From 29cd838eab01ed7110f3ccb2e8c6a35c8a31dbcc Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:21:29 +0200 Subject: Adding upstream version 1:0.1.9998svn3589+dfsg. Signed-off-by: Daniel Baumann --- src/grep/lib/closeout.c | 136 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 136 insertions(+) create mode 100644 src/grep/lib/closeout.c (limited to 'src/grep/lib/closeout.c') diff --git a/src/grep/lib/closeout.c b/src/grep/lib/closeout.c new file mode 100644 index 0000000..a0c935f --- /dev/null +++ b/src/grep/lib/closeout.c @@ -0,0 +1,136 @@ +/* Close standard output and standard error, exiting with a diagnostic on error. + + Copyright (C) 1998-2002, 2004, 2006, 2008-2021 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 . */ + +#include + +#include "closeout.h" + +#include +#include +#include +#include + +#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); +} -- cgit v1.2.3