From 0a1f910d396bf47c3adf1608f16805eafce1c69c Mon Sep 17 00:00:00 2001 From: ngie Date: Sun, 11 Jan 2015 19:15:28 +0000 Subject: MFC discussed with: jilles, -developers MFC r266971: - Return NULL and set errno to EINVAL if size is 0 (as required by POSIX). Update the manpage to reflect this change. - Always set the current position to the first null-byte when opening in append mode. This makes the implementation compatible with glibc's. Update the test suite. Reported by: pho Approved by: cognet --- lib/libc/stdio/fmemopen.c | 17 +++++++++-------- lib/libc/stdio/fopen.3 | 9 +++++++++ 2 files changed, 18 insertions(+), 8 deletions(-) (limited to 'lib/libc/stdio') diff --git a/lib/libc/stdio/fmemopen.c b/lib/libc/stdio/fmemopen.c index 581a91e..ebd3596 100644 --- a/lib/libc/stdio/fmemopen.c +++ b/lib/libc/stdio/fmemopen.c @@ -57,6 +57,14 @@ fmemopen(void * __restrict buf, size_t size, const char * __restrict mode) int flags, rc; /* + * POSIX says we shall return EINVAL if size is 0. + */ + if (size == 0) { + errno = EINVAL; + return (NULL); + } + + /* * Retrieve the flags as used by open(2) from the mode argument, and * validate them. */ @@ -119,14 +127,7 @@ fmemopen(void * __restrict buf, size_t size, const char * __restrict mode) */ switch (mode[0]) { case 'a': - if (ck->bin) { - /* - * This isn't useful, since the buffer isn't allowed - * to grow. - */ - ck->off = ck->len = size; - } else - ck->off = ck->len = strnlen(ck->buf, ck->size); + ck->off = ck->len = strnlen(ck->buf, ck->size); break; case 'r': ck->len = size; diff --git a/lib/libc/stdio/fopen.3 b/lib/libc/stdio/fopen.3 index f11f4e0..b39cb5a 100644 --- a/lib/libc/stdio/fopen.3 +++ b/lib/libc/stdio/fopen.3 @@ -302,6 +302,15 @@ for any of the errors specified for the routines .Xr fclose 3 and .Xr fflush 3 . +.Pp +The +.Fn fmemopen +function +may also fail and set +.Va errno +if the +.Fa size +argument is 0. .Sh SEE ALSO .Xr open 2 , .Xr fclose 3 , -- cgit v1.1