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Diffstat (limited to 'mcon/U/d_safemcpy.U')
-rw-r--r-- | mcon/U/d_safemcpy.U | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/mcon/U/d_safemcpy.U b/mcon/U/d_safemcpy.U new file mode 100644 index 0000000..d59475b --- /dev/null +++ b/mcon/U/d_safemcpy.U @@ -0,0 +1,127 @@ +?RCS: $Id$ +?RCS: +?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi +?RCS: +?RCS: You may redistribute only under the terms of the Artistic Licence, +?RCS: as specified in the README file that comes with the distribution. +?RCS: You may reuse parts of this distribution only within the terms of +?RCS: that same Artistic Licence; a copy of which may be found at the root +?RCS: of the source tree for dist 4.0. +?RCS: +?RCS: $Log: d_safemcpy.U,v $ +?RCS: Revision 3.0.1.5 1997/02/28 15:41:12 ram +?RCS: patch61: improved overlapping copy check +?RCS: patch61: comfort them if they have memmove +?RCS: patch61: added ?F: metalint hint +?RCS: +?RCS: Revision 3.0.1.4 1995/07/25 13:58:46 ram +?RCS: patch56: re-arranged compile line to include ldflags before objects +?RCS: +?RCS: Revision 3.0.1.3 1995/03/21 08:47:26 ram +?RCS: patch52: swapped two first arguments of memcpy() calls +?RCS: +?RCS: Revision 3.0.1.2 1994/10/29 16:15:10 ram +?RCS: patch36: added 'ldflags' to the test compile line (ADO) +?RCS: +?RCS: Revision 3.0.1.1 1994/05/06 14:53:12 ram +?RCS: patch23: ensure string is not optimized in read-only memory (ADO) +?RCS: +?RCS: Revision 3.0 1993/08/18 12:06:58 ram +?RCS: Baseline for dist 3.0 netwide release. +?RCS: +?MAKE:d_safemcpy: cat d_memcpy +cc +optimize +ccflags +libs +ldflags rm \ + d_memmove i_memory i_stdlib i_string i_unistd Oldconfig Setvar +?MAKE: -pick add $@ %< +?S:d_safemcpy: +?S: This variable conditionally defines the HAS_SAFE_MEMCPY symbol if +?S: the memcpy() routine can do overlapping copies. +?S:. +?C:HAS_SAFE_MEMCPY (SAFE_MEMCPY): +?C: This symbol, if defined, indicates that the memcpy routine is available +?C: to copy potentially overlapping memory blocks. Otherwise you should +?C: probably use memmove() or memcpy(). If neither is defined, roll your +?C: own version. +?C:. +?H:#$d_safemcpy HAS_SAFE_MEMCPY /**/ +?H:. +?F:!safemcpy +?LINT: set d_safemcpy +: can memcpy handle overlapping blocks? +?X: assume the worst +val="$undef" +case "$d_memcpy" in +"$define") + echo " " + echo "Checking to see if your memcpy() can do overlapping copies..." >&4 + $cat >foo.c <<EOCP +#$i_memory I_MEMORY +#$i_stdlib I_STDLIB +#$i_string I_STRING +#$i_unistd I_UNISTD +EOCP + $cat >>foo.c <<'EOCP' +#include <stdio.h> +#ifdef I_MEMORY +# include <memory.h> +#endif +#ifdef I_STDLIB +# include <stdlib.h> +#endif +#ifdef I_STRING +# include <string.h> +#else +# include <strings.h> +#endif +#ifdef I_UNISTD +# include <unistd.h> /* Needed for NetBSD */ +#endif +int main() +{ +char buf[128], abc[128]; +char *b; +int len; +int off; +int align; + +/* Copy "abcde..." string to char abc[] so that gcc doesn't + try to store the string in read-only memory. */ +memcpy(abc, "abcdefghijklmnopqrstuvwxyz0123456789", 36); + +for (align = 7; align >= 0; align--) { + for (len = 36; len; len--) { + b = buf+align; + memcpy(b, abc, len); + for (off = 1; off <= len; off++) { + memcpy(b+off, b, len); + memcpy(b, b+off, len); + if (memcmp(b, abc, len)) + exit(1); + } + } +} +exit(0); +} +EOCP + if $cc $optimize $ccflags $ldflags \ + -o safemcpy foo.c $libs >/dev/null 2>&1; then + if ./safemcpy 2>/dev/null; then + echo "Yes, it can." + val="$define" + else + echo "It can't, sorry." + case "$d_memmove" in + "$define") echo "But that's Ok since you have memmove()." ;; + esac + fi + else + echo "(I can't compile the test program, so we'll assume not...)" + case "$d_memmove" in + "$define") echo "But that's Ok since you have memmove()." ;; + esac + fi + ;; +esac +$rm -f foo.* safemcpy core +set d_safemcpy +eval $setvar + |