wpa_supplicant: Support 'relog' command to re-open log files

This allows rolling log files:

mv log.txt log.txt.1
wpa_cli relog

Signed-off-by: Ben Greear <greearb@candelatech.com>

src/utils/wpa_debug.c

@@ -273,11 +273,43 @@ void wpa_hexdump_ascii_key(int level, const char *title, const u8 *buf,
 }
 
 
+#ifdef CONFIG_DEBUG_FILE
+static char *last_path = NULL;
+#endif /* CONFIG_DEBUG_FILE */
+
+int wpa_debug_reopen_file(void)
+{
+#ifdef CONFIG_DEBUG_FILE
+	int rv;
+	if (last_path) {
+		char *tmp = os_strdup(last_path);
+		wpa_debug_close_file();
+		rv = wpa_debug_open_file(tmp);
+		os_free(tmp);
+	} else {
+		wpa_printf(MSG_ERROR, "Last-path was not set, cannot "
+			   "re-open log file.");
+		rv = -1;
+	}
+	return rv;
+#else /* CONFIG_DEBUG_FILE */
+	return 0;
+#endif /* CONFIG_DEBUG_FILE */
+}
+
+
 int wpa_debug_open_file(const char *path)
 {
 #ifdef CONFIG_DEBUG_FILE
 	if (!path)
 		return 0;
+
+	if (last_path == NULL || os_strcmp(last_path, path) != 0) {
+		/* Save our path to enable re-open */
+		os_free(last_path);
+		last_path = os_strdup(path);
+	}
+
 	out_file = fopen(path, "a");
 	if (out_file == NULL) {
 		wpa_printf(MSG_ERROR, "wpa_debug_open_file: Failed to open "
@@ -299,6 +331,8 @@ void wpa_debug_close_file(void)
 		return;
 	fclose(out_file);
 	out_file = NULL;
+	os_free(last_path);
+	last_path = NULL;
 #endif /* CONFIG_DEBUG_FILE */
 }
 

src/utils/wpa_debug.h

@@ -40,6 +40,7 @@ enum {
 #else /* CONFIG_NO_STDOUT_DEBUG */
 
 int wpa_debug_open_file(const char *path);
+int wpa_debug_reopen_file(void);
 void wpa_debug_close_file(void);
 
 /**

wpa_supplicant/ctrl_iface.c

@@ -2785,6 +2785,9 @@ char * wpa_supplicant_ctrl_iface_process(struct wpa_supplicant *wpa_s,
 	if (os_strcmp(buf, "PING") == 0) {
 		os_memcpy(reply, "PONG\n", 5);
 		reply_len = 5;
+	} else if (os_strncmp(buf, "RELOG", 5) == 0) {
+		if (wpa_debug_reopen_file() < 0)
+			reply_len = -1;
 	} else if (os_strncmp(buf, "NOTE ", 5) == 0) {
 		wpa_printf(MSG_INFO, "NOTE: %s", buf + 5);
 	} else if (os_strcmp(buf, "MIB") == 0) {

wpa_supplicant/wpa_cli.c

@@ -278,6 +278,12 @@ static int wpa_cli_cmd_ping(struct wpa_ctrl *ctrl, int argc, char *argv[])
 }
 
 
+static int wpa_cli_cmd_relog(struct wpa_ctrl *ctrl, int argc, char *argv[])
+{
+	return wpa_ctrl_command(ctrl, "RELOG");
+}
+
+
 static int wpa_cli_cmd_note(struct wpa_ctrl *ctrl, int argc, char *argv[])
 {
 	char cmd[256];
@@ -2164,6 +2170,9 @@ static struct wpa_cli_cmd wpa_cli_commands[] = {
 	{ "ping", wpa_cli_cmd_ping,
 	  cli_cmd_flag_none,
 	  "= pings wpa_supplicant" },
+	{ "relog", wpa_cli_cmd_relog,
+	  cli_cmd_flag_none,
+	  "= re-open log-file (allow rolling logs)" },
 	{ "note", wpa_cli_cmd_note,
 	  cli_cmd_flag_none,
 	  "<text> = add a note to wpa_supplicant debug log" },