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 fmemmove(void far *dst, const void far *src, size_t len) {
  while (len-- > 0) {
    *(char far *)dst = *(char far *)src;
    dst = (char far *)dst + 1;
    src = (char far *)src + 1;
  }
 
}
 
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 1566	Rev 1568
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	`const char *ptr = s;`	12	`const char *ptr = s;`
13	`while (*ptr != 0) ptr++;`	13	`while (*ptr != 0) ptr++;`
14	`return(ptr - s);`	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 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 = (char far )src;`
-		25	`dst = (char far *)dst + 1;`
-		26	`src = (char far *)src + 1;`
25	`}`	27	`}`
26	`return(dst);`	-
27	`}`	28	`}`
28		29
29	`unsigned short mdr_dos_fclose(unsigned short handle) {`	30	`unsigned short mdr_dos_fclose(unsigned short handle) {`
30	`unsigned short res = 0;`	31	`unsigned short res = 0;`
31	`_asm {`	32	`_asm {`
32	`push bx`	33	`push bx`
33		34
34	`mov ah, 0x3e`	35	`mov ah, 0x3e`
35	`mov bx, handle`	36	`mov bx, handle`
36	`int 0x21`	37	`int 0x21`
37	`jnc done`	38	`jnc done`
38	`mov res, ax`	39	`mov res, ax`
39	`done:`	40	`done:`
40		41
41	`pop bx`	42	`pop bx`
42	`}`	43	`}`
43	`return(res);`	44	`return(res);`
44	`}`	45	`}`
45		46
46		47
47	`unsigned short _dos_freemem(unsigned short segn) {`	48	`unsigned short _dos_freemem(unsigned short segn) {`
48	`unsigned short res = 0;`	49	`unsigned short res = 0;`
49	`_asm {`	50	`_asm {`
50	`push es`	51	`push es`
51	`mov ah, 0x49`	52	`mov ah, 0x49`
52	`mov es, segn`	53	`mov es, segn`
53	`int 0x21`	54	`int 0x21`
54	`pop es`	55	`pop es`
55	`jnc done`	56	`jnc done`
56	`mov res, ax`	57	`mov res, ax`
57	`done:`	58	`done:`
58	`}`	59	`}`
59	`return(res);`	60	`return(res);`
60	`}`	61	`}`
61		62
62		63
63	`unsigned short mdr_dos_allocmem(unsigned short siz) {`	64	`unsigned short mdr_dos_allocmem(unsigned short siz) {`
64	`unsigned short segnum = 0;`	65	`unsigned short segnum = 0;`
65		66
66	`_asm {`	67	`_asm {`
67	`push bx`	68	`push bx`
68		69
69	`mov ah, 0x48`	70	`mov ah, 0x48`
70	`mov bx, siz`	71	`mov bx, siz`
71	`int 0x21`	72	`int 0x21`
72	`jc done`	73	`jc done`
73	`mov segnum, ax`	74	`mov segnum, ax`
74		75
75	`done:`	76	`done:`
76		77
77	`pop bx`	78	`pop bx`
78	`}`	79	`}`
79		80
80	`return(segnum);`	81	`return(segnum);`
81	`}`	82	`}`
82		83
83		84
84	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`	85	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`
85	`unsigned short res = 0;`	86	`unsigned short res = 0;`
86		87
87	`_asm {`	88	`_asm {`
88	`push bx`	89	`push bx`
89	`push es`	90	`push es`
90		91
91	`mov ah, 0x4a`	92	`mov ah, 0x4a`
92	`mov bx, siz`	93	`mov bx, siz`
93	`mov es, segn`	94	`mov es, segn`
94	`int 0x21`	95	`int 0x21`
95	`jnc done`	96	`jnc done`
96	`mov res, ax`	97	`mov res, ax`
97		98
98	`done:`	99	`done:`
99		100
100	`pop es`	101	`pop es`
101	`pop bx`	102	`pop bx`
102	`}`	103	`}`
103		104
104	`return(res);`	105	`return(res);`
105	`}`	106	`}`
106		107
107		108
108	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`	109	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`
109	`unsigned short res = 0;`	110	`unsigned short res = 0;`
110	`unsigned short resax = 0;`	111	`unsigned short resax = 0;`
111	`unsigned short buf_off = FP_OFF(buf);`	112	`unsigned short buf_off = FP_OFF(buf);`
112	`unsigned short buf_seg = FP_SEG(buf);`	113	`unsigned short buf_seg = FP_SEG(buf);`
113		114
114	`_asm {`	115	`_asm {`
115	`push bx,`	116	`push bx,`
116	`push cx`	117	`push cx`
117	`push dx`	118	`push dx`
118		119
119	`mov ah, 0x3f`	120	`mov ah, 0x3f`
120	`mov bx, handle`	121	`mov bx, handle`
121	`mov cx, count`	122	`mov cx, count`
122	`mov dx, buf_off`	123	`mov dx, buf_off`
123	`push ds`	124	`push ds`
124	`mov ds, buf_seg`	125	`mov ds, buf_seg`
125	`int 0x21`	126	`int 0x21`
126	`pop ds`	127	`pop ds`
127		128
128	`jnc done`	129	`jnc done`
129	`mov res, ax`	130	`mov res, ax`
130		131
131	`done:`	132	`done:`
132	`mov resax, ax`	133	`mov resax, ax`
133		134
134	`pop dx`	135	`pop dx`
135	`pop cx`	136	`pop cx`
136	`pop bx`	137	`pop bx`
137	`}`	138	`}`
138		139
139	`*bytes = resax;`	140	`*bytes = resax;`
140	`return(res);`	141	`return(res);`
141	`}`	142	`}`
142		143
143		144
144	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`	145	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`
145	`unsigned short res = 0;`	146	`unsigned short res = 0;`
146	`unsigned short resax = 0;`	147	`unsigned short resax = 0;`
147	`unsigned short buf_seg = FP_SEG(buf);`	148	`unsigned short buf_seg = FP_SEG(buf);`
148	`unsigned short buf_off = FP_OFF(buf);`	149	`unsigned short buf_off = FP_OFF(buf);`
149		150
150	`_asm {`	151	`_asm {`
151	`push bx`	152	`push bx`
152	`push cx`	153	`push cx`
153	`push dx`	154	`push dx`
154		155
155	`mov ah, 0x40`	156	`mov ah, 0x40`
156	`mov bx, handle`	157	`mov bx, handle`
157	`mov cx, count`	158	`mov cx, count`
158	`mov dx, buf_off`	159	`mov dx, buf_off`
159	`push ds`	160	`push ds`
160	`mov ds, buf_seg`	161	`mov ds, buf_seg`
161		162
162	`int 0x21`	163	`int 0x21`
163	`pop ds`	164	`pop ds`
164	`jnc done`	165	`jnc done`
165	`mov res, ax`	166	`mov res, ax`
166		167
167	`done:`	168	`done:`
168	`mov resax, ax`	169	`mov resax, ax`
169		170
170	`pop dx`	171	`pop dx`
171	`pop cx`	172	`pop cx`
172	`pop bx`	173	`pop bx`
173	`}`	174	`}`
174		175
175	`*bytes = resax;`	176	`*bytes = resax;`
176	`return(res);`	177	`return(res);`
177	`}`	178	`}`
178		179

Subversion Repositories SvarDOS

(root)/sved/trunk/libc.c – Rev 1566 → 1568