| 53,7 → 53,7 |
|---|
| |
| #include <process.h> |
| |
| #include "rmod.h" |
| #include "rmodinit.h" |
| |
| struct config { |
| int locate; |
| 62,130 → 62,6 |
|---|
| } cfg; |
| |
| |
| #define RMOD_OFFSET_ENVSEG 0x08 |
| #define RMOD_OFFSET_INPBUFF 0x0A |
| #define RMOD_OFFSET_ROUTINE 0x8C |
| |
| /* returns segment where rmod is installed */ |
| unsigned short rmod_install(unsigned short envsize) { |
| char far *myptr, far *mcb; |
| unsigned short far *owner; |
| unsigned int rmodseg = 0xffff; |
| unsigned int envseg = 0; |
| |
| /* read my current env segment from PSP */ |
| _asm { |
| push ax |
| push bx |
| mov bx, 0x2c |
| mov ax, [bx] |
| mov envseg, ax |
| pop bx |
| pop ax |
| } |
| |
| printf("original (PSP) env buffer at %04X\r\n", envseg); |
| /* if custom envsize requested, convert it to number of paragraphs */ |
| if (envsize != 0) { |
| envsize += 15; |
| envsize /= 16; |
| } |
| |
| |
| _asm { |
| /* link in the UMB memory chain for enabling high-memory allocation (and save initial status on stack) */ |
| mov ax, 0x5802 /* GET UMB LINK STATE */ |
| int 0x21 |
| xor ah, ah |
| push ax /* save link state on stack */ |
| mov ax, 0x5803 /* SET UMB LINK STATE */ |
| mov bx, 1 |
| int 0x21 |
| /* get current allocation strategy and save it in DX */ |
| mov ax, 0x5800 |
| int 0x21 |
| push ax |
| pop dx |
| /* set strategy to 'last fit, try high then low memory' */ |
| mov ax, 0x5801 |
| mov bx, 0x0082 |
| int 0x21 |
| /* ask for a memory block and save the given segment to rmodseg */ |
| mov ah, 0x48 |
| mov bx, (rmod_len + 15) / 16 |
| int 0x21 |
| jc ALLOC_FAIL |
| mov rmodseg, ax |
| /* ask for a memory block for the environment and save it to envseg (only if custom size requested) */ |
| mov bx, envsize |
| test bx, bx |
| jz ALLOC_FAIL |
| mov ah, 0x48 |
| int 0x21 |
| jc ALLOC_FAIL |
| mov envseg, ax |
| |
| ALLOC_FAIL: |
| /* restore initial allocation strategy */ |
| mov ax, 0x5801 |
| mov bx, dx |
| int 0x21 |
| /* restore initial UMB memory link state */ |
| mov ax, 0x5803 |
| pop bx /* pop initial UMB link state from stack */ |
| int 0x21 |
| } |
| |
| if (rmodseg == 0xffff) { |
| puts("malloc error"); |
| return(0xffff); |
| } |
| |
| /* copy rmod to its destination */ |
| myptr = MK_FP(rmodseg, 0); |
| _fmemcpy(myptr, rmod, rmod_len); |
| |
| /* mark rmod memory as "self owned" */ |
| mcb = MK_FP(rmodseg - 1, 0); |
| owner = (void far *)(mcb + 1); |
| *owner = rmodseg; |
| _fmemcpy(mcb + 8, "SVARCOM", 8); |
| |
| /* mark env memory as "self owned" (only if allocated by me) */ |
| if (envsize != 0) { |
| printf("envseg allocated at %04X:0000 with %u paragraphs\r\n", envseg, envsize); |
| mcb = MK_FP(envseg - 1, 0); |
| owner = (void far *)(mcb + 1); |
| *owner = rmodseg; |
| _fmemcpy(mcb + 8, "SVARENV", 8); |
| } |
| |
| /* write env segment to rmod buffer */ |
| owner = MK_FP(rmodseg, RMOD_OFFSET_ENVSEG); |
| *owner = envseg; |
| |
| /* |
| printf("MCB sig: %c\r\nMCB owner: 0x%04X\r\n", mcb[0], *owner); |
| { |
| int i; |
| for (i = 0; i < 17; i++) { |
| printf("%02x ", mcb[i]); |
| } |
| printf("\r\n"); |
| for (i = 0; i < 17; i++) { |
| if (mcb[i] > ' ') { |
| printf(" %c ", mcb[i]); |
| } else { |
| printf(" . ", mcb[i]); |
| } |
| } |
| printf("\r\n"); |
| }*/ |
| |
| return(rmodseg); |
| } |
| |
| |
| /* returns zero if s1 starts with s2 */ |
| static int strstartswith(const char *s1, const char *s2) { |
| while (*s2 != 0) { |
| 213,24 → 89,6 |
|---|
| } |
| |
| |
| /* scan memory for my shared buffer, return segment of buffer */ |
| static unsigned short rmod_find(void) { |
| unsigned short i; |
| unsigned short far *pattern; |
| |
| /* iterate over all paragraphs, looking for my signature */ |
| for (i = 0; i != 65535; i++) { |
| pattern = MK_FP(i, 0); |
| if (pattern[0] != 0x1983) continue; |
| if (pattern[1] != 0x1985) continue; |
| if (pattern[2] != 0x2017) continue; |
| if (pattern[3] != 0x2019) continue; |
| return(i); |
| } |
| return(0xffff); |
| } |
| |
| |
| static int explode_progparams(char *s, char const **argvlist) { |
| int si = 0, argc = 0; |
| for (;;) { |
| 302,15 → 160,6 |
|---|
| printf("rmod_inpbuff at %04X:%04X, env_seg at %04X:0000 (env_size = %u bytes)\r\n", rmod_seg, RMOD_OFFSET_INPBUFF, *rmod_envseg, envsiz); |
| } |
| |
| _asm { |
| /* set the int22 handler in my PSP to rmod so DOS jumps to rmod after I terminate */ |
| mov bx, 0x0a |
| xor ax, ax |
| mov [bx], ax |
| mov ax, rmod_seg |
| mov [bx+2], ax |
| } |
| |
| for (;;) { |
| int i, argcount; |
| char far *cmdline = MK_FP(rmod_seg, RMOD_OFFSET_INPBUFF + 2); |
| 376,6 → 225,7 |
|---|
| cmd_set(argcount, argvlist, *rmod_envseg); |
| continue; |
| } |
| if (strcmp(argvlist[0], "exit") == 0) break; |
| |
| execvp(argvlist[0], argvlist); |
| |