Move MMap to SkData.

src/core/SkData.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkData.h"
 #include "SkFlattenableBuffers.h"
+#include "SkOSFile.h"
 
 #if SK_MMAP_SUPPORT
     #include <unistd.h>
     #include <sys/mman.h>
     #include <fcntl.h>
     #include <errno.h>
+    #include <unistd.h>
+#else
+    #include <io.h>
 #endif
 
 SK_DEFINE_INST_COUNT(SkData)
 
 SkData::SkData(const void* ptr, size_t size, ReleaseProc proc, void* context) {
     fPtr = ptr;
     fSize = size;
     fReleaseProc = proc;
     fReleaseProcContext = context;
 }
@@ skipping 61 matching lines @@
                             ReleaseProc proc, void* context) {
     return new SkData(data, length, proc, context);
 }
 
 // assumes context is a SkData
 static void sk_dataref_releaseproc(const void*, size_t, void* context) {
     SkData* src = reinterpret_cast<SkData*>(context);
     src->unref();
 }
 
+#if SK_MMAP_SUPPORT
+
+static void sk_munmap_releaseproc(const void* addr, size_t length, void*) {
+    munmap(const_cast<void*>(addr), length);
+}
+
+SkData* SkData::NewFromFILE(SkFILE* f) {
+    size_t size = sk_fgetsize(f);
+    if (0 == size) {
+        return NULL;
+    }
+
+    int fd = fileno((FILE*)f);
+    if (fd < 0) {
+        return NULL;
+    }
+
+    void* addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0);
+    if (MAP_FAILED == addr) {
+        return NULL;
+    }
+
+    return SkData::NewWithProc(addr, size, sk_munmap_releaseproc, NULL);
+}
+
+#elif SK_BUILD_FOR_WIN32
+
+template <typename HandleType, HandleType InvalidValue, BOOL (WINAPI * Close)(HandleType)>
+class SkAutoTHandle : SkNoncopyable {
+public:
+    SkAutoTHandle(HandleType handle) : fHandle(handle) { }
+    ~SkAutoTHandle() { Close(fHandle); }
+    operator HandleType() { return fHandle; }
+    bool isValid() { return InvalidValue != fHandle; }
+private:
+    HandleType fHandle;
+};
+typedef SkAutoTHandle<HANDLE, INVALID_HANDLE_VALUE, CloseHandle> SkAutoWinFile;
+typedef SkAutoTHandle<HANDLE, NULL, CloseHandle> SkAutoWinMMap;
+
+static void sk_munmap_releaseproc(const void* addr, size_t, void*) {
+    UnmapViewOfFile(addr);
+}
+
+SkData* SkData::NewFromFILE(SkFILE* f) {
+    size_t size = sk_fgetsize(f);
+    if (0 == size) {
+        return NULL;
+    }
+
+    int fileno = _fileno((FILE*)f);
+    if (fileno < 0) {
+        return NULL;
+    }
+
+    HANDLE file = (HANDLE)_get_osfhandle(fileno);
+    if (INVALID_HANDLE_VALUE == file) {
+        return NULL;
+    }
+
+    SkAutoWinMMap mmap(CreateFileMapping(file, NULL, PAGE_READONLY, 0, 0, NULL));
+    if (!mmap.isValid()) {
+        //TODO: use SK_TRACEHR(GetLastError(), "Could not create file mapping.") to report.
+        return NULL;
+    }
+
+    // Eventually call UnmapViewOfFile
+    void* addr = MapViewOfFile(mmap, FILE_MAP_READ, 0, 0, 0);
+    if (NULL == addr) {
+        //TODO: use SK_TRACEHR(GetLastError(), "Could not map view of file.") to report.
+        return NULL;
+    }
+
+    return SkData::NewWithProc(addr, size, sk_munmap_releaseproc, NULL);
+}
+
+#else
+
+SkData* SkData::NewFromFILE(SkFILE* f) {
+    return NULL;
+}
+
+#endif
+
 SkData* SkData::NewSubset(const SkData* src, size_t offset, size_t length) {
     /*
         We could, if we wanted/need to, just make a deep copy of src's data,
         rather than referencing it. This would duplicate the storage (of the
         subset amount) but would possibly allow src to go out of scope sooner.
      */
 
     size_t available = src->size();
     if (offset >= available || 0 == length) {
         return SkData::NewEmpty();
@@ skipping 13 matching lines @@
     size_t size;
     if (NULL == cstr) {
         cstr = "";
         size = 1;
     } else {
         size = strlen(cstr) + 1;
     }
     return NewWithCopy(cstr, size);
 }
 
-#if SK_MMAP_SUPPORT
-static void sk_munmap_releaseproc(const void* addr, size_t length, void*) {
-    munmap(const_cast<void*>(addr), length);
-}
-
-SkData* SkData::NewFromMMap(const void* addr, size_t length) {
-    return SkNEW_ARGS(SkData, (addr, length, sk_munmap_releaseproc, NULL));
-}
-#else
-SkData* SkData::NewFromMMap(const void* addr, size_t length) {
-    return NULL;
-}
-#endif
-
 ///////////////////////////////////////////////////////////////////////////////
 
 void SkData::flatten(SkFlattenableWriteBuffer& buffer) const {
     buffer.writeByteArray(fPtr, fSize);
 }
 
 SkData::SkData(SkFlattenableReadBuffer& buffer) {
     fSize = buffer.getArrayCount();
     fReleaseProcContext = NULL;
 
@@ skipping 160 matching lines @@
 }
 
 SkDataSet* SkDataSet::NewEmpty() {
     static SkDataSet* gEmptySet;
     if (NULL == gEmptySet) {
         gEmptySet = SkNEW_ARGS(SkDataSet, (NULL, 0));
     }
     gEmptySet->ref();
     return gEmptySet;
 }