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author | ngie <ngie@FreeBSD.org> | 2015-01-11 19:15:28 +0000 |
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committer | ngie <ngie@FreeBSD.org> | 2015-01-11 19:15:28 +0000 |
commit | 0a1f910d396bf47c3adf1608f16805eafce1c69c (patch) | |
tree | a6ea4260d0fa3a951d8063b29c894d9134fb675b | |
parent | addcd434f9cfc53268eb0ba8220e61e410a48727 (diff) | |
download | FreeBSD-src-0a1f910d396bf47c3adf1608f16805eafce1c69c.zip FreeBSD-src-0a1f910d396bf47c3adf1608f16805eafce1c69c.tar.gz |
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
-rw-r--r-- | lib/libc/stdio/fmemopen.c | 17 | ||||
-rw-r--r-- | lib/libc/stdio/fopen.3 | 9 | ||||
-rw-r--r-- | tools/regression/lib/libc/stdio/test-fmemopen.c | 47 |
3 files changed, 65 insertions, 8 deletions
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 , diff --git a/tools/regression/lib/libc/stdio/test-fmemopen.c b/tools/regression/lib/libc/stdio/test-fmemopen.c index 2788279..469cc1a 100644 --- a/tools/regression/lib/libc/stdio/test-fmemopen.c +++ b/tools/regression/lib/libc/stdio/test-fmemopen.c @@ -138,6 +138,13 @@ test_autoalloc() /* Close the FILE *. */ rc = fclose(fp); assert(rc == 0); + + /* Open a FILE * using a wrong mode */ + fp = fmemopen(NULL, 512, "r"); + assert(fp == NULL); + + fp = fmemopen(NULL, 512, "w"); + assert(fp == NULL); } void @@ -241,6 +248,44 @@ test_binary() assert(rc == 0); } +void +test_append_binary_pos() +{ + /* + * For compatibility with other implementations (glibc), we set the + * position to 0 when opening an automatically allocated binary stream + * for appending. + */ + + FILE *fp; + + fp = fmemopen(NULL, 16, "ab+"); + assert(ftell(fp) == 0L); + fclose(fp); + + /* + * Make sure that a pre-allocated buffer behaves correctly. + */ + char buf[] = "Hello"; + fp = fmemopen(buf, sizeof(buf), "ab+"); + assert(ftell(fp) == 5); + fclose(fp); +} + +void +test_size_0() +{ + /* + * POSIX mandates that we return EINVAL if size is 0 + */ + + FILE *fp; + + fp = fmemopen(NULL, 0, "r+"); + assert(fp == NULL); + assert(errno == EINVAL); +} + int main(void) { @@ -248,5 +293,7 @@ main(void) test_preexisting(); test_data_length(); test_binary(); + test_append_binary_pos(); + test_size_0(); return (0); } |