* Copyright (C) 2004 Erik Andersen <andersen@codepoet.org>
* Copyright (C) 2001 Matt Krai
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
#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 read is stored in it.
- * Return NULL if EOF/error */
char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
{
int ch;
- int idx = 0;
+ unsigned idx = 0;
char *linebuf = NULL;
- int linebufsz = 0;
while ((ch = getc(file)) != EOF) {
/* grow the line buffer as necessary */
- if (idx >= linebufsz) {
- linebufsz += 80;
- linebuf = xrealloc(linebuf, linebufsz);
- }
+ if (!(idx & 0xff))
+ linebuf = xrealloc(linebuf, idx + 0x100);
linebuf[idx++] = (char) ch;
- if (!ch || (end && ch == '\n'))
+ if (ch == '\0')
+ break;
+ if (end && ch == '\n')
break;
}
if (end)
return bb_get_chunk_from_file(file, &i);
}
-
/* Get line. Remove trailing \n */
char* FAST_FUNC xmalloc_fgetline(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)
+{
+ 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)
+{
+ 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;
+
+ 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;
+}
+
+/* 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);
+}
+
+/* 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