X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fxalloc.h;h=5f891457ba7476f5094cff1516d8093ff3a227d4;hb=cd56634a4a8179fd5a4419fbb3e27211b042ab1c;hp=f75c3cdd7848d913af95966392ccce355f1f8435;hpb=9d67945fdbdd4afc1ef1be5d68ace53aba73fa34;p=gnulib.git diff --git a/lib/xalloc.h b/lib/xalloc.h index f75c3cdd7..5f891457b 100644 --- a/lib/xalloc.h +++ b/lib/xalloc.h @@ -1,10 +1,11 @@ /* xalloc.h -- malloc with out-of-memory checking - Copyright (C) 1990-1998, 1999 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or modify + Copyright (C) 1990-2000, 2003-2004, 2006-2014 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2, or (at your option) - any later version. + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -12,74 +13,251 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software Foundation, - Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + along with this program. If not, see . */ #ifndef XALLOC_H_ -# define XALLOC_H_ - -# ifndef PARAMS -# if defined PROTOTYPES || (defined __STDC__ && __STDC__) -# define PARAMS(Args) Args -# else -# define PARAMS(Args) () -# endif -# endif - -# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7) -# define __attribute__(x) -# endif - -# ifndef ATTRIBUTE_NORETURN -# define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__)) -# endif - -/* Exit value when the requested amount of memory is not available. - It is initialized to EXIT_FAILURE, but the caller may set it to - some other value. */ -extern int xalloc_exit_failure; - -/* If this pointer is non-zero, run the specified function upon each - allocation failure. It is initialized to zero. */ -extern void (*xalloc_fail_func) PARAMS ((void)); - -/* If XALLOC_FAIL_FUNC is undefined or a function that returns, this - message must be non-NULL. It is translated via gettext. - The default value is "Memory exhausted". */ -extern char *const xalloc_msg_memory_exhausted; - -/* This function is always triggered when memory is exhausted. It is - in charge of honoring the three previous items. This is the +#define XALLOC_H_ + +#include + +#include "xalloc-oversized.h" + +#ifndef _GL_INLINE_HEADER_BEGIN + #error "Please include config.h first." +#endif +_GL_INLINE_HEADER_BEGIN +#ifndef XALLOC_INLINE +# define XALLOC_INLINE _GL_INLINE +#endif + +#ifdef __cplusplus +extern "C" { +#endif + + +#if __GNUC__ >= 3 +# define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) +#else +# define _GL_ATTRIBUTE_MALLOC +#endif + +#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3) +# define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args)) +#else +# define _GL_ATTRIBUTE_ALLOC_SIZE(args) +#endif + +/* This function is always triggered when memory is exhausted. + It must be defined by the application, either explicitly + or by using gnulib's xalloc-die module. This is the function to call when one wants the program to die because of a memory allocation failure. */ -extern void xalloc_die PARAMS ((void)) ATTRIBUTE_NORETURN; - -void *xmalloc PARAMS ((size_t n)); -void *xcalloc PARAMS ((size_t n, size_t s)); -void *xrealloc PARAMS ((void *p, size_t n)); -char *xstrdup PARAMS ((const char *str)); - -# define XMALLOC(Type, N_bytes) ((Type *) xmalloc (sizeof (Type) * (N_bytes))) -# define XCALLOC(Type, N_bytes) ((Type *) xcalloc (sizeof (Type), (N_bytes))) -# define XREALLOC(Ptr, Type, N_bytes) \ - ((Type *) xrealloc ((void *) (Ptr), sizeof (Type) * (N_bytes))) - -/* Declare and alloc memory for VAR of type TYPE. */ -# define NEW(Type, Var) Type *(Var) = XMALLOC (Type, 1) - -/* Free VAR only if non NULL. */ -# define XFREE(Var) \ - do { \ - if (Var) \ - free (Var); \ - } while (0) - -/* Return a pointer to a malloc'ed copy of the array SRC of NUM elements. */ -# define CCLONE(Src, Num) \ - (memcpy (xmalloc (sizeof (*Src) * (Num)), (Src), sizeof (*Src) * (Num))) - -/* Return a malloc'ed copy of SRC. */ -# define CLONE(Src) CCLONE (Src, 1) +extern _Noreturn void xalloc_die (void); + +void *xmalloc (size_t s) + _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_ALLOC_SIZE ((1)); +void *xzalloc (size_t s) + _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_ALLOC_SIZE ((1)); +void *xcalloc (size_t n, size_t s) + _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_ALLOC_SIZE ((1, 2)); +void *xrealloc (void *p, size_t s) + _GL_ATTRIBUTE_ALLOC_SIZE ((2)); +void *x2realloc (void *p, size_t *pn); +void *xmemdup (void const *p, size_t s) + _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_ALLOC_SIZE ((2)); +char *xstrdup (char const *str) + _GL_ATTRIBUTE_MALLOC; + +/* In the following macros, T must be an elementary or structure/union or + typedef'ed type, or a pointer to such a type. To apply one of the + following macros to a function pointer or array type, you need to typedef + it first and use the typedef name. */ + +/* Allocate an object of type T dynamically, with error checking. */ +/* extern t *XMALLOC (typename t); */ +#define XMALLOC(t) ((t *) xmalloc (sizeof (t))) + +/* Allocate memory for N elements of type T, with error checking. */ +/* extern t *XNMALLOC (size_t n, typename t); */ +#define XNMALLOC(n, t) \ + ((t *) (sizeof (t) == 1 ? xmalloc (n) : xnmalloc (n, sizeof (t)))) + +/* Allocate an object of type T dynamically, with error checking, + and zero it. */ +/* extern t *XZALLOC (typename t); */ +#define XZALLOC(t) ((t *) xzalloc (sizeof (t))) + +/* Allocate memory for N elements of type T, with error checking, + and zero it. */ +/* extern t *XCALLOC (size_t n, typename t); */ +#define XCALLOC(n, t) \ + ((t *) (sizeof (t) == 1 ? xzalloc (n) : xcalloc (n, sizeof (t)))) + + +/* Allocate an array of N objects, each with S bytes of memory, + dynamically, with error checking. S must be nonzero. */ + +XALLOC_INLINE void *xnmalloc (size_t n, size_t s) + _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_ALLOC_SIZE ((1, 2)); +XALLOC_INLINE void * +xnmalloc (size_t n, size_t s) +{ + if (xalloc_oversized (n, s)) + xalloc_die (); + return xmalloc (n * s); +} + +/* Change the size of an allocated block of memory P to an array of N + objects each of S bytes, with error checking. S must be nonzero. */ + +XALLOC_INLINE void *xnrealloc (void *p, size_t n, size_t s) + _GL_ATTRIBUTE_ALLOC_SIZE ((2, 3)); +XALLOC_INLINE void * +xnrealloc (void *p, size_t n, size_t s) +{ + if (xalloc_oversized (n, s)) + xalloc_die (); + return xrealloc (p, n * s); +} + +/* If P is null, allocate a block of at least *PN such objects; + otherwise, reallocate P so that it contains more than *PN objects + each of S bytes. *PN must be nonzero unless P is null, and S must + be nonzero. Set *PN to the new number of objects, and return the + pointer to the new block. *PN is never set to zero, and the + returned pointer is never null. + + Repeated reallocations are guaranteed to make progress, either by + allocating an initial block with a nonzero size, or by allocating a + larger block. + + In the following implementation, nonzero sizes are increased by a + factor of approximately 1.5 so that repeated reallocations have + O(N) overall cost rather than O(N**2) cost, but the + specification for this function does not guarantee that rate. + + Here is an example of use: + + int *p = NULL; + size_t used = 0; + size_t allocated = 0; + + void + append_int (int value) + { + if (used == allocated) + p = x2nrealloc (p, &allocated, sizeof *p); + p[used++] = value; + } + + This causes x2nrealloc to allocate a block of some nonzero size the + first time it is called. + + To have finer-grained control over the initial size, set *PN to a + nonzero value before calling this function with P == NULL. For + example: + + int *p = NULL; + size_t used = 0; + size_t allocated = 0; + size_t allocated1 = 1000; + + void + append_int (int value) + { + if (used == allocated) + { + p = x2nrealloc (p, &allocated1, sizeof *p); + allocated = allocated1; + } + p[used++] = value; + } + + */ + +XALLOC_INLINE void * +x2nrealloc (void *p, size_t *pn, size_t s) +{ + size_t n = *pn; + + if (! p) + { + if (! n) + { + /* The approximate size to use for initial small allocation + requests, when the invoking code specifies an old size of + zero. This is the largest "small" request for the GNU C + library malloc. */ + enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 }; + + n = DEFAULT_MXFAST / s; + n += !n; + } + } + else + { + /* Set N = ceil (1.5 * N) so that progress is made if N == 1. + Check for overflow, so that N * S stays in size_t range. + The check is slightly conservative, but an exact check isn't + worth the trouble. */ + if ((size_t) -1 / 3 * 2 / s <= n) + xalloc_die (); + n += (n + 1) / 2; + } + + *pn = n; + return xrealloc (p, n * s); +} + +/* Return a pointer to a new buffer of N bytes. This is like xmalloc, + except it returns char *. */ + +XALLOC_INLINE char *xcharalloc (size_t n) + _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_ALLOC_SIZE ((1)); +XALLOC_INLINE char * +xcharalloc (size_t n) +{ + return XNMALLOC (n, char); +} + +#ifdef __cplusplus +} + +/* C++ does not allow conversions from void * to other pointer types + without a cast. Use templates to work around the problem when + possible. */ + +template inline T * +xrealloc (T *p, size_t s) +{ + return (T *) xrealloc ((void *) p, s); +} + +template inline T * +xnrealloc (T *p, size_t n, size_t s) +{ + return (T *) xnrealloc ((void *) p, n, s); +} + +template inline T * +x2realloc (T *p, size_t *pn) +{ + return (T *) x2realloc ((void *) p, pn); +} + +template inline T * +x2nrealloc (T *p, size_t *pn, size_t s) +{ + return (T *) x2nrealloc ((void *) p, pn, s); +} + +template inline T * +xmemdup (T const *p, size_t s) +{ + return (T *) xmemdup ((void const *) p, s); +} + +#endif #endif /* !XALLOC_H_ */