WebSVN – SvarDOS – Diff – /sved/trunk/libc.c


/*
 * replacement for a couple of libc functions
 */
 
#include <i86.h>
#include <stddef.h>
 
#include "libc.h"
 
 
size_t strlen(const char *s) {
  const char *ptr = s;
  while (*ptr != 0) ptr++;
  return(ptr - s);
}
 
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_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 res = 0;
 
  _asm {
    push bx
    push es
 
    mov ah, 0x4a
    mov bx, siz
    mov es, segn
    int 0x21
    jnc done
    mov res, ax
 
    done:
 
    pop es
    pop bx
  }
 
  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);
}
 

Rev 1565	Rev 1566
1	`/*`	1	`/*`
2	`* replacement for a couple of libc functions`	2	`* replacement for a couple of libc functions`
3	`*/`	3	`*/`
4		4
5	`#include <i86.h>`	5	`#include <i86.h>`
6	`#include <stddef.h>`	6	`#include <stddef.h>`
7		7
8	`#include "libc.h"`	8	`#include "libc.h"`
9		9
10		10
11	`size_t strlen(const char *s) {`	11	`size_t strlen(const char *s) {`
12	`size_t res = 0;`	12	`const char *ptr = s;`
13	`while (s[res] != 0) res++;`	13	`while (*ptr != 0) ptr++;`
14	`return(res);`	14	`return(ptr - s);`
15	`}`	15	`}`
16		16
17	`void bzero(void *ptr, size_t len) {`	17	`void bzero(void *ptr, size_t len) {`
18	`while (len > 0) ((char *)ptr)[--len] = 0;`	18	`while (len > 0) ((char *)ptr)[--len] = 0;`
19	`}`	19	`}`
20		20
21	`/* TODO this function does not handle overlapping strings well! */`	21	`/* TODO this function does not handle overlapping strings well! */`
22	`void far _fmemmove(void far dst, const void far *src, size_t len) {`	22	`void far _fmemmove(void far dst, const void far *src, size_t len) {`
23	`while (len-- > 0) {`	23	`while (len-- > 0) {`
24	`((char far )dst)[len] = ((char far )src)[len];`	24	`((char far )dst)[len] = ((char far )src)[len];`
25	`}`	25	`}`
26	`return(dst);`	26	`return(dst);`
27	`}`	27	`}`
28		28
29	`unsigned short mdr_dos_fclose(unsigned short handle) {`	29	`unsigned short mdr_dos_fclose(unsigned short handle) {`
30	`unsigned short res = 0;`	30	`unsigned short res = 0;`
31	`_asm {`	31	`_asm {`
32	`push bx`	32	`push bx`
33		33
34	`mov ah, 0x3e`	34	`mov ah, 0x3e`
35	`mov bx, handle`	35	`mov bx, handle`
36	`int 0x21`	36	`int 0x21`
37	`jnc done`	37	`jnc done`
38	`mov res, ax`	38	`mov res, ax`
39	`done:`	39	`done:`
40		40
41	`pop bx`	41	`pop bx`
42	`}`	42	`}`
43	`return(res);`	43	`return(res);`
44	`}`	44	`}`
45		45
46		46
47	`unsigned short _dos_freemem(unsigned short segn) {`	47	`unsigned short _dos_freemem(unsigned short segn) {`
48	`unsigned short res = 0;`	48	`unsigned short res = 0;`
49	`_asm {`	49	`_asm {`
50	`push es`	50	`push es`
51	`mov ah, 0x49`	51	`mov ah, 0x49`
52	`mov es, segn`	52	`mov es, segn`
53	`int 0x21`	53	`int 0x21`
54	`pop es`	54	`pop es`
55	`jnc done`	55	`jnc done`
56	`mov res, ax`	56	`mov res, ax`
57	`done:`	57	`done:`
58	`}`	58	`}`
59	`return(res);`	59	`return(res);`
60	`}`	60	`}`
61		61
62		62
63	`unsigned short mdr_dos_allocmem(unsigned short siz) {`	63	`unsigned short mdr_dos_allocmem(unsigned short siz) {`
64	`unsigned short segnum = 0;`	64	`unsigned short segnum = 0;`
65		65
66	`_asm {`	66	`_asm {`
67	`push bx`	67	`push bx`
68		68
69	`mov ah, 0x48`	69	`mov ah, 0x48`
70	`mov bx, siz`	70	`mov bx, siz`
71	`int 0x21`	71	`int 0x21`
72	`jc done`	72	`jc done`
73	`mov segnum, ax`	73	`mov segnum, ax`
74		74
75	`done:`	75	`done:`
76		76
77	`pop bx`	77	`pop bx`
78	`}`	78	`}`
79		79
80	`return(segnum);`	80	`return(segnum);`
81	`}`	81	`}`
82		82
83		83
84	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`	84	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`
85	`unsigned short res = 0;`	85	`unsigned short res = 0;`
86		86
87	`_asm {`	87	`_asm {`
88	`push bx`	88	`push bx`
89	`push es`	89	`push es`
90		90
91	`mov ah, 0x4a`	91	`mov ah, 0x4a`
92	`mov bx, siz`	92	`mov bx, siz`
93	`mov es, segn`	93	`mov es, segn`
94	`int 0x21`	94	`int 0x21`
95	`jnc done`	95	`jnc done`
96	`mov res, ax`	96	`mov res, ax`
97		97
98	`done:`	98	`done:`
99		99
100	`pop es`	100	`pop es`
101	`pop bx`	101	`pop bx`
102	`}`	102	`}`
103		103
104	`return(res);`	104	`return(res);`
105	`}`	105	`}`
106		106
107		107
108	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`	108	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`
109	`unsigned short res = 0;`	109	`unsigned short res = 0;`
110	`unsigned short resax = 0;`	110	`unsigned short resax = 0;`
111	`unsigned short buf_off = FP_OFF(buf);`	111	`unsigned short buf_off = FP_OFF(buf);`
112	`unsigned short buf_seg = FP_SEG(buf);`	112	`unsigned short buf_seg = FP_SEG(buf);`
113		113
114	`_asm {`	114	`_asm {`
115	`push bx,`	115	`push bx,`
116	`push cx`	116	`push cx`
117	`push dx`	117	`push dx`
118		118
119	`mov ah, 0x3f`	119	`mov ah, 0x3f`
120	`mov bx, handle`	120	`mov bx, handle`
121	`mov cx, count`	121	`mov cx, count`
122	`mov dx, buf_off`	122	`mov dx, buf_off`
123	`push ds`	123	`push ds`
124	`mov ds, buf_seg`	124	`mov ds, buf_seg`
125	`int 0x21`	125	`int 0x21`
126	`pop ds`	126	`pop ds`
127		127
128	`jnc done`	128	`jnc done`
129	`mov res, ax`	129	`mov res, ax`
130		130
131	`done:`	131	`done:`
132	`mov resax, ax`	132	`mov resax, ax`
133		133
134	`pop dx`	134	`pop dx`
135	`pop cx`	135	`pop cx`
136	`pop bx`	136	`pop bx`
137	`}`	137	`}`
138		138
139	`*bytes = resax;`	139	`*bytes = resax;`
140	`return(res);`	140	`return(res);`
141	`}`	141	`}`
142		142
143		143
144	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`	144	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`
145	`unsigned short res = 0;`	145	`unsigned short res = 0;`
146	`unsigned short resax = 0;`	146	`unsigned short resax = 0;`
147	`unsigned short buf_seg = FP_SEG(buf);`	147	`unsigned short buf_seg = FP_SEG(buf);`
148	`unsigned short buf_off = FP_OFF(buf);`	148	`unsigned short buf_off = FP_OFF(buf);`
149		149
150	`_asm {`	150	`_asm {`
151	`push bx`	151	`push bx`
152	`push cx`	152	`push cx`
153	`push dx`	153	`push dx`
154		154
155	`mov ah, 0x40`	155	`mov ah, 0x40`
156	`mov bx, handle`	156	`mov bx, handle`
157	`mov cx, count`	157	`mov cx, count`
158	`mov dx, buf_off`	158	`mov dx, buf_off`
159	`push ds`	159	`push ds`
160	`mov ds, buf_seg`	160	`mov ds, buf_seg`
161		161
162	`int 0x21`	162	`int 0x21`
163	`pop ds`	163	`pop ds`
164	`jnc done`	164	`jnc done`
165	`mov res, ax`	165	`mov res, ax`
166		166
167	`done:`	167	`done:`
168	`mov resax, ax`	168	`mov resax, ax`
169		169
170	`pop dx`	170	`pop dx`
171	`pop cx`	171	`pop cx`
172	`pop bx`	172	`pop bx`
173	`}`	173	`}`
174		174
175	`*bytes = resax;`	175	`*bytes = resax;`
176	`return(res);`	176	`return(res);`
177	`}`	177	`}`
178		178

Subversion Repositories SvarDOS

(root)/sved/trunk/libc.c @ 1566 – Rev 1565 → 1566