Clean up write_in_full() users
- From
Linus Torvalds <torvalds@osdl.org>
- Date
- Jan 12, 2007, 04:23 UTC
- Message-ID
- <Pine.LNX.4.64.0701112014050.3594@woody.osdl.org>
With the new-and-improved write_in_full() semantics, where a partial write simply always returns a real error (and always sets 'errno' when that happens, including for the disk full case), a lot of the callers of write_in_full() were just unnecessarily complex.
In particular, there's no reason to ever check for a zero length or return: if the length was zero, we'll return zero, otherwise, if a disk full resulted in the actual write() system call returning zero the write_in_full() logic would have correctly turned that into a negative return value, with 'errno' set to ENOSPC.
I really wish every "write_in_full()" user would just check against "<0" now, but this fixes the nasty and stupid ones.
Signed-off-by: Linus Torvalds <torvalds@osdl.org> ---
I actually think "read_in_full()" should get the same loving tender care too, for all the same reasons. I think "read_or_die()" is totally broken. Anybody who uses "read_or_die()" is buggy by definition, since it will do a partial read AND NOT RETURN ANY INDICATION THAT IT WAS PARTIAL!
Can I please ask people who do these idiotic cleanups to get their act together?
I'll send a patch for that next, but I looked at "write_in_full()" first, for historical reasons.
diff --git a/sha1_file.c b/sha1_file.c index 18dd89b..2a5be53 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -1618,14 +1618,7 @@ int move_temp_to_file(const char *tmpfile, const char *filename) static int write_buffer(int fd, const void *buf, size_t len) { - ssize_t size; - - if (!len) - return 0; - size = write_in_full(fd, buf, len); - if (!size) - return error("file write: disk full"); - if (size < 0) + if (write_in_full(fd, buf, len) < 0) return error("file write error (%s)", strerror(errno)); return 0; } diff --git a/write_or_die.c b/write_or_die.c index 488de72..1224cac 100644 --- a/write_or_die.c +++ b/write_or_die.c @@ -58,14 +58,7 @@ int write_in_full(int fd, const void *buf, size_t count) void write_or_die(int fd, const void *buf, size_t count) { - ssize_t written; - - if (!count) - return; - written = write_in_full(fd, buf, count); - if (written == 0) - die("disk full?"); - else if (written < 0) { + if (write_in_full(fd, buf, count) < 0) { if (errno == EPIPE) exit(0); die("write error (%s)", strerror(errno)); @@ -74,16 +67,7 @@ void write_or_die(int fd, const void *buf, size_t count) int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg) { - ssize_t written; - - if (!count) - return 1; - written = write_in_full(fd, buf, count); - if (written == 0) { - fprintf(stderr, "%s: disk full?\n", msg); - return 0; - } - else if (written < 0) { + if (write_in_full(fd, buf, count) < 0) { if (errno == EPIPE) exit(0); fprintf(stderr, "%s: write error (%s)\n", @@ -96,16 +80,7 @@ int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg) int write_or_whine(int fd, const void *buf, size_t count, const char *msg) { - ssize_t written; - - if (!count) - return 1; - written = write_in_full(fd, buf, count); - if (written == 0) { - fprintf(stderr, "%s: disk full?\n", msg); - return 0; - } - else if (written < 0) { + if (write_in_full(fd, buf, count) < 0) { fprintf(stderr, "%s: write error (%s)\n", msg, strerror(errno)); return 0;