nexus: Initial checkin of Nexus - android native network management daemon.

    Initial skelaton

Signed-off-by: San Mehat <san@google.com>
diff --git a/nexus/Controller.cpp b/nexus/Controller.cpp
new file mode 100644
index 0000000..cc1a187
--- /dev/null
+++ b/nexus/Controller.cpp
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <malloc.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#define LOG_TAG "Controller"
+
+#include <cutils/log.h>
+
+#include "Controller.h"
+
+extern "C" int init_module(void *, unsigned int, const char *);
+extern "C" int delete_module(const char *, unsigned int);
+
+Controller::Controller(const char *name) {
+    mName = name;
+}
+
+int Controller::start() {
+    return 0;
+}
+
+int Controller::stop() {
+    return 0;
+}
+
+int Controller::loadKernelModule(char *modpath, const char *args) {
+    void *module;
+    unsigned int size;
+
+    LOGD("loadKernelModule(%s, %s)", modpath, args);
+
+    module = loadFile(modpath, &size);
+    if (!module) {
+        errno = -EIO;
+        return -1;
+    }
+
+    int rc = init_module(module, size, args);
+    free (module);
+    return rc;
+}
+
+int Controller::unloadKernelModule(const char *modtag) {
+    int rc = -1;
+    int retries = 10;
+
+    LOGD("unloadKernelModule(%s)", modtag);
+    while (retries--) {
+        rc = delete_module(modtag, O_NONBLOCK | O_EXCL);
+        if (rc < 0 && errno == EAGAIN)
+            usleep(1000*500);
+        else
+            break;
+    }
+
+    if (rc != 0) {
+        LOGW("Unable to unload kernel driver '%s' (%s)", modtag, 
+             strerror(errno));
+    }
+    return rc;
+}
+
+bool Controller::isKernelModuleLoaded(const char *modtag) {
+    FILE *fp = fopen("/proc/modules", "r");
+
+    if (!fp) {
+        LOGE("Unable to open /proc/modules (%s)", strerror(errno));
+        return false;
+    }
+
+    char line[255];
+    while(fgets(line, sizeof(line), fp)) {
+        char *endTag = strchr(line, ' ');
+
+        if (!endTag) {
+            LOGW("Unable to find tag for line '%s'", line);
+            continue;
+        }
+        if (!strncmp(line, modtag, (endTag - line))) {
+            fclose(fp);
+            return true;
+        }
+    }
+
+    fclose(fp);
+    return false;
+}
+
+
+void *Controller::loadFile(char *filename, unsigned int *_size)
+{
+	int ret, fd;
+	struct stat sb;
+	ssize_t size;
+	void *buffer = NULL;
+
+	/* open the file */
+	fd = open(filename, O_RDONLY);
+	if (fd < 0)
+		return NULL;
+
+	/* find out how big it is */
+	if (fstat(fd, &sb) < 0)
+		goto bail;
+	size = sb.st_size;
+
+	/* allocate memory for it to be read into */
+	buffer = malloc(size);
+	if (!buffer)
+		goto bail;
+
+	/* slurp it into our buffer */
+	ret = read(fd, buffer, size);
+	if (ret != size)
+		goto bail;
+
+	/* let the caller know how big it is */
+	*_size = size;
+
+bail:
+	close(fd);
+	return buffer;
+}