#include <stdlib.h>
#include <string.h>
#include "wx/gifdecod.h"
+#include "wx/scopedptr.h"
+#include "wx/scopeguard.h"
// def ctor
GIFImage();
- unsigned int w; /* width */
- unsigned int h; /* height */
- unsigned int left; /* x coord (in logical screen) */
- unsigned int top; /* y coord (in logical screen) */
- int transparent; /* transparent color index (-1 = none) */
- wxAnimationDisposal disposal; /* disposal method */
- long delay; /* delay in ms (-1 = unused) */
- unsigned char *p; /* bitmap */
- unsigned char *pal; /* palette */
- unsigned int ncolours; /* number of colours */
-
- DECLARE_NO_COPY_CLASS(GIFImage)
+ unsigned int w; // width
+ unsigned int h; // height
+ unsigned int left; // x coord (in logical screen)
+ unsigned int top; // y coord (in logical screen)
+ int transparent; // transparent color index (-1 = none)
+ wxAnimationDisposal disposal; // disposal method
+ long delay; // delay in ms (-1 = unused)
+ unsigned char *p; // bitmap
+ unsigned char *pal; // palette
+ unsigned int ncolours; // number of colours
+
+ wxDECLARE_NO_COPY_CLASS(GIFImage);
};
+wxDECLARE_SCOPED_PTR(GIFImage, GIFImagePtr)
+wxDEFINE_SCOPED_PTR(GIFImage, GIFImagePtr)
//---------------------------------------------------------------------------
void wxGIFDecoder::Destroy()
{
wxASSERT(m_nFrames==m_frames.GetCount());
- for (size_t i=0; i<m_nFrames; i++)
+ for (unsigned int i=0; i<m_nFrames; i++)
{
GIFImage *f = (GIFImage*)m_frames[i];
free(f->p);
// This function was designed by Vaclav Slavik
-bool wxGIFDecoder::ConvertToImage(size_t frame, wxImage *image) const
+bool wxGIFDecoder::ConvertToImage(unsigned int frame, wxImage *image) const
{
unsigned char *src, *dst, *pal;
unsigned long i;
int transparent;
- /* just in case... */
+ // just in case...
image->Destroy();
- /* create the image */
+ // create the image
wxSize sz = GetFrameSize(frame);
image->Create(sz.GetWidth(), sz.GetHeight());
+ image->SetType(wxBITMAP_TYPE_GIF);
if (!image->Ok())
return false;
dst = image->GetData();
transparent = GetTransparentColourIndex(frame);
- /* set transparent colour mask */
+ // set transparent colour mask
if (transparent != -1)
{
for (i = 0; i < GetNcolours(frame); i++)
image->SetPalette(wxPalette(GetNcolours(frame), r, g, b));
#endif // wxUSE_PALETTE
- /* copy image data */
+ // copy image data
unsigned long npixel = sz.GetWidth() * sz.GetHeight();
for (i = 0; i < npixel; i++, src++)
{
// Get data for current frame
-wxSize wxGIFDecoder::GetFrameSize(size_t frame) const
+wxSize wxGIFDecoder::GetFrameSize(unsigned int frame) const
{
return wxSize(GetFrame(frame)->w, GetFrame(frame)->h);
}
-wxPoint wxGIFDecoder::GetFramePosition(size_t frame) const
+wxPoint wxGIFDecoder::GetFramePosition(unsigned int frame) const
{
return wxPoint(GetFrame(frame)->left, GetFrame(frame)->top);
}
-wxAnimationDisposal wxGIFDecoder::GetDisposalMethod(size_t frame) const
+wxAnimationDisposal wxGIFDecoder::GetDisposalMethod(unsigned int frame) const
{
return GetFrame(frame)->disposal;
}
-long wxGIFDecoder::GetDelay(size_t frame) const
+long wxGIFDecoder::GetDelay(unsigned int frame) const
{
return GetFrame(frame)->delay;
}
-wxColour wxGIFDecoder::GetTransparentColour(size_t frame) const
+wxColour wxGIFDecoder::GetTransparentColour(unsigned int frame) const
{
unsigned char *pal = GetFrame(frame)->pal;
int n = GetFrame(frame)->transparent;
pal[n*3 + 2]);
}
-unsigned char* wxGIFDecoder::GetData(size_t frame) const { return (GetFrame(frame)->p); }
-unsigned char* wxGIFDecoder::GetPalette(size_t frame) const { return (GetFrame(frame)->pal); }
-unsigned int wxGIFDecoder::GetNcolours(size_t frame) const { return (GetFrame(frame)->ncolours); }
-int wxGIFDecoder::GetTransparentColourIndex(size_t frame) const { return (GetFrame(frame)->transparent); }
+unsigned char* wxGIFDecoder::GetData(unsigned int frame) const { return (GetFrame(frame)->p); }
+unsigned char* wxGIFDecoder::GetPalette(unsigned int frame) const { return (GetFrame(frame)->pal); }
+unsigned int wxGIFDecoder::GetNcolours(unsigned int frame) const { return (GetFrame(frame)->ncolours); }
+int wxGIFDecoder::GetTransparentColourIndex(unsigned int frame) const { return (GetFrame(frame)->transparent); }
//
int wxGIFDecoder::getcode(wxInputStream& stream, int bits, int ab_fin)
{
- unsigned int mask; /* bit mask */
- unsigned int code; /* code (result) */
+ unsigned int mask; // bit mask
+ unsigned int code; // code (result)
- /* get remaining bits from last byte read */
+ // get remaining bits from last byte read
mask = (1 << bits) - 1;
code = (m_lastbyte >> (8 - m_restbits)) & mask;
- /* keep reading new bytes while needed */
+ // keep reading new bytes while needed
while (bits > m_restbits)
{
- /* if no bytes left in this block, read the next block */
+ // if no bytes left in this block, read the next block
if (m_restbyte == 0)
{
m_restbyte = (unsigned char)stream.GetC();
break;
}
- /* prefetch data */
+ // prefetch data
stream.Read((void *) m_buffer, m_restbyte);
if (stream.LastRead() != m_restbyte)
{
m_bufp = m_buffer;
}
- /* read next byte and isolate the bits we need */
+ // read next byte and isolate the bits we need
m_lastbyte = (unsigned char) (*m_bufp++);
mask = (1 << (bits - m_restbits)) - 1;
code = code + ((m_lastbyte & mask) << m_restbits);
m_restbyte--;
- /* adjust total number of bits extracted from the buffer */
+ // adjust total number of bits extracted from the buffer
m_restbits = m_restbits + 8;
}
- /* find number of bits remaining for next code */
+ // find number of bits remaining for next code
m_restbits = (m_restbits - bits);
return code;
// is 'bits'. Supports interlaced images (interl == 1).
// Returns wxGIF_OK (== 0) on success, or an error code if something
// fails (see header file for details)
-wxGIFErrorCode wxGIFDecoder::dgif(wxInputStream& stream, GIFImage *img, int interl, int bits)
+wxGIFErrorCode
+wxGIFDecoder::dgif(wxInputStream& stream, GIFImage *img, int interl, int bits)
{
static const int allocSize = 4096 + 1;
- int *ab_prefix = new int[allocSize]; /* alphabet (prefixes) */
+ int *ab_prefix = new int[allocSize]; // alphabet (prefixes)
if (ab_prefix == NULL)
{
return wxGIF_MEMERR;
}
- int *ab_tail = new int[allocSize]; /* alphabet (tails) */
+ int *ab_tail = new int[allocSize]; // alphabet (tails)
if (ab_tail == NULL)
{
delete[] ab_prefix;
return wxGIF_MEMERR;
}
- int *stack = new int[allocSize]; /* decompression stack */
+ int *stack = new int[allocSize]; // decompression stack
if (stack == NULL)
{
delete[] ab_prefix;
return wxGIF_MEMERR;
}
- int ab_clr; /* clear code */
- int ab_fin; /* end of info code */
- int ab_bits; /* actual symbol width, in bits */
- int ab_free; /* first free position in alphabet */
- int ab_max; /* last possible character in alphabet */
- int pass; /* pass number in interlaced images */
- int pos; /* index into decompresion stack */
- unsigned int x, y; /* position in image buffer */
+ int ab_clr; // clear code
+ int ab_fin; // end of info code
+ int ab_bits; // actual symbol width, in bits
+ int ab_free; // first free position in alphabet
+ int ab_max; // last possible character in alphabet
+ int pass; // pass number in interlaced images
+ int pos; // index into decompresion stack
+ unsigned int x, y; // position in image buffer
int code, readcode, lastcode, abcabca;
- /* these won't change */
+ // these won't change
ab_clr = (1 << bits);
ab_fin = (1 << bits) + 1;
- /* these will change through the decompression proccess */
+ // these will change through the decompression proccess
ab_bits = bits + 1;
ab_free = (1 << bits) + 2;
ab_max = (1 << ab_bits) - 1;
pass = 1;
pos = x = y = 0;
- /* reset decoder vars */
+ // reset decoder vars
m_restbits = 0;
m_restbyte = 0;
m_lastbyte = 0;
do
{
- /* get next code */
+ // get next code
readcode = code = getcode(stream, ab_bits, ab_fin);
- /* end of image? */
+ // end of image?
if (code == ab_fin) break;
- /* reset alphabet? */
+ // reset alphabet?
if (code == ab_clr)
{
- /* reset main variables */
+ // reset main variables
ab_bits = bits + 1;
ab_free = (1 << bits) + 2;
ab_max = (1 << ab_bits) - 1;
lastcode = -1;
abcabca = -1;
- /* skip to next code */
+ // skip to next code
continue;
}
- /* unknown code: special case (like in ABCABCA) */
+ // unknown code: special case (like in ABCABCA)
if (code >= ab_free)
{
- code = lastcode; /* take last string */
- stack[pos++] = abcabca; /* add first character */
+ code = lastcode; // take last string
+ stack[pos++] = abcabca; // add first character
}
- /* build the string for this code in the stack */
+ // build the string for this code in the stack
while (code > ab_clr)
{
stack[pos++] = ab_tail[code];
return wxGIF_INVFORMAT;
}
- stack[pos] = code; /* push last code into the stack */
- abcabca = code; /* save for special case */
+ stack[pos] = code; // push last code into the stack
+ abcabca = code; // save for special case
- /* make new entry in alphabet (only if NOT just cleared) */
+ // make new entry in alphabet (only if NOT just cleared)
if (lastcode != -1)
{
// Normally, after the alphabet is full and can't grow any
}
}
- /* dump stack data to the image buffer */
+ // dump stack data to the image buffer
while (pos >= 0)
{
(img->p)[x + (y * (img->w))] = (char) stack[pos];
if (interl)
{
- /* support for interlaced images */
+ // support for interlaced images
switch (pass)
{
case 1: y += 8; break;
}
else
{
- /* non-interlaced */
+ // non-interlaced
y++;
/*
Normally image decoding is finished when an End of Information code is
if ( !stream.Read(buf, WXSIZEOF(buf)) )
return false;
- stream.SeekI(-(wxFileOffset)WXSIZEOF(buf), wxFromCurrent);
+ if (stream.SeekI(-(wxFileOffset)WXSIZEOF(buf), wxFromCurrent) == wxInvalidOffset)
+ return false; // this happens e.g. for non-seekable streams
return memcmp(buf, "GIF", WXSIZEOF(buf)) == 0;
}
wxGIFErrorCode wxGIFDecoder::LoadGIF(wxInputStream& stream)
{
unsigned int global_ncolors = 0;
- int bits, interl, transparent, i;
+ int bits, interl, i;
wxAnimationDisposal disposal;
long size;
long delay;
unsigned char buf[16];
bool anim = true;
- /* check GIF signature */
+ // check GIF signature
if (!CanRead(stream))
return wxGIF_INVFORMAT;
- /* check for animated GIF support (ver. >= 89a) */
+ // check for animated GIF support (ver. >= 89a)
- static const size_t headerSize = (3 + 3);
+ static const unsigned int headerSize = (3 + 3);
stream.Read(buf, headerSize);
if (stream.LastRead() != headerSize)
{
anim = false;
}
- /* read logical screen descriptor block (LSDB) */
- static const size_t lsdbSize = (2 + 2 + 1 + 1 + 1);
+ // read logical screen descriptor block (LSDB)
+ static const unsigned int lsdbSize = (2 + 2 + 1 + 1 + 1);
stream.Read(buf, lsdbSize);
if (stream.LastRead() != lsdbSize)
{
m_szAnimation.SetWidth( buf[0] + 256 * buf[1] );
m_szAnimation.SetHeight( buf[2] + 256 * buf[3] );
- if ((m_szAnimation.GetWidth() == 0) || (m_szAnimation.GetHeight() == 0))
+ if (anim && ((m_szAnimation.GetWidth() == 0) || (m_szAnimation.GetHeight() == 0)))
{
return wxGIF_INVFORMAT;
}
- /* load global color map if available */
+ // load global color map if available
if ((buf[4] & 0x80) == 0x80)
{
int backgroundColIndex = buf[5];
global_ncolors = 2 << (buf[4] & 0x07);
- size_t numBytes = 3 * global_ncolors;
+ unsigned int numBytes = 3 * global_ncolors;
stream.Read(pal, numBytes);
if (stream.LastRead() != numBytes)
{
pal[backgroundColIndex*3 + 2]);
}
- /* transparent colour, disposal method and delay default to unused */
- transparent = -1;
+ // transparent colour, disposal method and delay default to unused
+ int transparent = -1;
disposal = wxANIM_UNSPECIFIED;
delay = -1;
break; // Alternative : "return wxGIF_INVFORMAT;"
}
- /* end of data? */
+ // end of data?
if (type == 0x3B)
{
done = true;
}
else
- /* extension block? */
+ // extension block?
if (type == 0x21)
{
if (((unsigned char)stream.GetC()) == 0xF9)
- /* graphics control extension, parse it */
+ // graphics control extension, parse it
{
- static const size_t gceSize = 6;
+ static const unsigned int gceSize = 6;
stream.Read(buf, gceSize);
if (stream.LastRead() != gceSize)
{
return wxGIF_INVFORMAT;
}
- /* read delay and convert from 1/100 of a second to ms */
+ // read delay and convert from 1/100 of a second to ms
delay = 10 * (buf[2] + 256 * buf[3]);
- /* read transparent colour index, if used */
- if (buf[1] & 0x01)
- transparent = buf[4];
+ // read transparent colour index, if used
+ transparent = buf[1] & 0x01 ? buf[4] : -1;
- /* read disposal method */
+ // read disposal method
disposal = (wxAnimationDisposal)(((buf[1] & 0x1C) >> 2) - 1);
}
else
- /* other extension, skip */
+ // other extension, skip
{
while ((i = (unsigned char)stream.GetC()) != 0)
{
- if (stream.Eof() || (stream.LastRead() == 0))
+ if (stream.Eof() || (stream.LastRead() == 0) ||
+ stream.SeekI(i, wxFromCurrent) == wxInvalidOffset)
{
done = true;
break;
}
- stream.SeekI(i, wxFromCurrent);
}
}
}
else
- /* image descriptor block? */
+ // image descriptor block?
if (type == 0x2C)
{
- /* allocate memory for IMAGEN struct */
- GIFImage *pimg = new GIFImage();
+ // allocate memory for IMAGEN struct
+ GIFImagePtr pimg(new GIFImage());
- if (pimg == NULL)
- {
- Destroy();
+ wxScopeGuard guardDestroy = wxMakeObjGuard(*this, &wxGIFDecoder::Destroy);
+
+ if ( !pimg.get() )
return wxGIF_MEMERR;
- }
- /* fill in the data */
- static const size_t idbSize = (2 + 2 + 2 + 2 + 1);
+ // fill in the data
+ static const unsigned int idbSize = (2 + 2 + 2 + 2 + 1);
stream.Read(buf, idbSize);
if (stream.LastRead() != idbSize)
- {
- Destroy();
return wxGIF_INVFORMAT;
- }
pimg->left = buf[0] + 256 * buf[1];
pimg->top = buf[2] + 256 * buf[3];
pimg->w = buf[4] + 256 * buf[5];
pimg->h = buf[6] + 256 * buf[7];
- if ((pimg->w == 0) || (pimg->w > (unsigned int)m_szAnimation.GetWidth()) ||
- (pimg->h == 0) || (pimg->h > (unsigned int)m_szAnimation.GetHeight()))
- {
- Destroy();
+ if ( anim && ((pimg->w == 0) || (pimg->w > (unsigned int)m_szAnimation.GetWidth()) ||
+ (pimg->h == 0) || (pimg->h > (unsigned int)m_szAnimation.GetHeight())) )
return wxGIF_INVFORMAT;
- }
interl = ((buf[8] & 0x40)? 1 : 0);
size = pimg->w * pimg->h;
pimg->disposal = disposal;
pimg->delay = delay;
- /* allocate memory for image and palette */
- pimg->p = (unsigned char *) malloc((size_t)size);
+ // allocate memory for image and palette
+ pimg->p = (unsigned char *) malloc((unsigned int)size);
pimg->pal = (unsigned char *) malloc(768);
if ((!pimg->p) || (!pimg->pal))
- {
- Destroy();
return wxGIF_MEMERR;
- }
- /* load local color map if available, else use global map */
+ // load local color map if available, else use global map
if ((buf[8] & 0x80) == 0x80)
{
unsigned int local_ncolors = 2 << (buf[8] & 0x07);
- size_t numBytes = 3 * local_ncolors;
+ unsigned int numBytes = 3 * local_ncolors;
stream.Read(pimg->pal, numBytes);
pimg->ncolours = local_ncolors;
if (stream.LastRead() != numBytes)
- {
- Destroy();
return wxGIF_INVFORMAT;
- }
}
else
{
pimg->ncolours = global_ncolors;
}
- /* get initial code size from first byte in raster data */
+ // get initial code size from first byte in raster data
bits = (unsigned char)stream.GetC();
if (bits == 0)
- {
- Destroy();
return wxGIF_INVFORMAT;
- }
- /* decode image */
- wxGIFErrorCode result = dgif(stream, pimg, interl, bits);
+ // decode image
+ wxGIFErrorCode result = dgif(stream, pimg.get(), interl, bits);
if (result != wxGIF_OK)
- {
- Destroy();
return result;
- }
- /* add the image to our frame array */
- m_frames.Add((void*)pimg);
+ guardDestroy.Dismiss();
+
+ // add the image to our frame array
+ m_frames.Add(pimg.release());
m_nFrames++;
- /* if this is not an animated GIF, exit after first image */
+ // if this is not an animated GIF, exit after first image
if (!anim)
done = true;
}
return wxGIF_INVFORMAT;
}
- /* try to read to the end of the stream */
+ // try to read to the end of the stream
while (type != 0x3B)
{
if (!stream.IsOk())
if (type == 0x21)
{
- /* extension type */
+ // extension type
(void) stream.GetC();
- /* skip all data */
+ // skip all data
while ((i = (unsigned char)stream.GetC()) != 0)
{
- if (stream.Eof() || (stream.LastRead() == 0))
+ if (stream.Eof() || (stream.LastRead() == 0) ||
+ stream.SeekI(i, wxFromCurrent) == wxInvalidOffset)
{
Destroy();
return wxGIF_INVFORMAT;
}
- stream.SeekI(i, wxFromCurrent);
}
}
else if (type == 0x2C)
{
- /* image descriptor block */
- static const size_t idbSize = (2 + 2 + 2 + 2 + 1);
+ // image descriptor block
+ static const unsigned int idbSize = (2 + 2 + 2 + 2 + 1);
stream.Read(buf, idbSize);
if (stream.LastRead() != idbSize)
{
return wxGIF_INVFORMAT;
}
- /* local color map */
+ // local color map
if ((buf[8] & 0x80) == 0x80)
{
unsigned int local_ncolors = 2 << (buf[8] & 0x07);
wxFileOffset numBytes = 3 * local_ncolors;
- stream.SeekI(numBytes, wxFromCurrent);
+ if (stream.SeekI(numBytes, wxFromCurrent) == wxInvalidOffset)
+ {
+ Destroy();
+ return wxGIF_INVFORMAT;
+ }
}
- /* initial code size */
+ // initial code size
(void) stream.GetC();
if (stream.Eof() || (stream.LastRead() == 0))
{
return wxGIF_INVFORMAT;
}
- /* skip all data */
+ // skip all data
while ((i = (unsigned char)stream.GetC()) != 0)
{
- if (stream.Eof() || (stream.LastRead() == 0))
+ if (stream.Eof() || (stream.LastRead() == 0) ||
+ stream.SeekI(i, wxFromCurrent) == wxInvalidOffset)
{
Destroy();
return wxGIF_INVFORMAT;
}
- stream.SeekI(i, wxFromCurrent);
}
}
- else if ((type != 0x3B) && (type != 00)) /* testing */
+ else if ((type != 0x3B) && (type != 00)) // testing
{
- /* images are OK, but couldn't read to the end of the stream */
+ // images are OK, but couldn't read to the end of the stream
return wxGIF_TRUNCATED;
}
}
projects / wxWidgets.git / blobdiff