1 /* vi: set sw=4 ts=4: */
2 /*
3 * Utility routines.
4 *
5 * Copyright (C) many different people.
6 * If you wrote this, please acknowledge your work.
7 *
8 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
9 */
10
11 #include "libbb.h"
12
xmalloc_fgets_internal(FILE * file,const char * terminating_string,int chop_off,size_t * maxsz_p)13 static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, int chop_off, size_t *maxsz_p)
14 {
15 char *linebuf = NULL;
16 const int term_length = strlen(terminating_string);
17 int end_string_offset;
18 int linebufsz = 0;
19 int idx = 0;
20 int ch;
21 size_t maxsz = *maxsz_p;
22
23 while (1) {
24 ch = fgetc(file);
25 if (ch == EOF) {
26 if (idx == 0)
27 return linebuf; /* NULL */
28 break;
29 }
30
31 if (idx >= linebufsz) {
32 linebufsz += 200;
33 linebuf = xrealloc(linebuf, linebufsz);
34 if (idx >= maxsz) {
35 linebuf[idx] = ch;
36 idx++;
37 break;
38 }
39 }
40
41 linebuf[idx] = ch;
42 idx++;
43
44 /* Check for terminating string */
45 end_string_offset = idx - term_length;
46 if (end_string_offset >= 0
47 && memcmp(&linebuf[end_string_offset], terminating_string, term_length) == 0
48 ) {
49 if (chop_off)
50 idx -= term_length;
51 break;
52 }
53 }
54 /* Grow/shrink *first*, then store NUL */
55 linebuf = xrealloc(linebuf, idx + 1);
56 linebuf[idx] = '\0';
57 *maxsz_p = idx;
58 return linebuf;
59 }
60
61 /* Read up to TERMINATING_STRING from FILE and return it,
62 * including terminating string.
63 * Non-terminated string can be returned if EOF is reached.
64 * Return NULL if EOF is reached immediately. */
xmalloc_fgets_str(FILE * file,const char * terminating_string)65 char* FAST_FUNC xmalloc_fgets_str(FILE *file, const char *terminating_string)
66 {
67 size_t maxsz = INT_MAX - 4095;
68 return xmalloc_fgets_internal(file, terminating_string, 0, &maxsz);
69 }
70
xmalloc_fgets_str_len(FILE * file,const char * terminating_string,size_t * maxsz_p)71 char* FAST_FUNC xmalloc_fgets_str_len(FILE *file, const char *terminating_string, size_t *maxsz_p)
72 {
73 size_t maxsz;
74
75 if (!maxsz_p) {
76 maxsz = INT_MAX - 4095;
77 maxsz_p = &maxsz;
78 }
79 return xmalloc_fgets_internal(file, terminating_string, 0, maxsz_p);
80 }
81
xmalloc_fgetline_str(FILE * file,const char * terminating_string)82 char* FAST_FUNC xmalloc_fgetline_str(FILE *file, const char *terminating_string)
83 {
84 size_t maxsz = INT_MAX - 4095;
85 return xmalloc_fgets_internal(file, terminating_string, 1, &maxsz);
86 }
87