Cleanup most usages of Windows file mapping

src/coreclr/ilasm/asmparse.h

@@ -7,6 +7,8 @@
 #define asmparse_h
 
 #include <stdio.h>		// for FILE
+#include <winwrap.h>
+#include <dn-memmap.h>
 
 #include "assembler.h"	// for ErrorReporter Labels
 //class Assembler;
@@ -95,9 +97,8 @@ class MappedFileStream : public ReadStream {
 public:
     MappedFileStream(_In_ __nullterminated WCHAR* wFileName)
         : m_fileNameUtf8(NULL)
-        , m_hFile(INVALID_HANDLE_VALUE)
+        , m_File(nullptr)
         , m_FileSize(0)
-        , m_hMapFile(NULL)
     {
         m_pStart = open(wFileName);
         m_pCurr = m_pStart;
@@ -112,20 +113,8 @@ class MappedFileStream : public ReadStream {
     }
     ~MappedFileStream()
     {
-        if (m_hFile != INVALID_HANDLE_VALUE)
-        {
-            if (m_pStart)
-                UnmapViewOfFile((void*)m_pStart);
-            if (m_hMapFile)
-                CloseHandle(m_hMapFile);
-            CloseHandle(m_hFile);
-
-            m_pStart = NULL;
-            m_hMapFile = NULL;
-            m_hFile = INVALID_HANDLE_VALUE;
-            m_FileSize = 0;
-        }
-
+        if (m_File)
+            delete m_File;
         if (m_fileNameUtf8 != NULL)
             delete [] m_fileNameUtf8;
     }
@@ -171,37 +160,27 @@ class MappedFileStream : public ReadStream {
 	}
 
 private:
-    char* map_file()
-    {
-        DWORD dwFileSizeLow;
-
-        dwFileSizeLow = GetFileSize( m_hFile, NULL);
-        if (dwFileSizeLow == INVALID_FILE_SIZE)
-            return NULL;
-        m_FileSize = dwFileSizeLow;
-
-        // No difference between A and W in this case: last param (LPCTSTR) is NULL
-        m_hMapFile = CreateFileMapping(m_hFile, NULL, PAGE_READONLY, 0, 0, NULL);
-        if (m_hMapFile == NULL)
-            return NULL;
-
-        return (char*)(HMODULE) MapViewOfFile(m_hMapFile, FILE_MAP_READ, 0, 0, 0);
-    }
     char* open(const WCHAR* moduleName)
     {
         _ASSERTE(moduleName);
         if (!moduleName)
             return NULL;
 
-        m_hFile = WszCreateFile(moduleName, GENERIC_READ, FILE_SHARE_READ,
-                             0, OPEN_EXISTING, 0, 0);
-        return (m_hFile == INVALID_HANDLE_VALUE) ? NULL : map_file();
+        m_File = CreateMappedFile(moduleName);
+        if (m_File == nullptr)
+        {
+            m_File = nullptr;
+            m_FileSize = 0;
+            return nullptr;
+        }
+
+        m_FileSize = (DWORD)m_File->Size();
+        return (char*)m_File->Address();
     }
 
     char*	m_fileNameUtf8; // FileName (for error reporting)
-    HANDLE  m_hFile;                 // File we are reading from
+    MemoryMappedFile* m_File; // File we are reading from
     DWORD   m_FileSize;
-    HANDLE  m_hMapFile;
     char*   m_pStart;
     char*   m_pEnd;
     char*   m_pCurr;

src/coreclr/ildasm/ceeload.cpp

@@ -17,9 +17,8 @@
 /*************************************************************************************/
 PELoader::PELoader()
 {
-    m_hFile = NULL;
+    m_File = nullptr;
     m_hMod = NULL;
-    m_hMapFile = NULL;
     m_pNT64 = NULL;
     m_bIsPE32 = FALSE;
     m_FileSize = m_FileSizeAligned = 0;
@@ -30,91 +29,31 @@ PELoader::~PELoader()
 
     m_hMod = NULL;
     m_pNT64 = NULL;
-    // If we have an hFile then we opened this file ourselves!
-    // If we do not then this file was loaded by the OS and the OS will
-    // close it for us.
-    if (m_hFile)
-        this->close();
 }
 
 /*************************************************************************************/
 /*************************************************************************************/
 void PELoader::close()
 {
-
-    // _ASSERTE(m_hFile != NULL);
-    if (m_hFile)
-    {
-        if (m_hMod)
-            UnmapViewOfFile((void*)m_hMod);
-        if (m_hMapFile)
-            CloseHandle(m_hMapFile);
-        CloseHandle(m_hFile);
-
-        m_hMod = NULL;
-        m_hMapFile = NULL;
-        m_hFile = NULL;
-        m_FileSize = m_FileSizeAligned = 0;
-    }
-}
-
-
-BOOL PELoader::open(LPCSTR moduleName)
-{
-    HMODULE newhMod = NULL;
-    DWORD dwFileSizeLow;
-
-    _ASSERTE(moduleName);
-    if (!moduleName)
-        return FALSE;
-
-
-    m_hFile = CreateFileA(moduleName, GENERIC_READ, FILE_SHARE_READ,
-                         0, OPEN_EXISTING, 0, 0);
-    if (m_hFile == INVALID_HANDLE_VALUE)
-        return FALSE;
-
-    dwFileSizeLow = GetFileSize( m_hFile, NULL);
-    if (dwFileSizeLow == INVALID_FILE_SIZE)
-        return FALSE;
-    m_FileSize = dwFileSizeLow;
-
-    m_hMapFile = CreateFileMapping(m_hFile, NULL, PAGE_READONLY, 0, 0, NULL);
-    if (m_hMapFile == NULL)
-        return FALSE;
-
-    newhMod = (HMODULE) MapViewOfFile(m_hMapFile, FILE_MAP_READ, 0, 0, 0);
-    if (newhMod == NULL)
-        return FALSE;
-   return open(newhMod);
+    delete m_File;
+    m_File = nullptr;
 }
 
 BOOL PELoader::open(const WCHAR* moduleName)
 {
     HMODULE newhMod = NULL;
-    DWORD dwFileSizeLow;
 
     _ASSERTE(moduleName);
     if (!moduleName)
         return FALSE;
 
-    m_hFile = WszCreateFile(moduleName, GENERIC_READ, FILE_SHARE_READ,
-                         0, OPEN_EXISTING, 0, 0);
-    if (m_hFile == INVALID_HANDLE_VALUE)
+    m_File = CreateMappedFile(moduleName);
+    if (m_File == nullptr)
         return FALSE;
 
-    dwFileSizeLow = GetFileSize( m_hFile, NULL);
-    if (dwFileSizeLow == INVALID_FILE_SIZE)
-        return FALSE;
-    m_FileSize = dwFileSizeLow;
+    m_FileSize = m_File->Size();
 
-    m_hMapFile = CreateFileMapping(m_hFile, NULL, PAGE_READONLY, 0, 0, NULL);
-    if (m_hMapFile == NULL)
-        return FALSE;
-
-    newhMod = (HMODULE) MapViewOfFile(m_hMapFile, FILE_MAP_READ, 0, 0, 0);
-    if (newhMod == NULL)
-        return FALSE;
+    newhMod = (HMODULE)m_File->Address();
    return open(newhMod);
 }
 

src/coreclr/ildasm/ceeload.h

@@ -35,8 +35,7 @@ class PELoader {
   protected:
 
     HMODULE m_hMod;
-    HANDLE m_hFile;
-    HANDLE m_hMapFile;
+    MemoryMappedFile* m_File;
     BOOL   m_bIsPE32;
     size_t m_FileSize;
     size_t m_FileSizeAligned;
@@ -54,7 +53,6 @@ class PELoader {
 
     PELoader();
     ~PELoader();
-    BOOL open(const char* moduleNameIn);
     BOOL open(const WCHAR* moduleNameIn);
     BOOL open(HMODULE hMod);
     BOOL getCOMHeader(IMAGE_COR20_HEADER **ppCorHeader);
@@ -69,7 +67,7 @@ class PELoader {
     inline DWORD Signature() { return m_pNT32->Signature; };
     inline BYTE*  base() { return (BYTE*) m_hMod; };
     inline HMODULE getHModule() { return  m_hMod; };
-    inline HANDLE getHFile()	{ return  m_hFile; } ;
+    inline uint32_t getFileSize() { return (uint32_t)m_FileSize; };
 };
 
 #endif // CEELoad_H

src/coreclr/ildasm/dasm.cpp

@@ -5837,7 +5837,7 @@ void DumpStatistics(IMAGE_COR20_HEADER *CORHeader, void* GUICookie)
     TableSeenReset();
     metaSize = 0;
 
-    sprintf_s(szString,SZSTRING_SIZE,"// File size            : %d", fileSize = SafeGetFileSize(g_pPELoader->getHFile(), NULL));
+    sprintf_s(szString,SZSTRING_SIZE,"// File size            : %u", fileSize = g_pPELoader->getFileSize());
     printLine(GUICookie,szStr);
 
     if (g_pPELoader->IsPE32())

src/coreclr/ildasm/ildasmpch.h

@@ -13,7 +13,8 @@
 #include <string.h>
 #include <limits.h>
 #include <algorithm>
-#include "dn-stdio.h"
+#include <dn-stdio.h>
+#include <dn-memmap.h>
 
 using std::min;
 using std::max;

src/coreclr/inc/longfilepathwrappers.h

@@ -5,6 +5,8 @@
 #define _WIN_PATH_APIS_WRAPPER_
 class SString;
 
+#include <dn-memmap.h>
+
 #ifdef HOST_WINDOWS
 
 HMODULE
@@ -27,6 +29,8 @@ CreateFileWrapper(
 
 int u16_fopen_wrapper(FILE** stream, const WCHAR* filename, const WCHAR* mode);
 
+MemoryMappedFile* CreateMappedFileWrapper(const WCHAR* filename);
+
 BOOL
 CopyFileExWrapper(
     _In_        LPCWSTR lpExistingFileName,

src/coreclr/inc/winwrap.h

@@ -43,10 +43,12 @@
 #define WszLoadLibrary         LoadLibraryExWrapper
 #define WszCreateFile          CreateFileWrapper
 #define fopen_lp               u16_fopen_wrapper
+#define CreateMappedFile       CreateMappedFileWrapper
 #else // HOST_WINDOWS
 #define WszLoadLibrary         LoadLibraryExW
 #define WszCreateFile          CreateFileW
 #define fopen_lp               u16_fopen_s
+#define CreateMappedFile       MemoryMappedFile::Open
 #endif // HOST_WINDOWS
 
 //APIS which have a buffer as an out parameter