Implemented backup_init

c_src/esqlite3_nif.c

@@ -26,10 +26,12 @@
 #include "queue.h"
 
 #define MAX_ATOM_LENGTH 255         /* from atom.h, not exposed in erlang include */
+#define MAX_SQLITE_NAME_LENGTH  255 /* Maximum name length. Using longer will return misuse */
 #define MAX_PATHNAME 512            /* unfortunately not in sqlite.h. */
 
 static ErlNifResourceType *esqlite_connection_type = NULL;
 static ErlNifResourceType *esqlite_statement_type = NULL;
+static ErlNifResourceType *esqlite_backup_type = NULL;
 
 /* database connection context */
 typedef struct {
@@ -325,6 +327,7 @@ update_callback(void *arg, int sqlite_operation_type, char const *sqlite_databas
 
     cmd->type = cmd_notification;
     cmd->arg = enif_make_tuple3(cmd->env, type, table, rowid);
+
     push_command(cmd->env, db, cmd);
 }
 
@@ -657,11 +660,10 @@ static ERL_NIF_TERM
 do_reset(ErlNifEnv *env, sqlite3 *db, sqlite3_stmt *stmt)
 {
     int rc = sqlite3_reset(stmt);
-
-    if(rc == SQLITE_OK)
-        return make_atom(env, "ok");
-
+    if(rc != SQLITE_OK)
         return make_sqlite3_error_tuple(env, rc, db);
+
+    return make_atom(env, "ok");
 }
 
 static ERL_NIF_TERM
@@ -730,9 +732,63 @@ do_column_types(ErlNifEnv *env, sqlite3_stmt *stmt)
 }
 
 static ERL_NIF_TERM
-do_backup_init(ErlNifEnv *env, const ERL_NIF_TERM arg)
+do_backup_init(ErlNifEnv *env, sqlite3 *db, const ERL_NIF_TERM arg)
 {
-    return make_atom(env, "todo");
+    int rc;
+    int tuple_arity;
+    const ERL_NIF_TERM *elements;
+    sqlite3_backup *backup;
+    unsigned int size;
+    char dst_name[MAX_SQLITE_NAME_LENGTH];
+    char src_name[MAX_SQLITE_NAME_LENGTH];
+    esqlite_connection *src;
+    esqlite_backup *esqlite_backup;
+    ERL_NIF_TERM erl_backup_term;
+
+    if(db == NULL) {
+        return make_error_tuple(env, "dst_closed");
+    }
+
+    if(!enif_get_tuple(env, arg, &tuple_arity, &elements)) {
+        return make_error_tuple(env, "no_tuple");
+    }
+
+    if(tuple_arity != 3) {
+        return make_error_tuple(env, "invalid_tuple");
+    }
+
+    size = enif_get_string(env, elements[0], dst_name, MAX_PATHNAME, ERL_NIF_LATIN1);
+    if(size <= 0)
+        return make_error_tuple(env, "invalid_dst_name");
+
+    if(!enif_get_resource(env, elements[1], esqlite_connection_type, (void **) &src)) {
+        return make_error_tuple(env, "invalid_src_db");
+    }
+    if(!src->db) {
+        return make_error_tuple(env, "src_closed");
+    }
+	
+    size = enif_get_string(env, elements[2], src_name, MAX_PATHNAME, ERL_NIF_LATIN1);
+    if(size <= 0)
+        return make_error_tuple(env, "invalid_src_name");
+
+    backup = sqlite3_backup_init(db, dst_name, src->db, src_name);
+    if(backup == NULL) {
+        return make_sqlite3_error_tuple(env, sqlite3_errcode(db), db);
+    }
+
+    esqlite_backup = enif_alloc_resource(esqlite_backup_type, sizeof(esqlite_backup));
+    if(!esqlite_backup) {
+        // Release backup resouces 
+        (void) sqlite3_backup_finish(backup);
+        return make_error_tuple(env, "no_memory");
+    }
+
+    esqlite_backup->backup = backup;
+    erl_backup_term = enif_make_resource(env, esqlite_backup);
+    enif_release_resource(esqlite_backup);
+
+    return make_ok_tuple(env, erl_backup_term);
 }
 
 static ERL_NIF_TERM
@@ -805,7 +861,7 @@ evaluate_command(esqlite_command *cmd, esqlite_connection *conn)
         case cmd_column_types:
             return do_column_types(cmd->env, stmt->statement);
         case cmd_backup_init:
-            return do_backup_init(cmd->env, cmd->arg);
+            return do_backup_init(cmd->env, conn->db, cmd->arg);
         case cmd_backup_step:
             return do_backup_step(cmd->env, cmd->arg);
         case cmd_backup_remaining:
@@ -1406,7 +1462,6 @@ esqlite_backup_finish(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
     cmd->ref = enif_make_copy(cmd->env, argv[2]);
     cmd->pid = pid;
     cmd->arg = enif_make_copy(cmd->env, argv[1]);
-    cmd->stmt = NULL;
 
     return push_command(env, conn, cmd);
 }
@@ -1556,25 +1611,20 @@ on_load(ErlNifEnv* env, void** priv, ERL_NIF_TERM info)
 {
     ErlNifResourceType *rt;
 
-    rt = enif_open_resource_type(env, "esqlite3_nif", "esqlite_connection_type",
-            destruct_esqlite_connection, ERL_NIF_RT_CREATE, NULL);
-    if(!rt)
-        return -1;
+    rt = enif_open_resource_type(env, "esqlite3_nif", "esqlite_connection_type", destruct_esqlite_connection,
+            ERL_NIF_RT_CREATE, NULL);
+    if(!rt) return -1;
     esqlite_connection_type = rt;
 
-    rt =  enif_open_resource_type(env, "esqlite3_nif", "esqlite_statement_type",
-            destruct_esqlite_statement, ERL_NIF_RT_CREATE, NULL);
-    if(!rt)
-        return -1;
+    rt =  enif_open_resource_type(env, "esqlite3_nif", "esqlite_statement_type", destruct_esqlite_statement,
+            ERL_NIF_RT_CREATE, NULL);
+    if(!rt) return -1;
     esqlite_statement_type = rt;
 
-    rt =  enif_open_resource_type(env, "esqlite3_nif", "esqlite_backup_type",
-            destruct_esqlite_backup, ERL_NIF_RT_CREATE, NULL);
-    if(!rt)
-        return -1;
-    esqlite_statement_type = rt;
-
-
+    rt =  enif_open_resource_type(env, "esqlite3_nif", "esqlite_backup_type", destruct_esqlite_backup,
+            ERL_NIF_RT_CREATE, NULL);
+    if(!rt) return -1;
+    esqlite_backup_type = rt;
 
     atom_esqlite3 = make_atom(env, "esqlite3");
 

src/esqlite3.erl

@@ -36,6 +36,7 @@
          fetchall/3,
          column_names/1, column_names/2,
          column_types/1, column_types/2,
+         backup_init/4, backup_init/5,
          close/1, close/2,
          flush/0
         ]).
@@ -56,8 +57,13 @@
           raw_statement :: esqlite_nif:raw_statement()
 }).
 
+-record(backup, {
+          raw_backup :: esqlite_nif:raw_backup()
+}).
+
 -type connection() :: #connection{}. 
 -type statement() :: #statement{}.
+-type backup() :: #backup{}.
 -type sql() :: esqlite_nif:sql().
 
 %% erlang -> sqlite type conversions
@@ -528,6 +534,19 @@ column_types(#statement{raw_statement=RawStatement, raw_connection=RawConnection
     ok = esqlite3_nif:column_types(RawConnection, RawStatement, Ref, self()),
     receive_answer(RawConnection, Ref, Timeout).
 
+%% @doc Initialize a backup procedure.
+-spec backup_init(connection(), string(), connection(), string()) -> {ok, backup()} | {error, _}.
+backup_init(Dest, DestName, Src, SrcName) ->
+    backup_init(Dest, DestName, Src, SrcName, ?DEFAULT_TIMEOUT).
+
+%% @doc Initialize a backup procedure
+-spec backup_init(connection(), string(), connection(), string(), timeout()) -> {ok, backup()} | {error, _}.
+backup_init(#connection{raw_connection=Dest}, DestName, #connection{raw_connection=Src}, SrcName, Timeout) ->
+    Ref = make_ref(),
+    ok = esqlite3_nif:backup_init(Dest, DestName, Src, SrcName, Ref, self()),
+    receive_answer(Dest, Ref, Timeout).
+
+
 %% @doc Close the database
 -spec close(connection()) -> ok | {error, _}.
 close(Connection) ->

src/esqlite3_nif.erl

@@ -49,7 +49,7 @@
 -type raw_backup() :: reference().
 -type sql() :: iodata(). 
 
--export_type([raw_connection/0, raw_statement/0, sql/0]).
+-export_type([raw_connection/0, raw_statement/0, raw_backup/0, sql/0]).
 
 -on_load(init/0).
 

test/esqlite_test.erl

@@ -293,7 +293,6 @@ reset_test() ->
 
     ok.
 
-
 foreach_test() ->
     {ok, Db} = esqlite3:open(":memory:"),
 
@@ -441,6 +440,15 @@ prepare_and_close_connection_test() ->
 
     ok.
 
+backup_test() ->
+    {ok, Dest} = esqlite3:open("test1.sql"),
+    {ok, Source} = esqlite3:open("test2.sql"),
+
+    {ok, Backup} = esqlite3:backup_init(Dest, "main", Source, "main"),
+
+    ok.
+
+
 sqlite_version_test() ->
     {ok, Db} = esqlite3:open(":memory:"),
     {ok, Stmt} = esqlite3:prepare("select sqlite_version() as sqlite_version;", Db),