diff options
Diffstat (limited to 'src/pulse/mainloop-signal.c')
| -rw-r--r-- | src/pulse/mainloop-signal.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/src/pulse/mainloop-signal.c b/src/pulse/mainloop-signal.c new file mode 100644 index 0000000..f196ad3 --- /dev/null +++ b/src/pulse/mainloop-signal.c @@ -0,0 +1,224 @@ +/*** + This file is part of PulseAudio. + + Copyright 2004-2008 Lennart Poettering + Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB + + PulseAudio is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2.1 of the License, + or (at your option) any later version. + + PulseAudio 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 Lesser General Public License + along with PulseAudio; if not, see <http://www.gnu.org/licenses/>. +***/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> +#include <signal.h> +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#ifdef HAVE_WINDOWS_H +#include <windows.h> +#endif + +#include <pulse/xmalloc.h> + +#include <pulsecore/core-error.h> +#include <pulsecore/core-util.h> +#include <pulsecore/i18n.h> +#include <pulsecore/log.h> +#include <pulsecore/macro.h> + +#include "mainloop-signal.h" + +struct pa_signal_event { + int sig; +#ifdef HAVE_SIGACTION + struct sigaction saved_sigaction; +#else + void (*saved_handler)(int sig); +#endif + void *userdata; + pa_signal_cb_t callback; + pa_signal_destroy_cb_t destroy_callback; + pa_signal_event *previous, *next; +}; + +static pa_mainloop_api *api = NULL; +static int signal_pipe[2] = { -1, -1 }; +static pa_io_event* io_event = NULL; +static pa_signal_event *signals = NULL; + +static void signal_handler(int sig) { + int saved_errno; + + saved_errno = errno; + +#ifndef HAVE_SIGACTION + signal(sig, signal_handler); +#endif + + /* XXX: If writing fails, there's nothing we can do? */ + (void) pa_write(signal_pipe[1], &sig, sizeof(sig), NULL); + + errno = saved_errno; +} + +static void dispatch(pa_mainloop_api*a, int sig) { + pa_signal_event *s; + + for (s = signals; s; s = s->next) + if (s->sig == sig) { + pa_assert(s->callback); + s->callback(a, s, sig, s->userdata); + break; + } +} + +static void callback(pa_mainloop_api*a, pa_io_event*e, int fd, pa_io_event_flags_t f, void *userdata) { + ssize_t r; + int sig; + + pa_assert(a); + pa_assert(e); + pa_assert(f == PA_IO_EVENT_INPUT); + pa_assert(e == io_event); + pa_assert(fd == signal_pipe[0]); + + if ((r = pa_read(signal_pipe[0], &sig, sizeof(sig), NULL)) < 0) { + if (errno == EAGAIN) + return; + + pa_log("read(): %s", pa_cstrerror(errno)); + return; + } + + if (r != sizeof(sig)) { + pa_log("short read()"); + return; + } + + dispatch(a, sig); +} + +int pa_signal_init(pa_mainloop_api *a) { + + pa_assert(a); + pa_assert(!api); + pa_assert(signal_pipe[0] == -1); + pa_assert(signal_pipe[1] == -1); + pa_assert(!io_event); + + if (pa_pipe_cloexec(signal_pipe) < 0) { + pa_log("pipe(): %s", pa_cstrerror(errno)); + return -1; + } + + pa_make_fd_nonblock(signal_pipe[0]); + pa_make_fd_nonblock(signal_pipe[1]); + + api = a; + + pa_assert_se(io_event = api->io_new(api, signal_pipe[0], PA_IO_EVENT_INPUT, callback, NULL)); + + return 0; +} + +void pa_signal_done(void) { + while (signals) + pa_signal_free(signals); + + if (io_event) { + pa_assert(api); + api->io_free(io_event); + io_event = NULL; + } + + pa_close_pipe(signal_pipe); + + api = NULL; +} + +pa_signal_event* pa_signal_new(int sig, pa_signal_cb_t _callback, void *userdata) { + pa_signal_event *e = NULL; + +#ifdef HAVE_SIGACTION + struct sigaction sa; +#endif + + pa_assert(sig > 0); + pa_assert(_callback); + + pa_init_i18n(); + + for (e = signals; e; e = e->next) + if (e->sig == sig) + return NULL; + + e = pa_xnew(pa_signal_event, 1); + e->sig = sig; + e->callback = _callback; + e->userdata = userdata; + e->destroy_callback = NULL; + +#ifdef HAVE_SIGACTION + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = signal_handler; + sigemptyset(&sa.sa_mask); + sa.sa_flags = SA_RESTART; + + if (sigaction(sig, &sa, &e->saved_sigaction) < 0) +#else + if ((e->saved_handler = signal(sig, signal_handler)) == SIG_ERR) +#endif + goto fail; + + e->previous = NULL; + e->next = signals; + signals = e; + + return e; +fail: + pa_xfree(e); + return NULL; +} + +void pa_signal_free(pa_signal_event *e) { + pa_assert(e); + + if (e->next) + e->next->previous = e->previous; + if (e->previous) + e->previous->next = e->next; + else + signals = e->next; + +#ifdef HAVE_SIGACTION + pa_assert_se(sigaction(e->sig, &e->saved_sigaction, NULL) == 0); +#else + pa_assert_se(signal(e->sig, e->saved_handler) == signal_handler); +#endif + + if (e->destroy_callback) + e->destroy_callback(api, e, e->userdata); + + pa_xfree(e); +} + +void pa_signal_set_destroy(pa_signal_event *e, pa_signal_destroy_cb_t _callback) { + pa_assert(e); + + e->destroy_callback = _callback; +} |