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 tarball for details.
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 read is stored in it.
18 * Return NULL if EOF/error */
19 char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
26 while ((ch = getc(file)) != EOF) {
27 /* grow the line buffer as necessary */
28 if (idx >= linebufsz) {
30 linebuf = xrealloc(linebuf, linebufsz);
32 linebuf[idx++] = (char) ch;
33 if (!ch || (end && ch == '\n'))
39 // huh, does fgets discard prior data on error like this?
40 // I don't think so....
45 linebuf = xrealloc(linebuf, idx + 1);
51 /* Get line, including trailing \n if any */
52 char* FAST_FUNC xmalloc_fgets(FILE *file)
56 return bb_get_chunk_from_file(file, &i);
59 /* Get line. Remove trailing \n */
60 char* FAST_FUNC xmalloc_fgetline(FILE *file)
63 char *c = bb_get_chunk_from_file(file, &i);
65 if (i && c[--i] == '\n')
72 /* Faster routines (~twice as fast). +170 bytes. Unused as of 2008-07.
74 * NB: they stop at NUL byte too.
75 * Performance is important here. Think "grep 50gigabyte_file"...
76 * Ironically, grep can't use it because of NUL issue.
77 * We sorely need C lib to provide fgets which reports size!
80 * Actually, uclibc and glibc have it. man getline. It's GNUism,
81 * but very useful one (if it's as fast as this code).
83 * - currently, sed and sort use bb_get_chunk_from_file and heavily
84 * depend on its "stop on \n or \0" behavior, and STILL they fail
85 * to handle all cases with embedded NULs correctly. So:
86 * - audit sed and sort; convert them to getline FIRST.
87 * - THEN ditch bb_get_chunk_from_file, replace it with getline.
88 * - provide getline implementation for non-GNU systems.
91 static char* xmalloc_fgets_internal(FILE *file, int *sizep)
100 linebuf = xrealloc(linebuf, idx + 0x100);
101 r = fgets(&linebuf[idx], 0x100, file);
103 /* need to terminate in case this is error
104 * (EOF puts NUL itself) */
108 /* stupid. fgets knows the len, it should report it somehow */
109 len = strlen(&linebuf[idx]);
111 if (len != 0xff || linebuf[idx - 1] == '\n')
116 /* xrealloc(linebuf, idx + 1) is up to caller */
123 /* Get line, remove trailing \n */
124 char* FAST_FUNC xmalloc_fgetline_fast(FILE *file)
127 char *r = xmalloc_fgets_internal(file, &sz);
128 if (r && r[sz - 1] == '\n')
130 return r; /* not xrealloc(r, sz + 1)! */
133 char* FAST_FUNC xmalloc_fgets(FILE *file)
136 return xmalloc_fgets_internal(file, &sz);
139 /* Get line, remove trailing \n */
140 char* FAST_FUNC xmalloc_fgetline(FILE *file)
143 char *r = xmalloc_fgets_internal(file, &sz);
146 if (r[sz - 1] == '\n')
148 return xrealloc(r, sz + 1);