Fixed bug 2824 - Add Fcitx Input Method Support

Weitian Leung Just moved ibus direct call to SDL_IME_* related functions, and adds fcitx IME support (uses DBus, too), enable with env: SDL_IM_MODULE=fcitx (ibus still the default one)
2016-10-07 18:57:40 -07:00 · 2016-10-07 18:57:40 -07:00 · de631d20e4
commit de631d20e4
parent d14ce58e75
10 changed files with 967 additions and 22 deletions
--- a/src/core/linux/SDL_fcitx.c
+++ b/src/core/linux/SDL_fcitx.c
@ -0,0 +1,548 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include <fcitx/frontend.h>
+#include <unistd.h>
+
+#include "SDL_fcitx.h"
+#include "SDL_keycode.h"
+#include "SDL_keyboard.h"
+#include "../../events/SDL_keyboard_c.h"
+#include "SDL_dbus.h"
+#include "SDL_syswm.h"
+#if SDL_VIDEO_DRIVER_X11
+#  include "../../video/x11/SDL_x11video.h"
+#endif
+#include "SDL_hints.h"
+
+#define FCITX_DBUS_SERVICE "org.fcitx.Fcitx"
+
+#define FCITX_IM_DBUS_PATH "/inputmethod"
+#define FCITX_IC_DBUS_PATH "/inputcontext_%d"
+
+#define FCITX_IM_DBUS_INTERFACE "org.fcitx.Fcitx.InputMethod"
+#define FCITX_IC_DBUS_INTERFACE "org.fcitx.Fcitx.InputContext"
+
+#define IC_NAME_MAX 64
+#define DBUS_TIMEOUT 500
+
+typedef struct _FcitxClient
+{
+    SDL_DBusContext *dbus;
+
+    char servicename[IC_NAME_MAX];
+    char icname[IC_NAME_MAX];
+
+    int id;
+
+    SDL_Rect cursor_rect;
+} FcitxClient;
+
+static FcitxClient fcitx_client;
+
+static int
+GetDisplayNumber()
+{
+    const char *display = SDL_getenv("DISPLAY");
+    const char *p = NULL;;
+    int number = 0;
+
+    if (display == NULL)
+        return 0;
+
+    display = SDL_strchr(display, ':');
+    if (display == NULL)
+        return 0;
+
+    display++;
+    p = SDL_strchr(display, '.');
+    if (p == NULL && display != NULL) {
+        number = SDL_strtod(display, NULL);
+    } else {
+        char *buffer = SDL_strdup(display);
+        buffer[p - display] = '\0';
+        number = SDL_strtod(buffer, NULL);
+        SDL_free(buffer);
+    }
+
+    return number;
+}
+
+static char*
+GetAppName()
+{
+#if defined(__LINUX__) || defined(__FREEBSD__)
+    char *spot;
+    char procfile[1024];
+    char linkfile[1024];
+    int linksize;
+
+#if defined(__LINUX__)
+    SDL_snprintf(procfile, sizeof(procfile), "/proc/%d/exe", getpid());
+#elif defined(__FREEBSD__)
+    SDL_snprintf(procfile, sizeof(procfile), "/proc/%d/file", getpid());
+#endif
+    linksize = readlink(procfile, linkfile, sizeof(linkfile) - 1);
+    if (linksize > 0) {
+        linkfile[linksize] = '\0';
+        spot = SDL_strrchr(linkfile, '/');
+        if (spot) {
+            return SDL_strdup(spot + 1);
+        } else {
+            return SDL_strdup(linkfile);
+        }
+    }
+#endif /* __LINUX__ || __FREEBSD__ */
+
+    return SDL_strdup("SDL_App");
+}
+
+/*
+ * Copied from fcitx source
+ */
+#define CONT(i)   ISUTF8_CB(in[i])
+#define VAL(i, s) ((in[i]&0x3f) << s)
+
+static char *
+_fcitx_utf8_get_char(const char *i, uint32_t *chr)
+{
+    const unsigned char* in = (const unsigned char *)i;
+    if (!(in[0] & 0x80)) {
+        *(chr) = *(in);
+        return (char *)in + 1;
+    }
+
+    /* 2-byte, 0x80-0x7ff */
+    if ((in[0] & 0xe0) == 0xc0 && CONT(1)) {
+        *chr = ((in[0] & 0x1f) << 6) | VAL(1, 0);
+        return (char *)in + 2;
+    }
+
+    /* 3-byte, 0x800-0xffff */
+    if ((in[0] & 0xf0) == 0xe0 && CONT(1) && CONT(2)) {
+        *chr = ((in[0] & 0xf) << 12) | VAL(1, 6) | VAL(2, 0);
+        return (char *)in + 3;
+    }
+
+    /* 4-byte, 0x10000-0x1FFFFF */
+    if ((in[0] & 0xf8) == 0xf0 && CONT(1) && CONT(2) && CONT(3)) {
+        *chr = ((in[0] & 0x7) << 18) | VAL(1, 12) | VAL(2, 6) | VAL(3, 0);
+        return (char *)in + 4;
+    }
+
+    /* 5-byte, 0x200000-0x3FFFFFF */
+    if ((in[0] & 0xfc) == 0xf8 && CONT(1) && CONT(2) && CONT(3) && CONT(4)) {
+        *chr = ((in[0] & 0x3) << 24) | VAL(1, 18) | VAL(2, 12) | VAL(3, 6) | VAL(4, 0);
+        return (char *)in + 5;
+    }
+
+    /* 6-byte, 0x400000-0x7FFFFFF */
+    if ((in[0] & 0xfe) == 0xfc && CONT(1) && CONT(2) && CONT(3) && CONT(4) && CONT(5)) {
+        *chr = ((in[0] & 0x1) << 30) | VAL(1, 24) | VAL(2, 18) | VAL(3, 12) | VAL(4, 6) | VAL(5, 0);
+        return (char *)in + 6;
+    }
+
+    *chr = *in;
+
+    return (char *)in + 1;
+}
+
+static size_t
+_fcitx_utf8_strlen(const char *s)
+{
+    unsigned int l = 0;
+
+    while (*s) {
+        uint32_t chr;
+
+        s = _fcitx_utf8_get_char(s, &chr);
+        l++;
+    }
+
+    return l;
+}
+
+static DBusHandlerResult
+DBus_MessageFilter(DBusConnection *conn, DBusMessage *msg, void *data)
+{
+    SDL_DBusContext *dbus = (SDL_DBusContext *)data;
+
+    if (dbus->message_is_signal(msg, FCITX_IC_DBUS_INTERFACE, "CommitString")) {
+        DBusMessageIter iter;
+        const char *text = NULL;
+
+        dbus->message_iter_init(msg, &iter);
+        dbus->message_iter_get_basic(&iter, &text);
+
+        if (text)
+            SDL_SendKeyboardText(text);
+
+        return DBUS_HANDLER_RESULT_HANDLED;
+    }
+
+    if (dbus->message_is_signal(msg, FCITX_IC_DBUS_INTERFACE, "UpdatePreedit")) {
+        DBusMessageIter iter;
+        const char *text;
+
+        dbus->message_iter_init(msg, &iter);
+        dbus->message_iter_get_basic(&iter, &text);
+
+        if (text && *text) {
+            char buf[SDL_TEXTEDITINGEVENT_TEXT_SIZE];
+            size_t text_bytes = SDL_strlen(text), i = 0;
+            size_t cursor = 0;
+
+            while (i < text_bytes) {
+                size_t sz = SDL_utf8strlcpy(buf, text + i, sizeof(buf));
+                size_t chars = _fcitx_utf8_strlen(buf);
+
+                SDL_SendEditingText(buf, cursor, chars);
+
+                i += sz;
+                cursor += chars;
+            }
+        }
+
+        SDL_Fcitx_UpdateTextRect(NULL);
+        return DBUS_HANDLER_RESULT_HANDLED;
+    }
+
+    return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static DBusMessage*
+FcitxClientICNewMethod(FcitxClient *client,
+        const char *method)
+{
+    SDL_DBusContext *dbus = client->dbus;
+    return dbus->message_new_method_call(
+            client->servicename,
+            client->icname,
+            FCITX_IC_DBUS_INTERFACE,
+            method);
+}
+
+static void
+FcitxClientICCallMethod(FcitxClient *client,
+        const char *method)
+{
+    SDL_DBusContext *dbus = client->dbus;
+    DBusMessage *msg = FcitxClientICNewMethod(client, method);
+
+    if (msg == NULL)
+        return ;
+
+    if (dbus->connection_send(dbus->session_conn, msg, NULL)) {
+        dbus->connection_flush(dbus->session_conn);
+    }
+
+    dbus->message_unref(msg);
+}
+
+static void
+Fcitx_SetCapabilities(void *data,
+        const char *name,
+        const char *old_val,
+        const char *internal_editing)
+{
+    FcitxClient *client = (FcitxClient *)data;
+    SDL_DBusContext *dbus = client->dbus;
+    Uint32 caps = CAPACITY_NONE;
+
+    DBusMessage *msg = FcitxClientICNewMethod(client, "SetCapacity");
+    if (msg == NULL)
+        return ;
+
+    if (!(internal_editing && *internal_editing == '1')) {
+        caps |= CAPACITY_PREEDIT;
+    }
+
+    dbus->message_append_args(msg,
+            DBUS_TYPE_UINT32, &caps,
+            DBUS_TYPE_INVALID);
+    if (dbus->connection_send(dbus->session_conn, msg, NULL)) {
+        dbus->connection_flush(dbus->session_conn);
+    }
+
+    dbus->message_unref(msg);
+}
+
+static void
+FcitxClientCreateIC(FcitxClient *client)
+{
+    char *appname = NULL;
+    pid_t pid = 0;
+    int id = 0;
+    SDL_bool enable;
+    Uint32 arg1, arg2, arg3, arg4;
+
+    SDL_DBusContext *dbus = client->dbus;
+    DBusMessage *reply = NULL;
+    DBusMessage *msg = dbus->message_new_method_call(
+            client->servicename,
+            FCITX_IM_DBUS_PATH,
+            FCITX_IM_DBUS_INTERFACE,
+            "CreateICv3"
+            );
+
+    if (msg == NULL)
+        return ;
+
+    appname = GetAppName();
+    pid = getpid();
+    dbus->message_append_args(msg,
+            DBUS_TYPE_STRING, &appname,
+            DBUS_TYPE_INT32, &pid,
+            DBUS_TYPE_INVALID);
+
+    do {
+        reply = dbus->connection_send_with_reply_and_block(
+                dbus->session_conn,
+                msg,
+                DBUS_TIMEOUT,
+                NULL);
+
+        if (!reply)
+            break;
+        if (!dbus->message_get_args(reply, NULL,
+                DBUS_TYPE_INT32, &id,
+                DBUS_TYPE_BOOLEAN, &enable,
+                DBUS_TYPE_UINT32, &arg1,
+                DBUS_TYPE_UINT32, &arg2,
+                DBUS_TYPE_UINT32, &arg3,
+                DBUS_TYPE_UINT32, &arg4,
+                DBUS_TYPE_INVALID))
+            break;
+
+        if (id < 0)
+            break;
+        client->id = id;
+
+        SDL_snprintf(client->icname, IC_NAME_MAX,
+                FCITX_IC_DBUS_PATH, client->id);
+
+        dbus->bus_add_match(dbus->session_conn,
+                "type='signal', interface='org.fcitx.Fcitx.InputContext'",
+                NULL);
+        dbus->connection_add_filter(dbus->session_conn,
+                &DBus_MessageFilter, dbus,
+                NULL);
+        dbus->connection_flush(dbus->session_conn);
+
+        SDL_AddHintCallback(SDL_HINT_IME_INTERNAL_EDITING, &Fcitx_SetCapabilities, client);
+    }
+    while (0);
+
+    if (reply)
+        dbus->message_unref(reply);
+    dbus->message_unref(msg);
+    SDL_free(appname);
+}
+
+static Uint32
+Fcitx_ModState(void)
+{
+    Uint32 fcitx_mods = 0;
+    SDL_Keymod sdl_mods = SDL_GetModState();
+
+    if (sdl_mods & KMOD_SHIFT) fcitx_mods |= FcitxKeyState_Shift;
+    if (sdl_mods & KMOD_CAPS)   fcitx_mods |= FcitxKeyState_CapsLock;
+    if (sdl_mods & KMOD_CTRL)  fcitx_mods |= FcitxKeyState_Ctrl;
+    if (sdl_mods & KMOD_ALT)   fcitx_mods |= FcitxKeyState_Alt;
+    if (sdl_mods & KMOD_NUM)    fcitx_mods |= FcitxKeyState_NumLock;
+    if (sdl_mods & KMOD_LGUI)   fcitx_mods |= FcitxKeyState_Super;
+    if (sdl_mods & KMOD_RGUI)   fcitx_mods |= FcitxKeyState_Meta;
+
+    return fcitx_mods;
+}
+
+SDL_bool
+SDL_Fcitx_Init()
+{
+    fcitx_client.dbus = SDL_DBus_GetContext();
+
+    fcitx_client.cursor_rect.x = -1;
+    fcitx_client.cursor_rect.y = -1;
+    fcitx_client.cursor_rect.w = 0;
+    fcitx_client.cursor_rect.h = 0;
+
+    SDL_snprintf(fcitx_client.servicename, IC_NAME_MAX,
+            "%s-%d",
+            FCITX_DBUS_SERVICE, GetDisplayNumber());
+
+    FcitxClientCreateIC(&fcitx_client);
+
+    return SDL_TRUE;
+}
+
+void
+SDL_Fcitx_Quit()
+{
+    FcitxClientICCallMethod(&fcitx_client, "DestroyIC");
+}
+
+void
+SDL_Fcitx_SetFocus(SDL_bool focused)
+{
+    if (focused) {
+        FcitxClientICCallMethod(&fcitx_client, "FocusIn");
+    } else {
+        FcitxClientICCallMethod(&fcitx_client, "FocusOut");
+    }
+}
+
+void
+SDL_Fcitx_Reset(void)
+{
+    FcitxClientICCallMethod(&fcitx_client, "Reset");
+    FcitxClientICCallMethod(&fcitx_client, "CloseIC");
+}
+
+SDL_bool
+SDL_Fcitx_ProcessKeyEvent(Uint32 keysym, Uint32 keycode)
+{
+    DBusMessage *msg = NULL;
+    DBusMessage *reply = NULL;
+    SDL_DBusContext *dbus = fcitx_client.dbus;
+
+    Uint32 state = 0;
+    SDL_bool handled = SDL_FALSE;
+    int type = FCITX_PRESS_KEY;
+    Uint32 event_time = 0;
+
+    msg = FcitxClientICNewMethod(&fcitx_client, "ProcessKeyEvent");
+    if (msg == NULL)
+        return SDL_FALSE;
+
+    state = Fcitx_ModState();
+    dbus->message_append_args(msg,
+            DBUS_TYPE_UINT32, &keysym,
+            DBUS_TYPE_UINT32, &keycode,
+            DBUS_TYPE_UINT32, &state,
+            DBUS_TYPE_INT32, &type,
+            DBUS_TYPE_UINT32, &event_time,
+            DBUS_TYPE_INVALID);
+
+    reply = dbus->connection_send_with_reply_and_block(dbus->session_conn,
+            msg,
+            -1,
+            NULL);
+
+    if (reply) {
+        dbus->message_get_args(reply,
+                NULL,
+                DBUS_TYPE_INT32, &handled,
+                DBUS_TYPE_INVALID);
+
+        dbus->message_unref(reply);
+    }
+
+    if (handled) {
+        SDL_Fcitx_UpdateTextRect(NULL);
+    }
+
+    return handled;
+}
+
+void
+SDL_Fcitx_UpdateTextRect(SDL_Rect *rect)
+{
+    SDL_Window *focused_win = NULL;
+    SDL_SysWMinfo info;
+    int x = 0, y = 0;
+    SDL_Rect *cursor = &fcitx_client.cursor_rect;
+
+    SDL_DBusContext *dbus = fcitx_client.dbus;
+    DBusMessage *msg = NULL;
+    DBusConnection *conn;
+
+    if (rect) {
+        SDL_memcpy(cursor, rect, sizeof(SDL_Rect));
+    }
+
+    focused_win = SDL_GetKeyboardFocus();
+    if (!focused_win) {
+        return ;
+    }
+
+    SDL_VERSION(&info.version);
+    if (!SDL_GetWindowWMInfo(focused_win, &info)) {
+        return;
+    }
+
+    SDL_GetWindowPosition(focused_win, &x, &y);
+
+#if SDL_VIDEO_DRIVER_X11
+    if (info.subsystem == SDL_SYSWM_X11) {
+        SDL_DisplayData *displaydata = (SDL_DisplayData *) SDL_GetDisplayForWindow(focused_win)->driverdata;
+
+        Display *x_disp = info.info.x11.display;
+        Window x_win = info.info.x11.window;
+        int x_screen = displaydata->screen;
+        Window unused;
+        X11_XTranslateCoordinates(x_disp, x_win, RootWindow(x_disp, x_screen), 0, 0, &x, &y, &unused);
+    }
+#endif
+
+    if (cursor->x == -1 && cursor->y == -1 && cursor->w == 0 && cursor->h == 0) {
+        // move to bottom left
+        int w = 0, h = 0;
+        SDL_GetWindowSize(focused_win, &w, &h);
+        cursor->x = 0;
+        cursor->y = h;
+    }
+
+    x += cursor->x;
+    y += cursor->y;
+
+    msg = FcitxClientICNewMethod(&fcitx_client, "SetCursorRect");
+    if (msg == NULL)
+        return ;
+
+    dbus->message_append_args(msg,
+            DBUS_TYPE_INT32, &x,
+            DBUS_TYPE_INT32, &y,
+            DBUS_TYPE_INT32, &cursor->w,
+            DBUS_TYPE_INT32, &cursor->h,
+            DBUS_TYPE_INVALID);
+
+    conn = dbus->session_conn;
+    if (dbus->connection_send(conn, msg, NULL))
+        dbus->connection_flush(conn);
+
+    dbus->message_unref(msg);
+}
+
+void
+SDL_Fcitx_PumpEvents()
+{
+    SDL_DBusContext *dbus = fcitx_client.dbus;
+    DBusConnection *conn = dbus->session_conn;
+
+    dbus->connection_read_write(conn, 0);
+
+    while (dbus->connection_dispatch(conn) == DBUS_DISPATCH_DATA_REMAINS) {
+        /* Do nothing, actual work happens in DBus_MessageFilter */
+        usleep(10);
+    }
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
--- a/src/core/linux/SDL_fcitx.h
+++ b/src/core/linux/SDL_fcitx.h
@ -0,0 +1,40 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef _SDL_fcitx_h
+#define _SDL_fcitx_h
+
+#include "../../SDL_internal.h"
+
+#include "SDL_stdinc.h"
+#include "SDL_rect.h"
+
+extern SDL_bool SDL_Fcitx_Init(void);
+extern void SDL_Fcitx_Quit(void);
+extern void SDL_Fcitx_SetFocus(SDL_bool focused);
+extern void SDL_Fcitx_Reset(void);
+extern SDL_bool SDL_Fcitx_ProcessKeyEvent(Uint32 keysym, Uint32 keycode);
+extern void SDL_Fcitx_UpdateTextRect(SDL_Rect *rect);
+extern void SDL_Fcitx_PumpEvents();
+
+#endif /* _SDL_fcitx_h */
+
+/* vi: set ts=4 sw=4 expandtab: */
--- a/src/core/linux/SDL_ime.c
+++ b/src/core/linux/SDL_ime.c
@ -0,0 +1,135 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_ime.h"
+#include "SDL_ibus.h"
+#include "SDL_fcitx.h"
+
+typedef SDL_bool (*_SDL_IME_Init)();
+typedef void (*_SDL_IME_Quit)();
+typedef void (*_SDL_IME_SetFocus)(SDL_bool);
+typedef void (*_SDL_IME_Reset)();
+typedef SDL_bool (*_SDL_IME_ProcessKeyEvent)(Uint32, Uint32);
+typedef void (*_SDL_IME_UpdateTextRect)(SDL_Rect *);
+typedef void (*_SDL_IME_PumpEvents)();
+
+static _SDL_IME_Init SDL_IME_Init_Real = NULL;
+static _SDL_IME_Quit SDL_IME_Quit_Real = NULL;
+static _SDL_IME_SetFocus SDL_IME_SetFocus_Real = NULL;
+static _SDL_IME_Reset SDL_IME_Reset_Real = NULL;
+static _SDL_IME_ProcessKeyEvent SDL_IME_ProcessKeyEvent_Real = NULL;
+static _SDL_IME_UpdateTextRect SDL_IME_UpdateTextRect_Real = NULL;
+static _SDL_IME_PumpEvents SDL_IME_PumpEvents_Real = NULL;
+
+static void
+InitIME()
+{
+    static SDL_bool inited = SDL_FALSE;
+    const char *im_module = NULL;
+
+    if (inited == SDL_TRUE)
+        return ;
+
+    inited = SDL_TRUE;
+    // TODO:
+    // better move every ime implenment to a shared library
+
+    // default to IBus
+#ifdef HAVE_IBUS_IBUS_H
+    SDL_IME_Init_Real = SDL_IBus_Init;
+    SDL_IME_Quit_Real = SDL_IBus_Quit;
+    SDL_IME_SetFocus_Real = SDL_IBus_SetFocus;
+    SDL_IME_Reset_Real = SDL_IBus_Reset;
+    SDL_IME_ProcessKeyEvent_Real = SDL_IBus_ProcessKeyEvent;
+    SDL_IME_UpdateTextRect_Real = SDL_IBus_UpdateTextRect;
+    SDL_IME_PumpEvents_Real = SDL_IBus_PumpEvents;
+#endif
+
+    im_module = SDL_getenv("SDL_IM_MODULE");
+    if (im_module) {
+        if (SDL_strcmp(im_module, "fcitx") == 0) {
+#ifdef HAVE_FCITX_FRONTEND_H
+            SDL_IME_Init_Real = SDL_Fcitx_Init;
+            SDL_IME_Quit_Real = SDL_Fcitx_Quit;
+            SDL_IME_SetFocus_Real = SDL_Fcitx_SetFocus;
+            SDL_IME_Reset_Real = SDL_Fcitx_Reset;
+            SDL_IME_ProcessKeyEvent_Real = SDL_Fcitx_ProcessKeyEvent;
+            SDL_IME_UpdateTextRect_Real = SDL_Fcitx_UpdateTextRect;
+            SDL_IME_PumpEvents_Real = SDL_Fcitx_PumpEvents;
+#endif
+        }
+    }
+}
+
+SDL_bool
+SDL_IME_Init(void)
+{
+    InitIME();
+
+    if (SDL_IME_Init_Real)
+        return SDL_IME_Init_Real();
+
+    return SDL_FALSE;
+}
+
+void
+SDL_IME_Quit(void)
+{
+    if (SDL_IME_Quit_Real)
+        SDL_IME_Quit_Real();
+}
+
+void
+SDL_IME_SetFocus(SDL_bool focused)
+{
+    if (SDL_IME_SetFocus_Real)
+        SDL_IME_SetFocus_Real(focused);
+}
+
+void
+SDL_IME_Reset(void)
+{
+    if (SDL_IME_Reset_Real)
+        SDL_IME_Reset_Real();
+}
+
+SDL_bool
+SDL_IME_ProcessKeyEvent(Uint32 keysym, Uint32 keycode)
+{
+    if (SDL_IME_ProcessKeyEvent_Real)
+        return SDL_IME_ProcessKeyEvent_Real(keysym, keycode);
+
+    return SDL_FALSE;
+}
+
+void
+SDL_IME_UpdateTextRect(SDL_Rect *rect)
+{
+    if (SDL_IME_UpdateTextRect_Real)
+        SDL_IME_UpdateTextRect_Real(rect);
+}
+
+void
+SDL_IME_PumpEvents()
+{
+    if (SDL_IME_PumpEvents_Real)
+        SDL_IME_PumpEvents_Real();
+}
--- a/src/core/linux/SDL_ime.h
+++ b/src/core/linux/SDL_ime.h
@ -0,0 +1,38 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef _SDL_ime_h
+#define _SDL_ime_h
+
+#include "../../SDL_internal.h"
+
+#include "SDL_stdinc.h"
+#include "SDL_rect.h"
+
+extern SDL_bool SDL_IME_Init();
+extern void SDL_IME_Quit();
+extern void SDL_IME_SetFocus(SDL_bool focused);
+extern void SDL_IME_Reset();
+extern SDL_bool SDL_IME_ProcessKeyEvent(Uint32 keysym, Uint32 keycode);
+extern void SDL_IME_UpdateTextRect(SDL_Rect *rect);
+extern void SDL_IME_PumpEvents();
+
+#endif /* _SDL_ime_h */