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    1: /* malloc with out of memory checking.
    2:    Copyright (C) 2001-2004, 2006 Free Software Foundation, Inc.
    3:    Written by Bruno Haible <haible@clisp.cons.org>, 2001.
    4: 
    5:    This program is free software: you can redistribute it and/or modify
    6:    it under the terms of the GNU General Public License as published by
    7:    the Free Software Foundation; either version 3 of the License, or
    8:    (at your option) any later version.
    9: 
   10:    This program is distributed in the hope that it will be useful,
   11:    but WITHOUT ANY WARRANTY; without even the implied warranty of
   12:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   13:    GNU General Public License for more details.
   14: 
   15:    You should have received a copy of the GNU General Public License
   16:    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
   17: 
   18: #ifndef _XALLOC_H
   19: #define _XALLOC_H
   20: 
   21: #include <stddef.h>
   22: 
   23: 
   24: #ifdef __cplusplus
   25: extern "C" {
   26: #endif
   27: 
   28: 
   29: /* Defined in xmalloc.c.  */
   30: 
   31: /* Allocate SIZE bytes of memory dynamically, with error checking.  */
   32: extern void *xmalloc (size_t size);
   33: 
   34: /* Allocate memory for NMEMB elements of SIZE bytes, with error checking.
   35:    SIZE must be > 0.  */
   36: extern void *xnmalloc (size_t nmemb, size_t size);
   37: 
   38: /* Allocate SIZE bytes of memory dynamically, with error checking,
   39:    and zero it.  */
   40: extern void *xzalloc (size_t size);
   41: 
   42: /* Allocate memory for NMEMB elements of SIZE bytes, with error checking,
   43:    and zero it.  */
   44: extern void *xcalloc (size_t nmemb, size_t size);
   45: 
   46: /* Change the size of an allocated block of memory PTR to SIZE bytes,
   47:    with error checking.  If PTR is NULL, run xmalloc.  */
   48: extern void *xrealloc (void *ptr, size_t size);
   49: #ifdef __cplusplus
   50: }
   51: template <typename T>
   52:   inline T * xrealloc (T * ptr, size_t size)
   53:   {
   54:     return (T *) xrealloc ((void *) ptr, size);
   55:   }
   56: extern "C" {
   57: #endif
   58: 
   59: /* This function is always triggered when memory is exhausted.  It is
   60:    in charge of honoring the three previous items.  This is the
   61:    function to call when one wants the program to die because of a
   62:    memory allocation failure.  */
   63: extern void xalloc_die (void)
   64: #if (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 5)) && !__STRICT_ANSI__
   65:      __attribute__ ((__noreturn__))
   66: #endif
   67:      ;
   68: 
   69: /* In the following macros, T must be an elementary or structure/union or
   70:    typedef'ed type, or a pointer to such a type.  To apply one of the
   71:    following macros to a function pointer or array type, you need to typedef
   72:    it first and use the typedef name.  */
   73: 
   74: /* Allocate an object of type T dynamically, with error checking.  */
   75: /* extern T *XMALLOC (typename T); */
   76: #define XMALLOC(T) \
   77:   ((T *) xmalloc (sizeof (T)))
   78: 
   79: /* Allocate memory for NMEMB elements of type T, with error checking.  */
   80: /* extern T *XNMALLOC (size_t nmemb, typename T); */
   81: #if HAVE_INLINE
   82: /* xnmalloc performs a division and multiplication by sizeof (T).  Arrange to
   83:    perform the division at compile-time and the multiplication with a factor
   84:    known at compile-time.  */
   85: # define XNMALLOC(N,T) \
   86:    ((T *) (sizeof (T) == 1 \
   87: 	   ? xmalloc (N) \
   88: 	   : xnboundedmalloc(N, (size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / sizeof (T), sizeof (T))))
   89: static inline void *
   90: xnboundedmalloc (size_t n, size_t bound, size_t s)
   91: {
   92:   if (n > bound)
   93:     xalloc_die ();
   94:   return xmalloc (n * s);
   95: }
   96: #else
   97: # define XNMALLOC(N,T) \
   98:    ((T *) (sizeof (T) == 1 ? xmalloc (N) : xnmalloc (N, sizeof (T))))
   99: #endif
  100: 
  101: /* Allocate an object of type T dynamically, with error checking,
  102:    and zero it.  */
  103: /* extern T *XZALLOC (typename T); */
  104: #define XZALLOC(T) \
  105:   ((T *) xzalloc (sizeof (T)))
  106: 
  107: /* Allocate memory for NMEMB elements of type T, with error checking,
  108:    and zero it.  */
  109: /* extern T *XCALLOC (size_t nmemb, typename T); */
  110: #define XCALLOC(N,T) \
  111:   ((T *) xcalloc (N, sizeof (T)))
  112: 
  113: /* Return a pointer to a new buffer of N bytes.  This is like xmalloc,
  114:    except it returns char *.  */
  115: #define xcharalloc(N) \
  116:   XNMALLOC (N, char)
  117: 
  118: 
  119: /* Defined in xstrdup.c.  */
  120: 
  121: /* Return a newly allocated copy of the N bytes of memory starting at P.  */
  122: extern void *xmemdup (const void *p, size_t n);
  123: #ifdef __cplusplus
  124: }
  125: template <typename T>
  126:   inline T * xmemdup (const T * p, size_t n)
  127:   {
  128:     return (T *) xmemdup ((const void *) p, n);
  129:   }
  130: extern "C" {
  131: #endif
  132: 
  133: /* Return a newly allocated copy of STRING.  */
  134: extern char *xstrdup (const char *string);
  135: 
  136: 
  137: /* Return 1 if an array of N objects, each of size S, cannot exist due
  138:    to size arithmetic overflow.  S must be positive and N must be
  139:    nonnegative.  This is a macro, not an inline function, so that it
  140:    works correctly even when SIZE_MAX < N.
  141: 
  142:    By gnulib convention, SIZE_MAX represents overflow in size
  143:    calculations, so the conservative dividend to use here is
  144:    SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
  145:    However, malloc (SIZE_MAX) fails on all known hosts where
  146:    sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
  147:    exactly-SIZE_MAX allocations on such hosts; this avoids a test and
  148:    branch when S is known to be 1.  */
  149: # define xalloc_oversized(n, s) \
  150:     ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
  151: 
  152: 
  153: #ifdef __cplusplus
  154: }
  155: #endif
  156: 
  157: 
  158: #endif /* _XALLOC_H */