libs/ui/Keyboard.cpp

/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#define LOG_TAG "Keyboard"

#include <stdlib.h>
#include <unistd.h>
#include <limits.h>

#include <ui/Keyboard.h>
#include <ui/KeycodeLabels.h>
#include <utils/Errors.h>
#include <utils/Log.h>
#include <cutils/properties.h>

namespace android {

static bool probeKeyMap(KeyMapInfo& keyMapInfo, const String8& keyMapName, bool defaultKeyMap) {
    bool foundOne = false;
    if (keyMapInfo.keyLayoutFile.isEmpty()) {
        keyMapInfo.keyLayoutFile.setTo(getInputDeviceConfigurationFilePath(keyMapName,
                INPUT_DEVICE_CONFIGURATION_FILE_TYPE_KEY_LAYOUT));
        if (!keyMapInfo.keyLayoutFile.isEmpty()) {
            foundOne = true;
        }
    }

    if (keyMapInfo.keyCharacterMapFile.isEmpty()) {
        keyMapInfo.keyCharacterMapFile.setTo(getInputDeviceConfigurationFilePath(keyMapName,
                INPUT_DEVICE_CONFIGURATION_FILE_TYPE_KEY_CHARACTER_MAP));
        if (!keyMapInfo.keyCharacterMapFile.isEmpty()) {
            foundOne = true;
        }
    }

    if (foundOne && defaultKeyMap) {
        keyMapInfo.isDefaultKeyMap = true;
    }
    return keyMapInfo.isComplete();
}

status_t resolveKeyMap(const String8& deviceName,
        const PropertyMap* deviceConfiguration, KeyMapInfo& outKeyMapInfo) {
    // Use the configured key layout if available.
    if (deviceConfiguration) {
        String8 keyLayoutName;
        if (deviceConfiguration->tryGetProperty(String8("keyboard.layout"),
                keyLayoutName)) {
            outKeyMapInfo.keyLayoutFile.setTo(getInputDeviceConfigurationFilePath(
                    keyLayoutName, INPUT_DEVICE_CONFIGURATION_FILE_TYPE_KEY_LAYOUT));
            if (outKeyMapInfo.keyLayoutFile.isEmpty()) {
                LOGW("Configuration for keyboard device '%s' requested keyboard layout '%s' but "
                        "it was not found.",
                        deviceName.string(), keyLayoutName.string());
            }
        }

        String8 keyCharacterMapName;
        if (deviceConfiguration->tryGetProperty(String8("keyboard.characterMap"),
                keyCharacterMapName)) {
            outKeyMapInfo.keyCharacterMapFile.setTo(getInputDeviceConfigurationFilePath(
                    keyCharacterMapName, INPUT_DEVICE_CONFIGURATION_FILE_TYPE_KEY_CHARACTER_MAP));
            if (outKeyMapInfo.keyCharacterMapFile.isEmpty()) {
                LOGW("Configuration for keyboard device '%s' requested keyboard character "
                        "map '%s' but it was not found.",
                        deviceName.string(), keyCharacterMapName.string());
            }
        }

        if (outKeyMapInfo.isComplete()) {
            return OK;
        }
    }

    // Try searching by device name.
    if (probeKeyMap(outKeyMapInfo, deviceName, false)) {
        return OK;
    }

    // Fall back on the Generic key map.
    // TODO Apply some additional heuristics here to figure out what kind of
    //      generic key map to use (US English, etc.).
    if (probeKeyMap(outKeyMapInfo, String8("Generic"), true)) {
        return OK;
    }

    // Give up!
    LOGE("Could not determine key map for device '%s' and the Generic key map was not found!",
            deviceName.string());
    outKeyMapInfo.isDefaultKeyMap = true;
    return NAME_NOT_FOUND;
}

void setKeyboardProperties(int32_t deviceId, const String8& deviceName,
        const KeyMapInfo& keyMapInfo) {
    char propName[PROPERTY_KEY_MAX];
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.devname", deviceId);
    property_set(propName, deviceName.string());
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.klfile", deviceId);
    property_set(propName, keyMapInfo.keyLayoutFile.string());
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.kcmfile", deviceId);
    property_set(propName, keyMapInfo.keyCharacterMapFile.string());
}

void clearKeyboardProperties(int32_t deviceId) {
    char propName[PROPERTY_KEY_MAX];
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.devname", deviceId);
    property_set(propName, "");
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.klfile", deviceId);
    property_set(propName, "");
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.kcmfile", deviceId);
    property_set(propName, "");
}

status_t getKeyCharacterMapFile(int32_t deviceId, String8& outKeyCharacterMapFile) {
    if (deviceId == DEVICE_ID_VIRTUAL_KEYBOARD) {
        outKeyCharacterMapFile.setTo(getInputDeviceConfigurationFilePath(String8("Virtual"),
                INPUT_DEVICE_CONFIGURATION_FILE_TYPE_KEY_CHARACTER_MAP));
        if (!outKeyCharacterMapFile.isEmpty()) {
            return OK;
        }
    }

    char propName[PROPERTY_KEY_MAX];
    char fn[PROPERTY_VALUE_MAX];
    snprintf(propName, sizeof(propName), "hw.keyboards.%u.kcmfile", deviceId);
    if (property_get(propName, fn, "") > 0) {
        outKeyCharacterMapFile.setTo(fn);
        return OK;
    }

    outKeyCharacterMapFile.setTo(getInputDeviceConfigurationFilePath(String8("Generic"),
            INPUT_DEVICE_CONFIGURATION_FILE_TYPE_KEY_CHARACTER_MAP));
    if (!outKeyCharacterMapFile.isEmpty()) {
        return OK;
    }

    LOGE("Can't find any key character map files (also tried Virtual and Generic key maps)");
    return NAME_NOT_FOUND;
}

static int lookupLabel(const char* literal, const KeycodeLabel *list) {
    while (list->literal) {
        if (strcmp(literal, list->literal) == 0) {
            return list->value;
        }
        list++;
    }
    return list->value;
}

int32_t getKeyCodeByLabel(const char* label) {
    return int32_t(lookupLabel(label, KEYCODES));
}

uint32_t getKeyFlagByLabel(const char* label) {
    return uint32_t(lookupLabel(label, FLAGS));
}

static int32_t setEphemeralMetaState(int32_t mask, bool down, int32_t oldMetaState) {
    int32_t newMetaState;
    if (down) {
        newMetaState = oldMetaState | mask;
    } else {
        newMetaState = oldMetaState &
                ~(mask | AMETA_ALT_ON | AMETA_SHIFT_ON | AMETA_CTRL_ON | AMETA_META_ON);
    }

    if (newMetaState & (AMETA_ALT_LEFT_ON | AMETA_ALT_RIGHT_ON)) {
        newMetaState |= AMETA_ALT_ON;
    }

    if (newMetaState & (AMETA_SHIFT_LEFT_ON | AMETA_SHIFT_RIGHT_ON)) {
        newMetaState |= AMETA_SHIFT_ON;
    }

    if (newMetaState & (AMETA_CTRL_LEFT_ON | AMETA_CTRL_RIGHT_ON)) {
        newMetaState |= AMETA_CTRL_ON;
    }

    if (newMetaState & (AMETA_META_LEFT_ON | AMETA_META_RIGHT_ON)) {
        newMetaState |= AMETA_META_ON;
    }
    return newMetaState;
}

static int32_t toggleLockedMetaState(int32_t mask, bool down, int32_t oldMetaState) {
    if (down) {
        return oldMetaState;
    } else {
        return oldMetaState ^ mask;
    }
}

int32_t updateMetaState(int32_t keyCode, bool down, int32_t oldMetaState) {
    int32_t mask;
    switch (keyCode) {
    case AKEYCODE_ALT_LEFT:
        return setEphemeralMetaState(AMETA_ALT_LEFT_ON, down, oldMetaState);
    case AKEYCODE_ALT_RIGHT:
        return setEphemeralMetaState(AMETA_ALT_RIGHT_ON, down, oldMetaState);
    case AKEYCODE_SHIFT_LEFT:
        return setEphemeralMetaState(AMETA_SHIFT_LEFT_ON, down, oldMetaState);
    case AKEYCODE_SHIFT_RIGHT:
        return setEphemeralMetaState(AMETA_SHIFT_RIGHT_ON, down, oldMetaState);
    case AKEYCODE_SYM:
        return setEphemeralMetaState(AMETA_SYM_ON, down, oldMetaState);
    case AKEYCODE_FUNCTION:
        return setEphemeralMetaState(AMETA_FUNCTION_ON, down, oldMetaState);
    case AKEYCODE_CTRL_LEFT:
        return setEphemeralMetaState(AMETA_CTRL_LEFT_ON, down, oldMetaState);
    case AKEYCODE_CTRL_RIGHT:
        return setEphemeralMetaState(AMETA_CTRL_RIGHT_ON, down, oldMetaState);
    case AKEYCODE_META_LEFT:
        return setEphemeralMetaState(AMETA_META_LEFT_ON, down, oldMetaState);
    case AKEYCODE_META_RIGHT:
        return setEphemeralMetaState(AMETA_META_RIGHT_ON, down, oldMetaState);
    case AKEYCODE_CAPS_LOCK:
        return toggleLockedMetaState(AMETA_CAPS_LOCK_ON, down, oldMetaState);
    case AKEYCODE_NUM_LOCK:
        return toggleLockedMetaState(AMETA_NUM_LOCK_ON, down, oldMetaState);
    case AKEYCODE_SCROLL_LOCK:
        return toggleLockedMetaState(AMETA_SCROLL_LOCK_ON, down, oldMetaState);
    default:
        return oldMetaState;
    }
}


} // namespace android