android 浏览器插件开发 － Log

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    android中的插件开发中的示例代码已经给我们说明了如何打log，参看示例代码main.cpp

    for (int i = 0; i < argc; i++) {        if (!strcmp(argn[i], "DrawingModel")) {            if (!strcmp(argv[i], "Bitmap")) {                model = kBitmap_ANPDrawingModel;            }               else if (!strcmp(argv[i], "Surface")) {               model = kSurface_ANPDrawingModel;            }               gLogI.log(kDebug_ANPLogType, "------ %p DrawingModel is %d", instance, model);            break;        }       }   

    我们可以使用gLogI.log打印调试信息。

    gLogI的定义如下

ANPLogInterfaceV0           gLogI;

     ANPLogInterfaceV0的定义如下(Android_npapi.h)

struct ANPLogInterfaceV0 : ANPInterface {    /** dumps printf messages to the log file        e.g. interface->log(instance, kWarning_ANPLogType, "value is %d", value);     */    void (*log)(ANPLogType, const char format[], ...);};

       该结构的赋值如下（ANPLogInterface.cpp）

static void anp_log(ANPLogType logType, const char format[], ...) {    va_list args;    va_start(args, format);    android_LogPriority priority;    switch (logType) {        case kError_ANPLogType:            priority = ANDROID_LOG_ERROR;            break;        case kWarning_ANPLogType:            priority = ANDROID_LOG_WARN;            break;        case kDebug_ANPLogType:            priority = ANDROID_LOG_DEBUG;            break;        default:            priority = ANDROID_LOG_UNKNOWN;            break;    }    LOG_PRI_VA(priority, "plugin", format, args);    va_end(args);}void ANPLogInterfaceV0_Init(ANPInterface* value) {    ANPLogInterfaceV0* i = reinterpret_cast<ANPLogInterfaceV0*>(value);    i->log = anp_log;}

    而LOG_PRI_VA的调用关系如下 

[e-mail]_vprintLog@Log.h __android_log_vprint@Log.h__android_log_write@logd_write.cwrite_to_log@logd_write.c__write_to_log_init@logd_write.c__write_to_log_kernel@logd_write.cwritev@uio.c

    注：

    1. 插件的打印信息的channel为plugin

    2. android系统据我所知，只有如下log会受到是否打开DEBUG的影响

         LOGV*  LOG_FATAL*