mdw@git.distorted.org.uk Git - sod/blob - lib/sod-hosted.c

   1 /* -*-c-*-
   2  *
   3  * Runtime support for SOD requiring hosted implementation
   4  *
   5  * (c) 2015 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the Sensible Object Design, an object system for C.
  11  *
  12  * SOD 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  * SOD 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 SOD; 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 #include <stdio.h>
  31 #include <stdlib.h>
  32
  33 #include "sod.h"
  34
  35 /*----- Preliminary macros ------------------------------------------------*/
  36
  37 #if __STDC_VERSION__ >= 199901
  38 #  define PRIuSZ "zu"
  39 #  define PRINT_SZ(x) (x)
  40 #else
  41 #  define PRIuSZ "lu"
  42 #  define PRINT_SZ(x) ((unsigned long)(x))
  43 #endif
  44
  45 /*----- Main code ---------------------------------------------------------*/
  46
  47 /* --- @sod__chksz_fail@ --- *
  48  *
  49  * Arguments:   @const SodClass *cls@ = class we were trying to instantiate
  50  *              @size_t sz@ = size allocated
  51  *
  52  * Returns:     Doesn't.
  53  *
  54  * Use:         Reports instantiation failure caused by a mismatch between
  55  *              the size allocated (@sz@) and the size required for an
  56  *              instance of class @cls@.
  57  */
  58
  59 SOD__NORETURN void sod__chksz_fail(const SodClass *cls, size_t sz)
  60 {
  61   fprintf(stderr, "INTERNAL ERROR: size mismatch for class `%s': "
  62           "%"PRIuSZ" allocated but %"PRIuSZ" required",
  63           cls->cls.name, PRINT_SZ(sz), PRINT_SZ(cls->cls.initsz));
  64   abort();
  65 }
  66
  67 /* --- @sod_make@, @sod_makev@ --- *
  68  *
  69  * Arguments:   @const SodClass *cls@ = class object for new instance
  70  *              @va_list ap, ...@ = initialization keyword arguments
  71  *
  72  * Returns:     Pointer to the newly-allocated initialized instance, or null.
  73  *
  74  * Use:         Allocates storage for a new instance, initializes it, and
  75  *              returns a pointer to it.  If allocation fails, a null pointer
  76  *              is returned instead.
  77  *
  78  *              This function will allocate the storage using @malloc@, and
  79  *              then initialize it as for @sod_init@.
  80  *
  81  *              It's usually convenient to use the macro @SOD_MAKE@ rather
  82  *              than calling @sod_make@ directly.
  83  *
  84  *              (This function is not available in freestanding environments
  85  *              lacking @malloc@ and @free@.)
  86  */
  87
  88 void *sod_make(const SodClass *cls, ...)
  89 {
  90   void *p;
  91   va_list ap;
  92
  93   va_start(ap, cls);
  94   p = sod_makev(cls, ap);
  95   va_end(ap);
  96   return (p);
  97 }
  98
  99 void *sod_makev(const SodClass *cls, va_list ap)
 100 {
 101   void *p;
 102
 103   p = malloc(cls->cls.initsz); if (!p) return (0);
 104   return (sod_initv(cls, p, ap));
 105 }
 106
 107 /* --- @sod_destroy@ --- *
 108  *
 109  * Arguments:   @void *p@ = pointer to an instance to be torn down, or null
 110  *
 111  * Returns:     Zero if the object was freed; nonzero if it refused for some
 112  *              reason.
 113  *
 114  * Use:         Invokes the instance's `teardown' method to release any held
 115  *              resources, and then calls @free@ to release the instance's
 116  *              storage.  See @sod_teardown@ for details, especially
 117  *              regarding the return value's meaning.
 118  *
 119  *              If @p@ is null, then this function does nothing except
 120  *              returns zero.
 121  *
 122  *              (This function is not available in freestanding environments
 123  *              lacking @malloc@ and @free@.)
 124  */
 125
 126 int sod_destroy(void *p)
 127 {
 128   int rc;
 129
 130   if (!p) return (0);
 131   rc = sod_teardown(p);
 132   if (!rc) free(p);
 133   return (rc);
 134 }
 135
 136 /*----- That's all, folks -------------------------------------------------*/