core/say: Export logger fd

We need it inside popen engine to be able to print
errors from inside of a child process.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

src/lib/core/say.c

@@ -168,6 +168,12 @@ log_type()
 	return log_default->type;
 }
 
+int
+log_get_fd(void)
+{
+	return log_default->fd;
+}
+
 void
 log_set_level(struct log *log, enum say_level level)
 {

src/lib/core/say.h

@@ -144,6 +144,7 @@ typedef int (*log_format_func_t)(struct log *log, char *buf, int len, int level,
  * A log object. There is a singleton for the default log.
  */
 struct log {
+	/** The current file descriptor. */
 	int fd;
 	/** The current log level. */
 	int level;
@@ -202,6 +203,12 @@ log_say(struct log *log, int level, const char *filename,
 enum say_logger_type
 log_type();
 
+/**
+ * Default logger file descriptor.
+ */
+int
+log_get_fd(void);
+
 /**
  * Set log level. Can be used dynamically.
  *