X-Git-Url: https://vcs.fsf.org/?a=blobdiff_plain;f=src%2Fsrc%2Fdaemon.c;h=55e14776fe508be16d062ae6b7b028bf9839981b;hb=54c5ebb14ead7439af300e9d7d9d7d2ba29ff32e;hp=caf8cb24e08cb70da9a9b7195beed3bc83b8e71b;hpb=d17610eb5e5c37609dac69f50986fe0943edf135;p=exim.git diff --git a/src/src/daemon.c b/src/src/daemon.c index caf8cb24e..55e14776f 100644 --- a/src/src/daemon.c +++ b/src/src/daemon.c @@ -1,4 +1,4 @@ -/* $Cambridge: exim/src/src/daemon.c,v 1.7 2005/01/27 15:15:30 ph10 Exp $ */ +/* $Cambridge: exim/src/src/daemon.c,v 1.13 2005/06/27 14:29:43 ph10 Exp $ */ /************************************************* * Exim - an Internet mail transport agent * @@ -39,8 +39,8 @@ static int accept_retry_errno; static BOOL accept_retry_select_failed; static int queue_run_count = 0; -static pid_t *queue_pid_slots; -static smtp_slot *smtp_slots; +static pid_t *queue_pid_slots = NULL; +static smtp_slot *smtp_slots = NULL; static BOOL write_pid = TRUE; @@ -142,7 +142,7 @@ handle_smtp_call(int *listen_sockets, int listen_socket_count, { pid_t pid; union sockaddr_46 interface_sockaddr; -SOCKLEN_T ifsize = sizeof(interface_sockaddr); +EXIM_SOCKLEN_T ifsize = sizeof(interface_sockaddr); int dup_accept_socket = -1; int max_for_this_host = 0; int wfsize = 0; @@ -362,7 +362,7 @@ if (pid == 0) int i; int queue_only_reason = 0; int old_pool = store_pool; - int save_debug_selector = debug_selector; + int save_debug_selector = debug_selector; BOOL local_queue_only; #ifdef SA_NOCLDWAIT struct sigaction act; @@ -419,7 +419,7 @@ if (pid == 0) extensive comment before the reception loop in exim.c for a fuller explanation of this logic. */ - for (i = 0; i < listen_socket_count; i++) close(listen_sockets[i]); + for (i = 0; i < listen_socket_count; i++) (void)close(listen_sockets[i]); #ifdef SA_NOCLDWAIT act.sa_handler = SIG_IGN; @@ -433,16 +433,16 @@ if (pid == 0) /* Attempt to get an id from the sending machine via the RFC 1413 protocol. We do this in the sub-process in order not to hold up the main process if there is any delay. Then set up the fullhost information - in case there is no HELO/EHLO. - - If debugging is enabled only for the daemon, we must turn if off while - finding the id, but turn it on again afterwards so that information about the + in case there is no HELO/EHLO. + + If debugging is enabled only for the daemon, we must turn if off while + finding the id, but turn it on again afterwards so that information about the incoming connection is output. */ - + if (debug_daemon) debug_selector = 0; verify_get_ident(IDENT_PORT); host_build_sender_fullhost(); - debug_selector = save_debug_selector; + debug_selector = save_debug_selector; DEBUG(D_any) debug_printf("Process %d is handling incoming connection from %s\n", @@ -603,8 +603,8 @@ if (pid == 0) if ((dpid = fork()) == 0) { - fclose(smtp_in); - fclose(smtp_out); + (void)fclose(smtp_in); + (void)fclose(smtp_out); /* Don't ever molest the parent's SSL connection, but do clean up the data structures if necessary. */ @@ -691,7 +691,7 @@ if (smtp_out != NULL) strerror(errno)); smtp_out = NULL; } -else close(accept_socket); +else (void)close(accept_socket); if (smtp_in != NULL) { @@ -700,7 +700,7 @@ if (smtp_in != NULL) strerror(errno)); smtp_in = NULL; } -else close(dup_accept_socket); +else (void)close(dup_accept_socket); /* Release any store used in this process, including the store used for holding the incoming host address and an expanded active_hostname. */ @@ -776,6 +776,72 @@ return FALSE; +/************************************************* +* Handle terminating subprocesses * +*************************************************/ + +/* Handle the termination of child processes. Theoretically, this need be done +only when sigchld_seen is TRUE, but rumour has it that some systems lose +SIGCHLD signals at busy times, so to be on the safe side, this function is +called each time round. It shouldn't be too expensive. + +Arguments: none +Returns: nothing +*/ + +static void +handle_ending_processes(void) +{ +int status; +pid_t pid; + +while ((pid = waitpid(-1, &status, WNOHANG)) > 0) + { + int i; + DEBUG(D_any) debug_printf("child %d ended: status=0x%x\n", (int)pid, + status); + + /* If it's a listening daemon for which we are keeping track of individual + subprocesses, deal with an accepting process that has terminated. */ + + if (smtp_slots != NULL) + { + for (i = 0; i < smtp_accept_max; i++) + { + if (smtp_slots[i].pid == pid) + { + if (smtp_slots[i].host_address != NULL) + store_free(smtp_slots[i].host_address); + smtp_slots[i] = empty_smtp_slot; + if (--smtp_accept_count < 0) smtp_accept_count = 0; + DEBUG(D_any) debug_printf("%d SMTP accept process%s now running\n", + smtp_accept_count, (smtp_accept_count == 1)? "" : "es"); + break; + } + } + if (i < smtp_accept_max) continue; /* Found an accepting process */ + } + + /* If it wasn't an accepting process, see if it was a queue-runner + process that we are tracking. */ + + if (queue_pid_slots != NULL) + { + for (i = 0; i < queue_run_max; i++) + { + if (queue_pid_slots[i] == pid) + { + queue_pid_slots[i] = 0; + if (--queue_run_count < 0) queue_run_count = 0; + DEBUG(D_any) debug_printf("%d queue-runner process%s now running\n", + queue_run_count, (queue_run_count == 1)? "" : "es"); + break; + } + } + } + } +} + /************************************************* @@ -899,7 +965,7 @@ if (daemon_listen) #ifdef LOAD_AVG_NEEDS_ROOT if (queue_only_load >= 0 || smtp_load_reserve >= 0 || - (deliver_queue_load_max >= 0 && deliver_drop_privilege)) + (deliver_queue_load_max >= 0 && deliver_drop_privilege)) (void)os_getloadavg(); #endif @@ -1142,14 +1208,14 @@ if (background_daemon) { log_close_all(); /* Just in case anything was logged earlier */ search_tidyup(); /* Just in case any were used in reading the config. */ - close(0); /* Get rid of stdin/stdout/stderr */ - close(1); - close(2); - exim_nullstd(); /* Connect stdin/stdout/stderr to /dev/null */ + (void)close(0); /* Get rid of stdin/stdout/stderr */ + (void)close(1); + (void)close(2); + exim_nullstd(); /* Connect stdin/stdout/stderr to /dev/null */ log_stderr = NULL; /* So no attempt to copy paniclog output */ /* If the parent process of this one has pid == 1, we are re-initializing the - daemon as the result of a SIGHUP. In this case, there is no need to do + daemon as the result of a SIGHUP. In this case, there is no need to do anything, because the controlling terminal has long gone. Otherwise, fork, in case current process is a process group leader (see 'man setsid' for an explanation) before calling setsid(). */ @@ -1183,7 +1249,6 @@ if (daemon_listen) { BOOL wildcard; ip_address_item *ipa2; - int retries = 9; int af; if (Ustrchr(ipa->address, ':') != NULL) @@ -1255,19 +1320,22 @@ if (daemon_listen) { DEBUG(D_any) debug_printf("wildcard IPv4 bind() failed after IPv6 " "listen() success; EADDRINUSE ignored\n"); - close(listen_sockets[sk]); + (void)close(listen_sockets[sk]); goto SKIP_SOCKET; } msg = US strerror(errno); addr = wildcard? ((af == AF_INET6)? US"(any IPv6)" : US"(any IPv4)") : ipa->address; - if (retries-- <= 0) + if (daemon_startup_retries <= 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "socket bind() to port %d for address %s failed: %s: " "daemon abandoned", ipa->port, addr, msg); log_write(0, LOG_MAIN, "socket bind() to port %d for address %s " - "failed: %s: waiting before trying again", ipa->port, addr, msg); - sleep(30); + "failed: %s: waiting %s before trying again (%d more %s)", + ipa->port, addr, msg, readconf_printtime(daemon_startup_sleep), + daemon_startup_retries, (daemon_startup_retries > 1)? "tries" : "try"); + daemon_startup_retries--; + sleep(daemon_startup_sleep); } DEBUG(D_any) @@ -1298,7 +1366,7 @@ if (daemon_listen) DEBUG(D_any) debug_printf("wildcard IPv4 listen() failed after IPv6 " "listen() success; EADDRINUSE ignored\n"); - close(listen_sockets[sk]); + (void)close(listen_sockets[sk]); /* Come here if there has been a problem with the socket which we are going to ignore. We remove the address from the chain, and back up the @@ -1349,9 +1417,9 @@ if (running_in_test_harness || write_pid) f = Ufopen(pid_file_path, "wb"); if (f != NULL) { - fprintf(f, "%d\n", (int)getpid()); - fchmod(fileno(f), 0644); - fclose(f); + (void)fprintf(f, "%d\n", (int)getpid()); + (void)fchmod(fileno(f), 0644); + (void)fclose(f); DEBUG(D_any) debug_printf("pid written to %s\n", pid_file_path); } else @@ -1512,8 +1580,7 @@ for (;;) struct sockaddr_in accepted; #endif - SOCKLEN_T len = sizeof(accepted); - int status; + EXIM_SOCKLEN_T len = sizeof(accepted); pid_t pid; /* This code is placed first in the loop, so that it gets obeyed at the @@ -1534,19 +1601,20 @@ for (;;) if ((pid = fork()) == 0) { int sk; - + DEBUG(D_any) debug_printf("Starting queue-runner: pid %d\n", (int)getpid()); /* Disable debugging if it's required only for the daemon process. We - leave the above message, because it ties up with the "child ended" + leave the above message, because it ties up with the "child ended" debugging messages. */ if (debug_daemon) debug_selector = 0; - + /* Close any open listening sockets in the child */ - for (sk = 0; sk < listen_socket_count; sk++) close(listen_sockets[sk]); + for (sk = 0; sk < listen_socket_count; sk++) + (void)close(listen_sockets[sk]); /* Reset SIGHUP and SIGCHLD in the child in both cases. */ @@ -1622,7 +1690,7 @@ for (;;) if (daemon_listen) { - int sk, lcount; + int sk, lcount, select_errno; int max_socket = 0; BOOL select_failed = FALSE; fd_set select_listen; @@ -1635,31 +1703,42 @@ for (;;) } DEBUG(D_any) debug_printf("Listening...\n"); - - /* In rare cases we may have had a SIGCHLD signal in the time between - setting the handler (below) and getting back here. If so, pretend that the + + /* In rare cases we may have had a SIGCHLD signal in the time between + setting the handler (below) and getting back here. If so, pretend that the select() was interrupted so that we reap the child. This might still leave - a small window when a SIGCHLD could get lost. However, since we use SIGCHLD + a small window when a SIGCHLD could get lost. However, since we use SIGCHLD only to do the reaping more quickly, it shouldn't result in anything other than a delay until something else causes a wake-up. */ if (sigchld_seen) { lcount = -1; - errno = EINTR; + errno = EINTR; } else - { + { lcount = select(max_socket + 1, (SELECT_ARG2_TYPE *)&select_listen, NULL, NULL, NULL); - } + } if (lcount < 0) { select_failed = TRUE; lcount = 1; } - + + /* Clean up any subprocesses that may have terminated. We need to do this + here so that smtp_accept_max_per_host works when a connection to that host + has completed, and we are about to accept a new one. When this code was + later in the sequence, a new connection could be rejected, even though an + old one had just finished. Preserve the errno from any select() failure for + the use of the common select/accept error processing below. */ + + select_errno = errno; + handle_ending_processes(); + errno = select_errno; + /* Loop for all the sockets that are currently ready to go. If select actually failed, we have set the count to 1 and select_failed=TRUE, so as to use the common error code for select/accept below. */ @@ -1754,57 +1833,7 @@ for (;;) tv.tv_sec = queue_interval; tv.tv_usec = 0; select(0, NULL, NULL, NULL, &tv); - } - - /* Handle the termination of a child process. Theoretically, this need - be done only when sigchld_seen is TRUE, but rumour has it that some systems - lose SIGCHLD signals at busy times, so to be on the safe side, just - do it each time round. It shouldn't be too expensive. */ - - while ((pid = waitpid(-1, &status, WNOHANG)) > 0) - { - int i; - DEBUG(D_any) debug_printf("child %d ended: status=0x%x\n", (int)pid, - status); - - /* If it's a listening daemon, deal with an accepting process that has - terminated. */ - - if (daemon_listen) - { - for (i = 0; i < smtp_accept_max; i++) - { - if (smtp_slots[i].pid == pid) - { - if (smtp_slots[i].host_address != NULL) - store_free(smtp_slots[i].host_address); - smtp_slots[i] = empty_smtp_slot; - if (--smtp_accept_count < 0) smtp_accept_count = 0; - DEBUG(D_any) debug_printf("%d SMTP accept process%s now running\n", - smtp_accept_count, (smtp_accept_count == 1)? "" : "es"); - break; - } - } - if (i < smtp_accept_max) continue; /* Found an accepting process */ - } - - /* If it wasn't an accepting process, see if it was a queue-runner - process, if we are keeping track of them. */ - - if (queue_interval > 0) - { - for (i = 0; i < queue_run_max; i++) - { - if (queue_pid_slots[i] == pid) - { - queue_pid_slots[i] = 0; - if (--queue_run_count < 0) queue_run_count = 0; - DEBUG(D_any) debug_printf("%d queue-runner process%s now running\n", - queue_run_count, (queue_run_count == 1)? "" : "es"); - break; - } - } - } + handle_ending_processes(); } /* Re-enable the SIGCHLD handler if it has been run. It can't do it @@ -1829,7 +1858,8 @@ for (;;) int sk; log_write(0, LOG_MAIN, "pid %d: SIGHUP received: re-exec daemon", getpid()); - for (sk = 0; sk < listen_socket_count; sk++) close(listen_sockets[sk]); + for (sk = 0; sk < listen_socket_count; sk++) + (void)close(listen_sockets[sk]); alarm(0); signal(SIGHUP, SIG_IGN); sighup_argv[0] = exim_path;