Keep track of bytes written to a file

src/logging.c

@@ -34,6 +34,7 @@ struct UCLogDestination {
         struct {
             FILE* file; 
             char *file_name; //NULL for stderr destinaton
+            size_t size; //keeps track of no of bytes written
         } file;
     } type;
 };
@@ -161,6 +162,7 @@ struct UCLogDestination *uc_log_new_stderr(int log_level, int log_location)
     
     dest->dest_type = UC_LDEST_STDERR;
     dest->type.file.file = stderr;
+    dest->type.file.size = 0;
     dest->log_level = log_level;;
     dest->log_location = log_location;
 
@@ -233,6 +235,7 @@ struct UCLogDestination *uc_log_new_file(const char *filename, int log_level, in
     dest->dest_type = UC_LDEST_FILE;
     dest->type.file.file = f;
     dest->type.file.file_name = name;
+    dest->type.file.size = 0;
     dest->log_level = log_level;;
     dest->log_location = log_location;
 
@@ -387,6 +390,7 @@ int uc_log_reopen_files(void)
 
         if (dest->dest_type == UC_LDEST_FILE) {
             rc = uc_log_reopen_file(dest);
+            dest->type.file.size = 0;
         }
     }
 
@@ -407,6 +411,7 @@ static inline void uc_vlog_file(const struct UCLogArgs *args, const char *fmt, v
     char time_buf[48];
     time_t now;
     struct tm t;
+    int rc;
 
     if (dest->type.file.file == NULL)
         return;
@@ -425,20 +430,25 @@ static inline void uc_vlog_file(const struct UCLogArgs *args, const char *fmt, v
         time_buf[sizeof time_buf -1] = 0;
 
         if (dest->log_location) {
-            fprintf(dest->type.file.file, "[%-7s] %s %s [%s] : ", 
+            rc = fprintf(dest->type.file.file, "[%-7s] %s %s [%s] : ", 
                     uc_ll_2_str(args->log_level), time_buf, 
                     args->location, args->module->short_name);
         } else {
-            fprintf(dest->type.file.file, "[%-7s] %s [%s]: ", 
+            rc = fprintf(dest->type.file.file, "[%-7s] %s [%s]: ", 
                 uc_ll_2_str(args->log_level), time_buf, args->module->short_name);
         }
     }
 
+    if (rc >= 0) {
+        dest->type.file.size += rc;
+        rc = vfprintf(dest->type.file.file, fmt, ap);
+    }
 
-    vfprintf(dest->type.file.file, fmt, ap);
-
-    fflush(dest->type.file.file); //strictly not needed for stderr
+    if (rc >= 0) {
+        dest->type.file.size += rc;
+        rc = fflush(dest->type.file.file); //strictly not needed for stderr
                                            // though stderr could be redirected to a file
+    }
 }
 
 static inline void uc_vlog_syslog(const struct UCLogArgs *args, const char *fmt, va_list ap)