/* closeout.c - close standard output
- Copyright (C) 1998 Free Software Foundation, Inc.
+ Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
# define _(Text) Text
#endif
-#ifdef HAVE_STDLIB_H
+#if HAVE_STDLIB_H
# include <stdlib.h>
#endif
#ifndef EXIT_FAILURE
# define EXIT_FAILURE 1
#endif
+#include <stdio.h>
+
#include <errno.h>
#ifndef errno
extern int errno;
#endif
-#include <stdio.h>
#include "closeout.h"
#include "error.h"
+#include "quotearg.h"
+#include "__fpending.h"
+
+static int default_exit_status = EXIT_FAILURE;
+static const char *file_name;
+
+/* Set the value to be used for the exit status when close_stdout is called.
+ This is useful when it is not convenient to call close_stdout_status,
+ e.g., when close_stdout is called via atexit. */
+void
+close_stdout_set_status (int status)
+{
+ default_exit_status = status;
+}
+
+/* Set the file name to be reported in the event an error is detected
+ by close_stdout_status. */
+void
+close_stdout_set_file_name (const char *file)
+{
+ file_name = file;
+}
+
+/* Close standard output, exiting with status STATUS on failure.
+ If a program writes *anything* to stdout, that program should `fflush'
+ stdout and make sure that it succeeds before exiting. Otherwise,
+ suppose that you go to the extreme of checking the return status
+ of every function that does an explicit write to stdout. The last
+ printf can succeed in writing to the internal stream buffer, and yet
+ the fclose(stdout) could still fail (due e.g., to a disk full error)
+ when it tries to write out that buffered data. Thus, you would be
+ left with an incomplete output file and the offending program would
+ exit successfully.
+
+ FIXME: note the fflush suggested above is implicit in the fclose
+ we actually do below. Consider doing only the fflush and/or using
+ setvbuf to inhibit buffering.
+
+ Besides, it's wasteful to check the return value from every call
+ that writes to stdout -- just let the internal stream state record
+ the failure. That's what the ferror test is checking below.
+
+ It's important to detect such failures and exit nonzero because many
+ tools (most notably `make' and other build-management systems) depend
+ on being able to detect failure in other tools via their exit status. */
-/* Close standard output, exiting with status STATUS on failure. */
void
close_stdout_status (int status)
{
- if (ferror (stdout))
- error (status, 0, _("write error"));
+ int e = ferror (stdout) ? 0 : -1;
+
+ if (__fpending (stdout) == 0)
+ return;
+
if (fclose (stdout) != 0)
- error (status, errno, _("write error"));
+ e = errno;
+
+ if (0 <= e)
+ {
+ char const *write_error = _("write error");
+ if (file_name)
+ error (status, e, "%s: %s", quotearg_colon (file_name), write_error);
+ else
+ error (status, e, "%s", write_error);
+ }
}
/* Close standard output, exiting with status EXIT_FAILURE on failure. */
void
close_stdout (void)
{
- close_stdout_status (EXIT_FAILURE);
+ close_stdout_status (default_exit_status);
}