Added PrinterDriverInfo and PrintBackend::GetPrinterDriverInfo for windows.

printing/backend/print_backend_win.cc

Index: printing/backend/print_backend_win.cc
diff --git a/printing/backend/print_backend_win.cc b/printing/backend/print_backend_win.cc
index 01be277fe11f72dc23cb987fddaa2a5f30dcd6b2..843143dd8a006f8a3f2948cf998a7c53e07ff053 100644
--- a/printing/backend/print_backend_win.cc
+++ b/printing/backend/print_backend_win.cc
@@ -7,6 +7,8 @@
 #include <objidl.h>
 #include <winspool.h>
 
+#include "base/file_path.h"
+#include "base/file_version_info.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/string_piece.h"
 #include "base/utf_string_conversions.h"
@@ -47,6 +49,9 @@ class PrintBackendWin : public PrintBackend {
   virtual bool GetPrinterCapsAndDefaults(const std::string& printer_name,
                                          PrinterCapsAndDefaults* printer_info);
 
+  virtual bool GetPrinterDriverInfo(const std::string& printer_name,
+                                    PrinterDriverInfo* driver_info);
+
   virtual bool IsValidPrinter(const std::string& printer_name);
 };
 
@@ -131,12 +136,11 @@ bool PrintBackendWin::GetPrinterCapsAndDefaults(
       DCHECK(SUCCEEDED(hr));
       printer_info->caps_mime_type = "text/xml";
     }
-    // TODO(sanjeevr): Add ScopedPrinterHandle
-    HANDLE printer_handle = NULL;
-    OpenPrinter(const_cast<LPTSTR>(printer_name_wide.c_str()), &printer_handle,
-                NULL);
+    ScopedPrinterHandle printer_handle;
+    OpenPrinter(const_cast<LPTSTR>(printer_name_wide.c_str()),
+                printer_handle.Receive(), NULL);
     DCHECK(printer_handle);
-    if (printer_handle) {
+    if (printer_handle.IsValid()) {
       LONG devmode_size = DocumentProperties(
           NULL, printer_handle, const_cast<LPTSTR>(printer_name_wide.c_str()),
           NULL, NULL, 0);
@@ -166,24 +170,56 @@ bool PrintBackendWin::GetPrinterCapsAndDefaults(
           printer_info->defaults_mime_type = "text/xml";
         }
       }
-      ClosePrinter(printer_handle);
     }
     XPSModule::CloseProvider(provider);
   }
   return true;
 }
 
-bool PrintBackendWin::IsValidPrinter(const std::string& printer_name) {
+// Gets the information about driver for a specific printer.
+bool PrintBackendWin::GetPrinterDriverInfo(const std::string& printer_name,
+                                           PrinterDriverInfo* driver_info) {
+  DCHECK(driver_info);
+  ScopedPrinterHandle printer_handle;
   std::wstring printer_name_wide = UTF8ToWide(printer_name);
-  HANDLE printer_handle = NULL;
-  OpenPrinter(const_cast<LPTSTR>(printer_name_wide.c_str()), &printer_handle,
-              NULL);
-  bool ret = false;
-  if (printer_handle) {
-    ret = true;
-    ClosePrinter(printer_handle);
+  if (!::OpenPrinter(const_cast<LPTSTR>(printer_name_wide.c_str()),
+                     printer_handle.Receive(), NULL)) {
+    return false;
+  }
+  DCHECK(printer_handle.IsValid());
+  DWORD bytes_needed = 0;
+  ::GetPrinterDriver(printer_handle, NULL, 6, NULL, 0, &bytes_needed);
+  scoped_array<BYTE> driver_info_buffer(new BYTE[bytes_needed]);
+  if (!::GetPrinterDriver(printer_handle, NULL, 6, driver_info_buffer.get(),
+                          bytes_needed, &bytes_needed)) {
+    return false;
   }
-  return ret;
+  if (!bytes_needed)
+    return false;
+  const DRIVER_INFO_6* driver_info_6 =
+      reinterpret_cast<DRIVER_INFO_6*>(driver_info_buffer.get());
+
+  if (driver_info_6->pName)
+    driver_info->driver_name = WideToUTF8(driver_info_6->pName);
+
+  if (driver_info_6->pDriverPath) {
+    scoped_ptr<FileVersionInfo> version_info(
+        FileVersionInfo::CreateFileVersionInfo(
+            FilePath(driver_info_6->pDriverPath)));
+    driver_info->driver_version = WideToUTF8(version_info->file_version());
+    driver_info->product_name = WideToUTF8(version_info->product_name());
+    driver_info->product_version = WideToUTF8(version_info->product_version());
+  }
+
+  return true;
+}
+
+bool PrintBackendWin::IsValidPrinter(const std::string& printer_name) {
+  std::wstring printer_name_wide = UTF8ToWide(printer_name);
+  ScopedPrinterHandle printer_handle;
+  OpenPrinter(const_cast<LPTSTR>(printer_name_wide.c_str()),
+              printer_handle.Receive(), NULL);
+  return printer_handle.IsValid();
 }
 
 scoped_refptr<PrintBackend> PrintBackend::CreateInstance(