wxImage::Ok() now returns false for images with 0 width or height

[wxWidgets.git] / src / common / gifdecod.cpp

diff --git a/src/common/gifdecod.cpp b/src/common/gifdecod.cpp
index 32a89223c3838334d6f7f72272d0fa535999bded..c08bf1fdf62a7f4810aff262100a143647ca4277 100644 (file)
--- a/src/common/gifdecod.cpp
+++ b/src/common/gifdecod.cpp
@@ -2,8 +2,8 @@
 // Name:        gifdecod.cpp
 // Purpose:     wxGIFDecoder, GIF reader for wxImage and wxAnimation
 // Author:      Guillermo Rodriguez Garcia <guille@iies.es>
 // Name:        gifdecod.cpp
 // Purpose:     wxGIFDecoder, GIF reader for wxImage and wxAnimation
 // Author:      Guillermo Rodriguez Garcia <guille@iies.es>

-// Version:     3.02
-// Last rev:    1999/08/18
+// Version:     3.04
+// RCS-ID:      $Id$

 // Copyright:   (c) Guillermo Rodriguez Garcia
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 // Copyright:   (c) Guillermo Rodriguez Garcia
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////


@@ -20,16 +20,15 @@
 #endif
 
 #ifndef WX_PRECOMP
 #endif
 
 #ifndef WX_PRECOMP

-#  include "wx/setup.h"
+#  include "wx/defs.h"

 #endif
 
 #endif
 

-#if wxUSE_STREAMS
+#if wxUSE_STREAMS && wxUSE_GIF

 
 #include <stdlib.h>
 #include <string.h>
 
 #include <stdlib.h>
 #include <string.h>

-#include "wx/defs.h"

 #include "wx/gifdecod.h"
 #include "wx/gifdecod.h"

- 
+

 
 //---------------------------------------------------------------------------
 // wxGIFDecoder constructor and destructor
 
 //---------------------------------------------------------------------------
 // wxGIFDecoder constructor and destructor


@@ -37,7 +36,7 @@
 
 wxGIFDecoder::wxGIFDecoder(wxInputStream *s, bool anim)
 {
 
 wxGIFDecoder::wxGIFDecoder(wxInputStream *s, bool anim)
 {

-    m_f = s;
+    m_f    = s;

     m_anim = anim;
 
     m_background = -1;
     m_anim = anim;
 
     m_background = -1;


@@ -58,7 +57,7 @@ wxGIFDecoder::~wxGIFDecoder()
 
 void wxGIFDecoder::Destroy()
 {
 
 void wxGIFDecoder::Destroy()
 {

-    IMAGEN *pimg, *paux;
+    GIFImage *pimg, *paux;

 
     pimg = m_pfirst;
 
 
     pimg = m_pfirst;
 


@@ -67,9 +66,15 @@ void wxGIFDecoder::Destroy()
         paux = pimg->next;
         free(pimg->p);
         free(pimg->pal);
         paux = pimg->next;
         free(pimg->p);
         free(pimg->pal);

-        free(pimg);
+        delete pimg;

         pimg = paux;
     }
         pimg = paux;
     }

+
+    m_pimage  = NULL;
+    m_pfirst  = NULL;
+    m_plast   = NULL;
+    m_image   = 0;
+    m_nimages = 0;

 }
 
 
 }
 
 


@@ -121,6 +126,25 @@ bool wxGIFDecoder::ConvertToImage(wxImage *image) const
     else
         image->SetMask(FALSE);
 
     else
         image->SetMask(FALSE);
 

+    // Set the palette
+    // Palette creation not yet implemented on wxGTK
+#ifndef __WXGTK__
+    if (pal)
+    {
+        unsigned char* r = new unsigned char[256];
+        unsigned char* g = new unsigned char[256];
+        unsigned char* b = new unsigned char[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];
+        }
+        image->SetPalette(wxPalette(256, r, g, b));
+        delete[] r; delete[] g; delete[] b;
+    }
+#endif
+

     /* copy image data */
     for (i = 0; i < (GetWidth() * GetHeight()); i++, src++)
     {
     /* copy image data */
     for (i = 0; i < (GetWidth() * GetHeight()); i++, src++)
     {


@@ -132,7 +156,7 @@ bool wxGIFDecoder::ConvertToImage(wxImage *image) const
     return TRUE;
 }
 
     return TRUE;
 }
 

-                 
+

 //---------------------------------------------------------------------------
 // Data accessors
 //---------------------------------------------------------------------------
 //---------------------------------------------------------------------------
 // Data accessors
 //---------------------------------------------------------------------------


@@ -203,7 +227,7 @@ bool wxGIFDecoder::GoNextFrame(bool cyclic)
     }
     else
         return FALSE;
     }
     else
         return FALSE;

-}            
+}

 
 bool wxGIFDecoder::GoPrevFrame(bool cyclic)
 {
 
 bool wxGIFDecoder::GoPrevFrame(bool cyclic)
 {


@@ -283,10 +307,14 @@ int wxGIFDecoder::getcode(int bits, int ab_fin)
                 code = ab_fin;
                 break;
             }
                 code = ab_fin;
                 break;
             }

+
+            /* prefetch data */
+            m_f->Read((void *) m_buffer, 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_f->GetC();
+        m_lastbyte = (unsigned char) (*m_bufp++);

         mask       = (1 << (bits - m_restbits)) - 1;
         code       = code + ((m_lastbyte & mask) << m_restbits);
         m_restbyte--;
         mask       = (1 << (bits - m_restbits)) - 1;
         code       = code + ((m_lastbyte & mask) << m_restbits);
         m_restbyte--;


@@ -294,7 +322,7 @@ int wxGIFDecoder::getcode(int bits, int ab_fin)
         /* adjust total number of bits extracted from the buffer */
         m_restbits = m_restbits + 8;
     }
         /* adjust total number of bits extracted from the buffer */
         m_restbits = m_restbits + 8;
     }

-    
+

     /* find number of bits remaining for next code */
     m_restbits = (m_restbits - bits);
 
     /* find number of bits remaining for next code */
     m_restbits = (m_restbits - bits);
 


@@ -306,12 +334,17 @@ int wxGIFDecoder::getcode(int bits, int ab_fin)
 //  GIF decoding function. The initial code size (aka root size)
 //  is 'bits'. Supports interlaced images (interl == 1).
 //
 //  GIF decoding function. The initial code size (aka root size)
 //  is 'bits'. Supports interlaced images (interl == 1).
 //

-int wxGIFDecoder::dgif(IMAGEN *img, int interl, int bits)
+int wxGIFDecoder::dgif(GIFImage *img, int interl, int bits)

 {
 {

+#ifdef __WXMAC__
+    int *ab_prefix = new int[4096];        /* alphabet (prefixes) */
+    int *ab_tail = new int[4096];          /* alphabet (tails) */
+    int *stack = new int[4096];            /* decompression stack */
+#else

     int ab_prefix[4096];        /* alphabet (prefixes) */
     int ab_tail[4096];          /* alphabet (tails) */
     int stack[4096];            /* decompression stack */
     int ab_prefix[4096];        /* alphabet (prefixes) */
     int ab_tail[4096];          /* alphabet (tails) */
     int stack[4096];            /* decompression stack */

-
+#endif

     int ab_clr;                 /* clear code */
     int ab_fin;                 /* end of info code */
     int ab_bits;                /* actual symbol width, in bits */
     int ab_clr;                 /* clear code */
     int ab_fin;                 /* end of info code */
     int ab_bits;                /* actual symbol width, in bits */


@@ -336,7 +369,7 @@ int wxGIFDecoder::dgif(IMAGEN *img, int interl, int bits)
     pass     = 1;
     pos = x = y = 0;
 
     pass     = 1;
     pos = x = y = 0;
 

-    /* reset static globals */
+    /* reset decoder vars */

     m_restbits = 0;
     m_restbyte = 0;
     m_lastbyte = 0;
     m_restbits = 0;
     m_restbyte = 0;
     m_lastbyte = 0;


@@ -435,6 +468,11 @@ int wxGIFDecoder::dgif(IMAGEN *img, int interl, int bits)
     }
     while (code != ab_fin);
 
     }
     while (code != ab_fin);
 

+#ifdef __WXMAC__
+    delete [] ab_prefix ;       
+    delete [] ab_tail ;       
+    delete [] stack ;       
+#endif

     return 0;
 }
 
     return 0;
 }
 


@@ -446,8 +484,8 @@ bool wxGIFDecoder::CanRead()
 {
     unsigned char buf[3];
 
 {
     unsigned char buf[3];
 

-    m_f->SeekI(0, wxFromStart);

     m_f->Read(buf, 3);
     m_f->Read(buf, 3);

+    m_f->SeekI(-3, wxFromCurrent);

 
     return (memcmp(buf, "GIF", 3) == 0);
 }
 
     return (memcmp(buf, "GIF", 3) == 0);
 }


@@ -458,26 +496,25 @@ bool wxGIFDecoder::CanRead()
 //  animated GIF support is enabled. Can read GIFs with any bit
 //  size (color depth), but the output images are always expanded
 //  to 8 bits per pixel. Also, the image palettes always contain
 //  animated GIF support is enabled. Can read GIFs with any bit
 //  size (color depth), but the output images are always expanded
 //  to 8 bits per pixel. Also, the image palettes always contain

-//  256 colors, although some of them may be unused. Returns E_OK
-//  (== 0) on success, or an error code if something fails. Error
-//  codes are E_ARCHIVO, E_FORMATO, E_MEMORIA (see header file).
+//  256 colors, although some of them may be unused. Returns wxGIF_OK
+//  (== 0) on success, or an error code if something fails (see
+//  header file for details)

 //
 int wxGIFDecoder::ReadGIF()
 {
     int           ncolors, bits, interl, transparent, disposal, i;
     long          size;
     long          delay;
 //
 int wxGIFDecoder::ReadGIF()
 {
     int           ncolors, bits, interl, transparent, disposal, i;
     long          size;
     long          delay;

-    unsigned char type;
+    unsigned char type = 0;

     unsigned char pal[768];
     unsigned char buf[16];
     unsigned char pal[768];
     unsigned char buf[16];

-    IMAGEN        **ppimg, *pimg, *pprev;
+    GIFImage      **ppimg, *pimg, *pprev;

 
     /* check GIF signature */
     if (!CanRead())
 
     /* check GIF signature */
     if (!CanRead())

-        return E_FORMATO;
+        return wxGIF_INVFORMAT;

 
 

-    /* check for and animated GIF support (ver. >= 89a) */
-    m_f->SeekI(0, wxFromStart);
+    /* check for animated GIF support (ver. >= 89a) */

     m_f->Read(buf, 6);
 
     if (memcmp(buf + 3, "89a", 3) < 0)
     m_f->Read(buf, 6);
 
     if (memcmp(buf + 3, "89a", 3) < 0)


@@ -507,14 +544,18 @@ int wxGIFDecoder::ReadGIF()
     pprev = NULL;
     pimg  = NULL;
 
     pprev = NULL;
     pimg  = NULL;
 

-    while (1)
+    bool done = FALSE;
+
+    while(!done)

     {
         type = (unsigned char)m_f->GetC();
 
         /* end of data? */
         if (type == 0x3B)
     {
         type = (unsigned char)m_f->GetC();
 
         /* end of data? */
         if (type == 0x3B)

-            break;
-
+        {
+            done = TRUE;
+        }
+        else

         /* extension block? */
         if (type == 0x21)
         {
         /* extension block? */
         if (type == 0x21)
         {


@@ -535,29 +576,24 @@ int wxGIFDecoder::ReadGIF()
             }
             else
             /* other extension, skip */
             }
             else
             /* other extension, skip */

-            {   
+            {

                 while ((i = (unsigned char)m_f->GetC()) != 0)
                 {
                 while ((i = (unsigned char)m_f->GetC()) != 0)
                 {

-                    /* This line should not be neccessary!
-                     * Some images are not loaded correctly
-                     * without it. A bug in wxStream?
-                     */
-                    // m_f->SeekI(m_f->TellI(), wxFromStart);

                     m_f->SeekI(i, wxFromCurrent);
                 }
             }
         }
                     m_f->SeekI(i, wxFromCurrent);
                 }
             }
         }

-
+        else

         /* image descriptor block? */
         if (type == 0x2C)
         {
             /* allocate memory for IMAGEN struct */
         /* image descriptor block? */
         if (type == 0x2C)
         {
             /* allocate memory for IMAGEN struct */

-            pimg = (*ppimg) = (IMAGEN *) malloc(sizeof(IMAGEN));
+            pimg = (*ppimg) = new GIFImage();

 
             if (pimg == NULL)
             {
                 Destroy();
 
             if (pimg == NULL)
             {
                 Destroy();

-                return E_MEMORIA;
+                return wxGIF_MEMERR;

             }
 
             /* fill in the data */
             }
 
             /* fill in the data */


@@ -578,13 +614,13 @@ int wxGIFDecoder::ReadGIF()
             ppimg = &pimg->next;
 
             /* allocate memory for image and palette */
             ppimg = &pimg->next;
 
             /* allocate memory for image and palette */

-            pimg->p   = (unsigned char *) malloc(size);
+            pimg->p   = (unsigned char *) malloc((size_t)size);

             pimg->pal = (unsigned char *) malloc(768);
 
             if ((!pimg->p) || (!pimg->pal))
             {
                 Destroy();
             pimg->pal = (unsigned char *) malloc(768);
 
             if ((!pimg->p) || (!pimg->pal))
             {
                 Destroy();

-                return E_MEMORIA;
+                return wxGIF_MEMERR;

             }
 
             /* load local color map if available, else use global map */
             }
 
             /* load local color map if available, else use global map */


@@ -601,16 +637,15 @@ int wxGIFDecoder::ReadGIF()
 
             /* decode image */
             dgif(pimg, interl, bits);
 
             /* decode image */
             dgif(pimg, interl, bits);

-

             m_nimages++;
             m_nimages++;

-        }

 
 

-        /* if we have one image and no animated GIF support, exit */
-        if (m_nimages == 1 && !m_anim)
-            break;
+            /* if this is not an animated GIF, exit after first image */
+            if (!m_anim)
+                done = TRUE;
+        }

     }
 
     }
 

-    /* finish successfully :-) */
+    /* setup image pointers */

     if (m_nimages != 0)
     {
         m_image = 1;
     if (m_nimages != 0)
     {
         m_image = 1;


@@ -618,7 +653,51 @@ int wxGIFDecoder::ReadGIF()
         m_pimage = m_pfirst;
     }
 
         m_pimage = m_pfirst;
     }
 

-    return E_OK;
+    /* try to read to the end of the stream */
+    while (type != 0x3B)
+    {
+        type = (unsigned char)m_f->GetC();
+
+        if (type == 0x21)
+        {
+            /* extension type */
+            (void) m_f->GetC();
+
+            /* skip all data */
+            while ((i = (unsigned char)m_f->GetC()) != 0)
+            {
+                m_f->SeekI(i, wxFromCurrent);
+            }
+        }
+        else if (type == 0x2C)
+        {
+            /* image descriptor block */
+            m_f->Read(buf, 9);
+
+            /* local color map */
+            if ((buf[8] & 0x80) == 0x80)
+            {
+                ncolors = 2 << (buf[8] & 0x07);
+                m_f->SeekI(3 * ncolors, wxFromCurrent);
+            }
+
+            /* initial code size */
+            (void) m_f->GetC();
+
+            /* skip all data */
+            while ((i = (unsigned char)m_f->GetC()) != 0)
+            {
+                m_f->SeekI(i, wxFromCurrent);
+            }
+        }
+        else if ((type != 0x3B) && (type != 00)) /* testing */
+        {
+            /* images are OK, but couldn't read to the end of the stream */
+            return wxGIF_TRUNCATED;
+        }
+    }
+
+    return wxGIF_OK;

 }
 
 }
 

-#endif // wxUSE_STREAM
+#endif // wxUSE_STREAMS && wxUSE_GIF