout(1)) != TIMED_OUT)) d_ch(ch); proc_keypress(); } The second method is to use the 'd_msgat' function to display local strings. It automatically save the ANSI sequence status, and the present cursor position before displaying the passed string. On exit, the current status of any inprocess ANSI sequences and the cursor position are restored. It will also place strings outside the current window making it the best function for updating the terminal status line and displaying local screens and messages. The last option is to manually preserve the v_ansiseq variable, display local messages, and then manually restore v_ansiseq: temp = v_ansiseq, v_ansiseq = 0; displayhelp(); v_ansiseq = temp; VIDEO MACROS: --------------------------------------------------------------- SETWND(top, left, btm, rgt) -- Set Window Dimensions --------------------------------------------------------------- This macro is used to set the global variable that defines the screen area that will be affected by the majority of the video functions. Initially set to 0,0,24,79. --------------------------------------------------------------- SETTOPLFT(top, lft), SETBTMRGT(btm, rgt) --------------------------------------------------------------- Same as above but only sets one corner. --------------------------------------------------------------- SETsWND(top, left, btm, rgt) -- Set Screen Dimensions --------------------------------------------------------------- Sets the screen limits for the functions that are allowed to write outside the current window. --------------------------------------------------------------- SETsTOPLFT(top, lft), SETsBTMRGT(btm, rgt) --------------------------------------------------------------- Same as SETsWND but for one corner only. --------------------------------------------------------------- SCRBUF(rows, cols) --------------------------------------------------------------- Returns a value that is the required buffer size for the pu_scrnd and fpu_scrnd functions. It is used like this: sbuf = malloc(SCRBUF(25,80)); if (sbuf != NULL) pu_scrnd(0, 0, 25, 80); --------------------------------------------------------------- d_strnat(row,col,char,attrib,count) --------------------------------------------------------------- Macro for compatibility with older versions of ANSIDRV. VIDEO FUNCTIONS: --------------------------------------------------------------- initvid -- Initializes Video Variables --------------------------------------------------------------- int initvid(void); Initializes the global video variables, v_seg, v_mode, v_page, and v_snow. You MUST call this function before using any of the other video functions. Calling 'initvid' does not automatically cause the linker to pull in the code for the remaining ANSI video routines. Initvid only includes the global variables and enough code to initialize those variables. --------------------------------------------------------------- loc -- Locate the Cursor --------------------------------------------------------------- void loc(int row, int col); Locates the cursor at row, col. The top left of the screen is 0,0. If an attempt is made to locate the cursor outside the current window the cursor is placed on the window edge closest to the passed location. Setting the global variable 'v_wrel' to a non-zero value will make location 0,0 be the top, left corner of the current window. --------------------------------------------------------------- d_strat -- Display String At Specified Location --------------------------------------------------------------- void d_strat(int row, int col, char *string); This function displays a string at row, col. The attribute used is the current value of the global variable 'v_color'. The area where the string can be displayed is limited to the current window (set by SETWND). --------------------------------------------------------------- d_str -- Display String At Current Location --------------------------------------------------------------- void d_str(char *string); Displays a string at the current cursor position using v_color for the attribute. --------------------------------------------------------------- d_chat -- Display Char At Specified Location --------------------------------------------------------------- void d_chat(int row, int col, char ch); Displays one character at the specified position using v_color for the attribute. --------------------------------------------------------------- d_ch -- Display Char at Current Location --------------------------------------------------------------- void d_ch(char ch); Display one character at the present cursor position using v_color for the attribute. --------------------------------------------------------------- d_msgat -- Display Message At Location --------------------------------------------------------------- void d_msgat(int row, int col, int atrib, char *str); Displays string at the specified location using the specified attribute. This routine is not limited to writing within the current window. It is limited by the variable set by the SETsWND macro (s stands for screen). The routine does not move the cursor and does not break up in process ANSI sequences. Used to display strings outside the current window. --------------------------------------------------------------- d_msgatd -- Display Message At Location Direct Write --------------------------------------------------------------- void d_msgatd(int row, int col, int atrib, char *str); This routine writes 'str' at the specified location using the given attribute. Unlike the previous function, this function does not support ANSI or control characters. It is for displaying strings on the screen in the fastest possible manner. The 'v_bios' variable described in the list of global variables does not apply to this function. It always uses direct screen writes. --------------------------------------------------------------- d_atrbat -- Display Attribute At Location With Count --------------------------------------------------------------- void d_atrbat(int row, int col, int atrb, int count); Resets the displayed attribute at the specified location to the given attribute for the given number of locations. This rout- ine performs like d_msgat() in regard to window limitations, cursor movement, and ANSI sequences. --------------------------------------------------------------- d_nchat -- Display Char At Location With Count --------------------------------------------------------------- void d_nchat(char row, char col, char ch, char atrb, int nbr, char dir); Displays 'ch', 'nbr' times, using 'atrb' for the attribute, at 'row, col'. If 'dir' is 0 the chars are displayed vertically otherwise they are displayed horizontally. This routine performs like d_msgat in regard to window limitations, cursor movement, and ANSI sequences. --------------------------------------------------------------- pu_scrnd -- Move Specified Screen Region To A Buffer --------------------------------------------------------------- void pu_scrnd(int row, int col, int nrows, int ncols, char *buf); This function saves a section of the video display beginning at 'row', 'col', that is 'nrows' high and 'ncols' wide. It also saves the current cursor position and shape. The buffer to hold the screen information must be (2 * nrows * ncols) + 16 bytes in size. The 'v_bios' variable does not apply to this function. It operates in direct write mode only. --------------------------------------------------------------- po_scrnd -- Restore a Screen Saved by 'pu_scrnd' Function --------------------------------------------------------------- void po_scrnd(char *buf); Restores the screen and cursor information that was placed in 'buf' by a previous pu_scrnd call. The 'v_bios' function does not apply to this function. --------------------------------------------------------------- fpu_scrnd -- Move Specified Screen Region To A FAR Buffer --------------------------------------------------------------- void fpu_scrnd(int row, int col, int nrows, int ncols, char _far *buf); Same as pu_scrnd except moves screen information to a FAR buffer. --------------------------------------------------------------- fpo_scrnd -- Restore a Screen Saved by 'fpu_scrnd' Function --------------------------------------------------------------- void fpo_scrnd(char _far *buf); Same as po_scrnd except restores data pushed by 'fpo_scrnd'. --------------------------------------------------------------- pushscrn -- Move Specified Screen Region To A Buffer ( C ) --------------------------------------------------------------- int pushscrn(int row, int col, int nrows, int ncols); C function that utilizes pu_scrnd and malloc to build a last in first out stack of up to 10 screens. Performs the same as pu_scrnd except automatically allocates the buffer space. C source code is included for this function. Returns 0 if successful, non-zero if an attempt is made to push too many screens or the call to malloc space for the screen data fails. --------------------------------------------------------------- popscrn -- Restore Last Screen Saved by 'pushscrn' ( C ) --------------------------------------------------------------- int popscrn(void); Restores last screen pushed by pushscrn function. Returns 0 if successful or non-zero if an attempt is made to pop a screen when no more screens remain in the screen stack. --------------------------------------------------------------- fpushscrn -- Move Specified Screen Region To FAR Buffer ( C ) --------------------------------------------------------------- int fpushscrn(int row, int col, int nrows, int ncols); Same as pushscrn except the screen buffers are allocated from far memory using your compiler's version of a far malloc function. (MSC _fmalloc, Turbo C = farmalloc). Source code is included if you are using a compiler that has a different name for the function to do this. --------------------------------------------------------------- fpopscrn -- Restore Last Screen Saved by 'fpushscrn' ( C ) --------------------------------------------------------------- int fpopscrn(void); Same as popscrn except restores last screen pushed by fpushscrn. --------------------------------------------------------------- moveblk -- Move Screen To Buffer / Buffer To Screen --------------------------------------------------------------- void moveblk(int row, int col, int nrows, int ncols, char *buf, int dirflag); This function does the same thing as pu_scrnd and po_scrnd combined except it does not save data on the cursor position or shape and all args are needed when both saving and restoring. The 'dirflag' determines which direction the data is to be moved. If it is NZ, data is transferred from the screen to the buffer. If it is zero, then buffer data is transferred to the screen. The additional 16 bytes of buffer space required by pu_scrnd are not required for this function since it does not build the header for the screen region and cursor data. --------------------------------------------------------------- rd_scrn -- Read Attrib/Char At Cursor Position --------------------------------------------------------------- int rd_scrn(void); Reads the attribute and character at the current cursor pos- ition. The attribute is returned in the upper 8 bits of the return value and the character in the lower 8 bits. --------------------------------------------------------------- rd_scrnd -- Read Screen String From Specified Location --------------------------------------------------------------- char *rd_scrnd(int row, int col, int nbytes, char *buf); Reads a string that is a maximum of 'nbytes' long beginning at the specified location. The string is stored in 'buf' and trailing spaces are trimmed. The 'v_bios' variable does not apply to this function. The return value is a pointer to 'buf'. --------------------------------------------------------------- cls -- Clear Currently Defined Window --------------------------------------------------------------- void cls(void); Clears the current window using v_color for the attribute. Re- turns nothing. --------------------------------------------------------------- scrlup -- Scroll Window Up --------------------------------------------------------------- void scrlup(int nbrlines); Scrolls the current window up the specified number of lines. The attribute used for blank lines is 'v_color'. --------------------------------------------------------------- scrldn -- Scroll Window Down --------------------------------------------------------------- void scrldn(int nbrlines); Same as previous function except scrolls down. --------------------------------------------------------------- scrlupat -- Scroll Specified Area Up --------------------------------------------------------------- void scrlup(int top, int lft, int btm, int rgt, int nlines); Same as previous scrlup function except instead of using the current window, it scrolls the specified area. --------------------------------------------------------------- scrldnat -- Scroll Specified Area Down --------------------------------------------------------------- void scrldn(int nbrlines); Same as previous scrldn function except instead of using the current window, it scrolls the specified area. --------------------------------------------------------------- setcurloc -- Set Cursor Location --------------------------------------------------------------- void setcurloc(int location); Similar to loc(), but this function passes the row and column one variable with the upper 8 bits being the row and the lower 8 bits the column. This function is used in conjunction with getcurloc() to save and restore the cursor position. --------------------------------------------------------------- getcurloc -- Get Cursor Location --------------------------------------------------------------- int getcurloc(void); Returns the cursor location as an integer. The upper 8 bits is the row, and the lower 8 bits is the column. --------------------------------------------------------------- setcursiz -- Set Cursor Size --------------------------------------------------------------- void setcursiz(int); Sets the starting and ending scan lines for the cursor. The upper 8 bits are the starting scan line and the lower 8 bits are the ending scan line. --------------------------------------------------------------- getcursiz -- Get Cursor Size --------------------------------------------------------------- int getcursiz(void); Returns the current starting and ending scan lines of the cur- sor. The high bits are the starting scan line and the lower 8 bits are the ending scan line. --------------------------------------------------------------- setvmode -- Set Video Mode --------------------------------------------------------------- void setvmode(int mode); Sets the video mode to 'mode'. The only modes that these func- tions will work in, however, are the 80 x 25 text modes. --------------------------------------------------------------- getvmode -- Get Video Mode --------------------------------------------------------------- int getvmode(void); Returns the current video mode. --------------------------------------------------------------- setvpage -- Set Video Page --------------------------------------------------------------- void setvpage(int page); Sets the video page to 'page'. Pages are only supported on color systems. This function also modifies v_seg so that it reflects the new page value set. --------------------------------------------------------------- getvpage -- Get Video Page --------------------------------------------------------------- int getvpage(void); Returns the current video page. --------------------------------------------------------------- setvbordr -- Set Video Border --------------------------------------------------------------- void setvbordr(int attrib); Sets the border color of the screen. MISCELLANEOUS FUNCTIONS: --------------------------------------------------------------- str*just -- right, left, or center justify a string. --------------------------------------------------------------- These functions 1st trim all spaces (ASCII 32's) and then just- ify the string in the specified field width using the specified pad character. The memory area where the string is located must be at least field size + 1 in size. If the string is longer than the field width, strljust and strcentr truncate the right portion of the string; strrjust will cut off the right side. Only ASCII 32's are trimmed. Returns a pointer to the justified string. char *strrjust(char *, int, char); char *strljust(char *, int, char); char *strcentr(char *, int, char); str_out = strrjust(str_in, fieldsz, padchar); --------------------------------------------------------------- str*trim -- trims spaces (ASCII 32's only) from a string. --------------------------------------------------------------- Trims spaces from left, right, or both ends of a string. Returns pointer to the passed string. char *strrtrim(char *); char *strltrim(char *); char *strtrim(char *); str_out = strrtrim(str_in); --------------------------------------------------------------- strsum -- strcat for multiple strings. --------------------------------------------------------------- Makes one string from multiple strings. Unlike strcat, the first string in the list is not one of the strings to add but instead is a buffer for the result of adding the rest of the strings in the list. The args to the function are: the dest, a variable number of char *'s, a NULL ptr Returns a pointer to the result string. char *strsum(char *, ...); str_out = strsum(str_out, str_in1, str_in2, ..., NULL); --------------------------------------------------------------- strpbrkf -- finds 1st char in str1 not in str2. --------------------------------------------------------------- This function looks for the first character in 'str1' that does not belong to the character set contained in 'str2' and returns a pointer to that character. If 'str1' consists entirely of characters in 'str2', NULL is returned. Opposite of strpbrk. char *strpbrkf(char *, char *); rtnstr = strpbrkf(str1, str2); --------------------------------------------------------------- strrstr -- find last occurrence of str2 in str1. --------------------------------------------------------------- This function returns a pointer to the last occurrence of 'str2' within 'str1'. If 'str2' is not in 'str1', NULL is returned. This is identical to the standard 'strstr' function except it works from the end of 'str1' towards the beginning instead of the other way. char *strrstr(char *, char *); rtnstr = strrstr(str1, str2); --------------------------------------------------------------- strcntch -- returns number occurrences of char in string. --------------------------------------------------------------- int strcntchr(char *, char); count = strcntchr(string, srchchar); --------------------------------------------------------------- calc_crc -- 16 bit CRC routine for block data. --------------------------------------------------------------- Calculates the CRC for a block of data 'count' bytes long. Returns CRC. int calc_crc(char *, int); crc = calc_crc(data, nbr_bytes_of_data); --------------------------------------------------------------- update_crc -- 16 bit CRC for character at a time data. --------------------------------------------------------------- Returns updated CRC. int update_crc(int, char); crc = update_crc(crc, char); --------------------------------------------------------------- watchdogset -- Enables/Disables watchdog function (C function) watchdoghook -- ASM function used by WATCHDOG.C --------------------------------------------------------------- int watchdogset(int flag, int combase) To enable: call with flag = 1 combase = base adrs of comm chip (ex: 3F8) To disable: call with flag = 0 combase = don't care This function monitors Carrier Detect on the selected serial port and does a cold reboot if the carrier is lost. If you use both this function and the TIMEOUT functions make sure you uninstall the hooks in the reverse order that you installed them and make sure that you uninstall them before you exit your program. Failing to do this will cause your system to crash (the redirected interrupt vectors are now pointing to freed memory instead of a program). --------------------------------------------------------------- ctshookset -- Patch to BIOS INT14 to prevent timeouts when using CTS handshaking (C function) int14ctshook -- ASM function used with CTSHOOKSET --------------------------------------------------------------- int ctshookset(int flag, int portval, int combase) void interrupt far int14ctshook(void); To enable: call with flag = 1 portval = COM1 (0) or COM2 (1) combase = base adrs of comm chip (ex: 3F8) To disable: call with flag = 0 portval = don't care combase = don't care This function sets a hook into the BIOS serial interrupt vector that waits indefinitely for CTS to go high on the specified port when sending data. All INT14 calls that are not for the specified port and all service requests except for 'send byte' are passed on to the old INT14 vector unaltered. In other words for the hook to have any effect when INT14 is called: 1) DX has to equal the 'portval' you set here 2) AH has to equal '1' -- the send char service ID The effect it has then is to wait for CTS to be true then exe- cute the old INT14 interrupt. The purpose of the function is keep high speed modems that CTS handshake from creating timeout errors when redirecting stdout and stderr to the comm port. Be SURE to uninstall the hook before exiting your program or the redirected interrupt vector will be pointing to free memory instead of an interrupt handler. --------------------------------------------------------------- tickhookset -- Enables/Disables 'ticker' for timer functions --------------------------------------------------------------- int tickhookset(int flag) To enable: call with flag = 1 To disable: call with flag = 0 This function enables the 'tick counter' used by the timeout and tdelay functions by pointing the TIMER interrupt vector, 1Ch, to a new interrupt handler that increments the counter approximately 18.2 times per second. The advantage of using this method over the BIOS function is no coding is needed to account for the possibility of calling your timer functions near midnight. The 'tick counter' is a long and may be read by calling 'get_ticker'. YOU MUST DISABLE 'TICKER' BEFORE EXITING YOUR PROGRAM. --------------------------------------------------------------- set_timeout -- initializes a timer set_longtimeout -- initialize a long timer timed_out -- checks if a timeout has occurred --------------------------------------------------------------- void set_timeout(long *t_out, unsigned ticks); int timed_out(long *t_out); These functions work in conjunction with each other and require the 'tick counter' to be activated by TICKHOOKSET. The fol- lowing macros are defined in EXTRA.H: SET_TO_TENTHS(to, tenths) set_timeout((&to), (tenths)*9/5) SET_TO_SECS(to, secs) set_timeout((&to), (secs)*18) SET_TO_MINS(to, mins) set_timeout((&to), (mins)*1080) After setting the timeout value with one of the above macros you then call timed_out() see if a timeout has occurred. Here is an example: long to; int toolong = 0; tickhookset(1); /* enable hook */ SET_TO_SECS(to, 2); /* set timeout for 2 secs */ while (!(toolong = timed_out(&to))) { if (condition_met()) /* wait for cond 2 secs max */ break; } if (toolong) /* timed out if toolong NZ */ return TIMEOUT_ERR; Notice that the macro does not require the '&' operator but the call to timed_out() does. Using these functions, you may have as many timeouts going as you have timeout variables. --------------------------------------------------------------- get_ticker -- get the current value of internal tick counter --------------------------------------------------------------- long get_ticker(void); Returns the value of the internal tick counter. This counter is incremented 18.2 times a second from the time tickhookset(1) is called until tickhookset(0) is called. --------------------------------------------------------------- tdelay -- kill time function --------------------------------------------------------------- int tdelay(unsigned ticks); This functions delays the specified number of ticks and then returns. Before using this function you must enable the internal tick counter by calling 'tickhookset'. The following macros are defined in EXTRA.H: DELAY_TENTHS(tenths) tdelay(((tenths)*9/5)+1) DELAY_SECS(secs) tdelay((secs)*18) DELAY_MINS(mins) tdelay((mins)*1080)