Backed-out PNG8 patch (no time to look at why

[wxWidgets.git] / src / tiff / tif_tile.c

diff --git a/src/tiff/tif_tile.c b/src/tiff/tif_tile.c
index 931b6872bb69f0bd2d7822b358ba6195332ea6fd..5a0b433a20db66656be236d1f2edd85ab17366b1 100644 (file)
--- a/src/tiff/tif_tile.c
+++ b/src/tiff/tif_tile.c
@@ -31,6 +31,32 @@
  */
 #include "tiffiop.h"
 
+static uint32
+summarize(TIFF* tif, size_t summand1, size_t summand2, const char* where)
+{
+       uint32  bytes = summand1 + summand2;
+
+       if (bytes - summand1 != summand2) {
+               TIFFError(tif->tif_name, "Integer overflow in %s", where);
+               bytes = 0;
+       }
+
+       return (bytes);
+}
+
+static uint32
+multiply(TIFF* tif, size_t nmemb, size_t elem_size, const char* where)
+{
+       uint32  bytes = nmemb * elem_size;
+
+       if (elem_size && bytes / elem_size != nmemb) {
+               TIFFError(tif->tif_name, "Integer overflow in %s", where);
+               bytes = 0;
+       }
+
+       return (bytes);
+}
+
 /*
  * Compute which tile an (x,y,z,s) value is in.
  */
@@ -62,7 +88,7 @@ TIFFComputeTile(TIFF* tif, uint32 x, uint32 y, uint32 z, tsample_t s)
                             xpt*(y/dy) +
                             x/dx;
                else
-                       tile = (xpt*ypt)*(z/dz) + xpt*(y/dy) + x/dx + s;
+                       tile = (xpt*ypt)*(z/dz) + xpt*(y/dy) + x/dx;
        }
        return (tile);
 }
@@ -119,11 +145,13 @@ TIFFNumberOfTiles(TIFF* tif)
        if (dz == (uint32) -1)
                dz = td->td_imagedepth;
        ntiles = (dx == 0 || dy == 0 || dz == 0) ? 0 :
-           (TIFFhowmany(td->td_imagewidth, dx) *
-            TIFFhowmany(td->td_imagelength, dy) *
-            TIFFhowmany(td->td_imagedepth, dz));
+           multiply(tif, multiply(tif, TIFFhowmany(td->td_imagewidth, dx),
+                                  TIFFhowmany(td->td_imagelength, dy),
+                                  "TIFFNumberOfTiles"),
+                    TIFFhowmany(td->td_imagedepth, dz), "TIFFNumberOfTiles");
        if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
-               ntiles *= td->td_samplesperpixel;
+               ntiles = multiply(tif, ntiles, td->td_samplesperpixel,
+                                 "TIFFNumberOfTiles");
        return (ntiles);
 }
 
@@ -138,10 +166,12 @@ TIFFTileRowSize(TIFF* tif)
        
        if (td->td_tilelength == 0 || td->td_tilewidth == 0)
                return ((tsize_t) 0);
-       rowsize = td->td_bitspersample * td->td_tilewidth;
+       rowsize = multiply(tif, td->td_bitspersample, td->td_tilewidth,
+                          "TIFFTileRowSize");
        if (td->td_planarconfig == PLANARCONFIG_CONTIG)
-               rowsize *= td->td_samplesperpixel;
-       return ((tsize_t) TIFFhowmany(rowsize, 8));
+               rowsize = multiply(tif, rowsize, td->td_samplesperpixel,
+                                  "TIFFTileRowSize");
+       return ((tsize_t) TIFFhowmany8(rowsize));
 }
 
 /*
@@ -170,16 +200,24 @@ TIFFVTileSize(TIFF* tif, uint32 nrows)
                 */
                tsize_t w =
                    TIFFroundup(td->td_tilewidth, td->td_ycbcrsubsampling[0]);
-               tsize_t rowsize = TIFFhowmany(w*td->td_bitspersample, 8);
+               tsize_t rowsize =
+                   TIFFhowmany8(multiply(tif, w, td->td_bitspersample,
+                                         "TIFFVTileSize"));
                tsize_t samplingarea =
                    td->td_ycbcrsubsampling[0]*td->td_ycbcrsubsampling[1];
                nrows = TIFFroundup(nrows, td->td_ycbcrsubsampling[1]);
                /* NB: don't need TIFFhowmany here 'cuz everything is rounded */
-               tilesize = nrows*rowsize + 2*(nrows*rowsize / samplingarea);
+               tilesize = multiply(tif, nrows, rowsize, "TIFFVTileSize");
+               tilesize = summarize(tif, tilesize,
+                                    multiply(tif, 2, tilesize / samplingarea,
+                                             "TIFFVTileSize"),
+                                    "TIFFVTileSize");
        } else
 #endif
-               tilesize = nrows * TIFFTileRowSize(tif);
-       return ((tsize_t)(tilesize * td->td_tiledepth));
+               tilesize = multiply(tif, nrows, TIFFTileRowSize(tif),
+                                   "TIFFVTileSize");
+       return ((tsize_t)
+           multiply(tif, tilesize, td->td_tiledepth, "TIFFVTileSize"));
 }
 
 /*