From d14a12638309a3cba55bbb245df3347379b86f8f Mon Sep 17 00:00:00 2001
From: Zach Reedy <[EMAIL REDACTED]>
Date: Fri, 11 Mar 2022 17:45:17 -0500
Subject: [PATCH] IME Composition Truncation + SDL_IsTextInputShown +
SDL_ClearComposition (#5398)
* Fixes for IME Composition Truncation + Addition of SDL_ClearComposition, SDL_IsTextInputShown
* Fixed: Documentation and code style issues raised during code review.
---
include/SDL_events.h | 15 +++
include/SDL_hints.h | 11 ++
include/SDL_keyboard.h | 18 ++++
src/dynapi/SDL_dynapi_overrides.h | 2 +
src/dynapi/SDL_dynapi_procs.h | 2 +
src/events/SDL_keyboard.c | 16 +++
src/video/SDL_sysvideo.h | 2 +
src/video/SDL_video.c | 18 ++++
src/video/windows/SDL_windowskeyboard.c | 129 ++++++++++++++++++++++--
src/video/windows/SDL_windowskeyboard.h | 2 +
src/video/windows/SDL_windowsvideo.c | 2 +
src/video/windows/SDL_windowsvideo.h | 5 +-
12 files changed, 210 insertions(+), 12 deletions(-)
diff --git a/include/SDL_events.h b/include/SDL_events.h
index 3722a6311a8..7e469070ecd 100644
--- a/include/SDL_events.h
+++ b/include/SDL_events.h
@@ -102,6 +102,7 @@ typedef enum
SDL_KEYMAPCHANGED, /**< Keymap changed due to a system event such as an
input language or keyboard layout change.
*/
+ SDL_TEXTEDITING_EXT, /**< Extended keyboard text editing (composition) */
/* Mouse events */
SDL_MOUSEMOTION = 0x400, /**< Mouse moved */
@@ -243,6 +244,19 @@ typedef struct SDL_TextEditingEvent
Sint32 length; /**< The length of selected editing text */
} SDL_TextEditingEvent;
+/**
+ * \brief Extended keyboard text editing event structure (event.editExt.*) when text would be
+ * truncated if stored in the text buffer SDL_TextEditingEvent
+ */
+typedef struct SDL_TextEditingExtEvent
+{
+ Uint32 type; /**< ::SDL_TEXTEDITING_EXT */
+ Uint32 timestamp; /**< In milliseconds, populated using SDL_GetTicks() */
+ Uint32 windowID; /**< The window with keyboard focus, if any */
+ char* text; /**< The editing text, which should be freed with SDL_free(), and will not be NULL */
+ Sint32 start; /**< The start cursor of selected editing text */
+ Sint32 length; /**< The length of selected editing text */
+} SDL_TextEditingExtEvent;
#define SDL_TEXTINPUTEVENT_TEXT_SIZE (32)
/**
@@ -601,6 +615,7 @@ typedef union SDL_Event
SDL_WindowEvent window; /**< Window event data */
SDL_KeyboardEvent key; /**< Keyboard event data */
SDL_TextEditingEvent edit; /**< Text editing event data */
+ SDL_TextEditingExtEvent editExt; /**< Extended text editing event data */
SDL_TextInputEvent text; /**< Text input event data */
SDL_MouseMotionEvent motion; /**< Mouse motion event data */
SDL_MouseButtonEvent button; /**< Mouse button event data */
diff --git a/include/SDL_hints.h b/include/SDL_hints.h
index 92fbb5778b2..384320e0665 100644
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -579,6 +579,17 @@ extern "C" {
*/
#define SDL_HINT_IME_SHOW_UI "SDL_IME_SHOW_UI"
+/**
+ * \brief A variable to control if extended IME text support is enabled.
+ * If enabled then SDL_TextEditingExtEvent will be issued if the text would be truncated otherwise.
+ * Additionally SDL_TextInputEvent will be dispatched multiple times so that it is not truncated.
+ *
+ * The variable can be set to the following values:
+ * "0" - Legacy behavior. Text can be truncated, no heap allocations. (default)
+ * "1" - Modern behavior.
+ */
+#define SDL_HINT_IME_SUPPORT_EXTENDED_TEXT "SDL_IME_SUPPORT_EXTENDED_TEXT"
+
/**
* \brief A variable controlling whether the home indicator bar on iPhone X
* should be hidden.
diff --git a/include/SDL_keyboard.h b/include/SDL_keyboard.h
index 86824655c8c..5489cb9df08 100644
--- a/include/SDL_keyboard.h
+++ b/include/SDL_keyboard.h
@@ -268,6 +268,24 @@ extern DECLSPEC SDL_bool SDLCALL SDL_IsTextInputActive(void);
*/
extern DECLSPEC void SDLCALL SDL_StopTextInput(void);
+/**
+ * Dismiss the composition window/IME without disabling the subsystem.
+ *
+ * \since This function is available since SDL 2.0.22
+ *
+ * \sa SDL_StartTextInput
+ * \sa SDL_StopTextInput
+ */
+extern DECLSPEC void SDLCALL SDL_ClearComposition(void);
+
+/**
+ * Returns if an IME Composite or Candidate window is currently shown.
+ *
+ * \since This function is available since SDL 2.0.22
+ *
+ */
+extern DECLSPEC SDL_bool SDLCALL SDL_IsTextInputShown(void);
+
/**
* Set the rectangle used to type Unicode text inputs.
*
diff --git a/src/dynapi/SDL_dynapi_overrides.h b/src/dynapi/SDL_dynapi_overrides.h
index 2573a042257..6e652e45a56 100644
--- a/src/dynapi/SDL_dynapi_overrides.h
+++ b/src/dynapi/SDL_dynapi_overrides.h
@@ -857,3 +857,5 @@
#define SDL_PremultiplyAlpha SDL_PremultiplyAlpha_REAL
#define SDL_AndroidSendMessage SDL_AndroidSendMessage_REAL
#define SDL_GetTouchName SDL_GetTouchName_REAL
+#define SDL_ClearComposition SDL_ClearComposition_REAL
+#define SDL_IsTextInputShown SDL_IsTextInputShown_REAL
diff --git a/src/dynapi/SDL_dynapi_procs.h b/src/dynapi/SDL_dynapi_procs.h
index b1ea912cd5c..6323185767b 100644
--- a/src/dynapi/SDL_dynapi_procs.h
+++ b/src/dynapi/SDL_dynapi_procs.h
@@ -928,3 +928,5 @@ SDL_DYNAPI_PROC(int,SDL_PremultiplyAlpha,(int a, int b, Uint32 c, const void *d,
SDL_DYNAPI_PROC(int,SDL_AndroidSendMessage,(Uint32 a, int b),(a,b),return)
#endif
SDL_DYNAPI_PROC(const char*,SDL_GetTouchName,(int a),(a),return)
+SDL_DYNAPI_PROC(void,SDL_ClearComposition,(void),(),)
+SDL_DYNAPI_PROC(SDL_bool,SDL_IsTextInputShown,(void),(),return)
diff --git a/src/events/SDL_keyboard.c b/src/events/SDL_keyboard.c
index bc2386b44c0..cd150fab699 100644
--- a/src/events/SDL_keyboard.c
+++ b/src/events/SDL_keyboard.c
@@ -894,6 +894,22 @@ SDL_SendEditingText(const char *text, int start, int length)
event.edit.start = start;
event.edit.length = length;
SDL_utf8strlcpy(event.edit.text, text, SDL_arraysize(event.edit.text));
+
+ if (SDL_GetHintBoolean(SDL_HINT_IME_SUPPORT_EXTENDED_TEXT, SDL_FALSE) &&
+ SDL_strlen(text) > SDL_arraysize(event.text.text)) {
+ event.editExt.type = SDL_TEXTEDITING_EXT;
+ event.editExt.windowID = keyboard->focus ? keyboard->focus->id : 0;
+ event.editExt.text = text ? SDL_strdup(text) : NULL;
+ event.editExt.start = start;
+ event.editExt.length = length;
+ } else {
+ event.edit.type = SDL_TEXTEDITING;
+ event.edit.windowID = keyboard->focus ? keyboard->focus->id : 0;
+ event.edit.start = start;
+ event.edit.length = length;
+ SDL_utf8strlcpy(event.edit.text, text, SDL_arraysize(event.edit.text));
+ }
+
posted = (SDL_PushEvent(&event) > 0);
}
return (posted);
diff --git a/src/video/SDL_sysvideo.h b/src/video/SDL_sysvideo.h
index 470c14ba352..e2a65045ba7 100644
--- a/src/video/SDL_sysvideo.h
+++ b/src/video/SDL_sysvideo.h
@@ -307,6 +307,8 @@ struct SDL_VideoDevice
void (*StartTextInput) (_THIS);
void (*StopTextInput) (_THIS);
void (*SetTextInputRect) (_THIS, SDL_Rect *rect);
+ void (*ClearComposition) (_THIS);
+ SDL_bool (*IsTextInputShown) (_THIS);
/* Screen keyboard */
SDL_bool (*HasScreenKeyboardSupport) (_THIS);
diff --git a/src/video/SDL_video.c b/src/video/SDL_video.c
index 143f1172b8f..2648c44c6e4 100644
--- a/src/video/SDL_video.c
+++ b/src/video/SDL_video.c
@@ -4135,6 +4135,24 @@ SDL_StartTextInput(void)
}
}
+void
+SDL_ClearComposition(void)
+{
+ if (_this && _this->ClearComposition) {
+ _this->ClearComposition(_this);
+ }
+}
+
+SDL_bool
+SDL_IsTextInputShown(void)
+{
+ if (_this && _this->IsTextInputShown) {
+ return _this->IsTextInputShown(_this);
+ }
+
+ return SDL_FALSE;
+}
+
SDL_bool
SDL_IsTextInputActive(void)
{
diff --git a/src/video/windows/SDL_windowskeyboard.c b/src/video/windows/SDL_windowskeyboard.c
index 6ab440dddfc..d9bd32a81cd 100644
--- a/src/video/windows/SDL_windowskeyboard.c
+++ b/src/video/windows/SDL_windowskeyboard.c
@@ -36,6 +36,8 @@ static void IME_Init(SDL_VideoData *videodata, HWND hwnd);
static void IME_Enable(SDL_VideoData *videodata, HWND hwnd);
static void IME_Disable(SDL_VideoData *videodata, HWND hwnd);
static void IME_Quit(SDL_VideoData *videodata);
+static void IME_ClearComposition(SDL_VideoData *videodata);
+static SDL_bool IME_IsTextInputShown(SDL_VideoData* videodata);
#endif /* !SDL_DISABLE_WINDOWS_IME */
#ifndef MAPVK_VK_TO_VSC
@@ -62,6 +64,8 @@ WIN_InitKeyboard(_THIS)
data->ime_hwnd_main = 0;
data->ime_hwnd_current = 0;
data->ime_himc = 0;
+ data->ime_composition_length = 32 * sizeof(WCHAR);
+ data->ime_composition = (WCHAR*)SDL_malloc(data->ime_composition_length);
data->ime_composition[0] = 0;
data->ime_readingstring[0] = 0;
data->ime_cursor = 0;
@@ -272,6 +276,18 @@ WIN_SetTextInputRect(_THIS, SDL_Rect *rect)
}
}
+void WIN_ClearComposition(_THIS)
+{
+ SDL_VideoData *videodata = (SDL_VideoData *)_this->driverdata;
+ IME_ClearComposition(videodata);
+}
+
+SDL_bool WIN_IsTextInputShown(_THIS)
+{
+ SDL_VideoData* videodata = (SDL_VideoData*)_this->driverdata;
+ return IME_IsTextInputShown(videodata);
+}
+
static SDL_bool
WIN_ShouldShowNativeUI()
{
@@ -742,18 +758,51 @@ IME_ClearComposition(SDL_VideoData *videodata)
SDL_SendEditingText("", 0, 0);
}
+static SDL_bool
+IME_IsTextInputShown(SDL_VideoData* videodata)
+{
+ BOOL result;
+ HIMC himc;
+
+ if (!videodata->ime_initialized || !videodata->ime_available || !videodata->ime_enabled)
+ return SDL_FALSE;
+
+ return videodata->ime_uicontext != 0 ? SDL_TRUE : SDL_FALSE;
+}
+
static void
IME_GetCompositionString(SDL_VideoData *videodata, HIMC himc, DWORD string)
{
- LONG length = ImmGetCompositionStringW(himc, string, videodata->ime_composition, sizeof(videodata->ime_composition) - sizeof(videodata->ime_composition[0]));
+ LONG length;
+ DWORD dwLang = ((DWORD_PTR)videodata->ime_hkl & 0xffff);
+
+ length = ImmGetCompositionStringW(himc, string, NULL, 0);
+ if (length > 0 && videodata->ime_composition_length < length) {
+ if (videodata->ime_composition != NULL)
+ SDL_free(videodata->ime_composition);
+
+ videodata->ime_composition = (WCHAR*)SDL_malloc(length + sizeof(WCHAR));
+ videodata->ime_composition_length = length;
+ }
+
+ length = ImmGetCompositionStringW(
+ himc,
+ string,
+ videodata->ime_composition,
+ videodata->ime_composition_length
+ );
+
if (length < 0)
length = 0;
- length /= sizeof(videodata->ime_composition[0]);
+ length /= sizeof(WCHAR);
videodata->ime_cursor = LOWORD(ImmGetCompositionStringW(himc, GCS_CURSORPOS, 0, 0));
- if (videodata->ime_cursor > 0 &&
- videodata->ime_cursor < SDL_arraysize(videodata->ime_composition) &&
- videodata->ime_composition[videodata->ime_cursor] == 0x3000) {
+ if ((dwLang == LANG_CHT || dwLang == LANG_CHS) &&
+ videodata->ime_cursor > 0 &&
+ videodata->ime_cursor < videodata->ime_composition_length / sizeof(WCHAR) &&
+ (videodata->ime_composition[0] == 0x3000 || videodata->ime_composition[0] == 0x0020)) {
+ // Traditional Chinese IMEs add a placeholder U+3000
+ // Simplified Chinese IMEs seem to add a placholder U+0020 sometimes
int i;
for (i = videodata->ime_cursor + 1; i < length; ++i)
videodata->ime_composition[i - 1] = videodata->ime_composition[i];
@@ -762,6 +811,39 @@ IME_GetCompositionString(SDL_VideoData *videodata, HIMC himc, DWORD string)
}
videodata->ime_composition[length] = 0;
+
+ // Get the correct caret position if we've selected a candidate from the candidate window
+ if (videodata->ime_cursor == 0 && length > 0) {
+ Sint32 start = 0;
+ Sint32 end = 0;
+
+ length = ImmGetCompositionStringW(himc, GCS_COMPATTR, NULL, 0);
+ if (length > 0) {
+ Uint8* attributes = (Uint8*)SDL_malloc(length);
+ ImmGetCompositionString(himc, GCS_COMPATTR, attributes, length);
+
+ for (start = 0; start < length; ++start) {
+ if (attributes[start] == ATTR_TARGET_CONVERTED ||
+ attributes[start] == ATTR_TARGET_NOTCONVERTED)
+ break;
+ }
+
+ for (end = start; end < length; ++end) {
+ if (attributes[end] != ATTR_TARGET_CONVERTED &&
+ attributes[end] != ATTR_TARGET_NOTCONVERTED)
+ break;
+ }
+
+ if (start == length) {
+ start = 0;
+ end = length;
+ }
+
+ SDL_free(attributes);
+ }
+
+ videodata->ime_cursor = end;
+ }
}
static void
@@ -780,22 +862,30 @@ IME_SendInputEvent(SDL_VideoData *videodata)
static void
IME_SendEditingEvent(SDL_VideoData *videodata)
{
- char *s = 0;
- WCHAR buffer[SDL_TEXTEDITINGEVENT_TEXT_SIZE];
- const size_t size = SDL_arraysize(buffer);
- buffer[0] = 0;
+ char *s = NULL;
+ WCHAR *buffer = NULL;
+ size_t size = videodata->ime_composition_length;
if (videodata->ime_readingstring[0]) {
size_t len = SDL_min(SDL_wcslen(videodata->ime_composition), (size_t)videodata->ime_cursor);
+
+ size += sizeof(videodata->ime_readingstring);
+ buffer = (WCHAR*)SDL_malloc(size);
+ buffer[0] = 0;
+
SDL_wcslcpy(buffer, videodata->ime_composition, len + 1);
SDL_wcslcat(buffer, videodata->ime_readingstring, size);
SDL_wcslcat(buffer, &videodata->ime_composition[len], size);
}
else {
+ buffer = (WCHAR*)SDL_malloc(size);
+ buffer[0] = 0;
SDL_wcslcpy(buffer, videodata->ime_composition, size);
}
+
s = WIN_StringToUTF8W(buffer);
SDL_SendEditingText(s, videodata->ime_cursor + (int)SDL_wcslen(videodata->ime_readingstring), 0);
SDL_free(s);
+ SDL_free(buffer);
}
static void
@@ -914,6 +1004,15 @@ IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, SDL_VideoD
return SDL_FALSE;
switch (msg) {
+ case WM_KEYDOWN:
+ if (wParam == VK_PROCESSKEY)
+ {
+ videodata->ime_uicontext = 1;
+ trap = SDL_TRUE;
+ }
+ else
+ videodata->ime_uicontext = 0;
+ break;
case WM_INPUTLANGCHANGE:
IME_InputLangChanged(videodata);
break;
@@ -922,14 +1021,17 @@ IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, SDL_VideoD
*lParam = 0;
}
break;
- case WM_IME_STARTCOMPOSITION:
+ case WM_IME_STARTCOMPOSITION:
+ videodata->ime_suppress_endcomposition_event = SDL_FALSE;
trap = SDL_TRUE;
break;
case WM_IME_COMPOSITION:
trap = SDL_TRUE;
himc = ImmGetContext(hwnd);
if (*lParam & GCS_RESULTSTR) {
+ videodata->ime_suppress_endcomposition_event = SDL_TRUE;
IME_GetCompositionString(videodata, himc, GCS_RESULTSTR);
+ SDL_SendEditingText("", 0, 0);
IME_SendInputEvent(videodata);
}
if (*lParam & GCS_COMPSTR) {
@@ -942,10 +1044,13 @@ IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, SDL_VideoD
ImmReleaseContext(hwnd, himc);
break;
case WM_IME_ENDCOMPOSITION:
+ videodata->ime_uicontext = 0;
videodata->ime_composition[0] = 0;
videodata->ime_readingstring[0] = 0;
videodata->ime_cursor = 0;
- SDL_SendEditingText("", 0, 0);
+ if (videodata->ime_suppress_endcomposition_event == SDL_FALSE)
+ SDL_SendEditingText("", 0, 0);
+ videodata->ime_suppress_endcomposition_event = SDL_FALSE;
break;
case WM_IME_NOTIFY:
switch (wParam) {
@@ -959,10 +1064,12 @@ IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, SDL_VideoD
break;
trap = SDL_TRUE;
+ videodata->ime_uicontext = 1;
IME_GetCandidateList(hwnd, videodata);
break;
case IMN_CLOSECANDIDATE:
trap = SDL_TRUE;
+ videodata->ime_uicontext = 0;
IME_HideCandidateList(videodata);
break;
case IMN_PRIVATE:
diff --git a/src/video/windows/SDL_windowskeyboard.h b/src/video/windows/SDL_windowskeyboard.h
index 76048e78a2c..97382c7bd5d 100644
--- a/src/video/windows/SDL_windowskeyboard.h
+++ b/src/video/windows/SDL_windowskeyboard.h
@@ -32,6 +32,8 @@ extern void WIN_ResetDeadKeys(void);
extern void WIN_StartTextInput(_THIS);
extern void WIN_StopTextInput(_THIS);
extern void WIN_SetTextInputRect(_THIS, SDL_Rect *rect);
+extern void WIN_ClearComposition(_THIS);
+extern SDL_bool WIN_IsTextInputShown(_THIS);
extern SDL_bool IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, struct SDL_VideoData *videodata);
diff --git a/src/video/windows/SDL_windowsvideo.c b/src/video/windows/SDL_windowsvideo.c
index 39806930ba3..4bd2a9831cb 100644
--- a/src/video/windows/SDL_windowsvideo.c
+++ b/src/video/windows/SDL_windowsvideo.c
@@ -216,6 +216,8 @@ WIN_CreateDevice(int devindex)
device->StartTextInput = WIN_StartTextInput;
device->StopTextInput = WIN_StopTextInput;
device->SetTextInputRect = WIN_SetTextInputRect;
+ device->ClearComposition = WIN_ClearComposition;
+ device->IsTextInputShown = WIN_IsTextInputShown;
device->SetClipboardText = WIN_SetClipboardText;
device->GetClipboardText = WIN_GetClipboardText;
diff --git a/src/video/windows/SDL_windowsvideo.h b/src/video/windows/SDL_windowsvideo.h
index daf68e6c2d6..d4208c40500 100644
--- a/src/video/windows/SDL_windowsvideo.h
+++ b/src/video/windows/SDL_windowsvideo.h
@@ -151,9 +151,11 @@ typedef struct SDL_VideoData
SDL_bool ime_available;
HWND ime_hwnd_main;
HWND ime_hwnd_current;
+ SDL_bool ime_suppress_endcomposition_event;
HIMC ime_himc;
- WCHAR ime_composition[SDL_TEXTEDITINGEVENT_TEXT_SIZE];
+ WCHAR* ime_composition;
+ int ime_composition_length;
WCHAR ime_readingstring[16];
int ime_cursor;
@@ -189,6 +191,7 @@ typedef struct SDL_VideoData
DWORD ime_convmodesinkcookie;
TSFSink *ime_uielemsink;
TSFSink *ime_ippasink;
+ LONG ime_uicontext;
BYTE pre_hook_key_state[256];
UINT _SDL_WAKEUP;