Commit Graph

30 Commits

Author SHA1 Message Date
FRIGN
0545d32ce9 Handle '-' consistently
In general, POSIX does not define /dev/std{in, out, err} because it
does not want to depend on the dev-filesystem.
For utilities, it thus introduced the '-'-keyword to denote standard
input (and output in some cases) and the programs have to deal with
it accordingly.

Sadly, the design of many tools doesn't allow strict shell-redirections
and many scripts don't even use this feature when possible.

Thus, we made the decision to implement it consistently across all
tools where it makes sense (namely those which read files).

Along the way, I spotted some behavioural bugs in libutil/crypt.c and
others where it was forgotten to fshut the files after use.
2015-05-16 13:34:00 +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
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
edba90934d Small fix in head.c
Only deal with this newline-handling when many is true.
2015-03-06 00:32:22 +01:00
sin
68ccf5c0eb head: Fix usage and manpage
-N is not a flag but rather a number specification.  Be consistent
and use -num to be consistent with -n num.  num is properly highlighted
now as well.
2015-03-05 08:16:56 +00:00
FRIGN
38066de8c2 Audit head(1)
1) Use (s)size_t in head().
2) BUGFIX: only check buf[len - 1] when len > 0, else there would
   be an overflow when getline returns 0 (which can happen) and a
   very potential segmentation fault.
3) fix error-messages.
4) update usage().
5) argv-argc-style.
6) clear up the main loop with if (newline).
7) add newline before return.
2015-03-05 01:01:52 +01:00
FRIGN
31572c8b0e Clean up #includes 2015-02-14 21:12:23 +01:00
FRIGN
27b770c02c Adjust some limits to more flexibility for strtonum 2015-02-01 01:24:03 +01:00
sin
b66c44b24e ARGNUMF() only works on base 10 as it uses strtonum underneath 2015-01-30 16:45:44 +00:00
FRIGN
fd562481f3 Convert estrto{l, ul} to estrtonum
Enough with this insanity!
2015-01-30 16:52:44 +01:00
FRIGN
741d8c9a76 Add mandoc-manpage for head(1) and clean up code
and mark it as finished in the README.
2015-01-25 22:01:26 +01:00
sin
93c8aaf925 Print header in head(1) 2014-11-20 22:52:05 +00:00
sin
2a84dd5076 Respect exit status in head(1) 2014-11-20 22:39:56 +00:00
Evan Gates
84b08427a1 remove agetline 2014-11-18 21:05:28 +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
dwts
b700d5a8ed minor style changes 2014-04-22 13:46:19 +01:00
sin
b8edf3b4ee Add weprintf() and replace fprintf(stderr, ...) calls
There is still some programs left to be updated for this.

Many of these programs would stop on the first file that they
could not open.
2013-11-13 11:41:43 +00:00
sin
d9abff1e84 Don't exit on the first file that can't be opened for head and fold 2013-11-12 10:46:53 +00:00
dsp
3f9e501f6b Add ARGNUM and ARGNUMF(base)
This is useful to support the obsolete syntax -NUM for tools like
head, tail and fold.
2013-11-12 10:17:52 +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
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
Connor Lane Smith
954106050f rename estrtol 2011-06-10 14:55:01 +01:00
Connor Lane Smith
7c251bcd4f refactor strnum 2011-06-10 05:41:40 +01:00
Connor Lane Smith
d6a9e35d0b really long lines 2011-05-25 20:40:47 +01:00
Connor Lane Smith
47308190b3 update manpages 2011-05-25 18:29:46 +01:00
Connor Lane Smith
262f357fdd add head 2011-05-25 11:42:17 +01:00