launch_daemon: Added basic logging facility

* The daemon now stores many events in am internal log.
* You can use "launch_roster log" to retrieve it.

src/bin/launch_roster.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2016, Axel Dörfler, [email protected].
+ * Copyright 2015-2018, Axel Dörfler, [email protected].
  * Distributed under the terms of the MIT License.
  */
 
@@ -10,11 +10,12 @@
 #include <LaunchRoster.h>
 #include <StringList.h>
 
+#include <errno.h>
 #include <getopt.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <errno.h>
+#include <time.h>
 
 
 static struct option const kLongOptions[] = {
@@ -23,6 +24,16 @@ static struct option const kLongOptions[] = {
 	{NULL}
 };
 
+static struct option const kLogLongOptions[] = {
+	{"help", no_argument, 0, 'h'},
+	{"raw", no_argument, 0, 'r'},
+	{"user", no_argument, 0, 'u'},
+	{"system", no_argument, 0, 's'},
+	{"event", required_argument, 0, 'e'},
+	{"limit", required_argument, 0, 'l'},
+	{NULL}
+};
+
 extern const char *__progname;
 static const char *kProgramName = __progname;
 
@@ -61,6 +72,127 @@ list_targets(bool verbose)
 }
 
 
+static void
+print_log(const BMessage& log)
+{
+	time_t now = time(NULL);
+	bigtime_t runtime = system_time();
+
+	for (int32 index = 0;; index++) {
+		BMessage item;
+		if (log.FindMessage("item", index, &item) != B_OK)
+			break;
+
+		uint64 when;
+		const char* message;
+		if (item.FindUInt64("when", &when) != B_OK
+			|| item.FindString("message", &message) != B_OK)
+			break;
+
+		time_t at = now - (runtime - when) / 1000000l;
+		struct tm tm;
+		localtime_r(&at, &tm);
+		char label[256];
+		strftime(label, sizeof(label), "%F %X", &tm);
+		printf("%s %s\n", label, message);
+	}
+}
+
+
+static void
+log_usage(int status)
+{
+	fprintf(stderr, "Usage: %s log [-rusel] [<job-name>]\n"
+		"Where the following options are allowed:\n"
+		"  -u --user       List only user log entries\n"
+		"  -s --system     List only system log entries\n"
+		"  -e --event      Filter by event name (partial names accepted)\n"
+		"  -l --limit <n>  Limit output to <n> events\n"
+		"<job-name>, if given, filters the jobs by name.\n",
+		kProgramName);
+
+	exit(status);
+}
+
+
+static void
+get_log(int argCount, char** args)
+{
+	bool raw = false;
+	bool userOnly = false;
+	bool systemOnly = false;
+	int32 limit = 0;
+	const char* event = NULL;
+	const char* job = NULL;
+
+	optind = 0;
+	int c;
+	while ((c = getopt_long(argCount, args, "hruse:l:", kLogLongOptions, NULL))
+			!= -1) {
+		switch (c) {
+			case 0:
+				break;
+			case 'h':
+				log_usage(0);
+				break;
+			case 'r':
+				raw = true;
+				break;
+			case 'u':
+				userOnly = true;
+				break;
+			case 's':
+				systemOnly = true;
+				break;
+			case 'e':
+				event = optarg;
+				break;
+			case 'l':
+				limit = strtol(optarg, NULL, 0);
+				break;
+		}
+	}
+
+	if (argCount - optind >= 1)
+		job = args[optind];
+
+	BLaunchRoster roster;
+	BMessage filter;
+	if (userOnly)
+		filter.AddBool("userOnly", true);
+	if (systemOnly)
+		filter.AddBool("systemOnly", true);
+	if (event != NULL)
+		filter.AddString("event", event);
+	if (job != NULL)
+		filter.AddString("job", job);
+	if (limit != 0)
+		filter.AddInt32("limit", limit);
+
+	BMessage info;
+	status_t status = roster.GetLog(filter, info);
+	if (status != B_OK) {
+		fprintf(stderr, "%s: Could not get log: %s\n", kProgramName,
+			strerror(status));
+		exit(EXIT_FAILURE);
+	}
+
+	if (raw) {
+		info.PrintToStream();
+		return;
+	}
+
+	print_log(info);
+
+	BMessage user;
+	if (info.FindMessage("user", &user) == B_OK) {
+		if (user.HasMessage("item"))
+			puts("User log:");
+		print_log(user);
+	}
+}
+
+
 static void
 get_info(const char* name)
 {
@@ -165,7 +297,7 @@ main(int argc, char** argv)
 	bool verbose = false;
 
 	int c;
-	while ((c = getopt_long(argc, argv, "hv", kLongOptions, NULL)) != -1) {
+	while ((c = getopt_long(argc, argv, "+hv", kLongOptions, NULL)) != -1) {
 		switch (c) {
 			case 0:
 				break;
@@ -188,6 +320,8 @@ main(int argc, char** argv)
 		list_jobs(verbose);
 	} else if (strcmp(command, "list-targets") == 0) {
 		list_targets(verbose);
+	} else if (strcmp(command, "log") == 0) {
+		get_log(argc - optind, &argv[optind]);
 	} else if (argc == optind + 1) {
 		// For convenience (the "info" command can be omitted)
 		get_info(command);