Subversion Repositories SvarDOS

Rev

Rev 1557 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1556 mateusz.vi 1 
/*
2 
 * replacement for a couple of libc functions
3 
 */
4 
 
5 
#include <i86.h>
6 
#include <stddef.h>
7 
 
8 
#include "libc.h"
9 
 
10 
 
11 
size_t strlen(const char *s) {
12 
  size_t res = 0;
13 
  while (s[res] != 0) res++;
14 
  return(res);
15 
}
16 
 
17 
void bzero(void *ptr, size_t len) {
18 
  while (len > 0) ((char *)ptr)[--len] = 0;
19 
}
20 
 
21 
/* TODO this function does not handle overlapping strings well! */
22 
void far *_fmemmove(void far *dst, const void far *src, size_t len) {
23 
  while (len-- > 0) {
24 
    ((char far *)dst)[len] = ((char far *)src)[len];
25 
  }
26 
  return(dst);
27 
}
28 
 
29 
unsigned short mdr_dos_fclose(unsigned short handle) {
30 
  unsigned short res = 0;
31 
  _asm {
32 
    push bx
33 
 
34 
    mov ah, 0x3e
35 
    mov bx, handle
36 
    int 0x21
37 
    jnc done
38 
    mov res, ax
39 
    done:
40 
 
41 
    pop bx
42 
  }
43 
  return(res);
44 
}
45 
 
46 
 
47 
unsigned short _dos_freemem(unsigned short segn) {
48 
  unsigned short res = 0;
49 
  _asm {
50 
    push es
51 
    mov ah, 0x49
52 
    mov es, segn
53 
    int 0x21
54 
    pop es
55 
    jnc done
56 
    mov res, ax
57 
    done:
58 
  }
59 
  return(res);
60 
}
61 
 
62 
 
63 
unsigned short mdr_dos_allocmem(unsigned short siz) {
64 
  unsigned short segnum = 0;
65 
 
66 
  _asm {
67 
    push bx
68 
 
69 
    mov ah, 0x48
70 
    mov bx, siz
71 
    int 0x21
72 
    jc done
73 
    mov segnum, ax
74 
 
75 
    done:
76 
 
77 
    pop bx
78 
  }
79 
 
80 
  return(segnum);
81 
}
82 
 
83 
 
1557 mateusz.vi 84 
unsigned short mdr_dos_resizeblock(unsigned short siz, unsigned short segn) {
1556 mateusz.vi 85 
  unsigned short res = 0;
86 
 
87 
  _asm {
88 
    push bx
89 
    push es
90 
 
91 
    mov ah, 0x4a
92 
    mov bx, siz
93 
    mov es, segn
94 
    int 0x21
95 
    jnc done
96 
    mov res, ax
97 
 
98 
    done:
99 
 
100 
    pop es
101 
    pop bx
102 
  }
103 
 
104 
  return(res);
105 
}
106 
 
107 
 
108 
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 resax = 0;
111 
  unsigned short buf_off = FP_OFF(buf);
112 
  unsigned short buf_seg = FP_SEG(buf);
113 
 
114 
  _asm {
115 
    push bx,
116 
    push cx
117 
    push dx
118 
 
119 
    mov ah, 0x3f
120 
    mov bx, handle
121 
    mov cx, count
122 
    mov dx, buf_off
123 
    push ds
124 
    mov ds, buf_seg
125 
    int 0x21
126 
    pop ds
127 
 
128 
    jnc done
129 
    mov res, ax
130 
 
131 
    done:
132 
    mov resax, ax
133 
 
134 
    pop dx
135 
    pop cx
136 
    pop bx
137 
  }
138 
 
139 
  *bytes = resax;
140 
  return(res);
141 
}
142 
 
143 
 
144 
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 resax = 0;
147 
  unsigned short buf_seg = FP_SEG(buf);
148 
  unsigned short buf_off = FP_OFF(buf);
149 
 
150 
  _asm {
151 
    push bx
152 
    push cx
153 
    push dx
154 
 
155 
    mov ah, 0x40
156 
    mov bx, handle
157 
    mov cx, count
158 
    mov dx, buf_off
159 
    push ds
160 
    mov ds, buf_seg
161 
 
162 
    int 0x21
163 
    pop ds
164 
    jnc done
165 
    mov res, ax
166 
 
167 
    done:
168 
    mov resax, ax
169 
 
170 
    pop dx
171 
    pop cx
172 
    pop bx
173 
  }
174 
 
175 
  *bytes = resax;
176 
  return(res);
177 
}