1 /* vi: set sw=4 ts=4: */
5 * Copyright (C) 2005, 2006 Rob Landley <rob@landley.net>
6 * Copyright (C) 2004 Erik Andersen <andersen@codepoet.org>
7 * Copyright (C) 2001 Matt Krai
9 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
14 /* This function reads an entire line from a text file, up to a newline
15 * or NUL byte, inclusive. It returns a malloc'ed char * which
16 * must be free'ed by the caller. If end is NULL '\n' isn't considered
17 * end of line. If end isn't NULL, length of the chunk is stored in it.
18 * If lineno is not NULL, *lineno is incremented for each line,
19 * and also trailing '\' is recognized as line continuation.
21 * Returns NULL if EOF/error. */
22 char* FAST_FUNC bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno)
29 while ((ch = getc(file)) != EOF) {
30 /* grow the line buffer as necessary */
31 if (idx >= linebufsz) {
33 linebuf = xrealloc(linebuf, linebufsz);
35 linebuf[idx++] = (char) ch;
38 if (end && ch == '\n') {
42 if (idx < 2 || linebuf[idx-2] != '\\')
49 /* handle corner case when the file is not ended with '\n' */
50 if (ch == EOF && lineno != NULL)
54 // huh, does fgets discard prior data on error like this?
55 // I don't think so....
60 linebuf = xrealloc(linebuf, idx + 1);
66 char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
68 return bb_get_chunk_with_continuation(file, end, NULL);
71 /* Get line, including trailing \n if any */
72 char* FAST_FUNC xmalloc_fgets(FILE *file)
76 return bb_get_chunk_from_file(file, &i);
78 /* Get line. Remove trailing \n */
79 char* FAST_FUNC xmalloc_fgetline(FILE *file)
82 char *c = bb_get_chunk_from_file(file, &i);
84 if (i && c[--i] == '\n')
91 /* GNUism getline() should be faster (not tested) than a loop with fgetc */
93 /* Get line, including trailing \n if any */
94 char* FAST_FUNC xmalloc_fgets(FILE *file)
99 if (getline(&res_buf, &res_sz, file) == -1) {
100 free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */
103 //TODO: trimming to res_sz?
106 /* Get line. Remove trailing \n */
107 char* FAST_FUNC xmalloc_fgetline(FILE *file)
109 char *res_buf = NULL;
112 res_sz = getline(&res_buf, &res_sz, file);
114 if ((ssize_t)res_sz != -1) {
115 if (res_buf[res_sz - 1] == '\n')
116 res_buf[--res_sz] = '\0';
117 //TODO: trimming to res_sz?
119 free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */
128 /* Faster routines (~twice as fast). +170 bytes. Unused as of 2008-07.
130 * NB: they stop at NUL byte too.
131 * Performance is important here. Think "grep 50gigabyte_file"...
132 * Ironically, grep can't use it because of NUL issue.
133 * We sorely need C lib to provide fgets which reports size!
136 * Actually, uclibc and glibc have it. man getline. It's GNUism,
137 * but very useful one (if it's as fast as this code).
139 * - currently, sed and sort use bb_get_chunk_from_file and heavily
140 * depend on its "stop on \n or \0" behavior, and STILL they fail
141 * to handle all cases with embedded NULs correctly. So:
142 * - audit sed and sort; convert them to getline FIRST.
143 * - THEN ditch bb_get_chunk_from_file, replace it with getline.
144 * - provide getline implementation for non-GNU systems.
147 static char* xmalloc_fgets_internal(FILE *file, int *sizep)
151 char *linebuf = NULL;
156 linebuf = xrealloc(linebuf, idx + 0x100);
157 r = fgets(&linebuf[idx], 0x100, file);
159 /* need to terminate in case this is error
160 * (EOF puts NUL itself) */
164 /* stupid. fgets knows the len, it should report it somehow */
165 len = strlen(&linebuf[idx]);
167 if (len != 0xff || linebuf[idx - 1] == '\n')
172 /* xrealloc(linebuf, idx + 1) is up to caller */
179 /* Get line, remove trailing \n */
180 char* FAST_FUNC xmalloc_fgetline_fast(FILE *file)
183 char *r = xmalloc_fgets_internal(file, &sz);
184 if (r && r[sz - 1] == '\n')
186 return r; /* not xrealloc(r, sz + 1)! */
189 char* FAST_FUNC xmalloc_fgets(FILE *file)
192 return xmalloc_fgets_internal(file, &sz);
195 /* Get line, remove trailing \n */
196 char* FAST_FUNC xmalloc_fgetline(FILE *file)
199 char *r = xmalloc_fgets_internal(file, &sz);
202 if (r[sz - 1] == '\n')
204 return xrealloc(r, sz + 1);