Make bcopy() emulation of memmove() work properly.

ChangeLog

@@ -148,6 +148,13 @@ end of its group during the parse process, but without another setting such as
 (?m) the compile phase got it right.) This bug was introduced by the
 refactoring in release 10.23.
 
+33. PCRE2 uses bcopy() if available when memmove() is not, and it used just to 
+define memmove() as function call to bcopy(). This hasn't been tested for a
+long time because in pcre2test the result of memmove() was being used, whereas 
+bcopy() doesn't return a result. This feature is now refactored always to call 
+an emulation function when there is no memmove(). The emulation makes use of 
+bcopy() when available.
+      
 
 Version 10.31 12-February-2018
 ------------------------------

src/pcre2_compile.c

@@ -5655,7 +5655,7 @@ for (;; pptr++)
       if (class_has_8bitchar > 0)
         {
         *code++ |= XCL_MAP;
-        memmove(code + (32 / sizeof(PCRE2_UCHAR)), code,
+        (void)memmove(code + (32 / sizeof(PCRE2_UCHAR)), code,
           CU2BYTES(class_uchardata - code));
         if (negate_class && !xclass_has_prop)
           for (i = 0; i < 32; i++) classbits[i] = ~classbits[i];
@@ -6602,7 +6602,7 @@ for (;; pptr++)
 
       /* Wrap the recursion call in OP_BRA brackets. */
 
-      memmove(previous + 1 + LINK_SIZE, previous, CU2BYTES(1 + LINK_SIZE));
+      (void)memmove(previous + 1 + LINK_SIZE, previous, CU2BYTES(1 + LINK_SIZE));
       op_previous = *previous = OP_BRA;
       PUT(previous, 1, 2 + 2*LINK_SIZE);
       previous[2 + 2*LINK_SIZE] = OP_KET;
@@ -6682,7 +6682,7 @@ for (;; pptr++)
 
           if (repeat_max <= 1 || repeat_max == REPEAT_UNLIMITED)
             {
-            memmove(previous + 1, previous, CU2BYTES(len));
+            (void)memmove(previous + 1, previous, CU2BYTES(len));
             code++;
             if (repeat_max == 0)
               {
@@ -6703,7 +6703,7 @@ for (;; pptr++)
           else
             {
             int linkoffset;
-            memmove(previous + 2 + LINK_SIZE, previous, CU2BYTES(len));
+            (void)memmove(previous + 2 + LINK_SIZE, previous, CU2BYTES(len));
             code += 2 + LINK_SIZE;
             *previous++ = OP_BRAZERO + repeat_type;
             *previous++ = OP_BRA;
@@ -6904,7 +6904,7 @@ for (;; pptr++)
               if (*bracode == OP_COND || *bracode == OP_SCOND)
                 {
                 int nlen = (int)(code - bracode);
-                memmove(bracode + 1 + LINK_SIZE, bracode, CU2BYTES(nlen));
+                (void)memmove(bracode + 1 + LINK_SIZE, bracode, CU2BYTES(nlen));
                 code += 1 + LINK_SIZE;
                 nlen += 1 + LINK_SIZE;
                 *bracode = (*bracode == OP_COND)? OP_BRAPOS : OP_SBRAPOS;
@@ -7175,7 +7175,7 @@ for (;; pptr++)
 
         else
           {
-          memmove(tempcode + 1 + LINK_SIZE, tempcode, CU2BYTES(len));
+          (void)memmove(tempcode + 1 + LINK_SIZE, tempcode, CU2BYTES(len));
           code += 1 + LINK_SIZE;
           len += 1 + LINK_SIZE;
           tempcode[0] = OP_ONCE;
@@ -7715,7 +7715,7 @@ for (;;)
       {
       if (cb->open_caps->flag)
         {
-        memmove(start_bracket + 1 + LINK_SIZE, start_bracket,
+        (void)memmove(start_bracket + 1 + LINK_SIZE, start_bracket,
           CU2BYTES(code - start_bracket));
         *start_bracket = OP_ONCE;
         code += 1 + LINK_SIZE;
@@ -8315,7 +8315,7 @@ for (i = 0; i < tablecount; i++)
 
   if (crc < 0)
     {
-    memmove(slot + cb->name_entry_size, slot,
+    (void)memmove(slot + cb->name_entry_size, slot,
       CU2BYTES((tablecount - i) * cb->name_entry_size));
     break;
     }

src/pcre2_dfa_match.c

@@ -875,7 +875,7 @@ for (;;)
             else if (match_count > 0 && ++match_count * 2 > (int)offsetcount)
               match_count = 0;
           count = ((match_count == 0)? (int)offsetcount : match_count * 2) - 2;
-          if (count > 0) memmove(offsets + 2, offsets,
+          if (count > 0) (void)memmove(offsets + 2, offsets,
             (size_t)count * sizeof(PCRE2_SIZE));
           if (offsetcount >= 2)
             {

src/pcre2_internal.h

@@ -165,6 +165,16 @@ by "configure". */
 #define INT64_OR_DOUBLE double
 #endif
 
+/* External (in the C sense) functions and tables that are private to the
+libraries are always referenced using the PRIV macro. This makes it possible
+for pcre2test.c to include some of the source files from the libraries using a
+different PRIV definition to avoid name clashes. It also makes it clear in the
+code that a non-static object is being referenced. */
+
+#ifndef PRIV
+#define PRIV(name) _pcre2_##name
+#endif
+
 /* When compiling for use with the Virtual Pascal compiler, these functions
 need to have their names changed. PCRE2 must be compiled with the -DVPCOMPAT
 option on the command line. */
@@ -178,50 +188,15 @@ option on the command line. */
 #define memset(s,c,n)    _memset(s,c,n)
 #else  /* VPCOMPAT */
 
-/* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
+/* Otherwise, to cope with SunOS4 and other systems that lack memmove(), define
-define a macro for memmove() if HAVE_MEMMOVE is false, provided that HAVE_BCOPY
+a macro that calls an emulating function. */
-is set. Otherwise, include an emulating function for those systems that have
-neither (there some non-Unix environments where this is the case). */
 
 #ifndef HAVE_MEMMOVE
-#undef  memmove        /* some systems may have a macro */
+#undef  memmove          /* Some systems may have a macro */
-#ifdef HAVE_BCOPY
+#define memmove(a, b, c) PRIV(memmove)(a, b, c)
-#define memmove(a, b, c) bcopy(b, a, c)
-#else  /* HAVE_BCOPY */
-static void *
-pcre2_memmove(void *d, const void *s, size_t n)
-{
-size_t i;
-unsigned char *dest = (unsigned char *)d;
-const unsigned char *src = (const unsigned char *)s;
-if (dest > src)
-  {
-  dest += n;
-  src += n;
-  for (i = 0; i < n; ++i) *(--dest) = *(--src);
-  return (void *)dest;
-  }
-else
-  {
-  for (i = 0; i < n; ++i) *dest++ = *src++;
-  return (void *)(dest - n);
-  }
-}
-#define memmove(a, b, c) pcre2_memmove(a, b, c)
-#endif   /* not HAVE_BCOPY */
 #endif   /* not HAVE_MEMMOVE */
 #endif   /* not VPCOMPAT */
 
-/* External (in the C sense) functions and tables that are private to the
-libraries are always referenced using the PRIV macro. This makes it possible
-for pcre2test.c to include some of the source files from the libraries using a
-different PRIV definition to avoid name clashes. It also makes it clear in the
-code that a non-static object is being referenced. */
-
-#ifndef PRIV
-#define PRIV(name) _pcre2_##name
-#endif
-
 /* This is an unsigned int value that no UTF character can ever have, as
 Unicode doesn't go beyond 0x0010ffff. */
 
@@ -1985,6 +1960,14 @@ extern int          _pcre2_valid_utf(PCRE2_SPTR, PCRE2_SIZE, PCRE2_SIZE *);
 extern BOOL         _pcre2_was_newline(PCRE2_SPTR, uint32_t, PCRE2_SPTR,
                       uint32_t *, BOOL);
 extern BOOL         _pcre2_xclass(uint32_t, PCRE2_SPTR, BOOL);
+
+/* This function is needed only when memmove() is not available. */
+
+#if !defined(VPCOMPAT) && !defined(HAVE_MEMMOVE)
+#define _pcre2_memmove               PCRE2_SUFFIX(_pcre2_memmove)
+extern void *       _pcre2_memmove(void *, const void *, size_t);
+#endif
+
 #endif  /* PCRE2_CODE_UNIT_WIDTH */
 #endif  /* PCRE2_INTERNAL_H_IDEMPOTENT_GUARD */
 

src/pcre2_string_utils.c

@@ -7,7 +7,7 @@ and semantics are as close as possible to those of the Perl 5 language.
 
                        Written by Philip Hazel
      Original API code Copyright (c) 1997-2012 University of Cambridge
-         New API code Copyright (c) 2016 University of Cambridge
+          New API code Copyright (c) 2018 University of Cambridge
 
 -----------------------------------------------------------------------------
 Redistribution and use in source and binary forms, with or without
@@ -50,6 +50,42 @@ functions work only on 8-bit data. */
 #include "pcre2_internal.h"
 
 
+/*************************************************
+*    Emulated memmove() for systems without it   *
+*************************************************/
+
+/* This function can make use of bcopy() if it is available. Otherwise do it by
+steam, as there some non-Unix environments that lack both memmove() and
+bcopy(). */
+
+#if !defined(VPCOMPAT) && !defined(HAVE_MEMMOVE)
+void *
+PRIV(memmove)(void *d, const void *s, size_t n)
+{
+#ifdef HAVE_BCOPY
+bcopy(s, d, n);
+return d;
+#else
+size_t i;
+unsigned char *dest = (unsigned char *)d;
+const unsigned char *src = (const unsigned char *)s;
+if (dest > src)
+  {
+  dest += n;
+  src += n;
+  for (i = 0; i < n; ++i) *(--dest) = *(--src);
+  return (void *)dest;
+  }
+else
+  {
+  for (i = 0; i < n; ++i) *dest++ = *src++;
+  return (void *)(dest - n);
+  }
+#endif   /* not HAVE_BCOPY */
+}
+#endif   /* not VPCOMPAT && not HAVE_MEMMOVE */
+
+
 /*************************************************
 *    Compare two zero-terminated PCRE2 strings   *
 *************************************************/

src/pcre2grep.c

@@ -469,6 +469,43 @@ const char utf8_table4[] = {
   3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
 
 
+#if !defined(VPCOMPAT) && !defined(HAVE_MEMMOVE)
+/*************************************************
+*    Emulated memmove() for systems without it   *
+*************************************************/
+
+/* This function can make use of bcopy() if it is available. Otherwise do it by
+steam, as there are some non-Unix environments that lack both memmove() and
+bcopy(). */
+
+static void *
+emulated_memmove(void *d, const void *s, size_t n)
+{
+#ifdef HAVE_BCOPY
+bcopy(s, d, n);
+return d;
+#else
+size_t i;
+unsigned char *dest = (unsigned char *)d;
+const unsigned char *src = (const unsigned char *)s;
+if (dest > src)
+  {
+  dest += n;
+  src += n;
+  for (i = 0; i < n; ++i) *(--dest) = *(--src);
+  return (void *)dest;
+  }
+else
+  {
+  for (i = 0; i < n; ++i) *dest++ = *src++;
+  return (void *)(dest - n);
+  }
+#endif   /* not HAVE_BCOPY */
+}
+#undef memmove
+#define memmove(d,s,n) emulated_memmove(d,s,n)
+#endif   /* not VPCOMPAT && not HAVE_MEMMOVE */
+
 
 /*************************************************
 *         Case-independent string compare        *
@@ -2932,7 +2969,7 @@ while (ptr < endptr)
 
     /* Now do the shuffle */
 
-    memmove(main_buffer, main_buffer + bufthird, 2*bufthird);
+    (void)memmove(main_buffer, main_buffer + bufthird, 2*bufthird);
     ptr -= bufthird;
 
     bufflength = 2*bufthird + fill_buffer(handle, frtype,

src/pcre2test.c

@@ -2595,6 +2595,46 @@ static const uint8_t tables2[] = {
 };
 
 
+
+#if !defined(VPCOMPAT) && !defined(HAVE_MEMMOVE)
+/*************************************************
+*    Emulated memmove() for systems without it   *
+*************************************************/
+
+/* This function can make use of bcopy() if it is available. Otherwise do it by
+steam, as there are some non-Unix environments that lack both memmove() and
+bcopy(). */
+
+static void *
+emulated_memmove(void *d, const void *s, size_t n)
+{
+#ifdef HAVE_BCOPY
+bcopy(s, d, n);
+return d;
+#else
+size_t i;
+unsigned char *dest = (unsigned char *)d;
+const unsigned char *src = (const unsigned char *)s;
+if (dest > src)
+  {
+  dest += n;
+  src += n;
+  for (i = 0; i < n; ++i) *(--dest) = *(--src);
+  return (void *)dest;
+  }
+else
+  {
+  for (i = 0; i < n; ++i) *dest++ = *src++;
+  return (void *)(dest - n);
+  }
+#endif   /* not HAVE_BCOPY */
+}
+#undef memmove
+#define memmove(d,s,n) emulated_memmove(d,s,n)
+#endif   /* not VPCOMPAT && not HAVE_MEMMOVE */
+
+
+
 #ifndef HAVE_STRERROR
 /*************************************************
 *     Provide strerror() for non-ANSI libraries  *