Commit Graph

22 Commits

Author SHA1 Message Date
FRIGN d23cc72490 Simplify return & fshut() logic
Get rid of the !!()-constructs and use ret where available (or introduce it).

In some cases, there would be an "abort" on the first fshut-error, but we want
to close all files and report all warnings and then quit, not just the warning
for the first file.
2015-05-26 16:41:43 +01:00
FRIGN 9a074144c9 Remove handrolled strcmp()'s
Favor readability over bare-metal.
2015-05-21 15:43:38 +01:00
FRIGN 11e2d472bf Add *fshut() functions to properly flush file streams
This has been a known issue for a long time. Example:

printf "word" > /dev/full

wouldn't report there's not enough space on the device.
This is due to the fact that every libc has internal buffers
for stdout which store fragments of written data until they reach
a certain size or on some callback to flush them all at once to the
kernel.
You can force the libc to flush them with fflush(). In case flushing
fails, you can check the return value of fflush() and report an error.

However, previously, sbase didn't have such checks and without fflush(),
the libc silently flushes the buffers on exit without checking the errors.
No offense, but there's no way for the libc to report errors in the exit-
condition.

GNU coreutils solve this by having onexit-callbacks to handle the flushing
and report issues, but they have obvious deficiencies.
After long discussions on IRC, we came to the conclusion that checking the
return value of every io-function would be a bit too much, and having a
general-purpose fclose-wrapper would be the best way to go.

It turned out that fclose() alone is not enough to detect errors. The right
way to do it is to fflush() + check ferror on the fp and then to a fclose().
This is what fshut does and that's how it's done before each return.
The return value is obviously affected, reporting an error in case a flush
or close failed, but also when reading failed for some reason, the error-
state is caught.

the !!( ... + ...) construction is used to call all functions inside the
brackets and not "terminating" on the first.
We want errors to be reported, but there's no reason to stop flushing buffers
when one other file buffer has issues.
Obviously, functionales come before the flush and ret-logic comes after to
prevent early exits as well without reporting warnings if there are any.

One more advantage of fshut() is that it is even able to report errors
on obscure NFS-setups which the other coreutils are unable to detect,
because they only check the return-value of fflush() and fclose(),
not ferror() as well.
2015-04-05 09:13:56 +01:00
Hiltjo Posthuma a9bedca038 fix some signed/unsigned warnings and style fixes 2015-03-27 22:48:05 +01:00
Hiltjo Posthuma 44298e54e6 comm: minor optimization 2015-03-27 15:53:46 +01:00
FRIGN 9144d51594 Check getline()-return-values properly
It's not useful when 0 is returned anyway, so be sure that we have a
string with length > 0, this also solves some indexing-gotchas like
"len - 1" and so on.
Also, add checked getline()'s whenever it has been forgotten and
clean up the error-messages.
2015-03-27 14:49:48 +01:00
FRIGN a4587b84f8 Audit comm(1)
1) Use the LIMIT()-macro in util.h instead of defining our own.
2) Drop nextline() and finish(), not needed anymore. Use
   fputs in printline instead of printf.
   --> BUGFIX: Finish exited with status 1, but actually should
               exit with status 0 if ferror(f) == 0.
3) Don't use /dev/fd/0 and use idiomatic <stdin> and fp = stdin
   instead.
4) Refactor loop to use getline() instead of some handrolled
   nextline-function.
   --> BUGFIX: Line-length was limited to LINE_MAX before, now
               it's factually unlimited.
5) Combine diff >= 0 and diff <= 0 into one loop with a beginning
   continue-condition (diff && i == (diff < 0)).
6) BUGFIX: If diff == 0, don't print one buffer after EOFing on the
           other.
2015-03-11 13:47:08 +01:00
FRIGN 31572c8b0e Clean up #includes 2015-02-14 21:12:23 +01:00
FRIGN f9a1e11661 Add mandoc-manpage for comm(1) and clean up code
and mark it as finished in README.
2015-01-17 23:10:07 +00:00
sin 4399f35448 Fix two more instances where the check for "-" is insufficient 2014-11-18 21:58:50 +00:00
sin af8e38f5fa Fix some error messages
There's many more to go.
2014-11-17 16:22:01 +00:00
FRIGN ec8246bbc6 Un-boolify sbase
It actually makes the binaries smaller, the code easier to read
(gems like "val == true", "val == false" are gone) and actually
predictable in the sense of that we actually know what we're
working with (one bitwise operator was quite adventurous and
should now be fixed).

This is also more consistent with the other suckless projects
around which don't use boolean types.
2014-11-14 10:54:20 +00:00
FRIGN 7d2683ddf2 Sort includes and more cleanup and fixes in util/ 2014-11-14 10:54:10 +00:00
FRIGN eee98ed3a4 Fix coding style
It was about damn time. Consistency is very important in such a
big codebase.
2014-11-13 18:08:43 +00:00
sin 519a4f8105 Don't overwrite the line buffer when we hit EOF on one of the files in comm(1) 2014-11-13 16:01:53 +00:00
sin d208659414 Add "-" support to comm(1) 2014-11-13 16:01:44 +00:00
sin 0c5b7b9155 Stop using EXIT_{SUCCESS,FAILURE} 2014-10-02 23:46:59 +01:00
Hiltjo Posthuma 953ebf3573 code style
Signed-off-by: Hiltjo Posthuma <hiltjo@codemadness.org>
2014-06-01 18:02:30 +01:00
sin fbf71521f1 Rename variable `dif' to `diff' in comm(1) 2014-04-04 11:06:30 +01:00
sin b5a511dacf Exit with EXIT_SUCCESS/EXIT_FAILURE instead of 0 and 1
Fixed for consistency purposes.
2013-10-07 16:44:22 +01:00
Christoph Lohmann 7f88cf7021 Optimizing comm(1) with the second sent in patch. 2013-06-19 21:09:50 +02:00
stateless 12116cccc4 Add comm
Signed-off-by: Christoph Lohmann <20h@r-36.net>
2013-06-19 20:00:10 +02:00