Implement QFileSystemIterator for windows.

The search is implemented using FindFirstFileEx(). Following
optimizations are done
  * Using large Fetch buffer on Windows 7
  * Querying only the long file name
  * Querying for directories only, depending on QDir::Filters

Reviewed-by: Joao

1 files changed, 80 insertions, 4 deletions

diff --git a/src/corelib/io/qfilesystemiterator_win.cpp b/src/corelib/io/qfilesystemiterator_win.cpp
index 3c734967dd..373a50a653 100644
--- a/src/corelib/io/qfilesystemiterator_win.cpp
+++ b/src/corelib/io/qfilesystemiterator_win.cpp
@@ -40,26 +40,102 @@
 ****************************************************************************/
 
 #include "qfilesystemiterator_p.h"
+#include "qfilesystemengine_p.h"
+#include "qplatformdefs.h"
 
 QT_BEGIN_NAMESPACE
 
+bool done = true;
+
 QFileSystemIterator::QFileSystemIterator(const QFileSystemEntry &entry, QDir::Filters filters,
                                          const QStringList &nameFilters, QDirIterator::IteratorFlags flags)
+    : nativePath(entry.nativeFilePath())
+    , dirPath(entry.filePath())
+    , findFileHandle(INVALID_HANDLE_VALUE)
+    , uncFallback(false)
+    , uncShareIndex(0)
+    , onlyDirs(false)
 {
-    Q_UNUSED(entry)
-    Q_UNUSED(filters)
     Q_UNUSED(nameFilters)
     Q_UNUSED(flags)
+    if (nativePath.endsWith(QLatin1String(".lnk"))) {
+        QFileSystemMetaData metaData;
+        QFileSystemEntry link = QFileSystemEngine::getLinkTarget(entry, metaData);
+        nativePath = link.nativeFilePath();
+    }
+    if (!nativePath.endsWith(QLatin1Char('\\')))
+        nativePath.append(QLatin1Char('\\'));
+    nativePath.append(QLatin1Char('*'));
+    if (!dirPath.endsWith(QLatin1Char('//')))
+        dirPath.append(QLatin1Char('//'));
+    if ((filters & (QDir::Dirs|QDir::Drives)) && (!(filters & (QDir::Files))))
+        onlyDirs = true;
 }
 
 QFileSystemIterator::~QFileSystemIterator()
 {
+   if (findFileHandle != INVALID_HANDLE_VALUE)
+        FindClose(findFileHandle);
 }
 
 bool QFileSystemIterator::advance(QFileSystemEntry &fileEntry, QFileSystemMetaData &metaData)
 {
-    Q_UNUSED(fileEntry)
-    Q_UNUSED(metaData)
+    bool haveData = false;
+    WIN32_FIND_DATA findData;
+
+    if (findFileHandle == INVALID_HANDLE_VALUE && !uncFallback) {
+        haveData = true;
+        DWORD dwAdditionalFlags  = 0;
+        if (QSysInfo::windowsVersion() >= QSysInfo::WV_WINDOWS7)
+            dwAdditionalFlags = 2;  // FIND_FIRST_EX_LARGE_FETCH
+        int searchOps =  0;         // FindExSearchNameMatch
+        if (onlyDirs)
+            searchOps = 1 ;         // FindExSearchLimitToDirectories
+#if !defined(Q_OS_WINCE)
+        int infoLevel = 1 ;         // FindExInfoBasic;
+#else
+        int infoLevel = 0;          // FindExInfoStandard;
+#endif
+        findFileHandle = FindFirstFileEx((const wchar_t *)nativePath.utf16(), FINDEX_INFO_LEVELS(infoLevel), &findData,
+                                         FINDEX_SEARCH_OPS(searchOps), 0, dwAdditionalFlags);
+        if (findFileHandle == INVALID_HANDLE_VALUE) {
+            if (nativePath.startsWith(QLatin1String("\\\\?\\UNC\\"))) {
+                QStringList parts = nativePath.split(QLatin1Char('\\'), QString::SkipEmptyParts);
+                if (parts.count() == 4 && QFileSystemEngine::uncListSharesOnServer(
+                        QLatin1String("\\\\") + parts.at(2), &uncShares)) {
+                    if (uncShares.isEmpty())
+                        return false; // No shares found in the server
+                    else
+                        uncFallback = true;
+                }
+            }
+        }
+    }
+    if (findFileHandle == INVALID_HANDLE_VALUE && !uncFallback)
+        return false;
+    // Retrieve the new file information.
+    if (!haveData) {
+        if (uncFallback) {
+            if (++uncShareIndex >= uncShares.count())
+                return false;
+        } else {
+            if (!FindNextFile(findFileHandle, &findData))
+                return false;
+        }
+    }
+    // Create the new file system entry & meta data.
+    if (uncFallback) {
+        fileEntry = QFileSystemEntry(dirPath + uncShares.at(uncShareIndex));
+        metaData.fillFromFileAttribute(FILE_ATTRIBUTE_DIRECTORY);
+        return true;
+    } else {
+        QString fileName = QString::fromWCharArray(findData.cFileName);
+        fileEntry = QFileSystemEntry(dirPath + fileName);
+        if (!fileName.endsWith(QLatin1String(".lnk"))) {
+            metaData.fillFromFindData(findData, true);
+        }
+        return true;
+    }
     return false;
 }