support js arrays as inputs in ccall

2 files changed, 19 insertions, 3 deletions

diff --git a/src/preamble.js b/src/preamble.js
index 7c2b1a50..e73089cb 100644
--- a/src/preamble.js
+++ b/src/preamble.js
@@ -315,8 +315,10 @@ var globalScope = this;
 //         -s EXPORTED_FUNCTIONS='["_func1","_func2"]'
 //
 // @param ident      The name of the C function (note that C++ functions will be name-mangled - use extern "C")
-// @param returnType The return type of the function, one of the JS types 'number' or 'string' (use 'number' for any C pointer).
-// @param argTypes   An array of the types of arguments for the function (if there are no arguments, this can be ommitted). Types are as in returnType.
+// @param returnType The return type of the function, one of the JS types 'number', 'string' or 'array' (use 'number' for any C pointer, and
+//                   'array' for JavaScript arrays and typed arrays).
+// @param argTypes   An array of the types of arguments for the function (if there are no arguments, this can be ommitted). Types are as in returnType,
+//                   except that 'array' is not possible (there is no way for us to know the length of the array)
 // @param args       An array of the arguments to the function, as native JS values (as in returnType)
 //                   Note that string arguments will be stored on the stack (the JS string will become a C string on the stack).
 // @return           The return value, as a native JS value (as in returnType)
@@ -328,6 +330,11 @@ function ccall(ident, returnType, argTypes, args) {
       var ret = Runtime.stackAlloc(value.length+1);
       writeStringToMemory(value, ret);
       return ret;
+    } else if (type == 'array') {
+      if (!stack) stack = Runtime.stackSave();
+      var ret = Runtime.stackAlloc(value.length);
+      writeArrayToMemory(value, ret);
+      return ret;
     }
     return value;
   }
@@ -335,6 +342,7 @@ function ccall(ident, returnType, argTypes, args) {
     if (type == 'string') {
       return Pointer_stringify(value);
     }
+    assert(type != 'array');
     return value;
   }
   try {
@@ -830,6 +838,13 @@ function writeStringToMemory(string, buffer, dontAddNull) {
 }
 Module['writeStringToMemory'] = writeStringToMemory;
 
+function writeArrayToMemory(array, buffer) {
+  for (var i = 0; i < array.length; i++) {
+    {{{ makeSetValue('buffer', 'i', 'array[i]', 'i8') }}};
+  }
+}
+Module['writeArrayToMemory'] = writeArrayToMemory;
+
 var STRING_TABLE = [];
 
 {{{ unSign }}}
diff --git a/tests/runner.py b/tests/runner.py
index a565b1d2..d23b4ae5 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -5265,6 +5265,7 @@ def process(filename):
         ret = ccall('print_int', null, ['number'], [12]); Module.print(typeof ret);
         ret = ccall('print_float', null, ['number'], [14.56]); Module.print(typeof ret);
         ret = ccall('print_string', null, ['string'], ["cheez"]); Module.print(typeof ret);
+        ret = ccall('print_string', null, ['array'], [[97, 114, 114, 45, 97, 121, 0]]); Module.print(typeof ret);
         ret = ccall('multi', 'number', ['number', 'number', 'number', 'string'], [2, 1.4, 3, 'more']); Module.print([typeof ret, ret]);
         var p = ccall('malloc', 'pointer', ['number'], [4]);
         setValue(p, 650, 'i32');
@@ -5288,7 +5289,7 @@ def process(filename):
 
       Settings.EXPORTED_FUNCTIONS = ['_get_int', '_get_float', '_get_string', '_print_int', '_print_float', '_print_string', '_multi', '_pointer', '_malloc']
 
-      self.do_run(src, '*\nnumber,5\nnumber,3.14\nstring,hello world\n12\nundefined\n14.56\nundefined\ncheez\nundefined\nmore\nnumber,10\n650\nnumber,21\n*\natr\n10\nbret\n53\n*\nstack is ok.\n', post_build=post)
+      self.do_run(src, '*\nnumber,5\nnumber,3.14\nstring,hello world\n12\nundefined\n14.56\nundefined\ncheez\nundefined\narr-ay\nundefined\nmore\nnumber,10\n650\nnumber,21\n*\natr\n10\nbret\n53\n*\nstack is ok.\n', post_build=post)
 
     def test_scriptaclass(self):
         header_filename = os.path.join(self.get_dir(), 'header.h')