tests/regression/ust/multi-lib/multi-lib-test.c

   1 /*
   2  * Copyright (C) 2018 Francis Deslauriers <francis.deslauriers@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #include <dlfcn.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12 #include <popt.h>
  13
  14 #if HAS_CALLSITES
  15 #include "callsites.h"
  16 #endif
  17
  18 void exec_callsite()
  19 {
  20 #if HAS_CALLSITES
  21         call_tracepoint();
  22 #endif
  23 }
  24
  25 void print_list(void)
  26 {
  27         fprintf(stderr, "Test list (-t X):\n");
  28         fprintf(stderr, "\t0: dlopen() all libraries pass in arguments and execute "
  29                         "the callsite.\n");
  30         fprintf(stderr, "\t1: simulate the upgrade of a probe provider using dlopen() and dlclose(). \n");
  31         fprintf(stderr, "\t2: simulate the upgrade of a library containing the callsites using dlopen() and dlclose(). \n");
  32 }
  33
  34 int dl_open_all(int nb_libraries, char **libraries)
  35 {
  36         int i, ret = 0;
  37         void **handles;
  38
  39         handles = malloc(nb_libraries * sizeof(void *));
  40         if (!handles) {
  41                 ret = -1;
  42                 goto error;
  43         }
  44
  45         /* Iterate over the libs to dlopen and save the handles. */
  46         for (i = 0; i < nb_libraries; i++) {
  47                 handles[i] = dlopen(libraries[i], RTLD_NOW);
  48                 if (!handles[i]) {
  49                         ret = -1;
  50                         goto error;
  51                 }
  52         }
  53
  54         exec_callsite();
  55 error:
  56         free(handles);
  57         return ret;
  58 }
  59
  60 /*
  61  * Takes 2 paths to libraries, dlopen() the first, trace, dlopen() the second,
  62  * and dlclose the first to simulate the upgrade of a library.
  63  */
  64 int upgrade_lib(int nb_libraries, char **libraries)
  65 {
  66         int i, ret = 0;
  67         void *handles[2];
  68
  69         if (nb_libraries != 2) {
  70                 ret = -1;
  71                 goto error;
  72         }
  73
  74         /* Iterate over the libs to dlopen and save the handles. */
  75         for (i = 0; i < nb_libraries; i++) {
  76                 handles[i] = dlopen(libraries[i], RTLD_NOW);
  77                 if (!handles[i]) {
  78                         ret = -1;
  79                         goto error;
  80                 }
  81
  82                 exec_callsite();
  83         }
  84
  85         ret = dlclose(handles[0]);
  86         if (ret) {
  87                 goto error;
  88         }
  89
  90         exec_callsite();
  91
  92 error:
  93         return ret;
  94 }
  95
  96 /*
  97  * Simulate the upgrade of a library containing a callsite.
  98  * Receives two libraries containing callsites for the same tracepoint.
  99  */
 100 int upgrade_callsite(int nb_libraries, char **libraries)
 101 {
 102         int ret = 0;
 103         void *handles[2];
 104         void (*fct_ptr[2])(void);
 105
 106         if (nb_libraries != 2) {
 107                 ret = -1;
 108                 goto error;
 109         }
 110
 111         /* Load the probes in the first library. */
 112         handles[0] = dlopen(libraries[0], RTLD_NOW);
 113         if (!handles[0]) {
 114                 ret = -1;
 115                 goto error;
 116         }
 117
 118         /*
 119          * Get the pointer to the old function containing the callsite and call it.
 120          */
 121         fct_ptr[0] = dlsym(handles[0], "call_tracepoint");
 122         if (!fct_ptr[0]) {
 123                 ret = -1;
 124                 goto error;
 125         }
 126         fct_ptr[0]();
 127
 128         /* Load the new callsite library. */
 129         handles[1] = dlopen(libraries[1], RTLD_NOW);
 130         if (!handles[1]) {
 131                 ret = -1;
 132                 goto error;
 133         }
 134
 135         /*
 136          * Get the pointer to the new function containing the callsite and call it.
 137          */
 138         fct_ptr[1] = dlsym(handles[1], "call_tracepoint");
 139         if (!fct_ptr[1]) {
 140                 ret = -1;
 141                 goto error;
 142         }
 143         fct_ptr[1]();
 144
 145         /* Unload the old callsite library. */
 146         ret = dlclose(handles[0]);
 147         if (ret) {
 148                 goto error;
 149         }
 150
 151         /* Call the function containing the callsite in the new library. */
 152         fct_ptr[1]();
 153
 154         ret = dlclose(handles[1]);
 155         if (ret) {
 156                 goto error;
 157         }
 158
 159 error:
 160         return ret;
 161 }
 162
 163 int main(int argc, const char **argv)
 164 {
 165         int c, ret = 0, test = -1, nb_libraries = 0;
 166         char **libraries = NULL;
 167         poptContext optCon;
 168         struct poptOption optionsTable[] = {
 169                         { "test", 't', POPT_ARG_INT, &test, 0, "Test to run", NULL },
 170                         { "list", 'l', 0, 0, 'l', "List of tests (-t X)", NULL },
 171                         POPT_AUTOHELP
 172                         { NULL, 0, 0, NULL, 0 }
 173         };
 174
 175         optCon = poptGetContext(NULL, argc, argv, optionsTable, 0);
 176         if (argc < 2) {
 177                 poptPrintUsage(optCon, stderr, 0);
 178                 ret = -1;
 179                 goto error;
 180         }
 181
 182         while ((c = poptGetNextOpt(optCon)) >= 0) {
 183                 switch(c) {
 184                 case 'l':
 185                         print_list();
 186                         goto error;
 187                 }
 188         }
 189
 190         /*
 191          * Populate the libraries array with the arguments passed to the process.
 192          */
 193         while (poptPeekArg(optCon) != NULL) {
 194                 char **realloced_libraries = NULL;
 195
 196                 nb_libraries++;
 197                 realloced_libraries = realloc(libraries, nb_libraries * sizeof(char *));
 198                 if (!realloced_libraries) {
 199                         ret = -1;
 200                         goto error;
 201                 }
 202                 libraries = realloced_libraries;
 203                 libraries[nb_libraries - 1] = (char *) poptGetArg(optCon);
 204         }
 205
 206         switch(test) {
 207         case 0:
 208 #if HAS_CALLSITES
 209                 ret = dl_open_all(nb_libraries, libraries);
 210 #else
 211                 fprintf(stderr, "Test not implemented for configuration "
 212                                 "(HAS_CALLSITES=%d)\n", HAS_CALLSITES == 1);
 213 #endif
 214                 break;
 215         case 1:
 216 #if HAS_CALLSITES
 217                 ret = upgrade_lib(nb_libraries, libraries);
 218 #else
 219                 fprintf(stderr, "Test not implemented for configuration "
 220                                 "(HAS_CALLSITES=%d)\n", HAS_CALLSITES == 1);
 221 #endif
 222                 break;
 223         case 2:
 224 #if !HAS_CALLSITES
 225                 ret = upgrade_callsite(nb_libraries, libraries);
 226 #else
 227                 fprintf(stderr, "Test not implemented for configuration "
 228                                 "(HAS_CALLSITES=%d)\n", HAS_CALLSITES == 1);
 229 #endif
 230                 break;
 231         default:
 232                 fprintf(stderr, "Test %d not implemented\n", test);
 233                 ret = -1;
 234                 break;
 235         }
 236 error:
 237         free(libraries);
 238         poptFreeContext(optCon);
 239         return ret;
 240 }