bjson.c

/*
 * QuickJS: binary JSON module (test only)
 * 
 * Copyright (c) 2017-2019 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "quickjs-libc.h"
#include "cutils.h"

static JSValue js_bjson_read(JSContext *ctx, JSValueConst this_val,
                             int argc, JSValueConst *argv)
{
    uint8_t *buf;
    uint64_t pos, len;
    JSValue obj;
    size_t size;
    
    if (JS_ToIndex(ctx, &pos, argv[1]))
        return JS_EXCEPTION;
    if (JS_ToIndex(ctx, &len, argv[2]))
        return JS_EXCEPTION;
    buf = JS_GetArrayBuffer(ctx, &size, argv[0]);
    if (!buf)
        return JS_EXCEPTION;
    if (pos + len > size)
        return JS_ThrowRangeError(ctx, "array buffer overflow");
    obj = JS_ReadObject(ctx, buf + pos, len, 0);
    return obj;
}

static JSValue js_bjson_write(JSContext *ctx, JSValueConst this_val,
                              int argc, JSValueConst *argv)
{
    size_t len;
    uint8_t *buf;
    JSValue array;
    
    buf = JS_WriteObject(ctx, &len, argv[0], 0);
    if (!buf)
        return JS_EXCEPTION;
    array = JS_NewArrayBufferCopy(ctx, buf, len);
    js_free(ctx, buf);
    return array;
}

static const JSCFunctionListEntry js_bjson_funcs[] = {
    JS_CFUNC_DEF("read", 3, js_bjson_read ),
    JS_CFUNC_DEF("write", 1, js_bjson_write ),
};

static int js_bjson_init(JSContext *ctx, JSModuleDef *m)
{
    return JS_SetModuleExportList(ctx, m, js_bjson_funcs,
                                  countof(js_bjson_funcs));
}

#ifdef JS_SHARED_LIBRARY
#define JS_INIT_MODULE js_init_module
#else
#define JS_INIT_MODULE js_init_module_bjson
#endif

JSModuleDef *JS_INIT_MODULE(JSContext *ctx, const char *module_name)
{
    JSModuleDef *m;
    m = JS_NewCModule(ctx, module_name, js_bjson_init);
    if (!m)
        return NULL;
    JS_AddModuleExportList(ctx, m, js_bjson_funcs, countof(js_bjson_funcs));
    return m;
}