Add --prefer-text option

Expose an option to configure how key/text events are forwarded to the
Android device.

Enabling the option avoids issues when combining multiple keys to enter
special characters, but breaks the expected behavior of alpha keys in
games (typically WASD).

Fixes <https://github.com/Genymobile/scrcpy/issues/650>

README.md

@@ -143,7 +143,6 @@ This is useful for example to mirror only one eye of the Oculus Go:
 
 ```bash
 scrcpy --crop 1224:1440:0:0   # 1224x1440 at offset (0,0)
-scrcpy -c 1224:1440:0:0       # short version
 ```
 
 If `--max-size` is also specified, resizing is applied after cropping.
@@ -226,7 +225,6 @@ The window of app can always be above others by:
 
 ```bash
 scrcpy --always-on-top
-scrcpy -T  # short version
 ```
 
 

app/scrcpy.1

@@ -62,14 +62,11 @@ Set the TCP port the client listens on.
 Default is 27183.
 
 .TP
-.BI \-\-prefer\-text\-events " mode
-Configure how key/text events are forwarded to the Android device.
+.B \-\-prefer\-text
+Inject alpha characters and space as text events instead of key events.
 
-Possible \fImode\fRs are "always" (every text is sent as text), "non-alpha"
-(only letters are sent as a sequence of key events, other characters are sent
-as text) and "never" (every text is sent as a sequence of key events).
-
-Default is "always".
+This avoids issues when combining multiple keys to enter special characters,
+but breaks the expected behavior of alpha keys in games (typically WASD).
 
 .TP
 .BI "\-\-push\-target " path

app/src/event_converter.c

@@ -76,7 +76,7 @@ convert_meta_state(SDL_Keymod mod) {
 
 bool
 convert_keycode(SDL_Keycode from, enum android_keycode *to, uint16_t mod,
-                enum text_events_pref pref) {
+                bool prefer_text) {
     switch (from) {
         MAP(SDLK_RETURN,       AKEYCODE_ENTER);
         MAP(SDLK_KP_ENTER,     AKEYCODE_NUMPAD_ENTER);
@@ -94,15 +94,11 @@ convert_keycode(SDL_Keycode from, enum android_keycode *to, uint16_t mod,
         MAP(SDLK_UP,           AKEYCODE_DPAD_UP);
     }
 
-    if (pref == PREFER_TEXT_EVENTS_ALWAYS) {
-        // never forward key events
+    if (prefer_text) {
+        // do not forward alpha and space key events
         return false;
     }
 
-    // forward all supported key events
-    SDL_assert(pref == PREFER_TEXT_EVENTS_NEVER ||
-               pref == PREFER_TEXT_EVENTS_NON_ALPHA);
-
     if (mod & (KMOD_LALT | KMOD_RALT | KMOD_LGUI | KMOD_RGUI)) {
         return false;
     }

app/src/event_converter.h

@@ -2,12 +2,10 @@
 #define CONVERT_H
 
 #include <stdbool.h>
-#include <SDL2/SDL_assert.h>
 #include <SDL2/SDL_events.h>
 
 #include "config.h"
 #include "control_msg.h"
-#include "input_manager.h"
 
 bool
 convert_keycode_action(SDL_EventType from, enum android_keyevent_action *to);
@@ -17,7 +15,7 @@ convert_meta_state(SDL_Keymod mod);
 
 bool
 convert_keycode(SDL_Keycode from, enum android_keycode *to, uint16_t mod,
-                enum text_events_pref pref);
+                bool prefer_text);
 
 enum android_motionevent_buttons
 convert_mouse_buttons(uint32_t state);

app/src/input_manager.c

@@ -214,12 +214,7 @@ clipboard_paste(struct controller *controller) {
 void
 input_manager_process_text_input(struct input_manager *im,
                                  const SDL_TextInputEvent *event) {
-    if (im->text_events_pref == PREFER_TEXT_EVENTS_NEVER) {
-        // ignore all text events (key events will be injected instead)
-        return;
-    }
-
-    if (im->text_events_pref == PREFER_TEXT_EVENTS_NON_ALPHA) {
+    if (!im->prefer_text) {
         char c = event->text[0];
         if (isalpha(c) || c == ' ') {
             SDL_assert(event->text[1] == '\0');
@@ -243,7 +238,7 @@ input_manager_process_text_input(struct input_manager *im,
 
 static bool
 convert_input_key(const SDL_KeyboardEvent *from, struct control_msg *to,
-                  enum text_events_pref pref) {
+                  bool prefer_text) {
     to->type = CONTROL_MSG_TYPE_INJECT_KEYCODE;
 
     if (!convert_keycode_action(from->type, &to->inject_keycode.action)) {
@@ -252,7 +247,7 @@ convert_input_key(const SDL_KeyboardEvent *from, struct control_msg *to,
 
     uint16_t mod = from->keysym.mod;
     if (!convert_keycode(from->keysym.sym, &to->inject_keycode.keycode, mod,
-                         pref)) {
+                         prefer_text)) {
         return false;
     }
 
@@ -403,7 +398,7 @@ input_manager_process_key(struct input_manager *im,
     }
 
     struct control_msg msg;
-    if (convert_input_key(event, &msg, im->text_events_pref)) {
+    if (convert_input_key(event, &msg, im->prefer_text)) {
         if (!controller_push_msg(controller, &msg)) {
             LOGW("Could not request 'inject keycode'");
         }

app/src/input_manager.h

@@ -10,17 +10,11 @@
 #include "video_buffer.h"
 #include "screen.h"
 
-enum text_events_pref {
-    PREFER_TEXT_EVENTS_ALWAYS,
-    PREFER_TEXT_EVENTS_NON_ALPHA,
-    PREFER_TEXT_EVENTS_NEVER,
-};
-
 struct input_manager {
     struct controller *controller;
     struct video_buffer *video_buffer;
     struct screen *screen;
-    enum text_events_pref text_events_pref;
+    bool prefer_text;
 };
 
 void

app/src/main.c

@@ -11,7 +11,6 @@
 #include "config.h"
 #include "compat.h"
 #include "log.h"
-#include "input_manager.h"
 #include "recorder.h"
 
 struct args {
@@ -68,17 +67,12 @@ static void usage(const char *arg0) {
         "        Set the TCP port the client listens on.\n"
         "        Default is %d.\n"
         "\n"
-        "    --prefer-text-events mode\n"
-        "        Configure how key/text events are forwarded to the Android\n"
-        "        device.\n"
-        "        Possible values are:\n"
-        "          always:\n"
-        "            Every text is sent as text. (default)\n"
-        "          non-alpha:\n"
-        "            Only letters are sent as a sequence of key events, other\n"
-        "            characters are sent as text.\n"
-        "          never:\n"
-        "            Every text is sent as a sequence of key events.\n"
+        "    --prefer-text\n"
+        "        Inject alpha characters and space as text events instead of\n"
+        "        key events.\n"
+        "        This avoids issues when combining multiple keys to enter a\n"
+        "        special character, but breaks the expected behavior of alpha\n"
+        "        keys in games (typically WASD).\n"
         "\n"
         "    --push-target path\n"
         "        Set the target directory for pushing files to the device by\n"
@@ -307,60 +301,38 @@ guess_record_format(const char *filename) {
     return 0;
 }
 
-static bool
-parse_prefer_text_events(const char *optarg,
-                         enum text_events_pref *pref) {
-    if (!strcmp(optarg, "always")) {
-        *pref = PREFER_TEXT_EVENTS_ALWAYS;
-        return true;
-    }
-
-    if (!strcmp(optarg, "non-alpha")) {
-        *pref = PREFER_TEXT_EVENTS_NON_ALPHA;
-        return true;
-    }
-
-    if (!strcmp(optarg, "never")) {
-        *pref = PREFER_TEXT_EVENTS_NEVER;
-        return true;
-    }
-
-    LOGE("Unsupported text events preference: %s"
-         "(expected 'always', 'non-alpha' or 'never')", optarg);
-    return false;
-}
-
 #define OPT_RENDER_EXPIRED_FRAMES 1000
 #define OPT_WINDOW_TITLE          1001
 #define OPT_PUSH_TARGET           1002
-#define OPT_PREFER_TEXT_EVENTS    1003
+#define OPT_ALWAYS_ON_TOP         1003
+#define OPT_CROP                  1004
+#define OPT_RECORD_FORMAT         1005
+#define OPT_PREFER_TEXT           1006
 
 static bool
 parse_args(struct args *args, int argc, char *argv[]) {
     static const struct option long_options[] = {
-        {"always-on-top",         no_argument,       NULL, 'T'},
+        {"always-on-top",         no_argument,       NULL, OPT_ALWAYS_ON_TOP},
         {"bit-rate",              required_argument, NULL, 'b'},
-        {"crop",                  required_argument, NULL, 'c'},
+        {"crop",                  required_argument, NULL, OPT_CROP},
         {"fullscreen",            no_argument,       NULL, 'f'},
         {"help",                  no_argument,       NULL, 'h'},
         {"max-size",              required_argument, NULL, 'm'},
         {"no-control",            no_argument,       NULL, 'n'},
         {"no-display",            no_argument,       NULL, 'N'},
         {"port",                  required_argument, NULL, 'p'},
-        {"push-target",           required_argument, NULL,
-                                                 OPT_PUSH_TARGET},
+        {"push-target",           required_argument, NULL, OPT_PUSH_TARGET},
         {"record",                required_argument, NULL, 'r'},
-        {"record-format",         required_argument, NULL, 'F'},
+        {"record-format",         required_argument, NULL, OPT_RECORD_FORMAT},
         {"render-expired-frames", no_argument,       NULL,
-                                                 OPT_RENDER_EXPIRED_FRAMES},
+                                                     OPT_RENDER_EXPIRED_FRAMES},
         {"serial",                required_argument, NULL, 's'},
         {"show-touches",          no_argument,       NULL, 't'},
         {"turn-screen-off",       no_argument,       NULL, 'S'},
-        {"prefer-text-events",    required_argument, NULL,
-                                                 OPT_PREFER_TEXT_EVENTS},
+        {"prefer-text",           no_argument,       NULL, OPT_PREFER_TEXT},
         {"version",               no_argument,       NULL, 'v'},
         {"window-title",          required_argument, NULL,
-                                                 OPT_WINDOW_TITLE},
+                                                     OPT_WINDOW_TITLE},
         {NULL,                    0,                 NULL, 0  },
     };
 
@@ -376,12 +348,18 @@ parse_args(struct args *args, int argc, char *argv[]) {
                 }
                 break;
             case 'c':
+                LOGW("Deprecated option -c. Use --crop instead.");
+                // fall through
+            case OPT_CROP:
                 opts->crop = optarg;
                 break;
             case 'f':
                 opts->fullscreen = true;
                 break;
             case 'F':
+                LOGW("Deprecated option -F. Use --record-format instead.");
+                // fall through
+            case OPT_RECORD_FORMAT:
                 if (!parse_record_format(optarg, &opts->record_format)) {
                     return false;
                 }
@@ -418,6 +396,9 @@ parse_args(struct args *args, int argc, char *argv[]) {
                 opts->show_touches = true;
                 break;
             case 'T':
+                LOGW("Deprecated option -T. Use --always-on-top instead.");
+                // fall through
+            case OPT_ALWAYS_ON_TOP:
                 opts->always_on_top = true;
                 break;
             case 'v':
@@ -432,11 +413,8 @@ parse_args(struct args *args, int argc, char *argv[]) {
             case OPT_PUSH_TARGET:
                 opts->push_target = optarg;
                 break;
-            case OPT_PREFER_TEXT_EVENTS:
-                if (!parse_prefer_text_events(optarg,
-                                              &opts->text_events_pref)) {
-                    return false;
-                }
+            case OPT_PREFER_TEXT:
+                opts->prefer_text = true;
                 break;
             default:
                 // getopt prints the error message on stderr

app/src/scrcpy.c

@@ -42,7 +42,7 @@ static struct input_manager input_manager = {
     .controller = &controller,
     .video_buffer = &video_buffer,
     .screen = &screen,
-    .text_events_pref = 0, // initialized later
+    .prefer_text = false, // initialized later
 };
 
 // init SDL and set appropriate hints
@@ -415,7 +415,7 @@ scrcpy(const struct scrcpy_options *options) {
         show_touches_waited = true;
     }
 
-    input_manager.text_events_pref = options->text_events_pref;
+    input_manager.prefer_text = options->prefer_text;
 
     ret = event_loop(options->display, options->control);
     LOGD("quit...");

app/src/scrcpy.h

@@ -15,7 +15,6 @@ struct scrcpy_options {
     const char *window_title;
     const char *push_target;
     enum recorder_format record_format;
-    enum text_events_pref text_events_pref;
     uint16_t port;
     uint16_t max_size;
     uint32_t bit_rate;
@@ -26,6 +25,7 @@ struct scrcpy_options {
     bool display;
     bool turn_screen_off;
     bool render_expired_frames;
+    bool prefer_text;
 };
 
 #define SCRCPY_OPTIONS_DEFAULT { \
@@ -35,7 +35,6 @@ struct scrcpy_options {
     .window_title = NULL, \
     .push_target = NULL, \
     .record_format = RECORDER_FORMAT_AUTO, \
-    .text_events_pref = PREFER_TEXT_EVENTS_ALWAYS, \
     .port = DEFAULT_LOCAL_PORT, \
     .max_size = DEFAULT_LOCAL_PORT, \
     .bit_rate = DEFAULT_BIT_RATE, \
@@ -46,6 +45,7 @@ struct scrcpy_options {
     .display = true, \
     .turn_screen_off = false, \
     .render_expired_frames = false, \
+    .prefer_text = false, \
 }
 
 bool