tests/utils/testapp/userspace-probe-sdt-binary/userspace-probe-sdt-binary.c

   1 /*
   2  * Copyright (C) 2017  Francis Deslauriers <francis.deslauriers@efficios.com>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  17  */
  18 #ifndef _GNU_SOURCE
  19 #define _GNU_SOURCE
  20 #endif
  21
  22 #include <dlfcn.h>
  23 #include <fcntl.h>
  24 #include <stdbool.h>
  25 #include <stdint.h>
  26 #include <stdio.h>
  27 #include <sys/stat.h>
  28 #include <sys/types.h>
  29
  30 #include <sys/sdt.h>
  31
  32 #include "foobar_provider.h"
  33 #include "libfoo.h"
  34 #include "sema.h"
  35
  36 int main(int argc, char *argv[])
  37 {
  38         void *handle;
  39         void (*bar_function)();
  40
  41         FOOBAR_TP1();
  42         FOOBAR_TP2();
  43         /*
  44          * This SDT tracepoint has an argument. Argument extraction is not support
  45          * at the moment but tracing of the tracepoint should work.
  46          */
  47         FOOBAR_TP_WITH_ARG(42);
  48
  49         /* Call function containing an SDT tracepoint in shared object */
  50         foo_function();
  51
  52         /*
  53          * Load a show shared object and call a function containing an SDT
  54          * tracepoint
  55          */
  56         handle = dlopen("libbar.so", RTLD_LAZY);
  57         if (!handle) {
  58                 fprintf(stderr, "Can't dlopen libbar.so");
  59                 return -1;
  60         }
  61         bar_function = (void (*)())dlsym(handle, "bar_function");
  62         bar_function();
  63         dlclose(handle);
  64
  65         /* This tracepoint has 2 callsites in this binary */
  66         FOOBAR_TP2();
  67
  68         /*
  69          * This function is defined in libfoo AND in libzzz. For a test, libzzz is
  70          * LD_PRELOADed and should override this function
  71          */
  72         overridable_function();
  73
  74         /*
  75          * This function is calling a SDT tracepoint that is guarded by a
  76          * semaphore.
  77          */
  78         sema_function();
  79         return 0;
  80 }
  81