X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=server.c;h=a4115eb65734391128481f6fa421d548aba78e20;hp=287b628b0d2e7ffee18886f8885f58882d6e155a;hb=ad81d625737e1c096c154aedd8a1d161d3ee592e;hpb=cf3c87c56287ce84e0bb10ea8866294578ede489

diff --git a/server.c b/server.c
index 287b628b..a4115eb6 100644
--- a/server.c
+++ b/server.c
@@ -85,6 +85,7 @@
 #include "sched.h"
 #include "signal.h"
 #include "user_list.h"
+#include "color.h"
 
 /** Define the array of error lists needed by para_server. */
 INIT_SERVER_ERRLISTS;
@@ -112,11 +113,8 @@ uint32_t afs_socket_cookie;
 /** The mutex protecting the shared memory area containing the mmd struct. */
 int mmd_mutex;
 
-/* global variables for server-internal use */
-static FILE *logfile;
 /** The file containing user information (public key, permissions). */
 static char *user_list_file = NULL;
-static int mmd_shm_id;
 
 
 /** The task responsible for server command handling. */
@@ -131,54 +129,48 @@ struct server_command_task {
 	struct task task;
 };
 
-/**
- * Para_server's log function.
- *
- * \param ll The log level.
- * \param fmt The format string describing the log message.
- */
-__printf_2_3 void para_log(int ll, const char* fmt,...)
+static int want_colors(void)
 {
-	va_list argp;
-	FILE *outfd;
-	struct tm *tm;
-	time_t t1;
-	char str[MAXLINE] = "";
-	pid_t mypid;
-
-	if (ll < conf.loglevel_arg)
+	if (conf.color_arg == color_arg_no)
+		return 0;
+	if (conf.color_arg == color_arg_yes)
+		return 1;
+	if (conf.logfile_given)
+		return 0;
+	return isatty(STDERR_FILENO);
+}
+
+static void init_colors_or_die(void)
+{
+	int ret, i;
+
+	if (!want_colors())
 		return;
-	outfd = logfile? logfile : stderr;
-	time(&t1);
-	tm = localtime(&t1);
-	strftime(str, MAXLINE, "%b %d %H:%M:%S", tm);
-	fprintf(outfd, "%s ", str);
-	if (conf.loglevel_arg <= INFO)
-		fprintf(outfd, "%i: ", ll);
-	mypid = getpid();
-	if (conf.loglevel_arg <= INFO)
-		fprintf(outfd, "(%d) ", (int)mypid);
-	va_start(argp, fmt);
-	vfprintf(outfd, fmt, argp);
-	va_end(argp);
+	daemon_set_flag(DF_COLOR_LOG);
+	daemon_set_default_log_colors();
+	for (i = 0; i < conf.log_color_given; i++) {
+		ret = daemon_set_log_color(conf.log_color_arg[i]);
+		if (ret < 0)
+			exit(EXIT_FAILURE);
+	}
 }
 
 /*
  * setup shared memory area and get mutex for locking
  */
-static void shm_init(void)
+static void init_ipc_or_die(void)
 {
 	void *shm;
-	int ret = shm_new(sizeof(struct misc_meta_data));
+	int shmid, ret = shm_new(sizeof(struct misc_meta_data));
 
 	if (ret < 0)
 		goto err_out;
-
-	ret = shm_attach(ret, ATTACH_RW, &shm);
+	shmid = ret;
+	ret = shm_attach(shmid, ATTACH_RW, &shm);
+	shm_destroy(shmid);
 	if (ret < 0)
 		goto err_out;
 	mmd = shm;
-	mmd_shm_id = ret;
 
 	ret = mutex_new();
 	if (ret < 0)
@@ -198,13 +190,21 @@ err_out:
 	exit(EXIT_FAILURE);
 }
 
-static void parse_config(int override)
+/**
+ * (Re-)read the server configuration files.
+ *
+ * \param override Passed to gengetopt to activate the override feature.
+ *
+ * This function also re-opens the logfile and sets the global \a
+ * user_list_file variable.
+ */
+void parse_config_or_die(int override)
 {
 	char *home = para_homedir();
-	struct stat statbuf;
 	int ret;
 	char *cf;
 
+	daemon_close_log();
 	if (conf.config_file_given)
 		cf = para_strdup(conf.config_file_arg);
 	else
@@ -214,26 +214,33 @@ static void parse_config(int override)
 		user_list_file = make_message("%s/.paraslash/server.users", home);
 	else
 		user_list_file = para_strdup(conf.user_list_arg);
-	ret = stat(cf, &statbuf);
-	if (ret && conf.config_file_given) {
+	ret = file_exists(cf);
+	if (conf.config_file_given && !ret)  {
 		ret = -1;
-		PARA_EMERG_LOG("can not stat config file %s\n", cf);
+		PARA_EMERG_LOG("can not read config file %s\n", cf);
 		goto out;
 	}
-	if (!ret) {
+	if (ret) {
 		int tmp = conf.daemon_given;
 		struct server_cmdline_parser_params params = {
 			.override = override,
 			.initialize = 0,
 			.check_required = 1,
 			.check_ambiguity = 0,
-			.print_errors = 1
+			.print_errors = !conf.daemon_given
 		};
 		server_cmdline_parser_config_file(cf, &conf, &params);
 		conf.daemon_given = tmp;
 	}
-	if (conf.logfile_given)
-		logfile = open_log(conf.logfile_arg);
+	if (conf.logfile_given) {
+		daemon_set_logfile(conf.logfile_arg);
+		daemon_open_log_or_die();
+	}
+	daemon_set_loglevel(conf.loglevel_arg);
+	init_colors_or_die();
+	daemon_set_flag(DF_LOG_PID);
+	daemon_set_flag(DF_LOG_LL);
+	daemon_set_flag(DF_LOG_TIME);
 	ret = 1;
 out:
 	free(cf);
@@ -257,9 +264,7 @@ static void signal_pre_select(struct sched *s, struct task *t)
 static void handle_sighup(void)
 {
 	PARA_NOTICE_LOG("SIGHUP\n");
-	close_log(logfile); /* gets reopened if necessary by parse_config */
-	logfile = NULL;
-	parse_config(1); /* reopens log */
+	parse_config_or_die(1); /* reopens log */
 	init_user_list(user_list_file); /* reload user list */
 	if (mmd->afs_pid)
 		kill(mmd->afs_pid, SIGHUP);
@@ -295,10 +300,11 @@ static void signal_post_select(struct sched *s, struct task *t)
 		PARA_EMERG_LOG("terminating on signal %d\n", st->signum);
 genocide:
 		kill(0, SIGTERM);
+		free(mmd->afd.afhi.chunk_table);
+		free(mmd->afd.afhi.info_string);
+		close_listed_fds();
 		mutex_destroy(mmd_mutex);
 		shm_detach(mmd);
-		shm_destroy(mmd_shm_id);
-
 		exit(EXIT_FAILURE);
 	}
 }
@@ -325,8 +331,6 @@ static void init_signal_task(void)
 		goto err;
 	if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
 		goto err;
-	if (signal(SIGUSR1, SIG_IGN) == SIG_ERR)
-		goto err;
 	add_close_on_fork_list(st->fd);
 	register_task(&st->task);
 	return;
@@ -348,6 +352,8 @@ static void command_post_select(struct sched *s, struct task *t)
 	int new_fd, ret, i;
 	char *peer_name;
 	pid_t child_pid;
+	uint32_t *chunk_table;
+	char *info_string;
 
 	if (!FD_ISSET(sct->listen_fd, &s->rfds))
 		return;
@@ -360,6 +366,16 @@ static void command_post_select(struct sched *s, struct task *t)
 	mmd->num_connects++;
 	mmd->active_connections++;
 	random();
+	/* The chunk table and the info_string are pointers located in the
+	 * mmd struct that point to dynamically allocated memory that must be
+	 * freed by the parent and the child. However, as the mmd struct is in
+	 * a shared memory area, there's no guarantee that after the fork these
+	 * pointers are still valid in child context. As these two pointers are
+	 * not used in the child anyway, we save them to local variables and
+	 * free the memory via that copy in the child.
+	 */
+	info_string = mmd->afd.afhi.info_string;
+	chunk_table = mmd->afd.afhi.chunk_table;
 	child_pid = fork();
 	if (child_pid < 0) {
 		ret = -ERRNO_TO_PARA_ERROR(errno);
@@ -370,6 +386,9 @@ static void command_post_select(struct sched *s, struct task *t)
 		/* parent keeps accepting connections */
 		return;
 	}
+	/* mmd might already have changed at this point */
+	free(info_string);
+	free(chunk_table);
 	alarm(ALARM_TIMEOUT);
 	close_listed_fds();
 	para_signal_shutdown();
@@ -466,6 +485,12 @@ static int init_afs(void)
 	return afs_server_socket[0];
 }
 
+__noreturn static void tmp_sigchld_handler(__a_unused int s)
+{
+	PARA_EMERG_LOG("caught early SIGCHLD\n");
+	exit(EXIT_FAILURE);
+}
+
 static void server_init(int argc, char **argv)
 {
 	struct server_cmdline_parser_params params = {
@@ -482,20 +507,41 @@ static void server_init(int argc, char **argv)
 	/* parse command line options */
 	server_cmdline_parser_ext(argc, argv, &conf, &params);
 	HANDLE_VERSION_FLAG("server", conf);
-	para_drop_privileges(conf.user_arg, conf.group_arg);
+	drop_privileges_or_die(conf.user_arg, conf.group_arg);
 	/* parse config file, open log and set defaults */
-	parse_config(0);
-	log_welcome("para_server", conf.loglevel_arg);
-	shm_init(); /* init mmd struct */
+	parse_config_or_die(0);
+	log_welcome("para_server");
+	init_ipc_or_die(); /* init mmd struct and mmd->lock */
 	/* make sure, the global now pointer is uptodate */
 	gettimeofday(now, NULL);
 	server_uptime(UPTIME_SET); /* reset server uptime */
 	init_user_list(user_list_file);
 	/* become daemon */
 	if (conf.daemon_given)
-		daemon_init();
+		daemonize();
 	PARA_NOTICE_LOG("initializing audio format handlers\n");
 	afh_init();
+
+	/*
+	 * Although afs uses its own signal handling we must ignore SIGUSR1
+	 * _before_ the afs child process gets born by init_afs() below.  It's
+	 * racy to do this in the child because the parent might send SIGUSR1
+	 * before the child gets a chance to ignore this signal -- only the
+	 * good die young.
+	 */
+	if (signal(SIGUSR1, SIG_IGN) == SIG_ERR) {
+		PARA_EMERG_LOG("failed to ignore SIGUSR1\n");
+		exit(EXIT_FAILURE);
+	}
+	/*
+	 * We have to install a SIGCHLD handler before the afs process is being
+	 * forked off. Otherwise, para_server does not notice if afs dies before
+	 * the SIGCHLD handler has been installed by init_signal_task() below.
+	 */
+	if (signal(SIGCHLD, tmp_sigchld_handler) == SIG_ERR) {
+		PARA_EMERG_LOG("failed to install temporary SIGCHLD handler\n");
+		exit(EXIT_FAILURE);
+	}
 	PARA_NOTICE_LOG("initializing the audio file selector\n");
 	afs_socket = init_afs();
 	init_signal_task();