gdb/testsuite/gdb.base/catch-syscall.c

   1 /* This file is used to test the 'catch syscall' feature on GDB.
   2
   3    Please, if you are going to edit this file DO NOT change the syscalls
   4    being called (nor the order of them).  If you really must do this, then
   5    take a look at catch-syscall.exp and modify there too.
   6
   7    Written by Sergio Durigan Junior <sergiodj@linux.vnet.ibm.com>
   8    September, 2008 */
   9
  10 #include <unistd.h>
  11 #include <sys/syscall.h>
  12 #include <fcntl.h>
  13 #include <sys/stat.h>
  14 #include <sched.h>
  15
  16 /* These are the syscalls numbers used by the test.  */
  17
  18 int close_syscall = SYS_close;
  19 int chroot_syscall = SYS_chroot;
  20 /* GDB had a bug where it couldn't catch syscall number 0 (PR 16297).
  21    In most GNU/Linux architectures, syscall number 0 is
  22    restart_syscall, which can't be called from userspace.  However,
  23    the "read" syscall is zero on x86_64.  */
  24 int read_syscall = SYS_read;
  25 #ifdef SYS_pipe
  26 int pipe_syscall = SYS_pipe;
  27 #else
  28 int pipe2_syscall = SYS_pipe2;
  29 #endif
  30 int write_syscall = SYS_write;
  31 #if defined(__arm__)
  32 /* Although 123456789 is an illegal syscall umber on arm linux, kernel
  33    sends SIGILL rather than returns -ENOSYS.  However, arm linux kernel
  34    returns -ENOSYS if syscall number is within 0xf0001..0xf07ff, so we
  35    can use 0xf07ff for unknown_syscall in test.  */
  36 int unknown_syscall = 0x0f07ff;
  37 #else
  38 int unknown_syscall = 123456789;
  39 #endif
  40 int exit_group_syscall = SYS_exit_group;
  41
  42 /* Set by the test when it wants execve.  */
  43 int do_execve = 0;
  44
  45 int
  46 main (int argc, char *const argv[])
  47 {
  48         int fd[2];
  49         char buf1[2] = "a";
  50         char buf2[2];
  51
  52         /* Test a simple self-exec, but only on request.  */
  53         if (do_execve)
  54           execv (*argv, argv);
  55
  56         /* A close() with a wrong argument.  We are only
  57            interested in the syscall.  */
  58         close (-1);
  59
  60         chroot (".");
  61
  62         pipe (fd);
  63
  64         write (fd[1], buf1, sizeof (buf1));
  65         read (fd[0], buf2, sizeof (buf2));
  66
  67         /* Test vfork-event interactions.  Child exits immediately.
  68            (Plain fork won't work on no-mmu kernel configurations.)  */
  69         if (vfork () == 0)
  70           _exit (0);
  71
  72         /* Trigger an intentional ENOSYS.  */
  73         syscall (unknown_syscall);
  74
  75         /* The last syscall.  Do not change this.  */
  76         _exit (0);
  77 }