src/doveadm/doveadm-master.c

	doveadm-master.c revision 7237f2f0a577413e12662228ee2039425fd2f5b0
/* Copyright (c) 2010-2016 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "str.h"
#include "istream.h"
#include "write-full.h"
#include "doveadm.h"

#include <unistd.h>
#include <fcntl.h>
#include <signal.h>

#define MASTER_PID_FILE_NAME "master.pid"

static bool pid_file_read(const char *path, pid_t *pid_r)
{
    char buf[32];
    int fd;
    ssize_t ret;
    bool found;

    fd = open(path, O_RDONLY);
    if (fd == -1) {
        if (errno == ENOENT)
            return FALSE;
        i_fatal("open(%s) failed: %m", path);
    }

    ret = read(fd, buf, sizeof(buf)-1);
    if (ret <= 0) {
        if (ret == 0)
            i_error("Empty PID file in %s", path);
        else
            i_fatal("read(%s) failed: %m", path);
        found = FALSE;
    } else {
        if (buf[ret-1] == '\n')
            ret--;
        buf[ret] = '\0';
        if (str_to_pid(buf, pid_r) < 0)
            found = FALSE;
        else {
            found = !(*pid_r == getpid() ||
                  (kill(*pid_r, 0) < 0 && errno == ESRCH));
        }
    }
    i_close_fd(&fd);
    return found;
}

void doveadm_master_send_signal(int signo)
{
    const char *pidfile_path;
    unsigned int i;
    pid_t pid;

    pidfile_path = t_strconcat(doveadm_settings->base_dir,
                   "/"MASTER_PID_FILE_NAME, NULL);

    if (!pid_file_read(pidfile_path, &pid))
        i_fatal("Dovecot is not running (read from %s)", pidfile_path);

    if (kill(pid, signo) < 0)
        i_fatal("kill(%s, %d) failed: %m", dec2str(pid), signo);

    if (signo == SIGTERM) {
        /* wait for a while for the process to die */
        usleep(1000);
        for (i = 0; i < 30; i++) {
            if (kill(pid, 0) < 0) {
                if (errno != ESRCH)
                    i_error("kill() failed: %m");
                break;
            }
            usleep(100000);
        }
    }
}

static void cmd_stop(int argc ATTR_UNUSED, char *argv[] ATTR_UNUSED)
{
    doveadm_master_send_signal(SIGTERM);
}

static void cmd_reload(int argc ATTR_UNUSED, char *argv[] ATTR_UNUSED)
{
    doveadm_master_send_signal(SIGHUP);
}

static struct istream *master_service_send_cmd(const char *cmd)
{
    const char *path;

    path = t_strconcat(doveadm_settings->base_dir, "/master", NULL);
    int fd = net_connect_unix(path);
    if (fd == -1)
        i_fatal("net_connect_unix(%s) failed: %m", path);
    net_set_nonblock(fd, FALSE);

    const char *str =
        t_strdup_printf("VERSION\tmaster-client\t1\t0\n%s\n", cmd);
    if (write_full(fd, str, strlen(str)) < 0)
        i_error("write(%s) failed: %m", path);
    return i_stream_create_fd_autoclose(&fd, IO_BLOCK_SIZE);
}

static void cmd_service_stop(int argc, char *argv[])
{
    const char *line;

    if (argc == 1)
        help_ver2(&doveadm_cmd_service_stop_ver2);

    string_t *cmd = t_str_new(128);
    str_append(cmd, "STOP");
    for (int i = 1; i < argc; i++) {
        str_append_c(cmd, '\t');
        str_append(cmd, argv[i]);
    }
    struct istream *input = master_service_send_cmd(str_c(cmd));

    alarm(5);
    if (i_stream_read_next_line(input) == NULL ||
        (line = i_stream_read_next_line(input)) == NULL) {
        i_error("read(%s) failed: %s", i_stream_get_name(input),
            i_stream_get_error(input));
        doveadm_exit_code = EX_TEMPFAIL;
    } else if (line[0] == '-') {
        doveadm_exit_code = DOVEADM_EX_NOTFOUND;
        i_error("%s", line+1);
    } else if (line[0] != '+') {
        i_error("Unexpected input from %s: %s",
            i_stream_get_name(input), line);
        doveadm_exit_code = EX_TEMPFAIL;
    }
    alarm(0);
    i_stream_destroy(&input);
}

struct doveadm_cmd_ver2 doveadm_cmd_stop_ver2 = {
    .old_cmd = cmd_stop,
    .name = "stop",
    .usage = "",
DOVEADM_CMD_PARAMS_START
DOVEADM_CMD_PARAMS_END
};

struct doveadm_cmd_ver2 doveadm_cmd_reload_ver2 = {
        .old_cmd = cmd_reload,
        .name = "reload",
        .usage = "",
DOVEADM_CMD_PARAMS_START
DOVEADM_CMD_PARAMS_END
};

struct doveadm_cmd_ver2 doveadm_cmd_service_stop_ver2 = {
    .old_cmd = cmd_service_stop,
    .name = "service stop",
    .usage = "<service> [<service> [...]]",
DOVEADM_CMD_PARAMS_START
DOVEADM_CMD_PARAM('\0', "service", CMD_PARAM_ARRAY, CMD_PARAM_FLAG_POSITIONAL)
DOVEADM_CMD_PARAMS_END
};