+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2013 Zbigniew Jędrzejewski-Szmek
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <unistd.h>
-#include <sys/epoll.h>
-#include <sys/prctl.h>
-#include <sys/socket.h>
-#include <sys/wait.h>
-#include <getopt.h>
-
-#include "systemd/sd-daemon.h"
-
-#include "socket-util.h"
-#include "build.h"
-#include "log.h"
-#include "strv.h"
-#include "macro.h"
-
-static char** arg_listen = NULL;
-static bool arg_accept = false;
-static char** arg_args = NULL;
-static char** arg_setenv = NULL;
-
-static int add_epoll(int epoll_fd, int fd) {
- struct epoll_event ev = {
- .events = EPOLLIN
- };
- int r;
-
- assert(epoll_fd >= 0);
- assert(fd >= 0);
-
- ev.data.fd = fd;
- r = epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &ev);
- if (r < 0)
- return log_error_errno(errno, "Failed to add event on epoll fd:%d for fd:%d: %m", epoll_fd, fd);
-
- return 0;
-}
-
-static int open_sockets(int *epoll_fd, bool accept) {
- char **address;
- int n, fd, r;
- int count = 0;
-
- n = sd_listen_fds(true);
- if (n < 0)
- return log_error_errno(n, "Failed to read listening file descriptors from environment: %m");
- if (n > 0) {
- log_info("Received %i descriptors via the environment.", n);
-
- for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd++) {
- r = fd_cloexec(fd, arg_accept);
- if (r < 0)
- return r;
-
- count ++;
- }
- }
-
- /* Close logging and all other descriptors */
- if (arg_listen) {
- int except[3 + n];
-
- for (fd = 0; fd < SD_LISTEN_FDS_START + n; fd++)
- except[fd] = fd;
-
- log_close();
- close_all_fds(except, 3 + n);
- }
-
- /** Note: we leak some fd's on error here. I doesn't matter
- * much, since the program will exit immediately anyway, but
- * would be a pain to fix.
- */
-
- STRV_FOREACH(address, arg_listen) {
-
- fd = make_socket_fd(LOG_DEBUG, *address, SOCK_STREAM | (arg_accept*SOCK_CLOEXEC));
- if (fd < 0) {
- log_open();
- return log_error_errno(fd, "Failed to open '%s': %m", *address);
- }
-
- assert(fd == SD_LISTEN_FDS_START + count);
- count ++;
- }
-
- if (arg_listen)
- log_open();
-
- *epoll_fd = epoll_create1(EPOLL_CLOEXEC);
- if (*epoll_fd < 0)
- return log_error_errno(errno, "Failed to create epoll object: %m");
-
- for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + count; fd++) {
- _cleanup_free_ char *name = NULL;
-
- getsockname_pretty(fd, &name);
- log_info("Listening on %s as %i.", strna(name), fd);
-
- r = add_epoll(*epoll_fd, fd);
- if (r < 0)
- return r;
- }
-
- return count;
-}
-
-static int launch(char* name, char **argv, char **env, int fds) {
-
- static const char* tocopy[] = {"TERM=", "PATH=", "USER=", "HOME="};
- _cleanup_strv_free_ char **envp = NULL;
- _cleanup_free_ char *tmp = NULL;
- unsigned n_env = 0, length;
- char **s;
- unsigned i;
-
- length = strv_length(arg_setenv);
-
- /* PATH, TERM, HOME, USER, LISTEN_FDS, LISTEN_PID, NULL */
- envp = new0(char *, length + 7);
- if (!envp)
- return log_oom();
-
- STRV_FOREACH(s, arg_setenv) {
- if (strchr(*s, '='))
- envp[n_env++] = *s;
- else {
- _cleanup_free_ char *p = strappend(*s, "=");
- if (!p)
- return log_oom();
- envp[n_env] = strv_find_prefix(env, p);
- if (envp[n_env])
- n_env ++;
- }
- }
-
- for (i = 0; i < ELEMENTSOF(tocopy); i++) {
- envp[n_env] = strv_find_prefix(env, tocopy[i]);
- if (envp[n_env])
- n_env ++;
- }
-
- if ((asprintf((char**)(envp + n_env++), "LISTEN_FDS=%d", fds) < 0) ||
- (asprintf((char**)(envp + n_env++), "LISTEN_PID=%d", getpid()) < 0))
- return log_oom();
-
- tmp = strv_join(argv, " ");
- if (!tmp)
- return log_oom();
-
- log_info("Execing %s (%s)", name, tmp);
- execvpe(name, argv, envp);
- log_error_errno(errno, "Failed to execp %s (%s): %m", name, tmp);
-
- return -errno;
-}
-
-static int launch1(const char* child, char** argv, char **env, int fd) {
- _cleanup_free_ char *tmp = NULL;
- pid_t parent_pid, child_pid;
- int r;
-
- tmp = strv_join(argv, " ");
- if (!tmp)
- return log_oom();
-
- parent_pid = getpid();
-
- child_pid = fork();
- if (child_pid < 0)
- return log_error_errno(errno, "Failed to fork: %m");
-
- /* In the child */
- if (child_pid == 0) {
- r = dup2(fd, STDIN_FILENO);
- if (r < 0) {
- log_error_errno(errno, "Failed to dup connection to stdin: %m");
- _exit(EXIT_FAILURE);
- }
-
- r = dup2(fd, STDOUT_FILENO);
- if (r < 0) {
- log_error_errno(errno, "Failed to dup connection to stdout: %m");
- _exit(EXIT_FAILURE);
- }
-
- r = close(fd);
- if (r < 0) {
- log_error_errno(errno, "Failed to close dupped connection: %m");
- _exit(EXIT_FAILURE);
- }
-
- /* Make sure the child goes away when the parent dies */
- if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
- _exit(EXIT_FAILURE);
-
- /* Check whether our parent died before we were able
- * to set the death signal */
- if (getppid() != parent_pid)
- _exit(EXIT_SUCCESS);
-
- execvp(child, argv);
- log_error_errno(errno, "Failed to exec child %s: %m", child);
- _exit(EXIT_FAILURE);
- }
-
- log_info("Spawned %s (%s) as PID %d", child, tmp, child_pid);
-
- return 0;
-}
-
-static int do_accept(const char* name, char **argv, char **envp, int fd) {
- _cleanup_free_ char *local = NULL, *peer = NULL;
- _cleanup_close_ int fd2 = -1;
-
- fd2 = accept(fd, NULL, NULL);
- if (fd2 < 0) {
- log_error_errno(errno, "Failed to accept connection on fd:%d: %m", fd);
- return fd2;
- }
-
- getsockname_pretty(fd2, &local);
- getpeername_pretty(fd2, &peer);
- log_info("Connection from %s to %s", strna(peer), strna(local));
-
- return launch1(name, argv, envp, fd2);
-}
-
-/* SIGCHLD handler. */
-static void sigchld_hdl(int sig, siginfo_t *t, void *data) {
- PROTECT_ERRNO;
-
- log_info("Child %d died with code %d", t->si_pid, t->si_status);
- /* Wait for a dead child. */
- waitpid(t->si_pid, NULL, 0);
-}
-
-static int install_chld_handler(void) {
- int r;
- struct sigaction act = {
- .sa_flags = SA_SIGINFO,
- .sa_sigaction = sigchld_hdl,
- };
-
- r = sigaction(SIGCHLD, &act, 0);
- if (r < 0)
- log_error_errno(errno, "Failed to install SIGCHLD handler: %m");
- return r;
-}
-
-static void help(void) {
- printf("%s [OPTIONS...]\n\n"
- "Listen on sockets and launch child on connection.\n\n"
- "Options:\n"
- " -l --listen=ADDR Listen for raw connections at ADDR\n"
- " -a --accept Spawn separate child for each connection\n"
- " -h --help Show this help and exit\n"
- " -E --setenv=NAME[=VALUE] Pass an environment variable to children\n"
- " --version Print version string and exit\n"
- "\n"
- "Note: file descriptors from sd_listen_fds() will be passed through.\n"
- , program_invocation_short_name);
-}
-
-static int parse_argv(int argc, char *argv[]) {
- enum {
- ARG_VERSION = 0x100,
- };
-
- static const struct option options[] = {
- { "help", no_argument, NULL, 'h' },
- { "version", no_argument, NULL, ARG_VERSION },
- { "listen", required_argument, NULL, 'l' },
- { "accept", no_argument, NULL, 'a' },
- { "setenv", required_argument, NULL, 'E' },
- { "environment", required_argument, NULL, 'E' }, /* alias */
- {}
- };
-
- int c;
-
- assert(argc >= 0);
- assert(argv);
-
- while ((c = getopt_long(argc, argv, "+hl:aE:", options, NULL)) >= 0)
- switch(c) {
- case 'h':
- help();
- return 0;
-
- case ARG_VERSION:
- puts(PACKAGE_STRING);
- puts(SYSTEMD_FEATURES);
- return 0 /* done */;
-
- case 'l': {
- int r = strv_extend(&arg_listen, optarg);
- if (r < 0)
- return r;
-
- break;
- }
-
- case 'a':
- arg_accept = true;
- break;
-
- case 'E': {
- int r = strv_extend(&arg_setenv, optarg);
- if (r < 0)
- return r;
-
- break;
- }
-
- case '?':
- return -EINVAL;
-
- default:
- assert_not_reached("Unhandled option");
- }
-
- if (optind == argc) {
- log_error("%s: command to execute is missing.",
- program_invocation_short_name);
- return -EINVAL;
- }
-
- arg_args = argv + optind;
-
- return 1 /* work to do */;
-}
-
-int main(int argc, char **argv, char **envp) {
- int r, n;
- int epoll_fd = -1;
-
- log_parse_environment();
- log_open();
-
- r = parse_argv(argc, argv);
- if (r <= 0)
- return r == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
-
- r = install_chld_handler();
- if (r < 0)
- return EXIT_FAILURE;
-
- n = open_sockets(&epoll_fd, arg_accept);
- if (n < 0)
- return EXIT_FAILURE;
- if (n == 0) {
- log_error("No sockets to listen on specified or passed in.");
- return EXIT_FAILURE;
- }
-
- for (;;) {
- struct epoll_event event;
-
- r = epoll_wait(epoll_fd, &event, 1, -1);
- if (r < 0) {
- if (errno == EINTR)
- continue;
-
- log_error_errno(errno, "epoll_wait() failed: %m");
- return EXIT_FAILURE;
- }
-
- log_info("Communication attempt on fd %i.", event.data.fd);
- if (arg_accept) {
- r = do_accept(argv[optind], argv + optind, envp,
- event.data.fd);
- if (r < 0)
- return EXIT_FAILURE;
- } else
- break;
- }
-
- launch(argv[optind], argv + optind, envp, n);
-
- return EXIT_SUCCESS;
-}
~ianmdlvl / elogind.git / blobdiff