stdlib/tst-swapcontext1.c

   1 /* Check multiple makecontext calls.
   2    Copyright (C) 2018-2022 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <ucontext.h>
  22
  23 static ucontext_t uctx_main, uctx_func1, uctx_func2;
  24 const char *str1 = "\e[31mswapcontext(&uctx_func1, &uctx_main)\e[0m";
  25 const char *str2 = "\e[34mswapcontext(&uctx_func2, &uctx_main)\e[0m";
  26 const char *fmt1 = "\e[31m";
  27 const char *fmt2 = "\e[34m";
  28
  29 #define handle_error(msg) \
  30   do { perror(msg); exit(EXIT_FAILURE); } while (0)
  31
  32 __attribute__((noinline, noclone))
  33 static void
  34 func4(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
  35 {
  36   printf("      %sfunc4: %s\e[0m\n", fmt, str);
  37   if (swapcontext(uocp, ucp) == -1)
  38     handle_error("swapcontext");
  39   printf("      %sfunc4: returning\e[0m\n", fmt);
  40 }
  41
  42 __attribute__((noinline, noclone))
  43 static void
  44 func3(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
  45 {
  46   printf("    %sfunc3: func4(uocp, ucp, str)\e[0m\n", fmt);
  47   func4(uocp, ucp, str, fmt);
  48   printf("    %sfunc3: returning\e[0m\n", fmt);
  49 }
  50
  51 __attribute__((noinline, noclone))
  52 static void
  53 func1(void)
  54 {
  55   while ( 1 )
  56     {
  57       printf("  \e[31mfunc1: func3(&uctx_func1, &uctx_main, str1)\e[0m\n");
  58       func3( &uctx_func1, &uctx_main, str1, fmt1);
  59     }
  60 }
  61
  62 __attribute__((noinline, noclone))
  63 static void
  64 func2(void)
  65 {
  66   while ( 1 )
  67     {
  68       printf("  \e[34mfunc2: func3(&uctx_func2, &uctx_main, str2)\e[0m\n");
  69       func3(&uctx_func2, &uctx_main, str2, fmt2);
  70     }
  71 }
  72
  73 static int
  74 do_test (void)
  75 {
  76   char func1_stack[16384];
  77   char func2_stack[16384];
  78   int i;
  79
  80   if (getcontext(&uctx_func1) == -1)
  81     handle_error("getcontext");
  82   uctx_func1.uc_stack.ss_sp = func1_stack;
  83   uctx_func1.uc_stack.ss_size = sizeof (func1_stack);
  84   uctx_func1.uc_link = &uctx_main;
  85   makecontext(&uctx_func1, func1, 0);
  86
  87   if (getcontext(&uctx_func2) == -1)
  88     handle_error("getcontext");
  89   uctx_func2.uc_stack.ss_sp = func2_stack;
  90   uctx_func2.uc_stack.ss_size = sizeof (func2_stack);
  91   uctx_func2.uc_link = &uctx_func1;
  92   makecontext(&uctx_func2, func2, 0);
  93
  94   for ( i = 0; i < 4; i++ )
  95     {
  96       if (swapcontext(&uctx_main, &uctx_func1) == -1)
  97         handle_error("swapcontext");
  98       printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func2)\n\e[0m");
  99       if (swapcontext(&uctx_main, &uctx_func2) == -1)
 100         handle_error("swapcontext");
 101       printf("        \e[35mmain: swapcontext(&uctx_main, &uctx_func1)\n\e[0m");
 102     }
 103
 104   printf("main: exiting\n");
 105   exit(EXIT_SUCCESS);
 106 }
 107
 108 #include <support/test-driver.c>