optimize config_read() (by Timo Teras <timo.teras AT iki.fi>)
function old new delta
bb_get_chunk_with_continuation - 176 +176
find_pair 169 187 +18
...
process_stdin 443 433 -10
config_read 549 456 -93
bb_get_chunk_from_file 139 7 -132
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 7/7 up/down: 215/-254) Total: -39 bytes
diff --git a/libbb/get_line_from_file.c b/libbb/get_line_from_file.c
index 968d757..3cb46d2 100644
--- a/libbb/get_line_from_file.c
+++ b/libbb/get_line_from_file.c
@@ -9,18 +9,22 @@
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
-/* for getline() [GNUism] */
+/* 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 read is stored in it.
- * Return NULL if EOF/error */
-char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end)
+ * 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;
@@ -30,12 +34,20 @@
while ((ch = getc(file)) != EOF) {
/* grow the line buffer as necessary */
if (idx >= linebufsz) {
- linebufsz += 80;
+ linebufsz += 256;
linebuf = xrealloc(linebuf, linebufsz);
}
linebuf[idx++] = (char) ch;
- if (!ch || (end && ch == '\n'))
+ 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;
@@ -52,6 +64,11 @@
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)
{
@@ -72,7 +89,6 @@
}
#if 0
-
/* GNUism getline() should be faster (not tested) than a loop with fgetc */
/* Get line, including trailing \n if any */