Commit Graph

32 Commits

Author SHA1 Message Date
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 1e0c3a0ba6 whitespace fixes 2015-03-27 22:48:05 +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 4af8889396 Audit uniq(1)
Refactor the manpage and small style-changes in uniq.c.
Remove unnecessary "else", we catch argc > 2 earlier already.
2015-03-17 23:59:09 +01:00
Hiltjo Posthuma 78187474cf uniq: optimization: reuse the prevline buffer
don't strdup for each prevline, try to reuse the allocated buffer and if needed
increase it's size.
2015-03-08 14:50:46 +01:00
Hiltjo Posthuma b2e73936bf uniq: dont use count format if empty 2015-03-07 14:04:04 +01:00
Hiltjo Posthuma 695940d50c uniq: style put main at bottom 2015-03-07 14:02:04 +01:00
Hiltjo Posthuma 4092196fdc uniq: fix argv check
uniq inputfile failed with "extra argument"
2015-03-07 13:29:12 +01:00
Quentin Rameau 7ddaf1d6fe uniq: corrected arg syntax in usage() 2015-02-19 14:57:09 +00:00
FRIGN 31572c8b0e Clean up #includes 2015-02-14 21:12:23 +01:00
Tai Chi Minh Ralph Eastwood 70694a318c uniq: add support for writing output files 2015-02-11 15:26:57 +00:00
sin 17dad35015 uniq: Fix typo in usage 2015-02-11 12:50:39 +00:00
sin b2370171e6 uniq: Match usage with manpage 2015-02-11 12:21:31 +00:00
sin 5f06185b1b uniq: Fixup program usage and manpage
Remove -i as it is not required by POSIX.  We'll add it if we
hit scripts that require it.
2015-02-11 12:19:38 +00:00
sin 26bc079ecc uniq: Style fix 2015-02-11 12:02:33 +00:00
Tai Chi Minh Ralph Eastwood bc2310376f uniq: add ascii implementation of -f and -s flags 2015-02-11 10:56:58 +00:00
Evan Gates 84b08427a1 remove agetline 2014-11-18 21:05:28 +00:00
FRIGN e17b9cdd0a Convert codebase to use emalloc.c utility-functions
This also definitely increases readability and makes OOM-conditions
more consistent.
2014-11-16 10:22:39 +00:00
FRIGN 7fc5856e64 Tweak NULL-pointer checks
Use !p and p when comparing pointers as opposed to explicit
checks against NULL.  This is generally easier to read.
2014-11-14 10:54:30 +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 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 0c5b7b9155 Stop using EXIT_{SUCCESS,FAILURE} 2014-10-02 23:46:59 +01:00
Hiltjo Posthuma fab4b384e7 use agetline instead of agets
also use agetline where fgets with a static buffer was used previously.

Signed-off-by: Hiltjo Posthuma <hiltjo@codemadness.org>
2014-06-01 18:03:10 +01:00
Hiltjo Posthuma 953ebf3573 code style
Signed-off-by: Hiltjo Posthuma <hiltjo@codemadness.org>
2014-06-01 18:02:30 +01:00
sin cb005c150d Fix naming covention for uniq(1) 2014-01-20 10:49:28 +00:00
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
sin 83c2c3d1f5 Add 'not implemented' errors for unimplemented flags
These used to live in TODO but we got rid off them.  Make sure
we keep track of what we want to support by printing a message
when those flags are unimplemented.
2013-10-05 13:51:45 +01:00
stateless 7216a53a7e Remove unnecessary exit(1) in usage()
Signed-off-by: Christoph Lohmann <20h@r-36.net>
2013-06-19 19:58:19 +02:00
Christoph Lohmann 4d38f60685 Eliminating the getopt disgrace. 2013-06-14 20:20:47 +02:00
Christoph Lohmann 52d39e35c2 The style inquisition on basename. 2013-03-05 21:35:55 +01:00
Robert Ransom a16f603b20 uniq: Lobotomize for POSIX-subset compatibility
POSIX uniq(1) is required to write to its second argument,
if one is given.
The multiple-input feature I accidentally added might be useful,
but users and scripts who rely on it would be put at risk for data loss
if they ever run into a POSIX uniq(1).
2012-05-21 23:33:36 +00:00
Robert Ransom 85efaad43b uniq: Initial commit 2012-05-21 23:24:28 +00:00