michael@0: /*
michael@0:  * Copyright 2013 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "SkOSFile.h"
michael@0: 
michael@0: #include "SkTFitsIn.h"
michael@0: 
michael@0: #include <io.h>
michael@0: #include <stdio.h>
michael@0: #include <sys/stat.h>
michael@0: 
michael@0: typedef struct {
michael@0:     ULONGLONG fVolume;
michael@0:     ULONGLONG fLsbSize;
michael@0:     ULONGLONG fMsbSize;
michael@0: } SkFILEID;
michael@0: 
michael@0: static bool sk_ino(SkFILE* f, SkFILEID* id) {
michael@0:     int fileno = _fileno((FILE*)f);
michael@0:     if (fileno < 0) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     HANDLE file = (HANDLE)_get_osfhandle(fileno);
michael@0:     if (INVALID_HANDLE_VALUE == file) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     //TODO: call GetFileInformationByHandleEx on Vista and later with FileIdInfo.
michael@0:     BY_HANDLE_FILE_INFORMATION info;
michael@0:     if (0 == GetFileInformationByHandle(file, &info)) {
michael@0:         return false;
michael@0:     }
michael@0:     id->fVolume = info.dwVolumeSerialNumber;
michael@0:     id->fLsbSize = info.nFileIndexLow + (((ULONGLONG)info.nFileIndexHigh) << 32);
michael@0:     id->fMsbSize = 0;
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool sk_fidentical(SkFILE* a, SkFILE* b) {
michael@0:     SkFILEID aID, bID;
michael@0:     return sk_ino(a, &aID) && sk_ino(b, &bID)
michael@0:            && aID.fLsbSize == bID.fLsbSize
michael@0:            && aID.fMsbSize == bID.fMsbSize
michael@0:            && aID.fVolume == bID.fVolume;
michael@0: }
michael@0: 
michael@0: class SkAutoNullKernelHandle : SkNoncopyable {
michael@0: public:
michael@0:     SkAutoNullKernelHandle(const HANDLE handle) : fHandle(handle) { }
michael@0:     ~SkAutoNullKernelHandle() { CloseHandle(fHandle); }
michael@0:     operator HANDLE() const { return fHandle; }
michael@0:     bool isValid() const { return NULL != fHandle; }
michael@0: private:
michael@0:     HANDLE fHandle;
michael@0: };
michael@0: typedef SkAutoNullKernelHandle SkAutoWinMMap;
michael@0: 
michael@0: void sk_fmunmap(const void* addr, size_t) {
michael@0:     UnmapViewOfFile(addr);
michael@0: }
michael@0: 
michael@0: void* sk_fdmmap(int fileno, size_t* length) {
michael@0:     HANDLE file = (HANDLE)_get_osfhandle(fileno);
michael@0:     if (INVALID_HANDLE_VALUE == file) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     LARGE_INTEGER fileSize;
michael@0:     if (0 == GetFileSizeEx(file, &fileSize)) {
michael@0:         //TODO: use SK_TRACEHR(GetLastError(), "Could not get file size.") to report.
michael@0:         return NULL;
michael@0:     }
michael@0:     if (!SkTFitsIn<size_t>(fileSize.QuadPart)) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     SkAutoWinMMap mmap(CreateFileMapping(file, NULL, PAGE_READONLY, 0, 0, NULL));
michael@0:     if (!mmap.isValid()) {
michael@0:         //TODO: use SK_TRACEHR(GetLastError(), "Could not create file mapping.") to report.
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     // Eventually call UnmapViewOfFile
michael@0:     void* addr = MapViewOfFile(mmap, FILE_MAP_READ, 0, 0, 0);
michael@0:     if (NULL == addr) {
michael@0:         //TODO: use SK_TRACEHR(GetLastError(), "Could not map view of file.") to report.
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     *length = static_cast<size_t>(fileSize.QuadPart);
michael@0:     return addr;
michael@0: }
michael@0: 
michael@0: int sk_fileno(SkFILE* f) {
michael@0:     return _fileno((FILE*)f);
michael@0: }
michael@0: 
michael@0: void* sk_fmmap(SkFILE* f, size_t* length) {
michael@0:     int fileno = sk_fileno(f);
michael@0:     if (fileno < 0) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     return sk_fdmmap(fileno, length);
michael@0: }