From cb24c37858e2628c9dba371653779ad2aa771899 Mon Sep 17 00:00:00 2001
From: Jo-Philipp Wich <jow@openwrt.org>
Date: Sun, 9 Jun 2013 14:39:09 +0000
Subject: [PATCH] libiwinfo: ignore log messages from wpa_supplicant while
 scanning

wpa_supplicant may send log and event messages intermixed with the
expected scan results.  This makes "iwinfo wlan0 scan" and LuCI
"site survey" display nothing when many AP's are around.

Eliminate the CTRL-EVENT-BSS-ADDED events, interspersed log messages,
lines with unexpected format.  Increase timeout to handle the max
number of channels (2.4, 3.6, 4.9, 5 GHz).  Insure receive buffer is
null-terminated.

Signed-off-by: Jean-Pierre Tosoni <jp.tosoni@acksys.fr>

SVN-Revision: 36888
---
 .../network/utils/iwinfo/src/iwinfo_nl80211.c | 63 ++++++++++++++-----
 1 file changed, 47 insertions(+), 16 deletions(-)

diff --git a/package/network/utils/iwinfo/src/iwinfo_nl80211.c b/package/network/utils/iwinfo/src/iwinfo_nl80211.c
index 700410939d..051d34dd1c 100644
--- a/package/network/utils/iwinfo/src/iwinfo_nl80211.c
+++ b/package/network/utils/iwinfo/src/iwinfo_nl80211.c
@@ -540,16 +540,21 @@ static char * nl80211_wpactl_info(const char *ifname, const char *cmd,
 	{
 		send(sock, "ATTACH", 6, 0);
 
-		if (nl80211_wpactl_recv(sock, buffer, sizeof(buffer)) <= 0)
+		if (nl80211_wpactl_recv(sock, buffer, sizeof(buffer)-1) <= 0)
 			goto out;
 	}
 
 
 	send(sock, cmd, strlen(cmd), 0);
 
-	while( numtry++ < 5 )
+	/* we might have to scan up to 72 channels / 256ms per channel */
+	/* this makes up to 18.5s hence 10 tries */
+	while( numtry++ < 10 )
 	{
-		if (nl80211_wpactl_recv(sock, buffer, sizeof(buffer)) <= 0)
+		char *bracket;
+
+		/* make sure there is a terminating nul byte */
+		if (nl80211_wpactl_recv(sock, buffer, sizeof(buffer)-1) <= 0)
 		{
 			if (event)
 				continue;
@@ -559,6 +564,13 @@ static char * nl80211_wpactl_info(const char *ifname, const char *cmd,
 
 		if ((!event && buffer[0] != '<') || (event && strstr(buffer, event)))
 			break;
+
+		/* there may be more than max(numtry) BSS-ADDED events */
+		/* ignore them similar to wpa_cli */
+		if (buffer[0] == '<' &&
+				(bracket=strchr(buffer,'>')) != NULL &&
+				strncmp(bracket+1,"CTRL-EVENT-BSS-ADDED",20) == 0)
+			numtry--;
 	}
 
 	rv = buffer;
@@ -1751,8 +1763,10 @@ static int nl80211_get_scanlist_cb(struct nl_msg *msg, void *arg)
 
 	if (caps & (1<<1))
 		sl->e->mode = IWINFO_OPMODE_ADHOC;
-	else
+	else if (caps & (1<<0))
 		sl->e->mode = IWINFO_OPMODE_MASTER;
+	else
+		sl->e->mode = IWINFO_OPMODE_MESHPOINT;
 
 	if (caps & (1<<4))
 		sl->e->crypto.enabled = 1;
@@ -1852,14 +1866,26 @@ int nl80211_get_scanlist(const char *ifname, char *buf, int *len)
 		{
 			nl80211_get_quality_max(ifname, &qmax);
 
-			/* skip header line */
-			while (*res++ != '\n');
+			count = -1;
 
-			count = 0;
-
-			while (sscanf(res, "%17s %d %d %255s%*[ \t]%127[^\n]\n",
-			              bssid, &freq, &rssi, cipher, ssid) > 0)
-			{
+			do {
+				if (res[0] == '<')
+				{
+					/* skip log lines */
+					goto nextline;
+				}
+				if (count < 0)
+				{
+					/* skip header line */
+					count++;
+					goto nextline;
+				}
+				if (sscanf(res, "%17s %d %d %255s%*[ \t]%127[^\n]\n",
+					      bssid, &freq, &rssi, cipher, ssid) < 5)
+				{
+					/* skip malformed lines */
+					goto nextline;
+				}
 				/* BSSID */
 				e->mac[0] = strtol(&bssid[0],  NULL, 16);
 				e->mac[1] = strtol(&bssid[3],  NULL, 16);
@@ -1872,7 +1898,10 @@ int nl80211_get_scanlist(const char *ifname, char *buf, int *len)
 				memcpy(e->ssid, ssid, min(strlen(ssid), sizeof(e->ssid) - 1));
 
 				/* Mode (assume master) */
-				e->mode = IWINFO_OPMODE_MASTER;
+				if (strstr(cipher,"[MESH]"))
+					e->mode = IWINFO_OPMODE_MESHPOINT;
+				else
+					e->mode = IWINFO_OPMODE_MASTER;
 
 				/* Channel */
 				e->channel = nl80211_freq2channel(freq);
@@ -1904,16 +1933,18 @@ int nl80211_get_scanlist(const char *ifname, char *buf, int *len)
 				/* Crypto */
 				nl80211_get_scancrypto(cipher, &e->crypto);
 
-				/* advance to next line */
-				while (*res && *res++ != '\n');
-
 				count++;
 				e++;
 
 				memset(ssid, 0, sizeof(ssid));
 				memset(bssid, 0, sizeof(bssid));
 				memset(cipher, 0, sizeof(cipher));
-			}
+
+			nextline:
+				/* advance to next line */
+				while( *res && *res++ != '\n' );
+ 			}
+			while( *res );
 
 			*len = count * sizeof(struct iwinfo_scanlist_entry);
 			return 0;