mdw@git.distorted.org.uk Git - mLib/blob - mem/alloc.c

   1 /* -*-c-*-
   2  *
   3  * Memory allocation functions
   4  *
   5  * (c) 1998 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the mLib utilities library.
  11  *
  12  * mLib is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * mLib is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with mLib; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 /*----- Header files ------------------------------------------------------*/
  29
  30 /* --- ANSI headers --- */
  31
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35
  36 /* --- Local headers --- */
  37
  38 #include "alloc.h"
  39 #include "arena.h"
  40 #include "exc.h"
  41
  42 /*----- Functions and macros ----------------------------------------------*/
  43
  44 /* --- @x_alloc@, @x_allocn@ --- *
  45  *
  46  * Arguments:   @arena *a@ = pointer to underlying arena
  47  *              @size_t n@ = number of elements to allocate (for @x_allocv@)
  48  *              @size_t sz@ = size of elements to allocate
  49  *
  50  * Returns:     Pointer to allocated block.
  51  *
  52  * Use:         The @x_allocn@ function allocates memory for @n@ elements of
  53  *              @sz@ bytes each (or, perhaps, %%\emph{vice versa}).  The
  54  *              @x_alloc@ function is the same, but with @n@ fixed equal
  55  *              to 1.  If there's not enough memory, the exception
  56  *              @EXC_NOMEM@ is thrown.
  57  */
  58
  59 void *x_alloc(arena *a, size_t sz)
  60 {
  61   void *p;
  62
  63   p = A_ALLOC(a, sz);
  64     if (!p) THROW(EXC_NOMEM);
  65     else return (p);
  66 }
  67
  68 void *x_allocv(arena *a, size_t n, size_t sz)
  69 {
  70   void *p;
  71
  72   p = A_ALLOCV(a, n, sz);
  73     if (!p) THROW(EXC_NOMEM);
  74     else return (p);
  75 }
  76
  77 /* --- @x_strdup@ --- *
  78  *
  79  * Arguments:   @arena *a@ = pointer to underlying arena
  80  *              @const char *s@ = pointer to a string
  81  *
  82  * Returns:     Pointer to a copy of the string.
  83  *
  84  * Use:         Copies a string (like @strdup@ would, if it existed).  If
  85  *              there's not enough memory, the exception @EXC_NOMEM@ is
  86  *              thrown.
  87  */
  88
  89 char *x_strdup(arena *a, const char *s)
  90 {
  91   char *p; size_t sz;
  92
  93   sz = strlen(s) + 1; p = x_alloc(a, sz); memcpy(p, s, sz);
  94   return (p);
  95 }
  96
  97 /* --- @x_realloc@, @x_reallocv@ --- *
  98  *
  99  * Arguments:   @arena *a@ = pointer to underlying arena
 100  *              @void *p@ = pointer to a block of memory
 101  *              @size_t n@ = new number of elements (for @x_reallocv@)
 102  *              @size_t on@ = old  number of elements (for @x_reallocv@)
 103  *              @size_t sz@ = size of elements (for @x_reallocv@) or new
 104  *                      block size (for @x_realloc@)
 105  *              @size_t osz@ = size of the old block (for @x_realloc@)
 106  *
 107  * Returns:     Pointer to the resized memory block (which is almost
 108  *              certainly not in the same place any more).
 109  *
 110  * Use:         Resizes a memory block.  If there's not enough memory, the
 111  *              exception @EXC_NOMEM@ is thrown.
 112  *
 113  *              The @x_reallocv@ function adjusts a block which currently has
 114  *              space for @on@ elements each of size @sz@, so that it now has
 115  *              enough space for @n@ elements, preserving the initial @min(n,
 116  *              on)@ elements.  The @x_realloc@ function is the same, but
 117  *              with @sz@ fixed equal to 1, and @n@ and @on@ renamed to @sz@
 118  *              and @osz@ for historical reasons.
 119  */
 120
 121 void *x_realloc(arena *a, void *p, size_t sz, size_t osz)
 122 {
 123   p = A_REALLOC(a, p, sz, osz);
 124     if (!p) THROW(EXC_NOMEM);
 125     else return (p);
 126 }
 127
 128 void *x_reallocv(arena *a, void *p, size_t n, size_t on, size_t sz)
 129 {
 130   p = A_REALLOCV(a, p, n, on, sz);
 131     if (!p) THROW(EXC_NOMEM);
 132     else return (p);
 133 }
 134
 135 /* --- @x_free@ --- *
 136  *
 137  * Arguments:   @arena *a@ = pointer to underlying arena
 138  *              @void *p@ = pointer to a block of memory.
 139  *
 140  * Returns:     ---
 141  *
 142  * Use:         Frees a block of memory.
 143  */
 144
 145 void (x_free)(arena *a, void *p) { x_free(a, p); }
 146
 147 /*----- Old functions for the standard arena ------------------------------*/
 148
 149 /* --- @xmalloc@, @xmallocv@ --- *
 150  *
 151  * Arguments:   @size_t n@ = number of elements to allocate (for @xmallocv@)
 152  *              @size_t sz@ = size of block to allocate
 153  *
 154  * Returns:     Pointer to allocated block.
 155  *
 156  * Use:         Allocates memory for @n@ elements each of size @sz@.  For
 157  *              @xmalloc@, @n@ is fixed equal to 1.  If there's not enough
 158  *              memory, the exception @EXC_NOMEM@ is thrown.
 159  */
 160
 161 void *(xmalloc)(size_t sz) { return xmalloc(sz); }
 162 void *(xmallocv)(size_t n, size_t sz) { return xmallocv(n, sz); }
 163
 164 /* --- @xstrdup@ --- *
 165  *
 166  * Arguments:   @const char *s@ = pointer to a string
 167  *
 168  * Returns:     Pointer to a copy of the string.
 169  *
 170  * Use:         Copies a string (like @strdup@ would, if it existed).  If
 171  *              there's not enough memory, the exception @EXC_NOMEM@ is
 172  *              thrown.
 173  */
 174
 175 char *(xstrdup)(const char *s) { return xstrdup(s); }
 176
 177 /* --- @xrealloc@, @xreallocv@ --- *
 178  *
 179  * Arguments:   @void *p@ = pointer to a block of memory
 180  *              @size_t n@ = new number of elements (for @xreallocv@)
 181  *              @size_t on@ = old  number of elements (for @xreallocv@)
 182  *              @size_t sz@ = size of elements (for @xreallocv@) or new
 183  *                      block size (for @xrealloc@)
 184  *              @size_t osz@ = size of the old block (for @xrealloc@)
 185  *
 186  * Returns:     Pointer to the resized memory block (which is almost
 187  *              certainly not in the same place any more).
 188  *
 189  * Use:         Resizes a memory block.  If there's not enough memory, the
 190  *              exception @EXC_NOMEM@ is thrown.
 191  *
 192  *              The @xreallocv@ function adjusts a block which currently has
 193  *              space for @on@ elements each of size @sz@, so that it now has
 194  *              enough space for @n@ elements, preserving the initial @min(n,
 195  *              on)@ elements.  The @xrealloc@ function is the same, but
 196  *              with @sz@ fixed equal to 1, and @n@ and @on@ renamed to @sz@
 197  *              and @osz@ for historical reasons.
 198  */
 199
 200 void *(xrealloc)(void *p, size_t sz, size_t osz)
 201   { return xrealloc(p, sz, osz); }
 202 void *(xreallocv)(void *p, size_t n, size_t on, size_t sz)
 203   { return xreallocv(p, n, on, sz); }
 204
 205 /* --- @xfree@ --- *
 206  *
 207  * Arguments:   @void *p@ = pointer to a block of memory.
 208  *
 209  * Returns:     ---
 210  *
 211  * Use:         Frees a block of memory.
 212  */
 213
 214 void (xfree)(void *p) { xfree(p); }
 215
 216 /*----- That's all, folks -------------------------------------------------*/