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#include "il2cpp-config.h"
#if !IL2CPP_USE_GENERIC_MEMORY_MAPPED_FILE && IL2CPP_TARGET_WINDOWS
#include <map>
#include <limits>
#include "WindowsHelpers.h"
#include "os/MemoryMappedFile.h"
#include "utils/StringUtils.h"
namespace il2cpp
{
namespace os
{
static DWORD ConvertMappedFileAccessToWindowsPageAccess(MemoryMappedFileAccess access)
{
switch (access)
{
case MMAP_FILE_ACCESS_READ:
return PAGE_READONLY;
case MMAP_FILE_ACCESS_READ_WRITE:
return PAGE_READWRITE;
case MMAP_FILE_ACCESS_COPY_ON_WRITE:
return PAGE_WRITECOPY;
case MMAP_FILE_ACCESS_READ_EXECUTE:
return PAGE_EXECUTE_READ;
case MMAP_FILE_ACCESS_READ_WRITE_EXECUTE:
return PAGE_EXECUTE_READWRITE;
default:
IL2CPP_ASSERT("unknown MemoryMappedFileAccess");
}
return MMAP_FILE_ACCESS_READ;
}
static int ConvertMappedFileAccessToWindowsFileAccess(MemoryMappedFileAccess access)
{
switch (access)
{
case MMAP_FILE_ACCESS_READ:
return FILE_MAP_READ;
case MMAP_FILE_ACCESS_WRITE:
return FILE_MAP_WRITE;
case MMAP_FILE_ACCESS_READ_WRITE:
return FILE_MAP_READ | FILE_MAP_WRITE;
case MMAP_FILE_ACCESS_COPY_ON_WRITE:
return FILE_MAP_COPY;
case MMAP_FILE_ACCESS_READ_EXECUTE:
return FILE_MAP_EXECUTE | FILE_MAP_READ;
case MMAP_FILE_ACCESS_READ_WRITE_EXECUTE:
return FILE_MAP_EXECUTE | FILE_MAP_READ | FILE_MAP_WRITE;
default:
IL2CPP_ASSERT("unknown MemoryMappedFileAccess");
}
return MMAP_FILE_ACCESS_READ;
}
static MemoryMappedFileError ConvertWindowsErrorToMemoryMappedFileError(DWORD error, MemoryMappedFileError defaultError)
{
switch (error)
{
case ERROR_FILE_NOT_FOUND:
return FILE_NOT_FOUND;
case ERROR_FILE_EXISTS:
case ERROR_ALREADY_EXISTS:
return FILE_ALREADY_EXISTS;
case ERROR_ACCESS_DENIED:
return ACCESS_DENIED;
}
return defaultError;
}
FileHandle* MemoryMappedFile::Create(FileHandle* file, const char* mapName, int32_t mode, int64_t *capacity, MemoryMappedFileAccess access, int32_t options, MemoryMappedFileError* error)
{
HANDLE result = NULL;
HANDLE handle = file != NULL ? file : INVALID_HANDLE_VALUE;
if (handle == INVALID_HANDLE_VALUE)
{
if (*capacity <= 0 && mode != os::FILE_MODE_OPEN)
{
*error = CAPACITY_MUST_BE_POSITIVE;
return NULL;
}
#if IL2CPP_SIZEOF_VOID_P == 4
if (*capacity > UINT32_MAX)
{
*error = CAPACITY_LARGER_THAN_LOGICAL_ADDRESS_SPACE;
return NULL;
}
#endif
if (!(mode == FILE_MODE_CREATE_NEW || mode == FILE_MODE_OPEN_OR_CREATE || mode == FILE_MODE_OPEN))
{
*error = INVALID_FILE_MODE;
return NULL;
}
}
else
{
FILE_STANDARD_INFO info;
if (!GetFileInformationByHandleEx(handle, FileStandardInfo, &info, sizeof(FILE_STANDARD_INFO)))
{
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_OPEN);
return NULL;
}
if (*capacity == 0)
{
if (info.EndOfFile.QuadPart == 0)
{
*error = CAPACITY_SMALLER_THAN_FILE_SIZE;
return NULL;
}
}
else if (*capacity < info.EndOfFile.QuadPart)
{
*error = CAPACITY_SMALLER_THAN_FILE_SIZE;
return NULL;
}
}
UTF16String utf16MapNameString = mapName != NULL ? il2cpp::utils::StringUtils::Utf8ToUtf16(mapName) : UTF16String();
LPCWSTR utf16MapName = mapName != NULL ? utf16MapNameString.c_str() : NULL;
if (mode == FILE_MODE_CREATE_NEW || handle != INVALID_HANDLE_VALUE)
{
result = CreateFileMapping(handle, NULL, ConvertMappedFileAccessToWindowsPageAccess(access) | options, (DWORD)(((uint64_t)*capacity) >> 32), (DWORD)*capacity, utf16MapName);
if (result && GetLastError() == ERROR_ALREADY_EXISTS)
{
CloseHandle(result);
result = NULL;
*error = FILE_ALREADY_EXISTS;
}
else if (!result && GetLastError() != NO_ERROR)
{
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_OPEN);
}
}
else if (mode == FILE_MODE_OPEN || mode == FILE_MODE_OPEN_OR_CREATE && access == MMAP_FILE_ACCESS_WRITE)
{
result = OpenFileMappingW(ConvertMappedFileAccessToWindowsFileAccess(access), FALSE, utf16MapName);
if (!result)
{
if (mode == FILE_MODE_OPEN_OR_CREATE && GetLastError() == ERROR_FILE_NOT_FOUND)
{
*error = INVALID_FILE_MODE;
}
else
{
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_OPEN);
}
}
}
else if (mode == FILE_MODE_OPEN_OR_CREATE)
{
// This replicates how CoreFX does MemoryMappedFile.CreateOrOpen ().
/// Try to open the file if it exists -- this requires a bit more work. Loop until we can
/// either create or open a memory mapped file up to a timeout. CreateFileMapping may fail
/// if the file exists and we have non-null security attributes, in which case we need to
/// use OpenFileMapping. But, there exists a race condition because the memory mapped file
/// may have closed between the two calls -- hence the loop.
///
/// The retry/timeout logic increases the wait time each pass through the loop and times
/// out in approximately 1.4 minutes. If after retrying, a MMF handle still hasn't been opened,
/// throw an InvalidOperationException.
uint32_t waitRetries = 14; //((2^13)-1)*10ms == approximately 1.4mins
uint32_t waitSleep = 0;
while (waitRetries > 0)
{
result = CreateFileMapping(handle, NULL, ConvertMappedFileAccessToWindowsPageAccess(access) | options, (DWORD)(((uint64_t)*capacity) >> 32), (DWORD)*capacity, utf16MapName);
if (result)
break;
if (GetLastError() != ERROR_ACCESS_DENIED)
{
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_OPEN);
break;
}
result = OpenFileMapping(ConvertMappedFileAccessToWindowsFileAccess(access), FALSE, utf16MapName);
if (result)
break;
if (GetLastError() != ERROR_FILE_NOT_FOUND)
{
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_OPEN);
break;
}
// increase wait time
--waitRetries;
if (waitSleep == 0)
{
waitSleep = 10;
}
else
{
Sleep(waitSleep);
waitSleep *= 2;
}
}
if (!result)
*error = COULD_NOT_OPEN;
}
return (os::FileHandle*)result;
}
MemoryMappedFile::MemoryMappedFileHandle MemoryMappedFile::View(FileHandle* mappedFileHandle, int64_t* length, int64_t offset, MemoryMappedFileAccess access, int64_t* actualOffset, MemoryMappedFileError* error)
{
IL2CPP_ASSERT(actualOffset != NULL);
IL2CPP_ASSERT(offset <= std::numeric_limits<DWORD>::max());
IL2CPP_ASSERT(*length <= std::numeric_limits<DWORD>::max());
static DWORD allocationGranularity = 0;
if (allocationGranularity == 0)
{
SYSTEM_INFO info;
GetSystemInfo(&info);
allocationGranularity = info.dwAllocationGranularity;
}
int64_t extraMemNeeded = offset % allocationGranularity;
uint64_t newOffset = offset - extraMemNeeded;
uint64_t nativeSize = (*length != 0) ? *length + extraMemNeeded : 0;
*actualOffset = newOffset;
void* address = MapViewOfFile((HANDLE)mappedFileHandle, ConvertMappedFileAccessToWindowsFileAccess(access), (DWORD)(newOffset >> 32), (DWORD)newOffset, (SIZE_T)nativeSize);
if (address == NULL)
{
if (error != NULL)
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_MAP_MEMORY);
CloseHandle(mappedFileHandle);
return NULL;
}
// Query the view for its size and allocation type
MEMORY_BASIC_INFORMATION viewInfo;
VirtualQuery(address, &viewInfo, sizeof(MEMORY_BASIC_INFORMATION));
uint64_t viewSize = (uint64_t)viewInfo.RegionSize;
// Allocate the pages if we were using the MemoryMappedFileOptions.DelayAllocatePages option
// OR check if the allocated view size is smaller than the expected native size
// If multiple overlapping views are created over the file mapping object, the pages in a given region
// could have different attributes(MEM_RESERVE OR MEM_COMMIT) as MapViewOfFile preserves coherence between
// views created on a mapping object backed by same file.
// In which case, the viewSize will be smaller than nativeSize required and viewState could be MEM_COMMIT
// but more pages may need to be committed in the region.
// This is because, VirtualQuery function(that internally invokes VirtualQueryEx function) returns the attributes
// and size of the region of pages with matching attributes starting from base address.
// VirtualQueryEx: http://msdn.microsoft.com/en-us/library/windows/desktop/aa366907(v=vs.85).aspx
if (((viewInfo.State & MEM_RESERVE) != 0) || viewSize < (uint64_t)nativeSize)
{
void *tempAddress = VirtualAlloc(address, (SIZE_T)(nativeSize != 0 ? nativeSize : viewSize), MEM_COMMIT, ConvertMappedFileAccessToWindowsPageAccess(access));
if (!tempAddress)
{
if (error != NULL)
*error = ConvertWindowsErrorToMemoryMappedFileError(GetLastError(), COULD_NOT_MAP_MEMORY);
return NULL;
}
// again query the view for its new size
VirtualQuery(address, &viewInfo, sizeof(MEMORY_BASIC_INFORMATION));
viewSize = (uint64_t)viewInfo.RegionSize;
}
if (*length == 0)
*length = viewSize - extraMemNeeded;
return address;
}
void MemoryMappedFile::Flush(MemoryMappedFileHandle memoryMappedFileData, int64_t length)
{
BOOL success = FlushViewOfFile(memoryMappedFileData, (SIZE_T)length);
if (success)
return;
// This replicates how CoreFX does MemoryMappedView.Flush ().
// It is a known issue within the NTFS transaction log system that
// causes FlushViewOfFile to intermittently fail with ERROR_LOCK_VIOLATION
// As a workaround, we catch this particular error and retry the flush operation
// a few milliseconds later. If it does not work, we give it a few more tries with
// increasing intervals. Eventually, however, we need to give up. In ad-hoc tests
// this strategy successfully flushed the view after no more than 3 retries.
if (GetLastError() != ERROR_LOCK_VIOLATION)
// TODO: Propagate error to caller
return;
// These control the retry behaviour when lock violation errors occur during Flush:
const int MAX_FLUSH_WAITS = 15; // must be <=30
const int MAX_FLUSH_RETIRES_PER_WAIT = 20;
for (int w = 0; w < MAX_FLUSH_WAITS; w++)
{
int pause = (1 << w); // MaxFlushRetries should never be over 30
Sleep(pause);
for (int r = 0; r < MAX_FLUSH_RETIRES_PER_WAIT; r++)
{
if (FlushViewOfFile(memoryMappedFileData, (SIZE_T)length))
return;
if (GetLastError() != ERROR_LOCK_VIOLATION)
// TODO: Propagate error to caller
return;
SwitchToThread();
}
}
// We got to here, so there was no success
IL2CPP_ASSERT(false);
}
bool MemoryMappedFile::UnmapView(MemoryMappedFileHandle memoryMappedFileData, int64_t length)
{
if (memoryMappedFileData != NULL)
{
BOOL success = UnmapViewOfFile(memoryMappedFileData);
IL2CPP_ASSERT(success);
if (!success)
return false;
}
return true;
}
bool MemoryMappedFile::Close(FileHandle* file)
{
BOOL success = CloseHandle(file);
IL2CPP_ASSERT(success);
return success;
}
void MemoryMappedFile::ConfigureHandleInheritability(FileHandle* file, bool inheritability)
{
#if IL2CPP_TARGET_WINDOWS_DESKTOP
BOOL success = SetHandleInformation((HANDLE)file, HANDLE_FLAG_INHERIT, inheritability ? HANDLE_FLAG_INHERIT : 0);
IL2CPP_ASSERT(success);
#endif
}
bool MemoryMappedFile::OwnsDuplicatedFileHandle(FileHandle* file)
{
return true;
}
}
}
#endif