gprofng/src/dbe_memmgr.c

   1 /* Copyright (C) 2021-2023 Free Software Foundation, Inc.
   2    Contributed by Oracle.
   3
   4    This file is part of GNU Binutils.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3, or (at your option)
   9    any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #include "config.h"
  22 #include <dlfcn.h>
  23 #include "util.h"
  24
  25 #define CHECK_OUT_OF_MEM(ptr, size) if (ptr == NULL) err_out_of_memory(size)
  26
  27 /* Report Out of Memory error and exit */
  28 static void
  29 err_out_of_memory (unsigned nbytes)
  30 {
  31   char *nm = get_prog_name (1);
  32   if (nm)
  33     fprintf (stderr, GTXT ("%s: Error: Memory capacity exceeded.\n"), nm);
  34   else
  35     fprintf (stderr, GTXT ("Error: Memory capacity exceeded.\n"));
  36   fprintf (stderr, GTXT ("  Requested %u bytes.\n"), nbytes);
  37   exit (16);
  38 }
  39
  40 #define CALL_REAL(x) (__real_##x)
  41 #define NULL_PTR(x) ( __real_##x == NULL )
  42
  43 static void *(*__real_malloc)(size_t) = NULL;
  44 static void (*__real_free)(void *) = NULL;
  45 static void *(*__real_realloc)(void *, size_t) = NULL;
  46 static void *(*__real_calloc)(size_t, size_t) = NULL;
  47 static char *(*__real_strdup)(const char*) = NULL;
  48 static volatile int in_init = 0;
  49
  50 static int
  51 init_heap_intf ()
  52 {
  53   in_init = 1;
  54   __real_malloc = (void*(*)(size_t))dlsym (RTLD_NEXT, "malloc");
  55   __real_free = (void(*)(void *))dlsym (RTLD_NEXT, "free");
  56   __real_realloc = (void*(*)(void *, size_t))dlsym (RTLD_NEXT, "realloc");
  57   __real_calloc = (void*(*)(size_t, size_t))dlsym (RTLD_NEXT, "calloc");
  58   __real_strdup = (char*(*)(const char*))dlsym (RTLD_NEXT, "strdup");
  59   in_init = 0;
  60   return 0;
  61 }
  62
  63 /* --------------------------------------------------------------------------- */
  64 /* libc's memory management functions substitutions */
  65
  66 /* Allocate memory and make sure we got some */
  67 void *
  68 malloc (size_t size)
  69 {
  70   if (NULL_PTR (malloc))
  71     init_heap_intf ();
  72   void *ptr = CALL_REAL (malloc)(size);
  73   CHECK_OUT_OF_MEM (ptr, size);
  74   return ptr;
  75 }
  76
  77
  78 /* Implement a workaround for a libdl recursion problem */
  79 void *
  80 calloc (size_t nelem, size_t size)
  81 {
  82   if (NULL_PTR (calloc))
  83     {
  84       /* If a program is linked with libpthread then the following
  85        * calling sequence occurs:
  86        * init_heap_intf -> dlsym -> calloc -> malloc -> init_heap_intf
  87        * We break some performance improvement in libdl by returning
  88        * NULL but preserve functionality.
  89        */
  90       if (in_init)
  91         return NULL;
  92       init_heap_intf ();
  93     }
  94   return CALL_REAL (calloc)(nelem, size);
  95 }
  96
  97 /* Free the storage associated with data */
  98 void
  99 free (void *ptr)
 100 {
 101   if (ptr == NULL)
 102     return;
 103   if (NULL_PTR (free))
 104     init_heap_intf ();
 105   CALL_REAL (free)(ptr);
 106   return;
 107 }
 108
 109 /* Reallocate buffer */
 110 void *
 111 realloc (void *ptr, size_t size)
 112 {
 113   if (NULL_PTR (realloc))
 114     init_heap_intf ();
 115   ptr = CALL_REAL (realloc)(ptr, size);
 116   CHECK_OUT_OF_MEM (ptr, size);
 117   return ptr;
 118 }