jsj_utils.c

caffeine-monkey java实现的js模拟引擎

            return;
        err_jsstr = JS_NewString(cx, err, strlen(err));
        if (!err_jsstr)
            return;
        JS_SetPendingException(cx, STRING_TO_JSVAL(err_jsstr));
        return;
    }

    
    (*jEnv)->ExceptionClear(jEnv);
    
    /* Check for JSException */
    if (njJSException && 
        (*jEnv)->IsInstanceOf(jEnv, java_exception, njJSException)) {
        
        wrapped_exception_type = 
            (*jEnv)->GetIntField(jEnv, java_exception,
            njJSException_wrappedExceptionType);
        
        /* (int) to suppress warning */
        if ((int)wrapped_exception_type != JSTYPE_EMPTY) {
            java_obj = 
                (*jEnv)->GetObjectField(jEnv, java_exception, 
                njJSException_wrappedException);
            
            if ((java_obj == NULL) && 
                (wrapped_exception_type == JSTYPE_OBJECT)) {
                js_exception = JSVAL_NULL;
            } else { 
                java_class = (*jEnv)->GetObjectClass(jEnv, java_obj); 
                class_descriptor = jsj_GetJavaClassDescriptor(cx, jEnv, java_class);
                /* OK to delete ref, since above call adds global ref */
                (*jEnv)->DeleteLocalRef(jEnv, java_class);  
                
                /* Convert native JS values back to native types. */
                switch(wrapped_exception_type) {
                case JSTYPE_NUMBER:
                    if (!jsj_ConvertJavaObjectToJSNumber(cx, jEnv,
                        class_descriptor,
                        java_obj, 
                        &js_exception))
                        goto error;
                    break;
                case JSTYPE_BOOLEAN:
                    if (!jsj_ConvertJavaObjectToJSBoolean(cx, jEnv,
                        class_descriptor,
                        java_obj, 
                        &js_exception))
                        goto error;
                    break;
                case JSTYPE_STRING:
                    if (!jsj_ConvertJavaObjectToJSString(cx, jEnv,
                        class_descriptor,
                        java_obj, 
                        &js_exception))
                        goto error;
                    break;
                case JSTYPE_VOID:
                    js_exception = JSVAL_VOID;
                    break;
                case JSTYPE_OBJECT:
                case JSTYPE_FUNCTION:
                default:
                    if ((*jEnv)->IsInstanceOf(jEnv, java_obj, njJSObject)) {
                        js_exception = OBJECT_TO_JSVAL(jsj_UnwrapJSObjectWrapper(jEnv, java_obj));
                        if (!js_exception)
                            goto error;                        
                    } else {
                        if (!jsj_ConvertJavaObjectToJSValue(cx, jEnv, java_obj, 
                            &js_exception)) 
                            goto error;
                    }
                }
            }
        }
        /* Check for internal exception */
    } else {
        if (!JSJ_ConvertJavaObjectToJSValue(cx, java_exception,
            &js_exception)) {
            goto error;
        }
    }
    
    /* Set pending JS exception and clear the java exception. */
    JS_SetPendingException(cx, js_exception);                        
    goto done;

error:
    
    JS_ASSERT(0);
    jsj_LogError("Out of memory while attempting to throw JSException\n");
    
done:
    if (class_descriptor)
        jsj_ReleaseJavaClassDescriptor(cx, jEnv, class_descriptor);
    if (java_obj)
        (*jEnv)->DeleteLocalRef(jEnv, java_obj);
    if (java_exception)
        (*jEnv)->DeleteLocalRef(jEnv, java_exception);
}

void
jsj_ReportJavaError(JSContext *cx, JNIEnv *env, const char *format, ...)
{
    va_list ap;

    va_start(ap, format);
    vreport_java_error(cx, env, format, ap);
    va_end(ap);
}

/*
 * Same as jsj_ReportJavaError, except "internal error: " is prepended
 * to message.
 */
void
jsj_UnexpectedJavaError(JSContext *cx, JNIEnv *env, const char *format, ...)
{
    va_list ap;
    const char *format2;

    va_start(ap, format);
    format2 = JS_smprintf("internal error: %s", format);
    if (format2) {
        vreport_java_error(cx, env, format2, ap);
        free((void*)format2);
    }
    va_end(ap);
}

/*
 * Most LiveConnect errors are signaled by calling JS_ReportError(),
 * but in some circumstances, the target JSContext for such errors
 * is not determinable, e.g. during initialization.  In such cases
 * any error messages are routed to this function.
 */
void
jsj_LogError(const char *error_msg)
{
    if (JSJ_callbacks && JSJ_callbacks->error_print)
        JSJ_callbacks->error_print(error_msg);
    else
        fputs(error_msg, stderr);
}

/*
        Error number handling. 

        jsj_ErrorFormatString is an array of format strings mapped
        by error number. It is initialized by the contents of jsj.msg

        jsj_GetErrorMessage is invoked by the engine whenever it wants 
        to convert an error number into an error format string.
*/
/*
        this define needs to go somewhere sensible
*/
#define JSJ_HAS_DFLT_MSG_STRINGS 1

JSErrorFormatString jsj_ErrorFormatString[JSJ_Err_Limit] = {
#if JSJ_HAS_DFLT_MSG_STRINGS
#define MSG_DEF(name, number, count, format) \
    { format, count } ,
#else
#define MSG_DEF(name, number, count, format) \
    { NULL, count } ,
#endif
#include "jsj.msg"
#undef MSG_DEF
};

const JSErrorFormatString *
jsj_GetErrorMessage(void *userRef, const char *locale, const uintN errorNumber)
{
    if ((errorNumber > 0) && (errorNumber < JSJ_Err_Limit))
            return &jsj_ErrorFormatString[errorNumber];
        else
            return NULL;
}

jsize
jsj_GetJavaArrayLength(JSContext *cx, JNIEnv *jEnv, jarray java_array)
{
    jsize array_length = (*jEnv)->GetArrayLength(jEnv, java_array);
    jthrowable java_exception = (*jEnv)->ExceptionOccurred(jEnv);
    if (java_exception) {
        jsj_UnexpectedJavaError(cx, jEnv, "Couldn't obtain array length");
        (*jEnv)->DeleteLocalRef(jEnv, java_exception);
        return -1;
    }
    return array_length;
}

static JSJavaThreadState *the_java_jsj_env = NULL;

JSJavaThreadState *
jsj_EnterJava(JSContext *cx, JNIEnv **envp)
{
    JSJavaThreadState *jsj_env;
    char *err_msg;

    *envp = NULL;
    err_msg = NULL;

    jsj_env = the_java_jsj_env;
    if (jsj_env == NULL && JSJ_callbacks && JSJ_callbacks->map_js_context_to_jsj_thread)
        jsj_env = JSJ_callbacks->map_js_context_to_jsj_thread(cx, &err_msg);
    if (!jsj_env) {
        if (err_msg) {
            JS_ReportError(cx, err_msg);
            free(err_msg);
        }
        return NULL;
    }

    /* simultaneous calls from different JSContext are not allowed */
    if ((jsj_env->recursion_depth > 0) && (jsj_env->cx != cx))
        return NULL;

    jsj_env->recursion_depth++;

    /* bug #60018:  prevent dangling pointer to JSContext */
    if (!jsj_env->cx)
        jsj_env->cx = cx;

    if (envp)
        *envp = jsj_env->jEnv;
    return jsj_env;
}

extern void
jsj_ExitJava(JSJavaThreadState *jsj_env)
{
    jsj_JSIsCallingApplet = JS_FALSE;
    if (jsj_env) {
        JS_ASSERT(jsj_env->recursion_depth > 0);
        if (--jsj_env->recursion_depth == 0)
            jsj_env->cx = NULL;
    }
}

/**
 * Since only one Java thread is allowed to enter JavaScript, this function is
 * used to enforce the use of that thread's state. The static global the_java_jsj_env
 * overrides using JSJ_callbacks->map_js_context_to_jsj_thread, which maps
 * native threads to JSJavaThreadStates. This isn't appropriate when Java calls
 * JavaScript, as there can be a many to one mapping from Java threads to native
 * threads.
 */
JSJavaThreadState *
jsj_SetJavaJSJEnv(JSJavaThreadState* java_jsj_env)
{
    JSJavaThreadState *old_jsj_env = the_java_jsj_env;
    the_java_jsj_env = java_jsj_env;
    return old_jsj_env;
}