refactor(log,conf): initialize log without conf file and installation…

… directory

Especially for the case where the installation directory does not exist during CMake installation.

docs/Melon Developer Guide.txt

@@ -906,6 +906,9 @@ Their definitions can be found in melon/include/mln_types.h.
      f) void mln_conf_hook_unset(mln_conf_hook_t *hook);
         This interface is used to unset a callback function which has been set in the global reload chain.
 
+     g) mln_conf_is_empty(cf);
+        Check if the configuration is empty.
+
   11) Event
      Just like libevent, Melon's event module also integrates epoll, kqueue and select.
      It supports three kinds of event: timer event, signal event and file descriptor event.

docs/book/cn/conf.md

@@ -293,6 +293,21 @@ mln_u32_t mln_conf_arg_num(mln_conf_cmd_t *cc);
 
 
 
+#### mln_conf_is_empty
+
+```c
+mln_conf_is_empty(cf);
+```
+
+描述：检查配置是否为空。
+
+返回值：
+
+- `0` - 非空
+- `非0` - 空
+
+
+
 ### 示例
 
 ```c

docs/book/cn/log.md

@@ -140,6 +140,7 @@ mln_logger_t mln_log_logger_get(void);
 int main(int argc, char *argv[])
 {
     mln_log(debug, "This will be outputted to stderr\n");
+    mln_conf_load();
     mln_log_init(NULL);
     mln_log(debug, "This will be outputted to stderr and log file\n");
     return 0;

docs/book/en/conf.md

@@ -291,6 +291,21 @@ Return value: the number of command item parameters
 
 
 
+#### mln_conf_is_empty
+
+```c
+mln_conf_is_empty(cf);
+```
+
+Description: Check if the configuration is empty.
+
+Return values:
+
+- `0` - Not empty
+- `Non-zero` - Empty
+
+
+
 ### Example
 
 ```c

docs/book/en/log.md

@@ -140,6 +140,7 @@ Return value: Returns the current log processing function pointer
 int main(int argc, char *argv[])
 {
     mln_log(debug, "This will be outputted to stderr\n");
+    mln_conf_load();
     mln_log_init(NULL);
     mln_log(debug, "This will be outputted to stderr and log file\n");
     return 0;

include/mln_conf.h

@@ -86,6 +86,11 @@ typedef struct mln_conf_hook_s {
 /*
  * mln_conf_load should be called before any pthread_create
  */
+
+#define mln_conf_is_empty(cf) ((cf) == NULL || \
+    (mln_rbtree_node_num((cf)->domain) <= 1 && \
+    mln_rbtree_node_num(((mln_conf_domain_t *)(mln_rbtree_node_data_get(mln_rbtree_root((cf)->domain))))->cmd) == 0))
+
 extern int mln_conf_load(void);
 extern int mln_conf_reload(void);
 extern void mln_conf_free(void);

src/mln_conf.c

@@ -377,7 +377,7 @@ static inline mln_conf_t *mln_conf_init(void)
             return NULL;
         }
     } else {
-        fprintf(stderr, "[Warn] Configuration file [%s] not found.\n", conf_file_path);
+        fprintf(stderr, "[Warn] Configuration file [%s] not found, default configuration will be used.\n", conf_file_path);
         cf->lex = NULL;
     }
 

src/mln_log.c

@@ -102,39 +102,37 @@ mln_logger_t mln_log_logger_get(void)
  */
 int mln_log_init(mln_conf_t *cf)
 {
-    mln_u32_t in_daemon = 0;
+    mln_u32_t in_daemon = 0, init = 0;
     mln_conf_domain_t *cd;
     mln_conf_cmd_t *cc;
     mln_conf_item_t *ci;
     mln_log_t *log = &g_log;
     if (log->init) return 0;
 
-    if (cf == NULL) {
-        if (mln_conf_load() < 0) {
-            fprintf(stderr, "load configuration failed.\n");
+    if (cf == NULL) cf = mln_conf();
+    if (mln_conf_is_empty(cf))
+        fprintf(stdout, "[WARN] Load configuration failed. Logger won't be initialized.\n");
+    else {
+        if ((cd = cf->search(cf, "main")) == NULL) {
+            fprintf(stderr, "No such domain named 'main'\n");
             return -1;
         }
-        cf = mln_conf();
-    }
-
-    if ((cd = cf->search(cf, "main")) == NULL) {
-        fprintf(stderr, "No such domain named 'main'\n");
-        return -1;
-    }
-    if ((cc = cd->search(cd, "daemon")) != NULL) {
-        if ((ci = cc->search(cc, 1)) == NULL) {
-            fprintf(stderr, "Command 'daemon' need a parameter.\n");
-            return -1;
-        }
-        if (ci->type != CONF_BOOL) {
-            fprintf(stderr, "Parameter type of command 'daemon' error.\n");
-            return -1;
+        if ((cc = cd->search(cd, "daemon")) != NULL) {
+            if ((ci = cc->search(cc, 1)) == NULL) {
+                fprintf(stderr, "Command 'daemon' need a parameter.\n");
+                return -1;
+            }
+            if (ci->type != CONF_BOOL) {
+                fprintf(stderr, "Parameter type of command 'daemon' error.\n");
+                return -1;
+            }
+            if (ci->val.b) in_daemon = 1;
         }
-        if (ci->val.b) in_daemon = 1;
+        init = 1;
     }
 
     log->in_daemon = in_daemon;
-    log->init = 1;
+    log->init = init;
     log->level = none;
     int ret = 0;
 #if !defined(MSVC)
@@ -169,7 +167,7 @@ int mln_log_init(mln_conf_t *cf)
 static int
 mln_log_get_log(mln_log_t *log, mln_conf_t *cf, int is_init)
 {
-    if (cf == NULL) return -1;
+    if (mln_conf_is_empty(cf)) return 0;
 
     mln_conf_domain_t *cd;
     mln_conf_cmd_t *cc;
@@ -314,7 +312,7 @@ void mln_log_destroy(void)
  */
 static int mln_log_set_level(mln_log_t *log, mln_conf_t *cf, int is_init)
 {
-    if (cf == NULL) return 0;
+    if (mln_conf_is_empty(cf)) return 0;
 
     mln_conf_domain_t *cd = cf->search(cf, "main");
     if (cd == NULL) {

t/log.c

@@ -4,6 +4,7 @@
 int main(int argc, char *argv[])
 {
     mln_log(debug, "This will be outputted to stderr\n");
+    mln_conf_load();
     assert(mln_log_init(NULL) == 0);
     mln_log(debug, "This will be outputted to stderr and log file\n");
     mln_log_destroy();