X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/aeaa24d4216076bf3efae08bf66de41ddccd6ca3..493e7eb40cc0ef1ad1bacb1c209ec4020fd9efe9:/src/common/gifdecod.cpp?ds=sidebyside diff --git a/src/common/gifdecod.cpp b/src/common/gifdecod.cpp index 68be026a7b..93cccbabb8 100644 --- a/src/common/gifdecod.cpp +++ b/src/common/gifdecod.cpp @@ -1,5 +1,5 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: gifdecod.cpp +// Name: src/common/gifdecod.cpp // Purpose: wxGIFDecoder, GIF reader for wxImage and wxAnimation // Author: Guillermo Rodriguez Garcia // Version: 3.04 @@ -12,16 +12,15 @@ #include "wx/wxprec.h" #ifdef __BORLANDC__ -# pragma hdrstop + #pragma hdrstop #endif +#if wxUSE_STREAMS && wxUSE_GIF + #ifndef WX_PRECOMP -# include "wx/defs.h" -# include "wx/palette.h" + #include "wx/palette.h" #endif -#if wxUSE_STREAMS && wxUSE_GIF - #include #include #include "wx/gifdecod.h" @@ -41,6 +40,7 @@ GIFImage::GIFImage() delay = -1; p = (unsigned char *) NULL; pal = (unsigned char *) NULL; + ncolours = 0; next = (GIFImage *) NULL; prev = (GIFImage *) NULL; } @@ -122,7 +122,7 @@ bool wxGIFDecoder::ConvertToImage(wxImage *image) const /* set transparent colour mask */ if (transparent != -1) { - for (i = 0; i < 256; i++) + for (i = 0; i < GetNcolours(); i++) { if ((pal[3 * i + 0] == 255) && (pal[3 * i + 1] == 0) && @@ -142,21 +142,18 @@ bool wxGIFDecoder::ConvertToImage(wxImage *image) const image->SetMask(false); #if wxUSE_PALETTE - if (pal) - { - unsigned char r[256]; - unsigned char g[256]; - unsigned char b[256]; - - for (i = 0; i < 256; i++) - { - r[i] = pal[3*i + 0]; - g[i] = pal[3*i + 1]; - b[i] = pal[3*i + 2]; - } + unsigned char r[256]; + unsigned char g[256]; + unsigned char b[256]; - image->SetPalette(wxPalette(256, r, g, b)); + for (i = 0; i < 256; i++) + { + r[i] = pal[3*i + 0]; + g[i] = pal[3*i + 1]; + b[i] = pal[3*i + 2]; } + + image->SetPalette(wxPalette(GetNcolours(), r, g, b)); #endif // wxUSE_PALETTE /* copy image data */ @@ -180,6 +177,7 @@ bool wxGIFDecoder::ConvertToImage(wxImage *image) const int wxGIFDecoder::GetFrameIndex() const { return m_image; } unsigned char* wxGIFDecoder::GetData() const { return (m_pimage->p); } unsigned char* wxGIFDecoder::GetPalette() const { return (m_pimage->pal); } +unsigned int wxGIFDecoder::GetNcolours() const { return (m_pimage->ncolours); } unsigned int wxGIFDecoder::GetWidth() const { return (m_pimage->w); } unsigned int wxGIFDecoder::GetHeight() const { return (m_pimage->h); } unsigned int wxGIFDecoder::GetTop() const { return (m_pimage->top); } @@ -470,6 +468,25 @@ int wxGIFDecoder::dgif(GIFImage *img, int interl, int bits) /* make new entry in alphabet (only if NOT just cleared) */ if (lastcode != -1) { + // Normally, after the alphabet is full and can't grow any + // further (ab_free == 4096), encoder should (must?) emit CLEAR + // to reset it. This checks whether we really got it, otherwise + // the GIF is damaged. + if (ab_free > ab_max) + { + delete[] ab_prefix; + delete[] ab_tail; + delete[] stack; + return wxGIF_INVFORMAT; + } + + // This assert seems unnecessary since the condition above + // eliminates the only case in which it went false. But I really + // don't like being forced to ask "Who in .text could have + // written there?!" And I wouldn't have been forced to ask if + // this line had already been here. + wxASSERT(ab_free < allocSize); + ab_prefix[ab_free] = lastcode; ab_tail[ab_free] = code; ab_free++; @@ -636,7 +653,7 @@ bool wxGIFDecoder::CanRead() // int wxGIFDecoder::ReadGIF() { - unsigned int ncolors; + unsigned int global_ncolors = 0; int bits, interl, transparent, disposal, i; long size; long delay; @@ -675,8 +692,7 @@ int wxGIFDecoder::ReadGIF() m_screenw = buf[0] + 256 * buf[1]; m_screenh = buf[2] + 256 * buf[3]; - const int maxScreenSize = 4 << 10; - if ((m_screenw <= 0) || (m_screenw > maxScreenSize) || (m_screenh <= 0) || (m_screenh > maxScreenSize)) + if ((m_screenw == 0) || (m_screenh == 0)) { return wxGIF_INVFORMAT; } @@ -686,8 +702,8 @@ int wxGIFDecoder::ReadGIF() { m_background = buf[5]; - ncolors = 2 << (buf[4] & 0x07); - size_t numBytes = 3 * ncolors; + global_ncolors = 2 << (buf[4] & 0x07); + size_t numBytes = 3 * global_ncolors; m_f->Read(pal, numBytes); if (m_f->LastRead() != numBytes) { @@ -803,7 +819,7 @@ int wxGIFDecoder::ReadGIF() pimg->w = buf[4] + 256 * buf[5]; pimg->h = buf[6] + 256 * buf[7]; - if ((pimg->w <= 0) || (pimg->w > maxScreenSize) || (pimg->h <= 0) || (pimg->h > maxScreenSize)) + if ((pimg->w == 0) || (pimg->w > m_screenw) || (pimg->h == 0) || (pimg->h > m_screenh)) { Destroy(); return wxGIF_INVFORMAT; @@ -833,11 +849,11 @@ int wxGIFDecoder::ReadGIF() /* load local color map if available, else use global map */ if ((buf[8] & 0x80) == 0x80) { - ncolors = 2 << (buf[8] & 0x07); - size_t numBytes = 3 * ncolors; - if (numBytes > 0) - m_f->Read(pimg->pal, numBytes); - if ((numBytes <= 0) || (m_f->LastRead() != numBytes)) + unsigned int local_ncolors = 2 << (buf[8] & 0x07); + size_t numBytes = 3 * local_ncolors; + m_f->Read(pimg->pal, numBytes); + pimg->ncolours = local_ncolors; + if (m_f->LastRead() != numBytes) { Destroy(); return wxGIF_INVFORMAT; @@ -846,6 +862,7 @@ int wxGIFDecoder::ReadGIF() else { memcpy(pimg->pal, pal, 768); + pimg->ncolours = global_ncolors; } /* get initial code size from first byte in raster data */ @@ -915,15 +932,9 @@ int wxGIFDecoder::ReadGIF() /* local color map */ if ((buf[8] & 0x80) == 0x80) { - ncolors = 2 << (buf[8] & 0x07); - if (ncolors <= 0) - { - Destroy(); - return wxGIF_INVFORMAT; - } - + unsigned int local_ncolors = 2 << (buf[8] & 0x07); wxFileOffset pos = m_f->TellI(); - wxFileOffset numBytes = 3 * ncolors; + wxFileOffset numBytes = 3 * local_ncolors; m_f->SeekI(numBytes, wxFromCurrent); if (m_f->TellI() != (pos + numBytes)) {