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#include "signal-handler.h"
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <sys/signalfd.h>
#include <sys/types.h>
#include <unistd.h>
#include "block.h"
#include "main.h"
#include "timer.h"
typedef struct signalfd_siginfo signal_info;
signal_handler signal_handler_new(
block *const blocks, const unsigned short block_count,
const signal_refresh_callback refresh_callback,
const signal_timer_callback timer_callback) {
signal_handler handler = {
.refresh_callback = refresh_callback,
.timer_callback = timer_callback,
.blocks = blocks,
.block_count = block_count,
};
return handler;
}
int signal_handler_init(signal_handler *const handler) {
signal_set set;
(void)sigemptyset(&set);
// Handle user-generated signal for refreshing the status.
(void)sigaddset(&set, REFRESH_SIGNAL);
// Handle SIGALRM generated by the timer.
(void)sigaddset(&set, TIMER_SIGNAL);
// Handle termination signals.
(void)sigaddset(&set, SIGINT);
(void)sigaddset(&set, SIGTERM);
for (unsigned short i = 0; i < handler->block_count; ++i) {
const block *const block = &handler->blocks[i];
if (block->signal > 0) {
if (sigaddset(&set, SIGRTMIN + block->signal) != 0) {
(void)fprintf(
stderr,
"error: invalid or unsupported signal specified for "
"\"%s\" block\n",
block->command);
return 1;
}
}
}
// Create a signal file descriptor for epoll to watch.
handler->fd = signalfd(-1, &set, 0);
if (handler->fd == -1) {
(void)fprintf(stderr,
"error: could not create file descriptor for signals\n");
return 1;
}
// Block all realtime and handled signals.
for (int i = SIGRTMIN; i <= SIGRTMAX; ++i) {
(void)sigaddset(&set, i);
}
(void)sigprocmask(SIG_BLOCK, &set, NULL);
return 0;
}
int signal_handler_deinit(signal_handler *const handler) {
if (close(handler->fd) != 0) {
(void)fprintf(stderr,
"error: could not close signal file descriptor\n");
return 1;
}
return 0;
}
int signal_handler_process(signal_handler *const handler, timer *const timer) {
signal_info info;
const ssize_t bytes_read = read(handler->fd, &info, sizeof(info));
if (bytes_read == -1) {
(void)fprintf(stderr, "error: could not read info of incoming signal");
return 1;
}
const int signal = (int)info.ssi_signo;
switch (signal) {
case TIMER_SIGNAL:
if (handler->timer_callback(handler->blocks, handler->block_count,
timer) != 0) {
return 1;
}
return 0;
case REFRESH_SIGNAL:
if (handler->refresh_callback(handler->blocks,
handler->block_count) != 0) {
return 1;
}
return 0;
case SIGTERM:
// fall through
case SIGINT:
return 1;
}
for (unsigned short i = 0; i < handler->block_count; ++i) {
block *const block = &handler->blocks[i];
if (block->signal == signal - SIGRTMIN) {
const uint8_t button = (uint8_t)info.ssi_int;
block_execute(block, button);
break;
}
}
return 0;
}
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