blob: 8499b35188c5c2931b931764cc8cce02690aa0cd [file] [log] [blame]
/*
* Wrapper to make haproxy systemd-compliant.
*
* Copyright 2013 Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <errno.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
static char *pid_file = "/run/haproxy.pid";
static int main_argc;
static char **main_argv;
static void spawn_haproxy(char **pid_strv, int nb_pid)
{
pid_t pid = fork();
if (!pid) {
/* 3 for "haproxy -Ds -sf" */
char **argv = calloc(4 + main_argc + nb_pid + 1, sizeof(char *));
int i;
int argno = 0;
argv[argno++] = SBINDIR"/haproxy";
for (i = 0; i < main_argc; ++i)
argv[argno++] = main_argv[i];
argv[argno++] = "-Ds";
if (nb_pid > 0) {
argv[argno++] = "-sf";
for (i = 0; i < nb_pid; ++i)
argv[argno++] = pid_strv[i];
}
argv[argno] = NULL;
execv(argv[0], argv);
exit(0);
}
}
static int read_pids(char ***pid_strv)
{
FILE *f = fopen(pid_file, "r");
int read = 0, allocated = 8;
char pid_str[10];
if (!f)
return 0;
*pid_strv = malloc(allocated * sizeof(char *));
while (1 == fscanf(f, "%s\n", pid_str)) {
if (read == allocated) {
allocated *= 2;
*pid_strv = realloc(*pid_strv, allocated * sizeof(char *));
}
(*pid_strv)[read++] = strdup(pid_str);
}
fclose(f);
return read;
}
static void signal_handler(int signum __attribute__((unused)))
{
int i;
char **pid_strv = NULL;
int nb_pid = read_pids(&pid_strv);
spawn_haproxy(pid_strv, nb_pid);
for (i = 0; i < nb_pid; ++i)
free(pid_strv[i]);
free(pid_strv);
}
static void init(int argc, char **argv)
{
while (argc > 1) {
if (**argv == '-') {
char *flag = *argv + 1;
--argc; ++argv;
if (*flag == 'p')
pid_file = *argv;
}
--argc; ++argv;
}
}
int main(int argc, char **argv)
{
--argc; ++argv;
main_argc = argc;
main_argv = argv;
init(argc, argv);
signal(SIGUSR2, &signal_handler);
spawn_haproxy(NULL, 0);
while (-1 != wait(NULL) || errno == EINTR);
return EXIT_SUCCESS;
}