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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 16:11:47 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 16:11:47 +0000
commit758f820bcc0f68aeebac1717e537ca13a320b909 (patch)
tree48111ece75cf4f98316848b37a7e26356e00669e /lib/closeout.c
parentInitial commit. (diff)
downloadcoreutils-upstream.tar.xz
coreutils-upstream.zip
Adding upstream version 9.1.upstream/9.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/closeout.c')
-rw-r--r--lib/closeout.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/lib/closeout.c b/lib/closeout.c
new file mode 100644
index 0000000..688cd73
--- /dev/null
+++ b/lib/closeout.c
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+/* Close standard output and standard error, exiting with a diagnostic on error.
+
+ Copyright (C) 1998-2002, 2004, 2006, 2008-2022 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
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include "closeout.h"
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "gettext.h"
+#define _(msgid) gettext (msgid)
+
+#include "close-stream.h"
+#include "error.h"
+#include "exitfail.h"
+#include "quotearg.h"
+
+#ifndef __has_feature
+# define __has_feature(a) false
+#endif
+
+#if defined __SANITIZE_ADDRESS__ || __has_feature (address_sanitizer)
+enum { SANITIZE_ADDRESS = true };
+#else
+enum { SANITIZE_ADDRESS = false };
+#endif
+
+static const char *file_name;
+
+/* Set the file name to be reported in the event an error is detected
+ by close_stdout. */
+void
+close_stdout_set_file_name (const char *file)
+{
+ file_name = file;
+}
+
+static bool ignore_EPIPE /* = false */;
+
+/* Specify the reaction to an EPIPE error during the closing of stdout:
+ - If ignore = true, it shall be ignored.
+ - If ignore = false, it shall evoke a diagnostic, along with a nonzero
+ exit status.
+ The default is ignore = false.
+
+ This setting matters only if the SIGPIPE signal is ignored (i.e. its
+ handler set to SIG_IGN) or blocked. Only particular programs need to
+ temporarily ignore SIGPIPE. If SIGPIPE is ignored or blocked because
+ it was ignored or blocked in the parent process when it created the
+ child process, it usually is a bug in the parent process: It is bad
+ practice to have SIGPIPE ignored or blocked while creating a child
+ process.
+
+ EPIPE occurs when writing to a pipe or socket that has no readers now,
+ when SIGPIPE is ignored or blocked.
+
+ The ignore = false setting is suitable for a scenario where it is normally
+ guaranteed that the pipe writer terminates before the pipe reader. In
+ this case, an EPIPE is an indication of a premature termination of the
+ pipe reader and should lead to a diagnostic and a nonzero exit status.
+
+ The ignore = true setting is suitable for a scenario where you don't know
+ ahead of time whether the pipe writer or the pipe reader will terminate
+ first. In this case, an EPIPE is an indication that the pipe writer can
+ stop doing useless write() calls; this is what close_stdout does anyway.
+ EPIPE is part of the normal pipe/socket shutdown protocol in this case,
+ and should not lead to a diagnostic message. */
+
+void
+close_stdout_set_ignore_EPIPE (bool ignore)
+{
+ ignore_EPIPE = ignore;
+}
+
+/* Close standard output. On error, issue a diagnostic and _exit
+ with status 'exit_failure'.
+
+ Also close standard error. On error, _exit with status 'exit_failure'.
+
+ Since close_stdout is commonly registered via 'atexit', POSIX
+ and the C standard both say that it should not call 'exit',
+ because the behavior is undefined if 'exit' is called more than
+ once. So it calls '_exit' instead of 'exit'. If close_stdout
+ is registered via atexit before other functions are registered,
+ the other functions can act before this _exit is invoked.
+
+ Applications that use close_stdout should flush any streams
+ other than stdout and stderr before exiting, since the call to
+ _exit will bypass other buffer flushing. Applications should
+ be flushing and closing other streams anyway, to check for I/O
+ errors. Also, applications should not use tmpfile, since _exit
+ can bypass the removal of these files.
+
+ 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. */
+
+void
+close_stdout (void)
+{
+ if (close_stream (stdout) != 0
+ && !(ignore_EPIPE && errno == EPIPE))
+ {
+ char const *write_error = _("write error");
+ if (file_name)
+ error (0, errno, "%s: %s", quotearg_colon (file_name),
+ write_error);
+ else
+ error (0, errno, "%s", write_error);
+
+ _exit (exit_failure);
+ }
+
+ /* Close stderr only if not sanitizing, as sanitizers may report to
+ stderr after this function returns. */
+ if (!SANITIZE_ADDRESS && close_stream (stderr) != 0)
+ _exit (exit_failure);
+}