diff options
Diffstat (limited to 'src/mainloop-signal.c')
-rw-r--r-- | src/mainloop-signal.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/src/mainloop-signal.c b/src/mainloop-signal.c new file mode 100644 index 00000000..dcc72f69 --- /dev/null +++ b/src/mainloop-signal.c @@ -0,0 +1,138 @@ +#include <stdio.h> +#include <assert.h> +#include <signal.h> +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "mainloop-signal.h" +#include "util.h" + +struct signal_info { + int sig; + struct sigaction saved_sigaction; + void (*callback) (void *id, int signal, void *userdata); + void *userdata; + struct signal_info *previous, *next; +}; + +static struct pa_mainloop_api *api = NULL; +static int signal_pipe[2] = { -1, -1 }; +static void* mainloop_source = NULL; +static struct signal_info *signals = NULL; + +static void signal_handler(int sig) { + write(signal_pipe[1], &sig, sizeof(sig)); +} + +static void callback(struct pa_mainloop_api*a, void *id, int fd, enum pa_mainloop_api_io_events events, void *userdata) { + assert(a && id && events == PA_MAINLOOP_API_IO_EVENT_INPUT && id == mainloop_source && fd == signal_pipe[0]); + + for (;;) { + ssize_t r; + int sig; + struct signal_info*s; + + if ((r = read(signal_pipe[0], &sig, sizeof(sig))) < 0) { + if (errno == EAGAIN) + return; + + fprintf(stderr, "signal.c: read(): %s\n", strerror(errno)); + return; + } + + if (r != sizeof(sig)) { + fprintf(stderr, "signal.c: short read()\n"); + return; + } + + for (s = signals; s; s = s->next) + if (s->sig == sig) { + assert(s->callback); + s->callback(s, sig, s->userdata); + break; + } + } +} + +int pa_signal_init(struct pa_mainloop_api *a) { + assert(a); + if (pipe(signal_pipe) < 0) { + fprintf(stderr, "pipe() failed: %s\n", strerror(errno)); + return -1; + } + + make_nonblock_fd(signal_pipe[0]); + make_nonblock_fd(signal_pipe[1]); + + api = a; + mainloop_source = api->source_io(api, signal_pipe[0], PA_MAINLOOP_API_IO_EVENT_INPUT, callback, NULL); + assert(mainloop_source); + return 0; +} + +void pa_signal_done(void) { + assert(api && signal_pipe[0] >= 0 && signal_pipe[1] >= 0 && mainloop_source); + + api->cancel_io(api, mainloop_source); + mainloop_source = NULL; + + close(signal_pipe[0]); + close(signal_pipe[1]); + signal_pipe[0] = signal_pipe[1] = -1; + + while (signals) + pa_signal_unregister(signals); + + api = NULL; +} + +void* pa_signal_register(int sig, void (*callback) (void *id, int signal, void *userdata), void *userdata) { + struct signal_info *s = NULL; + struct sigaction sa; + assert(sig > 0 && callback); + + for (s = signals; s; s = s->next) + if (s->sig == sig) + goto fail; + + s = malloc(sizeof(struct signal_info)); + assert(s); + s->sig = sig; + s->callback = callback; + s->userdata = userdata; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = signal_handler; + sigemptyset(&sa.sa_mask); + sa.sa_flags = SA_RESTART; + + if (sigaction(sig, &sa, &s->saved_sigaction) < 0) + goto fail; + + s->previous = NULL; + s->next = signals; + signals = s; + + return s; +fail: + if (s) + free(s); + return NULL; +} + +void pa_signal_unregister(void *id) { + struct signal_info *s = id; + assert(s); + + if (s->next) + s->next->previous = s->previous; + if (s->previous) + s->previous->next = s->next; + else + signals = s->next; + + sigaction(s->sig, &s->saved_sigaction, NULL); + free(s); +} |