Share the new adb USB diagnostic code with fastboot.
Bug: http://b/26134129
Change-Id: Ieaf0651c7b3f8a028760982091ec63a21a5484ba
diff --git a/adb/diagnose_usb.cpp b/adb/diagnose_usb.cpp
new file mode 100644
index 0000000..0f067b0
--- /dev/null
+++ b/adb/diagnose_usb.cpp
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2015 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 "diagnose_usb.h"
+
+#include <errno.h>
+#include <unistd.h>
+
+#include <string>
+
+#include <android-base/stringprintf.h>
+
+#if defined(__linux__)
+#include <grp.h>
+#endif
+
+static const char kPermissionsHelpUrl[] = "http://developer.android.com/tools/device.html";
+
+// Returns a message describing any potential problems we find with udev, or nullptr if we can't
+// find plugdev information (i.e. udev is not installed).
+static const char* GetUdevProblem() {
+#if defined(__linux__)
+ errno = 0;
+ group* plugdev_group = getgrnam("plugdev");
+
+ if (plugdev_group == nullptr) {
+ if (errno != 0) {
+ perror("failed to read plugdev group info");
+ }
+ // We can't give any generally useful advice here, just let the caller print the help URL.
+ return nullptr;
+ }
+
+ // getgroups(2) indicates that the group_member() may not check the egid so we check it
+ // additionally just to be sure.
+ if (group_member(plugdev_group->gr_gid) || getegid() == plugdev_group->gr_gid) {
+ // The user is in plugdev so the problem is likely with the udev rules.
+ return "verify udev rules";
+ }
+ return "udev requires plugdev group membership";
+#else
+ return nullptr;
+#endif
+}
+
+// Short help text must be a single line, and will look something like:
+// no permissions (reason); see <URL>
+std::string UsbNoPermissionsShortHelpText() {
+ std::string help_text = "no permissions";
+
+ const char* problem = GetUdevProblem();
+ if (problem != nullptr) {
+ help_text += android::base::StringPrintf(" (%s)", problem);
+ }
+
+ return android::base::StringPrintf("%s; see [%s]", help_text.c_str(), kPermissionsHelpUrl);
+}
+
+// Long help text can span multiple lines and should provide more detailed information.
+std::string UsbNoPermissionsLongHelpText() {
+ std::string header = "insufficient permissions for device";
+
+ const char* problem = GetUdevProblem();
+ if (problem != nullptr) {
+ header += android::base::StringPrintf(": %s", problem);
+ }
+
+ return android::base::StringPrintf("%s.\nSee [%s] for more information.",
+ header.c_str(), kPermissionsHelpUrl);
+}