diff --git a/daemon/helpers.c b/daemon/helpers.c new file mode 100644 index 0000000..50fde33 --- /dev/null +++ b/daemon/helpers.c @@ -0,0 +1,41 @@ +/* + +Copyright (c) 2017-2019, Feral Interactive +Copyright (c) 2019, Red Hat +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + * Neither the name of Feral Interactive nor the names of its contributors + may be used to endorse or promote products derived from this software + without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +POSSIBILITY OF SUCH DAMAGE. + + */ + +#define _GNU_SOURCE +#include "helpers.h" + +/* Starting with C99 we can use "inline" without "static" and thus avoid + * having multiple (local) definitions of the same inline function. One + * consequence of that is that if the compiler decides to *not* inline + * a specific call to the function the linker will expect an definition. + */ +extern inline void cleanup_close(int *fd); diff --git a/daemon/helpers.h b/daemon/helpers.h index eb2b722..8595092 100644 --- a/daemon/helpers.h +++ b/daemon/helpers.h @@ -34,6 +34,7 @@ POSSIBILITY OF SUCH DAMAGE. #include #include #include +#include /** * Value clamping helper, works like MIN/MAX but constraints a value within the range. @@ -62,3 +63,21 @@ static inline const char *strtail(const char *haystack, const char *needle) return pos; return NULL; } + +/** + * Helper function for autoclosing file-descriptors. Does nothing if the argument + * is NULL or the referenced integer < 0. + */ +inline void cleanup_close(int *fd_ptr) +{ + if (fd_ptr == NULL || *fd_ptr < 0) + return; + + (void)close(*fd_ptr); +} + +/** + * Helper macro for autoclosing file-descriptors: use by prefixing the variable, + * like "autoclose_fd int fd = -1;". + */ +#define autoclose_fd __attribute__((cleanup(cleanup_close))) diff --git a/daemon/meson.build b/daemon/meson.build index 06cb183..d7cd0b5 100644 --- a/daemon/meson.build +++ b/daemon/meson.build @@ -30,6 +30,7 @@ daemon_sources = [ 'daemonize.c', 'dbus_messaging.c', 'daemon_config.c', + 'helpers.c', ] gamemoded_includes = libgamemode_includes