From e1cbe753babe180cb22cf504e3a1f3a55000a46c Mon Sep 17 00:00:00 2001
From: yuqing <yuqing@yongche.com>
Date: Thu, 7 Aug 2014 14:18:14 +0800
Subject: [PATCH] logger can take over stderr and stdout

---
 src/logger.c | 42 ++++++++++++++++++++++++++++++++++++++++--
 src/logger.h | 24 ++++++++++++++++++++++++
 2 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/src/logger.c b/src/logger.c
index 261b806..38a5480 100644
--- a/src/logger.c
+++ b/src/logger.c
@@ -63,6 +63,18 @@ int log_init()
 	return log_init_ex(&g_log_context);
 }
 
+int log_init2()
+{
+    int result;
+    if ((result=log_init()) != 0) {
+        return result;
+    }
+
+    log_take_over_stderr();
+    log_take_over_stdout();
+    return 0;
+}
+
 int log_init_ex(LogContext *pContext)
 {
 	int result;
@@ -97,17 +109,33 @@ static int log_open(LogContext *pContext)
 				O_CREAT | O_APPEND, 0644)) < 0)
 	{
 		fprintf(stderr, "open log file \"%s\" to write fail, " \
-			"errno: %d, error info: %s", \
+			"errno: %d, error info: %s\n", \
 			pContext->log_filename, errno, STRERROR(errno));
 		pContext->log_fd = STDERR_FILENO;
 		return errno != 0 ? errno : EACCES;
 	}
 
+    if (pContext->take_over_stderr) {
+        if (dup2(pContext->log_fd, STDERR_FILENO) < 0) {
+            fprintf(stderr, "file: "__FILE__", line: %d, "
+                    "call dup2 fail, errno: %d, error info: %s\n",
+                    __LINE__, errno, STRERROR(errno));
+        }
+    }
+
+    if (pContext->take_over_stdout) {
+        if (dup2(pContext->log_fd, STDOUT_FILENO) < 0) {
+            fprintf(stderr, "file: "__FILE__", line: %d, "
+                    "call dup2 fail, errno: %d, error info: %s\n",
+                    __LINE__, errno, STRERROR(errno));
+        }
+    }
+
 	pContext->current_size = lseek(pContext->log_fd, 0, SEEK_END);
 	if (pContext->current_size < 0)
 	{
 		fprintf(stderr, "lseek file \"%s\" fail, " \
-			"errno: %d, error info: %s", \
+			"errno: %d, error info: %s\n", \
 			pContext->log_filename, errno, STRERROR(errno));
 		return errno != 0 ? errno : EACCES;
 	}
@@ -182,6 +210,16 @@ void log_set_header_callback(LogContext *pContext, LogHeaderCallback header_call
     }
 }
 
+void log_take_over_stderr_ex(LogContext *pContext)
+{
+    pContext->take_over_stderr = true;
+}
+
+void log_take_over_stdout_ex(LogContext *pContext)
+{
+    pContext->take_over_stdout = true;
+}
+
 void log_destroy_ex(LogContext *pContext)
 {
 	if (pContext->log_fd >= 0 && pContext->log_fd != STDERR_FILENO)
diff --git a/src/logger.h b/src/logger.h
index 48050e0..cf5ed8e 100644
--- a/src/logger.h
+++ b/src/logger.h
@@ -61,6 +61,12 @@ typedef struct log_context
 	/* if rotate the access log */
 	bool rotate_immediately;
 
+	/* if stderr to the log file */
+    bool take_over_stderr;
+
+	/* if stdout to the log file */
+    bool take_over_stdout;
+
 	/* time precision */
 	char time_precision;
 
@@ -88,6 +94,11 @@ extern LogContext g_log_context;
 */
 int log_init();
 
+/** init function using global log context, take over stderr and stdout
+ *  return: 0 for success, != 0 fail
+*/
+int log_init2();
+
 #define log_set_prefix(base_path, filename_prefix) \
 	log_set_prefix_ex(&g_log_context, base_path, filename_prefix)
 
@@ -96,6 +107,9 @@ int log_init();
 
 #define log_set_cache(bLogCache)  log_set_cache_ex(&g_log_context, bLogCache)
 
+#define log_take_over_stderr()  log_take_over_stderr_ex(&g_log_context)
+#define log_take_over_stdout()  log_take_over_stdout_ex(&g_log_context)
+
 #define log_destroy()  log_destroy_ex(&g_log_context)
 
 /** init function, use stderr for output by default
@@ -164,6 +178,16 @@ void log_set_keep_days(LogContext *pContext, const int keep_days);
 */
 void log_set_header_callback(LogContext *pContext, LogHeaderCallback header_callback);
 
+/** set take_over_stderr to true
+ *  return: none
+*/
+void log_take_over_stderr_ex(LogContext *pContext);
+
+/** set take_over_stdout to true
+ *  return: none
+*/
+void log_take_over_stdout_ex(LogContext *pContext);
+
 /** destroy function
  *  parameters:
  *           pContext: the log context