Determine debugger command at runtime

When server_debugger is enabled, retrieve the device SDK version to
execute the correct command.

PR #5466 <https://github.com/Genymobile/scrcpy/pull/5466>

app/meson.build

@@ -167,9 +167,6 @@ conf.set('DEFAULT_LOCAL_PORT_RANGE_LAST', '27199')
 # run a server debugger and wait for a client to be attached
 conf.set('SERVER_DEBUGGER', get_option('server_debugger'))
 
-# select the debugger method ('old' for Android < 9, 'new' for Android >= 9)
-conf.set('SERVER_DEBUGGER_METHOD_NEW', get_option('server_debugger_method') == 'new')
-
 # enable V4L2 support (linux only)
 conf.set('HAVE_V4L2', v4l2_support)
 

app/src/adb/adb.c

@@ -739,3 +739,21 @@ sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags) {
 
     return sc_adb_parse_device_ip(buf);
 }
+
+uint16_t
+sc_adb_get_device_sdk_version(struct sc_intr *intr, const char *serial) {
+    char *sdk_version =
+        sc_adb_getprop(intr, serial, "ro.build.version.sdk", SC_ADB_SILENT);
+    if (!sdk_version) {
+        return 0;
+    }
+
+    long value;
+    bool ok = sc_str_parse_integer(sdk_version, &value);
+    free(sdk_version);
+    if (!ok || value < 0 || value > 0xFFFF) {
+        return 0;
+    }
+
+    return value;
+}

app/src/adb/adb.h

@@ -114,4 +114,10 @@ sc_adb_getprop(struct sc_intr *intr, const char *serial, const char *prop,
 char *
 sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags);
 
+/**
+ * Return the device SDK version.
+ */
+uint16_t
+sc_adb_get_device_sdk_version(struct sc_intr *intr, const char *serial);
+
 #endif

app/src/server.c

@@ -201,18 +201,26 @@ execute_server(struct sc_server *server,
     cmd[count++] = "app_process";
 
 #ifdef SERVER_DEBUGGER
+    uint16_t sdk_version = sc_adb_get_device_sdk_version(&server->intr, serial);
+    if (!sdk_version) {
+        LOGE("Could not determine SDK version");
+        return 0;
+    }
+
 # define SERVER_DEBUGGER_PORT "5005"
-    cmd[count++] =
+    const char *dbg;
-# ifdef SERVER_DEBUGGER_METHOD_NEW
+    if (sdk_version < 28) {
-        /* Android 9 and above */
+        // Android < 9
-        "-XjdwpProvider:internal -XjdwpOptions:transport=dt_socket,suspend=y,"
+        dbg = "-agentlib:jdwp=transport=dt_socket,suspend=y,server=y,address="
-        "server=y,address="
-# else
-        /* Android 8 and below */
-        "-agentlib:jdwp=transport=dt_socket,suspend=y,server=y,address="
-# endif
               SERVER_DEBUGGER_PORT;
+    } else {
+        // Android >= 9
+        dbg = "-XjdwpProvider:internal -XjdwpOptions:transport=dt_socket,"
+              "suspend=y,server=y,address=" SERVER_DEBUGGER_PORT;
+    }
+    cmd[count++] = dbg;
 #endif
+
     cmd[count++] = "/"; // unused
     cmd[count++] = "com.genymobile.scrcpy.Server";
     cmd[count++] = SCRCPY_VERSION;

doc/develop.md

@@ -461,15 +461,6 @@ meson setup x -Dserver_debugger=true
 meson configure x -Dserver_debugger=true
 ```
 
-If your device runs Android 8 or below, set the `server_debugger_method` to
-`old` in addition:
-
-```bash
-meson setup x -Dserver_debugger=true -Dserver_debugger_method=old
-# or, if x is already configured
-meson configure x -Dserver_debugger=true -Dserver_debugger_method=old
-```
-
 Then recompile.
 
 When you start scrcpy, it will start a debugger on port 5005 on the device.

meson_options.txt

@@ -3,6 +3,5 @@ option('compile_server', type: 'boolean', value: true, description: 'Build the s
 option('prebuilt_server', type: 'string', description: 'Path of the prebuilt server')
 option('portable', type: 'boolean', value: false, description: 'Use scrcpy-server from the same directory as the scrcpy executable')
 option('server_debugger', type: 'boolean', value: false, description: 'Run a server debugger and wait for a client to be attached')
-option('server_debugger_method', type: 'combo', choices: ['old', 'new'], value: 'new', description: 'Select the debugger method (Android < 9: "old", Android >= 9: "new")')
 option('v4l2', type: 'boolean', value: true, description: 'Enable V4L2 feature when supported')
 option('usb', type: 'boolean', value: true, description: 'Enable HID/OTG features when supported')