Allow fuzzy_fastboot number to run for a specific device serial number

Test: ./fuzzy_fastboot --serial=826X003L --gtest_filter=*Logical*
Bug: 117181762
Change-Id: I9dec510aa604b7994f25ce26edb87d7f6ec3e875
diff --git a/fastboot/fuzzy_fastboot/fixtures.cpp b/fastboot/fuzzy_fastboot/fixtures.cpp
index c23da01..bc13a8c 100644
--- a/fastboot/fuzzy_fastboot/fixtures.cpp
+++ b/fastboot/fuzzy_fastboot/fixtures.cpp
@@ -59,7 +59,7 @@
 
 namespace fastboot {
 
-int FastBootTest::MatchFastboot(usb_ifc_info* info, const char* local_serial) {
+int FastBootTest::MatchFastboot(usb_ifc_info* info, const std::string& local_serial) {
     if (info->ifc_class != 0xff || info->ifc_subclass != 0x42 || info->ifc_protocol != 0x03) {
         return -1;
     }
@@ -68,8 +68,8 @@
 
     // require matching serial number or device path if requested
     // at the command line with the -s option.
-    if (local_serial && (strcmp(local_serial, info->serial_number) != 0 &&
-                         strcmp(local_serial, info->device_path) != 0))
+    if (!local_serial.empty() && local_serial != info->serial_number &&
+        local_serial != info->device_path)
         return -1;
     return 0;
 }
@@ -113,7 +113,9 @@
         ASSERT_TRUE(UsbStillAvailible());  // The device disconnected
     }
 
-    const auto matcher = [](usb_ifc_info* info) -> int { return MatchFastboot(info, nullptr); };
+    const auto matcher = [](usb_ifc_info* info) -> int {
+        return MatchFastboot(info, device_serial);
+    };
     for (int i = 0; i < MAX_USB_TRIES && !transport; i++) {
         std::unique_ptr<UsbTransport> usb(usb_open(matcher, USB_TIMEOUT));
         if (usb)
@@ -172,7 +174,9 @@
         ;
     printf("WAITING FOR DEVICE\n");
     // Need to wait for device
-    const auto matcher = [](usb_ifc_info* info) -> int { return MatchFastboot(info, nullptr); };
+    const auto matcher = [](usb_ifc_info* info) -> int {
+        return MatchFastboot(info, device_serial);
+    };
     while (!transport) {
         std::unique_ptr<UsbTransport> usb(usb_open(matcher, USB_TIMEOUT));
         if (usb) {
@@ -238,6 +242,7 @@
 std::string FastBootTest::cb_scratch = "";
 std::string FastBootTest::initial_slot = "";
 int FastBootTest::serial_port = 0;
+std::string FastBootTest::device_serial = "";
 
 template <bool UNLOCKED>
 void ModeTest<UNLOCKED>::SetUp() {
diff --git a/fastboot/fuzzy_fastboot/fixtures.h b/fastboot/fuzzy_fastboot/fixtures.h
index 7c8d54d..c71c897 100644
--- a/fastboot/fuzzy_fastboot/fixtures.h
+++ b/fastboot/fuzzy_fastboot/fixtures.h
@@ -43,9 +43,10 @@
 class FastBootTest : public testing::Test {
   public:
     static int serial_port;
+    static std::string device_serial;
     static constexpr int MAX_USB_TRIES = 10;
 
-    static int MatchFastboot(usb_ifc_info* info, const char* local_serial = nullptr);
+    static int MatchFastboot(usb_ifc_info* info, const std::string& local_serial = "");
     bool UsbStillAvailible();
     bool UserSpaceFastboot();
     void ReconnectFastbootDevice();
diff --git a/fastboot/fuzzy_fastboot/main.cpp b/fastboot/fuzzy_fastboot/main.cpp
index 7ffc7d5..82d5cc9 100644
--- a/fastboot/fuzzy_fastboot/main.cpp
+++ b/fastboot/fuzzy_fastboot/main.cpp
@@ -162,7 +162,7 @@
 // Test that USB even works
 TEST(USBFunctionality, USBConnect) {
     const auto matcher = [](usb_ifc_info* info) -> int {
-        return FastBootTest::MatchFastboot(info, nullptr);
+        return FastBootTest::MatchFastboot(info, fastboot::FastBootTest::device_serial);
     };
     Transport* transport = nullptr;
     for (int i = 0; i < FastBootTest::MAX_USB_TRIES && !transport; i++) {
@@ -1728,10 +1728,14 @@
         fastboot::GenerateXmlTests(fastboot::config);
     }
 
+    if (args.find("serial") != args.end()) {
+        fastboot::FastBootTest::device_serial = args.at("serial");
+    }
+
     setbuf(stdout, NULL);  // no buffering
     printf("<Waiting for Device>\n");
     const auto matcher = [](usb_ifc_info* info) -> int {
-        return fastboot::FastBootTest::MatchFastboot(info, nullptr);
+        return fastboot::FastBootTest::MatchFastboot(info, fastboot::FastBootTest::device_serial);
     };
     Transport* transport = nullptr;
     while (!transport) {