commit e67651c89d0cbb759219412d49cbc5680c17df06
author San Mehat <san@google.com> Tue May 12 15:50:49 2009 -0700
committer San Mehat <san@google.com> Tue May 12 15:50:49 2009 -0700
tree e60d74806196eb4abcb7f236f05235ae72cfa4da
parent dbdb0db516fa4935ff7b5c05914932099237d808

nexus: Cleanup the scanner and plug it all in so it works

Signed-off-by: San Mehat <san@google.com>

nexus/WifiScanner.cpp

diff --git a/nexus/WifiScanner.cpp b/nexus/WifiScanner.cpp
index 590d895..1bc9722 100644
--- a/nexus/WifiScanner.cpp
+++ b/nexus/WifiScanner.cpp
@@ -1,3 +1,8 @@
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/types.h>
 #include <errno.h>
 #include <pthread.h>
 
@@ -13,28 +18,16 @@
     mSuppl = suppl;
     mPeriod = period;
     mActive = false;
-    mWorkerRunning = false;
-    mAbortRequest = false;
-    pthread_mutex_init(&mAbortRequestLock, NULL);
-    pthread_mutex_init(&mWorkerLock, NULL);
 }
 
-int WifiScanner::startPeriodicScan(bool active) {
+int WifiScanner::start(bool active) {
     mActive = active;
 
-    pthread_mutex_lock(&mWorkerLock);
-    if (mWorkerRunning) {
-        errno = EBUSY;
-        return -1;
-    }
-
-    pthread_attr_t attr;
-    pthread_attr_init(&attr);
-    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
-
-    if (pthread_create(&mWorker, &attr, WifiScanner::threadStart, this))
+    if(pipe(mCtrlPipe))
         return -1;
 
+    if (pthread_create(&mThread, NULL, WifiScanner::threadStart, this))
+        return -1;
     return 0;
 }
 
@@ -45,52 +38,49 @@
     return NULL;
 }
 
-void WifiScanner::threadCleanup(void *obj) {
-    WifiScanner *me = reinterpret_cast<WifiScanner *>(obj);
+int WifiScanner::stop() {
+    char c = 0;
 
-    me->mWorkerRunning = false;
-    pthread_mutex_unlock(&me->mWorkerLock);
-
-    if (me->mAbortRequest) {
-        me->mAbortRequest = false;
-        pthread_mutex_unlock(&me->mAbortRequestLock);
+    if (write(mCtrlPipe[1], &c, 1) != 1) {
+        LOGE("Error writing to control pipe (%s)", strerror(errno));
+        return -1;
     }
-}
 
-int WifiScanner::stopPeriodicScan() {
-    pthread_mutex_lock(&mAbortRequestLock);
-    pthread_mutex_lock(&mWorkerLock);
-    if (mWorkerRunning)
-        mAbortRequest = true;
-    pthread_mutex_unlock(&mWorkerLock);
-    pthread_mutex_unlock(&mAbortRequestLock);
+    void *ret;
+    if (pthread_join(mThread, &ret)) {
+        LOGE("Error joining to scanner thread (%s)", strerror(errno));
+        return -1;
+    }
 
+    close(mCtrlPipe[0]);
+    close(mCtrlPipe[1]);
     return 0;
 }
 
 void WifiScanner::run() {
-    LOGD("Thread started");
-
-    mWorkerRunning = true;
-    pthread_cleanup_push(WifiScanner::threadCleanup, this);
-    pthread_mutex_unlock(&mWorkerLock);
+    LOGD("Starting wifi scanner (active = %d)", mActive);
 
     while(1) {
-        LOGD("Triggering periodic scan");
+        fd_set read_fds;
+        struct timeval to;
+        int rc = 0;
+
+        to.tv_sec = 0;
+        to.tv_sec = mPeriod;
+
+        FD_ZERO(&read_fds);
+        FD_SET(mCtrlPipe[0], &read_fds);
+
         if (mSuppl->triggerScan(mActive)) {
             LOGW("Error triggering scan (%s)", strerror(errno));
         }
 
-        sleep(mPeriod);
-        pthread_mutex_lock(&mAbortRequestLock);
-        if (mAbortRequest) {
-            LOGD("Abort request!");
-            goto out;
-        }
-        pthread_mutex_unlock(&mAbortRequestLock);
-    }
-
-out:
-    pthread_cleanup_pop(1);
-    pthread_mutex_unlock(&mWorkerLock);
+        if ((rc = select(mCtrlPipe[0] + 1, &read_fds, NULL, NULL, &to)) < 0) {
+            LOGE("select failed (%s) - sleeping for one scanner period", strerror(errno));
+            sleep(mPeriod);
+            continue;
+        } else if (!rc) {
+        } else if (FD_ISSET(mCtrlPipe[0], &read_fds))
+            break;
+    } // while
 }