tests/lib/libc/sys/t_swapcontext.c

   1 /* $NetBSD: t_swapcontext.c,v 1.3 2013/05/05 10:28:11 skrll Exp $ */
   2
   3 /*
   4  * Copyright (c) 2012 Emmanuel Dreyfus. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  19  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  20  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  24  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  25  * POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __RCSID("$NetBSD");
  30
  31 #include <ucontext.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <lwp.h>
  35
  36 #include <atf-c.h>
  37
  38 #define STACKSIZE 65536
  39
  40 char stack[STACKSIZE];
  41 ucontext_t nctx;
  42 ucontext_t octx;
  43 void *otls;
  44 void *ntls;
  45 int val1, val2;
  46 int alter_tlsbase;
  47
  48 /* ARGSUSED0 */
  49 static void
  50 swapfunc(void *arg)
  51 {
  52         ntls = _lwp_getprivate();
  53         printf("after swapcontext TLS pointer = %p\n", ntls);
  54
  55         if (alter_tlsbase) {
  56                 ATF_REQUIRE_EQ(ntls, &val1);
  57                 printf("TLS pointer modified by swapcontext()\n");
  58         } else {
  59                 ATF_REQUIRE_EQ(ntls, &val2);
  60                 printf("TLS pointer left untouched by swapcontext()\n");
  61         }
  62
  63         /* Go back in main */
  64         ATF_REQUIRE(swapcontext(&nctx, &octx));
  65
  66         /* NOTREACHED */
  67         return;
  68 }
  69
  70 static void
  71 mainfunc(void)
  72 {
  73         printf("Testing if swapcontext() alters TLS pointer if _UC_TLSBASE "
  74                "is %s\n", (alter_tlsbase) ? "left set" : "cleared");
  75
  76         _lwp_setprivate(&val1);
  77         printf("before swapcontext TLS pointer = %p\n", &val1);
  78
  79         ATF_REQUIRE(getcontext(&nctx) == 0);
  80
  81         nctx.uc_stack.ss_sp = stack;
  82         nctx.uc_stack.ss_size = sizeof(stack);
  83
  84 #ifndef _UC_TLSBASE
  85         ATF_REQUIRE_MSG(0, "_UC_TLSBASE is not defined");
  86 #else /* _UC_TLSBASE */
  87         ATF_REQUIRE(nctx.uc_flags & _UC_TLSBASE);
  88         if (!alter_tlsbase)
  89                 nctx.uc_flags &= ~_UC_TLSBASE;
  90 #endif /* _UC_TLSBASE */
  91
  92         makecontext(&nctx, swapfunc, 0);
  93
  94         _lwp_setprivate(&val2);
  95         otls = _lwp_getprivate();
  96         printf("before swapcontext TLS pointer = %p\n", otls);
  97         ATF_REQUIRE(swapcontext(&octx, &nctx) == 0);
  98
  99         printf("Test completed\n");
 100 }
 101
 102
 103 ATF_TC(swapcontext1);
 104 ATF_TC_HEAD(swapcontext1, tc)
 105 {
 106         atf_tc_set_md_var(tc, "descr", "Testing if swapcontext() can let "
 107             "TLS pointer untouched");
 108 }
 109 ATF_TC_BODY(swapcontext1, tc)
 110 {
 111         alter_tlsbase = 0;
 112         mainfunc();
 113 }
 114
 115 ATF_TC(swapcontext2);
 116 ATF_TC_HEAD(swapcontext2, tc)
 117 {
 118         atf_tc_set_md_var(tc, "descr", "Testing if swapcontext() can "
 119             "modify TLS pointer");
 120 }
 121 ATF_TC_BODY(swapcontext2, tc)
 122 {
 123         alter_tlsbase = 1;
 124         mainfunc();
 125 }
 126
 127 ATF_TP_ADD_TCS(tp)
 128 {
 129         ATF_TP_ADD_TC(tp, swapcontext1);
 130         ATF_TP_ADD_TC(tp, swapcontext2);
 131
 132         return atf_no_error();
 133 }