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Text File | 2006-10-19 | 12.1 KB | 546 lines

************************************************************ * * * MKFDR * * * * This procedure will take in file information and * * create an FDR on disk and insert it into the parent * * directory. If the file exists, its flags are checked * * for compatibility. * * * * Inputs: * * MKFL3 - # of level 3 records in the file * * MKFRL - Record length * * MKFRPS - # of records per sector * * MKFEOF - End of File offset * * MKFLAG - File flags * * MKFSZ - Size of file in sectors * * ! * * Output: * * R1 = status (0=success) * * * ************************************************************ ************************************************************ * * * Revision history - * * * * 10-19-95 - I am completely rewriting this routine * * because I didn't like how the old routine would have * * to scan the directory twice if a file didn't exist. * * I no longer call GETFDR in this routine. * * * ************************************************************ MKFDR * OK - first we will see if the file exists or not. * LDCR @B02,4 Save return address MOV R11,@MKSR11 * See if the parent directory exists * BL @GETDDR CI R5,0 JNE MKF1 LI R1,7 File Error B @MKFRT MKF1 LDCR @B03,4 MOVB @22(R5),R1 Get # of files in directory * Lets read the FDIR * MOV @24(R5),R7 MOV R6,R3 SRL R3,8 SLA R3,1 LDCR @B02,4 MOV R7,@SFDRAU Save AU of FDIR LDCR @B04,4 MPY @SAUTBL(R3),R7 LI R2,SECBUF SRL R8,1 JNC MKF3 AI R2,>100 MKF3 SRL R7,1 JNC MKF4 AI R8,>8000 MKF4 LDCR @ZERO,4 BLWP @BANKIT DATA SCSIRD JNE MKFERR * Move the FDIR to another buffer * LI R4,DFDR LI R0,256 MKF5 MOV *R2+,R3 LDCR @B02,4 MOV R3,*R4+ LDCR @ZERO,4 DECT R0 JNE MKF5 * Copy the filename to FDIR * LI R2,NCB+39 LI R3,FNCB LDCR @B02,4 MKF6 CB *R2,@PERIOD JEQ MKF7 DEC R2 CI R2,NCB-1 JNE MKF6 MKF7 INC R2 MKF7A MOVB *R2+,R4 LDCR @ZERO,4 MOVB R4,*R3+ LDCR @B02,4 CB *R2,@SPACE JEQ MKF8 CI R2,NCB+40 JNE MKF7A MKF8 LDCR @ZERO,4 MKF8A CI R3,FNCB+10 JEQ MKF9 MOVB @SPACE,*R3+ JMP MKF8A MKF9 * Now set the bounds of our search. If the directory is * empty, we can skip this part * CLR R0 SRL R1,8 CI R1,0 JEQ MKF17 DEC R1 MKF10 MOV R0,R10 Compute the midpoint A R1,R10 ANDI R10,>FFFE LDCR @B02,4 MOV @DFDR(R10),R7 MOV R6,R3 SRL R3,8 SLA R3,1 LDCR @B04,4 MPY @SAUTBL(R3),R7 LI R2,SECBUF SRL R8,1 JNC MKF11 AI R2,>100 MKF11 SRL R7,1 JNC MKF12 AI R8,>8000 MKF12 LDCR @ZERO,4 BLWP @BANKIT DATA SCSIRD JNE MKFERR * OK, We got the FDR in the buffer. Compare file names * LI R3,FNCB LI R9,10 MKF13 C *R2+,*R3+ JL MKF14 JH MKF15 DECT R9 JNE MKF13 * The file exists! Branch to a part of code that checks * the file type and protection. LDCR @B02,4 * MOV @DFDR(R10),R10 Save AU of FDR MOV @DFDR(R10),@MKFAU1 B @MKF30 MKF14 C R0,R1 JEQ MKF16 SRL R10,1 MOV R10,R0 INC R0 JMP MKF10 MKF15 C R0,R1 JEQ MKF17 SRL R10,1 MOV R10,R1 C R0,R1 JEQ MKF17 DEC R1 JMP MKF10 MKFERR LI R1,6 Device Error MKFRT LDCR @B02,4 MOV @MKSR11,R11 RT MKF16 INC R0 MKF17 SLA R0,1 AI R0,DFDR * Lets make sure we don't already have 127 files in * this directory before trying to create a new one LDCR @B03,4 CB @B127,@22(R5) JNE MKF17A MKF18 LI R1,4 Out of space error JMP MKFRT MKF17A * Let's allocate an AU to store the file's FDR and insert * it into the parent's FDIR * CLR R3 Start at beginning CLR R7 No preferred AU LI R8,1 We want 1 AU LDCR R3,0 Select RAM bank 0 * LDCR @ZERO,4 BLWP @ALLOC JNE MKFERR CI R4,0 JEQ MKF18 Out of space error * Now insert the AU into the FDIR * LDCR @B02,4 LI R1,DFDR+252 MKF19 C R1,R0 JEQ MKF20 MOV @-2(R1),*R1 DECT R1 JMP MKF19 MKF20 MOV R5,*R0 MOV R5,@MKFAU1 Save AU of FDR * Now write the FDIR back out to disk. * MOV @SFDRAU,R7 LDCR @B04,4 MOV R6,R3 SRL R3,8 SLA R3,1 MPY @SAUTBL(R3),R7 LI R2,SECBUF SRL R8,1 JNC MKF21 AI R2,>100 MKF21 SRL R7,1 JNC MKF22 AI R8,>8000 MKF22 LDCR @ZERO,4 BLWP @BANKIT DATA SCSIRD JNE MKFERR LI R3,DFDR LI R0,256 MKF23 LDCR @B02,4 MOV *R3+,R4 LDCR @ZERO,4 MOV R4,*R2+ DECT R0 JNE MKF23 BLWP @BANKIT DATA SCSIWT JNE MKFERR * Now that we have the new FDIR written to disk, increment * the file counter in the parent DDR * BL @GETDDR LDCR @B03,4 AB @B01,@22(R5) Increment cache LDCR @B04,4 MOV @SAVEAU,R7 MOV R6,R3 SRL R3,8 SLA R3,1 MPY @SAUTBL(R3),R7 LI R2,SECBUF SRL R8,1 JNC MKF24 AI R2,>100 MKF24 SRL R7,1 JNC MKF25 AI R8,>8000 MKF25 LDCR @ZERO,4 BLWP @BANKIT DATA SCSIRD JNE MKFERR * now increment the file counter AB @B01,@22(R2) * And write back out to disk MKF25C BLWP @BANKIT DATA SCSIWT JNE MKFERR * If this was the VIB, we must also write it out * in the copy CI R8,0 JNE MKF25B CI R7,0 JNE MKF25B AI R8,16 JMP MKF25C MKF25B * Now we will create an FDR in the DFDR buffer in bank 2 * Start by filling in the file name LI R1,DFDR LI R2,FNCB LI R0,10 MKF25A LDCR @ZERO,4 MOV *R2+,R3 LDCR @B02,4 MOV R3,*R1+ DECT R0 JNE MKF25A CLR *R1+ Extended record length MOVB @MKFLAG,*R1+ File flags MOVB @MKFRPS,*R1+ Records per sector CLR *R1+ # of sectors allocated MOVB @MKFEOF,*R1+ End of file offset MOVB @MKFRL,*R1+ Record Length MOV @MKFL3,*R1+ # of level 3 records CLR *R1+ Creation date CLR *R1+ CLR *R1+ Update date CLR *R1+ LI R0,'FI' MOV R0,*R1+ CLR *R1+ Parent FDR CLR *R1+ Offspring AU CLR *R1+ AU's allocated for FDR MOV @SFDRAU,*R1+ Pointer to FDIR CLR *R1+ Extended information MKF26 CLR *R1+ Data chain pointers CI R1,DFDR+256 JNE MKF26 * Now branch to a section of code that will allocate * all the AU's we need for the file B @MKF40 ************************************************************ * * * The file already exists, so we have to check to make * * sure the file attribute match. If they do, we will * * make sure we have enough AUs allocated and rewrite * * the FDR back to disk. * * * ************************************************************ MKF30 * Start by copying the FDR to the DFDR buffer in bank 2 LI R1,DFDR AI R2,-10 It still points to FDR LI R0,256 MKF31 LDCR @ZERO,4 MOV *R2+,R3 LDCR @B02,4 MOV R3,*R1+ DECT R0 JNE MKF31 * Check to see if the old file was protected * MOVB @DFDR+12,R1 Get file flags COC @PROBIT,R1 JNE MKF32 LI R1,1 File protect error B @MKFRT MKF32 * If it is a program file, that is all we have to check. * Otherwise we must check DISPLAY/INTERNAL, FIXED/VARIABLE * and record length ANDI R1,>8000 JNE MKF34A * It's not a program file. Make sure attributes match * MOVB @DFDR+12,R1 ANDI R1,>C100 MOVB @MKFLAG,R2 ANDI R2,>C100 C R1,R2 JEQ MKF34 MKF33 LI R1,7 File error B @MKFRT MKF34 * Now check record length CB @DFDR+17,@MKFRL JNE MKF33 * Everything checks out. Lets rewrite a couple fields and * allocate some AUs! MKF34A MOVB @MKFLAG,@DFDR+12 File flags MOVB @MKFEOF,@DFDR+16 End Of File offset MOV @MKFL3,@DFDR+18 # of level 3 records ** * * Here we will allocate AU's if we need to * ** MKF40 MOV @MKFSZ,R1 Get # of sectors wanted LDCR @B04,4 MOV R6,R3 SRL R3,8 SLA R3,1 MOV @SAUTBL(R3),R3 A R3,R1 DEC R1 CLR R0 DIV R3,R0 MOV R0,R8 R8 has # of AU's needed LDCR @B02,4 C R8,@DFDR+34 See if we need any more JL MKF44 JEQ MKF44 * Ok - We need to allocate more AU's for this FDR! * S @DFDR+34,R8 MKF40A LI R3,256*8 AU Boundry CLR R7 No preferred starting AU LDCR @ZERO,4 BLWP @ALLOC * JNE MKFERR CI R4,0 JNE MKF41 LI R1,4 Out Of Space Error B @MKFRT MKF41 * Fill in the next cluster of the FDR LI R3,DFDR+40 LDCR @B02,4 MKF42 C *R3,@ZERO JEQ MKF43 AI R3,4 JMP MKF42 MKF43 MOV R5,*R3+ MOV R5,*R3 A R4,*R3 DEC *R3 A R4,@DFDR+34 Add to # of AUs allocated S R4,R8 See if we need to get any more JNE MKF40A MKF44 * Now lets fill in the # of sectors currently allocated. * For program files, this will be whatever the user wanted. * For data files, it is equal to the number of AU's * allocated time the number of sectors per AU. * MOVB @DFDR+12,R1 Get file flags ANDI R1,>0100 JNE MKF45 MOV @DFDR+34,R1 MOV R6,R3 SRL R3,8 SLA R3,1 LDCR @B04,4 MPY @SAUTBL(R3),R1 LDCR @B02,4 MOV R2,@DFDR+14 JMP MKF46 MKF45 MOV @MKFSZ,@DFDR+14 MKF46 * All we have to do now is write the FDR back out to * disk and we're done! LDCR @B02,4 MOV @MKFAU1,R7 Restore AU of FDR MOV R6,R3 SRL R3,8 SLA R3,1 LDCR @B04,4 MPY @SAUTBL(R3),R7 LI R2,SECBUF SRL R8,1 JNC MKF47 AI R2,>100 MKF47 SRL R7,1 JNC MKF48 AI R8,>8000 MKF48 LDCR @ZERO,4 BLWP @BANKIT DATA SCSIRD Read old block * JNE MKFERR LI R1,DFDR LI R0,256 MKF49 LDCR @B02,4 MOV *R1+,R4 LDCR @ZERO,4 MOV R4,*R2+ DECT R0 JNE MKF49 BLWP @BANKIT Write it back out DATA SCSIWT * JNE MKFERR CLR R1 Success! B @MKFRT