Make a better distinction between zopfli binary and library

2 files changed, 108 insertions, 0 deletions

diff --git a/zopfli.h b/zopfli.h
new file mode 100644
index 0000000..f520b1e
--- /dev/null
+++ b/zopfli.h
@@ -0,0 +1,71 @@
+/*
+Copyright 2013 Google Inc. All Rights Reserved.
+Author: lode@google.com (Lode Vandevenne)
+*/
+
+#ifndef UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_
+#define UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_
+
+#include <stdlib.h> /* for size_t */
+
+/*
+Options used throughout the program.
+*/
+typedef struct ZopfliOptions {
+  /* Whether to print output */
+  int verbose;
+
+  /*
+  Maximum amount of times to rerun forward and backward pass to optimize LZ77
+  compression cost. Good values: 10, 15 for small files, 5 for files over
+  several MB in size or it will be too slow.
+  */
+  int numiterations;
+
+  /*
+  If true, splits the data in multiple deflate blocks with optimal choice
+  for the block boundaries. Block splitting gives better compression. Default:
+  true (1).
+  */
+  int blocksplitting;
+
+  /*
+  If true, chooses the optimal block split points only after doing the iterative
+  LZ77 compression. If false, chooses the block split points first, then does
+  iterative LZ77 on each individual block. Depending on the file, either first
+  or last gives the best compression. Default: false (0).
+  */
+  int blocksplittinglast;
+
+  /*
+  Maximum amount of blocks to split into (0 for unlimited, but this can give
+  extreme results that hurt compression on some files). Default value: 15.
+  */
+  int blocksplittingmax;
+} ZopfliOptions;
+
+/* Initializes options with default values. */
+void ZopfliInitOptions(ZopfliOptions* options);
+
+/* Output format */
+typedef enum {
+  ZOPFLI_FORMAT_GZIP,
+  ZOPFLI_FORMAT_ZLIB,
+  ZOPFLI_FORMAT_DEFLATE
+} ZopfliFormat;
+
+/*
+Compresses according to the given output format and appends the result to the
+output.
+
+options: global program options
+output_type: the output format to use
+out: pointer to the dynamic output array to which the result is appended. Must
+  be freed after use
+outsize: pointer to the dynamic output array size
+*/
+void ZopfliCompress(const ZopfliOptions* options, ZopfliFormat output_type,
+                    const unsigned char* in, size_t insize,
+                    unsigned char** out, size_t* outsize);
+
+#endif  /* UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_ */
diff --git a/zopfli_lib.c b/zopfli_lib.c
new file mode 100644
index 0000000..99d3f7d
--- /dev/null
+++ b/zopfli_lib.c
@@ -0,0 +1,37 @@
+/*
+Copyright 2013 Google Inc. All Rights Reserved.
+Author: lode@google.com (Lode Vandevenne)
+*/
+
+#include "zopfli.h"
+
+#include "deflate.h"
+#include "gzip_container.h"
+#include "zlib_container.h"
+
+#include <assert.h>
+
+void ZopfliInitOptions(ZopfliOptions* options) {
+  options->verbose = 0;
+  options->numiterations = 15;
+  options->blocksplitting = 1;
+  options->blocksplittinglast = 0;
+  options->blocksplittingmax = 15;
+}
+
+void ZopfliCompress(const ZopfliOptions* options, ZopfliFormat output_type,
+                    const unsigned char* in, size_t insize,
+                    unsigned char** out, size_t* outsize)
+{
+  if (output_type == ZOPFLI_FORMAT_GZIP) {
+    ZopfliGzipCompress(options, in, insize, out, outsize);
+  } else if (output_type == ZOPFLI_FORMAT_ZLIB) {
+    ZopfliZlibCompress(options, in, insize, out, outsize);
+  } else if (output_type == ZOPFLI_FORMAT_DEFLATE) {
+    unsigned char bp = 0;
+    ZopfliDeflate(options, 2 /* Dynamic block */, 1,
+                  in, insize, &bp, out, outsize);
+  } else {
+    assert(0);
+  }
+}