libwebp: update to 0.4.3

This commit imports libwebp 0.4.3, including AUTHORS, COPYING, ChangeLog,
NEWS, PATENTS, README and src directories. In src, only includes header
and source files.

The patches required to build it in Qt will follow in separate
commit(s).

Change-Id: I23ebfd69e47a468c91a9e9b109e9cb8ac63705d4
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: aavit <eirik.aavitsland@theqtcompany.com>

1 files changed, 40 insertions, 2 deletions

diff --git a/src/3rdparty/libwebp/src/utils/utils.h b/src/3rdparty/libwebp/src/utils/utils.h
index 8bdf0f0..f2c498a 100644
--- a/src/3rdparty/libwebp/src/utils/utils.h
+++ b/src/3rdparty/libwebp/src/utils/utils.h
@@ -35,10 +35,13 @@ extern "C" {
 // somewhere (like: malloc(num_pixels * sizeof(*something))). That's why this
 // safe malloc() borrows the signature from calloc(), pointing at the dangerous
 // underlying multiply involved.
-void* WebPSafeMalloc(uint64_t nmemb, size_t size);
+WEBP_EXTERN(void*) WebPSafeMalloc(uint64_t nmemb, size_t size);
 // Note that WebPSafeCalloc() expects the second argument type to be 'size_t'
 // in order to favor the "calloc(num_foo, sizeof(foo))" pattern.
-void* WebPSafeCalloc(uint64_t nmemb, size_t size);
+WEBP_EXTERN(void*) WebPSafeCalloc(uint64_t nmemb, size_t size);
+
+// Companion deallocation function to the above allocations.
+WEBP_EXTERN(void) WebPSafeFree(void* const ptr);
 
 //------------------------------------------------------------------------------
 // Reading/writing data.
@@ -74,6 +77,41 @@ static WEBP_INLINE void PutLE32(uint8_t* const data, uint32_t val) {
   PutLE16(data + 2, (int)(val >> 16));
 }
 
+// Returns (int)floor(log2(n)). n must be > 0.
+// use GNU builtins where available.
+#if defined(__GNUC__) && \
+    ((__GNUC__ == 3 && __GNUC_MINOR__ >= 4) || __GNUC__ >= 4)
+static WEBP_INLINE int BitsLog2Floor(uint32_t n) {
+  return 31 ^ __builtin_clz(n);
+}
+#elif defined(_MSC_VER) && _MSC_VER > 1310 && \
+      (defined(_M_X64) || defined(_M_IX86))
+#include <intrin.h>
+#pragma intrinsic(_BitScanReverse)
+
+static WEBP_INLINE int BitsLog2Floor(uint32_t n) {
+  uint32_t first_set_bit;
+  _BitScanReverse(&first_set_bit, n);
+  return first_set_bit;
+}
+#else
+static WEBP_INLINE int BitsLog2Floor(uint32_t n) {
+  int log = 0;
+  uint32_t value = n;
+  int i;
+
+  for (i = 4; i >= 0; --i) {
+    const int shift = (1 << i);
+    const uint32_t x = value >> shift;
+    if (x != 0) {
+      value = x;
+      log += shift;
+    }
+  }
+  return log;
+}
+#endif
+
 //------------------------------------------------------------------------------
 
 #ifdef __cplusplus