X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fcloseout.c;h=830f16f8ae8a6e7f6177b0ace34a387708e5043e;hb=c68c756f05b4d51ffa5a12b391ff996990deee14;hp=b0eed90eae2c875e0156f9dc55915523e7046917;hpb=d17327237fac6d781a90bf928ba0d88aed472772;p=gnulib.git diff --git a/lib/closeout.c b/lib/closeout.c index b0eed90ea..830f16f8a 100644 --- a/lib/closeout.c +++ b/lib/closeout.c @@ -1,7 +1,7 @@ -/* closeout.c - close standard output +/* Close standard output and standard error, exiting with a diagnostic on error. - Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004 Free Software - Foundation, Inc. + Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2006 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 @@ -15,28 +15,24 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, - Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ -#if HAVE_CONFIG_H -# include -#endif +#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" -#if USE_UNLOCKED_IO -# include "unlocked-io.h" -#endif - static const char *file_name; /* Set the file name to be reported in the event an error is detected @@ -47,22 +43,24 @@ close_stdout_set_file_name (const char *file) file_name = file; } -/* Close standard output, exiting with status 'exit_failure' on failure. - If a program writes *anything* to stdout, that program should close - 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. Even calling fflush is not always sufficient, - since some file systems (NFS and CODA) buffer written/flushed data - until an actual close call. - - 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. +/* 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 @@ -71,18 +69,18 @@ close_stdout_set_file_name (const char *file) void close_stdout (void) { - int e = ferror (stdout) ? 0 : -1; - - if (fclose (stdout) != 0) - e = errno; - - if (0 <= e) + if (close_stream (stdout) != 0) { char const *write_error = _("write error"); if (file_name) - error (exit_failure, e, "%s: %s", quotearg_colon (file_name), + error (0, errno, "%s: %s", quotearg_colon (file_name), write_error); else - error (exit_failure, e, "%s", write_error); + error (0, errno, "%s", write_error); + + _exit (exit_failure); } + + if (close_stream (stderr) != 0) + _exit (exit_failure); }