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/*
* blogc: A blog compiler.
* Copyright (C) 2014-2017 Rafael G. Martins <rafael@rafaelmartins.eng.br>
*
* This program can be distributed under the terms of the BSD License.
* See the file LICENSE.
*/
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
#include <errno.h>
#include "../common/utils.h"
#include "ctx.h"
#include "rules.h"
#include "reloader.h"
// we are not going to unit-test these functions, then printing errors
// directly is not a big issue
static pthread_mutex_t mutex_running = PTHREAD_MUTEX_INITIALIZER;
static bool running = false;
static int handler_signum = 0;
static void (*handler_func)(int) = NULL;
int
bm_reloader_run(bm_ctx_t **ctx, bm_rule_exec_func_t rule_exec,
bc_slist_t *outputs, bc_trie_t *args)
{
// install ^C handler
struct sigaction current_action;
if (sigaction(SIGINT, NULL, ¤t_action) < 0) {
fprintf(stderr, "blogc-make: failed to run reloader: %s\n", strerror(errno));
return 3;
}
if (current_action.sa_handler != bm_reloader_stop) { // not installed yet
// backup current handler
pthread_mutex_lock(&mutex_running);
handler_func = current_action.sa_handler;
pthread_mutex_unlock(&mutex_running);
// set new handler
struct sigaction new_action;
new_action.sa_handler = bm_reloader_stop;
sigemptyset(&new_action.sa_mask);
new_action.sa_flags = 0;
if (sigaction(SIGINT, &new_action, NULL) < 0) {
fprintf(stderr, "blogc-make: failed to run reloader: %s\n",
strerror(errno));
return 3;
}
}
pthread_mutex_lock(&mutex_running);
running = true;
pthread_mutex_unlock(&mutex_running);
while (running) {
if (!bm_ctx_reload(ctx)) {
fprintf(stderr, "blogc-make: warning: failed to reload context. "
"retrying in 5 seconds ...\n\n");
sleep(5);
continue;
}
if (0 != rule_exec(*ctx, outputs, args)) {
fprintf(stderr, "blogc-make: warning: failed to rebuild website. "
"retrying in 5 seconds ...\n\n");
sleep(5);
continue;
}
sleep(1);
}
if (handler_signum > 0 && handler_signum <= SIGRTMAX)
return 128 + handler_signum;
return handler_signum;
}
void
bm_reloader_stop(int signum)
{
pthread_mutex_lock(&mutex_running);
handler_signum = signum > 128 ? signum - 128 : signum;
running = false;
// reraise if SIGINT
if (handler_signum == SIGINT) {
// reinstall old ^C handler
struct sigaction new_action;
new_action.sa_handler = handler_func;
sigemptyset(&new_action.sa_mask);
new_action.sa_flags = 0;
sigaction(SIGINT, &new_action, NULL);
// run it
raise(SIGINT);
// SIGINT will usually kill the process, but in the case that the
// `handler_func` prevents it, our custom handler will be reinstalled
// by `bm_reloader_run`.
}
pthread_mutex_unlock(&mutex_running);
}
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