jsxdrapi.c

来自「一个基于alice开发的机器人」· C语言 代码 · 共 691 行 · 第 1/2 页

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code, released
 * March 31, 1998.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */
#include "jsstddef.h"
#include "jsconfig.h"

#if JS_HAS_XDR

#include <string.h>
#include "jstypes.h"
#include "jsutil.h" /* Added by JSIFY */
#include "jsdhash.h"
#include "jsprf.h"
#include "jsapi.h"
#include "jscntxt.h"
#include "jsobj.h"              /* js_XDRObject */
#include "jsscript.h"           /* js_XDRScript */
#include "jsstr.h"
#include "jsxdrapi.h"

#ifdef DEBUG
#define DBG(x) x
#else
#define DBG(x) ((void)0)
#endif

typedef struct JSXDRMemState {
    JSXDRState  state;
    char        *base;
    uint32      count;
    uint32      limit;
} JSXDRMemState;

#define MEM_BLOCK       8192
#define MEM_PRIV(xdr)   ((JSXDRMemState *)(xdr))

#define MEM_BASE(xdr)   (MEM_PRIV(xdr)->base)
#define MEM_COUNT(xdr)  (MEM_PRIV(xdr)->count)
#define MEM_LIMIT(xdr)  (MEM_PRIV(xdr)->limit)

#define MEM_LEFT(xdr, bytes)                                                  \
    JS_BEGIN_MACRO                                                            \
        if ((xdr)->mode == JSXDR_DECODE &&                                    \
            MEM_COUNT(xdr) + bytes > MEM_LIMIT(xdr)) {                        \
            JS_ReportErrorNumber((xdr)->cx, js_GetErrorMessage, NULL,         \
                                 JSMSG_END_OF_DATA);                          \
            return 0;                                                         \
        }                                                                     \
    JS_END_MACRO

#define MEM_NEED(xdr, bytes)                                                  \
    JS_BEGIN_MACRO                                                            \
        if ((xdr)->mode == JSXDR_ENCODE) {                                    \
            if (MEM_LIMIT(xdr) &&                                             \
                MEM_COUNT(xdr) + bytes > MEM_LIMIT(xdr)) {                    \
                uint32 limit_ = JS_ROUNDUP(MEM_COUNT(xdr) + bytes, MEM_BLOCK);\
                void *data_ = JS_realloc((xdr)->cx, MEM_BASE(xdr), limit_);   \
                if (!data_)                                                   \
                    return 0;                                                 \
                MEM_BASE(xdr) = data_;                                        \
                MEM_LIMIT(xdr) = limit_;                                      \
            }                                                                 \
        } else {                                                              \
            MEM_LEFT(xdr, bytes);                                             \
        }                                                                     \
    JS_END_MACRO

#define MEM_DATA(xdr)        ((void *)(MEM_BASE(xdr) + MEM_COUNT(xdr)))
#define MEM_INCR(xdr,bytes)  (MEM_COUNT(xdr) += (bytes))

static JSBool
mem_get32(JSXDRState *xdr, uint32 *lp)
{
    MEM_LEFT(xdr, 4);
    *lp = *(uint32 *)MEM_DATA(xdr);
    MEM_INCR(xdr, 4);
    return JS_TRUE;
}

static JSBool
mem_set32(JSXDRState *xdr, uint32 *lp)
{
    MEM_NEED(xdr, 4);
    *(uint32 *)MEM_DATA(xdr) = *lp;
    MEM_INCR(xdr, 4);
    return JS_TRUE;
}

static JSBool
mem_getbytes(JSXDRState *xdr, char *bytes, uint32 len)
{
    MEM_LEFT(xdr, len);
    memcpy(bytes, MEM_DATA(xdr), len);
    MEM_INCR(xdr, len);
    return JS_TRUE;
}

static JSBool
mem_setbytes(JSXDRState *xdr, char *bytes, uint32 len)
{
    MEM_NEED(xdr, len);
    memcpy(MEM_DATA(xdr), bytes, len);
    MEM_INCR(xdr, len);
    return JS_TRUE;
}

static void *
mem_raw(JSXDRState *xdr, uint32 len)
{
    void *data;
    if (xdr->mode == JSXDR_ENCODE) {
        MEM_NEED(xdr, len);
    } else if (xdr->mode == JSXDR_DECODE) {
        MEM_LEFT(xdr, len);
    }
    data = MEM_DATA(xdr);
    MEM_INCR(xdr, len);
    return data;
}

static JSBool
mem_seek(JSXDRState *xdr, int32 offset, JSXDRWhence whence)
{
    switch (whence) {
      case JSXDR_SEEK_CUR:
        if ((int32)MEM_COUNT(xdr) + offset < 0) {
            JS_ReportErrorNumber(xdr->cx, js_GetErrorMessage, NULL,
                                 JSMSG_SEEK_BEYOND_START);
            return JS_FALSE;
        }
        if (offset > 0)
            MEM_NEED(xdr, offset);
        MEM_COUNT(xdr) += offset;
        return JS_TRUE;
      case JSXDR_SEEK_SET:
        if (offset < 0) {
            JS_ReportErrorNumber(xdr->cx, js_GetErrorMessage, NULL,
                                 JSMSG_SEEK_BEYOND_START);
            return JS_FALSE;
        }
        if (xdr->mode == JSXDR_ENCODE) {
            if ((uint32)offset > MEM_COUNT(xdr))
                MEM_NEED(xdr, offset - MEM_COUNT(xdr));
            MEM_COUNT(xdr) = offset;
        } else {
            if ((uint32)offset > MEM_LIMIT(xdr)) {
                JS_ReportErrorNumber(xdr->cx, js_GetErrorMessage, NULL,
                                     JSMSG_SEEK_BEYOND_END);
                return JS_FALSE;
            }
            MEM_COUNT(xdr) = offset;
        }
        return JS_TRUE;
      case JSXDR_SEEK_END:
        if (offset >= 0 ||
            xdr->mode == JSXDR_ENCODE ||
            (int32)MEM_LIMIT(xdr) + offset < 0) {
            JS_ReportErrorNumber(xdr->cx, js_GetErrorMessage, NULL,
                                 JSMSG_END_SEEK);
            return JS_FALSE;
        }
        MEM_COUNT(xdr) = MEM_LIMIT(xdr) + offset;
        return JS_TRUE;
      default: {
        char numBuf[12];
        JS_snprintf(numBuf, sizeof numBuf, "%d", whence);
        JS_ReportErrorNumber(xdr->cx, js_GetErrorMessage, NULL,
                             JSMSG_WHITHER_WHENCE, numBuf);
        return JS_FALSE;
      }
    }
}

static uint32
mem_tell(JSXDRState *xdr)
{
    return MEM_COUNT(xdr);
}

static void
mem_finalize(JSXDRState *xdr)
{
    JS_free(xdr->cx, MEM_BASE(xdr));
}

static JSXDROps xdrmem_ops = {
    mem_get32,      mem_set32,      mem_getbytes,   mem_setbytes,
    mem_raw,        mem_seek,       mem_tell,       mem_finalize
};

JS_PUBLIC_API(void)
JS_XDRInitBase(JSXDRState *xdr, JSXDRMode mode, JSContext *cx)
{
    xdr->mode = mode;
    xdr->cx = cx;
    xdr->registry = NULL;
    xdr->numclasses = xdr->maxclasses = 0;
    xdr->reghash = NULL;
    xdr->userdata = NULL;
}

JS_PUBLIC_API(JSXDRState *)
JS_XDRNewMem(JSContext *cx, JSXDRMode mode)
{
    JSXDRState *xdr = (JSXDRState *) JS_malloc(cx, sizeof(JSXDRMemState));
    if (!xdr)
        return NULL;
    JS_XDRInitBase(xdr, mode, cx);
    if (mode == JSXDR_ENCODE) {
        if (!(MEM_BASE(xdr) = JS_malloc(cx, MEM_BLOCK))) {
            JS_free(cx, xdr);
            return NULL;
        }
    } else {
        /* XXXbe ok, so better not deref MEM_BASE(xdr) if not ENCODE */
        MEM_BASE(xdr) = NULL;
    }
    xdr->ops = &xdrmem_ops;
    MEM_COUNT(xdr) = 0;
    MEM_LIMIT(xdr) = MEM_BLOCK;
    return xdr;
}

JS_PUBLIC_API(void *)
JS_XDRMemGetData(JSXDRState *xdr, uint32 *lp)
{
    if (xdr->ops != &xdrmem_ops)
        return NULL;
    *lp = MEM_COUNT(xdr);
    return MEM_BASE(xdr);
}

JS_PUBLIC_API(void)
JS_XDRMemSetData(JSXDRState *xdr, void *data, uint32 len)
{
    if (xdr->ops != &xdrmem_ops)
        return;
    MEM_LIMIT(xdr) = len;
    MEM_BASE(xdr) = data;
    MEM_COUNT(xdr) = 0;
}

JS_PUBLIC_API(uint32)
JS_XDRMemDataLeft(JSXDRState *xdr)
{
    if (xdr->ops != &xdrmem_ops)
        return 0;
    return MEM_LIMIT(xdr) - MEM_COUNT(xdr);
}

JS_PUBLIC_API(void)
JS_XDRMemResetData(JSXDRState *xdr)
{
    if (xdr->ops != &xdrmem_ops)
        return;
    MEM_COUNT(xdr) = 0;
}

JS_PUBLIC_API(void)
JS_XDRDestroy(JSXDRState *xdr)
{
    JSContext *cx = xdr->cx;
    xdr->ops->finalize(xdr);
    if (xdr->registry) {
        JS_free(cx, xdr->registry);
        if (xdr->reghash)
            JS_DHashTableDestroy(xdr->reghash);
    }
    JS_free(cx, xdr);
}

JS_PUBLIC_API(JSBool)
JS_XDRUint8(JSXDRState *xdr, uint8 *b)
{
    uint32 l = *b;
    if (!JS_XDRUint32(xdr, &l))
        return JS_FALSE;
    *b = (uint8) l;
    return JS_TRUE;
}

JS_PUBLIC_API(JSBool)
JS_XDRUint16(JSXDRState *xdr, uint16 *s)
{
    uint32 l = *s;
    if (!JS_XDRUint32(xdr, &l))
        return JS_FALSE;
    *s = (uint16) l;
    return JS_TRUE;
}

JS_PUBLIC_API(JSBool)
JS_XDRUint32(JSXDRState *xdr, uint32 *lp)
{
    JSBool ok = JS_TRUE;
    if (xdr->mode == JSXDR_ENCODE) {
        uint32 xl = JSXDR_SWAB32(*lp);
        ok = xdr->ops->set32(xdr, &xl);
    } else if (xdr->mode == JSXDR_DECODE) {
        ok = xdr->ops->get32(xdr, lp);
        *lp = JSXDR_SWAB32(*lp);
    }
    return ok;
}

JS_PUBLIC_API(JSBool)
JS_XDRBytes(JSXDRState *xdr, char *bytes, uint32 len)
{
    uint32 padlen;
    static char padbuf[JSXDR_ALIGN-1];