/*
* Utility routines.
*
- * Copyright (C) many different people.
- * If you wrote this, please acknowledge your work.
+ * Copyright (C) 2005, 2006 Rob Landley <rob@landley.net>
+ * Copyright (C) 2004 Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2001 Matt Krai
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
-
-#include <stdio.h>
-#include <stdlib.h>
#include "libbb.h"
-/* get_line_from_file() - This function reads an entire line from a text file,
- * up to a newline. It returns a malloc'ed char * which must be stored and
- * free'ed by the caller. If 'c' is nonzero, the trailing '\n' (if any)
- * is removed. In event of a read error or EOF, NULL is returned. */
-
-static char *private_get_line_from_file(FILE *file, int c)
+char* FAST_FUNC bb_get_chunk_from_file(FILE *file, size_t *end)
{
-#define GROWBY (80) /* how large we will grow strings by */
-
int ch;
- int idx = 0;
+ size_t idx = 0;
char *linebuf = NULL;
- int linebufsz = 0;
while ((ch = getc(file)) != EOF) {
/* grow the line buffer as necessary */
- if (idx > linebufsz - 2) {
- linebuf = xrealloc(linebuf, linebufsz += GROWBY);
+ if (!(idx & 0xff)) {
+ if (idx == ((size_t)-1) - 0xff)
+ bb_die_memory_exhausted();
+ linebuf = xrealloc(linebuf, idx + 0x100);
}
- linebuf[idx++] = (char)ch;
- if (!ch) return linebuf;
- if (c<2 && ch == '\n') {
- if (c) {
- --idx;
- }
+ linebuf[idx++] = (char) ch;
+ if (ch == '\0')
+ break;
+ if (end && ch == '\n')
break;
- }
}
+ if (end)
+ *end = idx;
if (linebuf) {
- if (ferror(file)) {
- free(linebuf);
- return NULL;
- }
- linebuf[idx] = 0;
+ // huh, does fgets discard prior data on error like this?
+ // I don't think so....
+ //if (ferror(file)) {
+ // free(linebuf);
+ // return NULL;
+ //}
+ linebuf = xrealloc(linebuf, idx + 1);
+ linebuf[idx] = '\0';
}
return linebuf;
}
-extern char *bb_get_line_from_file(FILE *file)
+/* Get line, including trailing \n if any */
+char* FAST_FUNC xmalloc_fgets(FILE *file)
+{
+ size_t i;
+
+ return bb_get_chunk_from_file(file, &i);
+}
+/* Get line. Remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline(FILE *file)
+{
+ size_t i;
+ char *c = bb_get_chunk_from_file(file, &i);
+
+ if (i && c[--i] == '\n')
+ c[i] = '\0';
+
+ return c;
+}
+
+#if 0
+/* GNUism getline() should be faster (not tested) than a loop with fgetc */
+
+/* Get line, including trailing \n if any */
+char* FAST_FUNC xmalloc_fgets(FILE *file)
+{
+ char *res_buf = NULL;
+ size_t res_sz;
+
+ if (getline(&res_buf, &res_sz, file) == -1) {
+ free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */
+ res_buf = NULL;
+ }
+//TODO: trimming to res_sz?
+ return res_buf;
+}
+/* Get line. Remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline(FILE *file)
{
- return private_get_line_from_file(file, 0);
+ char *res_buf = NULL;
+ size_t res_sz;
+
+ res_sz = getline(&res_buf, &res_sz, file);
+
+ if ((ssize_t)res_sz != -1) {
+ if (res_buf[res_sz - 1] == '\n')
+ res_buf[--res_sz] = '\0';
+//TODO: trimming to res_sz?
+ } else {
+ free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */
+ res_buf = NULL;
+ }
+ return res_buf;
}
-extern char *bb_get_chomped_line_from_file(FILE *file)
+#endif
+
+#if 0
+/* Faster routines (~twice as fast). +170 bytes. Unused as of 2008-07.
+ *
+ * NB: they stop at NUL byte too.
+ * Performance is important here. Think "grep 50gigabyte_file"...
+ * Ironically, grep can't use it because of NUL issue.
+ * We sorely need C lib to provide fgets which reports size!
+ *
+ * Update:
+ * Actually, uclibc and glibc have it. man getline. It's GNUism,
+ * but very useful one (if it's as fast as this code).
+ * TODO:
+ * - currently, sed and sort use bb_get_chunk_from_file and heavily
+ * depend on its "stop on \n or \0" behavior, and STILL they fail
+ * to handle all cases with embedded NULs correctly. So:
+ * - audit sed and sort; convert them to getline FIRST.
+ * - THEN ditch bb_get_chunk_from_file, replace it with getline.
+ * - provide getline implementation for non-GNU systems.
+ */
+
+static char* xmalloc_fgets_internal(FILE *file, int *sizep)
{
- return private_get_line_from_file(file, 1);
+ int len;
+ int idx = 0;
+ char *linebuf = NULL;
+
+ while (1) {
+ char *r;
+
+ linebuf = xrealloc(linebuf, idx + 0x100);
+ r = fgets(&linebuf[idx], 0x100, file);
+ if (!r) {
+ /* need to terminate in case this is error
+ * (EOF puts NUL itself) */
+ linebuf[idx] = '\0';
+ break;
+ }
+ /* stupid. fgets knows the len, it should report it somehow */
+ len = strlen(&linebuf[idx]);
+ idx += len;
+ if (len != 0xff || linebuf[idx - 1] == '\n')
+ break;
+ }
+ *sizep = idx;
+ if (idx) {
+ /* xrealloc(linebuf, idx + 1) is up to caller */
+ return linebuf;
+ }
+ free(linebuf);
+ return NULL;
}
-extern char *bb_get_chunk_from_file(FILE *file)
+/* Get line, remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline_fast(FILE *file)
{
- return private_get_line_from_file(file, 2);
+ int sz;
+ char *r = xmalloc_fgets_internal(file, &sz);
+ if (r && r[sz - 1] == '\n')
+ r[--sz] = '\0';
+ return r; /* not xrealloc(r, sz + 1)! */
}
+char* FAST_FUNC xmalloc_fgets(FILE *file)
+{
+ int sz;
+ return xmalloc_fgets_internal(file, &sz);
+}
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+/* Get line, remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline(FILE *file)
+{
+ int sz;
+ char *r = xmalloc_fgets_internal(file, &sz);
+ if (!r)
+ return r;
+ if (r[sz - 1] == '\n')
+ r[--sz] = '\0';
+ return xrealloc(r, sz + 1);
+}
+#endif
projects / oweals / busybox.git / blobdiff