Add interface name to wpa_msg() output

This makes log files much more readable if multiple interfaces
are being controlled by the same process. The interface name is
added to stdout/file/syslog entries, but not to the messages
sent to control interface monitors to avoid issues with parsing
in external programs.

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

src/utils/wpa_debug.c

@@ -348,12 +348,21 @@ void wpa_msg_register_cb(wpa_msg_cb_func func)
 }
 
 
+static wpa_msg_get_ifname_func wpa_msg_ifname_cb = NULL;
+
+void wpa_msg_register_ifname_cb(wpa_msg_get_ifname_func func)
+{
+	wpa_msg_ifname_cb = func;
+}
+
+
 void wpa_msg(void *ctx, int level, const char *fmt, ...)
 {
 	va_list ap;
 	char *buf;
 	const int buflen = 2048;
 	int len;
+	char prefix[130];
 
 	buf = os_malloc(buflen);
 	if (buf == NULL) {
@@ -362,9 +371,19 @@ void wpa_msg(void *ctx, int level, const char *fmt, ...)
 		return;
 	}
 	va_start(ap, fmt);
+	prefix[0] = '\0';
+	if (wpa_msg_ifname_cb) {
+		const char *ifname = wpa_msg_ifname_cb(ctx);
+		if (ifname) {
+			int res = os_snprintf(prefix, sizeof(prefix), "%s: ",
+					      ifname);
+			if (res < 0 || res >= (int) sizeof(prefix))
+				prefix[0] = '\0';
+		}
+	}
 	len = vsnprintf(buf, buflen, fmt, ap);
 	va_end(ap);
-	wpa_printf(level, "%s", buf);
+	wpa_printf(level, "%s%s", prefix, buf);
 	if (wpa_msg_cb)
 		wpa_msg_cb(ctx, level, buf, len);
 	os_free(buf);

src/utils/wpa_debug.h

@@ -188,8 +188,11 @@ typedef void (*wpa_msg_cb_func)(void *ctx, int level, const char *txt,
  * @func: Callback function (%NULL to unregister)
  */
 void wpa_msg_register_cb(wpa_msg_cb_func func);
-#endif /* CONFIG_NO_WPA_MSG */
 
+typedef const char * (*wpa_msg_get_ifname_func)(void *ctx);
+void wpa_msg_register_ifname_cb(wpa_msg_get_ifname_func func);
+
+#endif /* CONFIG_NO_WPA_MSG */
 
 #ifdef CONFIG_NO_HOSTAPD_LOGGER
 #define hostapd_logger(args...) do { } while (0)

wpa_supplicant/wpa_supplicant.c

@@ -2333,6 +2333,15 @@ struct wpa_supplicant * wpa_supplicant_get_iface(struct wpa_global *global,
 }
 
 
+static const char * wpa_supplicant_msg_ifname_cb(void *ctx)
+{
+	struct wpa_supplicant *wpa_s = ctx;
+	if (wpa_s == NULL)
+		return NULL;
+	return wpa_s->ifname;
+}
+
+
 /**
  * wpa_supplicant_init - Initialize %wpa_supplicant
  * @params: Parameters for %wpa_supplicant
@@ -2350,6 +2359,8 @@ struct wpa_global * wpa_supplicant_init(struct wpa_params *params)
 	if (params == NULL)
 		return NULL;
 
+	wpa_msg_register_ifname_cb(wpa_supplicant_msg_ifname_cb);
+
 	wpa_debug_open_file(params->wpa_debug_file_path);
 	if (params->wpa_debug_syslog)
 		wpa_debug_open_syslog();