MdePkg/BaseSafeIntLib: fix undefined behavior in SafeInt64Add()

[mirror_edk2.git] / MdePkg / Library / UefiMemoryLib / MemLibGeneric.c

diff --git a/MdePkg/Library/UefiMemoryLib/MemLibGeneric.c b/MdePkg/Library/UefiMemoryLib/MemLibGeneric.c
index 2780cbfd9bad9db275c42b97eac3f6b794cc6d85..f1efdbb413d1dc10971b039e5488f952c586c1bc 100644 (file)
--- a/MdePkg/Library/UefiMemoryLib/MemLibGeneric.c
+++ b/MdePkg/Library/UefiMemoryLib/MemLibGeneric.c
@@ -6,7 +6,7 @@
     PeiMemoryLib\r
     UefiMemoryLib\r
 \r
-  Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>\r
+  Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>\r
   This program and the accompanying materials\r
   are licensed and made available under the terms and conditions of the BSD License\r
   which accompanies this distribution.  The full text of the license may be found at\r
@@ -37,9 +37,9 @@ InternalMemSetMem16 (
   IN      UINT16                    Value\r
   )\r
 {\r
-  do {\r
-    ((UINT16*)Buffer)[--Length] = Value;\r
-  } while (Length != 0);\r
+  for (; Length != 0; Length--) {\r
+    ((UINT16*)Buffer)[Length - 1] = Value;\r
+  }\r
   return Buffer;\r
 }\r
 \r
@@ -61,9 +61,9 @@ InternalMemSetMem32 (
   IN      UINT32                    Value\r
   )\r
 {\r
-  do {\r
-    ((UINT32*)Buffer)[--Length] = Value;\r
-  } while (Length != 0);\r
+  for (; Length != 0; Length--) {\r
+    ((UINT32*)Buffer)[Length - 1] = Value;\r
+  }\r
   return Buffer;\r
 }\r
 \r
@@ -85,9 +85,9 @@ InternalMemSetMem64 (
   IN      UINT64                    Value\r
   )\r
 {\r
-  do {\r
-    ((UINT64*)Buffer)[--Length] = Value;\r
-  } while (Length != 0);\r
+  for (; Length != 0; Length--) {\r
+    ((UINT64*)Buffer)[Length - 1] = Value;\r
+  }\r
   return Buffer;\r
 }\r
 \r
@@ -163,7 +163,7 @@ InternalMemScanMem8 (
   Pointer = (CONST UINT8*)Buffer;\r
   do {\r
     if (*(Pointer++) == Value) {\r
-      return Pointer;\r
+      return --Pointer;\r
     }\r
   } while (--Length != 0);\r
   return NULL;\r
@@ -193,7 +193,7 @@ InternalMemScanMem16 (
   Pointer = (CONST UINT16*)Buffer;\r
   do {\r
     if (*(Pointer++) == Value) {\r
-      return Pointer;\r
+      return --Pointer;\r
     }\r
   } while (--Length != 0);\r
   return NULL;\r
@@ -223,7 +223,7 @@ InternalMemScanMem32 (
   Pointer = (CONST UINT32*)Buffer;\r
   do {\r
     if (*(Pointer++) == Value) {\r
-      return Pointer;\r
+      return --Pointer;\r
     }\r
   } while (--Length != 0);\r
   return NULL;\r
@@ -253,8 +253,37 @@ InternalMemScanMem64 (
   Pointer = (CONST UINT64*)Buffer;\r
   do {\r
     if (*(Pointer++) == Value) {\r
-      return Pointer;\r
+      return --Pointer;\r
     }\r
   } while (--Length != 0);\r
   return NULL;\r
 }\r
+\r
+/**\r
+  Checks whether the contents of a buffer are all zeros.\r
+\r
+  @param  Buffer  The pointer to the buffer to be checked.\r
+  @param  Length  The size of the buffer (in bytes) to be checked.\r
+\r
+  @retval TRUE    Contents of the buffer are all zeros.\r
+  @retval FALSE   Contents of the buffer are not all zeros.\r
+\r
+**/\r
+BOOLEAN\r
+EFIAPI\r
+InternalMemIsZeroBuffer (\r
+  IN CONST VOID  *Buffer,\r
+  IN UINTN       Length\r
+  )\r
+{\r
+  CONST UINT8 *BufferData;\r
+  UINTN       Index;\r
+\r
+  BufferData = Buffer;\r
+  for (Index = 0; Index < Length; Index++) {\r
+    if (BufferData[Index] != 0) {\r
+      return FALSE;\r
+    }\r
+  }\r
+  return TRUE;\r
+}\r