Now with a real open, but nothing else...

README

@@ -0,0 +1 @@
+Work in progress....

c_src/esqlite_nif.c

@@ -9,42 +9,75 @@
 
 #define MAX_PATHNAME 512 /* unfortunately not in sqlite.h. */
 
+static ErlNifResourceType *esqlite_sqlite3_type = NULL;
+
 static ERL_NIF_TERM _atom_ok;
 static ERL_NIF_TERM _atom_error;
 
+typedef struct {
+  sqlite3 *db;
+} esqlite_sqlite3;
+
+/*
+ */
+static void descruct_esqlite_sqlite3(ErlNifEnv *env, void *esqlite_db)
+{
+  /* The destructor should only be called after all the prepared statements are finalized... */
+  /* TODO keep references, so this is the case */
+  int rc;
+  
+  rc = sqlite3_close(((esqlite_sqlite3 *) esqlite_db)->db);
+  if(rc == SQLITE_BUSY) {
+    /* Can I raise exceptions here errors here? */
+    fprintf(stderr, "Close failed, still busy\n");
+  }
+}
+
 /*
  * Open database. Expects utf-8 input
 */
 static ERL_NIF_TERM esqlite_open_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
-    int rc;
     char filename[MAX_PATHNAME];
     sqlite3 *db;
+    esqlite_sqlite3 *esqldb;
+    ERL_NIF_TERM esqlite_db;
    
-    /* TODO ignore the utf-8 stuff for now */
+    /* TODO ignores the utf-8 stuff for now. nifs only encoding is latin1 */
     if(!enif_get_string(env, argv[0], filename, MAX_PATHNAME, ERL_NIF_LATIN1))
         return enif_make_badarg(env);   
 
-    /* open the database */
+    if(sqlite3_open(filename, &db)) {
-    rc = sqlite3_open(filename, &db);
-    if( rc ) {
       fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db));
       sqlite3_close(db);
-      /* maak een error tuple */
+      /* TODO maak een error tuple */
       return enif_make_tuple2(env, _atom_error, _atom_error); /* todo add error message */
     }
 
-    /* and wrap it in an erlang resource */
+    esqldb = enif_alloc_resource(esqlite_sqlite3_type, sizeof(esqlite_sqlite3));
-    fprintf(stderr, "The database is open.\n");
+    esqldb->db = db;
-    sqlite3_close(db);
+    esqlite_db = enif_make_resource(env, esqldb);
-    fprintf(stderr, "And closed\n");
+    enif_release_resource(esqldb);
-    
+
-    return enif_make_tuple2(env, _atom_ok, _atom_ok);
+    return enif_make_tuple2(env, _atom_ok, esqlite_db);
+}
+
+static ERL_NIF_TERM esqlite_prepare_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+
+  return enif_make_tuple2(env, _atom_ok, _atom_ok);
 }
 
 
 static int on_load(ErlNifEnv* env, void** priv, ERL_NIF_TERM info)
 {
+  ErlNifResourceType *rt = enif_open_resource_type(env, "esqlite", "esqlite_sqlite3_type", 
+						   descruct_esqlite_sqlite3, ERL_NIF_RT_CREATE, NULL);
+  if(!rt) 
+    return -1;
+
+  esqlite_sqlite3_type = rt;
+
   _atom_ok = enif_make_atom(env, "ok");
   _atom_error = enif_make_atom(env, "error");
 
@@ -54,6 +87,7 @@ static int on_load(ErlNifEnv* env, void** priv, ERL_NIF_TERM info)
 
 static ErlNifFunc nif_funcs[] = {
   {"open", 1, esqlite_open_nif},
+  {"prepare", 2, esqlite_prepare_nif}
 };
 
 ERL_NIF_INIT(esqlite, nif_funcs, on_load, NULL, NULL, NULL);

src/esqlite.erl

@@ -5,7 +5,7 @@
 -module(esqlite).
 -author("Maas-Maarten Zeeman <mmzeeman@xs4all.nl>").
 
--export([open/1]).
+-export([open/1, prepare/2]).
 
 -on_load(init/0).
 
@@ -17,3 +17,6 @@ init() ->
 open(_Filename) ->
     exit(nif_library_not_loaded).
 
+prepare(_Db, _Sql) ->
+    exit(nif_library_not_loaded).
+