/*
* 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 tarball for details.
*/
-#include <stdio.h>
+/* for getline() [GNUism]
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+*/
#include "libbb.h"
+/* This function reads an entire line from a text file, up to a newline
+ * or NUL byte, inclusive. It returns a malloc'ed char * which
+ * must be free'ed by the caller. If end is NULL '\n' isn't considered
+ * end of line. If end isn't NULL, length of the chunk is stored in it.
+ * If lineno is not NULL, *lineno is incremented for each line,
+ * and also trailing '\' is recognized as line continuation.
+ *
+ * Returns NULL if EOF/error. */
+char* FAST_FUNC bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno)
+{
+ int ch;
+ int idx = 0;
+ char *linebuf = NULL;
+ int linebufsz = 0;
+
+ while ((ch = getc(file)) != EOF) {
+ /* grow the line buffer as necessary */
+ if (idx >= linebufsz) {
+ linebufsz += 256;
+ linebuf = xrealloc(linebuf, linebufsz);
+ }
+ linebuf[idx++] = (char) ch;
+ if (!ch)
+ break;
+ if (end && ch == '\n') {
+ if (lineno == NULL)
+ break;
+ (*lineno)++;
+ if (idx < 2 || linebuf[idx-2] != '\\')
+ break;
+ idx -= 2;
+ }
+ }
+ if (end)
+ *end = idx;
+ if (linebuf) {
+ // 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;
+}
+
+char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
+{
+ return bb_get_chunk_with_continuation(file, end, NULL);
+}
+
+/* Get line, including trailing \n if any */
+char* FAST_FUNC xmalloc_fgets(FILE *file)
+{
+ int i;
+
+ return bb_get_chunk_from_file(file, &i);
+}
+/* Get line. Remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline(FILE *file)
+{
+ int i;
+ char *c = bb_get_chunk_from_file(file, &i);
+ if (i && c[--i] == '\n')
+ c[i] = '\0';
-/* 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. */
-extern char *get_line_from_file(FILE *file)
+ 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)
{
- static const int GROWBY = 80; /* how large we will grow strings by */
+ char *res_buf = NULL;
+ size_t res_sz;
- int ch;
+ 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)
+{
+ 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;
+}
+
+#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)
+{
+ int len;
int idx = 0;
char *linebuf = NULL;
- int linebufsz = 0;
while (1) {
- ch = fgetc(file);
- if (ch == EOF)
+ 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;
- /* grow the line buffer as necessary */
- while (idx > linebufsz-2)
- linebuf = xrealloc(linebuf, linebufsz += GROWBY);
- linebuf[idx++] = (char)ch;
- if (ch == '\n' || ch == '\0')
+ }
+ /* 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;
+}
- if (idx == 0)
- return NULL;
-
- linebuf[idx] = 0;
- return linebuf;
+/* Get line, remove trailing \n */
+char* FAST_FUNC xmalloc_fgetline_fast(FILE *file)
+{
+ 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