Add support for freeing and resetting prepared statements.

Now the library starts to be really useful.

Author: lovasoa

Makefile

@@ -4,7 +4,7 @@ EMSCRIPTEN?=/usr/bin
 EMCC=$(EMSCRIPTEN)/emcc -s RESERVED_FUNCTION_POINTERS=2  --closure 1 -O3 -s INLINING_LIMIT=10
 CC=clang -O2
 CFLAGS=-DSQLITE_OMIT_LOAD_EXTENSION -DSQLITE_DISABLE_LFS -DLONGDOUBLE_TYPE=double -DSQLITE_INT64_TYPE="long long int" -DSQLITE_THREADSAFE=0
-EXPORTED_FUNCTIONS="['_sqlite3_open', '_sqlite3_close', '_sqlite3_exec', '_sqlite3_free', '_sqlite3_data_count', '_sqlite3_column_type', '_sqlite3_column_text', '_sqlite3_column_double', '_sqlite3_prepare_v2', '_sqlite3_step', '_sqlite3_bind_text', '_sqlite3_bind_double']"
+EXPORTED_FUNCTIONS="['_sqlite3_open', '_sqlite3_close', '_sqlite3_exec', '_sqlite3_free', '_sqlite3_data_count', '_sqlite3_column_type', '_sqlite3_column_text', '_sqlite3_column_double', '_sqlite3_prepare_v2', '_sqlite3_step', '_sqlite3_bind_text', '_sqlite3_bind_double', '_sqlite3_reset', '_sqlite3_finalize']"
 
 
 all: js/sql.js test/benchmark.js test/benchmark

README.md

@@ -29,6 +29,17 @@ stmt.bind([1, 'world']);
 
 // Fetch the results of the query
 while (stmt.step()) console.log(stmt.get()); // Will print [1, 'world']
+
+// Resets the statement, so it can be used again with other values
+stmt.reset()
+// Bind other values
+stmt.bind([0, 'hello']);
+while (stmt.step()) console.log(stmt.get()); // Will print [0, 'hello']
+
+// free the memory used by the statement
+stmt.free();
+// You can not use your statement anymore once it has been freed.
+// But not freeing your statements causes memory leaks. You don't want that.
 ```
 
 ## Differences from the original sql.js

js/api.coffee

@@ -60,6 +60,8 @@ class Statement
 	bind : (values) ->
 		@bindValue v,i+1 for v,i in values # Index of the leftmost parameter is 1
 		null
+	reset : -> sqlite3_reset @stmt
+	free: -> sqlite3_finalize @stmt
 
 class Database
 	# Open a new database:
@@ -130,6 +132,10 @@ sqlite3_data_count = Module.cwrap 'sqlite3_data_count', 'number', ['number']
 sqlite3_column_double = Module.cwrap 'sqlite3_column_double', 'number', ['number', 'number']
 sqlite3_column_text = Module.cwrap 'sqlite3_column_text', 'string', ['number', 'number']
 sqlite3_column_type = Module.cwrap 'sqlite3_column_type', 'number', ['number', 'number']
+# int sqlite3_reset(sqlite3_stmt *pStmt);
+sqlite3_reset = Module.cwrap 'sqlite3_reset', 'number', ['number']
+# int sqlite3_finalize(sqlite3_stmt *pStmt);
+sqlite3_finalize = Module.cwrap 'sqlite3_finalize', 'number', ['number']
 
 # Global constants
 NULL = 0 # Null pointer