xref: /dflybsd-src/contrib/gcc-8.0/libiberty/xmemdup.c (revision 38fd149817dfbff97799f62fcb70be98c4e32523)
1*38fd1498Szrj /* xmemdup.c -- Duplicate a memory buffer, using xmalloc.
2*38fd1498Szrj    This trivial function is in the public domain.
3*38fd1498Szrj    Jeff Garzik, September 1999.  */
4*38fd1498Szrj 
5*38fd1498Szrj /*
6*38fd1498Szrj 
7*38fd1498Szrj @deftypefn Replacement void* xmemdup (void *@var{input}, @
8*38fd1498Szrj   size_t @var{copy_size}, size_t @var{alloc_size})
9*38fd1498Szrj 
10*38fd1498Szrj Duplicates a region of memory without fail.  First, @var{alloc_size} bytes
11*38fd1498Szrj are allocated, then @var{copy_size} bytes from @var{input} are copied into
12*38fd1498Szrj it, and the new memory is returned.  If fewer bytes are copied than were
13*38fd1498Szrj allocated, the remaining memory is zeroed.
14*38fd1498Szrj 
15*38fd1498Szrj @end deftypefn
16*38fd1498Szrj 
17*38fd1498Szrj */
18*38fd1498Szrj 
19*38fd1498Szrj #ifdef HAVE_CONFIG_H
20*38fd1498Szrj #include "config.h"
21*38fd1498Szrj #endif
22*38fd1498Szrj #include "ansidecl.h"
23*38fd1498Szrj #include "libiberty.h"
24*38fd1498Szrj 
25*38fd1498Szrj #include <sys/types.h> /* For size_t. */
26*38fd1498Szrj #ifdef HAVE_STRING_H
27*38fd1498Szrj #include <string.h>
28*38fd1498Szrj #else
29*38fd1498Szrj # ifdef HAVE_STRINGS_H
30*38fd1498Szrj #  include <strings.h>
31*38fd1498Szrj # endif
32*38fd1498Szrj #endif
33*38fd1498Szrj 
34*38fd1498Szrj PTR
xmemdup(const PTR input,size_t copy_size,size_t alloc_size)35*38fd1498Szrj xmemdup (const PTR input, size_t copy_size, size_t alloc_size)
36*38fd1498Szrj {
37*38fd1498Szrj   PTR output = xmalloc (alloc_size);
38*38fd1498Szrj   if (alloc_size > copy_size)
39*38fd1498Szrj     memset ((char *) output + copy_size, 0, alloc_size - copy_size);
40*38fd1498Szrj   return (PTR) memcpy (output, input, copy_size);
41*38fd1498Szrj }
42