blob: f6a9e9343c77ded0b62765a8aab4f1ff8ec4669e (
plain)
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
|
/* ########################################################### */
/* This Software is licensed under the GPL licensed Version 2, */
/* please read http://www.gnu.org/copyleft/gpl.html. */
/* ########################################################### */
/* ************************************************************************* */
/* Custom fgetc/ungetc implementation able to unget more than one character. */
/* ************************************************************************* */
#include <stdio.h>
#include "fgetc.h"
enum
{
GETC_BUFF_SIZE = 16
};
static unsigned char getc_buffer[GETC_BUFF_SIZE] = { '\0' };
static long next_buffer_pos = 0; /* Next free position in the getc buffer. */
/* ======================================== */
/* Gets a (possibly pushed-back) character. */
/* ======================================== */
int
my_fgetc(FILE * input)
{
return (next_buffer_pos > 0) ? getc_buffer[--next_buffer_pos] : fgetc(input);
}
/* =============================== */
/* Pushes character back on input. */
/* =============================== */
int
my_ungetc(int c, FILE * input)
{
int rc;
if (next_buffer_pos >= GETC_BUFF_SIZE)
{
fprintf(stderr, "Error: cannot push back more than %d characters\n",
GETC_BUFF_SIZE);
rc = EOF;
}
else
{
rc = getc_buffer[next_buffer_pos++] = (unsigned char)c;
if (feof(input))
clearerr(input); /* No more EOF. */
}
return rc;
}
|
