Find a list of devices instead of a single one

Several devices may match the requested serial, but above all, this
paves the way to list all devices (when no serial is provided).

PR #2974 <https://github.com/Genymobile/scrcpy/pull/2974>

app/src/scrcpy.c

@@ -432,21 +432,32 @@ scrcpy(struct scrcpy_options *options) {
             }
 
             assert(serial);
-            struct sc_usb_device usb_device;
-            ok = sc_usb_find_device(&s->usb, serial, &usb_device);
-            if (!ok) {
+            struct sc_usb_device usb_devices[16];
+            ssize_t count = sc_usb_find_devices(&s->usb, serial, usb_devices,
+                                                ARRAY_LEN(usb_devices));
+            if (count <= 0) {
                 LOGE("Could not find USB device %s", serial);
                 sc_usb_destroy(&s->usb);
                 sc_acksync_destroy(&s->acksync);
                 goto aoa_hid_end;
             }
 
+            if (count > 1) {
+                LOGE("Multiple (%d) devices with serial %s", (int) count, serial);
+                sc_usb_device_destroy_all(usb_devices, count);
+                sc_usb_destroy(&s->usb);
+                sc_acksync_destroy(&s->acksync);
+                goto aoa_hid_end;
+            }
+
+            struct sc_usb_device *usb_device = &usb_devices[0];
+
             LOGI("USB device: %s (%04" PRIx16 ":%04" PRIx16 ") %s %s",
-                 usb_device.serial, usb_device.vid, usb_device.pid,
-                 usb_device.manufacturer, usb_device.product);
+                 usb_device->serial, usb_device->vid, usb_device->pid,
+                 usb_device->manufacturer, usb_device->product);
 
-            ok = sc_usb_connect(&s->usb, usb_device.device);
-            sc_usb_device_destroy(&usb_device);
+            ok = sc_usb_connect(&s->usb, usb_device->device);
+            sc_usb_device_destroy(usb_device);
             if (!ok) {
                 LOGE("Failed to connect to USB device %s", serial);
                 sc_usb_destroy(&s->usb);

app/src/usb/usb.c

@@ -80,29 +80,36 @@ sc_usb_device_destroy(struct sc_usb_device *usb_device) {
     free(usb_device->product);
 }
 
-bool
-sc_usb_find_device(struct sc_usb *usb, const char *serial,
-                   struct sc_usb_device *out) {
+void
+sc_usb_device_destroy_all(struct sc_usb_device *usb_devices, size_t count) {
+    for (size_t i = 0; i < count; ++i) {
+        sc_usb_device_destroy(&usb_devices[i]);
+    }
+}
+
+ssize_t
+sc_usb_find_devices(struct sc_usb *usb, const char *serial,
+                    struct sc_usb_device *devices, size_t len) {
     assert(serial);
 
     libusb_device **list;
     ssize_t count = libusb_get_device_list(usb->context, &list);
     if (count < 0) {
         log_libusb_error((enum libusb_error) count);
-        return false;
+        return -1;
     }
 
-    for (size_t i = 0; i < (size_t) count; ++i) {
+    size_t idx = 0;
+    for (size_t i = 0; i < (size_t) count && idx < len; ++i) {
         libusb_device *device = list[i];
 
-        if (accept_device(device, serial, out)) {
-            libusb_free_device_list(list, 1);
-            return true;
+        if (accept_device(device, serial, &devices[idx])) {
+            ++idx;
         }
     }
 
     libusb_free_device_list(list, 1);
-    return false;
+    return idx;
 }
 
 static libusb_device_handle *

app/src/usb/usb.h

@@ -23,15 +23,18 @@ struct sc_usb_device {
 void
 sc_usb_device_destroy(struct sc_usb_device *usb_device);
 
+void
+sc_usb_device_destroy_all(struct sc_usb_device *usb_devices, size_t count);
+
 bool
 sc_usb_init(struct sc_usb *usb);
 
 void
 sc_usb_destroy(struct sc_usb *usb);
 
-bool
-sc_usb_find_device(struct sc_usb *usb, const char *serial,
-                   struct sc_usb_device *out);
+ssize_t
+sc_usb_find_devices(struct sc_usb *usb, const char *serial,
+                    struct sc_usb_device *devices, size_t len);
 
 bool
 sc_usb_connect(struct sc_usb *usb, libusb_device *device);