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) {
  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;
  _asm {
    push cx
    push dx
 
    mov ax, 0x3d00
    mov dx, fname
    xor cl, cl
    int 0x21
    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 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 1559	Rev 1560
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	`size_t res = 0;`
13	`while (s[res] != 0) res++;`	13	`while (s[res] != 0) res++;`
14	`return(res);`	14	`return(res);`
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_fopen(const char fname, unsigned short fhandle) {`
-		30	`unsigned short res = 0;`
-		31	`unsigned short handle = 0;`
-		32	`_asm {`
-		33	`push cx`
-		34	`push dx`
-		35
-		36	`mov ax, 0x3d00`
-		37	`mov dx, fname`
-		38	`xor cl, cl`
-		39	`int 0x21`
-		40	`jc err`
-		41	`mov handle, ax`
-		42	`jmp done`
-		43	`err:`
-		44	`mov res, ax`
-		45	`done:`
-		46
-		47	`pop dx`
-		48	`pop cx`
-		49	`}`
-		50	`*fhandle = handle;`
-		51	`return(res);`
-		52	`}`
-		53
-		54
29	`unsigned short mdr_dos_fclose(unsigned short handle) {`	55	`unsigned short mdr_dos_fclose(unsigned short handle) {`
30	`unsigned short res = 0;`	56	`unsigned short res = 0;`
31	`_asm {`	57	`_asm {`
32	`push bx`	58	`push bx`
33		59
34	`mov ah, 0x3e`	60	`mov ah, 0x3e`
35	`mov bx, handle`	61	`mov bx, handle`
36	`int 0x21`	62	`int 0x21`
37	`jnc done`	63	`jnc done`
38	`mov res, ax`	64	`mov res, ax`
39	`done:`	65	`done:`
40		66
41	`pop bx`	67	`pop bx`
42	`}`	68	`}`
43	`return(res);`	69	`return(res);`
44	`}`	70	`}`
45		71
46		72
47	`unsigned short _dos_freemem(unsigned short segn) {`	73	`unsigned short _dos_freemem(unsigned short segn) {`
48	`unsigned short res = 0;`	74	`unsigned short res = 0;`
49	`_asm {`	75	`_asm {`
50	`push es`	76	`push es`
51	`mov ah, 0x49`	77	`mov ah, 0x49`
52	`mov es, segn`	78	`mov es, segn`
53	`int 0x21`	79	`int 0x21`
54	`pop es`	80	`pop es`
55	`jnc done`	81	`jnc done`
56	`mov res, ax`	82	`mov res, ax`
57	`done:`	83	`done:`
58	`}`	84	`}`
59	`return(res);`	85	`return(res);`
60	`}`	86	`}`
61		87
62		88
63	`unsigned short mdr_dos_allocmem(unsigned short siz) {`	89	`unsigned short mdr_dos_allocmem(unsigned short siz) {`
64	`unsigned short segnum = 0;`	90	`unsigned short segnum = 0;`
65		91
66	`_asm {`	92	`_asm {`
67	`push bx`	93	`push bx`
68		94
69	`mov ah, 0x48`	95	`mov ah, 0x48`
70	`mov bx, siz`	96	`mov bx, siz`
71	`int 0x21`	97	`int 0x21`
72	`jc done`	98	`jc done`
73	`mov segnum, ax`	99	`mov segnum, ax`
74		100
75	`done:`	101	`done:`
76		102
77	`pop bx`	103	`pop bx`
78	`}`	104	`}`
79		105
80	`return(segnum);`	106	`return(segnum);`
81	`}`	107	`}`
82		108
83		109
84	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`	110	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`
85	`unsigned short res = 0;`	111	`unsigned short res = 0;`
86		112
87	`_asm {`	113	`_asm {`
88	`push bx`	114	`push bx`
89	`push es`	115	`push es`
90		116
91	`mov ah, 0x4a`	117	`mov ah, 0x4a`
92	`mov bx, siz`	118	`mov bx, siz`
93	`mov es, segn`	119	`mov es, segn`
94	`int 0x21`	120	`int 0x21`
95	`jnc done`	121	`jnc done`
96	`mov res, ax`	122	`mov res, ax`
97		123
98	`done:`	124	`done:`
99		125
100	`pop es`	126	`pop es`
101	`pop bx`	127	`pop bx`
102	`}`	128	`}`
103		129
104	`return(res);`	130	`return(res);`
105	`}`	131	`}`
106		132
107		133
108	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`	134	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`
109	`unsigned short res = 0;`	135	`unsigned short res = 0;`
110	`unsigned short resax = 0;`	136	`unsigned short resax = 0;`
111	`unsigned short buf_off = FP_OFF(buf);`	137	`unsigned short buf_off = FP_OFF(buf);`
112	`unsigned short buf_seg = FP_SEG(buf);`	138	`unsigned short buf_seg = FP_SEG(buf);`
113		139
114	`_asm {`	140	`_asm {`
115	`push bx,`	141	`push bx,`
116	`push cx`	142	`push cx`
117	`push dx`	143	`push dx`
118		144
119	`mov ah, 0x3f`	145	`mov ah, 0x3f`
120	`mov bx, handle`	146	`mov bx, handle`
121	`mov cx, count`	147	`mov cx, count`
122	`mov dx, buf_off`	148	`mov dx, buf_off`
123	`push ds`	149	`push ds`
124	`mov ds, buf_seg`	150	`mov ds, buf_seg`
125	`int 0x21`	151	`int 0x21`
126	`pop ds`	152	`pop ds`
127		153
128	`jnc done`	154	`jnc done`
129	`mov res, ax`	155	`mov res, ax`
130		156
131	`done:`	157	`done:`
132	`mov resax, ax`	158	`mov resax, ax`
133		159
134	`pop dx`	160	`pop dx`
135	`pop cx`	161	`pop cx`
136	`pop bx`	162	`pop bx`
137	`}`	163	`}`
138		164
139	`*bytes = resax;`	165	`*bytes = resax;`
140	`return(res);`	166	`return(res);`
141	`}`	167	`}`
142		168
143		169
144	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`	170	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`
145	`unsigned short res = 0;`	171	`unsigned short res = 0;`
146	`unsigned short resax = 0;`	172	`unsigned short resax = 0;`
147	`unsigned short buf_seg = FP_SEG(buf);`	173	`unsigned short buf_seg = FP_SEG(buf);`
148	`unsigned short buf_off = FP_OFF(buf);`	174	`unsigned short buf_off = FP_OFF(buf);`
149		175
150	`_asm {`	176	`_asm {`
151	`push bx`	177	`push bx`
152	`push cx`	178	`push cx`
153	`push dx`	179	`push dx`
154		180
155	`mov ah, 0x40`	181	`mov ah, 0x40`
156	`mov bx, handle`	182	`mov bx, handle`
157	`mov cx, count`	183	`mov cx, count`
158	`mov dx, buf_off`	184	`mov dx, buf_off`
159	`push ds`	185	`push ds`
160	`mov ds, buf_seg`	186	`mov ds, buf_seg`
161		187
162	`int 0x21`	188	`int 0x21`
163	`pop ds`	189	`pop ds`
164	`jnc done`	190	`jnc done`
165	`mov res, ax`	191	`mov res, ax`
166		192
167	`done:`	193	`done:`
168	`mov resax, ax`	194	`mov resax, ax`
169		195
170	`pop dx`	196	`pop dx`
171	`pop cx`	197	`pop cx`
172	`pop bx`	198	`pop bx`
173	`}`	199	`}`
174		200
175	`*bytes = resax;`	201	`*bytes = resax;`
176	`return(res);`	202	`return(res);`
177	`}`	203	`}`
178		204

Subversion Repositories SvarDOS

(root)/sved/trunk/libc.c – Rev 1559 → 1560