core/src/fxcodec/codec/fx_codec_gif.cpp

// Copyright 2014 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com

#include "../../../include/fxcodec/fx_codec.h"
#include "../../../include/fxge/fx_dib.h"
#include "codec_int.h"
#include "../lgif/fx_gif.h"
struct FXGIF_Context {
    gif_decompress_struct_p gif_ptr;
    void*		parent_ptr;
    void*		child_ptr;

    void*		(*m_AllocFunc)(unsigned int);
    void		(*m_FreeFunc)(void*);
};
extern "C" {
    static void* _gif_alloc_func(unsigned int size)
    {
        return FX_Alloc(char, size);
    }
    static void  _gif_free_func(void* p)
    {
        if(p != NULL) {
            FX_Free(p);
        }
    }
};
static void _gif_error_data(gif_decompress_struct_p gif_ptr, FX_LPCSTR err_msg)
{
    FXSYS_strncpy((char*)gif_ptr->err_ptr, err_msg, GIF_MAX_ERROR_SIZE - 1);
    longjmp(gif_ptr->jmpbuf, 1);
}
static FX_LPBYTE _gif_ask_buf_for_pal(gif_decompress_struct_p gif_ptr, FX_INT32 pal_size)
{
    FXGIF_Context* p = (FXGIF_Context*)gif_ptr->context_ptr;
    CCodec_GifModule* pModule = (CCodec_GifModule*)p->parent_ptr;
    return pModule->AskLocalPaletteBufCallback(p->child_ptr,
            _gif_get_frame_num(gif_ptr),
            pal_size);
}
static void _gif_record_current_position(gif_decompress_struct_p gif_ptr, FX_DWORD* cur_pos_ptr)
{
    FXGIF_Context* p = (FXGIF_Context*)gif_ptr->context_ptr;
    CCodec_GifModule* pModule = (CCodec_GifModule*)p->parent_ptr;
    pModule->RecordCurrentPositionCallback(p->child_ptr, *cur_pos_ptr);
}
static void _gif_read_scanline(gif_decompress_struct_p gif_ptr, FX_INT32 row_num, FX_LPBYTE row_buf)
{
    FXGIF_Context* p = (FXGIF_Context*)gif_ptr->context_ptr;
    CCodec_GifModule* pModule = (CCodec_GifModule*)p->parent_ptr;
    pModule->ReadScanlineCallback(p->child_ptr, row_num, row_buf);
}
static FX_BOOL _gif_get_record_position(gif_decompress_struct_p gif_ptr, FX_DWORD cur_pos,
                                        FX_INT32 left, FX_INT32 top, FX_INT32 width, FX_INT32 height,
                                        FX_INT32 pal_num, void* pal_ptr,
                                        FX_INT32 delay_time, FX_BOOL user_input,
                                        FX_INT32 trans_index, FX_INT32 disposal_method, FX_BOOL interlace)
{
    FXGIF_Context* p = (FXGIF_Context*)gif_ptr->context_ptr;
    CCodec_GifModule* pModule = (CCodec_GifModule*)p->parent_ptr;
    return pModule->InputRecordPositionBufCallback(p->child_ptr, cur_pos, FX_RECT(left, top, left + width, top + height),
            pal_num, pal_ptr, delay_time, user_input, trans_index, disposal_method, interlace);
}
void* CCodec_GifModule::Start(void* pModule)
{
    FXGIF_Context* p = (FXGIF_Context*)FX_Alloc(FX_BYTE, sizeof(FXGIF_Context));
    if (p == NULL) {
        return NULL;
    }
    FXSYS_memset32(p, 0, sizeof(FXGIF_Context));
    p->m_AllocFunc = _gif_alloc_func;
    p->m_FreeFunc = _gif_free_func;
    p->gif_ptr = NULL;
    p->parent_ptr = (void*)this;
    p->child_ptr = pModule;
    p->gif_ptr = _gif_create_decompress();
    if (p->gif_ptr == NULL) {
        FX_Free(p);
        return NULL;
    }
    p->gif_ptr->context_ptr = (void*)p;
    p->gif_ptr->err_ptr = m_szLastError;
    p->gif_ptr->_gif_error_fn = _gif_error_data;
    p->gif_ptr->_gif_ask_buf_for_pal_fn = _gif_ask_buf_for_pal;
    p->gif_ptr->_gif_record_current_position_fn = _gif_record_current_position;
    p->gif_ptr->_gif_get_row_fn = _gif_read_scanline;
    p->gif_ptr->_gif_get_record_position_fn = _gif_get_record_position;
    return p;
}
void CCodec_GifModule::Finish(void* pContext)
{
    FXGIF_Context* p = (FXGIF_Context*)pContext;
    if(p != NULL) {
        _gif_destroy_decompress(&p->gif_ptr);
        p->m_FreeFunc(p);
    }
}
FX_INT32 CCodec_GifModule::ReadHeader(void* pContext, int* width, int* height,
                                      int* pal_num, void** pal_pp, int* bg_index, CFX_DIBAttribute* pAttribute)
{
    FXGIF_Context* p = (FXGIF_Context*)pContext;
    if(setjmp(p->gif_ptr->jmpbuf)) {
        return 0;
    }
    FX_INT32 ret = _gif_read_header(p->gif_ptr);
    if (ret != 1) {
        return ret;
    }
    if (pAttribute) {
    }
    *width = p->gif_ptr->width;
    *height = p->gif_ptr->height;
    *pal_num = p->gif_ptr->global_pal_num;
    *pal_pp = p->gif_ptr->global_pal_ptr;
    *bg_index = p->gif_ptr->bc_index;
    return 1;
}
FX_INT32 CCodec_GifModule::LoadFrameInfo(void* pContext, int* frame_num)
{
    FXGIF_Context* p = (FXGIF_Context*)pContext;
    if(setjmp(p->gif_ptr->jmpbuf)) {
        return 0;
    }
    FX_INT32 ret = _gif_get_frame(p->gif_ptr);
    if (ret != 1) {
        return ret;
    }
    *frame_num = _gif_get_frame_num(p->gif_ptr);
    return 1;
}
FX_INT32 CCodec_GifModule::LoadFrame(void* pContext, int frame_num, CFX_DIBAttribute* pAttribute)
{
    FXGIF_Context* p = (FXGIF_Context*)pContext;
    if(setjmp(p->gif_ptr->jmpbuf)) {
        return 0;
    }
    FX_INT32 ret = _gif_load_frame(p->gif_ptr, frame_num);
    if (ret == 1) {
        if (pAttribute) {
            pAttribute->m_nGifLeft = p->gif_ptr->img_ptr_arr_ptr->GetAt(frame_num)->image_info_ptr->left;
            pAttribute->m_nGifTop = p->gif_ptr->img_ptr_arr_ptr->GetAt(frame_num)->image_info_ptr->top;
            pAttribute->m_fAspectRatio = p->gif_ptr->pixel_aspect;
            if (p->gif_ptr->cmt_data_ptr) {
                FX_LPCBYTE buf = (FX_LPCBYTE)p->gif_ptr->cmt_data_ptr->GetBuffer(0);
                FX_DWORD len = p->gif_ptr->cmt_data_ptr->GetLength();
                if (len > 21) {
                    FX_BYTE size = *buf++;
                    if (size) {
                        pAttribute->m_strAuthor = CFX_ByteString(buf, size);
                    } else {
                        pAttribute->m_strAuthor.Empty();
                    }
                    buf += size;
                    size = *buf++;
                    if (size == 20) {
                        FXSYS_memcpy32(pAttribute->m_strTime, buf, size);
                    }
                }
            }
        }
    }
    return ret;
}
FX_DWORD CCodec_GifModule::GetAvailInput(void* pContext, FX_LPBYTE* avial_buf_ptr)
{
    FXGIF_Context* p = (FXGIF_Context*)pContext;
    return _gif_get_avail_input(p->gif_ptr, avial_buf_ptr);
}
void CCodec_GifModule::Input(void* pContext, FX_LPCBYTE src_buf, FX_DWORD src_size)
{
    FXGIF_Context* p = (FXGIF_Context*)pContext;
    _gif_input_buffer(p->gif_ptr, (FX_LPBYTE)src_buf, src_size);
}