Added custom functions.

Author: MFAshby

Makefile

@@ -4,14 +4,15 @@ EMSCRIPTEN?=/usr/bin
 
 EMCC=$(EMSCRIPTEN)/emcc
 
-CFLAGS=-DSQLITE_OMIT_LOAD_EXTENSION -DSQLITE_DISABLE_LFS -DLONGDOUBLE_TYPE=double -DSQLITE_INT64_TYPE="long long int" -DSQLITE_THREADSAFE=0
+CFLAGS=-DSQLITE_OMIT_LOAD_EXTENSION -DSQLITE_DISABLE_LFS -DLONGDOUBLE_TYPE=double -DSQLITE_INT64_TYPE="long long int" -DSQLITE_THREADSAFE=0 -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_PARENTHESIS
 
 all: js/sql.js
 
-debug: EMFLAGS= -O1 -g -s INLINING_LIMIT=10 
+# RESERVED_FUNCTION_POINTERS setting is used for registering custom functions
+debug: EMFLAGS= -O1 -g -s INLINING_LIMIT=10 -s RESERVED_FUNCTION_POINTERS=64
 debug: js/sql-debug.js
 
-optimized: EMFLAGS= --memory-init-file 0 --closure 1 -O3 -s INLINING_LIMIT=50
+optimized: EMFLAGS= --memory-init-file 0 --closure 1 -O3 -s INLINING_LIMIT=50 -s RESERVED_FUNCTION_POINTERS=64
 optimized: js/sql-optimized.js
 
 js/sql.js: optimized

coffee/api-data.coffee

@@ -39,3 +39,6 @@ SQLite.FLOAT=2
 SQLite.TEXT=3
 SQLite.BLOB=4
 SQLite.NULL=5
+
+# Encodings, used for registering functions. 
+SQLite.UTF8=1

coffee/api.coffee

@@ -413,6 +413,53 @@ class Database
 		@handleError sqlite3_close_v2 @db
 		FS.unlink '/' + @filename
 		@db = null
+		
+	### Register a custom function with SQLite
+  @param name [String] the name of the function as referenced in SQL statements.
+  @param numParams [Number] the number of parameters the function expects.
+  @param func [Function] the actual function to be executed.
+  @param dbg_func [Function, optional] useful for breakpointing and testing the wrapper function.
+  ###
+	'create_function': (name, numParams, func, dbg_func=(->)) ->
+		wrapped_func = (cx, argc, argv) ->
+			# Debug function, useful for breakpointing if you need to debug this
+			dbg_func()
+			
+			# Parse the args from sqlite into JS objects
+			args = []
+			for i in [0..argc]
+				value_ptr = getValue(argv+(4*i), 'i32')
+				value_type = sqlite3_value_type(value_ptr)
+				data_func = switch
+					when value_type == 1 then sqlite3_value_int
+					when value_type == 2 then sqlite3_value_double
+					when value_type == 3 then sqlite3_value_text
+					when value_type == 4 then (ptr) -> 
+						size = sqlite3_value_bytes(ptr)
+						blob_ptr = sqlite3_value_blob(ptr)
+						blob_arg = new Uint8Array(size)
+						blob_arg[j] = HEAP8[blob_ptr+j] for j in [0 ... size]
+						blob_arg
+					else (ptr) -> null
+
+				arg = data_func(value_ptr)
+				args.push arg
+				
+			# Invoke the user defined function with arguments from SQLite
+			result = func.apply(null, args)
+			
+			# Return the result of the user defined function to SQLite
+			if not result
+				sqlite3_result_null cx
+			else 
+				switch typeof(result)
+					when 'number' then sqlite3_result_double(cx, result)
+					when 'string' then sqlite3_result_text(cx, result, -1, -1)
+					
+		# Generate a pointer to the wrapped, user defined function, and register with SQLite.
+		func_ptr = Runtime.addFunction(wrapped_func)
+		@handleError sqlite3_create_function_v2 @db, name, numParams, SQLite.UTF8, 0, func_ptr, 0, 0, 0
+		return @
 
 	### Analyze a result code, return null if no error occured, and throw
 	an error with a descriptive message otherwise

coffee/exports.coffee

@@ -41,6 +41,18 @@ sqlite3_clear_bindings = Module['cwrap'] 'sqlite3_clear_bindings', 'number', ['n
 # int sqlite3_finalize(sqlite3_stmt *pStmt);
 sqlite3_finalize = Module['cwrap'] 'sqlite3_finalize', 'number', ['number']
 
+## Create custom functions
+sqlite3_create_function_v2 = Module['cwrap'] 'sqlite3_create_function_v2', 'number', ['number', 'string', 'number', 'number', 'number', 'number', 'number', 'number', 'number']
+sqlite3_value_type = Module['cwrap'] 'sqlite3_value_type', 'number', ['number']
+sqlite3_value_bytes = Module['cwrap'] 'sqlite3_value_bytes', 'number', ['number']
+sqlite3_value_text = Module['cwrap'] 'sqlite3_value_text', 'string', ['number']
+sqlite3_value_int = Module['cwrap'] 'sqlite3_value_int', 'number', ['number']
+sqlite3_value_blob = Module['cwrap'] 'sqlite3_value_blob', 'number', ['number']
+sqlite3_value_double = Module['cwrap'] 'sqlite3_value_double', 'number', ['number']
+sqlite3_result_double = Module['cwrap'] 'sqlite3_result_double', '', ['number', 'number']
+sqlite3_result_null = Module['cwrap'] 'sqlite3_result_null', '', ['number']
+sqlite3_result_text = Module['cwrap'] 'sqlite3_result_text', '', ['number', 'string', 'number', 'number']
+
 # Export the API
 this['SQL'] = {'Database':Database}
 Module[i] = this['SQL'][i] for i of this['SQL']

exported_functions

@@ -22,5 +22,15 @@
  "_sqlite3_reset",
  "_sqlite3_clear_bindings",
  "_sqlite3_finalize",
- "_sqlite3_close_v2"
+ "_sqlite3_close_v2",
+ "_sqlite3_create_function_v2",
+ "_sqlite3_value_bytes",
+ "_sqlite3_value_type",
+ "_sqlite3_value_text",
+ "_sqlite3_value_int", 
+ "_sqlite3_value_blob",
+ "_sqlite3_value_double",
+ "_sqlite3_result_double",
+ "_sqlite3_result_null",
+ "_sqlite3_result_text"
 ]