| 1 | /* |
| 2 | * Copyright (C) - 2018 Francis Deslauriers <francis.deslauriers@efficios.com> |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU Lesser General Public License as published by the |
| 6 | * Free Software Foundation; version 2.1 of the License. |
| 7 | * |
| 8 | * This library is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License |
| 11 | * for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU Lesser General Public License |
| 14 | * along with this library; if not, write to the Free Software Foundation, |
| 15 | * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 16 | */ |
| 17 | |
| 18 | #include <dlfcn.h> |
| 19 | #include <stdio.h> |
| 20 | #include <stdlib.h> |
| 21 | #include <unistd.h> |
| 22 | #include <popt.h> |
| 23 | |
| 24 | #if HAS_CALLSITES |
| 25 | #include "callsites.h" |
| 26 | #endif |
| 27 | |
| 28 | void exec_callsite() |
| 29 | { |
| 30 | #if HAS_CALLSITES |
| 31 | call_tracepoint(); |
| 32 | #endif |
| 33 | } |
| 34 | |
| 35 | void print_list(void) |
| 36 | { |
| 37 | fprintf(stderr, "Test list (-t X):\n"); |
| 38 | fprintf(stderr, "\t0: dlopen() all libraries pass in arguments and execute " |
| 39 | "the callsite.\n"); |
| 40 | fprintf(stderr, "\t1: simulate the upgrade of a probe provider using dlopen() and dlclose(). \n"); |
| 41 | fprintf(stderr, "\t2: simulate the upgrade of a library containing the callsites using dlopen() and dlclose(). \n"); |
| 42 | } |
| 43 | |
| 44 | int dl_open_all(int nb_libraries, char **libraries) |
| 45 | { |
| 46 | int i, ret = 0; |
| 47 | void **handles; |
| 48 | |
| 49 | handles = malloc(nb_libraries * sizeof(void *)); |
| 50 | if (!handles) { |
| 51 | ret = -1; |
| 52 | goto error; |
| 53 | } |
| 54 | |
| 55 | /* Iterate over the libs to dlopen and save the handles. */ |
| 56 | for (i = 0; i < nb_libraries; i++) { |
| 57 | handles[i] = dlopen(libraries[i], RTLD_NOW); |
| 58 | if (!handles[i]) { |
| 59 | ret = -1; |
| 60 | goto error; |
| 61 | } |
| 62 | } |
| 63 | |
| 64 | exec_callsite(); |
| 65 | error: |
| 66 | free(handles); |
| 67 | return ret; |
| 68 | } |
| 69 | |
| 70 | /* |
| 71 | * Takes 2 paths to libraries, dlopen() the first, trace, dlopen() the second, |
| 72 | * and dlclose the first to simulate the upgrade of a library. |
| 73 | */ |
| 74 | int upgrade_lib(int nb_libraries, char **libraries) |
| 75 | { |
| 76 | int i, ret = 0; |
| 77 | void *handles[2]; |
| 78 | |
| 79 | if (nb_libraries != 2) { |
| 80 | ret = -1; |
| 81 | goto error; |
| 82 | } |
| 83 | |
| 84 | /* Iterate over the libs to dlopen and save the handles. */ |
| 85 | for (i = 0; i < nb_libraries; i++) { |
| 86 | handles[i] = dlopen(libraries[i], RTLD_NOW); |
| 87 | if (!handles[i]) { |
| 88 | ret = -1; |
| 89 | goto error; |
| 90 | } |
| 91 | |
| 92 | exec_callsite(); |
| 93 | } |
| 94 | |
| 95 | ret = dlclose(handles[0]); |
| 96 | if (ret) { |
| 97 | goto error; |
| 98 | } |
| 99 | |
| 100 | exec_callsite(); |
| 101 | |
| 102 | error: |
| 103 | return ret; |
| 104 | } |
| 105 | |
| 106 | /* |
| 107 | * Simulate the upgrade of a library containing a callsite. |
| 108 | * Receives two libraries containing callsites for the same tracepoint. |
| 109 | */ |
| 110 | int upgrade_callsite(int nb_libraries, char **libraries) |
| 111 | { |
| 112 | int ret = 0; |
| 113 | void *handles[2]; |
| 114 | void (*fct_ptr[2])(void); |
| 115 | |
| 116 | if (nb_libraries != 2) { |
| 117 | ret = -1; |
| 118 | goto error; |
| 119 | } |
| 120 | |
| 121 | /* Load the probes in the first library. */ |
| 122 | handles[0] = dlopen(libraries[0], RTLD_NOW); |
| 123 | if (!handles[0]) { |
| 124 | ret = -1; |
| 125 | goto error; |
| 126 | } |
| 127 | |
| 128 | /* |
| 129 | * Get the pointer to the old function containing the callsite and call it. |
| 130 | */ |
| 131 | fct_ptr[0] = dlsym(handles[0], "call_tracepoint"); |
| 132 | if (!fct_ptr[0]) { |
| 133 | ret = -1; |
| 134 | goto error; |
| 135 | } |
| 136 | fct_ptr[0](); |
| 137 | |
| 138 | /* Load the new callsite library. */ |
| 139 | handles[1] = dlopen(libraries[1], RTLD_NOW); |
| 140 | if (!handles[1]) { |
| 141 | ret = -1; |
| 142 | goto error; |
| 143 | } |
| 144 | |
| 145 | /* |
| 146 | * Get the pointer to the new function containing the callsite and call it. |
| 147 | */ |
| 148 | fct_ptr[1] = dlsym(handles[1], "call_tracepoint"); |
| 149 | if (!fct_ptr[1]) { |
| 150 | ret = -1; |
| 151 | goto error; |
| 152 | } |
| 153 | fct_ptr[1](); |
| 154 | |
| 155 | /* Unload the old callsite library. */ |
| 156 | ret = dlclose(handles[0]); |
| 157 | if (ret) { |
| 158 | goto error; |
| 159 | } |
| 160 | |
| 161 | /* Call the function containing the callsite in the new library. */ |
| 162 | fct_ptr[1](); |
| 163 | |
| 164 | ret = dlclose(handles[1]); |
| 165 | if (ret) { |
| 166 | goto error; |
| 167 | } |
| 168 | |
| 169 | error: |
| 170 | return ret; |
| 171 | } |
| 172 | |
| 173 | int main(int argc, const char **argv) |
| 174 | { |
| 175 | int c, ret = 0, test = -1, nb_libraries = 0; |
| 176 | char **libraries = NULL; |
| 177 | poptContext optCon; |
| 178 | struct poptOption optionsTable[] = { |
| 179 | { "test", 't', POPT_ARG_INT, &test, 0, "Test to run", NULL }, |
| 180 | { "list", 'l', 0, 0, 'l', "List of tests (-t X)", NULL }, |
| 181 | POPT_AUTOHELP |
| 182 | { NULL, 0, 0, NULL, 0 } |
| 183 | }; |
| 184 | |
| 185 | optCon = poptGetContext(NULL, argc, argv, optionsTable, 0); |
| 186 | if (argc < 2) { |
| 187 | poptPrintUsage(optCon, stderr, 0); |
| 188 | ret = -1; |
| 189 | goto error; |
| 190 | } |
| 191 | |
| 192 | while ((c = poptGetNextOpt(optCon)) >= 0) { |
| 193 | switch(c) { |
| 194 | case 'l': |
| 195 | print_list(); |
| 196 | goto error; |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | /* |
| 201 | * Populate the libraries array with the arguments passed to the process. |
| 202 | */ |
| 203 | while (poptPeekArg(optCon) != NULL) { |
| 204 | nb_libraries++; |
| 205 | libraries = realloc(libraries, nb_libraries * sizeof(char *)); |
| 206 | if (!libraries) { |
| 207 | ret = -1; |
| 208 | goto error; |
| 209 | } |
| 210 | libraries[nb_libraries - 1] = (char *) poptGetArg(optCon); |
| 211 | } |
| 212 | |
| 213 | switch(test) { |
| 214 | case 0: |
| 215 | #if HAS_CALLSITES |
| 216 | ret = dl_open_all(nb_libraries, libraries); |
| 217 | #else |
| 218 | fprintf(stderr, "Test not implemented for configuration " |
| 219 | "(HAS_CALLSITES=%d)\n", HAS_CALLSITES == 1); |
| 220 | #endif |
| 221 | break; |
| 222 | case 1: |
| 223 | #if HAS_CALLSITES |
| 224 | ret = upgrade_lib(nb_libraries, libraries); |
| 225 | #else |
| 226 | fprintf(stderr, "Test not implemented for configuration " |
| 227 | "(HAS_CALLSITES=%d)\n", HAS_CALLSITES == 1); |
| 228 | #endif |
| 229 | break; |
| 230 | case 2: |
| 231 | #if !HAS_CALLSITES |
| 232 | ret = upgrade_callsite(nb_libraries, libraries); |
| 233 | #else |
| 234 | fprintf(stderr, "Test not implemented for configuration " |
| 235 | "(HAS_CALLSITES=%d)\n", HAS_CALLSITES == 1); |
| 236 | #endif |
| 237 | break; |
| 238 | default: |
| 239 | fprintf(stderr, "Test %d not implemented\n", test); |
| 240 | ret = -1; |
| 241 | break; |
| 242 | } |
| 243 | error: |
| 244 | free(libraries); |
| 245 | poptFreeContext(optCon); |
| 246 | return ret; |
| 247 | } |