skia WIPjarred/canvas

1 files changed, 188 insertions, 0 deletions

diff --git a/src/deps/skia/include/core/SkData.h b/src/deps/skia/include/core/SkData.h
new file mode 100644
index 000000000..2a4b40d5f
--- /dev/null
+++ b/src/deps/skia/include/core/SkData.h
@@ -0,0 +1,188 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkData_DEFINED
+#define SkData_DEFINED
+
+#include <stdio.h>
+
+#include "include/core/SkRefCnt.h"
+
+class SkStream;
+
+/**
+ *  SkData holds an immutable data buffer. Not only is the data immutable,
+ *  but the actual ptr that is returned (by data() or bytes()) is guaranteed
+ *  to always be the same for the life of this instance.
+ */
+class SK_API SkData final : public SkNVRefCnt<SkData> {
+public:
+    /**
+     *  Returns the number of bytes stored.
+     */
+    size_t size() const { return fSize; }
+
+    bool isEmpty() const { return 0 == fSize; }
+
+    /**
+     *  Returns the ptr to the data.
+     */
+    const void* data() const { return fPtr; }
+
+    /**
+     *  Like data(), returns a read-only ptr into the data, but in this case
+     *  it is cast to uint8_t*, to make it easy to add an offset to it.
+     */
+    const uint8_t* bytes() const {
+        return reinterpret_cast<const uint8_t*>(fPtr);
+    }
+
+    /**
+     *  USE WITH CAUTION.
+     *  This call will assert that the refcnt is 1, as a precaution against modifying the
+     *  contents when another client/thread has access to the data.
+     */
+    void* writable_data() {
+        if (fSize) {
+            // only assert we're unique if we're not empty
+            SkASSERT(this->unique());
+        }
+        return const_cast<void*>(fPtr);
+    }
+
+    /**
+     *  Helper to copy a range of the data into a caller-provided buffer.
+     *  Returns the actual number of bytes copied, after clamping offset and
+     *  length to the size of the data. If buffer is NULL, it is ignored, and
+     *  only the computed number of bytes is returned.
+     */
+    size_t copyRange(size_t offset, size_t length, void* buffer) const;
+
+    /**
+     *  Returns true if these two objects have the same length and contents,
+     *  effectively returning 0 == memcmp(...)
+     */
+    bool equals(const SkData* other) const;
+
+    /**
+     *  Function that, if provided, will be called when the SkData goes out
+     *  of scope, allowing for custom allocation/freeing of the data's contents.
+     */
+    typedef void (*ReleaseProc)(const void* ptr, void* context);
+
+    /**
+     *  Create a new dataref by copying the specified data
+     */
+    static sk_sp<SkData> MakeWithCopy(const void* data, size_t length);
+
+
+    /**
+     *  Create a new data with uninitialized contents. The caller should call writable_data()
+     *  to write into the buffer, but this must be done before another ref() is made.
+     */
+    static sk_sp<SkData> MakeUninitialized(size_t length);
+
+    /**
+     *  Create a new data with zero-initialized contents. The caller should call writable_data()
+     *  to write into the buffer, but this must be done before another ref() is made.
+     */
+    static sk_sp<SkData> MakeZeroInitialized(size_t length);
+
+    /**
+     *  Create a new dataref by copying the specified c-string
+     *  (a null-terminated array of bytes). The returned SkData will have size()
+     *  equal to strlen(cstr) + 1. If cstr is NULL, it will be treated the same
+     *  as "".
+     */
+    static sk_sp<SkData> MakeWithCString(const char cstr[]);
+
+    /**
+     *  Create a new dataref, taking the ptr as is, and using the
+     *  releaseproc to free it. The proc may be NULL.
+     */
+    static sk_sp<SkData> MakeWithProc(const void* ptr, size_t length, ReleaseProc proc, void* ctx);
+
+    /**
+     *  Call this when the data parameter is already const and will outlive the lifetime of the
+     *  SkData. Suitable for with const globals.
+     */
+    static sk_sp<SkData> MakeWithoutCopy(const void* data, size_t length) {
+        return MakeWithProc(data, length, NoopReleaseProc, nullptr);
+    }
+
+    /**
+     *  Create a new dataref from a pointer allocated by malloc. The Data object
+     *  takes ownership of that allocation, and will handling calling sk_free.
+     */
+    static sk_sp<SkData> MakeFromMalloc(const void* data, size_t length);
+
+    /**
+     *  Create a new dataref the file with the specified path.
+     *  If the file cannot be opened, this returns NULL.
+     */
+    static sk_sp<SkData> MakeFromFileName(const char path[]);
+
+    /**
+     *  Create a new dataref from a stdio FILE.
+     *  This does not take ownership of the FILE, nor close it.
+     *  The caller is free to close the FILE at its convenience.
+     *  The FILE must be open for reading only.
+     *  Returns NULL on failure.
+     */
+    static sk_sp<SkData> MakeFromFILE(FILE* f);
+
+    /**
+     *  Create a new dataref from a file descriptor.
+     *  This does not take ownership of the file descriptor, nor close it.
+     *  The caller is free to close the file descriptor at its convenience.
+     *  The file descriptor must be open for reading only.
+     *  Returns NULL on failure.
+     */
+    static sk_sp<SkData> MakeFromFD(int fd);
+
+    /**
+     *  Attempt to read size bytes into a SkData. If the read succeeds, return the data,
+     *  else return NULL. Either way the stream's cursor may have been changed as a result
+     *  of calling read().
+     */
+    static sk_sp<SkData> MakeFromStream(SkStream*, size_t size);
+
+    /**
+     *  Create a new dataref using a subset of the data in the specified
+     *  src dataref.
+     */
+    static sk_sp<SkData> MakeSubset(const SkData* src, size_t offset, size_t length);
+
+    /**
+     *  Returns a new empty dataref (or a reference to a shared empty dataref).
+     *  New or shared, the caller must see that unref() is eventually called.
+     */
+    static sk_sp<SkData> MakeEmpty();
+
+private:
+    friend class SkNVRefCnt<SkData>;
+    ReleaseProc fReleaseProc;
+    void*       fReleaseProcContext;
+    const void* fPtr;
+    size_t      fSize;
+
+    SkData(const void* ptr, size_t size, ReleaseProc, void* context);
+    explicit SkData(size_t size);   // inplace new/delete
+    ~SkData();
+
+    // Ensure the unsized delete is called.
+    void operator delete(void* p);
+
+    // shared internal factory
+    static sk_sp<SkData> PrivateNewWithCopy(const void* srcOrNull, size_t length);
+
+    static void NoopReleaseProc(const void*, void*); // {}
+
+    using INHERITED = SkRefCnt;
+};
+
+#endif