hex_to_raw actually works

.gitignore

@@ -1,3 +1,4 @@
 *.beam
 *.so
 *.o
+*.swp

Makefile

@@ -1,4 +1,4 @@
-OTPROOT=/Users/schacon/otp_src_R13B03
+OTPROOT=/Users/schacon/projects/otp
 INCLUDES = -I$(OTPROOT)/erts/emulator/beam/
 
 # OS X flags.

geef

@@ -0,0 +1,21 @@
+#!/Users/schacon/projects/otp/bin/escript
+%% -*- erlang -*-
+%%! debug verbose -noshell
+
+main([Command|_Args]) ->
+    geef:start(),
+    case Command of
+      "h2r" ->
+        [Object|_Rest] = _Args,
+        Raw = geef:hex_to_raw(Object),
+        io:format("Raw ~w~n", [Raw]);
+      _Else ->
+        usage()
+    end;
+main(_) ->
+    usage().
+        
+usage() ->
+    io:format("usage: ./geef h2r HEX_SHA\n"),
+    halt(1).
+        

geef.c

@@ -3,52 +3,32 @@
 #include <git/common.h>
 #include <git/oid.h>
 
-
-static int
-load(ErlNifEnv* env, void** priv, ERL_NIF_TERM load_info)
-{
-    return 0;
-}
-
-static int
-reload(ErlNifEnv* env, void** priv, ERL_NIF_TERM load_info)
-{
-    return 0;
-}
-
-static int
-upgrade(ErlNifEnv* env, void** priv, void** old_priv,
-          ERL_NIF_TERM load_info)
-{
-    return 0;
-}
-
-static void
-unload(ErlNifEnv* env, void* priv)
-{
-    return;
-}
+#define MAXBUFLEN       1024
 
 static ERL_NIF_TERM
-object_exists(ErlNifEnv* env, ERL_NIF_TERM a1)
+geef_hex_to_raw(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
 {
+  char sha[MAXBUFLEN];
+  (void)memset(&sha, '\0', sizeof(sha));
+
+  if (enif_get_string(env, argv[0], sha, sizeof(sha), ERL_NIF_LATIN1) < 1)
+      return enif_make_badarg(env);
+
   git_oid oid;
-  static char *sha = "ce08fe4884650f067bd5703b6a59a8b3b3c99a09";
+
   printf("sha: %s\n", sha);
   git_oid_mkstr(&oid, sha);
-  //printf("raw: %s", (&oid)->id);
 
-    unsigned long val;
-    if(!enif_get_ulong(env, a1, &val)) {
-        return enif_make_badarg(env);
-    } else {
-        return enif_make_ulong(env, val*2);
-    }
+  ErlNifBinary ibin;
+  enif_alloc_binary(env, 20, &ibin);
+  memcpy(ibin.data, (&oid)->id, 20);
+
+  return enif_make_binary(env, &ibin);
 }
 
 static ErlNifFunc geef_funcs[] =
 {
-    {"object_exists", 1, object_exists}
+  {"hex_to_raw", 1, geef_hex_to_raw}
 };
 
-ERL_NIF_INIT(geef, geef_funcs, load, reload, upgrade, unload)
+ERL_NIF_INIT(geef, geef_funcs, NULL, NULL, NULL, NULL)

geef.erl

@@ -1,10 +1,10 @@
 -module(geef).
--export([start/0, object_exists/1]).
+-export([start/0, hex_to_raw/1]).
 
 start() ->
     erlang:load_nif("geef", 0).
 
-object_exists(_Val) ->
+hex_to_raw(_Val) ->
     nif_error(?LINE).    
 
 nif_error(Line) ->

test

@@ -1,15 +0,0 @@
-#!/Users/schacon/otp_src_R13B03/bin/escript
-%% -*- erlang -*-
-%%! debug verbose -noshell
-
-main([Object]) ->
-    geef:start(),
-    Test = geef:object_exists(4),
-    io:format("exists ~s:~w~n", [Object, Test]);
-main(_) ->
-    usage().
-        
-usage() ->
-    io:format("usage: ./test SHA\n"),
-    halt(1).
-