[libpng16] Added an option to force maximum window size for inflating.

For inflate, reverted previous fixes.
Added fixitxt and pngdeflate to the built programs and removed warnings
from the source code and timepng that are revealed as a result.  Fixed
fixitxt when the chunk length is more than 65535 (untested, no test case).

contrib/tools/fixitxt.c

@@ -24,18 +24,20 @@
  *
  *     gcc -O -o fixitxt fixitxt.c -lz
  */
+#include <zlib.h>
 
 #define MAX_LENGTH 500000
 
-#define GETBREAK c=getchar(); if (c == EOF) break;
-#include <zlib.h>
+#define GETBREAK ((unsigned char)(inchar=getchar())); if (inchar == EOF) break
 
-main()
+int
+main(void)
 {
    unsigned int i;
    unsigned char buf[MAX_LENGTH];
    unsigned long crc;
-   unsigned int c;
+   unsigned char c;
+   int inchar;
 
 /* Skip 8-byte signature */
    for (i=8; i; i--)
@@ -44,17 +46,16 @@ main()
       putchar(c);
    }
 
-if (c != EOF)
+if (inchar != EOF)
 for (;;)
  {
    /* Read the length */
-   unsigned long length;
-   c=GETBREAK; buf[0] = c;
-   c=GETBREAK; buf[1] = c;
-   c=GETBREAK; buf[2] = c;
-   c=GETBREAK; buf[3] = c;
+   unsigned long length; /* must be 32 bits! */
+   c=GETBREAK; buf[0] = c; length  = c; length <<= 8;
+   c=GETBREAK; buf[1] = c; length += c; length <<= 8;
+   c=GETBREAK; buf[2] = c; length += c; length <<= 8;
+   c=GETBREAK; buf[3] = c; length += c;
 
-   length=((((unsigned long) buf[0]<<8 + buf[1]<<16) + buf[2] << 8) + buf[3]);
    /* Read the chunkname */
    c=GETBREAK; buf[4] = c;
    c=GETBREAK; buf[5] = c;
@@ -125,7 +126,7 @@ for (;;)
          putchar(c);
       }
 
-      if (c == EOF)
+      if (inchar == EOF)
       {
          break;
       }
@@ -135,10 +136,12 @@ for (;;)
          break;
    }
 
-   if (c == EOF)
+   if (inchar == EOF)
       break;
 
    if (buf[4] == 73 && buf[5] == 69 && buf[6] == 78 && buf[7] == 68)
      break;
  }
+
+ return 0;
 }