contrib/sendmail/libsm/t-sem.c

   1 /*
   2  * Copyright (c) 2000-2001, 2005-2008 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  *
   5  * By using this file, you agree to the terms and conditions set
   6  * forth in the LICENSE file which can be found at the top level of
   7  * the sendmail distribution.
   8  */
   9
  10 #include <sm/gen.h>
  11 SM_RCSID("@(#)$Id: t-sem.c,v 1.17 2008/05/30 16:26:38 ca Exp $")
  12
  13 #include <stdio.h>
  14
  15 #if SM_CONF_SEM
  16 # include <stdlib.h>
  17 # include <unistd.h>
  18 # include <sysexits.h>
  19 # include <sm/heap.h>
  20 # include <sm/string.h>
  21 # include <sm/signal.h>
  22 # include <sm/test.h>
  23 # include <sm/sem.h>
  24
  25 # define T_SM_SEM_KEY (4321L)
  26
  27 static void
  28 delay(t, s)
  29         int t;
  30         char *s;
  31 {
  32         if (t > 0)
  33         {
  34 #if DEBUG
  35                 fprintf(stderr, "sleep(%d) before %s\n", t, s);
  36 #endif /* DEBUG */
  37                 sleep(t);
  38         }
  39 #if DEBUG
  40         fprintf(stderr, "%s\n", s);
  41 #endif /* DEBUG */
  42 }
  43
  44
  45 /*
  46 **  SEMINTER -- interactive testing of semaphores.
  47 **
  48 **      Parameters:
  49 **              owner -- create semaphores.
  50 **
  51 **      Returns:
  52 **              0 on success
  53 **              < 0 on failure.
  54 */
  55
  56 static int
  57 seminter(owner)
  58         bool owner;
  59 {
  60         int semid;
  61         int t;
  62
  63         semid = sm_sem_start(T_SM_SEM_KEY, SM_NSEM, 0, owner);
  64         if (semid < 0)
  65         {
  66                 perror("sm_sem_start failed");
  67                 return 1;
  68         }
  69
  70         while ((t = getchar()) != EOF)
  71         {
  72                 switch (t)
  73                 {
  74                   case 'a':
  75                         delay(0, "try to acq");
  76                         if (sm_sem_acq(semid, 0, 2) < 0)
  77                         {
  78                                 perror("sm_sem_acq failed");
  79                                 return 1;
  80                         }
  81                         delay(0, "acquired");
  82                         break;
  83
  84                   case 'r':
  85                         delay(0, "try to rel");
  86                         if (sm_sem_rel(semid, 0, 2) < 0)
  87                         {
  88                                 perror("sm_sem_rel failed");
  89                                 return 1;
  90                         }
  91                         delay(0, "released");
  92                         break;
  93
  94                   case 'v':
  95                         if ((t = sm_sem_get(semid, 0)) < 0)
  96                         {
  97                                 perror("get_sem failed");
  98                                 return 1;
  99                         }
 100                         printf("semval: %d\n", t);
 101                         break;
 102
 103                 }
 104         }
 105         if (owner)
 106                 return sm_sem_stop(semid);
 107         return 0;
 108 }
 109
 110 /*
 111 **  SEM_CLEANUP -- cleanup if something breaks
 112 **
 113 **      Parameters:
 114 **              sig -- signal.
 115 **
 116 **      Returns:
 117 **              none.
 118 */
 119
 120 static int semid_c = -1;
 121 void
 122 sem_cleanup(sig)
 123         int sig;
 124 {
 125         if (semid_c >= 0)
 126                 (void) sm_sem_stop(semid_c);
 127         exit(EX_UNAVAILABLE);
 128 }
 129
 130 static int
 131 drop_priv(uid, gid)
 132         uid_t uid;
 133         gid_t gid;
 134 {
 135         int r;
 136
 137         r = setgid(gid);
 138         if (r != 0)
 139                 return r;
 140         r = setuid(uid);
 141         return r;
 142 }
 143
 144 /*
 145 **  SEMTEST -- test of semaphores
 146 **
 147 **      Parameters:
 148 **              owner -- create semaphores.
 149 **
 150 **      Returns:
 151 **              0 on success
 152 **              < 0 on failure.
 153 */
 154
 155 # define MAX_CNT        10
 156
 157 static int
 158 semtest(owner, uid, gid)
 159         int owner;
 160         uid_t uid;
 161         gid_t gid;
 162 {
 163         int semid, r;
 164         int cnt = 0;
 165
 166         if (!owner && uid != 0)
 167         {
 168                 r = drop_priv(uid, gid);
 169                 if (r < 0)
 170                 {
 171                         perror("drop_priv child failed");
 172                         return -1;
 173                 }
 174         }
 175         semid = sm_sem_start(T_SM_SEM_KEY, 1, 0, owner);
 176         if (semid < 0)
 177         {
 178                 perror("sm_sem_start failed");
 179                 return -1;
 180         }
 181
 182         if (owner)
 183         {
 184                 if (uid != 0)
 185                 {
 186                         r = sm_semsetowner(semid, uid, gid, 0660);
 187                         if (r < 0)
 188                         {
 189                                 perror("sm_semsetowner failed");
 190                                 return -1;
 191                         }
 192                         r = drop_priv(uid, gid);
 193                         if (r < 0)
 194                         {
 195                                 perror("drop_priv owner failed");
 196                                 return -1;
 197                         }
 198                 }
 199
 200                 /* just in case someone kills the program... */
 201                 semid_c = semid;
 202                 (void) sm_signal(SIGHUP, sem_cleanup);
 203                 (void) sm_signal(SIGINT, sem_cleanup);
 204                 (void) sm_signal(SIGTERM, sem_cleanup);
 205
 206                 delay(1, "parent: acquire 1");
 207                 cnt = 0;
 208                 do
 209                 {
 210                         r = sm_sem_acq(semid, 0, 0);
 211                         if (r < 0)
 212                         {
 213                                 sleep(1);
 214                                 ++cnt;
 215                         }
 216                 } while (r < 0 && cnt <= MAX_CNT);
 217                 SM_TEST(r >= 0);
 218                 if (r < 0)
 219                         return r;
 220
 221                 delay(3, "parent: release 1");
 222                 cnt = 0;
 223                 do
 224                 {
 225                         r = sm_sem_rel(semid, 0, 0);
 226                         if (r < 0)
 227                         {
 228                                 sleep(1);
 229                                 ++cnt;
 230                         }
 231                 } while (r < 0 && cnt <= MAX_CNT);
 232                 SM_TEST(r >= 0);
 233                 if (r < 0)
 234                         return r;
 235
 236                 delay(1, "parent: getval");
 237                 cnt = 0;
 238                 do
 239                 {
 240                         r = sm_sem_get(semid, 0);
 241                         if (r <= 0)
 242                         {
 243                                 sleep(1);
 244                                 ++cnt;
 245                         }
 246                 } while (r <= 0 && cnt <= MAX_CNT);
 247                 SM_TEST(r > 0);
 248                 if (r <= 0)
 249                         return r;
 250
 251                 delay(1, "parent: acquire 2");
 252                 cnt = 0;
 253                 do
 254                 {
 255                         r = sm_sem_acq(semid, 0, 0);
 256                         if (r < 0)
 257                         {
 258                                 sleep(1);
 259                                 ++cnt;
 260                         }
 261                 } while (r < 0 && cnt <= MAX_CNT);
 262                 SM_TEST(r >= 0);
 263                 if (r < 0)
 264                         return r;
 265
 266                 cnt = 0;
 267                 do
 268                 {
 269                         r = sm_sem_rel(semid, 0, 0);
 270                         if (r < 0)
 271                         {
 272                                 sleep(1);
 273                                 ++cnt;
 274                         }
 275                 } while (r < 0 && cnt <= MAX_CNT);
 276                 SM_TEST(r >= 0);
 277                 if (r < 0)
 278                         return r;
 279         }
 280         else
 281         {
 282                 delay(1, "child: acquire 1");
 283                 cnt = 0;
 284                 do
 285                 {
 286                         r = sm_sem_acq(semid, 0, 0);
 287                         if (r < 0)
 288                         {
 289                                 sleep(1);
 290                                 ++cnt;
 291                         }
 292                 } while (r < 0 && cnt <= MAX_CNT);
 293                 SM_TEST(r >= 0);
 294                 if (r < 0)
 295                         return r;
 296
 297                 delay(1, "child: release 1");
 298                 cnt = 0;
 299                 do
 300                 {
 301                         r = sm_sem_rel(semid, 0, 0);
 302                         if (r < 0)
 303                         {
 304                                 sleep(1);
 305                                 ++cnt;
 306                         }
 307                 } while (r < 0 && cnt <= MAX_CNT);
 308                 SM_TEST(r >= 0);
 309                 if (r < 0)
 310                         return r;
 311
 312         }
 313         if (owner)
 314                 return sm_sem_stop(semid);
 315         return 0;
 316 }
 317
 318 int
 319 main(argc, argv)
 320         int argc;
 321         char *argv[];
 322 {
 323         bool interactive = false;
 324         bool owner = false;
 325         int ch, r;
 326         uid_t uid;
 327         gid_t gid;
 328
 329         uid = 0;
 330         gid = 0;
 331         r = 0;
 332
 333 # define OPTIONS        "iog:u:"
 334         while ((ch = getopt(argc, argv, OPTIONS)) != -1)
 335         {
 336                 switch ((char) ch)
 337                 {
 338                   case 'g':
 339                         gid = (gid_t)strtoul(optarg, 0, 0);
 340                         break;
 341
 342                   case 'i':
 343                         interactive = true;
 344                         break;
 345
 346                   case 'u':
 347                         uid = (uid_t)strtoul(optarg, 0, 0);
 348                         break;
 349
 350                   case 'o':
 351                         owner = true;
 352                         break;
 353
 354                   default:
 355                         break;
 356                 }
 357         }
 358
 359         if (interactive)
 360                 r = seminter(owner);
 361         else
 362         {
 363                 pid_t pid;
 364
 365                 printf("This test takes about 8 seconds.\n");
 366                 printf("If it takes longer than 30 seconds, please interrupt it\n");
 367                 printf("and compile again without semaphore support, i.e.,");
 368                 printf("-DSM_CONF_SEM=0\n");
 369                 if ((pid = fork()) < 0)
 370                 {
 371                         perror("fork failed\n");
 372                         return -1;
 373                 }
 374
 375                 sm_test_begin(argc, argv, "test semaphores");
 376                 if (pid == 0)
 377                 {
 378                         /* give the parent the chance to setup data */
 379                         sleep(1);
 380                         r = semtest(false, uid, gid);
 381                 }
 382                 else
 383                 {
 384                         r = semtest(true, uid, gid);
 385                 }
 386                 SM_TEST(r == 0);
 387                 return sm_test_end();
 388         }
 389         return r;
 390 }
 391 #else /* SM_CONF_SEM */
 392 int
 393 main(argc, argv)
 394         int argc;
 395         char *argv[];
 396 {
 397         printf("No support for semaphores configured on this machine\n");
 398         return 0;
 399 }
 400 #endif /* SM_CONF_SEM */