nptl/tst-context1.c

   1 /* Copyright (C) 2003-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <error.h>
  21 #include <limits.h>
  22 #include <pthread.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <ucontext.h>
  26
  27 #define N       4
  28 #if __WORDSIZE == 64
  29 #define GUARD_PATTERN 0xdeadbeafdeadbeaf
  30 #else
  31 #define GUARD_PATTERN 0xdeadbeaf
  32 #endif
  33
  34 typedef struct {
  35        ucontext_t uctx;
  36        unsigned long    guard[3];
  37    } tst_context_t;
  38
  39 static char stacks[N][2 * PTHREAD_STACK_MIN];
  40 static tst_context_t ctx[N][2];
  41 static volatile int failures;
  42
  43
  44 static void
  45 fct (long int n)
  46 {
  47   char on_stack[1];
  48
  49   /* Just to use the thread local descriptor.  */
  50   printf ("%ld: in %s now, on_stack = %p\n", n, __FUNCTION__, on_stack);
  51   errno = 0;
  52
  53   if (ctx[n][1].uctx.uc_link != &ctx[n][0].uctx)
  54     {
  55       printf ("context[%ld][1] uc_link damaged, = %p\n", n,
  56               ctx[n][1].uctx.uc_link);
  57       exit (1);
  58     }
  59
  60   if ((ctx[n][0].guard[0] != GUARD_PATTERN)
  61   ||  (ctx[n][0].guard[1] != GUARD_PATTERN)
  62   ||  (ctx[n][0].guard[2] != GUARD_PATTERN))
  63     {
  64       printf ("%ld: %s context[0] overflow detected!\n", n, __FUNCTION__);
  65       ++failures;
  66     }
  67
  68   if ((ctx[n][1].guard[0] != GUARD_PATTERN)
  69   ||  (ctx[n][1].guard[1] != GUARD_PATTERN)
  70   ||  (ctx[n][1].guard[2] != GUARD_PATTERN))
  71     {
  72       printf ("%ld: %s context[1] overflow detected!\n", n, __FUNCTION__);
  73       ++failures;
  74     }
  75
  76   if (n < 0 || n >= N)
  77     {
  78       printf ("%ld out of range\n", n);
  79       exit (1);
  80     }
  81
  82   if (on_stack < stacks[n] || on_stack >= stacks[n] + sizeof (stacks[0]))
  83     {
  84       printf ("%ld: on_stack not on appropriate stack\n", n);
  85       exit (1);
  86     }
  87 }
  88
  89
  90 static void *
  91 tf (void *arg)
  92 {
  93   int n = (int) (long int) arg;
  94
  95   ctx[n][0].guard[0] = GUARD_PATTERN;
  96   ctx[n][0].guard[1] = GUARD_PATTERN;
  97   ctx[n][0].guard[2] = GUARD_PATTERN;
  98
  99   ctx[n][1].guard[0] = GUARD_PATTERN;
 100   ctx[n][1].guard[1] = GUARD_PATTERN;
 101   ctx[n][1].guard[2] = GUARD_PATTERN;
 102
 103   if (getcontext (&ctx[n][1].uctx) != 0)
 104     {
 105       printf ("%d: cannot get context: %m\n", n);
 106       exit (1);
 107     }
 108
 109   printf ("%d: %s: before makecontext\n", n, __FUNCTION__);
 110
 111   ctx[n][1].uctx.uc_stack.ss_sp = stacks[n];
 112   ctx[n][1].uctx.uc_stack.ss_size = sizeof (stacks[n]);
 113   ctx[n][1].uctx.uc_link = &ctx[n][0].uctx;
 114   makecontext (&ctx[n][1].uctx, (void (*) (void)) fct, 1, (long int) n);
 115
 116   printf ("%d: %s: before swapcontext\n", n, __FUNCTION__);
 117
 118   if (swapcontext (&ctx[n][0].uctx, &ctx[n][1].uctx) != 0)
 119     {
 120       ++failures;
 121       printf ("%d: %s: swapcontext failed\n", n, __FUNCTION__);
 122     }
 123   else
 124     printf ("%d: back in %s\n", n, __FUNCTION__);
 125
 126   return NULL;
 127 }
 128
 129
 130 static volatile int global;
 131
 132
 133 static int
 134 do_test (void)
 135 {
 136   int n;
 137   pthread_t th[N];
 138   ucontext_t mctx;
 139
 140   puts ("making contexts");
 141   if (getcontext (&mctx) != 0)
 142     {
 143       if (errno == ENOSYS)
 144         {
 145           puts ("context handling not supported");
 146           exit (0);
 147         }
 148
 149       printf ("%s: getcontext: %m\n", __FUNCTION__);
 150       exit (1);
 151     }
 152
 153   /* Play some tricks with this context.  */
 154   if (++global == 1)
 155     if (setcontext (&mctx) != 0)
 156       {
 157         puts ("setcontext failed");
 158         exit (1);
 159       }
 160   if (global != 2)
 161     {
 162       puts ("global not incremented twice");
 163       exit (1);
 164     }
 165   puts ("global OK");
 166
 167   pthread_attr_t at;
 168
 169   if (pthread_attr_init (&at) != 0)
 170     {
 171       puts ("attr_init failed");
 172       return 1;
 173     }
 174
 175   if (pthread_attr_setstacksize (&at, 1 * 1024 * 1024) != 0)
 176     {
 177       puts ("attr_setstacksize failed");
 178       return 1;
 179     }
 180
 181   for (n = 0; n < N; ++n)
 182     if (pthread_create (&th[n], &at, tf, (void *) (long int) n) != 0)
 183       {
 184         puts ("create failed");
 185         exit (1);
 186       }
 187
 188   if (pthread_attr_destroy (&at) != 0)
 189     {
 190       puts ("attr_destroy failed");
 191       return 1;
 192     }
 193
 194   for (n = 0; n < N; ++n)
 195     if (pthread_join (th[n], NULL) != 0)
 196       {
 197         puts ("join failed");
 198         exit (1);
 199       }
 200
 201   return failures;
 202 }
 203
 204 #define TEST_FUNCTION do_test ()
 205 #include "../test-skeleton.c"