1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
#include "stdio.h"
struct opaque_t {
union {
const char * p;
int fd;
};
uint8_t bsize;
char backbuffer[3];
};
static int str_getc(void * _opaque) {
struct opaque_t * opaque = (struct opaque_t *) _opaque;
int r;
if (opaque->bsize)
return opaque->backbuffer[--(opaque->bsize)];
r = *(opaque->p++);
return r ? r : EOF;
}
static int file_getc(void * _opaque) {
struct opaque_t * opaque = (struct opaque_t *) _opaque;
uint8_t v;
if (opaque->bsize)
return opaque->backbuffer[--(opaque->bsize)];
if (read(opaque->fd, &v, 1) != 1)
return EOF;
return v;
}
static void scanf_ungetc(void * _opaque, int c) {
struct opaque_t * opaque = (struct opaque_t *) _opaque;
if (opaque->bsize < sizeof(opaque->backbuffer))
opaque->backbuffer[opaque->bsize++] = c;
}
int vsscanf(const char * str, const char * format, va_list ap) {
struct opaque_t opaque;
opaque.p = str;
opaque.bsize = 0;
return vxscanf(str_getc, scanf_ungetc, &opaque, format, ap);
}
int vdscanf(int fd, const char * format, va_list ap) {
struct opaque_t opaque;
opaque.fd = fd;
opaque.bsize = 0;
return vxscanf(file_getc, scanf_ungetc, &opaque, format, ap);
}
|
