Update zopfli to current google state.

git clone https://code.google.com/p/zopfli/

Files not needed in the pigz distribution were removed.

zopfli/CONTRIBUTORS

@@ -1,5 +1,6 @@
 Mark Adler
 Jyrki Alakuijala
+Frédéric Kayser
 Daniel Reed
 Huzaifa Sidhpurwala
 Péter Szabó

zopfli/README

@@ -1,24 +1,32 @@
 Zopfli Compression Algorithm is a compression library programmed in C to perform
 very good, but slow, deflate or zlib compression.
 
-zopfli.c is separate from the library and contains an example program to create
-very well compressed gzip files.
+The basic function to compress data is ZopfliCompress in zopfli.h. Use the
+ZopfliOptions object to set parameters that affect the speed and compression.
+Use the ZopfliInitOptions function to place the default values in the
+ZopfliOptions first.
 
-The basic functions to compress data are ZopfliDeflate in deflate.h,
-ZopfliZlibCompress in zlib_container.h and ZopfliGzipCompress in
-gzip_container.h. Use the ZopfliOptions object to set parameters that affect the
-speed and compression. Use the ZopfliInitOptions function to place the default
-values in the ZopfliOptions first.
+ZopfliCompress supports deflate, gzip and zlib output format with a parameter.
+To support only one individual format, you can instead use ZopfliDeflate in
+deflate.h, ZopfliZlibCompress in zlib_container.h or ZopfliGzipCompress in
+gzip_container.h.
 
-Deflate creates a valid deflate stream in memory, see:
+ZopfliDeflate creates a valid deflate stream in memory, see:
 http://www.ietf.org/rfc/rfc1951.txt
-ZlibCompress creates a valid zlib stream in memory, see:
+ZopfliZlibCompress creates a valid zlib stream in memory, see:
 http://www.ietf.org/rfc/rfc1950.txt
-GzipCompress creates a valid gzip stream in memory, see:
+ZopfliGzipCompress creates a valid gzip stream in memory, see:
 http://www.ietf.org/rfc/rfc1952.txt
 
 This library can only compress, not decompress. Existing zlib or deflate
 libraries can decompress the data.
 
+zopfli_bin.c is separate from the library and contains an example program to
+create very well compressed gzip files. Currently the makefile builds this
+program with the library statically linked in.
+
+To build the binary, use "make". To build the library as a shared Linux library,
+use "make libzopfli". The source code of Zopfli is under src/zopfli.
+
 Zopfli Compression Algorithm was created by Lode Vandevenne and Jyrki
 Alakuijala, based on an algorithm by Jyrki Alakuijala.

zopfli/src/zopfli/blocksplitter.c

@@ -132,16 +132,14 @@ static double SplitCost(size_t i, void* context) {
 static void AddSorted(size_t value, size_t** out, size_t* outsize) {
   size_t i;
   ZOPFLI_APPEND_DATA(value, out, outsize);
-  if (*outsize > 0) {
-    for (i = 0; i < *outsize - 1; i++) {
-      if ((*out)[i] > value) {
-        size_t j;
-        for (j = *outsize - 1; j > i; j--) {
-          (*out)[j] = (*out)[j - 1];
-        }
-        (*out)[i] = value;
-        break;
+  for (i = 0; i + 1 < *outsize; i++) {
+    if ((*out)[i] > value) {
+      size_t j;
+      for (j = *outsize - 1; j > i; j--) {
+        (*out)[j] = (*out)[j - 1];
       }
+      (*out)[i] = value;
+      break;
     }
   }
 }