[PATCH 4/5] log: Introduce function pointer to handle different log backends

[Torsten Hilbrich]

This allows for easier additions of other logging mechanism.
---
 src/mm-log.c | 53 ++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 34 insertions(+), 19 deletions(-)

diff --git a/src/mm-log.c b/src/mm-log.c
index bedf88f..6578d68 100644
--- a/src/mm-log.c
+++ b/src/mm-log.c
@@ -50,6 +50,12 @@ static int logfd = -1;
 static gboolean func_loc = FALSE;
 static gboolean append_log_level_text = TRUE;
 
+static void (*log_backend) (const char *loc,
+                            const char *func,
+                            int level,
+                            const char *message,
+                            size_t length);
+
 typedef struct {
     guint32 num;
     const char *name;
@@ -63,6 +69,28 @@ static const LogDesc level_descs[] = {
     { 0, NULL }
 };
 
+static void log_backend_file (const char *loc,
+                              const char *func,
+                              int level,
+                              const char *message,
+                              size_t length)
+{
+    ssize_t ign;
+    ign = write (logfd, message, length);
+    if (ign) {} /* whatever; really shut up about unused result */
+
+    fsync (logfd);  /* Make sure output is dumped to disk immediately  */
+}
+
+static void log_backend_syslog (const char *loc,
+                                const char *func,
+                                int level,
+                                const char *message,
+                                size_t length)
+{
+    syslog (level, "%s", message);
+}
+
 static GString *msgbuf = NULL;
 static volatile gsize msgbuf_once = 0;
 
@@ -129,7 +157,6 @@ _mm_log (const char *loc,
 {
     va_list args;
     GTimeVal tv;
-    ssize_t ign;
 
     if (!(log_level & level))
         return;
@@ -170,14 +197,7 @@ _mm_log (const char *loc,
 
     g_string_append_c (msgbuf, '\n');
 
-    if (logfd < 0)
-        syslog (mm_to_syslog_priority (level), "%s", msgbuf->str);
-    else {
-        ign = write (logfd, msgbuf->str, msgbuf->len);
-        if (ign) {} /* whatever; really shut up about unused result */
-
-        fsync (logfd);  /* Make sure output is dumped to disk immediately */
-    }
+    log_backend (loc, func, mm_to_syslog_priority (level), msgbuf->str, msgbuf->len);
 }
 
 static void
@@ -186,14 +206,7 @@ log_handler (const gchar *log_domain,
              const gchar *message,
              gpointer ignored)
 {
-    ssize_t ign;
-
-    if (logfd < 0)
-        syslog (glib_to_syslog_priority (level), "%s", message);
-    else {
-        ign = write (logfd, message, strlen (message));
-        if (ign) {} /* whatever; really shut up about unused result */
-    }
+    log_backend (NULL, NULL, glib_to_syslog_priority (level), message, strlen(message));
 }
 
 gboolean
@@ -247,9 +260,10 @@ mm_log_setup (const char *level,
     /* Grab start time for relative timestamps */
     g_get_current_time (&rel_start);
 
-    if (log_file == NULL)
+    if (log_file == NULL) {
         openlog (G_LOG_DOMAIN, LOG_CONS | LOG_PID | LOG_PERROR, LOG_DAEMON);
-    else {
+        log_backend = log_backend_syslog;
+    } else {
         logfd = open (log_file,
                       O_CREAT | O_APPEND | O_WRONLY,
                       S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
@@ -259,6 +273,7 @@ mm_log_setup (const char *level,
                          errno, strerror (errno));
             return FALSE;
         }
+        log_backend = log_backend_file;
     }
 
     g_log_set_handler (G_LOG_DOMAIN,
-- 
2.7.4