Module Name: src
Committed By: dsl
Date: Sat Oct 24 14:50:48 UTC 2009
Modified Files:
src/lib/libc/stdio: fgets.c
Log Message:
Check for EOF before erroring fgets() with length <= 0.
If length is invalid, set errno = EINVAL and __SERR as well returning NULL.
Should let me close PR/41992.
To generate a diff of this commit:
cvs rdiff -u -r1.23 -r1.24 src/lib/libc/stdio/fgets.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libc/stdio/fgets.c
diff -u src/lib/libc/stdio/fgets.c:1.23 src/lib/libc/stdio/fgets.c:1.24
--- src/lib/libc/stdio/fgets.c:1.23 Wed Oct 14 21:25:52 2009
+++ src/lib/libc/stdio/fgets.c Sat Oct 24 14:50:48 2009
@@ -1,4 +1,4 @@
-/* $NetBSD: fgets.c,v 1.23 2009/10/14 21:25:52 dsl Exp $ */
+/* $NetBSD: fgets.c,v 1.24 2009/10/24 14:50:48 dsl Exp $ */
/*-
* Copyright (c) 1990, 1993
@@ -37,12 +37,13 @@
#if 0
static char sccsid[] = "@(#)fgets.c 8.2 (Berkeley) 12/22/93";
#else
-__RCSID("$NetBSD: fgets.c,v 1.23 2009/10/14 21:25:52 dsl Exp $");
+__RCSID("$NetBSD: fgets.c,v 1.24 2009/10/24 14:50:48 dsl Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include <assert.h>
#include <stdio.h>
+#include <errno.h>
#include <string.h>
#include "reentrant.h"
#include "local.h"
@@ -61,14 +62,12 @@
int n;
FILE *fp;
{
- size_t len;
+ int len;
char *s;
unsigned char *p, *t;
_DIAGASSERT(buf != NULL);
_DIAGASSERT(fp != NULL);
- if (n <= 0) /* sanity check */
- return (NULL);
FLOCKFILE(fp);
_SET_ORIENTATION(fp, -1);
@@ -97,11 +96,25 @@
* newline, and stop. Otherwise, copy entire chunk
* and loop.
*/
- if (len > (size_t)n)
+ if (len > n) {
+ if (n < 0) {
+ /*
+ * Caller's length <= 0
+ * We can't write into the buffer, so cannot
+ * return a string, so must return NULL.
+ * Set errno and __SERR so it is consistent.
+ * TOG gives no indication of what to do here!
+ */
+ errno = EINVAL;
+ fp->_flags |= __SERR;
+ FUNLOCKFILE(fp);
+ return NULL;
+ }
len = n;
+ }
t = memchr((void *)p, '\n', len);
if (t != NULL) {
- len = ++t - p;
+ len = (int)(++t - p);
fp->_r -= len;
fp->_p = t;
(void)memcpy((void *)s, (void *)p, len);
