识别和匹配idc配置文件

转自http://blog.csdn.net/coldsnow33/article/details/16808161

1. void EventHub::loadConfigurationLocked(Device* device) {  
2.     device->configurationFile = getInputDeviceConfigurationFilePathByDeviceIdentifier(  
3.             device->identifier, INPUT_DEVICE_CONFIGURATION_FILE_TYPE_CONFIGURATION);//get IDC文件  
4.     if (device->configurationFile.isEmpty()) {  
5.         ALOGD("No input device configuration file found for device '%s'.",  
6.                 device->identifier.name.string());  
7.     } else {  
8.         status_t status = PropertyMap::load(device->configurationFile,  
9.                 &device->configuration);//找到配置文件，解析出来保存到device->configuration中  
10.         if (status) {//解析出错，  
11.             ALOGE("Error loading input device configuration file for device '%s'.  "  
12.                     "Using default configuration.",  
13.                     device->identifier.name.string());  
14.         }  
15.     }  
16. }  
17. 

18. void EventHub::loadConfigurationLocked(Device* device) {    device->configurationFile = getInputDeviceConfigurationFilePathByDeviceIdentifier(            device->identifier, INPUT_DEVICE_CONFIGURATION_FILE_TYPE_CONFIGURATION);//get IDC文件    if (device->configurationFile.isEmpty()) {        ALOGD("No input device configuration file found for device '%s'.",                device->identifier.name.string());    } else {        status_t status = PropertyMap::load(device->configurationFile,                &device->configuration);//找到配置文件，解析出来保存到device->configuration中        if (status) {//解析出错，            ALOGE("Error loading input device configuration file for device '%s'.  "                    "Using default configuration.",                    device->identifier.name.string());        }    }}

[cpp] view plain copy print?

1. String8 getInputDeviceConfigurationFilePathByDeviceIdentifier(  
2.         const InputDeviceIdentifier& deviceIdentifier,  
3.         InputDeviceConfigurationFileType type) {  
4.     if (deviceIdentifier.vendor !=0 && deviceIdentifier.product != 0) {  
5.         if (deviceIdentifier.version != 0) {  
6.             // Try vendor product version.  
7.             String8 versionPath(getInputDeviceConfigurationFilePathByName(  
8.                     String8::format("Vendor_%04x_Product_%04x_Version_%04x",  
9.                             deviceIdentifier.vendor, deviceIdentifier.product,  
10.                             deviceIdentifier.version),  
11.                     type));  
12.             if (!versionPath.isEmpty()) {  
13.                 return versionPath;  
14.             }  
15.         }  
16.   
17.         // Try vendor product.  
18.         String8 productPath(getInputDeviceConfigurationFilePathByName(  
19.                 String8::format("Vendor_%04x_Product_%04x",  
20.                         deviceIdentifier.vendor, deviceIdentifier.product),  
21.                 type));  
22.         if (!productPath.isEmpty()) {  
23.             return productPath;  
24.         }  
25.     }  
26.   
27.     // Try device name.  
28.     return getInputDeviceConfigurationFilePathByName(deviceIdentifier.name, type);  
29. }  

String8 getInputDeviceConfigurationFilePathByDeviceIdentifier(        const InputDeviceIdentifier& deviceIdentifier,        InputDeviceConfigurationFileType type) {    if (deviceIdentifier.vendor !=0 && deviceIdentifier.product != 0) {        if (deviceIdentifier.version != 0) {            // Try vendor product version.            String8 versionPath(getInputDeviceConfigurationFilePathByName(                    String8::format("Vendor_%04x_Product_%04x_Version_%04x",                            deviceIdentifier.vendor, deviceIdentifier.product,                            deviceIdentifier.version),                    type));            if (!versionPath.isEmpty()) {                return versionPath;            }        }        // Try vendor product.        String8 productPath(getInputDeviceConfigurationFilePathByName(                String8::format("Vendor_%04x_Product_%04x",                        deviceIdentifier.vendor, deviceIdentifier.product),                type));        if (!productPath.isEmpty()) {            return productPath;        }    }    // Try device name.    return getInputDeviceConfigurationFilePathByName(deviceIdentifier.name, type);}

[cpp] view plain copy print?

1. String8 getInputDeviceConfigurationFilePathByName(  
2.         const String8& name, InputDeviceConfigurationFileType type) {  
3.     // Search system repository.  
4.     String8 path;  
5.     path.setTo(getenv("ANDROID_ROOT"));  
6.     path.append("/usr/");  
7.     appendInputDeviceConfigurationFileRelativePath(path, name, type);  
8. #if DEBUG_PROBE  
9.     ALOGD("Probing for system provided input device configuration file: path='%s'", path.string());  
10. #endif  
11.     if (!access(path.string(), R_OK)) {  
12. #if DEBUG_PROBE  
13.         ALOGD("Found");  
14. #endif  
15.         return path;  
16.     }  
17.   
18.     // Search user repository.  
19.     // TODO Should only look here if not in safe mode.  
20.     path.setTo(getenv("ANDROID_DATA"));  
21.     path.append("/system/devices/");  
22.     appendInputDeviceConfigurationFileRelativePath(path, name, type);  
23. #if DEBUG_PROBE  
24.     ALOGD("Probing for system user input device configuration file: path='%s'", path.string());  
25. #endif  
26.     if (!access(path.string(), R_OK)) {  
27. #if DEBUG_PROBE  
28.         ALOGD("Found");  
29. #endif  
30.         return path;  
31.     }  
32.   
33.     // Not found.  
34. #if DEBUG_PROBE  
35.     ALOGD("Probe failed to find input device configuration file: name='%s', type=%d",  
36.             name.string(), type);  
37. #endif  
38.     return String8();  
39. }  

String8 getInputDeviceConfigurationFilePathByName(        const String8& name, InputDeviceConfigurationFileType type) {    // Search system repository.    String8 path;    path.setTo(getenv("ANDROID_ROOT"));    path.append("/usr/");    appendInputDeviceConfigurationFileRelativePath(path, name, type);#if DEBUG_PROBE    ALOGD("Probing for system provided input device configuration file: path='%s'", path.string());#endif    if (!access(path.string(), R_OK)) {#if DEBUG_PROBE        ALOGD("Found");#endif        return path;    }    // Search user repository.    // TODO Should only look here if not in safe mode.    path.setTo(getenv("ANDROID_DATA"));    path.append("/system/devices/");    appendInputDeviceConfigurationFileRelativePath(path, name, type);#if DEBUG_PROBE    ALOGD("Probing for system user input device configuration file: path='%s'", path.string());#endif    if (!access(path.string(), R_OK)) {#if DEBUG_PROBE        ALOGD("Found");#endif        return path;    }    // Not found.#if DEBUG_PROBE    ALOGD("Probe failed to find input device configuration file: name='%s', type=%d",            name.string(), type);#endif    return String8();}

这里出现了两个环境变量：
echo $ANDROID_ROOT /system
echo $ANDROID_DATA /data
识别和匹配配置文件的顺序为：
/system/usr/idc/Vendor_XXXX_Product_XXXX_Version_XXXX.idc
/data/system/devices/idc/Vendor_XXXX_Product_XXXX_Version_XXXX.idc
/system/usr/idc/Vendor_XXXX_Product_XXXX.idc
/data/system/devices/idc/Vendor_XXXX_Product_XXXX.idc
/system/usr/idc/DEVICE_NAME.idc
/data/system/devices/idc/DEVICE_NAME.idc
需要注意的是文件名中的数字需要小写。例如
input_dev­>id.vendor = 0xDEAD;
input_dev­>id.product = 0xBEEF;
input_dev­>id.version = 0x0102;
对应的配置文件名应该是Vendor_dead_Product_beef_Version_0102.idc或者Vendor_dead_Product_beef.idc。
获取配置文件名的时候，如果发现文件名中含有不是ascii(<=0x7f)的字符；或者是ascii，但不是数字，不是希腊字母，也不是“-”和“_”，比如说空格、tab等，就要转成字符'_'。所以dumpsys input看到的ConfigurationFile: /system/usr/idc/Vendor_dead_Product_beef.idc，也许和我们定义的有点不一样，那就是定义了非法字符，被转了。只要找到ConfigurationFile就可以了。