Restore old CopyMem as CopyMemC

CopyMemC cos CONST Src

Reverts 6b9dae0bef

Signed-off-by: Callum Farmer <gmbr3@opensuse.org>

inc/efilib.h

@@ -303,6 +303,13 @@ CopyMem (
     IN UINTN    len
     );
 
+VOID EFIAPI
+CopyMemC (
+    IN VOID     *Dest,
+    IN CONST VOID     *Src,
+    IN UINTN    len
+    );
+
 INTN
 CompareMem (
     IN CONST VOID     *Dest,

inc/efirtlib.h

@@ -62,6 +62,15 @@ RtCopyMem (
     IN UINTN    len
     );
 
+VOID
+EFIAPI
+RUNTIMEFUNCTION
+RtCopyMemC (
+    IN VOID     *Dest,
+    IN CONST VOID     *Src,
+    IN UINTN    len
+    );
+
 INTN
 RUNTIMEFUNCTION
 RtCompareMem (

lib/misc.c

@@ -118,6 +118,16 @@ CopyMem (
     RtCopyMem (Dest, Src, len);
 }
 
+VOID EFIAPI
+CopyMemC (
+    IN VOID     *Dest,
+    IN CONST VOID     *Src,
+    IN UINTN    len
+    )
+{
+    RtCopyMemC (Dest, Src, len);
+}
+
 INTN
 CompareMem (
     IN CONST VOID     *Dest,

lib/runtime/efirtlib.c

@@ -88,6 +88,30 @@ RtCopyMem (
     }
 }
 
+#ifndef __GNUC__
+#pragma RUNTIME_CODE(RtCopyMemC)
+#endif
+VOID
+EFIAPI
+RUNTIMEFUNCTION
+RtCopyMemC (
+    IN VOID        *Dest,
+    IN CONST VOID  *Src,
+    IN UINTN       len
+    )
+{
+    CHAR8 *d = (CHAR8*)Dest;
+    CONST CHAR8 *s = (CONST CHAR8*)Src;
+
+    if (d == NULL || s == NULL || s == d)
+        return;
+
+    /* CONST Src: UB if Src and Dest overlap */
+
+    while (len--) 
+        *d++ = *s++;
+}
+
 #ifndef __GNUC__
 #pragma RUNTIME_CODE(RtCompareMem)
 #endif

lib/runtime/rtstr.c

@@ -69,13 +69,11 @@ RtStrnCpy (
     )
 // copy strings
 {
-    CHAR16 CopySrc = *Src;
-    CHAR16 *PCopySrc = &CopySrc;
     
     UINTN Size = RtStrnLen(Src, Len);
     if (Size != Len)
         RtSetMem(Dest + Size, (Len - Size) * sizeof(CHAR16), '\0');
-    RtCopyMem(Dest, PCopySrc, Size * sizeof(CHAR16));
+    RtCopyMemC(Dest, Src, Size * sizeof(CHAR16));
 }
 
 #ifndef __GNUC__
@@ -108,13 +106,11 @@ RtStpnCpy (
     )
 // copy strings
 {
-    CHAR16 CopySrc = *Src;
-    CHAR16 *PCopySrc = &CopySrc;
     
     UINTN Size = RtStrnLen(Src, Len);
     if (Size != Len)
         RtSetMem(Dest + Size, (Len - Size) * sizeof(CHAR16), '\0');
-    RtCopyMem(Dest, PCopySrc, Size * sizeof(CHAR16));
+    RtCopyMemC(Dest, Src, Size * sizeof(CHAR16));
     return Dest + Size;
 }
 
@@ -143,12 +139,10 @@ RtStrnCat (
     )
 {
     UINTN DestSize, Size;
-    CHAR16 CopySrc = *Src;
-    CHAR16 *PCopySrc = &CopySrc;
 
     DestSize = RtStrLen(Dest);
     Size = RtStrnLen(Src, Len);
-    RtCopyMem(Dest + DestSize, PCopySrc, Size * sizeof(CHAR16));
+    RtCopyMemC(Dest + DestSize, Src, Size * sizeof(CHAR16));
     Dest[DestSize + Size] = '\0';
 }
 

lib/str.c

@@ -201,13 +201,11 @@ StrDuplicate (
 {
     CHAR16      *Dest;
     UINTN       Size;
-    CHAR16      CopySrc = *Src;
-    CHAR16      *PCopySrc = &CopySrc;
 
     Size = StrSize(Src);
     Dest = AllocatePool (Size);
     if (Dest) {
-        CopyMem (Dest, PCopySrc, Size);
+        CopyMemC (Dest, Src, Size);
     }
     return Dest;
 }