Mention in README that Ctrl is forwarded

Update documentation regarding the recent copy-paste changes.

README.md

@@ -354,7 +354,7 @@ scrcpy --fullscreen
 scrcpy -f  # short version
 ```
 
-Fullscreen can then be toggled dynamically with `Ctrl`+`f`.
+Fullscreen can then be toggled dynamically with `MOD`+`f`.
 
 #### Rotation
 
@@ -370,17 +370,17 @@ Possibles values are:
  - `2`: 180 degrees
  - `3`: 90 degrees clockwise
 
-The rotation can also be changed dynamically with `Ctrl`+`←` _(left)_ and
+The rotation can also be changed dynamically with `MOD`+`←` _(left)_ and
-`Ctrl`+`→` _(right)_.
+`MOD`+`→` _(right)_.
 
 Note that _scrcpy_ manages 3 different rotations:
- - `Ctrl`+`r` requests the device to switch between portrait and landscape (the
+ - `MOD`+`r` requests the device to switch between portrait and landscape (the
    current running app may refuse, if it does support the requested
    orientation).
  - `--lock-video-orientation` changes the mirroring orientation (the orientation
    of the video sent from the device to the computer). This affects the
    recording.
- - `--rotation` (or `Ctrl`+`←`/`Ctrl`+`→`) rotates only the window content. This
+ - `--rotation` (or `MOD`+`←`/`MOD`+`→`) rotates only the window content. This
    affects only the display, not the recording.
 
 
@@ -437,9 +437,9 @@ scrcpy --turn-screen-off
 scrcpy -S
 ```
 
-Or by pressing `Ctrl`+`o` at any time.
+Or by pressing `MOD`+`o` at any time.
 
-To turn it back on, press `Ctrl`+`Shift`+`o` (or `POWER`, `Ctrl`+`p`).
+To turn it back on, press `MOD`+`Shift`+`o` (or `POWER`, `MOD`+`p`).
 
 It can be useful to also prevent the device to sleep:
 
@@ -494,24 +494,42 @@ scrcpy --disable-screensaver
 
 #### Rotate device screen
 
-Press `Ctrl`+`r` to switch between portrait and landscape modes.
+Press `MOD`+`r` to switch between portrait and landscape modes.
 
 Note that it rotates only if the application in foreground supports the
 requested orientation.
 
 #### Copy-paste
 
-It is possible to synchronize clipboards between the computer and the device, in
+Any time the Android clipboard changes, it is automatically synchronized to the
-both directions:
+computer clipboard.
 
- - `Ctrl`+`c` copies the device clipboard to the computer clipboard;
+Any `Ctrl` shortcut is forwarded to the device. In particular:
- - `Ctrl`+`Shift`+`v` copies the computer clipboard to the device clipboard (and
+ - `Ctrl`+`c` typically copies
-   pastes if the device runs Android >= 7);
+ - `Ctrl`+`x` typically cuts
- - `Ctrl`+`v` _pastes_ the computer clipboard as a sequence of text events (but
+ - `Ctrl`+`v` typically pastes (after computer-to-device clipboard
-   breaks non-ASCII characters).
+   synchronization)
 
-Moreover, any time the Android clipboard changes, it is automatically
+This typically works as you expect.
-synchronized to the computer clipboard.
+
+The actual behavior depends on the active application though. For example,
+_Termux_ sends SIGINT on `Ctrl`+`c` instead, and _K-9 Mail_ composes a new
+message.
+
+To copy, cut and paste in all cases (but only supported on Android >= 7):
+ - `MOD`+`c` injects `COPY`
+ - `MOD`+`x` injects `CUT`
+ - `MOD`+`v` injects `PASTE` (after computer-to-device clipboard
+   synchronization)
+
+In addition, `MOD`+`Shift`+`v` allows to inject the computer clipboard text as a
+sequence of key events. This is useful when the component does not accept text
+pasting (for example in _Termux_), but it can break non-ASCII content.
+
+*WARNING:* Pasting the computer clipboard to the device (either via `Ctrl`+`v`
+or `MOD`+`v`) copies the content in the device clipboard. As a consequence, any
+Android application could read its content. You should avoid to paste sensitive
+content (like passwords) that way.
 
 #### Text injection preference
 
@@ -571,33 +589,52 @@ Also see [issue #14].
 
 ## Shortcuts
 
- | Action                                      |   Shortcut                    |   Shortcut (macOS)
+In the following list, `MOD` is the shortcut modifier. By default, it's (left)
- | ------------------------------------------- |:----------------------------- |:-----------------------------
+`Alt` or (left) `Cmd`.
- | Switch fullscreen mode                      | `Ctrl`+`f`                    | `Cmd`+`f`
+
- | Rotate display left                         | `Ctrl`+`←` _(left)_           | `Cmd`+`←` _(left)_
+It can be changed using `--shortcut-mod`. Possible keys are `lctrl`, `rctrl`,
- | Rotate display right                        | `Ctrl`+`→` _(right)_          | `Cmd`+`→` _(right)_
+`lalt`, `ralt`, `lcmd` and `rcmd`. For example:
- | Resize window to 1:1 (pixel-perfect)        | `Ctrl`+`g`                    | `Cmd`+`g`
+
- | Resize window to remove black borders       | `Ctrl`+`x` \| _Double-click¹_ | `Cmd`+`x`  \| _Double-click¹_
+```bash
- | Click on `HOME`                             | `Ctrl`+`h` \| _Middle-click_  | `Ctrl`+`h` \| _Middle-click_
+# use RCtrl for shortcuts
- | Click on `BACK`                             | `Ctrl`+`b` \| _Right-click²_  | `Cmd`+`b`  \| _Right-click²_
+scrcpy --shortcut-mod=rctrl
- | Click on `APP_SWITCH`                       | `Ctrl`+`s`                    | `Cmd`+`s`
+
- | Click on `MENU`                             | `Ctrl`+`m`                    | `Ctrl`+`m`
+# use either LCtrl+LAlt or LCmd for shortcuts
- | Click on `VOLUME_UP`                        | `Ctrl`+`↑` _(up)_             | `Cmd`+`↑` _(up)_
+scrcpy --shortcut-mod=lctrl+lalt,lcmd
- | Click on `VOLUME_DOWN`                      | `Ctrl`+`↓` _(down)_           | `Cmd`+`↓` _(down)_
+```
- | Click on `POWER`                            | `Ctrl`+`p`                    | `Cmd`+`p`
+
- | Power on                                    | _Right-click²_                | _Right-click²_
+ | Action                                      |   Shortcut
- | Turn device screen off (keep mirroring)     | `Ctrl`+`o`                    | `Cmd`+`o`
+ | ------------------------------------------- |:-----------------------------
- | Turn device screen on                       | `Ctrl`+`Shift`+`o`            | `Cmd`+`Shift`+`o`
+ | Switch fullscreen mode                      | `MOD`+`f`
- | Rotate device screen                        | `Ctrl`+`r`                    | `Cmd`+`r`
+ | Rotate display left                         | `MOD`+`←` _(left)_
- | Expand notification panel                   | `Ctrl`+`n`                    | `Cmd`+`n`
+ | Rotate display right                        | `MOD`+`→` _(right)_
- | Collapse notification panel                 | `Ctrl`+`Shift`+`n`            | `Cmd`+`Shift`+`n`
+ | Resize window to 1:1 (pixel-perfect)        | `MOD`+`g`
- | Copy device clipboard to computer           | `Ctrl`+`c`                    | `Cmd`+`c`
+ | Resize window to remove black borders       | `MOD`+`w` \| _Double-click¹_
- | Paste computer clipboard to device          | `Ctrl`+`v`                    | `Cmd`+`v`
+ | Click on `HOME`                             | `MOD`+`h` \| _Middle-click_
- | Copy computer clipboard to device and paste | `Ctrl`+`Shift`+`v`            | `Cmd`+`Shift`+`v`
+ | Click on `BACK`                             | `MOD`+`b` \| _Right-click²_
- | Enable/disable FPS counter (on stdout)      | `Ctrl`+`i`                    | `Cmd`+`i`
+ | Click on `APP_SWITCH`                       | `MOD`+`s`
+ | Click on `MENU`                             | `MOD`+`m`
+ | Click on `VOLUME_UP`                        | `MOD`+`↑` _(up)_
+ | Click on `VOLUME_DOWN`                      | `MOD`+`↓` _(down)_
+ | Click on `POWER`                            | `MOD`+`p`
+ | Power on                                    | _Right-click²_
+ | Turn device screen off (keep mirroring)     | `MOD`+`o`
+ | Turn device screen on                       | `MOD`+`Shift`+`o`
+ | Rotate device screen                        | `MOD`+`r`
+ | Expand notification panel                   | `MOD`+`n`
+ | Collapse notification panel                 | `MOD`+`Shift`+`n`
+ | Copy to clipboard³                          | `MOD`+`c`
+ | Cut to clipboard³                           | `MOD`+`x`
+ | Synchronize clipboards and paste³           | `MOD`+`v`
+ | Inject computer clipboard text              | `MOD`+`Shift`+`v`
+ | Enable/disable FPS counter (on stdout)      | `MOD`+`i`
 
 _¹Double-click on black borders to remove them._  
 _²Right-click turns the screen on if it was off, presses BACK otherwise._
+_³Only on Android >= 7._
+
+All `Ctrl`+_key_ shortcuts are forwarded to the device, so they are handled by
+the active application.
 
 
 ## Custom paths

app/meson.build

@@ -186,7 +186,7 @@ if get_option('buildtype') == 'debug'
         exe = executable(t[0], t[1],
                          include_directories: src_dir,
                          dependencies: dependencies,
-                         c_args: ['-DSDL_MAIN_HANDLED'])
+                         c_args: ['-DSDL_MAIN_HANDLED', '-DSC_TEST'])
         test(t[0], exe)
     endforeach
 endif

app/scrcpy.1

@@ -149,6 +149,16 @@ Set the initial display rotation. Possibles values are 0, 1, 2 and 3. Each incre
 .BI "\-s, \-\-serial " number
 The device serial number. Mandatory only if several devices are connected to adb.
 
+.TP
+.BI "\-\-shortcut\-mod " key[+...]][,...]
+Specify the modifiers to use for scrcpy shortcuts. Possible keys are "lctrl", "rctrl", "lalt", "ralt", "lcmd" and "rcmd".
+
+A shortcut can consist in several keys, separated by '+'. Several shortcuts can be specified, separated by ','.
+
+For example, to use either LCtrl+LAlt or LCmd for scrcpy shortcuts, pass "lctrl+lalt,lcmd".
+
+Default is "lalt,lcmd" (left-Alt or left-Cmd).
+
 .TP
 .B \-S, \-\-turn\-screen\-off
 Turn the device screen off immediately.
@@ -207,52 +217,55 @@ Default is 0 (automatic).\n
 
 .SH SHORTCUTS
 
+In the following list, MOD is the shortcut modifier. By default, it's (left)
+Alt or (left) Cmd, but it can be configured by \-\-shortcut-mod.
+
 .TP
-.B Ctrl+f
+.B MOD+f
 Switch fullscreen mode
 
 .TP
-.B Ctrl+Left
+.B MOD+Left
 Rotate display left
 
 .TP
-.B Ctrl+Right
+.B MOD+Right
 Rotate display right
 
 .TP
-.B Ctrl+g
+.B MOD+g
 Resize window to 1:1 (pixel\-perfect)
 
 .TP
-.B Ctrl+x, Double\-click on black borders
+.B MOD+w, Double\-click on black borders
 Resize window to remove black borders
 
 .TP
-.B Ctrl+h, Home, Middle\-click
+.B MOD+h, Home, Middle\-click
 Click on HOME
 
 .TP
-.B Ctrl+b, Ctrl+Backspace, Right\-click (when screen is on)
+.B MOD+b, MOD+Backspace, Right\-click (when screen is on)
 Click on BACK
 
 .TP
-.B Ctrl+s
+.B MOD+s
 Click on APP_SWITCH
 
 .TP
-.B Ctrl+m
+.B MOD+m
 Click on MENU
 
 .TP
-.B Ctrl+Up
+.B MOD+Up
 Click on VOLUME_UP
 
 .TP
-.B Ctrl+Down
+.B MOD+Down
 Click on VOLUME_DOWN
 
 .TP
-.B Ctrl+p
+.B MOD+p
 Click on POWER (turn screen on/off)
 
 .TP
@@ -260,39 +273,43 @@ Click on POWER (turn screen on/off)
 Turn screen on
 
 .TP
-.B Ctrl+o
+.B MOD+o
 Turn device screen off (keep mirroring)
 
 .TP
-.B Ctrl+Shift+o
+.B MOD+Shift+o
 Turn device screen on
 
 .TP
-.B Ctrl+r
+.B MOD+r
 Rotate device screen
 
 .TP
-.B Ctrl+n
+.B MOD+n
 Expand notification panel
 
 .TP
-.B Ctrl+Shift+n
+.B MOD+Shift+n
 Collapse notification panel
 
 .TP
-.B Ctrl+c
+.B Mod+c
-Copy device clipboard to computer
+Copy to clipboard (inject COPY keycode, Android >= 7 only)
 
 .TP
-.B Ctrl+v
+.B Mod+x
-Paste computer clipboard to device
+Cut to clipboard (inject CUT keycode, Android >= 7 only)
 
 .TP
-.B Ctrl+Shift+v
+.B MOD+v
-Copy computer clipboard to device (and paste if the device runs Android >= 7)
+Copy computer clipboard to device, then paste (inject PASTE keycode, Android >= 7 only)
 
 .TP
-.B Ctrl+i
+.B MOD+Shift+v
+Inject computer clipboard text as a sequence of key events
+
+.TP
+.B MOD+i
 Enable/disable FPS counter (print frames/second in logs)
 
 .TP

app/src/cli.c

@@ -13,11 +13,6 @@
 
 void
 scrcpy_print_usage(const char *arg0) {
-#ifdef __APPLE__
-# define CTRL_OR_CMD "Cmd"
-#else
-# define CTRL_OR_CMD "Ctrl"
-#endif
     fprintf(stderr,
         "Usage: %s [options]\n"
         "\n"
@@ -143,6 +138,19 @@ scrcpy_print_usage(const char *arg0) {
         "        The device serial number. Mandatory only if several devices\n"
         "        are connected to adb.\n"
         "\n"
+        "    --shortcut-mod key[+...]][,...]\n"
+        "        Specify the modifiers to use for scrcpy shortcuts. Possible\n"
+        "        keys are \"lctrl\", \"rctrl\", \"lalt\", \"ralt\", \"lcmd\"\n"
+        "        and \"rcmd\".\n"
+        "\n"
+        "        A shortcut can consist in several keys, separated by '+'.\n"
+        "        Several shortcuts can be specified, separated by ','.\n"
+        "\n"
+        "        For example, to use either LCtrl+LAlt or LCmd for scrcpy\n"
+        "        shortcuts, pass \"lctrl+lalt,lcmd\".\n"
+        "\n"
+        "        Default is \"lalt,lcmd\" (left-Alt or left-Cmd).\n"
+        "\n"
         "    -S, --turn-screen-off\n"
         "        Turn the device screen off immediately.\n"
         "\n"
@@ -190,75 +198,82 @@ scrcpy_print_usage(const char *arg0) {
         "\n"
         "Shortcuts:\n"
         "\n"
-        "    " CTRL_OR_CMD "+f\n"
+        "    In the following list, MOD is the shortcut modifier. By default,\n"
+        "    it's (left) Alt or (left) Cmd, but it can be configured by\n"
+        "    --shortcut-mod.\n"
+        "\n"
+        "    MOD+f\n"
         "        Switch fullscreen mode\n"
         "\n"
-        "    " CTRL_OR_CMD "+Left\n"
+        "    MOD+Left\n"
         "        Rotate display left\n"
         "\n"
-        "    " CTRL_OR_CMD "+Right\n"
+        "    MOD+Right\n"
         "        Rotate display right\n"
         "\n"
-        "    " CTRL_OR_CMD "+g\n"
+        "    MOD+g\n"
         "        Resize window to 1:1 (pixel-perfect)\n"
         "\n"
-        "    " CTRL_OR_CMD "+x\n"
+        "    MOD+w\n"
         "    Double-click on black borders\n"
         "        Resize window to remove black borders\n"
         "\n"
-        "    Ctrl+h\n"
+        "    MOD+h\n"
         "    Middle-click\n"
         "        Click on HOME\n"
         "\n"
-        "    " CTRL_OR_CMD "+b\n"
+        "    MOD+b\n"
-        "    " CTRL_OR_CMD "+Backspace\n"
+        "    MOD+Backspace\n"
         "    Right-click (when screen is on)\n"
         "        Click on BACK\n"
         "\n"
-        "    " CTRL_OR_CMD "+s\n"
+        "    MOD+s\n"
         "        Click on APP_SWITCH\n"
         "\n"
-        "    Ctrl+m\n"
+        "    MOD+m\n"
         "        Click on MENU\n"
         "\n"
-        "    " CTRL_OR_CMD "+Up\n"
+        "    MOD+Up\n"
         "        Click on VOLUME_UP\n"
         "\n"
-        "    " CTRL_OR_CMD "+Down\n"
+        "    MOD+Down\n"
         "        Click on VOLUME_DOWN\n"
         "\n"
-        "    " CTRL_OR_CMD "+p\n"
+        "    MOD+p\n"
         "        Click on POWER (turn screen on/off)\n"
         "\n"
         "    Right-click (when screen is off)\n"
         "        Power on\n"
         "\n"
-        "    " CTRL_OR_CMD "+o\n"
+        "    MOD+o\n"
         "        Turn device screen off (keep mirroring)\n"
         "\n"
-        "    " CTRL_OR_CMD "+Shift+o\n"
+        "    MOD+Shift+o\n"
         "        Turn device screen on\n"
         "\n"
-        "    " CTRL_OR_CMD "+r\n"
+        "    MOD+r\n"
         "        Rotate device screen\n"
         "\n"
-        "    " CTRL_OR_CMD "+n\n"
+        "    MOD+n\n"
         "        Expand notification panel\n"
         "\n"
-        "    " CTRL_OR_CMD "+Shift+n\n"
+        "    MOD+Shift+n\n"
         "        Collapse notification panel\n"
         "\n"
-        "    " CTRL_OR_CMD "+c\n"
+        "    MOD+c\n"
-        "        Copy device clipboard to computer\n"
+        "        Copy to clipboard (inject COPY keycode, Android >= 7 only)\n"
         "\n"
-        "    " CTRL_OR_CMD "+v\n"
+        "    MOD+x\n"
-        "        Paste computer clipboard to device\n"
+        "        Cut to clipboard (inject CUT keycode, Android >= 7 only)\n"
         "\n"
-        "    " CTRL_OR_CMD "+Shift+v\n"
+        "    MOD+v\n"
-        "        Copy computer clipboard to device (and paste if the device\n"
+        "        Copy computer clipboard to device, then paste (inject PASTE\n"
-        "        runs Android >= 7)\n"
+        "        keycode, Android >= 7 only)\n"
         "\n"
-        "    " CTRL_OR_CMD "+i\n"
+        "    MOD+Shift+v\n"
+        "        Inject computer clipboard text as a sequence of key events\n"
+        "\n"
+        "    MOD+i\n"
         "        Enable/disable FPS counter (print frames/second in logs)\n"
         "\n"
         "    Drag & drop APK file\n"
@@ -480,6 +495,101 @@ parse_log_level(const char *s, enum sc_log_level *log_level) {
     return false;
 }
 
+// item is a list of mod keys separated by '+' (e.g. "lctrl+lalt")
+// returns a bitwise-or of SC_MOD_* constants (or 0 on error)
+static unsigned
+parse_shortcut_mods_item(const char *item, size_t len) {
+    unsigned mod = 0;
+
+    for (;;) {
+        char *plus = strchr(item, '+');
+        // strchr() does not consider the "len" parameter, to it could find an
+        // occurrence too far in the string (there is no strnchr())
+        bool has_plus = plus && plus < item + len;
+
+        assert(!has_plus || plus > item);
+        size_t key_len = has_plus ? (size_t) (plus - item) : len;
+
+#define STREQ(literal, s, len) \
+    ((sizeof(literal)-1 == len) && !memcmp(literal, s, len))
+
+        if (STREQ("lctrl", item, key_len)) {
+            mod |= SC_MOD_LCTRL;
+        } else if (STREQ("rctrl", item, key_len)) {
+            mod |= SC_MOD_RCTRL;
+        } else if (STREQ("lalt", item, key_len)) {
+            mod |= SC_MOD_LALT;
+        } else if (STREQ("ralt", item, key_len)) {
+            mod |= SC_MOD_RALT;
+        } else if (STREQ("lcmd", item, key_len)) {
+            mod |= SC_MOD_LCMD;
+        } else if (STREQ("rcmd", item, key_len)) {
+            mod |= SC_MOD_RCMD;
+        } else {
+            LOGW("Unknown modifier key: %.*s", (int) key_len, item);
+            return 0;
+        }
+#undef STREQ
+
+        if (!has_plus) {
+            break;
+        }
+
+        item = plus + 1;
+        assert(len >= key_len + 1);
+        len -= key_len + 1;
+    }
+
+    return mod;
+}
+
+static bool
+parse_shortcut_mods(const char *s, struct sc_shortcut_mods *mods) {
+    unsigned count = 0;
+    unsigned current = 0;
+
+    // LCtrl+LAlt or RCtrl or LCtrl+RCmd: "lctrl+lalt,rctrl,lctrl+rcmd"
+
+    for (;;) {
+        char *comma = strchr(s, ',');
+        if (comma && count == SC_MAX_SHORTCUT_MODS - 1) {
+            assert(count < SC_MAX_SHORTCUT_MODS);
+            LOGW("Too many shortcut modifiers alternatives");
+            return false;
+        }
+
+        assert(!comma || comma > s);
+        size_t limit = comma ? (size_t) (comma - s) : strlen(s);
+
+        unsigned mod = parse_shortcut_mods_item(s, limit);
+        if (!mod) {
+            LOGE("Invalid modifier keys: %.*s", (int) limit, s);
+            return false;
+        }
+
+        mods->data[current++] = mod;
+        ++count;
+
+        if (!comma) {
+            break;
+        }
+
+        s = comma + 1;
+    }
+
+    mods->count = count;
+
+    return true;
+}
+
+#ifdef SC_TEST
+// expose the function to unit-tests
+bool
+sc_parse_shortcut_mods(const char *s, struct sc_shortcut_mods *mods) {
+    return parse_shortcut_mods(s, mods);
+}
+#endif
+
 static bool
 parse_record_format(const char *optarg, enum sc_record_format *format) {
     if (!strcmp(optarg, "mp4")) {
@@ -531,6 +641,7 @@ guess_record_format(const char *filename) {
 #define OPT_CODEC_OPTIONS          1018
 #define OPT_FORCE_ADB_FORWARD      1019
 #define OPT_DISABLE_SCREENSAVER    1020
+#define OPT_SHORTCUT_MOD           1021
 
 bool
 scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
@@ -563,6 +674,7 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
                                                   OPT_RENDER_EXPIRED_FRAMES},
         {"rotation",               required_argument, NULL, OPT_ROTATION},
         {"serial",                 required_argument, NULL, 's'},
+        {"shortcut-mod",           required_argument, NULL, OPT_SHORTCUT_MOD},
         {"show-touches",           no_argument,       NULL, 't'},
         {"stay-awake",             no_argument,       NULL, 'w'},
         {"turn-screen-off",        no_argument,       NULL, 'S'},
@@ -726,6 +838,11 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
             case OPT_DISABLE_SCREENSAVER:
                 opts->disable_screensaver = true;
                 break;
+            case OPT_SHORTCUT_MOD:
+                if (!parse_shortcut_mods(optarg, &opts->shortcut_mods)) {
+                    return false;
+                }
+                break;
             default:
                 // getopt prints the error message on stderr
                 return false;

app/src/cli.h

@@ -18,4 +18,9 @@ scrcpy_print_usage(const char *arg0);
 bool
 scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]);
 
+#ifdef SC_TEST
+bool
+sc_parse_shortcut_mods(const char *s, struct sc_shortcut_mods *mods);
+#endif
+
 #endif

app/src/event_converter.c

@@ -92,6 +92,10 @@ convert_keycode(SDL_Keycode from, enum android_keycode *to, uint16_t mod,
         MAP(SDLK_LEFT,         AKEYCODE_DPAD_LEFT);
         MAP(SDLK_DOWN,         AKEYCODE_DPAD_DOWN);
         MAP(SDLK_UP,           AKEYCODE_DPAD_UP);
+        MAP(SDLK_LCTRL,        AKEYCODE_CTRL_LEFT);
+        MAP(SDLK_RCTRL,        AKEYCODE_CTRL_RIGHT);
+        MAP(SDLK_LSHIFT,       AKEYCODE_SHIFT_LEFT);
+        MAP(SDLK_RSHIFT,       AKEYCODE_SHIFT_RIGHT);
     }
 
     if (!(mod & (KMOD_NUM | KMOD_SHIFT))) {
@@ -111,8 +115,8 @@ convert_keycode(SDL_Keycode from, enum android_keycode *to, uint16_t mod,
         }
     }
 
-    if (prefer_text) {
+    if (prefer_text && !(mod & KMOD_CTRL)) {
-        // do not forward alpha and space key events
+        // do not forward alpha and space key events (unless Ctrl is pressed)
         return false;
     }
 

app/src/input_manager.c

@@ -1,6 +1,7 @@
 #include "input_manager.h"
 
 #include <assert.h>
+#include <SDL2/SDL_keycode.h>
 
 #include "config.h"
 #include "event_converter.h"
@@ -10,6 +11,64 @@
 static const int ACTION_DOWN = 1;
 static const int ACTION_UP = 1 << 1;
 
+#define SC_SDL_SHORTCUT_MODS_MASK (KMOD_CTRL | KMOD_ALT | KMOD_GUI)
+
+static inline uint16_t
+to_sdl_mod(unsigned mod) {
+    uint16_t sdl_mod = 0;
+    if (mod & SC_MOD_LCTRL) {
+        sdl_mod |= KMOD_LCTRL;
+    }
+    if (mod & SC_MOD_RCTRL) {
+        sdl_mod |= KMOD_RCTRL;
+    }
+    if (mod & SC_MOD_LALT) {
+        sdl_mod |= KMOD_LALT;
+    }
+    if (mod & SC_MOD_RALT) {
+        sdl_mod |= KMOD_RALT;
+    }
+    if (mod & SC_MOD_LCMD) {
+        sdl_mod |= KMOD_LGUI;
+    }
+    if (mod & SC_MOD_RCMD) {
+        sdl_mod |= KMOD_RGUI;
+    }
+    return sdl_mod;
+}
+
+static bool
+is_shortcut_mod(struct input_manager *im, uint16_t sdl_mod) {
+    // keep only the relevant modifier keys
+    sdl_mod &= SC_SDL_SHORTCUT_MODS_MASK;
+
+    assert(im->sdl_shortcut_mods.count);
+    assert(im->sdl_shortcut_mods.count < SC_MAX_SHORTCUT_MODS);
+    for (unsigned i = 0; i < im->sdl_shortcut_mods.count; ++i) {
+        if (im->sdl_shortcut_mods.data[i] == sdl_mod) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+void
+input_manager_init(struct input_manager *im, bool prefer_text,
+                   const struct sc_shortcut_mods *shortcut_mods)
+{
+    im->prefer_text = prefer_text;
+
+    assert(shortcut_mods->count);
+    assert(shortcut_mods->count < SC_MAX_SHORTCUT_MODS);
+    for (unsigned i = 0; i < shortcut_mods->count; ++i) {
+        uint16_t sdl_mod = to_sdl_mod(shortcut_mods->data[i]);
+        assert(sdl_mod);
+        im->sdl_shortcut_mods.data[i] = sdl_mod;
+    }
+    im->sdl_shortcut_mods.count = shortcut_mods->count;
+}
+
 static void
 send_keycode(struct controller *controller, enum android_keycode keycode,
              int actions, const char *name) {
@@ -70,6 +129,16 @@ action_menu(struct controller *controller, int actions) {
     send_keycode(controller, AKEYCODE_MENU, actions, "MENU");
 }
 
+static inline void
+action_copy(struct controller *controller, int actions) {
+    send_keycode(controller, AKEYCODE_COPY, actions, "COPY");
+}
+
+static inline void
+action_cut(struct controller *controller, int actions) {
+    send_keycode(controller, AKEYCODE_CUT, actions, "CUT");
+}
+
 // turn the screen on if it was off, press BACK otherwise
 static void
 press_back_or_turn_screen_on(struct controller *controller) {
@@ -101,16 +170,6 @@ collapse_notification_panel(struct controller *controller) {
     }
 }
 
-static void
-request_device_clipboard(struct controller *controller) {
-    struct control_msg msg;
-    msg.type = CONTROL_MSG_TYPE_GET_CLIPBOARD;
-
-    if (!controller_push_msg(controller, &msg)) {
-        LOGW("Could not request device clipboard");
-    }
-}
-
 static void
 set_device_clipboard(struct controller *controller, bool paste) {
     char *text = SDL_GetClipboardText();
@@ -210,6 +269,10 @@ rotate_client_right(struct screen *screen) {
 void
 input_manager_process_text_input(struct input_manager *im,
                                  const SDL_TextInputEvent *event) {
+    if (is_shortcut_mod(im, SDL_GetModState())) {
+        // A shortcut must never generate text events
+        return;
+    }
     if (!im->prefer_text) {
         char c = event->text[0];
         if (isalpha(c) || c == ' ') {
@@ -258,71 +321,49 @@ input_manager_process_key(struct input_manager *im,
                           const SDL_KeyboardEvent *event,
                           bool control) {
     // control: indicates the state of the command-line option --no-control
-    // ctrl: the Ctrl key
 
-    bool ctrl = event->keysym.mod & (KMOD_LCTRL | KMOD_RCTRL);
+    bool smod = is_shortcut_mod(im, event->keysym.mod);
-    bool alt = event->keysym.mod & (KMOD_LALT | KMOD_RALT);
-    bool meta = event->keysym.mod & (KMOD_LGUI | KMOD_RGUI);
-
-    // use Cmd on macOS, Ctrl on other platforms
-#ifdef __APPLE__
-    bool cmd = !ctrl && meta;
-#else
-    if (meta) {
-        // no shortcuts involve Meta on platforms other than macOS, and it must
-        // not be forwarded to the device
-        return;
-    }
-    bool cmd = ctrl; // && !meta, already guaranteed
-#endif
-
-    if (alt) {
-        // no shortcuts involve Alt, and it must not be forwarded to the device
-        return;
-    }
 
     struct controller *controller = im->controller;
 
-    // capture all Ctrl events
+    SDL_Keycode keycode = event->keysym.sym;
-    if (ctrl || cmd) {
+    bool down = event->type == SDL_KEYDOWN;
-        SDL_Keycode keycode = event->keysym.sym;
+    bool ctrl = event->keysym.mod & KMOD_CTRL;
-        bool down = event->type == SDL_KEYDOWN;
+    bool shift = event->keysym.mod & KMOD_SHIFT;
+    bool repeat = event->repeat;
+
+    // The shortcut modifier is pressed
+    if (smod) {
         int action = down ? ACTION_DOWN : ACTION_UP;
-        bool repeat = event->repeat;
-        bool shift = event->keysym.mod & (KMOD_LSHIFT | KMOD_RSHIFT);
         switch (keycode) {
             case SDLK_h:
-                // Ctrl+h on all platform, since Cmd+h is already captured by
+                if (control && !shift && !repeat) {
-                // the system on macOS to hide the window
-                if (control && ctrl && !meta && !shift && !repeat) {
                     action_home(controller, action);
                 }
                 return;
             case SDLK_b: // fall-through
             case SDLK_BACKSPACE:
-                if (control && cmd && !shift && !repeat) {
+                if (control && !shift && !repeat) {
                     action_back(controller, action);
                 }
                 return;
             case SDLK_s:
-                if (control && cmd && !shift && !repeat) {
+                if (control && !shift && !repeat) {
                     action_app_switch(controller, action);
                 }
                 return;
             case SDLK_m:
-                // Ctrl+m on all platform, since Cmd+m is already captured by
+                if (control && !shift && !repeat) {
-                // the system on macOS to minimize the window
-                if (control && ctrl && !meta && !shift && !repeat) {
                     action_menu(controller, action);
                 }
                 return;
             case SDLK_p:
-                if (control && cmd && !shift && !repeat) {
+                if (control && !shift && !repeat) {
                     action_power(controller, action);
                 }
                 return;
             case SDLK_o:
-                if (control && cmd && !repeat && down) {
+                if (control && !repeat && down) {
                     enum screen_power_mode mode = shift
                                                 ? SCREEN_POWER_MODE_NORMAL
                                                 : SCREEN_POWER_MODE_OFF;
@@ -330,67 +371,72 @@ input_manager_process_key(struct input_manager *im,
                 }
                 return;
             case SDLK_DOWN:
-                if (control && cmd && !shift) {
+                if (control && !shift) {
                     // forward repeated events
                     action_volume_down(controller, action);
                 }
                 return;
             case SDLK_UP:
-                if (control && cmd && !shift) {
+                if (control && !shift) {
                     // forward repeated events
                     action_volume_up(controller, action);
                 }
                 return;
             case SDLK_LEFT:
-                if (cmd && !shift && !repeat && down) {
+                if (!shift && !repeat && down) {
                     rotate_client_left(im->screen);
                 }
                 return;
             case SDLK_RIGHT:
-                if (cmd && !shift && !repeat && down) {
+                if (!shift && !repeat && down) {
                     rotate_client_right(im->screen);
                 }
                 return;
             case SDLK_c:
-                if (control && cmd && !shift && !repeat && down) {
+                if (control && !shift && !repeat) {
-                    request_device_clipboard(controller);
+                    action_copy(controller, action);
+                }
+                return;
+            case SDLK_x:
+                if (control && !shift && !repeat) {
+                    action_cut(controller, action);
                 }
                 return;
             case SDLK_v:
-                if (control && cmd && !repeat && down) {
+                if (control && !repeat && down) {
                     if (shift) {
-                        // store the text in the device clipboard and paste
-                        set_device_clipboard(controller, true);
-                    } else {
                         // inject the text as input events
                         clipboard_paste(controller);
+                    } else {
+                        // store the text in the device clipboard and paste
+                        set_device_clipboard(controller, true);
                     }
                 }
                 return;
             case SDLK_f:
-                if (cmd && !shift && !repeat && down) {
+                if (!shift && !repeat && down) {
                     screen_switch_fullscreen(im->screen);
                 }
                 return;
-            case SDLK_x:
+            case SDLK_w:
-                if (cmd && !shift && !repeat && down) {
+                if (!shift && !repeat && down) {
                     screen_resize_to_fit(im->screen);
                 }
                 return;
             case SDLK_g:
-                if (cmd && !shift && !repeat && down) {
+                if (!shift && !repeat && down) {
                     screen_resize_to_pixel_perfect(im->screen);
                 }
                 return;
             case SDLK_i:
-                if (cmd && !shift && !repeat && down) {
+                if (!shift && !repeat && down) {
                     struct fps_counter *fps_counter =
                         im->video_buffer->fps_counter;
                     switch_fps_counter_state(fps_counter);
                 }
                 return;
             case SDLK_n:
-                if (control && cmd && !repeat && down) {
+                if (control && !repeat && down) {
                     if (shift) {
                         collapse_notification_panel(controller);
                     } else {
@@ -399,7 +445,7 @@ input_manager_process_key(struct input_manager *im,
                 }
                 return;
             case SDLK_r:
-                if (control && cmd && !shift && !repeat && down) {
+                if (control && !shift && !repeat && down) {
                     rotate_device(controller);
                 }
                 return;
@@ -418,6 +464,12 @@ input_manager_process_key(struct input_manager *im,
         im->repeat = 0;
     }
 
+    if (ctrl && !shift && keycode == SDLK_v && down && !repeat) {
+        // Synchronize the computer clipboard to the device clipboard before
+        // sending Ctrl+v, to allow seamless copy-paste.
+        set_device_clipboard(controller, false);
+    }
+
     struct control_msg msg;
     if (convert_input_key(event, &msg, im->prefer_text, im->repeat)) {
         if (!controller_push_msg(controller, &msg)) {

app/src/input_manager.h

@@ -3,12 +3,15 @@
 
 #include <stdbool.h>
 
+#include <SDL2/SDL.h>
+
 #include "config.h"
 #include "common.h"
 #include "controller.h"
 #include "fps_counter.h"
-#include "video_buffer.h"
+#include "scrcpy.h"
 #include "screen.h"
+#include "video_buffer.h"
 
 struct input_manager {
     struct controller *controller;
@@ -20,8 +23,17 @@ struct input_manager {
     unsigned repeat;
 
     bool prefer_text;
+
+    struct {
+        unsigned data[SC_MAX_SHORTCUT_MODS];
+        unsigned count;
+    } sdl_shortcut_mods;
 };
 
+void
+input_manager_init(struct input_manager *im, bool prefer_text,
+                   const struct sc_shortcut_mods *shortcut_mods);
+
 void
 input_manager_process_text_input(struct input_manager *im,
                                  const SDL_TextInputEvent *event);

app/src/receiver.c

@@ -25,10 +25,19 @@ receiver_destroy(struct receiver *receiver) {
 static void
 process_msg(struct device_msg *msg) {
     switch (msg->type) {
-        case DEVICE_MSG_TYPE_CLIPBOARD:
+        case DEVICE_MSG_TYPE_CLIPBOARD: {
+            char *current = SDL_GetClipboardText();
+            bool same = current && !strcmp(current, msg->clipboard.text);
+            SDL_free(current);
+            if (same) {
+                LOGD("Computer clipboard unchanged");
+                return;
+            }
+
             LOGI("Device clipboard copied");
             SDL_SetClipboardText(msg->clipboard.text);
             break;
+        }
     }
 }
 

app/src/scrcpy.c

@@ -49,7 +49,13 @@ static struct input_manager input_manager = {
     .video_buffer = &video_buffer,
     .screen = &screen,
     .repeat = 0,
-    .prefer_text = false, // initialized later
+
+    // initialized later
+    .prefer_text = false,
+    .sdl_shortcut_mods = {
+        .data = {0},
+        .count = 0,
+    },
 };
 
 #ifdef _WIN32
@@ -437,7 +443,8 @@ scrcpy(const struct scrcpy_options *options) {
         }
     }
 
-    input_manager.prefer_text = options->prefer_text;
+    input_manager_init(&input_manager, options->prefer_text,
+                       &options->shortcut_mods);
 
     ret = event_loop(options->display, options->control);
     LOGD("quit...");

app/src/scrcpy.h

@@ -20,6 +20,22 @@ enum sc_record_format {
     SC_RECORD_FORMAT_MKV,
 };
 
+#define SC_MAX_SHORTCUT_MODS 8
+
+enum sc_shortcut_mod {
+    SC_MOD_LCTRL = 1 << 0,
+    SC_MOD_RCTRL = 1 << 1,
+    SC_MOD_LALT = 1 << 2,
+    SC_MOD_RALT = 1 << 3,
+    SC_MOD_LCMD = 1 << 4,
+    SC_MOD_RCMD = 1 << 5,
+};
+
+struct sc_shortcut_mods {
+    unsigned data[SC_MAX_SHORTCUT_MODS];
+    unsigned count;
+};
+
 struct sc_port_range {
     uint16_t first;
     uint16_t last;
@@ -38,6 +54,7 @@ struct scrcpy_options {
     enum sc_log_level log_level;
     enum sc_record_format record_format;
     struct sc_port_range port_range;
+    struct sc_shortcut_mods shortcut_mods;
     uint16_t max_size;
     uint32_t bit_rate;
     uint16_t max_fps;
@@ -77,6 +94,10 @@ struct scrcpy_options {
         .first = DEFAULT_LOCAL_PORT_RANGE_FIRST, \
         .last = DEFAULT_LOCAL_PORT_RANGE_LAST, \
     }, \
+    .shortcut_mods = { \
+        .data = {SC_MOD_LALT, SC_MOD_LCMD}, \
+        .count = 2, \
+    }, \
     .max_size = DEFAULT_MAX_SIZE, \
     .bit_rate = DEFAULT_BIT_RATE, \
     .max_fps = 0, \

app/tests/test_cli.c

@@ -3,6 +3,7 @@
 
 #include "cli.h"
 #include "common.h"
+#include "scrcpy.h"
 
 static void test_flag_version(void) {
     struct scrcpy_cli_args args = {
@@ -122,6 +123,43 @@ static void test_options2(void) {
     assert(opts->record_format == SC_RECORD_FORMAT_MP4);
 }
 
+static void test_parse_shortcut_mods(void) {
+    struct sc_shortcut_mods mods;
+    bool ok;
+
+    ok = sc_parse_shortcut_mods("lctrl", &mods);
+    assert(ok);
+    assert(mods.count == 1);
+    assert(mods.data[0] == SC_MOD_LCTRL);
+
+    ok = sc_parse_shortcut_mods("lctrl+lalt", &mods);
+    assert(ok);
+    assert(mods.count == 1);
+    assert(mods.data[0] == (SC_MOD_LCTRL | SC_MOD_LALT));
+
+    ok = sc_parse_shortcut_mods("rctrl,lalt", &mods);
+    assert(ok);
+    assert(mods.count == 2);
+    assert(mods.data[0] == SC_MOD_RCTRL);
+    assert(mods.data[1] == SC_MOD_LALT);
+
+    ok = sc_parse_shortcut_mods("lcmd,rcmd+lalt,lctrl+rctrl+ralt", &mods);
+    assert(ok);
+    assert(mods.count == 3);
+    assert(mods.data[0] == SC_MOD_LCMD);
+    assert(mods.data[1] == (SC_MOD_RCMD | SC_MOD_LALT));
+    assert(mods.data[2] == (SC_MOD_LCTRL | SC_MOD_RCTRL | SC_MOD_RALT));
+
+    ok = sc_parse_shortcut_mods("", &mods);
+    assert(!ok);
+
+    ok = sc_parse_shortcut_mods("lctrl+", &mods);
+    assert(!ok);
+
+    ok = sc_parse_shortcut_mods("lctrl,", &mods);
+    assert(!ok);
+}
+
 int main(int argc, char *argv[]) {
     (void) argc;
     (void) argv;
@@ -130,5 +168,6 @@ int main(int argc, char *argv[]) {
     test_flag_help();
     test_options();
     test_options2();
+    test_parse_shortcut_mods();
     return 0;
 };

server/src/main/java/com/genymobile/scrcpy/Device.java

@@ -221,6 +221,16 @@ public final class Device {
         if (clipboardManager == null) {
             return false;
         }
+
+        String currentClipboard = getClipboardText();
+        if (currentClipboard == null || currentClipboard.equals(text)) {
+            // The clipboard already contains the requested text.
+            // Since pasting text from the computer involves setting the device clipboard, it could be set twice on a copy-paste. This would cause
+            // the clipboard listeners to be notified twice, and that would flood the Android keyboard clipboard history. To workaround this
+            // problem, do not explicitly set the clipboard text if it already contains the expected content.
+            return false;
+        }
+
         isSettingClipboard.set(true);
         boolean ok = clipboardManager.setText(text);
         isSettingClipboard.set(false);