| 0,0 → 1,211 |
|---|
| /* |
| * replacement for a couple of libc functions |
| */ |
| |
| #include <i86.h> |
| #include <stddef.h> |
| |
| #include "libc.h" |
| |
| |
| size_t strlen(const char *s) { |
| size_t res = 0; |
| while (s[res] != 0) res++; |
| return(res); |
| } |
| |
| void bzero(void *ptr, size_t len) { |
| while (len > 0) ((char *)ptr)[--len] = 0; |
| } |
| |
| /* TODO this function does not handle overlapping strings well! */ |
| void far *_fmemmove(void far *dst, const void far *src, size_t len) { |
| while (len-- > 0) { |
| ((char far *)dst)[len] = ((char far *)src)[len]; |
| } |
| return(dst); |
| } |
| |
| unsigned short mdr_dos_fopen(const char *fname, unsigned short *fhandle) { |
| unsigned short res = 0; |
| unsigned short handle = 0; |
| unsigned short fname_seg = FP_SEG(fname); |
| unsigned short fname_off = FP_OFF(fname); |
| _asm { |
| push cx |
| push dx |
| |
| mov ax, 0x3d00 |
| mov dx, fname_off |
| xor cl, cl |
| push ds |
| mov ds, fname_seg |
| int 0x21 |
| pop ds |
| jc err |
| mov handle, ax |
| jmp done |
| err: |
| mov res, ax |
| done: |
| |
| pop dx |
| pop cx |
| } |
| *fhandle = handle; |
| return(res); |
| } |
| |
| |
| unsigned short mdr_dos_fclose(unsigned short handle) { |
| unsigned short res = 0; |
| _asm { |
| push bx |
| |
| mov ah, 0x3e |
| mov bx, handle |
| int 0x21 |
| jnc done |
| mov res, ax |
| done: |
| |
| pop bx |
| } |
| return(res); |
| } |
| |
| |
| unsigned short _dos_freemem(unsigned short segn) { |
| unsigned short res = 0; |
| _asm { |
| push es |
| mov ah, 0x49 |
| mov es, segn |
| int 0x21 |
| pop es |
| jnc done |
| mov res, ax |
| done: |
| } |
| return(res); |
| } |
| |
| |
| unsigned short mdr_dos_allocmem(unsigned short siz) { |
| unsigned short segnum = 0; |
| |
| _asm { |
| push bx |
| |
| mov ah, 0x48 |
| mov bx, siz |
| int 0x21 |
| jc done |
| mov segnum, ax |
| |
| done: |
| |
| pop bx |
| } |
| |
| return(segnum); |
| } |
| |
| |
| unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn, unsigned short *maxsiz) { |
| unsigned short resbx = 0; |
| unsigned short res = 0; |
| |
| _asm { |
| push bx |
| push es |
| |
| mov ah, 0x4a |
| mov bx, siz |
| mov es, segn |
| int 0x21 |
| jnc done |
| mov resbx, bx |
| mov res, ax |
| |
| done: |
| |
| pop es |
| pop bx |
| } |
| |
| *maxsiz = resbx; |
| return(res); |
| } |
| |
| |
| unsigned short mdr_dos_read(unsigned short handle, void far *buf, unsigned short count, unsigned short *bytes) { |
| unsigned short res = 0; |
| unsigned short resax = 0; |
| unsigned short buf_off = FP_OFF(buf); |
| unsigned short buf_seg = FP_SEG(buf); |
| |
| _asm { |
| push bx, |
| push cx |
| push dx |
| |
| mov ah, 0x3f |
| mov bx, handle |
| mov cx, count |
| mov dx, buf_off |
| push ds |
| mov ds, buf_seg |
| int 0x21 |
| pop ds |
| |
| jnc done |
| mov res, ax |
| |
| done: |
| mov resax, ax |
| |
| pop dx |
| pop cx |
| pop bx |
| } |
| |
| *bytes = resax; |
| return(res); |
| } |
| |
| |
| unsigned short mdr_dos_write(unsigned short handle, const void far *buf, unsigned short count, unsigned short *bytes) { |
| unsigned short res = 0; |
| unsigned short resax = 0; |
| unsigned short buf_seg = FP_SEG(buf); |
| unsigned short buf_off = FP_OFF(buf); |
| |
| _asm { |
| push bx |
| push cx |
| push dx |
| |
| mov ah, 0x40 |
| mov bx, handle |
| mov cx, count |
| mov dx, buf_off |
| push ds |
| mov ds, buf_seg |
| |
| int 0x21 |
| pop ds |
| jnc done |
| mov res, ax |
| |
| done: |
| mov resax, ax |
| |
| pop dx |
| pop cx |
| pop bx |
| } |
| |
| *bytes = resax; |
| return(res); |
| } |