Revert "[libpng16] Quieted about 100 warnings from clang-3.8 in pngtrans.c, pngread.c,"

This reverts commit 97dfccb6325e54d45c4440b6dd037619d88688cc.

ANNOUNCE

@@ -1,4 +1,4 @@
-Libpng 1.6.26beta02 - October 1, 2016
+Libpng 1.6.26beta02 - September 30, 2016
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -41,10 +41,9 @@ Version 1.6.26beta01 [September 26, 2016]
   Add tests/badcrc.png and tests/badadler.png to tests/pngtest.
   Merged pngtest.c with libpng-1.7.0beta84/pngtest.c
 
-Version 1.6.26beta02 [October 1, 2016]
+Version 1.6.26beta02 [September 30, 2016]
   Updated the documentation about CRC and ADLER32 handling.
-  Quieted about 100 warnings from clang-3.8 in pngtrans.c, pngread.c,
+  Quieted a warning from clang-3.8 in pngtrans.c.
-     pngwrite.c, pngunknown.c, and pngvalid.c.
   Quieted 116 (out of 288) -Wconversion compiler warnings by changing
     flag definitions in pngpriv.h from 0xnnnn to 0xnnnnU and trivial changes
     in png.c, pngread.c, and pngwutil.c.

CHANGES

@@ -5719,10 +5719,9 @@ Version 1.6.26beta01 [September 26, 2016]
   Add tests/badcrc.png and tests/badadler.png to tests/pngtest.
   Merged pngtest.c with libpng-1.7.0beta84/pngtest.c
 
-Version 1.6.26beta02 [October 1, 2016]
+Version 1.6.26beta02 [September 30, 2016]
   Updated the documentation about CRC and ADLER32 handling.
-  Quieted about 100 warnings from clang-3.8 in pngtrans.c, pngread.c,
+  Quieted a warning from clang-3.8 in pngtrans.c.
-     pngwrite.c, pngunknown.c, and pngvalid.c.
   Quieted 116 (out of 288) -Wconversion compiler warnings by changing
     flag definitions in pngpriv.h from 0xnnnn to 0xnnnnU and trivial changes
     in png.c, pngread.c, and pngwutil.c.

contrib/libtests/pngunknown.c

@@ -476,9 +476,9 @@ get_valid(display *d, png_infop info_ptr)
    /* Map the text chunks back into the flags */
    {
       png_textp text;
-      png_uint_32 ntext = png_get_text(d->png_ptr, info_ptr, &text, NULL) + 1;
+      png_uint_32 ntext = png_get_text(d->png_ptr, info_ptr, &text, NULL);
 
-      while (ntext-- > 1) switch (text[ntext - 1].compression)
+      while (ntext-- > 0) switch (text[ntext].compression)
       {
          case -1:
             flags |= PNG_INFO_tEXt;
@@ -492,7 +492,7 @@ get_valid(display *d, png_infop info_ptr)
             break;
          default:
             fprintf(stderr, "%s(%s): unknown text compression %d\n", d->file,
-               d->test, text[ntext - 1].compression);
+               d->test, text[ntext].compression);
             display_exit(d);
       }
    }

contrib/libtests/pngvalid.c

@@ -1236,13 +1236,13 @@ store_image_check(const png_store* ps, png_const_structp pp, int iImage)
    else
    {
       png_size_t cbRow = ps->cb_row;
-      png_uint_32 rows = ps->image_h + 1;
+      png_uint_32 rows = ps->image_h;
 
       image += iImage * (cbRow+5) * ps->image_h;
 
       image += 2; /* skip image first row markers */
 
-      while (rows-- > 1)
+      while (rows-- > 0)
       {
          if (image[-2] != 190 || image[-1] != 239)
             png_error(pp, "row start overwritten");
@@ -11382,7 +11382,6 @@ perform_interlace_macro_validation(void)
 
    for (pass=0; pass<7; ++pass)
    {
-      /* TO DO: Check this: asan says png_uint_32 is not large enough */
       png_uint_32 m, f, v;
 
       m = PNG_PASS_START_ROW(pass);

pngread.c

@@ -3228,10 +3228,10 @@ png_image_read_colormapped(png_voidp argument)
 
       while (--passes >= 0)
       {
-         png_uint_32      y = image->height + 1;
+         png_uint_32      y = image->height;
          png_bytep        row = png_voidcast(png_bytep, display->first_row);
 
-         while (y-- > 1)
+         while (y-- > 0)
          {
             png_read_row(png_ptr, row, NULL);
             row += row_bytes;
@@ -4061,10 +4061,10 @@ png_image_read_direct(png_voidp argument)
 
       while (--passes >= 0)
       {
-         png_uint_32      y = image->height + 1;
+         png_uint_32      y = image->height;
          png_bytep        row = png_voidcast(png_bytep, display->first_row);
 
-         while (y-- > 1)
+         while (y-- > 0)
          {
             png_read_row(png_ptr, row, NULL);
             row += row_bytes;

pngwrite.c

@@ -1527,7 +1527,7 @@ png_write_image_16bit(png_voidp argument)
    png_uint_16p row_end;
    const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? 3 : 1;
    int aindex = 0;
-   png_uint_32 y = image->height + 1;
+   png_uint_32 y = image->height;
 
    if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
    {
@@ -1554,7 +1554,7 @@ png_write_image_16bit(png_voidp argument)
     */
    row_end = output_row + image->width * (channels+1);
 
-   while (y-- > 1)
+   while (y-- > 0)
    {
       png_const_uint_16p in_ptr = input_row;
       png_uint_16p out_ptr = output_row;
@@ -1682,7 +1682,7 @@ png_write_image_8bit(png_voidp argument)
    png_const_uint_16p input_row = png_voidcast(png_const_uint_16p,
        display->first_row);
    png_bytep output_row = png_voidcast(png_bytep, display->local_row);
-   png_uint_32 y = image->height + 1;
+   png_uint_32 y = image->height;
    const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? 3 : 1;
 
    if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
@@ -1705,7 +1705,7 @@ png_write_image_8bit(png_voidp argument)
       /* Use row_end in place of a loop counter: */
       row_end = output_row + image->width * (channels+1);
 
-      while (y-- > 1)
+      while (y-- > 0)
       {
          png_const_uint_16p in_ptr = input_row;
          png_bytep out_ptr = output_row;
@@ -1746,7 +1746,7 @@ png_write_image_8bit(png_voidp argument)
        */
       png_bytep row_end = output_row + image->width * channels;
 
-      while (y-- > 1)
+      while (y-- > 0)
       {
          png_const_uint_16p in_ptr = input_row;
          png_bytep out_ptr = output_row;
@@ -2134,9 +2134,9 @@ png_image_write_main(png_voidp argument)
    {
       png_const_bytep row = png_voidcast(png_const_bytep, display->first_row);
       ptrdiff_t row_bytes = display->row_bytes;
-      png_uint_32 y = image->height + 1;
+      png_uint_32 y = image->height;
 
-      while (y-- > 1)
+      while (y-- > 0)
       {
          png_write_row(png_ptr, row);
          row += row_bytes;