Commit Graph

14 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
FRIGN 9b06720f62 Refactor cryptcheck() to allow multiple list-files and stdin
Previously, it was not possible to use

sha1sum test.c | sha1sum -c

because the program would not differenciate between an empty
argument and a non-specified argument.
Moreover, why not allow this?

sha1sum -c hashlist1 hashlist2

Digging deeper I found that using function pointers and a
modification in the crypt-backend might simplify the program
a lot by passing the argument-list to both cryptmain and
cryptcheck.
Allowing more than one list-file to be specified is also
consistent with what the other implementations support,
so we not only have simpler code, we also do not silently
break if there's a script around passing multiple files to
check.
2015-03-01 22:51:52 +01:00
FRIGN e77f0b0b9f Simplify sha*sum.c 2015-02-17 10:08:28 +01:00
FRIGN 31572c8b0e Clean up #includes 2015-02-14 21:12:23 +01:00
sin 90507652c0 Staticise globals 2014-11-17 13:39:11 +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
Daniel Bainton c323f6f233 Support reading checksums from stdin 2014-05-05 10:05:48 +01:00
Daniel Bainton 9ad5ca5a15 Add breaks to the sha*sum arg cases 2014-05-05 10:05:43 +01:00
Hiltjo Posthuma 04f32f4d9a checksum tools: implement -c
Signed-off-by: Hiltjo Posthuma <hiltjo@codemadness.org>
2014-03-23 18:02:39 +00:00
sin 573d1954b2 Add cryptmain() and factor out the code from the crypt tools 2013-10-05 13:51:45 +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
sin 9e5718282a Add sha512sum(1) 2013-08-04 11:00:34 -04:00