added package_root flag to standalone dart vm

runtime/bin/main.cc

Index: runtime/bin/main.cc
diff --git a/runtime/bin/main.cc b/runtime/bin/main.cc
index 014c7230f669592e22a72050b0575c85e8d7784f..d5933045be5266ddd0405d7d3aad6e251b8f4518 100644
--- a/runtime/bin/main.cc
+++ b/runtime/bin/main.cc
@@ -46,6 +46,12 @@ static const char* generate_pprof_symbols_filename = NULL;
 static const char* breakpoint_at = NULL;
 
 
+// Value of the --package_root flag.
+// (This pointer points into an argv buffer and does not need to be
+// free'd.)
+static const char* package_root;

[siva, 2012/04/22 00:14:01]

need to initialize this to NULL otherwise your check below of
package_root == NULL will succeed or fail randomly.

[mattsh, 2012/04/23 16:48:09]

Actually C/C++ guarantee to initialize statics to zero automatically, so it's
OK, but I added the = NULL now for clarity.

+
+
 // Global flag that is used to indicate that we want to compile all the
 // dart functions and not run anything.
 static bool has_compile_all = false;
@@ -65,6 +71,10 @@ static void ProcessBreakpointOption(const char* funcname) {
   breakpoint_at = funcname;
 }
 
+static void ProcessPackageRootOption(const char* arg) {
+  ASSERT(arg != NULL);
+  package_root = arg;
+}
 
 static void ProcessCompileAllOption(const char* compile_all) {
   ASSERT(compile_all != NULL);
@@ -83,7 +93,6 @@ static void ProcessImportMapOption(const char* map) {
   import_map_options->AddArgument(map);
 }
 
-
 static struct {
   const char* option_name;
   void (*process)(const char* option);
@@ -92,6 +101,7 @@ static struct {
   { "--compile_all", ProcessCompileAllOption },
   { "--generate_pprof_symbols=", ProcessPprofOption },
   { "--import_map=", ProcessImportMapOption },
+  { "--package_root=", ProcessPackageRootOption },
   { NULL, NULL }
 };
 
@@ -400,6 +410,12 @@ static bool CreateIsolateAndSetup(const char* name_prefix,
     return false;
   }
 
+  if (package_root != NULL) {
+    Dart_Handle dart_args[1];
+    dart_args[0] =  Dart_NewString(package_root);

[siva, 2012/04/22 00:14:01]

Dart_NewString can return errors and that needs to be checked.
Agreed there are lots of places in this file which does not do this we will fix
those in a different CL.

[mattsh, 2012/04/23 16:48:09]

Added a TODO

[siva, 2012/04/23 17:16:45]

Not sure why this needs to be a TODO and not fixed now.

On 2012/04/23 16:48:09, mattsh wrote:

[mattsh, 2012/04/23 18:12:55]

OK, now added the error handling here and removed the TODO.

+    Dart_Invoke(builtin_lib, Dart_NewString("_setPackageRoot"), 1, dart_args);

[siva, 2012/04/22 00:14:01]

The return value from Dart_NewString and Dart_Invoke should be checked using
Dart_IsError.

[mattsh, 2012/04/23 16:48:09]

Added a TODO to add the error handling.

[siva, 2012/04/23 17:16:45]

Ditto comment about why this needs to be a TODO.

On 2012/04/23 16:48:09, mattsh wrote:

[mattsh, 2012/04/23 18:12:55]

Done.

[mattsh, 2012/04/23 18:12:55]

Done.

+  }
+
   // Load the specified application script into the newly created isolate.
   library = LoadScript(builtin_lib, import_map_options);
   if (Dart_IsError(library)) {