[PATCH v2 4/5] mshtml: Protect storage with a mutex.

[Hans Leidekker]

Signed-off-by: Hans Leidekker 
---
 dlls/mshtml/htmlstorage.c | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/dlls/mshtml/htmlstorage.c b/dlls/mshtml/htmlstorage.c
index 502eb8c25ab..1793cfae184 100644
--- a/dlls/mshtml/htmlstorage.c
+++ b/dlls/mshtml/htmlstorage.c
@@ -191,9 +191,21 @@ static WCHAR *build_filename(const WCHAR *hostname)
     return ret;
 }

+static WCHAR *build_mutexname(const WCHAR *filename)
+{
+    WCHAR *ret, *ptr;
+    ret = wcsdup(filename);
+    if(!ret)
+        return NULL;
+    for(ptr = ret; *ptr; ptr++)
+        if(*ptr == '\') *ptr = '_';
+    return ret;
+}
+
 struct storage {
     WCHAR *filename;
     IXMLDOMDocument *doc;
+    HANDLE mutex;
 };

static void close_storage(struct storage *storage)
@@ -201,6 +213,8 @@ static void close_storage(struct storage *storage)
     free(storage->filename);
     if(storage->doc)
         IXMLDOMDocument_Release(storage->doc);
+    ReleaseMutex(storage->mutex);
+    CloseHandle(storage->mutex);
     free(storage);
 }

@@ -210,7 +224,7 @@ static HRESULT open_storage(const WCHAR *hostname, struct storage **ret)
     HRESULT hres = E_OUTOFMEMORY;
     VARIANT var;
     VARIANT_BOOL success;
-    WCHAR *ptr;
+    WCHAR *mutexname, *ptr;

storage = calloc(1, sizeof(*storage));
     if(!storage)
@@ -220,6 +234,18 @@ static HRESULT open_storage(const WCHAR *hostname, struct storage **ret)
     if(!storage->filename)
         goto done;

+    mutexname = build_mutexname(storage->filename);
+    if(!mutexname)
+        goto done;
+
+    storage->mutex = CreateMutexW(NULL, FALSE, mutexname);
+    free(mutexname);
+    if(!storage->mutex) {
+        hres = HRESULT_FROM_WIN32(GetLastError());
+        goto done;
+    }
+    WaitForSingleObject(storage->mutex, INFINITE);
+
     *(ptr = wcsrchr(storage->filename, '\')) = 0;
     if(!create_path(storage->filename)) {
         hres = E_FAIL;