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) {
  char *p = ptr;
  while (len > 0) {
    *p = 0;
    p++;
    len--;
  }
}
 
/* 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 1568	Rev 1571
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	`char *p = ptr;`
18	`while (len > 0) ((char *)ptr)[--len] = 0;`	19	`while (len > 0) {`
-		20	`*p = 0;`
-		21	`p++;`
-		22	`len--;`
-		23	`}`
19	`}`	24	`}`
20		25
21	`/* TODO this function does not handle overlapping strings well! */`	26	`/* TODO this function does not handle overlapping strings well! */`
22	`void fmemmove(void far dst, const void far src, size_t len) {`	27	`void fmemmove(void far dst, const void far src, size_t len) {`
23	`while (len-- > 0) {`	28	`while (len-- > 0) {`
24	`(char far )dst = (char far )src;`	29	`(char far )dst = (char far )src;`
25	`dst = (char far *)dst + 1;`	30	`dst = (char far *)dst + 1;`
26	`src = (char far *)src + 1;`	31	`src = (char far *)src + 1;`
27	`}`	32	`}`
28	`}`	33	`}`
29		34
30	`unsigned short mdr_dos_fclose(unsigned short handle) {`	35	`unsigned short mdr_dos_fclose(unsigned short handle) {`
31	`unsigned short res = 0;`	36	`unsigned short res = 0;`
32	`_asm {`	37	`_asm {`
33	`push bx`	38	`push bx`
34		39
35	`mov ah, 0x3e`	40	`mov ah, 0x3e`
36	`mov bx, handle`	41	`mov bx, handle`
37	`int 0x21`	42	`int 0x21`
38	`jnc done`	43	`jnc done`
39	`mov res, ax`	44	`mov res, ax`
40	`done:`	45	`done:`
41		46
42	`pop bx`	47	`pop bx`
43	`}`	48	`}`
44	`return(res);`	49	`return(res);`
45	`}`	50	`}`
46		51
47		52
48	`unsigned short _dos_freemem(unsigned short segn) {`	53	`unsigned short _dos_freemem(unsigned short segn) {`
49	`unsigned short res = 0;`	54	`unsigned short res = 0;`
50	`_asm {`	55	`_asm {`
51	`push es`	56	`push es`
52	`mov ah, 0x49`	57	`mov ah, 0x49`
53	`mov es, segn`	58	`mov es, segn`
54	`int 0x21`	59	`int 0x21`
55	`pop es`	60	`pop es`
56	`jnc done`	61	`jnc done`
57	`mov res, ax`	62	`mov res, ax`
58	`done:`	63	`done:`
59	`}`	64	`}`
60	`return(res);`	65	`return(res);`
61	`}`	66	`}`
62		67
63		68
64	`unsigned short mdr_dos_allocmem(unsigned short siz) {`	69	`unsigned short mdr_dos_allocmem(unsigned short siz) {`
65	`unsigned short segnum = 0;`	70	`unsigned short segnum = 0;`
66		71
67	`_asm {`	72	`_asm {`
68	`push bx`	73	`push bx`
69		74
70	`mov ah, 0x48`	75	`mov ah, 0x48`
71	`mov bx, siz`	76	`mov bx, siz`
72	`int 0x21`	77	`int 0x21`
73	`jc done`	78	`jc done`
74	`mov segnum, ax`	79	`mov segnum, ax`
75		80
76	`done:`	81	`done:`
77		82
78	`pop bx`	83	`pop bx`
79	`}`	84	`}`
80		85
81	`return(segnum);`	86	`return(segnum);`
82	`}`	87	`}`
83		88
84		89
85	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`	90	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`
86	`unsigned short res = 0;`	91	`unsigned short res = 0;`
87		92
88	`_asm {`	93	`_asm {`
89	`push bx`	94	`push bx`
90	`push es`	95	`push es`
91		96
92	`mov ah, 0x4a`	97	`mov ah, 0x4a`
93	`mov bx, siz`	98	`mov bx, siz`
94	`mov es, segn`	99	`mov es, segn`
95	`int 0x21`	100	`int 0x21`
96	`jnc done`	101	`jnc done`
97	`mov res, ax`	102	`mov res, ax`
98		103
99	`done:`	104	`done:`
100		105
101	`pop es`	106	`pop es`
102	`pop bx`	107	`pop bx`
103	`}`	108	`}`
104		109
105	`return(res);`	110	`return(res);`
106	`}`	111	`}`
107		112
108		113
109	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`	114	`unsigned short mdr_dos_read(unsigned short handle, void far buf, unsigned short count, unsigned short bytes) {`
110	`unsigned short res = 0;`	115	`unsigned short res = 0;`
111	`unsigned short resax = 0;`	116	`unsigned short resax = 0;`
112	`unsigned short buf_off = FP_OFF(buf);`	117	`unsigned short buf_off = FP_OFF(buf);`
113	`unsigned short buf_seg = FP_SEG(buf);`	118	`unsigned short buf_seg = FP_SEG(buf);`
114		119
115	`_asm {`	120	`_asm {`
116	`push bx,`	121	`push bx,`
117	`push cx`	122	`push cx`
118	`push dx`	123	`push dx`
119		124
120	`mov ah, 0x3f`	125	`mov ah, 0x3f`
121	`mov bx, handle`	126	`mov bx, handle`
122	`mov cx, count`	127	`mov cx, count`
123	`mov dx, buf_off`	128	`mov dx, buf_off`
124	`push ds`	129	`push ds`
125	`mov ds, buf_seg`	130	`mov ds, buf_seg`
126	`int 0x21`	131	`int 0x21`
127	`pop ds`	132	`pop ds`
128		133
129	`jnc done`	134	`jnc done`
130	`mov res, ax`	135	`mov res, ax`
131		136
132	`done:`	137	`done:`
133	`mov resax, ax`	138	`mov resax, ax`
134		139
135	`pop dx`	140	`pop dx`
136	`pop cx`	141	`pop cx`
137	`pop bx`	142	`pop bx`
138	`}`	143	`}`
139		144
140	`*bytes = resax;`	145	`*bytes = resax;`
141	`return(res);`	146	`return(res);`
142	`}`	147	`}`
143		148
144		149
145	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`	150	`unsigned short mdr_dos_write(unsigned short handle, const void far buf, unsigned short count, unsigned short bytes) {`
146	`unsigned short res = 0;`	151	`unsigned short res = 0;`
147	`unsigned short resax = 0;`	152	`unsigned short resax = 0;`
148	`unsigned short buf_seg = FP_SEG(buf);`	153	`unsigned short buf_seg = FP_SEG(buf);`
149	`unsigned short buf_off = FP_OFF(buf);`	154	`unsigned short buf_off = FP_OFF(buf);`
150		155
151	`_asm {`	156	`_asm {`
152	`push bx`	157	`push bx`
153	`push cx`	158	`push cx`
154	`push dx`	159	`push dx`
155		160
156	`mov ah, 0x40`	161	`mov ah, 0x40`
157	`mov bx, handle`	162	`mov bx, handle`
158	`mov cx, count`	163	`mov cx, count`
159	`mov dx, buf_off`	164	`mov dx, buf_off`
160	`push ds`	165	`push ds`
161	`mov ds, buf_seg`	166	`mov ds, buf_seg`
162		167
163	`int 0x21`	168	`int 0x21`
164	`pop ds`	169	`pop ds`
165	`jnc done`	170	`jnc done`
166	`mov res, ax`	171	`mov res, ax`
167		172
168	`done:`	173	`done:`
169	`mov resax, ax`	174	`mov resax, ax`
170		175
171	`pop dx`	176	`pop dx`
172	`pop cx`	177	`pop cx`
173	`pop bx`	178	`pop bx`
174	`}`	179	`}`
175		180
176	`*bytes = resax;`	181	`*bytes = resax;`
177	`return(res);`	182	`return(res);`
178	`}`	183	`}`
179		184

Subversion Repositories SvarDOS

(root)/sved/trunk/libc.c – Rev 1568 → 1571