procps/lib/fileutils.c
Jim Warner ce5e995921 library: for atexit() support, fix fileutils for EPIPE
When fileutils with stream error checking was borrowed
from GNU lib, an omission was also propagated where an
errno of EPIPE wouldn't be preserved in close_stream()
making a test for EPIPE in close_stdout() meaningless.

This patch corrects such oversight so that an errno of
EPIPE no longer produces 'write error' at program end.

( gnulib provides for optionally ignoring EPIPE, but )
( if a program chooses to ignore it, then their code )
( appears to suffer from this close_stream oversight )

Reference(s):
. original fileutilis addition
commit c7cf98b0e0
. bugzilla report
https://bugzilla.redhat.com/show_bug.cgi?id=976199
2013-06-26 17:58:56 +02:00

56 lines
1.2 KiB
C

#include <errno.h>
#ifdef HAVE_ERROR_H
# include <error.h>
#endif
#ifdef HAVE_STDIO_EXT_H
# include <stdio_ext.h>
#else
/* FIXME: use a more portable definition of __fpending() (from gnulib?) */
# include <stdio.h>
# define __fpending(fp) ((fp)->_p - (fp)->_bf._base)
#endif
#include <stdlib.h>
#include <unistd.h>
#include "nls.h"
#include "fileutils.h"
#ifndef HAVE_ERROR_H
# include "c.h" /* for error() emulation */
#endif
int close_stream(FILE * stream)
{
const int some_pending = (__fpending(stream) != 0);
const int prev_fail = (ferror(stream) != 0);
const int fclose_fail = (fclose(stream) != 0);
if (prev_fail || (fclose_fail && (some_pending || errno != EBADF))) {
if (!fclose_fail && errno != EPIPE)
errno = 0;
return EOF;
}
return 0;
}
/* Use atexit(); */
void close_stdout(void)
{
if (close_stream(stdout) != 0 && !(errno == EPIPE)) {
char const *write_error = _("write error");
error(0, errno, "%s", write_error);
_exit(EXIT_FAILURE);
}
if (close_stream(stderr) != 0)
_exit(EXIT_FAILURE);
}
#ifdef TEST_PROGRAM
#include <stdio.h>
int main(int argc, char *argv[])
{
atexit(close_stdout);
printf("Hello, World!\n");
return EXIT_SUCCESS;
}
#endif /* TEST_PROGRAM */