Add GitRekt.Git.object_zlib_inflate/1

See issues #1 and #3 for more details.

apps/gitrekt/c_src/geef.c

@@ -190,6 +190,7 @@ static ErlNifFunc geef_funcs[] =
 	{"object_repository", 1, geef_object_repository},
 	{"object_lookup", 2, geef_object_lookup},
 	{"object_id", 1, geef_object_id},
+	{"object_zlib_inflate", 1, geef_object_zlib_inflate},
 	{"commit_tree", 1, geef_commit_tree},
 	{"commit_tree_id", 1, geef_commit_tree_id},
 	{"commit_create",  8, geef_commit_create},

apps/gitrekt/c_src/object.c

@@ -2,6 +2,7 @@
 #include "repository.h"
 #include "object.h"
 #include "oid.h"
+#include <zlib.h>
 #include <string.h>
 #include <git2.h>
 
@@ -113,3 +114,39 @@ geef_object_id(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
 
 	return enif_make_tuple2(env, atoms.ok, enif_make_binary(env, &bin));
 }
+
+ERL_NIF_TERM
+geef_object_zlib_inflate(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
+{
+	ErlNifBinary bin;
+    z_stream z;
+    z.zalloc = Z_NULL;
+    z.zfree = Z_NULL;
+    z.opaque = Z_NULL;
+
+	if (!enif_inspect_binary(env, argv[0], &bin))
+		return enif_make_badarg(env);
+
+	if (!geef_terminate_binary(&bin)) {
+        enif_release_binary(&bin);
+        return geef_oom(env);
+    }
+
+    char output[bin.size*2];
+
+    z.avail_in = bin.size;
+    z.next_in = bin.data;
+    z.avail_out = bin.size*2;
+    z.next_out = output;
+
+    inflateInit(&z);
+    inflate(&z, Z_NO_FLUSH);
+    inflateEnd(&z);
+
+    if (enif_alloc_binary(z.total_out, &bin) < 0)
+        return -1;
+
+    memcpy(bin.data, output, z.total_out);
+
+	return enif_make_tuple3(env, atoms.ok, enif_make_binary(env, &bin), enif_make_ulong(env, z.total_in));
+}

apps/gitrekt/c_src/object.h

@@ -15,10 +15,11 @@ typedef struct {
 ERL_NIF_TERM geef_object_repository(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
 ERL_NIF_TERM geef_object_lookup(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
 ERL_NIF_TERM geef_object_id(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+ERL_NIF_TERM geef_object_zlib_inflate(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
 
 ERL_NIF_TERM geef_object_type2atom(const git_otype type);
-git_otype geef_object_atom2type(ERL_NIF_TERM term);
 
+git_otype geef_object_atom2type(ERL_NIF_TERM term);
 void geef_object_free(ErlNifEnv *env, void *cd);
 
 #endif

apps/gitrekt/lib/gitrekt/git.ex

@@ -296,6 +296,14 @@ defmodule GitRekt.Git do
     raise Code.LoadError, file: @nif_path_lib
   end
 
+  @doc """
+  Inflates the given `data` with *zlib*.
+  """
+  @spec object_zlib_inflate(binary) :: {:ok, binary, non_neg_integer} | {:error, term}
+  def object_zlib_inflate(_data) do
+    raise Code.LoadError, file: @nif_path_lib
+  end
+
   @doc """
   Returns the tree id for the given `commit`.
   """