Build on Windows with libusb support

Add LIBUSB_CALL so that the callback has the correct signature on
Windows (including __attribute__((stdcall))).

README.md

@@ -422,7 +422,7 @@ scrcpy -b2M -m800  # short version
 
 #### Multi-devices
 
-If several devices are listed in `adb devices`, you must specify the _serial_:
+If several devices are listed in `adb devices`, you can specify the _serial_:
 
 ```bash
 scrcpy --serial 0123456789abcdef
@@ -436,6 +436,19 @@ scrcpy --serial 192.168.0.1:5555
 scrcpy -s 192.168.0.1:5555  # short version
 ```
 
+If only one device is connected via either USB or TCP/IP, it is possible to
+select it automatically:
+
+```bash
+# Select the only device connected via USB
+scrcpy --select-usb
+scrcpy -U  # short version
+
+# Select the only device connected via TCP/IP
+scrcpy --select-tcpip
+scrcpy -T  # short version
+```
+
 You can start several instances of _scrcpy_ for several devices.
 
 #### Autostart on device connection

app/meson.build

@@ -1,6 +1,7 @@
 src = [
     'src/main.c',
     'src/adb/adb.c',
+    'src/adb/adb_device.c',
     'src/adb/adb_parser.c',
     'src/adb/adb_tunnel.c',
     'src/cli.c',
@@ -72,7 +73,7 @@ if v4l2_support
     src += [ 'src/v4l2_sink.c' ]
 endif
 
-usb_support = host_machine.system() == 'linux'
+usb_support = host_machine.system() == 'linux' or host_machine.system() == 'windows'
 if usb_support
     src += [
         'src/usb/aoa_hid.c',
@@ -139,9 +140,22 @@ else
         include_directories: include_directories(ffmpeg_include_dir)
     )
 
+    prebuilt_libusb = meson.get_cross_property('prebuilt_libusb')
+    prebuilt_libusb_root = meson.get_cross_property('prebuilt_libusb_root')
+    libusb_bin_dir = meson.current_source_dir() + '/../prebuilt-deps/data/' + prebuilt_libusb + '/dll'
+    libusb_include_dir = '../prebuilt-deps/data/' + prebuilt_libusb_root + '/include'
+
+    libusb = declare_dependency(
+        dependencies: [
+            cc.find_library('libusb-1.0', dirs: libusb_bin_dir),
+        ],
+        include_directories: include_directories(libusb_include_dir)
+    )
+
     dependencies = [
         ffmpeg,
         sdl2,
+        libusb,
         cc.find_library('mingw32')
     ]
 
@@ -221,6 +235,7 @@ if get_option('buildtype') == 'debug'
     tests = [
         ['test_adb_parser', [
             'tests/test_adb_parser.c',
+            'src/adb/adb_device.c',
             'src/adb/adb_parser.c',
             'src/util/str.c',
             'src/util/strbuf.c',

app/scrcpy.1

@@ -273,6 +273,14 @@ Set the TCP port of the adb tunnel to reach the scrcpy server. This option autom
 
 Default is 0 (not forced): the local port used for establishing the tunnel will be used.
 
+.TP
+.B \-T, \-\-select\-tcpip
+Use TCP/IP device (if there is exactly one).
+
+.TP
+.B \-U, \-\-select\-usb
+Use USB device (if there is exactly one).
+
 .TP
 .BI "\-\-v4l2-sink " /dev/videoN
 Output to v4l2loopback device.

app/src/adb/adb.c

@@ -194,6 +194,14 @@ sc_adb_execute(const char *const argv[], unsigned flags) {
     return sc_adb_execute_p(argv, flags, NULL);
 }
 
+bool
+sc_adb_start_server(struct sc_intr *intr, unsigned flags) {
+    const char *const argv[] = SC_ADB_COMMAND("start-server");
+
+    sc_pid pid = sc_adb_execute(argv, flags);
+    return process_check_success_intr(intr, pid, "adb start-server", flags);
+}
+
 bool
 sc_adb_forward(struct sc_intr *intr, const char *serial, uint16_t local_port,
                const char *device_socket_name, unsigned flags) {
@@ -374,6 +382,234 @@ sc_adb_disconnect(struct sc_intr *intr, const char *ip_port, unsigned flags) {
     return process_check_success_intr(intr, pid, "adb disconnect", flags);
 }
 
+static ssize_t
+sc_adb_list_devices(struct sc_intr *intr, unsigned flags,
+                    struct sc_adb_device *devices, size_t len) {
+    const char *const argv[] = SC_ADB_COMMAND("devices", "-l");
+
+    sc_pipe pout;
+    sc_pid pid = sc_adb_execute_p(argv, flags, &pout);
+    if (pid == SC_PROCESS_NONE) {
+        LOGE("Could not execute \"adb devices -l\"");
+        return -1;
+    }
+
+    char buf[4096];
+    ssize_t r = sc_pipe_read_all_intr(intr, pid, pout, buf, sizeof(buf) - 1);
+    sc_pipe_close(pout);
+
+    bool ok = process_check_success_intr(intr, pid, "adb devices -l", flags);
+    if (!ok) {
+        return -1;
+    }
+
+    if (r == -1) {
+        return -1;
+    }
+
+    assert((size_t) r < sizeof(buf));
+    if (r == sizeof(buf) - 1)  {
+        // The implementation assumes that the output of "adb devices -l" fits
+        // in the buffer in a single pass
+        LOGW("Result of \"adb devices -l\" does not fit in 4Kb. "
+             "Please report an issue.\n");
+        return -1;
+    }
+
+    // It is parsed as a NUL-terminated string
+    buf[r] = '\0';
+
+    // List all devices to the output list directly
+    return sc_adb_parse_devices(buf, devices, len);
+}
+
+static bool
+sc_adb_accept_device(const struct sc_adb_device *device,
+                     const struct sc_adb_device_selector *selector) {
+    switch (selector->type) {
+        case SC_ADB_DEVICE_SELECT_ALL:
+            return true;
+        case SC_ADB_DEVICE_SELECT_SERIAL:
+            assert(selector->serial);
+            char *device_serial_colon = strchr(device->serial, ':');
+            if (device_serial_colon) {
+                // The device serial is an IP:port...
+                char *serial_colon = strchr(selector->serial, ':');
+                if (!serial_colon) {
+                    // But the requested serial has no ':', so only consider
+                    // the IP part of the device serial. This allows to use
+                    // "192.168.1.1" to match any "192.168.1.1:port".
+                    size_t serial_len = strlen(selector->serial);
+                    size_t device_ip_len = device_serial_colon - device->serial;
+                    if (serial_len != device_ip_len) {
+                        // They are not equal, they don't even have the same
+                        // length
+                        return false;
+                    }
+                    return !strncmp(selector->serial, device->serial,
+                                    device_ip_len);
+                }
+            }
+            return !strcmp(selector->serial, device->serial);
+        case SC_ADB_DEVICE_SELECT_USB:
+            return !sc_adb_is_serial_tcpip(device->serial);
+        case SC_ADB_DEVICE_SELECT_TCPIP:
+            return sc_adb_is_serial_tcpip(device->serial);
+        default:
+            assert(!"Missing SC_ADB_DEVICE_SELECT_* handling");
+            break;
+    }
+
+    return false;
+}
+
+static size_t
+sc_adb_devices_select(struct sc_adb_device *devices, size_t len,
+                      const struct sc_adb_device_selector *selector,
+                      size_t *idx_out) {
+    size_t count = 0;
+    for (size_t i = 0; i < len; ++i) {
+        struct sc_adb_device *device = &devices[i];
+        device->selected = sc_adb_accept_device(device, selector);
+        if (device->selected) {
+            if (idx_out && !count) {
+                *idx_out = i;
+            }
+            ++count;
+        }
+    }
+
+    return count;
+}
+
+static void
+sc_adb_devices_log(enum sc_log_level level, struct sc_adb_device *devices,
+                   size_t count) {
+    for (size_t i = 0; i < count; ++i) {
+        struct sc_adb_device *d = &devices[i];
+        const char *selection = d->selected ? "-->" : "   ";
+        const char *type = sc_adb_is_serial_tcpip(d->serial) ? "(tcpip)"
+                                                             : "  (usb)";
+        LOG(level, "    %s %s  %-20s  %16s  %s",
+             selection, type, d->serial, d->state, d->model ? d->model : "");
+    }
+}
+
+static bool
+sc_adb_device_check_state(struct sc_adb_device *device,
+                          struct sc_adb_device *devices, size_t count) {
+    const char *state = device->state;
+
+    if (!strcmp("device", state)) {
+        return true;
+    }
+
+    if (!strcmp("unauthorized", state)) {
+        LOGE("Device is unauthorized:");
+        sc_adb_devices_log(SC_LOG_LEVEL_ERROR, devices, count);
+        LOGE("A popup should open on the device to request authorization.");
+        LOGE("Check the FAQ: "
+             "<https://github.com/Genymobile/scrcpy/blob/master/FAQ.md>");
+    }
+
+    return false;
+}
+
+bool
+sc_adb_select_device(struct sc_intr *intr,
+                     const struct sc_adb_device_selector *selector,
+                     unsigned flags, struct sc_adb_device *out_device) {
+    struct sc_adb_device devices[16];
+    ssize_t count =
+        sc_adb_list_devices(intr, flags, devices, ARRAY_LEN(devices));
+    if (count == -1) {
+        LOGE("Could not list ADB devices");
+        return false;
+    }
+
+    if (count == 0) {
+        LOGE("Could not find any ADB device");
+        return false;
+    }
+
+    size_t sel_idx; // index of the single matching device if sel_count == 1
+    size_t sel_count =
+        sc_adb_devices_select(devices, count, selector, &sel_idx);
+
+    if (sel_count == 0) {
+        // if count > 0 && sel_count == 0, then necessarily a selection is
+        // requested
+        assert(selector->type != SC_ADB_DEVICE_SELECT_ALL);
+
+        switch (selector->type) {
+            case SC_ADB_DEVICE_SELECT_SERIAL:
+                assert(selector->serial);
+                LOGE("Could not find ADB device %s:", selector->serial);
+                break;
+            case SC_ADB_DEVICE_SELECT_USB:
+                LOGE("Could not find any ADB device over USB:");
+                break;
+            case SC_ADB_DEVICE_SELECT_TCPIP:
+                LOGE("Could not find any ADB device over TCP/IP:");
+                break;
+            default:
+                assert(!"Unexpected selector type");
+                break;
+        }
+
+        sc_adb_devices_log(SC_LOG_LEVEL_ERROR, devices, count);
+        sc_adb_devices_destroy_all(devices, count);
+        return false;
+    }
+
+    if (sel_count > 1) {
+        switch (selector->type) {
+            case SC_ADB_DEVICE_SELECT_ALL:
+                LOGE("Multiple (%" SC_PRIsizet ") ADB devices:", sel_count);
+                break;
+            case SC_ADB_DEVICE_SELECT_SERIAL:
+                assert(selector->serial);
+                LOGE("Multiple (%" SC_PRIsizet ") ADB devices with serial %s:",
+                     sel_count, selector->serial);
+                break;
+            case SC_ADB_DEVICE_SELECT_USB:
+                LOGE("Multiple (%" SC_PRIsizet ") ADB devices over USB:",
+                     sel_count);
+                break;
+            case SC_ADB_DEVICE_SELECT_TCPIP:
+                LOGE("Multiple (%" SC_PRIsizet ") ADB devices over TCP/IP:",
+                     sel_count);
+                break;
+            default:
+                assert(!"Unexpected selector type");
+                break;
+        }
+        sc_adb_devices_log(SC_LOG_LEVEL_ERROR, devices, count);
+        if (selector->type != SC_ADB_DEVICE_SELECT_ALL) {
+            LOGE("Specify the device via -s or --serial");
+        }
+        sc_adb_devices_destroy_all(devices, count);
+        return false;
+    }
+
+    assert(sel_count == 1); // sel_idx is valid only if sel_count == 1
+    struct sc_adb_device *device = &devices[sel_idx];
+
+    bool ok = sc_adb_device_check_state(device, devices, count);
+    if (!ok) {
+        sc_adb_devices_destroy_all(devices, count);
+        return false;
+    }
+
+    LOGD("ADB device found:");
+    sc_adb_devices_log(SC_LOG_LEVEL_DEBUG, devices, count);
+
+    // Move devics into out_device (do not destroy device)
+    sc_adb_device_move(out_device, device);
+    sc_adb_devices_destroy_all(devices, count);
+    return true;
+}
+
 char *
 sc_adb_getprop(struct sc_intr *intr, const char *serial, const char *prop,
                unsigned flags) {
@@ -409,38 +645,6 @@ sc_adb_getprop(struct sc_intr *intr, const char *serial, const char *prop,
     return strdup(buf);
 }
 
-char *
-sc_adb_get_serialno(struct sc_intr *intr, unsigned flags) {
-    const char *const argv[] = SC_ADB_COMMAND("get-serialno");
-
-    sc_pipe pout;
-    sc_pid pid = sc_adb_execute_p(argv, flags, &pout);
-    if (pid == SC_PROCESS_NONE) {
-        LOGE("Could not execute \"adb get-serialno\"");
-        return NULL;
-    }
-
-    char buf[128];
-    ssize_t r = sc_pipe_read_all_intr(intr, pid, pout, buf, sizeof(buf) - 1);
-    sc_pipe_close(pout);
-
-    bool ok = process_check_success_intr(intr, pid, "adb get-serialno", flags);
-    if (!ok) {
-        return NULL;
-    }
-
-    if (r == -1) {
-        return NULL;
-    }
-
-    assert((size_t) r < sizeof(buf));
-    buf[r] = '\0';
-    size_t len = strcspn(buf, " \r\n");
-    buf[len] = '\0';
-
-    return strdup(buf);
-}
-
 char *
 sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags) {
     assert(serial);
@@ -482,3 +686,8 @@ sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags) {
 
     return sc_adb_parse_device_ip_from_output(buf);
 }
+
+bool
+sc_adb_is_serial_tcpip(const char *serial) {
+    return strchr(serial, ':');
+}

app/src/adb/adb.h

@@ -6,6 +6,7 @@
 #include <stdbool.h>
 #include <inttypes.h>
 
+#include "adb_device.h"
 #include "util/intr.h"
 
 #define SC_ADB_NO_STDOUT (1 << 0)
@@ -17,9 +18,24 @@
 const char *
 sc_adb_get_executable(void);
 
+enum sc_adb_device_selector_type {
+    SC_ADB_DEVICE_SELECT_ALL,
+    SC_ADB_DEVICE_SELECT_SERIAL,
+    SC_ADB_DEVICE_SELECT_USB,
+    SC_ADB_DEVICE_SELECT_TCPIP,
+};
+
+struct sc_adb_device_selector {
+    enum sc_adb_device_selector_type type;
+    const char *serial;
+};
+
 sc_pid
 sc_adb_execute(const char *const argv[], unsigned flags);
 
+bool
+sc_adb_start_server(struct sc_intr *intr, unsigned flags);
+
 bool
 sc_adb_forward(struct sc_intr *intr, const char *serial, uint16_t local_port,
                const char *device_socket_name, unsigned flags);
@@ -69,6 +85,16 @@ sc_adb_connect(struct sc_intr *intr, const char *ip_port, unsigned flags);
 bool
 sc_adb_disconnect(struct sc_intr *intr, const char *ip_port, unsigned flags);
 
+/**
+ * Execute `adb devices` and parse the result to select a device
+ *
+ * Return true if a single matching device is found, and write it to out_device.
+ */
+bool
+sc_adb_select_device(struct sc_intr *intr,
+                     const struct sc_adb_device_selector *selector,
+                     unsigned flags, struct sc_adb_device *out_device);
+
 /**
  * Execute `adb getprop <prop>`
  */
@@ -76,14 +102,6 @@ char *
 sc_adb_getprop(struct sc_intr *intr, const char *serial, const char *prop,
                unsigned flags);
 
-/**
- * Execute `adb get-serialno`
- *
- * Return the result, to be freed by the caller, or NULL on error.
- */
-char *
-sc_adb_get_serialno(struct sc_intr *intr, unsigned flags);
-
 /**
  * Attempt to retrieve the device IP
  *
@@ -93,4 +111,13 @@ sc_adb_get_serialno(struct sc_intr *intr, unsigned flags);
 char *
 sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags);
 
+/**
+ * Indicate if the serial represents an IP address
+ *
+ * In practice, it just returns true if and only if it contains a ':', which is
+ * sufficient to distinguish an ip:port from a real USB serial.
+ */
+bool
+sc_adb_is_serial_tcpip(const char *serial);
+
 #endif

app/src/adb/adb_device.c

@@ -0,0 +1,26 @@
+#include "adb_device.h"
+
+#include <stdlib.h>
+
+void
+sc_adb_device_destroy(struct sc_adb_device *device) {
+    free(device->serial);
+    free(device->state);
+    free(device->model);
+}
+
+void
+sc_adb_device_move(struct sc_adb_device *dst, struct sc_adb_device *src) {
+    *dst = *src;
+    src->serial = NULL;
+    src->state = NULL;
+    src->model = NULL;
+}
+
+void
+sc_adb_devices_destroy_all(struct sc_adb_device *devices, size_t count) {
+    for (size_t i = 0; i < count; ++i) {
+        sc_adb_device_destroy(&devices[i]);
+    }
+}
+

app/src/adb/adb_device.h

@@ -0,0 +1,34 @@
+#ifndef SC_ADB_DEVICE_H
+#define SC_ADB_DEVICE_H
+
+#include "common.h"
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct sc_adb_device {
+    char *serial;
+    char *state;
+    char *model;
+    bool selected;
+};
+
+void
+sc_adb_device_destroy(struct sc_adb_device *device);
+
+/**
+ * Move src to dest
+ *
+ * After this call, the content of src is undefined, except that
+ * sc_adb_device_destroy() can be called.
+ *
+ * This is useful to take a device from a list that will be destroyed, without
+ * making unnecessary copies.
+ */
+void
+sc_adb_device_move(struct sc_adb_device *dst, struct sc_adb_device *src);
+
+void
+sc_adb_devices_destroy_all(struct sc_adb_device *devices, size_t count);
+
+#endif

app/src/adb/adb_parser.c

@@ -1,11 +1,170 @@
 #include "adb_parser.h"
 
 #include <assert.h>
+#include <stdlib.h>
 #include <string.h>
 
 #include "util/log.h"
 #include "util/str.h"
 
+bool
+sc_adb_parse_device(char *line, struct sc_adb_device *device) {
+    // One device line looks like:
+    // "0123456789abcdef	device usb:2-1 product:MyProduct model:MyModel "
+    //     "device:MyDevice transport_id:1"
+
+    if (line[0] == '*') {
+        // Garbage lines printed by adb daemon while starting start with a '*'
+        return false;
+    }
+
+    if (!strncmp("adb server", line, sizeof("adb server") - 1)) {
+        // Ignore lines starting with "adb server":
+        //   adb server version (41) doesn't match this client (39); killing...
+        return false;
+    }
+
+    char *s = line; // cursor in the line
+
+    // After the serial:
+    //  - "adb devices" writes a single '\t'
+    //  - "adb devices -l" writes multiple spaces
+    // For flexibility, accept both.
+    size_t serial_len = strcspn(s, " \t");
+    if (!serial_len) {
+        // empty serial
+        return false;
+    }
+    bool eol = s[serial_len] == '\0';
+    if (eol) {
+        // serial alone is unexpected
+        return false;
+    }
+    s[serial_len] = '\0';
+    char *serial = s;
+    s += serial_len + 1;
+    // After the serial, there might be several spaces
+    s += strspn(s, " \t"); // consume all separators
+
+    size_t state_len = strcspn(s, " ");
+    if (!state_len) {
+        // empty state
+        return false;
+    }
+    eol = s[state_len] == '\0';
+    s[state_len] = '\0';
+    char *state = s;
+
+    char *model = NULL;
+    if (!eol) {
+        s += state_len + 1;
+
+        // Iterate over all properties "key:value key:value ..."
+        for (;;) {
+            size_t token_len = strcspn(s, " ");
+            if (!token_len) {
+                break;
+            }
+            eol = s[token_len] == '\0';
+            s[token_len] = '\0';
+            char *token = s;
+
+            if (!strncmp("model:", token, sizeof("model:") - 1)) {
+                model = &token[sizeof("model:") - 1];
+                // We only need the model
+                break;
+            }
+
+            if (eol) {
+                break;
+            } else {
+                s+= token_len + 1;
+            }
+        }
+    }
+
+    device->serial = strdup(serial);
+    if (!device->serial) {
+        return false;
+    }
+
+    device->state = strdup(state);
+    if (!device->state) {
+        free(device->serial);
+        return false;
+    }
+
+    if (model) {
+        device->model = strdup(model);
+        if (!device->model) {
+            LOG_OOM();
+            // model is optional, do not fail
+        }
+    } else {
+        device->model = NULL;
+    }
+
+    device->selected = false;
+
+    return true;
+}
+
+ssize_t
+sc_adb_parse_devices(char *str, struct sc_adb_device *devices,
+                     size_t devices_len) {
+    size_t dev_count = 0;
+
+#define HEADER "List of devices attached"
+#define HEADER_LEN (sizeof(HEADER) - 1)
+    bool header_found = false;
+
+    size_t idx_line = 0;
+    while (str[idx_line] != '\0') {
+        char *line = &str[idx_line];
+        size_t len = strcspn(line, "\n");
+
+        // The next line starts after the '\n' (replaced by `\0`)
+        idx_line += len;
+
+        if (str[idx_line] != '\0') {
+            // The next line starts after the '\n'
+            ++idx_line;
+        }
+
+        if (!header_found) {
+            if (!strncmp(line, HEADER, HEADER_LEN)) {
+                header_found = true;
+            }
+            // Skip everything until the header, there might be garbage lines
+            // related to daemon starting before
+            continue;
+        }
+
+        // The line, but without any trailing '\r'
+        size_t line_len = sc_str_remove_trailing_cr(line, len);
+        line[line_len] = '\0';
+
+        bool ok = sc_adb_parse_device(line, &devices[dev_count]);
+        if (!ok) {
+            continue;
+        }
+
+        ++dev_count;
+
+        assert(dev_count <= devices_len);
+        if (dev_count == devices_len) {
+            // Max number of devices reached
+            break;
+        }
+    }
+
+    if (!header_found) {
+        return -1;
+    }
+
+    return dev_count;
+}
+
 static char *
 sc_adb_parse_device_ip_from_line(char *line) {
     // One line from "ip route" looks like:
@@ -64,7 +223,7 @@ sc_adb_parse_device_ip_from_output(char *str) {
 
         if (str[idx_line] != '\0') {
             // The next line starts after the '\n'
-            idx_line += 1;
+            ++idx_line;
         }
     }
 

app/src/adb/adb_parser.h

@@ -5,6 +5,19 @@
 
 #include <stddef.h>
 
+#include "adb_device.h"
+
+/**
+ * Parse the available devices from the output of `adb devices`
+ *
+ * The parameter must be a NUL-terminated string.
+ *
+ * Warning: this function modifies the buffer for optimization purposes.
+ */
+ssize_t
+sc_adb_parse_devices(char *str, struct sc_adb_device *devices,
+                     size_t devices_len);
+
 /**
  * Parse the ip from the output of `adb shell ip route`
  *

app/src/cli.c

@@ -416,6 +416,16 @@ static const struct sc_option options[] = {
                 "Default is 0 (not forced): the local port used for "
                 "establishing the tunnel will be used.",
     },
+    {
+        .shortopt = 'T',
+        .longopt = "select-tcpip",
+        .text = "Use TCP/IP device (if there is exactly one).",
+    },
+    {
+        .shortopt = 'U',
+        .longopt = "select-usb",
+        .text = "Use USB device (if there is exactly one).",
+    },
     {
         .longopt_id = OPT_V4L2_SINK,
         .longopt = "v4l2-sink",
@@ -1401,6 +1411,12 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case 't':
                 opts->show_touches = true;
                 break;
+            case 'T':
+                opts->select_tcpip = true;
+                break;
+            case 'U':
+                opts->select_usb = true;
+                break;
             case OPT_ALWAYS_ON_TOP:
                 opts->always_on_top = true;
                 break;
@@ -1559,8 +1575,16 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
     // If a TCP/IP address is provided, then tcpip must be enabled
     assert(opts->tcpip || !opts->tcpip_dst);
 
-    if (opts->serial && opts->tcpip_dst) {
+    unsigned selectors = !!opts->serial
-        LOGE("Incompatible options: -s/--serial and --tcpip with an argument");
+                       + !!opts->tcpip_dst
+                       + opts->select_tcpip
+                       + opts->select_usb;
+    if (selectors > 1) {
+        LOGE("At most one device selector option may be passed, among:\n"
+             "  --serial (-s)\n"
+             "  --select-usb (-U)\n"
+             "  --select-tcpip (-T)\n"
+             "  --tcpip=<addr> (with an argument)");
         return false;
     }
 

app/src/compat.h

@@ -8,8 +8,10 @@
 
 #ifndef __WIN32
 # define PRIu64_ PRIu64
+# define SC_PRIsizet "zu"
 #else
 # define PRIu64_ "I64u"  // Windows...
+# define SC_PRIsizet "Iu"
 #endif
 
 // In ffmpeg/doc/APIchanges:

app/src/controller.c

@@ -113,7 +113,7 @@ sc_controller_start(struct sc_controller *controller) {
     bool ok = sc_thread_create(&controller->thread, run_controller,
                                "scrcpy-ctl", controller);
     if (!ok) {
-        LOGC("Could not start controller thread");
+        LOGE("Could not start controller thread");
         return false;
     }
 

app/src/demuxer.c

@@ -276,7 +276,7 @@ sc_demuxer_start(struct sc_demuxer *demuxer) {
     bool ok = sc_thread_create(&demuxer->thread, run_demuxer, "scrcpy-demuxer",
                                demuxer);
     if (!ok) {
-        LOGC("Could not start demuxer thread");
+        LOGE("Could not start demuxer thread");
         return false;
     }
     return true;

app/src/file_pusher.c

@@ -156,7 +156,7 @@ sc_file_pusher_start(struct sc_file_pusher *fp) {
 
     bool ok = sc_thread_create(&fp->thread, run_file_pusher, "scrcpy-file", fp);
     if (!ok) {
-        LOGC("Could not start file_pusher thread");
+        LOGE("Could not start file_pusher thread");
         return false;
     }
 

app/src/options.c

@@ -60,4 +60,6 @@ const struct scrcpy_options scrcpy_options_default = {
     .downsize_on_error = true,
     .tcpip = false,
     .tcpip_dst = NULL,
+    .select_tcpip = false,
+    .select_usb = false,
 };

app/src/options.h

@@ -135,6 +135,8 @@ struct scrcpy_options {
     bool downsize_on_error;
     bool tcpip;
     const char *tcpip_dst;
+    bool select_usb;
+    bool select_tcpip;
 };
 
 extern const struct scrcpy_options scrcpy_options_default;

app/src/receiver.c

@@ -114,7 +114,7 @@ receiver_start(struct receiver *receiver) {
     bool ok = sc_thread_create(&receiver->thread, run_receiver,
                                "scrcpy-receiver", receiver);
     if (!ok) {
-        LOGC("Could not start receiver thread");
+        LOGE("Could not start receiver thread");
         return false;
     }
 

app/src/recorder.c

@@ -290,7 +290,7 @@ sc_recorder_open(struct sc_recorder *recorder, const AVCodec *input_codec) {
     ok = sc_thread_create(&recorder->thread, run_recorder, "scrcpy-recorder",
                           recorder);
     if (!ok) {
-        LOGC("Could not start recorder thread");
+        LOGE("Could not start recorder thread");
         goto error_avio_close;
     }
 

app/src/scrcpy.c

@@ -269,7 +269,7 @@ scrcpy(struct scrcpy_options *options) {
 
     // Minimal SDL initialization
     if (SDL_Init(SDL_INIT_EVENTS)) {
-        LOGC("Could not initialize SDL: %s", SDL_GetError());
+        LOGE("Could not initialize SDL: %s", SDL_GetError());
         return false;
     }
 
@@ -297,6 +297,8 @@ scrcpy(struct scrcpy_options *options) {
 
     struct sc_server_params params = {
         .req_serial = options->serial,
+        .select_usb = options->select_usb,
+        .select_tcpip = options->select_tcpip,
         .log_level = options->log_level,
         .crop = options->crop,
         .port_range = options->port_range,
@@ -341,7 +343,7 @@ scrcpy(struct scrcpy_options *options) {
 
     // Initialize SDL video in addition if display is enabled
     if (options->display && SDL_Init(SDL_INIT_VIDEO)) {
-        LOGC("Could not initialize SDL: %s", SDL_GetError());
+        LOGE("Could not initialize SDL: %s", SDL_GetError());
         goto end;
     }
 
@@ -430,32 +432,19 @@ scrcpy(struct scrcpy_options *options) {
             }
 
             assert(serial);
-            struct sc_usb_device usb_devices[16];
+            struct sc_usb_device usb_device;
-            ssize_t count = sc_usb_find_devices(&s->usb, serial, usb_devices,
+            ok = sc_usb_select_device(&s->usb, serial, &usb_device);
-                                                ARRAY_LEN(usb_devices));
+            if (!ok) {
-            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.serial, usb_device.vid, usb_device.pid,
-                 usb_device->manufacturer, usb_device->product);
+                 usb_device.manufacturer, usb_device.product);
 
-            ok = sc_usb_connect(&s->usb, usb_device->device, NULL, NULL);
+            ok = sc_usb_connect(&s->usb, usb_device.device, NULL, NULL);
-            sc_usb_device_destroy(usb_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/screen.c

@@ -423,14 +423,14 @@ sc_screen_init(struct sc_screen *screen,
     screen->window =
         SDL_CreateWindow(params->window_title, 0, 0, 0, 0, window_flags);
     if (!screen->window) {
-        LOGC("Could not create window: %s", SDL_GetError());
+        LOGE("Could not create window: %s", SDL_GetError());
         goto error_destroy_fps_counter;
     }
 
     screen->renderer = SDL_CreateRenderer(screen->window, -1,
                                           SDL_RENDERER_ACCELERATED);
     if (!screen->renderer) {
-        LOGC("Could not create renderer: %s", SDL_GetError());
+        LOGE("Could not create renderer: %s", SDL_GetError());
         goto error_destroy_window;
     }
 
@@ -479,7 +479,7 @@ sc_screen_init(struct sc_screen *screen,
                                                   params->frame_size.height);
     screen->texture = create_texture(screen);
     if (!screen->texture) {
-        LOGC("Could not create texture: %s", SDL_GetError());
+        LOGE("Could not create texture: %s", SDL_GetError());
         goto error_destroy_renderer;
     }
 
@@ -666,7 +666,7 @@ prepare_for_frame(struct sc_screen *screen, struct sc_size new_frame_size) {
                      screen->frame_size.width, screen->frame_size.height);
         screen->texture = create_texture(screen);
         if (!screen->texture) {
-            LOGC("Could not create texture: %s", SDL_GetError());
+            LOGE("Could not create texture: %s", SDL_GetError());
             return false;
         }
     }

app/src/server.c

@@ -503,22 +503,6 @@ sc_server_on_terminated(void *userdata) {
     LOGD("Server terminated");
 }
 
-static char *
-sc_server_read_serial(struct sc_server *server) {
-    char *serial;
-    if (server->params.req_serial) {
-        // The serial is already known
-        serial = strdup(server->params.req_serial);
-        if (!serial) {
-            LOG_OOM();
-        }
-    } else {
-        serial = sc_adb_get_serialno(&server->intr, 0);
-    }
-
-    return serial;
-}
-
 static bool
 is_tcpip_mode_enabled(struct sc_server *server, const char *serial) {
     struct sc_intr *intr = &server->intr;
@@ -641,51 +625,34 @@ sc_server_connect_to_tcpip(struct sc_server *server, const char *ip_port) {
     return true;
 }
 
+static bool
+sc_server_configure_tcpip_known_address(struct sc_server *server,
+                                        const char *addr) {
+    // Append ":5555" if no port is present
+    bool contains_port = strchr(addr, ':');
+    char *ip_port = contains_port ? strdup(addr) : append_port_5555(addr);
+    if (!ip_port) {
+        LOG_OOM();
+        return false;
+    }
+
+    server->serial = ip_port;
+    return sc_server_connect_to_tcpip(server, ip_port);
+}
 
 static bool
-sc_server_configure_tcpip(struct sc_server *server) {
+sc_server_configure_tcpip_unknown_address(struct sc_server *server,
-    char *ip_port;
+                                          const char *serial) {
+    bool is_already_tcpip = sc_adb_is_serial_tcpip(serial);
+    if (is_already_tcpip) {
+        // Nothing to do
+        LOGI("Device already connected via TCP/IP: %s", serial);
+        return true;
+    }
 
-    const struct sc_server_params *params = &server->params;
+    char *ip_port = sc_server_switch_to_tcpip(server, serial);
-
+    if (!ip_port) {
-    // If tcpip parameter is given, then it must connect to this address.
+        return false;
-    // Therefore, the device is unknown, so serial is meaningless at this point.
-    assert(!params->req_serial || !params->tcpip_dst);
-
-    if (params->tcpip_dst) {
-        // Append ":5555" if no port is present
-        bool contains_port = strchr(params->tcpip_dst, ':');
-        ip_port = contains_port ? strdup(params->tcpip_dst)
-                                : append_port_5555(params->tcpip_dst);
-        if (!ip_port) {
-            LOG_OOM();
-            return false;
-        }
-    } else {
-        // The device IP address must be retrieved from the current
-        // connected device
-        char *serial = sc_server_read_serial(server);
-        if (!serial) {
-            LOGE("Could not get device serial");
-            return false;
-        }
-
-        // The serial is either the real serial when connected via USB, or
-        // the IP:PORT when connected over TCP/IP. Only the latter contains
-        // a colon.
-        bool is_already_tcpip = strchr(serial, ':');
-        if (is_already_tcpip) {
-            // Nothing to do
-            LOGI("Device already connected via TCP/IP: %s", serial);
-            free(serial);
-            return true;
-        }
-
-        ip_port = sc_server_switch_to_tcpip(server, serial);
-        free(serial);
-        if (!ip_port) {
-            return false;
-        }
     }
 
     server->serial = ip_port;
@@ -698,16 +665,69 @@ run_server(void *data) {
 
     const struct sc_server_params *params = &server->params;
 
-    if (params->tcpip) {
+    // Execute "adb start-server" before "adb devices" so that daemon starting
-        bool ok = sc_server_configure_tcpip(server);
+    // output/errors is correctly printed in the console ("adb devices" output
+    // is parsed, so it is not output)
+    bool ok = sc_adb_start_server(&server->intr, 0);
+    if (!ok) {
+        LOGE("Could not start adb daemon");
+        goto error_connection_failed;
+    }
+
+    // params->tcpip_dst implies params->tcpip
+    assert(!params->tcpip_dst || params->tcpip);
+
+    // If tcpip_dst parameter is given, then it must connect to this address.
+    // Therefore, the device is unknown, so serial is meaningless at this point.
+    assert(!params->req_serial || !params->tcpip_dst);
+
+    // A device must be selected via a serial in all cases except when --tcpip=
+    // is called with a parameter (in that case, the device may initially not
+    // exist, and scrcpy will execute "adb connect").
+    bool need_initial_serial = !params->tcpip_dst;
+
+    if (need_initial_serial) {
+        // At most one of the 3 following parameters may be set
+        assert(!!params->req_serial
+               + params->select_usb
+               + params->select_tcpip <= 1);
+
+        struct sc_adb_device_selector selector;
+        if (params->req_serial) {
+            selector.type = SC_ADB_DEVICE_SELECT_SERIAL;
+            selector.serial = params->req_serial;
+        } else if (params->select_usb) {
+            selector.type = SC_ADB_DEVICE_SELECT_USB;
+        } else if (params->select_tcpip) {
+            selector.type = SC_ADB_DEVICE_SELECT_TCPIP;
+        } else {
+            selector.type = SC_ADB_DEVICE_SELECT_ALL;
+        }
+        struct sc_adb_device device;
+        ok = sc_adb_select_device(&server->intr, &selector, 0, &device);
         if (!ok) {
             goto error_connection_failed;
         }
-        assert(server->serial);
+
+        if (params->tcpip) {
+            assert(!params->tcpip_dst);
+            ok = sc_server_configure_tcpip_unknown_address(server,
+                                                           device.serial);
+            sc_adb_device_destroy(&device);
+            if (!ok) {
+                goto error_connection_failed;
+            }
+            assert(server->serial);
+        } else {
+            // "move" the device.serial without copy
+            server->serial = device.serial;
+            // the serial must not be freed by the destructor
+            device.serial = NULL;
+            sc_adb_device_destroy(&device);
+        }
     } else {
-        server->serial = sc_server_read_serial(server);
+        ok = sc_server_configure_tcpip_known_address(server, params->tcpip_dst);
-        if (!server->serial) {
+        if (!ok) {
-            LOGD("Could not get device serial");
             goto error_connection_failed;
         }
     }
@@ -716,7 +736,7 @@ run_server(void *data) {
     assert(serial);
     LOGD("Device serial: %s", serial);
 
-    bool ok = push_server(&server->intr, serial);
+    ok = push_server(&server->intr, serial);
     if (!ok) {
         goto error_connection_failed;
     }

app/src/server.h

@@ -44,6 +44,8 @@ struct sc_server_params {
     bool downsize_on_error;
     bool tcpip;
     const char *tcpip_dst;
+    bool select_usb;
+    bool select_tcpip;
 };
 
 struct sc_server {

app/src/sys/unix/process.c

@@ -176,7 +176,7 @@ sc_process_execute_p(const char *const argv[], sc_pid *pid, unsigned flags,
 bool
 sc_process_terminate(pid_t pid) {
     if (pid <= 0) {
-        LOGC("Requested to kill %d, this is an error. Please report the bug.\n",
+        LOGE("Requested to kill %d, this is an error. Please report the bug.\n",
              (int) pid);
         abort();
     }

app/src/usb/aoa_hid.c

@@ -278,7 +278,7 @@ sc_aoa_start(struct sc_aoa *aoa) {
 
     bool ok = sc_thread_create(&aoa->thread, run_aoa_thread, "scrcpy-aoa", aoa);
     if (!ok) {
-        LOGC("Could not start AOA thread");
+        LOGE("Could not start AOA thread");
         return false;
     }
 

app/src/usb/scrcpy_otg.c

@@ -56,7 +56,7 @@ scrcpy_otg(struct scrcpy_options *options) {
 
     // Minimal SDL initialization
     if (SDL_Init(SDL_INIT_EVENTS)) {
-        LOGC("Could not initialize SDL: %s", SDL_GetError());
+        LOGE("Could not initialize SDL: %s", SDL_GetError());
         return false;
     }
 
@@ -83,50 +83,17 @@ scrcpy_otg(struct scrcpy_options *options) {
         return false;
     }
 
-    struct sc_usb_device usb_devices[16];
+    struct sc_usb_device usb_device;
-    ssize_t count = sc_usb_find_devices(&s->usb, serial, usb_devices,
+    ok = sc_usb_select_device(&s->usb, serial, &usb_device);
-                                        ARRAY_LEN(usb_devices));
+    if (!ok) {
-    if (count < 0) {
-        LOGE("Could not list USB devices");
         goto end;
     }
 
-    if (count == 0) {
+    LOGI("USB device: %s (%04x:%04x) %s %s", usb_device.serial,
-        if (serial) {
+         (unsigned) usb_device.vid, (unsigned) usb_device.pid,
-            LOGE("Could not find USB device %s", serial);
+         usb_device.manufacturer, usb_device.product);
-        } else {
-            LOGE("Could not find any USB device");
-        }
-        goto end;
-    }
 
-    if (count > 1) {
+    ok = sc_usb_connect(&s->usb, usb_device.device, &cbs, NULL);
-        if (serial) {
-            LOGE("Multiple (%d) USB devices with serial %s:", (int) count,
-                 serial);
-        } else {
-            LOGE("Multiple (%d) USB devices:", (int) count);
-        }
-        for (size_t i = 0; i < (size_t) count; ++i) {
-            struct sc_usb_device *d = &usb_devices[i];
-            LOGE("    %-18s (%04" PRIx16 ":%04" PRIx16 ")  %s %s",
-                 d->serial, d->vid, d->pid, d->manufacturer, d->product);
-        }
-        if (!serial) {
-            LOGE("Specify the device via -s or --serial");
-        }
-        sc_usb_device_destroy_all(usb_devices, count);
-        goto end;
-    }
-    usb_device_initialized = true;
-
-    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);
-
-    ok = sc_usb_connect(&s->usb, usb_device->device, &cbs, NULL);
     if (!ok) {
         goto end;
     }
@@ -173,7 +140,7 @@ scrcpy_otg(struct scrcpy_options *options) {
 
     const char *window_title = options->window_title;
     if (!window_title) {
-        window_title = usb_device->product ? usb_device->product : "scrcpy";
+        window_title = usb_device.product ? usb_device.product : "scrcpy";
     }
 
     struct sc_screen_otg_params params = {
@@ -192,7 +159,7 @@ scrcpy_otg(struct scrcpy_options *options) {
     }
 
     // usb_device not needed anymore
-    sc_usb_device_destroy(usb_device);
+    sc_usb_device_destroy(&usb_device);
     usb_device_initialized = false;
 
     ret = event_loop(s);
@@ -223,7 +190,7 @@ end:
     }
 
     if (usb_device_initialized) {
-        sc_usb_device_destroy(usb_device);
+        sc_usb_device_destroy(&usb_device);
     }
 
     sc_usb_destroy(&s->usb);

app/src/usb/usb.c

@@ -25,8 +25,7 @@ read_string(libusb_device_handle *handle, uint8_t desc_index) {
 }
 
 static bool
-accept_device(libusb_device *device, const char *serial,
+sc_usb_read_device(libusb_device *device, struct sc_usb_device *out) {
-              struct sc_usb_device *out) {
     // Do not log any USB error in this function, it is expected that many USB
     // devices available on the computer have permission restrictions
 
@@ -39,6 +38,11 @@ accept_device(libusb_device *device, const char *serial,
     libusb_device_handle *handle;
     result = libusb_open(device, &handle);
     if (result < 0) {
+        // Log at debug level because it is expected that some non-Android USB
+        // devices present on the computer require special permissions
+        LOGD("Open USB device %04x:%04x: libusb error: %s",
+             (unsigned) desc.idVendor, (unsigned) desc.idProduct,
+             libusb_strerror(result));
         return false;
     }
 
@@ -48,22 +52,13 @@ accept_device(libusb_device *device, const char *serial,
         return false;
     }
 
-    if (serial) {
-        // Filter by serial
-        bool matches = !strcmp(serial, device_serial);
-        if (!matches) {
-            free(device_serial);
-            libusb_close(handle);
-            return false;
-        }
-    }
-
     out->device = libusb_ref_device(device);
     out->serial = device_serial;
     out->vid = desc.idVendor;
     out->pid = desc.idProduct;
     out->manufacturer = read_string(handle, desc.iManufacturer);
     out->product = read_string(handle, desc.iProduct);
+    out->selected = false;
 
     libusb_close(handle);
 
@@ -72,22 +67,33 @@ accept_device(libusb_device *device, const char *serial,
 
 void
 sc_usb_device_destroy(struct sc_usb_device *usb_device) {
-    libusb_unref_device(usb_device->device);
+    if (usb_device->device) {
+        libusb_unref_device(usb_device->device);
+    }
     free(usb_device->serial);
     free(usb_device->manufacturer);
     free(usb_device->product);
 }
 
 void
-sc_usb_device_destroy_all(struct sc_usb_device *usb_devices, size_t count) {
+sc_usb_device_move(struct sc_usb_device *dst, struct sc_usb_device *src) {
+    *dst = *src;
+    src->device = NULL;
+    src->serial = NULL;
+    src->manufacturer = NULL;
+    src->product = NULL;
+}
+
+void
+sc_usb_devices_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
+static ssize_t
-sc_usb_find_devices(struct sc_usb *usb, const char *serial,
+sc_usb_list_devices(struct sc_usb *usb, struct sc_usb_device *devices,
-                    struct sc_usb_device *devices, size_t len) {
+                    size_t len) {
     libusb_device **list;
     ssize_t count = libusb_get_device_list(usb->context, &list);
     if (count < 0) {
@@ -99,7 +105,7 @@ sc_usb_find_devices(struct sc_usb *usb, const char *serial,
     for (size_t i = 0; i < (size_t) count && idx < len; ++i) {
         libusb_device *device = list[i];
 
-        if (accept_device(device, serial, &devices[idx])) {
+        if (sc_usb_read_device(device, &devices[idx])) {
             ++idx;
         }
     }
@@ -108,6 +114,102 @@ sc_usb_find_devices(struct sc_usb *usb, const char *serial,
     return idx;
 }
 
+static bool
+sc_usb_accept_device(const struct sc_usb_device *device, const char *serial) {
+    if (!serial) {
+        return true;
+    }
+
+    return !strcmp(serial, device->serial);
+}
+
+static size_t
+sc_usb_devices_select(struct sc_usb_device *devices, size_t len,
+                      const char *serial, size_t *idx_out) {
+    size_t count = 0;
+    for (size_t i = 0; i < len; ++i) {
+        struct sc_usb_device *device = &devices[i];
+        device->selected = sc_usb_accept_device(device, serial);
+        if (device->selected) {
+            if (idx_out && !count) {
+                *idx_out = i;
+            }
+            ++count;
+        }
+    }
+
+    return count;
+}
+
+static void
+sc_usb_devices_log(enum sc_log_level level, struct sc_usb_device *devices,
+                   size_t count) {
+    for (size_t i = 0; i < count; ++i) {
+        struct sc_usb_device *d = &devices[i];
+        const char *selection = d->selected ? "-->" : "   ";
+        // Convert uint16_t to unsigned because PRIx16 may not exist on Windows
+        LOG(level, "    %s %-18s (%04x:%04x)  %s %s",
+            selection, d->serial, (unsigned) d->vid, (unsigned) d->pid,
+            d->manufacturer, d->product);
+    }
+}
+
+bool
+sc_usb_select_device(struct sc_usb *usb, const char *serial,
+                     struct sc_usb_device *out_device) {
+    struct sc_usb_device usb_devices[16];
+    ssize_t count =
+        sc_usb_list_devices(usb, usb_devices, ARRAY_LEN(usb_devices));
+    if (count == -1) {
+        LOGE("Could not list USB devices");
+        return false;
+    }
+
+    if (count == 0) {
+        LOGE("Could not find any USB device");
+        return false;
+    }
+
+    size_t sel_idx; // index of the single matching device if sel_count == 1
+    size_t sel_count =
+        sc_usb_devices_select(usb_devices, count, serial, &sel_idx);
+
+    if (sel_count == 0) {
+        // if count > 0 && sel_count == 0, then necessarily a serial is provided
+        assert(serial);
+        LOGE("Could not find USB device %s", serial);
+        sc_usb_devices_log(SC_LOG_LEVEL_ERROR, usb_devices, count);
+        sc_usb_devices_destroy_all(usb_devices, count);
+        return false;
+    }
+
+    if (sel_count > 1) {
+        if (serial) {
+            LOGE("Multiple (%" SC_PRIsizet ") USB devices with serial %s:",
+                 sel_count, serial);
+        } else {
+            LOGE("Multiple (%" SC_PRIsizet ") USB devices:", sel_count);
+        }
+        sc_usb_devices_log(SC_LOG_LEVEL_ERROR, usb_devices, count);
+        if (!serial) {
+            LOGE("Specify the device via -s or --serial");
+        }
+        sc_usb_devices_destroy_all(usb_devices, count);
+        return false;
+    }
+
+    assert(sel_count == 1); // sel_idx is valid only if sel_count == 1
+    struct sc_usb_device *device = &usb_devices[sel_idx];
+
+    LOGD("USB device found:");
+    sc_usb_devices_log(SC_LOG_LEVEL_DEBUG, usb_devices, count);
+
+    // Move device into out_device (do not destroy device)
+    sc_usb_device_move(out_device, device);
+    sc_usb_devices_destroy_all(usb_devices, count);
+    return true;
+}
+
 bool
 sc_usb_init(struct sc_usb *usb) {
     usb->handle = NULL;
@@ -119,7 +221,7 @@ sc_usb_destroy(struct sc_usb *usb) {
     libusb_exit(usb->context);
 }
 
-static int
+static LIBUSB_CALL int
 sc_usb_libusb_callback(libusb_context *ctx, libusb_device *device,
                        libusb_hotplug_event event, void *userdata) {
     (void) ctx;

app/src/usb/usb.h

@@ -35,13 +35,26 @@ struct sc_usb_device {
     char *product;
     uint16_t vid;
     uint16_t pid;
+    bool selected;
 };
 
 void
 sc_usb_device_destroy(struct sc_usb_device *usb_device);
 
+/**
+ * Move src to dest
+ *
+ * After this call, the content of src is undefined, except that
+ * sc_usb_device_destroy() can be called.
+ *
+ * This is useful to take a device from a list that will be destroyed, without
+ * making unnecessary copies.
+ */
 void
-sc_usb_device_destroy_all(struct sc_usb_device *usb_devices, size_t count);
+sc_usb_device_move(struct sc_usb_device *dst, struct sc_usb_device *src);
+
+void
+sc_usb_devices_destroy_all(struct sc_usb_device *usb_devices, size_t count);
 
 bool
 sc_usb_init(struct sc_usb *usb);
@@ -49,9 +62,9 @@ sc_usb_init(struct sc_usb *usb);
 void
 sc_usb_destroy(struct sc_usb *usb);
 
-ssize_t
+bool
-sc_usb_find_devices(struct sc_usb *usb, const char *serial,
+sc_usb_select_device(struct sc_usb *usb, const char *serial,
-                    struct sc_usb_device *devices, size_t len);
+                     struct sc_usb_device *out_device);
 
 bool
 sc_usb_connect(struct sc_usb *usb, libusb_device *device,

app/src/util/log.c

@@ -55,6 +55,16 @@ sc_get_log_level(void) {
     return log_level_sdl_to_sc(sdl_log);
 }
 
+void
+sc_log(enum sc_log_level level, const char *fmt, ...) {
+    SDL_LogPriority sdl_level = log_level_sc_to_sdl(level);
+
+    va_list ap;
+    va_start(ap, fmt);
+    SDL_LogMessageV(SDL_LOG_CATEGORY_APPLICATION, sdl_level, fmt, ap);
+    va_end(ap);
+}
+
 #ifdef _WIN32
 bool
 sc_log_windows_error(const char *prefix, int error) {

app/src/util/log.h

@@ -15,10 +15,9 @@
 #define LOGI(...) SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)
 #define LOGW(...) SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)
 #define LOGE(...) SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)
-#define LOGC(...) SDL_LogCritical(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)
 
 #define LOG_OOM() \
-    LOGC("OOM: %s:%d %s()", __FILE__, __LINE__, __func__)
+    LOGE("OOM: %s:%d %s()", __FILE__, __LINE__, __func__)
 
 void
 sc_set_log_level(enum sc_log_level level);
@@ -26,6 +25,10 @@ sc_set_log_level(enum sc_log_level level);
 enum sc_log_level
 sc_get_log_level(void);
 
+void
+sc_log(enum sc_log_level level, const char *fmt, ...);
+#define LOG(LEVEL, ...) sc_log((LEVEL), __VA_ARGS__)
+
 #ifdef _WIN32
 // Log system error (typically returned by GetLastError() or similar)
 bool

app/src/util/net.c

@@ -33,7 +33,7 @@ net_init(void) {
     WSADATA wsa;
     int res = WSAStartup(MAKEWORD(2, 2), &wsa) < 0;
     if (res < 0) {
-        LOGC("WSAStartup failed with error %d", res);
+        LOGE("WSAStartup failed with error %d", res);
         return false;
     }
 #endif

app/src/util/process.h

@@ -12,8 +12,6 @@
 # include <winsock2.h>
 # include <windows.h>
 # define SC_PRIexitcode "lu"
-// <https://stackoverflow.com/a/44383330/1987178>
-# define SC_PRIsizet "Iu"
 # define SC_PROCESS_NONE NULL
 # define SC_EXIT_CODE_NONE -1UL // max value as unsigned long
   typedef HANDLE sc_pid;
@@ -23,7 +21,6 @@
 #else
 
 # include <sys/types.h>
-# define SC_PRIsizet "zu"
 # define SC_PRIexitcode "d"
 # define SC_PROCESS_NONE -1
 # define SC_EXIT_CODE_NONE -1

app/src/util/thread.c

@@ -54,7 +54,7 @@ sc_mutex_lock(sc_mutex *mutex) {
     int r = SDL_LockMutex(mutex->mutex);
 #ifndef NDEBUG
     if (r) {
-        LOGC("Could not lock mutex: %s", SDL_GetError());
+        LOGE("Could not lock mutex: %s", SDL_GetError());
         abort();
     }
 
@@ -74,7 +74,7 @@ sc_mutex_unlock(sc_mutex *mutex) {
     int r = SDL_UnlockMutex(mutex->mutex);
 #ifndef NDEBUG
     if (r) {
-        LOGC("Could not lock mutex: %s", SDL_GetError());
+        LOGE("Could not lock mutex: %s", SDL_GetError());
         abort();
     }
 #else
@@ -118,7 +118,7 @@ sc_cond_wait(sc_cond *cond, sc_mutex *mutex) {
     int r = SDL_CondWait(cond->cond, mutex->mutex);
 #ifndef NDEBUG
     if (r) {
-        LOGC("Could not wait on condition: %s", SDL_GetError());
+        LOGE("Could not wait on condition: %s", SDL_GetError());
         abort();
     }
 
@@ -140,7 +140,7 @@ sc_cond_timedwait(sc_cond *cond, sc_mutex *mutex, sc_tick deadline) {
     int r = SDL_CondWaitTimeout(cond->cond, mutex->mutex, ms);
 #ifndef NDEBUG
     if (r < 0) {
-        LOGC("Could not wait on condition with timeout: %s", SDL_GetError());
+        LOGE("Could not wait on condition with timeout: %s", SDL_GetError());
         abort();
     }
 
@@ -156,7 +156,7 @@ sc_cond_signal(sc_cond *cond) {
     int r = SDL_CondSignal(cond->cond);
 #ifndef NDEBUG
     if (r) {
-        LOGC("Could not signal a condition: %s", SDL_GetError());
+        LOGE("Could not signal a condition: %s", SDL_GetError());
         abort();
     }
 #else
@@ -169,7 +169,7 @@ sc_cond_broadcast(sc_cond *cond) {
     int r = SDL_CondBroadcast(cond->cond);
 #ifndef NDEBUG
     if (r) {
-        LOGC("Could not broadcast a condition: %s", SDL_GetError());
+        LOGE("Could not broadcast a condition: %s", SDL_GetError());
         abort();
     }
 #else

app/src/v4l2_sink.c

@@ -274,7 +274,7 @@ sc_v4l2_sink_open(struct sc_v4l2_sink *vs) {
     LOGD("Starting v4l2 thread");
     ok = sc_thread_create(&vs->thread, run_v4l2_sink, "scrcpy-v4l2", vs);
     if (!ok) {
-        LOGC("Could not start v4l2 thread");
+        LOGE("Could not start v4l2 thread");
         goto error_av_packet_free;
     }
 

app/tests/test_adb_parser.c

@@ -2,8 +2,158 @@
 
 #include <assert.h>
 
+#include "adb/adb_device.h"
 #include "adb/adb_parser.h"
 
+static void test_adb_devices() {
+    char output[] =
+        "List of devices attached\n"
+        "0123456789abcdef	device usb:2-1 product:MyProduct model:MyModel "
+            "device:MyDevice transport_id:1\n"
+        "192.168.1.1:5555	device product:MyWifiProduct model:MyWifiModel "
+            "device:MyWifiDevice trandport_id:2\n";
+
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 2);
+
+    struct sc_adb_device *device = &devices[0];
+    assert(!strcmp("0123456789abcdef", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyModel", device->model));
+
+    device = &devices[1];
+    assert(!strcmp("192.168.1.1:5555", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyWifiModel", device->model));
+
+    sc_adb_devices_destroy_all(devices, count);
+}
+
+static void test_adb_devices_cr() {
+    char output[] =
+        "List of devices attached\r\n"
+        "0123456789abcdef	device usb:2-1 product:MyProduct model:MyModel "
+            "device:MyDevice transport_id:1\r\n"
+        "192.168.1.1:5555	device product:MyWifiProduct model:MyWifiModel "
+            "device:MyWifiDevice trandport_id:2\r\n";
+
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 2);
+
+    struct sc_adb_device *device = &devices[0];
+    assert(!strcmp("0123456789abcdef", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyModel", device->model));
+
+    device = &devices[1];
+    assert(!strcmp("192.168.1.1:5555", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyWifiModel", device->model));
+
+    sc_adb_devices_destroy_all(devices, count);
+}
+
+static void test_adb_devices_daemon_start() {
+    char output[] =
+        "* daemon not running; starting now at tcp:5037\n"
+        "* daemon started successfully\n"
+        "List of devices attached\n"
+        "0123456789abcdef	device usb:2-1 product:MyProduct model:MyModel "
+            "device:MyDevice transport_id:1\n";
+
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 1);
+
+    struct sc_adb_device *device = &devices[0];
+    assert(!strcmp("0123456789abcdef", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyModel", device->model));
+
+    sc_adb_device_destroy(device);
+}
+
+static void test_adb_devices_daemon_start_mixed() {
+    char output[] =
+        "List of devices attached\n"
+        "adb server version (41) doesn't match this client (39); killing...\n"
+        "* daemon started successfully *\n"
+        "0123456789abcdef	unauthorized usb:1-1\n"
+        "87654321	device usb:2-1 product:MyProduct model:MyModel "
+            "device:MyDevice\n";
+
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 2);
+
+    struct sc_adb_device *device = &devices[0];
+    assert(!strcmp("0123456789abcdef", device->serial));
+    assert(!strcmp("unauthorized", device->state));
+    fprintf(stderr, "==== [%s]\n", device->model);
+    assert(!device->model);
+
+    device = &devices[1];
+    assert(!strcmp("87654321", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyModel", device->model));
+
+    sc_adb_devices_destroy_all(devices, count);
+}
+
+static void test_adb_devices_without_eol() {
+    char output[] =
+        "List of devices attached\n"
+        "0123456789abcdef	device usb:2-1 product:MyProduct model:MyModel "
+            "device:MyDevice transport_id:1";
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 1);
+
+    struct sc_adb_device *device = &devices[0];
+    assert(!strcmp("0123456789abcdef", device->serial));
+    assert(!strcmp("device", device->state));
+    assert(!strcmp("MyModel", device->model));
+
+    sc_adb_device_destroy(device);
+}
+
+static void test_adb_devices_without_header() {
+    char output[] =
+        "0123456789abcdef	device usb:2-1 product:MyProduct model:MyModel "
+            "device:MyDevice transport_id:1\n";
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == -1);
+}
+
+static void test_adb_devices_corrupted() {
+    char output[] =
+        "List of devices attached\n"
+        "corrupted_garbage\n";
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 0);
+}
+
+static void test_adb_devices_spaces() {
+    char output[] =
+        "List of devices attached\n"
+        "0123456789abcdef       unauthorized usb:1-4 transport_id:3\n";
+
+    struct sc_adb_device devices[16];
+    ssize_t count = sc_adb_parse_devices(output, devices, ARRAY_LEN(devices));
+    assert(count == 1);
+
+    struct sc_adb_device *device = &devices[0];
+    assert(!strcmp("0123456789abcdef", device->serial));
+    assert(!strcmp("unauthorized", device->state));
+    assert(!device->model);
+
+    sc_adb_device_destroy(device);
+}
+
 static void test_get_ip_single_line() {
     char ip_route[] = "192.168.1.0/24 dev wlan0  proto kernel  scope link  src "
                       "192.168.12.34\r\r\n";
@@ -86,6 +236,15 @@ int main(int argc, char *argv[]) {
     (void) argc;
     (void) argv;
 
+    test_adb_devices();
+    test_adb_devices_cr();
+    test_adb_devices_daemon_start();
+    test_adb_devices_daemon_start_mixed();
+    test_adb_devices_without_eol();
+    test_adb_devices_without_header();
+    test_adb_devices_corrupted();
+    test_adb_devices_spaces();
+
     test_get_ip_single_line();
     test_get_ip_single_line_without_eol();
     test_get_ip_single_line_with_trailing_space();

cross_win32.txt

@@ -21,3 +21,5 @@ ffmpeg_avformat = 'avformat-58'
 ffmpeg_avutil = 'avutil-56'
 prebuilt_ffmpeg = 'ffmpeg-win32-4.3.1'
 prebuilt_sdl2 = 'SDL2-2.0.20/i686-w64-mingw32'
+prebuilt_libusb_root = 'libusb-1.0.25'
+prebuilt_libusb = prebuilt_libusb_root + '/MinGW32'

cross_win64.txt

@@ -21,3 +21,5 @@ ffmpeg_avformat = 'avformat-59'
 ffmpeg_avutil = 'avutil-57'
 prebuilt_ffmpeg = 'ffmpeg-win64-5.0'
 prebuilt_sdl2 = 'SDL2-2.0.20/x86_64-w64-mingw32'
+prebuilt_libusb_root = 'libusb-1.0.25'
+prebuilt_libusb = prebuilt_libusb_root + '/MinGW64'

prebuilt-deps/prepare-libusb.sh

@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+set -e
+DIR=$(dirname ${BASH_SOURCE[0]})
+cd "$DIR"
+. common
+mkdir -p "$PREBUILT_DATA_DIR"
+cd "$PREBUILT_DATA_DIR"
+
+DEP_DIR=libusb-1.0.25
+
+FILENAME=libusb-1.0.25.7z
+SHA256SUM=3d1c98416f454026034b2b5d67f8a294053898cb70a8b489874e75b136c6674d
+
+if [[ -d "$DEP_DIR" ]]
+then
+    echo "$DEP_DIR" found
+    exit 0
+fi
+
+get_file "https://github.com/libusb/libusb/releases/download/v1.0.25/$FILENAME" "$FILENAME" "$SHA256SUM"
+
+mkdir "$DEP_DIR"
+cd "$DEP_DIR"
+
+7z x "../$FILENAME" \
+    MinGW32/dll/libusb-1.0.dll \
+    MinGW64/dll/libusb-1.0.dll \
+    include /

release.mk

@@ -66,6 +66,7 @@ prepare-deps-win32:
 	@prebuilt-deps/prepare-adb.sh
 	@prebuilt-deps/prepare-sdl.sh
 	@prebuilt-deps/prepare-ffmpeg-win32.sh
+	@prebuilt-deps/prepare-libusb.sh
 
 build-win32: prepare-deps-win32
 	[ -d "$(WIN32_BUILD_DIR)" ] || ( mkdir "$(WIN32_BUILD_DIR)" && \
@@ -107,6 +108,7 @@ dist-win32: build-server build-win32
 	cp prebuilt-deps/data/platform-tools-31.0.3/AdbWinApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
 	cp prebuilt-deps/data/platform-tools-31.0.3/AdbWinUsbApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
 	cp prebuilt-deps/data/SDL2-2.0.20/i686-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/data/libusb-1.0.25/MinGW32/dll/libusb-1.0.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
 
 dist-win64: build-server build-win64
 	mkdir -p "$(DIST)/$(WIN64_TARGET_DIR)"
@@ -125,6 +127,7 @@ dist-win64: build-server build-win64
 	cp prebuilt-deps/data/platform-tools-31.0.3/AdbWinApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
 	cp prebuilt-deps/data/platform-tools-31.0.3/AdbWinUsbApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
 	cp prebuilt-deps/data/SDL2-2.0.20/x86_64-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/data/libusb-1.0.25/MinGW64/dll/libusb-1.0.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
 
 zip-win32: dist-win32
 	cd "$(DIST)/$(WIN32_TARGET_DIR)"; \