From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Sat, 14 Jan 2023 21:42:40 +0000 (+0200)
Subject: master: Track the last 1000 errors in a buffer
X-Git-Tag: 2.4.0~3174
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=961be3379258f08cae69ad9192498fbd62ea1a20;p=thirdparty%2Fdovecot%2Fcore.git

master: Track the last 1000 errors in a buffer

This is the same as what the log process does. The master process errors
aren't sent to the log process though.
---

diff --git a/src/master/common.h b/src/master/common.h
index 36bda94d71..f88a496910 100644
--- a/src/master/common.h
+++ b/src/master/common.h
@@ -15,6 +15,7 @@ extern bool have_proc_fs_suid_dumpable;
 extern bool have_proc_sys_kernel_core_pattern;
 extern const char *ssl_manual_key_password;
 extern int global_master_dead_pipe_fd[2];
+extern struct log_error_buffer *log_error_buffer;
 extern struct service_list *services;
 extern bool startup_finished;
 
diff --git a/src/master/main.c b/src/master/main.c
index 6c95510aaf..4cd561c900 100644
--- a/src/master/main.c
+++ b/src/master/main.c
@@ -16,6 +16,7 @@
 #include "master-instance.h"
 #include "master-service-private.h"
 #include "master-service-settings.h"
+#include "log-error-buffer.h"
 #include "askpass.h"
 #include "capabilities.h"
 #include "master-client.h"
@@ -60,6 +61,7 @@ bool have_proc_fs_suid_dumpable;
 bool have_proc_sys_kernel_core_pattern;
 const char *ssl_manual_key_password;
 int global_master_dead_pipe_fd[2];
+struct log_error_buffer *log_error_buffer;
 struct service_list *services;
 bool startup_finished = FALSE;
 
@@ -143,6 +145,25 @@ int get_gid(const char *group, gid_t *gid_r, const char **error_r)
 	}
 }
 
+static void ATTR_FORMAT(2, 0)
+master_error_handler(const struct failure_context *ctx,
+		     const char *fmt, va_list args)
+{
+	va_list args2;
+
+	VA_COPY(args2, args);
+	struct log_error error = {
+		.type = ctx->type,
+		.timestamp = ioloop_timeval,
+		.prefix = ctx->log_prefix != NULL ? ctx->log_prefix : "",
+		.text = t_strdup_vprintf(fmt, args2),
+	};
+	log_error_buffer_add(log_error_buffer, &error);
+	va_end(args2);
+
+	orig_error_callback(ctx, fmt, args);
+}
+
 static void ATTR_NORETURN ATTR_FORMAT(2, 0)
 master_fatal_callback(const struct failure_context *ctx,
 		      const char *format, va_list args)
@@ -594,6 +615,9 @@ static void main_deinit(void)
 	service_pids_deinit();
 	/* notify systemd that we are done */
 	i_sd_notify(0, "STATUS=Dovecot stopped");
+
+	i_set_error_handler(orig_error_callback);
+	log_error_buffer_deinit(&log_error_buffer);
 }
 
 static const char *get_full_config_path(struct service_list *list)
@@ -909,8 +933,9 @@ int main(int argc, char *argv[])
 	if (chdir(set->base_dir) < 0)
 		i_fatal("chdir(%s) failed: %m", set->base_dir);
 
+	log_error_buffer = log_error_buffer_init();
 	i_set_fatal_handler(master_fatal_callback);
-	i_set_error_handler(orig_error_callback);
+	i_set_error_handler(master_error_handler);
 
 	if (!foreground)
 		daemonize();
diff --git a/src/master/master-client.c b/src/master/master-client.c
index 6294b28112..014d21eed8 100644
--- a/src/master/master-client.c
+++ b/src/master/master-client.c
@@ -6,6 +6,7 @@
 #include "strescape.h"
 #include "ostream.h"
 #include "connection.h"
+#include "log-error-buffer.h"
 #include "service.h"
 #include "service-process.h"
 #include "service-monitor.h"
@@ -83,6 +84,35 @@ master_client_process_status(struct master_client *client,
 	return 1;
 }
 
+static int master_client_send_errors(struct master_client *client)
+{
+	struct log_error_buffer_iter *iter;
+	const struct log_error *error;
+	string_t *str = t_str_new(256);
+	int ret = 0;
+
+	iter = log_error_buffer_iter_init(log_error_buffer);
+	while ((error = log_error_buffer_iter_next(iter)) != NULL) {
+		str_truncate(str, 0);
+		str_printfa(str, "%s\t%"PRIdTIME_T".%06u\t",
+			    failure_log_type_names[error->type],
+			    error->timestamp.tv_sec,
+			    (unsigned int)error->timestamp.tv_usec);
+		str_append_tabescaped(str, error->prefix);
+		str_append_c(str, '\t');
+		str_append_tabescaped(str, error->text);
+		str_append_c(str, '\n');
+		if (o_stream_send(client->conn.output,
+				  str_data(str), str_len(str)) < 0) {
+			ret = -1;
+			break;
+		}
+	}
+	log_error_buffer_iter_deinit(&iter);
+	o_stream_nsend_str(client->conn.output, "\n");
+	return ret;
+}
+
 static int
 master_client_stop(struct master_client *client, const char *const *args)
 {
@@ -118,6 +148,8 @@ master_client_input_args(struct connection *conn, const char *const *args)
 		return master_client_service_status(client);
 	if (strcmp(cmd, "PROCESS-STATUS") == 0)
 		return master_client_process_status(client, args);
+	if (strcmp(cmd, "ERROR-LOG") == 0)
+		return master_client_send_errors(client);
 	if (strcmp(cmd, "STOP") == 0)
 		return master_client_stop(client, args);
 	e_error(conn->event, "Unknown command: %s", cmd);