From ea9bc5326117d80855bd083e77130e3263b6ed5d Mon Sep 17 00:00:00 2001
From: Cloud Wu <cloudwu@gmail.com>
Date: Sun, 12 Jun 2016 13:40:23 +0800
Subject: [PATCH] reopen log file when recv signal HUP

---
 service-src/service_logger.c | 28 ++++++++++++++++++++++------
 skynet-src/skynet_start.c    | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 6 deletions(-)

diff --git a/service-src/service_logger.c b/service-src/service_logger.c
index 122cc77f..e73300e3 100644
--- a/service-src/service_logger.c
+++ b/service-src/service_logger.c
@@ -3,9 +3,11 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
+#include <string.h>
 
 struct logger {
 	FILE * handle;
+	char * filename;
 	int close;
 };
 
@@ -14,6 +16,8 @@ logger_create(void) {
 	struct logger * inst = skynet_malloc(sizeof(*inst));
 	inst->handle = NULL;
 	inst->close = 0;
+	inst->filename = NULL;
+
 	return inst;
 }
 
@@ -22,16 +26,26 @@ logger_release(struct logger * inst) {
 	if (inst->close) {
 		fclose(inst->handle);
 	}
+	skynet_free(inst->filename);
 	skynet_free(inst);
 }
 
 static int
-_logger(struct skynet_context * context, void *ud, int type, int session, uint32_t source, const void * msg, size_t sz) {
+logger_cb(struct skynet_context * context, void *ud, int type, int session, uint32_t source, const void * msg, size_t sz) {
 	struct logger * inst = ud;
-	fprintf(inst->handle, "[:%08x] ",source);
-	fwrite(msg, sz , 1, inst->handle);
-	fprintf(inst->handle, "\n");
-	fflush(inst->handle);
+	switch (type) {
+	case PTYPE_SYSTEM:
+		if (inst->filename) {
+			inst->handle = freopen(inst->filename, "a", inst->handle);
+		}
+		break;
+	case PTYPE_TEXT:
+		fprintf(inst->handle, "[:%08x] ",source);
+		fwrite(msg, sz , 1, inst->handle);
+		fprintf(inst->handle, "\n");
+		fflush(inst->handle);
+		break;
+	}
 
 	return 0;
 }
@@ -43,12 +57,14 @@ logger_init(struct logger * inst, struct skynet_context *ctx, const char * parm)
 		if (inst->handle == NULL) {
 			return 1;
 		}
+		inst->filename = skynet_malloc(strlen(parm)+1);
+		strcpy(inst->filename, parm);
 		inst->close = 1;
 	} else {
 		inst->handle = stdout;
 	}
 	if (inst->handle) {
-		skynet_callback(ctx, inst, _logger);
+		skynet_callback(ctx, inst, logger_cb);
 		skynet_command(ctx, "REG", ".logger");
 		return 0;
 	}
diff --git a/skynet-src/skynet_start.c b/skynet-src/skynet_start.c
index 5345c76c..a7b1d70b 100644
--- a/skynet-src/skynet_start.c
+++ b/skynet-src/skynet_start.c
@@ -16,6 +16,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <signal.h>
 
 struct monitor {
 	int count;
@@ -32,6 +33,15 @@ struct worker_parm {
 	int weight;
 };
 
+static int SIG = 0;
+
+static void
+handle_hup(int signal) {
+	if (signal == SIGHUP) {
+		SIG = 1;
+	}
+}
+
 #define CHECK_ABORT if (skynet_context_total()==0) break;
 
 static void
@@ -100,6 +110,21 @@ thread_monitor(void *p) {
 	return NULL;
 }
 
+static void
+signal_hup() {
+	// make log file reopen
+
+	struct skynet_message smsg;
+	smsg.source = 0;
+	smsg.session = 0;
+	smsg.data = NULL;
+	smsg.sz = (size_t)PTYPE_SYSTEM << MESSAGE_TYPE_SHIFT;
+	uint32_t logger = skynet_handle_findname("logger");
+	if (logger) {
+		skynet_context_push(logger, &smsg);
+	}
+}
+
 static void *
 thread_timer(void *p) {
 	struct monitor * m = p;
@@ -109,6 +134,10 @@ thread_timer(void *p) {
 		CHECK_ABORT
 		wakeup(m,m->count-1);
 		usleep(2500);
+		if (SIG) {
+			signal_hup();
+			SIG = 0;
+		}
 	}
 	// wakeup socket thread
 	skynet_socket_exit();
@@ -216,6 +245,13 @@ bootstrap(struct skynet_context * logger, const char * cmdline) {
 
 void 
 skynet_start(struct skynet_config * config) {
+	// register SIGHUP for log file reopen
+	struct sigaction sa;
+	sa.sa_handler = &handle_hup;
+	sa.sa_flags = SA_RESTART;
+	sigfillset(&sa.sa_mask);
+	sigaction(SIGHUP, &sa, NULL);
+
 	if (config->daemon) {
 		if (daemon_init(config->daemon)) {
 			exit(1);