git.ozlabs.org Git - ccan/blob - ccan/tdb/tools/replay_trace.c

   1 #include <ccan/tdb/tdb.h>
   2 #include <ccan/grab_file/grab_file.h>
   3 #include <ccan/hash/hash.h>
   4 #include <ccan/talloc/talloc.h>
   5 #include <ccan/str_talloc/str_talloc.h>
   6 #include <ccan/str/str.h>
   7 #include <ccan/list/list.h>
   8 #include <err.h>
   9 #include <ctype.h>
  10 #include <string.h>
  11 #include <unistd.h>
  12 #include <sys/types.h>
  13 #include <sys/wait.h>
  14 #include <sys/time.h>
  15 #include <errno.h>
  16 #include <signal.h>
  17 #include <assert.h>
  18
  19 #define STRINGIFY2(x) #x
  20 #define STRINGIFY(x) STRINGIFY2(x)
  21
  22 /* Avoid mod by zero */
  23 static unsigned int total_keys = 1;
  24
  25 /* #define DEBUG_DEPS 1 */
  26
  27 /* Traversals block transactions in the current implementation. */
  28 #define TRAVERSALS_TAKE_TRANSACTION_LOCK 1
  29
  30 struct pipe {
  31         int fd[2];
  32 };
  33 static struct pipe *pipes;
  34
  35 static void __attribute__((noreturn)) fail(const char *filename,
  36                                            unsigned int line,
  37                                            const char *fmt, ...)
  38 {
  39         va_list ap;
  40
  41         va_start(ap, fmt);
  42         fprintf(stderr, "%s:%u: FAIL: ", filename, line);
  43         vfprintf(stderr, fmt, ap);
  44         fprintf(stderr, "\n");
  45         va_end(ap);
  46         exit(1);
  47 }
  48
  49 /* Try or die. */
  50 #define try(expr, expect)                                               \
  51         do {                                                            \
  52                 int ret = (expr);                                       \
  53                 if (ret != (expect))                                    \
  54                         fail(filename[file], i+1,                       \
  55                              STRINGIFY(expr) "= %i", ret);              \
  56         } while (0)
  57
  58 /* Try or imitate results. */
  59 #define unreliable(expr, expect, force, undo)                           \
  60         do {                                                            \
  61                 int ret = expr;                                         \
  62                 if (ret != expect) {                                    \
  63                         fprintf(stderr, "%s:%u: %s gave %i not %i",     \
  64                                 filename[file], i+1, STRINGIFY(expr),   \
  65                                 ret, expect);                           \
  66                         if (expect == 0)                                \
  67                                 force;                                  \
  68                         else                                            \
  69                                 undo;                                   \
  70                 }                                                       \
  71         } while (0)
  72
  73 static bool key_eq(TDB_DATA a, TDB_DATA b)
  74 {
  75         if (a.dsize != b.dsize)
  76                 return false;
  77         return memcmp(a.dptr, b.dptr, a.dsize) == 0;
  78 }
  79
  80 /* This is based on the hash algorithm from gdbm */
  81 static unsigned int hash_key(TDB_DATA *key)
  82 {
  83         uint32_t value; /* Used to compute the hash value.  */
  84         uint32_t   i;   /* Used to cycle through random values. */
  85
  86         /* Set the initial value from the key size. */
  87         for (value = 0x238F13AF ^ key->dsize, i=0; i < key->dsize; i++)
  88                 value = (value + (key->dptr[i] << (i*5 % 24)));
  89
  90         return (1103515243 * value + 12345);
  91 }
  92
  93 enum op_type {
  94         OP_TDB_LOCKALL,
  95         OP_TDB_LOCKALL_MARK,
  96         OP_TDB_LOCKALL_UNMARK,
  97         OP_TDB_LOCKALL_NONBLOCK,
  98         OP_TDB_UNLOCKALL,
  99         OP_TDB_LOCKALL_READ,
 100         OP_TDB_LOCKALL_READ_NONBLOCK,
 101         OP_TDB_UNLOCKALL_READ,
 102         OP_TDB_CHAINLOCK,
 103         OP_TDB_CHAINLOCK_NONBLOCK,
 104         OP_TDB_CHAINLOCK_MARK,
 105         OP_TDB_CHAINLOCK_UNMARK,
 106         OP_TDB_CHAINUNLOCK,
 107         OP_TDB_CHAINLOCK_READ,
 108         OP_TDB_CHAINUNLOCK_READ,
 109         OP_TDB_PARSE_RECORD,
 110         OP_TDB_EXISTS,
 111         OP_TDB_STORE,
 112         OP_TDB_APPEND,
 113         OP_TDB_GET_SEQNUM,
 114         OP_TDB_WIPE_ALL,
 115         OP_TDB_TRANSACTION_START,
 116         OP_TDB_TRANSACTION_CANCEL,
 117         OP_TDB_TRANSACTION_COMMIT,
 118         OP_TDB_TRAVERSE_READ_START,
 119         OP_TDB_TRAVERSE_START,
 120         OP_TDB_TRAVERSE_END,
 121         OP_TDB_TRAVERSE,
 122         OP_TDB_FIRSTKEY,
 123         OP_TDB_NEXTKEY,
 124         OP_TDB_FETCH,
 125         OP_TDB_DELETE,
 126 };
 127
 128 struct op {
 129         unsigned int serial;
 130         enum op_type op;
 131         TDB_DATA key;
 132         TDB_DATA data;
 133         int ret;
 134
 135         /* Who is waiting for us? */
 136         struct list_head post;
 137         /* What are we waiting for? */
 138         struct list_head pre;
 139
 140         /* If I'm part of a group (traverse/transaction) where is
 141          * start?  (Otherwise, 0) */
 142         unsigned int group_start;
 143
 144         union {
 145                 int flag; /* open and store */
 146                 struct traverse *trav; /* traverse start */
 147                 struct {  /* append */
 148                         TDB_DATA pre;
 149                         TDB_DATA post;
 150                 } append;
 151                 unsigned int transaction_end; /* transaction start */
 152         };
 153 };
 154
 155 static unsigned char hex_char(const char *filename, unsigned int line, char c)
 156 {
 157         c = toupper(c);
 158         if (c >= 'A' && c <= 'F')
 159                 return c - 'A' + 10;
 160         if (c >= '0' && c <= '9')
 161                 return c - '0';
 162         fail(filename, line, "invalid hex character '%c'", c);
 163 }
 164
 165 /* TDB data is <size>:<%02x>* */
 166 static TDB_DATA make_tdb_data(const void *ctx,
 167                               const char *filename, unsigned int line,
 168                               const char *word)
 169 {
 170         TDB_DATA data;
 171         unsigned int i;
 172         const char *p;
 173
 174         if (streq(word, "NULL"))
 175                 return tdb_null;
 176
 177         data.dsize = atoi(word);
 178         data.dptr = talloc_array(ctx, unsigned char, data.dsize);
 179         p = strchr(word, ':');
 180         if (!p)
 181                 fail(filename, line, "invalid tdb data '%s'", word);
 182         p++;
 183         for (i = 0; i < data.dsize; i++)
 184                 data.dptr[i] = hex_char(filename, line, p[i*2])*16
 185                         + hex_char(filename, line, p[i*2+1]);
 186
 187         return data;
 188 }
 189
 190 static void add_op(const char *filename, struct op **op, unsigned int i,
 191                    unsigned int serial, enum op_type type)
 192 {
 193         struct op *new;
 194         *op = talloc_realloc(NULL, *op, struct op, i+1);
 195         new = (*op) + i;
 196         new->op = type;
 197         new->serial = serial;
 198         new->ret = 0;
 199         new->group_start = 0;
 200 }
 201
 202 static void op_add_nothing(const char *filename,
 203                            struct op op[], unsigned int op_num, char *words[])
 204 {
 205         if (words[2])
 206                 fail(filename, op_num+1, "Expected no arguments");
 207         op[op_num].key = tdb_null;
 208 }
 209
 210 static void op_add_key(const char *filename,
 211                        struct op op[], unsigned int op_num, char *words[])
 212 {
 213         if (words[2] == NULL || words[3])
 214                 fail(filename, op_num+1, "Expected just a key");
 215
 216         op[op_num].key = make_tdb_data(op, filename, op_num+1, words[2]);
 217         if (op[op_num].op != OP_TDB_TRAVERSE)
 218                 total_keys++;
 219 }
 220
 221 static void op_add_key_ret(const char *filename,
 222                            struct op op[], unsigned int op_num, char *words[])
 223 {
 224         if (!words[2] || !words[3] || !words[4] || words[5]
 225             || !streq(words[3], "="))
 226                 fail(filename, op_num+1, "Expected <key> = <ret>");
 227         op[op_num].ret = atoi(words[4]);
 228         op[op_num].key = make_tdb_data(op, filename, op_num+1, words[2]);
 229         /* May only be a unique key if it fails */
 230         if (op[op_num].ret != 0)
 231                 total_keys++;
 232 }
 233
 234 static void op_add_key_data(const char *filename,
 235                             struct op op[], unsigned int op_num, char *words[])
 236 {
 237         if (!words[2] || !words[3] || !words[4] || words[5]
 238             || !streq(words[3], "="))
 239                 fail(filename, op_num+1, "Expected <key> = <data>");
 240         op[op_num].key = make_tdb_data(op, filename, op_num+1, words[2]);
 241         op[op_num].data = make_tdb_data(op, filename, op_num+1, words[4]);
 242         /* May only be a unique key if it fails */
 243         if (!op[op_num].data.dptr)
 244                 total_keys++;
 245 }
 246
 247 /* <serial> tdb_store <rec> <rec> <flag> = <ret> */
 248 static void op_add_store(const char *filename,
 249                          struct op op[], unsigned int op_num, char *words[])
 250 {
 251         if (!words[2] || !words[3] || !words[4] || !words[5] || !words[6]
 252             || words[7] || !streq(words[5], "="))
 253                 fail(filename, op_num+1, "Expect <key> <data> <flag> = <ret>");
 254
 255         op[op_num].flag = strtoul(words[4], NULL, 0);
 256         op[op_num].ret = atoi(words[6]);
 257         op[op_num].key = make_tdb_data(op, filename, op_num+1, words[2]);
 258         op[op_num].data = make_tdb_data(op, filename, op_num+1, words[3]);
 259         total_keys++;
 260 }
 261
 262 /* <serial> tdb_append <rec> <rec> = <rec> */
 263 static void op_add_append(const char *filename,
 264                           struct op op[], unsigned int op_num, char *words[])
 265 {
 266         if (!words[2] || !words[3] || !words[4] || !words[5] || words[6]
 267             || !streq(words[4], "="))
 268                 fail(filename, op_num+1, "Expect <key> <data> = <rec>");
 269
 270         op[op_num].key = make_tdb_data(op, filename, op_num+1, words[2]);
 271         op[op_num].data = make_tdb_data(op, filename, op_num+1, words[3]);
 272
 273         op[op_num].append.post
 274                 = make_tdb_data(op, filename, op_num+1, words[5]);
 275
 276         /* By subtraction, figure out what previous data was. */
 277         op[op_num].append.pre.dptr = op[op_num].append.post.dptr;
 278         op[op_num].append.pre.dsize
 279                 = op[op_num].append.post.dsize - op[op_num].data.dsize;
 280         total_keys++;
 281 }
 282
 283 /* <serial> tdb_get_seqnum = <ret> */
 284 static void op_add_seqnum(const char *filename,
 285                           struct op op[], unsigned int op_num, char *words[])
 286 {
 287         if (!words[2] || !words[3] || words[4] || !streq(words[2], "="))
 288                 fail(filename, op_num+1, "Expect = <ret>");
 289
 290         op[op_num].key = tdb_null;
 291         op[op_num].ret = atoi(words[3]);
 292 }
 293
 294 static void op_add_traverse(const char *filename,
 295                             struct op op[], unsigned int op_num, char *words[])
 296 {
 297         if (words[2])
 298                 fail(filename, op_num+1, "Expect no arguments");
 299
 300         op[op_num].key = tdb_null;
 301         op[op_num].trav = NULL;
 302 }
 303
 304 static void op_add_transaction(const char *filename, struct op op[],
 305                                unsigned int op_num, char *words[])
 306 {
 307         if (words[2])
 308                 fail(filename, op_num+1, "Expect no arguments");
 309
 310         op[op_num].key = tdb_null;
 311         op[op_num].transaction_end = 0;
 312 }
 313
 314 static void op_analyze_transaction(const char *filename,
 315                                    struct op op[], unsigned int op_num,
 316                                    char *words[])
 317 {
 318         int i, start;
 319
 320         op[op_num].key = tdb_null;
 321
 322         if (words[2])
 323                 fail(filename, op_num+1, "Expect no arguments");
 324
 325         for (i = op_num-1; i >= 0; i--) {
 326                 if (op[i].op == OP_TDB_TRANSACTION_START &&
 327                     !op[i].transaction_end)
 328                         break;
 329         }
 330
 331         if (i < 0)
 332                 fail(filename, op_num+1, "no transaction start found");
 333
 334         start = i;
 335         op[start].transaction_end = op_num;
 336
 337         /* This rolls in nested transactions.  I think that's right. */
 338         for (i++; i <= op_num; i++)
 339                 op[i].group_start = start;
 340 }
 341
 342 struct traverse_hash {
 343         TDB_DATA key;
 344         unsigned int index;
 345 };
 346
 347 /* A traverse is a hash of keys, each one associated with ops. */
 348 struct traverse {
 349         /* How many traversal callouts should I do? */
 350         unsigned int num;
 351
 352         /* Where is traversal end op? */
 353         unsigned int end;
 354
 355         /* For trivial traversals. */
 356         struct traverse_hash *hash;
 357 };
 358
 359 /* A trivial traversal is one which doesn't terminate early and only
 360  * plays with its own record.  We can reliably replay these even if
 361  * traverse order changes. */
 362 static bool is_trivial_traverse(struct op op[], unsigned int end)
 363 {
 364 #if 0
 365         unsigned int i;
 366         TDB_DATA cur = tdb_null;
 367
 368         if (op[end].ret != 0)
 369                 return false;
 370
 371         for (i = 0; i < end; i++) {
 372                 if (!op[i].key.dptr)
 373                         continue;
 374                 if (op[i].op == OP_TDB_TRAVERSE)
 375                         cur = op[i].key;
 376                 if (!key_eq(cur, op[i].key))
 377                         return false;
 378         }
 379         return true;
 380 #endif
 381         /* With multiple things happening at once, no traverse is trivial. */
 382         return false;
 383 }
 384
 385 static void op_analyze_traverse(const char *filename,
 386                                 struct op op[], unsigned int op_num,
 387                                 char *words[])
 388 {
 389         int i, start;
 390         struct traverse *trav = talloc(op, struct traverse);
 391
 392         op[op_num].key = tdb_null;
 393
 394         /* = %u means traverse function terminated. */
 395         if (words[2]) {
 396                 if (!streq(words[2], "=") || !words[3] || words[4])
 397                         fail(filename, op_num+1, "expect = <num>");
 398                 op[op_num].ret = atoi(words[3]);
 399         } else
 400                 op[op_num].ret = 0;
 401
 402         trav->num = 0;
 403         trav->end = op_num;
 404         for (i = op_num-1; i >= 0; i--) {
 405                 if (op[i].op == OP_TDB_TRAVERSE)
 406                         trav->num++;
 407                 if (op[i].op != OP_TDB_TRAVERSE_READ_START
 408                     && op[i].op != OP_TDB_TRAVERSE_START)
 409                         continue;
 410                 if (op[i].trav)
 411                         continue;
 412                 break;
 413         }
 414
 415         if (i < 0)
 416                 fail(filename, op_num+1, "no traversal start found");
 417
 418         start = i;
 419         op[start].trav = trav;
 420
 421         for (i = start; i <= op_num; i++)
 422                 op[i].group_start = start;
 423
 424         if (is_trivial_traverse(op+i, op_num-i)) {
 425                 /* Fill in a plentiful hash table. */
 426                 op[start].trav->hash = talloc_zero_array(op[i].trav,
 427                                                          struct traverse_hash,
 428                                                          trav->num * 2);
 429                 for (i = start; i < op_num; i++) {
 430                         unsigned int h;
 431                         if (op[i].op != OP_TDB_TRAVERSE)
 432                                 continue;
 433                         h = hash_key(&op[i].key) % (trav->num * 2);
 434                         while (trav->hash[h].index)
 435                                 h = (h + 1) % (trav->num * 2);
 436                         trav->hash[h].index = i+1;
 437                         trav->hash[h].key = op[i].key;
 438                 }
 439         } else
 440                 trav->hash = NULL;
 441 }
 442
 443 /* Keep -Wmissing-declarations happy: */
 444 const struct op_table *
 445 find_keyword (register const char *str, register unsigned int len);
 446
 447 #include "keywords.c"
 448
 449 struct depend {
 450         /* We can have more than one */
 451         struct list_node pre_list;
 452         struct list_node post_list;
 453         unsigned int needs_file;
 454         unsigned int needs_opnum;
 455         unsigned int satisfies_file;
 456         unsigned int satisfies_opnum;
 457 };
 458
 459 static void check_deps(const char *filename, struct op op[], unsigned int num)
 460 {
 461 #ifdef DEBUG_DEPS
 462         unsigned int i;
 463
 464         for (i = 1; i < num; i++)
 465                 if (!list_empty(&op[i].pre))
 466                         fail(filename, i+1, "Still has dependencies");
 467 #endif
 468 }
 469
 470 static void dump_pre(char *filename[], unsigned int file,
 471                      struct op op[], unsigned int i)
 472 {
 473         struct depend *dep;
 474
 475         printf("%s:%u still waiting for:\n", filename[file], i+1);
 476         list_for_each(&op[i].pre, dep, pre_list)
 477                 printf("    %s:%u\n",
 478                        filename[dep->satisfies_file], dep->satisfies_opnum+1);
 479         check_deps(filename[file], op, i);
 480 }
 481
 482 /* We simply read/write pointers, since we all are children. */
 483 static void do_pre(char *filename[], unsigned int file, int pre_fd,
 484                    struct op op[], unsigned int i)
 485 {
 486         while (!list_empty(&op[i].pre)) {
 487                 struct depend *dep;
 488
 489 #if DEBUG_DEPS
 490                 printf("%s:%u:waiting for pre\n", filename[file], i+1);
 491                 fflush(stdout);
 492 #endif
 493                 alarm(10);
 494                 while (read(pre_fd, &dep, sizeof(dep)) != sizeof(dep)) {
 495                         if (errno == EINTR) {
 496                                 dump_pre(filename, file, op, i);
 497                                 exit(1);
 498                         } else
 499                                 errx(1, "Reading from pipe");
 500                 }
 501                 alarm(0);
 502
 503 #if DEBUG_DEPS
 504                 printf("%s:%u:got pre %u from %s:%u\n", filename[file], i+1,
 505                        dep->needs_op, dep->satisfies_file, dep->satisfies_op+1);
 506                 fflush(stdout);
 507 #endif
 508                 /* This could be any op, not just this one. */
 509                 talloc_free(dep);
 510         }
 511 }
 512
 513 static void do_post(char *filename[], unsigned int file,
 514                     const struct op op[], unsigned int i)
 515 {
 516         struct depend *dep;
 517
 518         list_for_each(&op[i].post, dep, post_list) {
 519 #if DEBUG_DEPS
 520                 printf("%s:%u:sending to file %s:%u\n", filename[file], i+1,
 521                        filename[dep->needs_file], dep->needs_opnum+1);
 522 #endif
 523                 if (write(pipes[dep->needs_file].fd[1], &dep, sizeof(dep))
 524                     != sizeof(dep))
 525                         err(1, "%s:%u failed to tell file %s",
 526                             filename[file], i+1, filename[dep->needs_file]);
 527         }
 528 }
 529
 530 static int get_len(TDB_DATA key, TDB_DATA data, void *private_data)
 531 {
 532         return data.dsize;
 533 }
 534
 535 static unsigned run_ops(struct tdb_context *tdb,
 536                         int pre_fd,
 537                         char *filename[],
 538                         unsigned int file,
 539                         struct op op[],
 540                         unsigned int start, unsigned int stop);
 541
 542 struct traverse_info {
 543         struct op *op;
 544         char **filename;
 545         unsigned file;
 546         int pre_fd;
 547         unsigned int start;
 548         unsigned int i;
 549 };
 550
 551 /* Trivial case: do whatever they did for this key. */
 552 static int trivial_traverse(struct tdb_context *tdb,
 553                             TDB_DATA key, TDB_DATA data,
 554                             void *_tinfo)
 555 {
 556         struct traverse_info *tinfo = _tinfo;
 557         struct traverse *trav = tinfo->op[tinfo->start].trav;
 558         unsigned int h = hash_key(&key) % (trav->num * 2);
 559
 560         while (trav->hash[h].index) {
 561                 if (key_eq(trav->hash[h].key, key)) {
 562                         run_ops(tdb, tinfo->pre_fd, tinfo->filename,
 563                                 tinfo->file, tinfo->op, trav->hash[h].index,
 564                                 trav->end);
 565                         tinfo->i++;
 566                         return 0;
 567                 }
 568                 h = (h + 1) % (trav->num * 2);
 569         }
 570         fail(tinfo->filename[tinfo->file], tinfo->start + 1,
 571              "unexpected traverse key");
 572 }
 573
 574 /* More complex.  Just do whatever's they did at the n'th entry. */
 575 static int nontrivial_traverse(struct tdb_context *tdb,
 576                                TDB_DATA key, TDB_DATA data,
 577                                void *_tinfo)
 578 {
 579         struct traverse_info *tinfo = _tinfo;
 580         struct traverse *trav = tinfo->op[tinfo->start].trav;
 581
 582         if (tinfo->i == trav->end) {
 583                 /* This can happen if traverse expects to be empty. */
 584                 if (tinfo->start + 1 == trav->end)
 585                         return 1;
 586                 fail(tinfo->filename[tinfo->file], tinfo->start + 1,
 587                      "traverse did not terminate");
 588         }
 589
 590         if (tinfo->op[tinfo->i].op != OP_TDB_TRAVERSE)
 591                 fail(tinfo->filename[tinfo->file], tinfo->start + 1,
 592                      "%s:%u:traverse terminated early");
 593
 594         /* Run any normal ops. */
 595         tinfo->i = run_ops(tdb, tinfo->pre_fd, tinfo->filename, tinfo->file,
 596                            tinfo->op, tinfo->i+1, trav->end);
 597
 598         if (tinfo->i == trav->end)
 599                 return 1;
 600
 601         return 0;
 602 }
 603
 604 static unsigned op_traverse(struct tdb_context *tdb,
 605                             int pre_fd,
 606                             char *filename[],
 607                             unsigned int file,
 608                             int (*traversefn)(struct tdb_context *,
 609                                               tdb_traverse_func, void *),
 610                             struct op op[],
 611                             unsigned int start)
 612 {
 613         struct traverse *trav = op[start].trav;
 614         struct traverse_info tinfo = { op, filename, file, pre_fd,
 615                                        start, start+1 };
 616
 617         /* Trivial case. */
 618         if (trav->hash) {
 619                 int ret = traversefn(tdb, trivial_traverse, &tinfo);
 620                 if (ret != trav->num)
 621                         fail(filename[file], start+1,
 622                              "short traversal %i", ret);
 623                 return trav->end;
 624         }
 625
 626         traversefn(tdb, nontrivial_traverse, &tinfo);
 627
 628         /* Traversing in wrong order can have strange effects: eg. if
 629          * original traverse went A (delete A), B, we might do B
 630          * (delete A).  So if we have ops left over, we do it now. */
 631         while (tinfo.i != trav->end) {
 632                 if (op[tinfo.i].op == OP_TDB_TRAVERSE)
 633                         tinfo.i++;
 634                 else
 635                         tinfo.i = run_ops(tdb, pre_fd, filename, file, op,
 636                                           tinfo.i, trav->end);
 637         }
 638
 639         return trav->end;
 640 }
 641
 642 static void break_out(int sig)
 643 {
 644 }
 645
 646 static __attribute__((noinline))
 647 unsigned run_ops(struct tdb_context *tdb,
 648                  int pre_fd,
 649                  char *filename[],
 650                  unsigned int file,
 651                  struct op op[], unsigned int start, unsigned int stop)
 652 {
 653         unsigned int i;
 654         struct sigaction sa;
 655
 656         sa.sa_handler = break_out;
 657         sa.sa_flags = 0;
 658
 659         sigaction(SIGALRM, &sa, NULL);
 660         for (i = start; i < stop; i++) {
 661                 do_pre(filename, file, pre_fd, op, i);
 662
 663                 switch (op[i].op) {
 664                 case OP_TDB_LOCKALL:
 665                         try(tdb_lockall(tdb), op[i].ret);
 666                         break;
 667                 case OP_TDB_LOCKALL_MARK:
 668                         try(tdb_lockall_mark(tdb), op[i].ret);
 669                         break;
 670                 case OP_TDB_LOCKALL_UNMARK:
 671                         try(tdb_lockall_unmark(tdb), op[i].ret);
 672                         break;
 673                 case OP_TDB_LOCKALL_NONBLOCK:
 674                         unreliable(tdb_lockall_nonblock(tdb), op[i].ret,
 675                                    tdb_lockall(tdb), tdb_unlockall(tdb));
 676                         break;
 677                 case OP_TDB_UNLOCKALL:
 678                         try(tdb_unlockall(tdb), op[i].ret);
 679                         break;
 680                 case OP_TDB_LOCKALL_READ:
 681                         try(tdb_lockall_read(tdb), op[i].ret);
 682                         break;
 683                 case OP_TDB_LOCKALL_READ_NONBLOCK:
 684                         unreliable(tdb_lockall_read_nonblock(tdb), op[i].ret,
 685                                    tdb_lockall_read(tdb),
 686                                    tdb_unlockall_read(tdb));
 687                         break;
 688                 case OP_TDB_UNLOCKALL_READ:
 689                         try(tdb_unlockall_read(tdb), op[i].ret);
 690                         break;
 691                 case OP_TDB_CHAINLOCK:
 692                         try(tdb_chainlock(tdb, op[i].key), op[i].ret);
 693                         break;
 694                 case OP_TDB_CHAINLOCK_NONBLOCK:
 695                         unreliable(tdb_chainlock_nonblock(tdb, op[i].key),
 696                                    op[i].ret,
 697                                    tdb_chainlock(tdb, op[i].key),
 698                                    tdb_chainunlock(tdb, op[i].key));
 699                         break;
 700                 case OP_TDB_CHAINLOCK_MARK:
 701                         try(tdb_chainlock_mark(tdb, op[i].key), op[i].ret);
 702                         break;
 703                 case OP_TDB_CHAINLOCK_UNMARK:
 704                         try(tdb_chainlock_unmark(tdb, op[i].key), op[i].ret);
 705                         break;
 706                 case OP_TDB_CHAINUNLOCK:
 707                         try(tdb_chainunlock(tdb, op[i].key), op[i].ret);
 708                         break;
 709                 case OP_TDB_CHAINLOCK_READ:
 710                         try(tdb_chainlock_read(tdb, op[i].key), op[i].ret);
 711                         break;
 712                 case OP_TDB_CHAINUNLOCK_READ:
 713                         try(tdb_chainunlock_read(tdb, op[i].key), op[i].ret);
 714                         break;
 715                 case OP_TDB_PARSE_RECORD:
 716                         try(tdb_parse_record(tdb, op[i].key, get_len, NULL),
 717                             op[i].ret);
 718                         break;
 719                 case OP_TDB_EXISTS:
 720                         try(tdb_exists(tdb, op[i].key), op[i].ret);
 721                         break;
 722                 case OP_TDB_STORE:
 723                         try(tdb_store(tdb, op[i].key, op[i].data, op[i].flag),
 724                             op[i].ret);
 725                         break;
 726                 case OP_TDB_APPEND:
 727                         try(tdb_append(tdb, op[i].key, op[i].data), op[i].ret);
 728                         break;
 729                 case OP_TDB_GET_SEQNUM:
 730                         try(tdb_get_seqnum(tdb), op[i].ret);
 731                         break;
 732                 case OP_TDB_WIPE_ALL:
 733                         try(tdb_wipe_all(tdb), op[i].ret);
 734                         break;
 735                 case OP_TDB_TRANSACTION_START:
 736                         try(tdb_transaction_start(tdb), op[i].ret);
 737                         break;
 738                 case OP_TDB_TRANSACTION_CANCEL:
 739                         try(tdb_transaction_cancel(tdb), op[i].ret);
 740                         break;
 741                 case OP_TDB_TRANSACTION_COMMIT:
 742                         try(tdb_transaction_commit(tdb), op[i].ret);
 743                         break;
 744                 case OP_TDB_TRAVERSE_READ_START:
 745                         i = op_traverse(tdb, pre_fd, filename, file,
 746                                         tdb_traverse_read, op, i);
 747                         break;
 748                 case OP_TDB_TRAVERSE_START:
 749                         i = op_traverse(tdb, pre_fd, filename, file,
 750                                         tdb_traverse, op, i);
 751                         break;
 752                 case OP_TDB_TRAVERSE:
 753                         /* Terminate: we're in a traverse, and we've
 754                          * done our ops. */
 755                         return i;
 756                 case OP_TDB_TRAVERSE_END:
 757                         fail(filename[file], i+1, "unepxected end traverse");
 758                 /* FIXME: These must be treated like traverse. */
 759                 case OP_TDB_FIRSTKEY:
 760                         if (!key_eq(tdb_firstkey(tdb), op[i].data))
 761                                 fail(filename[file], i+1, "bad firstkey");
 762                         break;
 763                 case OP_TDB_NEXTKEY:
 764                         if (!key_eq(tdb_nextkey(tdb, op[i].key), op[i].data))
 765                                 fail(filename[file], i+1, "bad nextkey");
 766                         break;
 767                 case OP_TDB_FETCH: {
 768                         TDB_DATA f = tdb_fetch(tdb, op[i].key);
 769                         if (!key_eq(f, op[i].data))
 770                                 fail(filename[file], i+1, "bad fetch %u",
 771                                      f.dsize);
 772                         break;
 773                 }
 774                 case OP_TDB_DELETE:
 775                         try(tdb_delete(tdb, op[i].key), op[i].ret);
 776                         break;
 777                 }
 778                 do_post(filename, file, op, i);
 779         }
 780         return i;
 781 }
 782
 783 static struct op *load_tracefile(const char *filename, unsigned int *num,
 784                                  unsigned int *hashsize,
 785                                  unsigned int *tdb_flags,
 786                                  unsigned int *open_flags)
 787 {
 788         unsigned int i;
 789         struct op *op = talloc_array(NULL, struct op, 1);
 790         char **words;
 791         char **lines;
 792         char *file;
 793
 794         file = grab_file(NULL, filename, NULL);
 795         if (!file)
 796                 err(1, "Reading %s", filename);
 797
 798         lines = strsplit(file, file, "\n", NULL);
 799         if (!lines[0])
 800                 errx(1, "%s is empty", filename);
 801
 802         words = strsplit(lines, lines[0], " ", NULL);
 803         if (!streq(words[1], "tdb_open"))
 804                 fail(filename, 1, "does not start with tdb_open");
 805
 806         *hashsize = atoi(words[2]);
 807         *tdb_flags = strtoul(words[3], NULL, 0);
 808         *open_flags = strtoul(words[4], NULL, 0);
 809
 810         for (i = 1; lines[i]; i++) {
 811                 const struct op_table *opt;
 812
 813                 words = strsplit(lines, lines[i], " ", NULL);
 814                 if (!words[0] || !words[1])
 815                         fail(filename, i+1, "Expected serial number and op");
 816
 817                 opt = find_keyword(words[1], strlen(words[1]));
 818                 if (!opt) {
 819                         if (streq(words[1], "tdb_close")) {
 820                                 if (lines[i+1])
 821                                         fail(filename, i+2,
 822                                              "lines after tdb_close");
 823                                 *num = i;
 824                                 talloc_free(lines);
 825                                 return op;
 826                         }
 827                         fail(filename, i+1, "Unknown operation '%s'", words[1]);
 828                 }
 829
 830                 add_op(filename, &op, i, atoi(words[0]), opt->type);
 831                 opt->enhance_op(filename, op, i, words);
 832         }
 833
 834         fprintf(stderr, "%s:%u:last operation is not tdb_close: incomplete?",
 835               filename, i);
 836         talloc_free(lines);
 837         *num = i - 1;
 838         return op;
 839 }
 840
 841 /* We remember all the keys we've ever seen, and who has them. */
 842 struct key_user {
 843         unsigned int file;
 844         unsigned int op_num;
 845 };
 846
 847 struct keyinfo {
 848         TDB_DATA key;
 849         unsigned int num_users;
 850         struct key_user *user;
 851 };
 852
 853 static const TDB_DATA must_not_exist;
 854 static const TDB_DATA must_exist;
 855 static const TDB_DATA not_exists_or_empty;
 856
 857 /* NULL means doesn't care if it exists or not, &must_exist means
 858  * it must exist but we don't care what, &must_not_exist means it must
 859  * not exist, otherwise the data it needs. */
 860 static const TDB_DATA *needs(const struct op *op)
 861 {
 862         switch (op->op) {
 863         /* FIXME: Pull forward deps, since we can deadlock */
 864         case OP_TDB_CHAINLOCK:
 865         case OP_TDB_CHAINLOCK_NONBLOCK:
 866         case OP_TDB_CHAINLOCK_MARK:
 867         case OP_TDB_CHAINLOCK_UNMARK:
 868         case OP_TDB_CHAINUNLOCK:
 869         case OP_TDB_CHAINLOCK_READ:
 870         case OP_TDB_CHAINUNLOCK_READ:
 871                 return NULL;
 872
 873         case OP_TDB_APPEND:
 874                 if (op->append.pre.dsize == 0)
 875                         return &not_exists_or_empty;
 876                 return &op->append.pre;
 877
 878         case OP_TDB_STORE:
 879                 if (op->flag == TDB_INSERT) {
 880                         if (op->ret < 0)
 881                                 return &must_exist;
 882                         else
 883                                 return &must_not_exist;
 884                 } else if (op->flag == TDB_MODIFY) {
 885                         if (op->ret < 0)
 886                                 return &must_not_exist;
 887                         else
 888                                 return &must_exist;
 889                 }
 890                 /* No flags?  Don't care */
 891                 return NULL;
 892
 893         case OP_TDB_EXISTS:
 894                 if (op->ret == 1)
 895                         return &must_exist;
 896                 else
 897                         return &must_not_exist;
 898
 899         case OP_TDB_PARSE_RECORD:
 900                 if (op->ret < 0)
 901                         return &must_not_exist;
 902                 return &must_exist;
 903
 904         /* FIXME: handle these. */
 905         case OP_TDB_WIPE_ALL:
 906         case OP_TDB_FIRSTKEY:
 907         case OP_TDB_NEXTKEY:
 908         case OP_TDB_GET_SEQNUM:
 909         case OP_TDB_TRAVERSE:
 910         case OP_TDB_TRANSACTION_COMMIT:
 911         case OP_TDB_TRANSACTION_CANCEL:
 912         case OP_TDB_TRANSACTION_START:
 913                 return NULL;
 914
 915         case OP_TDB_FETCH:
 916                 if (!op->data.dptr)
 917                         return &must_not_exist;
 918                 return &op->data;
 919
 920         case OP_TDB_DELETE:
 921                 if (op->ret < 0)
 922                         return &must_not_exist;
 923                 return &must_exist;
 924
 925         default:
 926                 errx(1, "Unexpected op %i", op->op);
 927         }
 928
 929 }
 930
 931 /* What's the data after this op?  pre if nothing changed. */
 932 static const TDB_DATA *gives(const struct op *op, const TDB_DATA *pre)
 933 {
 934         /* Failed ops don't change state of db. */
 935         if (op->ret < 0)
 936                 return pre;
 937
 938         if (op->op == OP_TDB_DELETE || op->op == OP_TDB_WIPE_ALL)
 939                 return &tdb_null;
 940
 941         if (op->op == OP_TDB_APPEND)
 942                 return &op->append.post;
 943
 944         if (op->op == OP_TDB_STORE)
 945                 return &op->data;
 946
 947         return pre;
 948 }
 949
 950 static struct keyinfo *hash_ops(struct op *op[], unsigned int num_ops[],
 951                                 unsigned int num)
 952 {
 953         unsigned int i, j, h;
 954         struct keyinfo *hash;
 955
 956         hash = talloc_zero_array(op[0], struct keyinfo, total_keys*2);
 957         for (i = 0; i < num; i++) {
 958                 for (j = 1; j < num_ops[i]; j++) {
 959                         /* We can't do this on allocation, due to realloc. */
 960                         list_head_init(&op[i][j].post);
 961                         list_head_init(&op[i][j].pre);
 962
 963                         if (!op[i][j].key.dptr)
 964                                 continue;
 965
 966                         /* We don't wait for traverse keys */
 967                         /* FIXME: We should, for trivial traversals. */
 968                         if (op[i][j].op == OP_TDB_TRAVERSE)
 969                                 continue;
 970
 971                         h = hash_key(&op[i][j].key) % (total_keys * 2);
 972                         while (!key_eq(hash[h].key, op[i][j].key)) {
 973                                 if (!hash[h].key.dptr) {
 974                                         hash[h].key = op[i][j].key;
 975                                         break;
 976                                 }
 977                                 h = (h + 1) % (total_keys * 2);
 978                         }
 979                         /* Might as well save some memory if we can. */
 980                         if (op[i][j].key.dptr != hash[h].key.dptr) {
 981                                 talloc_free(op[i][j].key.dptr);
 982                                 op[i][j].key.dptr = hash[h].key.dptr;
 983                         }
 984                         hash[h].user = talloc_realloc(hash, hash[h].user,
 985                                                      struct key_user,
 986                                                      hash[h].num_users+1);
 987                         hash[h].user[hash[h].num_users].op_num = j;
 988                         hash[h].user[hash[h].num_users].file = i;
 989                         hash[h].num_users++;
 990                 }
 991         }
 992
 993         return hash;
 994 }
 995
 996 static bool satisfies(const TDB_DATA *data, const TDB_DATA *need)
 997 {
 998         /* Don't need anything?  Cool. */
 999         if (!need)
1000                 return true;
1001
1002         /* This should be tdb_null or a real value. */
1003         assert(data != &must_exist);
1004         assert(data != &must_not_exist);
1005         assert(data != &not_exists_or_empty);
1006
1007         /* must_not_exist == must_not_exist, must_exist == must_exist, or
1008            not_exists_or_empty == not_exists_or_empty. */
1009         if (data->dsize == need->dsize && data->dptr == need->dptr)
1010                 return true;
1011
1012         /* Must not exist?  data must not exist. */
1013         if (need == &must_not_exist)
1014                 return data->dptr == NULL;
1015
1016         /* Must exist? */
1017         if (need == &must_exist)
1018                 return data->dptr != NULL;
1019
1020         /* Either noexist or empty. */
1021         if (need == &not_exists_or_empty)
1022                 return data->dsize == 0;
1023
1024         /* Needs something specific. */
1025         return key_eq(*data, *need);
1026 }
1027
1028 static bool sort_deps(char *filename[], struct op *op[],
1029                       struct key_user res[], unsigned num,
1030                       const TDB_DATA *data)
1031 {
1032         unsigned int i;
1033
1034         /* Nothing left?  We're sorted. */
1035         if (num == 0)
1036                 return true;
1037
1038         for (i = 0; i < num; i++) {
1039                 struct op *this_op = &op[res[i].file][res[i].op_num];
1040
1041                 /* Is what we have good enough for this op? */
1042                 if (satisfies(data, needs(this_op))) {
1043                         /* Try this one next. */
1044                         struct key_user tmp = res[0];
1045                         res[0] = res[i];
1046                         res[i] = tmp;
1047                         if (sort_deps(filename, op, res+1, num-1,
1048                                       gives(this_op, data)))
1049                                 return true;
1050                 }
1051         }
1052         /* No combination worked. */
1053         return false;
1054 }
1055
1056 /* All these ops have the same serial number.  Which comes first?
1057  *
1058  * This can happen both because read ops or failed write ops don't
1059  * change serial number, and also due to race since we access the
1060  * number unlocked (the race can cause less detectable ordering problems,
1061  * in which case we'll deadlock and report: fix manually in that case).
1062  */
1063 static void figure_deps(char *filename[], struct op *op[],
1064                         struct key_user user[], unsigned start, unsigned end)
1065 {
1066         unsigned int i;
1067         /* We assume database starts empty. */
1068         const struct TDB_DATA *data = &tdb_null;
1069
1070         /* What do we have to start with? */
1071         for (i = 0; i < start; i++)
1072                 data = gives(&op[user[i].file][user[i].op_num], data);
1073
1074         if (!sort_deps(filename, op, user + start, end - start, data))
1075                 fail(filename[user[start].file], user[start].op_num+1,
1076                      "Could not resolve inter-dependencies");
1077 }
1078
1079 static void sort_ops(struct keyinfo hash[], char *filename[], struct op *op[])
1080 {
1081         unsigned int h;
1082
1083         /* Gcc nexted function extension.  How cool is this? */
1084         int compare_serial(const void *_a, const void *_b)
1085         {
1086                 const struct key_user *a = _a, *b = _b;
1087                 return op[a->file][a->op_num].serial
1088                         - op[b->file][b->op_num].serial;
1089         }
1090
1091         /* Now sort into seqnum order. */
1092         for (h = 0; h < total_keys * 2; h++) {
1093                 unsigned int i, same;
1094                 struct key_user *user = hash[h].user;
1095
1096                 qsort(user, hash[h].num_users, sizeof(user[0]), compare_serial);
1097
1098                 /* Try to deal with same serial numbers. */
1099                 for (i = 1, same = 0; i < hash[h].num_users; i++) {
1100                         if (op[user[i].file][user[i].op_num].serial
1101                             == op[user[i-1].file][user[i-1].op_num].serial) {
1102                                 same++;
1103                                 continue;
1104                         }
1105
1106                         if (same) {
1107                                 figure_deps(filename, op, user, i-same-1, i);
1108                                 same = 0;
1109                         }
1110                 }
1111                 if (same)
1112                         figure_deps(filename, op, user, i-same-1, i);
1113         }
1114 }
1115
1116 static int destroy_depend(struct depend *dep)
1117 {
1118         list_del(&dep->pre_list);
1119         list_del(&dep->post_list);
1120         return 0;
1121 }
1122
1123 static unsigned int dep_count;
1124 static void add_dependency(void *ctx,
1125                            struct op *op[],
1126                            char *filename[],
1127                            unsigned int needs_file,
1128                            unsigned int needs_opnum,
1129                            unsigned int satisfies_file,
1130                            unsigned int satisfies_opnum)
1131 {
1132         struct depend *dep;
1133         unsigned int needs_start, sat_start;
1134
1135         /* We don't depend on ourselves. */
1136         if (needs_file == satisfies_file)
1137                 return;
1138
1139 #if DEBUG_DEPS
1140         printf("%s:%u: depends on %s:%u\n",
1141                filename[needs_file], needs_opnum+1,
1142                filename[satisfies_file], satisfies_opnum+1);
1143 #endif
1144
1145         needs_start = op[needs_file][needs_opnum].group_start;
1146         sat_start = op[satisfies_file][satisfies_opnum].group_start;
1147
1148         /* If needs is in a transaction, we need it before start. */
1149         if (needs_start) {
1150                 switch (op[needs_file][needs_start].op) {
1151                 case OP_TDB_TRANSACTION_START:
1152                         needs_opnum = needs_start;
1153 #ifdef DEBUG_DEPS
1154                         printf("  -> Back to %u\n", needs_start+1);
1155                         fflush(stdout);
1156 #endif
1157                         break;
1158                 default:
1159                         break;
1160                 }
1161         }
1162
1163         /* If satisfies is in a transaction, we wait until after commit. */
1164         /* FIXME: If transaction is cancelled, don't need dependency. */
1165         if (sat_start) {
1166                 if (op[satisfies_file][sat_start].op
1167                     == OP_TDB_TRANSACTION_START) {
1168                         satisfies_opnum
1169                                 = op[satisfies_file][sat_start].transaction_end;
1170 #ifdef DEBUG_DEPS
1171                         printf("  -> Depends on %u\n", satisfies_opnum+1);
1172                         fflush(stdout);
1173 #endif
1174                 }
1175         }
1176
1177         dep = talloc(ctx, struct depend);
1178         dep->needs_file = needs_file;
1179         dep->needs_opnum = needs_opnum;
1180         dep->satisfies_file = satisfies_file;
1181         dep->satisfies_opnum = satisfies_opnum;
1182         list_add(&op[satisfies_file][satisfies_opnum].post, &dep->post_list);
1183         list_add(&op[needs_file][needs_opnum].pre, &dep->pre_list);
1184         talloc_set_destructor(dep, destroy_depend);
1185
1186         dep_count++;
1187 }
1188
1189 #if TRAVERSALS_TAKE_TRANSACTION_LOCK
1190 struct traverse_dep {
1191         unsigned int file;
1192         unsigned int op_num;
1193         const struct op *op;
1194 };
1195
1196 /* Sort by which one runs first. */
1197 static int compare_traverse_dep(const void *_a, const void *_b)
1198 {
1199         const struct traverse_dep *a = _a, *b = _b;
1200         const struct traverse *trava = a->op->trav, *travb = b->op->trav;
1201
1202         if (a->op->serial != b->op->serial)
1203                 return a->op->serial - b->op->serial;
1204
1205         /* If they have same serial, it means one didn't make any changes.
1206          * Thus sort by end in that case. */
1207         return a->op[trava->end - a->op_num].serial
1208                 - b->op[travb->end - b->op_num].serial;
1209 }
1210
1211 /* Traversals can deadlock against each other.  Force order. */
1212 static void make_traverse_depends(char *filename[],
1213                                   struct op *op[], unsigned int num_ops[],
1214                                   unsigned int num)
1215 {
1216         unsigned int i, j, num_traversals = 0;
1217         struct traverse_dep *dep;
1218
1219         dep = talloc_array(NULL, struct traverse_dep, 1);
1220
1221         /* Count them. */
1222         for (i = 0; i < num; i++) {
1223                 for (j = 0; j < num_ops[i]; j++) {
1224                         if (op[i][j].op == OP_TDB_TRAVERSE_START
1225                             || op[i][j].op == OP_TDB_TRAVERSE_READ_START) {
1226                                 dep = talloc_realloc(NULL, dep,
1227                                                      struct traverse_dep,
1228                                                      num_traversals+1);
1229                                 dep[num_traversals].file = i;
1230                                 dep[num_traversals].op_num = j;
1231                                 dep[num_traversals].op = &op[i][j];
1232                                 num_traversals++;
1233                         }
1234                 }
1235         }
1236         qsort(dep, num_traversals, sizeof(dep[0]), compare_traverse_dep);
1237         for (i = 1; i < num_traversals; i++) {
1238                 /* i depends on end of traverse i-1. */
1239                 add_dependency(NULL, op, filename, dep[i].file, dep[i].op_num,
1240                                dep[i-1].file, dep[i-1].op->trav->end);
1241         }
1242         talloc_free(dep);
1243         printf("Dep count after traverses: %u\n", dep_count);
1244 }
1245 #endif /* TRAVERSALS_TAKE_TRANSACTION_LOCK */
1246
1247 static bool changes_db(const struct op *op)
1248 {
1249         return gives(op, NULL) != NULL;
1250 }
1251
1252 static void depend_on_previous(struct op *op[],
1253                                char *filename[],
1254                                unsigned int num,
1255                                struct key_user user[],
1256                                unsigned int i,
1257                                int prev)
1258 {
1259         bool deps[num];
1260         int j;
1261
1262         if (i == 0)
1263                 return;
1264
1265         if (prev == i - 1) {
1266                 /* Just depend on previous. */
1267                 add_dependency(NULL, op, filename,
1268                                user[i].file, user[i].op_num,
1269                                user[prev].file, user[prev].op_num);
1270                 return;
1271         }
1272
1273         /* We have to wait for the readers.  Find last one in *each* file. */
1274         memset(deps, 0, sizeof(deps));
1275         deps[user[i].file] = true;
1276         for (j = i - 1; j > prev; j--) {
1277                 if (!deps[user[j].file]) {
1278                         add_dependency(NULL, op, filename,
1279                                        user[i].file, user[i].op_num,
1280                                        user[j].file, user[j].op_num);
1281                         deps[user[j].file] = true;
1282                 }
1283         }
1284 }
1285
1286 static void derive_dependencies(char *filename[],
1287                                 struct op *op[], unsigned int num_ops[],
1288                                 unsigned int num)
1289 {
1290         struct keyinfo *hash;
1291         unsigned int h, i;
1292
1293         /* Create hash table for faster key lookup. */
1294         hash = hash_ops(op, num_ops, num);
1295
1296         /* Now handle the hard cases: same serial number. */
1297         sort_ops(hash, filename, op);
1298
1299         /* Create dependencies back to the last change, rather than
1300          * creating false dependencies by naively making each one
1301          * depend on the previous.  This has two purposes: it makes
1302          * later optimization simpler, and it also avoids deadlock with
1303          * same sequence number ops inside traversals (if one
1304          * traversal doesn't write anything, two ops can have the same
1305          * sequence number yet we can create a traversal dependency
1306          * the other way). */
1307         for (h = 0; h < total_keys * 2; h++) {
1308                 int prev = -1;
1309
1310                 if (hash[h].num_users < 2)
1311                         continue;
1312
1313                 for (i = 0; i < hash[h].num_users; i++) {
1314                         if (changes_db(&op[hash[h].user[i].file]
1315                                        [hash[h].user[i].op_num])) {
1316                                 depend_on_previous(op, filename, num,
1317                                                    hash[h].user, i, prev);
1318                                 prev = i;
1319                         } else if (prev >= 0)
1320                                 add_dependency(hash, op, filename,
1321                                                hash[h].user[i].file,
1322                                                hash[h].user[i].op_num,
1323                                                hash[h].user[prev].file,
1324                                                hash[h].user[prev].op_num);
1325                 }
1326         }
1327         printf("Dep count after deriving: %u\n", dep_count);
1328
1329 #if TRAVERSALS_TAKE_TRANSACTION_LOCK
1330         make_traverse_depends(filename, op, num_ops, num);
1331 #endif
1332 }
1333
1334 int main(int argc, char *argv[])
1335 {
1336         struct timeval start, end;
1337         unsigned int i, num_ops[argc], hashsize[argc], tdb_flags[argc], open_flags[argc];
1338         struct op *op[argc];
1339         int fds[2];
1340         char c;
1341         bool ok = true;
1342
1343         if (argc < 3)
1344                 errx(1, "Usage: %s <tdbfile> <tracefile>...", argv[0]);
1345
1346         pipes = talloc_array(NULL, struct pipe, argc - 2);
1347         for (i = 0; i < argc - 2; i++) {
1348                 printf("Loading tracefile %s...", argv[2+i]);
1349                 fflush(stdout);
1350                 op[i] = load_tracefile(argv[2+i], &num_ops[i], &hashsize[i],
1351                                        &tdb_flags[i], &open_flags[i]);
1352                 if (pipe(pipes[i].fd) != 0)
1353                         err(1, "creating pipe");
1354                 printf("done\n");
1355         }
1356
1357         printf("Calculating inter-dependencies...");
1358         fflush(stdout);
1359         derive_dependencies(argv+2, op, num_ops, i);
1360         printf("done\n");
1361
1362         /* Don't fork for single arg case: simple debugging. */
1363         if (argc == 3) {
1364                 struct tdb_context *tdb;
1365                 tdb = tdb_open_ex(argv[1], hashsize[0], tdb_flags[0],
1366                                   open_flags[0], 0600,
1367                                   NULL, hash_key);
1368                 printf("Single threaded run...");
1369                 fflush(stdout);
1370
1371                 run_ops(tdb, pipes[0].fd[0], argv+2, 0, op[0], 1, num_ops[0]);
1372                 check_deps(argv[2], op[0], num_ops[0]);
1373
1374                 printf("done\n");
1375                 exit(0);
1376         }
1377
1378         if (pipe(fds) != 0)
1379                 err(1, "creating pipe");
1380
1381         for (i = 0; i < argc - 2; i++) {
1382                 struct tdb_context *tdb;
1383
1384                 switch (fork()) {
1385                 case -1:
1386                         err(1, "fork failed");
1387                 case 0:
1388                         close(fds[1]);
1389                         tdb = tdb_open_ex(argv[1], hashsize[i], tdb_flags[i],
1390                                           open_flags[i], 0600,
1391                                           NULL, hash_key);
1392                         if (!tdb)
1393                                 err(1, "Opening tdb %s", argv[1]);
1394
1395                         /* This catches parent exiting. */
1396                         if (read(fds[0], &c, 1) != 1)
1397                                 exit(1);
1398                         run_ops(tdb, pipes[i].fd[0], argv+2, i, op[i], 1,
1399                                 num_ops[i]);
1400                         check_deps(argv[2+i], op[i], num_ops[i]);
1401                         exit(0);
1402                 default:
1403                         break;
1404                 }
1405         }
1406
1407         /* Let everything settle. */
1408         sleep(1);
1409
1410         printf("Starting run...");
1411         fflush(stdout);
1412         gettimeofday(&start, NULL);
1413         /* Tell them all to go!  Any write of sufficient length will do. */
1414         if (write(fds[1], hashsize, i) != i)
1415                 err(1, "Writing to wakeup pipe");
1416
1417         for (i = 0; i < argc - 2; i++) {
1418                 int status;
1419                 wait(&status);
1420                 if (!WIFEXITED(status)) {
1421                         warnx("Child died with signal %i", WTERMSIG(status));
1422                         ok = false;
1423                 } else if (WEXITSTATUS(status) != 0)
1424                         /* Assume child spat out error. */
1425                         ok = false;
1426         }
1427         if (!ok)
1428                 exit(1);
1429
1430         gettimeofday(&end, NULL);
1431         printf("done\n");
1432
1433         end.tv_sec -= start.tv_sec;
1434         printf("Time replaying: %lu usec\n",
1435                end.tv_sec * 1000000UL + (end.tv_usec - start.tv_usec));
1436
1437         exit(0);
1438 }