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 1556	Rev 1557
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) {`	29	`unsigned short mdr_dos_fopen(const char fname, unsigned short fhandle) {`
30	`unsigned short res = 0;`	30	`unsigned short res = 0;`
31	`unsigned short handle = 0;`	31	`unsigned short handle = 0;`
32	`unsigned short fname_seg = FP_SEG(fname);`	-
33	`unsigned short fname_off = FP_OFF(fname);`	-
34	`_asm {`	32	`_asm {`
35	`push cx`	33	`push cx`
36	`push dx`	34	`push dx`
37		35
38	`mov ax, 0x3d00`	36	`mov ax, 0x3d00`
39	`mov dx, fname_off`	37	`mov dx, fname`
40	`xor cl, cl`	38	`xor cl, cl`
41	`push ds`	-
42	`mov ds, fname_seg`	-
43	`int 0x21`	39	`int 0x21`
44	`pop ds`	-
45	`jc err`	40	`jc err`
46	`mov handle, ax`	41	`mov handle, ax`
47	`jmp done`	42	`jmp done`
48	`err:`	43	`err:`
49	`mov res, ax`	44	`mov res, ax`
50	`done:`	45	`done:`
51		46
52	`pop dx`	47	`pop dx`
53	`pop cx`	48	`pop cx`
54	`}`	49	`}`
55	`*fhandle = handle;`	50	`*fhandle = handle;`
56	`return(res);`	51	`return(res);`
57	`}`	52	`}`
58		53
59		54
60	`unsigned short mdr_dos_fclose(unsigned short handle) {`	55	`unsigned short mdr_dos_fclose(unsigned short handle) {`
61	`unsigned short res = 0;`	56	`unsigned short res = 0;`
62	`_asm {`	57	`_asm {`
63	`push bx`	58	`push bx`
64		59
65	`mov ah, 0x3e`	60	`mov ah, 0x3e`
66	`mov bx, handle`	61	`mov bx, handle`
67	`int 0x21`	62	`int 0x21`
68	`jnc done`	63	`jnc done`
69	`mov res, ax`	64	`mov res, ax`
70	`done:`	65	`done:`
71		66
72	`pop bx`	67	`pop bx`
73	`}`	68	`}`
74	`return(res);`	69	`return(res);`
75	`}`	70	`}`
76		71
77		72
78	`unsigned short _dos_freemem(unsigned short segn) {`	73	`unsigned short _dos_freemem(unsigned short segn) {`
79	`unsigned short res = 0;`	74	`unsigned short res = 0;`
80	`_asm {`	75	`_asm {`
81	`push es`	76	`push es`
82	`mov ah, 0x49`	77	`mov ah, 0x49`
83	`mov es, segn`	78	`mov es, segn`
84	`int 0x21`	79	`int 0x21`
85	`pop es`	80	`pop es`
86	`jnc done`	81	`jnc done`
87	`mov res, ax`	82	`mov res, ax`
88	`done:`	83	`done:`
89	`}`	84	`}`
90	`return(res);`	85	`return(res);`
91	`}`	86	`}`
92		87
93		88
94	`unsigned short mdr_dos_allocmem(unsigned short siz) {`	89	`unsigned short mdr_dos_allocmem(unsigned short siz) {`
95	`unsigned short segnum = 0;`	90	`unsigned short segnum = 0;`
96		91
97	`_asm {`	92	`_asm {`
98	`push bx`	93	`push bx`
99		94
100	`mov ah, 0x48`	95	`mov ah, 0x48`
101	`mov bx, siz`	96	`mov bx, siz`
102	`int 0x21`	97	`int 0x21`
103	`jc done`	98	`jc done`
104	`mov segnum, ax`	99	`mov segnum, ax`
105		100
106	`done:`	101	`done:`
107		102
108	`pop bx`	103	`pop bx`
109	`}`	104	`}`
110		105
111	`return(segnum);`	106	`return(segnum);`
112	`}`	107	`}`
113		108
114		109
115	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn, unsigned short *maxsiz) {`	110	`unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {`
116	`unsigned short resbx = 0;`	-
117	`unsigned short res = 0;`	111	`unsigned short res = 0;`
118		112
119	`_asm {`	113	`_asm {`
120	`push bx`	114	`push bx`
121	`push es`	115	`push es`
122		116
123	`mov ah, 0x4a`	117	`mov ah, 0x4a`
124	`mov bx, siz`	118	`mov bx, siz`
125	`mov es, segn`	119	`mov es, segn`
126	`int 0x21`	120	`int 0x21`
127	`jnc done`	121	`jnc done`
128	`mov resbx, bx`	-
129	`mov res, ax`	122	`mov res, ax`
130		123
131	`done:`	124	`done:`
132		125
133	`pop es`	126	`pop es`
134	`pop bx`	127	`pop bx`
135	`}`	128	`}`
136		129
137	`*maxsiz = resbx;`	-
138	`return(res);`	130	`return(res);`
139	`}`	131	`}`
140		132
141		133
142	`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) {`
143	`unsigned short res = 0;`	135	`unsigned short res = 0;`
144	`unsigned short resax = 0;`	136	`unsigned short resax = 0;`
145	`unsigned short buf_off = FP_OFF(buf);`	137	`unsigned short buf_off = FP_OFF(buf);`
146	`unsigned short buf_seg = FP_SEG(buf);`	138	`unsigned short buf_seg = FP_SEG(buf);`
147		139
148	`_asm {`	140	`_asm {`
149	`push bx,`	141	`push bx,`
150	`push cx`	142	`push cx`
151	`push dx`	143	`push dx`
152		144
153	`mov ah, 0x3f`	145	`mov ah, 0x3f`
154	`mov bx, handle`	146	`mov bx, handle`
155	`mov cx, count`	147	`mov cx, count`
156	`mov dx, buf_off`	148	`mov dx, buf_off`
157	`push ds`	149	`push ds`
158	`mov ds, buf_seg`	150	`mov ds, buf_seg`
159	`int 0x21`	151	`int 0x21`
160	`pop ds`	152	`pop ds`
161		153
162	`jnc done`	154	`jnc done`
163	`mov res, ax`	155	`mov res, ax`
164		156
165	`done:`	157	`done:`
166	`mov resax, ax`	158	`mov resax, ax`
167		159
168	`pop dx`	160	`pop dx`
169	`pop cx`	161	`pop cx`
170	`pop bx`	162	`pop bx`
171	`}`	163	`}`
172		164
173	`*bytes = resax;`	165	`*bytes = resax;`
174	`return(res);`	166	`return(res);`
175	`}`	167	`}`
176		168
177		169
178	`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) {`
179	`unsigned short res = 0;`	171	`unsigned short res = 0;`
180	`unsigned short resax = 0;`	172	`unsigned short resax = 0;`
181	`unsigned short buf_seg = FP_SEG(buf);`	173	`unsigned short buf_seg = FP_SEG(buf);`
182	`unsigned short buf_off = FP_OFF(buf);`	174	`unsigned short buf_off = FP_OFF(buf);`
183		175
184	`_asm {`	176	`_asm {`
185	`push bx`	177	`push bx`
186	`push cx`	178	`push cx`
187	`push dx`	179	`push dx`
188		180
189	`mov ah, 0x40`	181	`mov ah, 0x40`
190	`mov bx, handle`	182	`mov bx, handle`
191	`mov cx, count`	183	`mov cx, count`
192	`mov dx, buf_off`	184	`mov dx, buf_off`
193	`push ds`	185	`push ds`
194	`mov ds, buf_seg`	186	`mov ds, buf_seg`
195		187
196	`int 0x21`	188	`int 0x21`
197	`pop ds`	189	`pop ds`
198	`jnc done`	190	`jnc done`
199	`mov res, ax`	191	`mov res, ax`
200		192
201	`done:`	193	`done:`
202	`mov resax, ax`	194	`mov resax, ax`
203		195
204	`pop dx`	196	`pop dx`
205	`pop cx`	197	`pop cx`
206	`pop bx`	198	`pop bx`
207	`}`	199	`}`
208		200
209	`*bytes = resax;`	201	`*bytes = resax;`
210	`return(res);`	202	`return(res);`
211	`}`	203	`}`
212		204

Subversion Repositories SvarDOS

(root)/sved/trunk/libc.c/ @ 1559 – Rev 1556 → 1557