usr.bin/undo/undo.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/usr.bin/undo/undo.c,v 1.6 2008/07/17 21:34:47 thomas Exp $
  35  */
  36 /*
  37  * UNDO - retrieve an older version of a file.
  38  */
  39
  40 #include <sys/types.h>
  41 #include <sys/stat.h>
  42 #include <sys/wait.h>
  43 #include <sys/tree.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <stdarg.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49 #include <fcntl.h>
  50 #include <errno.h>
  51 #include <vfs/hammer/hammer_disk.h>
  52 #include <vfs/hammer/hammer_ioctl.h>
  53
  54 /*
  55  * Sorted list of transaction ids
  56  */
  57 struct undo_hist_entry;
  58 RB_HEAD(undo_hist_entry_rb_tree, undo_hist_entry);
  59 RB_PROTOTYPE2(undo_hist_entry_rb_tree, undo_hist_entry, rbnode,
  60         undo_hist_entry_compare, hammer_tid_t);
  61
  62 struct undo_hist_entry {
  63         RB_ENTRY(undo_hist_entry) rbnode;
  64         struct hammer_ioc_hist_entry tse;
  65         ino_t inum;
  66 };
  67
  68 enum undo_type { TYPE_FILE, TYPE_DIFF, TYPE_RDIFF, TYPE_HISTORY };
  69 enum undo_cmd { CMD_DUMP, CMD_ITERATEALL };
  70
  71 #define UNDO_FLAG_MULT          0x0001
  72 #define UNDO_FLAG_INOCHG        0x0002
  73 #define UNDO_FLAG_SETTID1       0x0004
  74 #define UNDO_FLAG_SETTID2       0x0008
  75
  76 static int undo_hist_entry_compare(struct undo_hist_entry *he1,
  77                     struct undo_hist_entry *he2);
  78 static void doiterate(const char *filename, const char *outFileName,
  79                    const char *outFilePostfix, int flags,
  80                    struct hammer_ioc_hist_entry ts1,
  81                    struct hammer_ioc_hist_entry ts2,
  82                    enum undo_cmd cmd, enum undo_type type);
  83 static void dogenerate(const char *filename, const char *outFileName,
  84                    const char *outFilePostfix,
  85                    int flags, int idx, enum undo_type type,
  86                    struct hammer_ioc_hist_entry ts1,
  87                    struct hammer_ioc_hist_entry ts2);
  88 static void collect_history(int fd, int *error,
  89                    struct undo_hist_entry_rb_tree *tse_tree);
  90 static void collect_dir_history(const char *filename, int *error,
  91                    struct undo_hist_entry_rb_tree *dir_tree);
  92 static void clean_tree(struct undo_hist_entry_rb_tree *tree);
  93 static hammer_tid_t parse_delta_time(const char *timeStr, int *flags,
  94                    int ind_flag);
  95 static void runcmd(int fd, const char *cmd, ...);
  96 static char *timestamp(hammer_ioc_hist_entry_t hen);
  97 static void usage(void);
  98
  99 static int VerboseOpt;
 100
 101 RB_GENERATE2(undo_hist_entry_rb_tree, undo_hist_entry, rbnode,
 102         undo_hist_entry_compare, hammer_tid_t, tse.tid);
 103
 104
 105 int
 106 main(int ac, char **av)
 107 {
 108         const char *outFileName = NULL;
 109         const char *outFilePostfix = NULL;
 110         enum undo_cmd cmd;
 111         enum undo_type type;
 112         struct hammer_ioc_hist_entry ts1;
 113         struct hammer_ioc_hist_entry ts2;
 114         int c;
 115         int count_t;
 116         int flags;
 117
 118         bzero(&ts1, sizeof(ts1));
 119         bzero(&ts2, sizeof(ts2));
 120
 121         cmd = CMD_DUMP;
 122         type = TYPE_FILE;
 123         count_t = 0;
 124         flags = 0;
 125
 126         while ((c = getopt(ac, av, "adDiuvo:t:")) != -1) {
 127                 switch(c) {
 128                 case 'd':
 129                         type = TYPE_DIFF;
 130                         break;
 131                 case 'D':
 132                         type = TYPE_RDIFF;
 133                         break;
 134                 case 'i':
 135                         if (type != TYPE_FILE)
 136                                 usage();
 137                         type = TYPE_HISTORY;
 138                         cmd = CMD_ITERATEALL;
 139                         break;
 140                 case 'a':
 141                         cmd = CMD_ITERATEALL;
 142                         break;
 143                 case 'u':
 144                         outFilePostfix = ".undo";
 145                         break;
 146                 case 'v':
 147                         ++VerboseOpt;
 148                         break;
 149                 case 'o':
 150                         outFileName = optarg;
 151                         break;
 152                 case 't':
 153                         /*
 154                          * Parse one or two -t options.  If two are specified
 155                          * -d is implied (but may be overridden)
 156                          */
 157                         ++count_t;
 158                         if (count_t == 1) {
 159                                 ts1.tid = parse_delta_time(optarg, &flags,
 160                                                            UNDO_FLAG_SETTID1);
 161                         } else if (count_t == 2) {
 162                                 ts2.tid = parse_delta_time(optarg, &flags,
 163                                                            UNDO_FLAG_SETTID2);
 164                                 if (type == TYPE_FILE)
 165                                         type = TYPE_DIFF;
 166                         } else {
 167                                 usage();
 168                         }
 169                         break;
 170                 default:
 171                         usage();
 172                         /* NOT REACHED */
 173                         break;
 174                 }
 175         }
 176
 177         /*
 178          * Option validation
 179          */
 180         if (outFileName && outFilePostfix) {
 181                 fprintf(stderr, "The -o option may not be combined with -u\n");
 182                 usage();
 183         }
 184
 185         ac -= optind;
 186         av += optind;
 187         if (ac > 1)
 188                 flags |= UNDO_FLAG_MULT;
 189
 190         if (ac == 0)
 191                 usage();
 192
 193         /*
 194          * Validate the output template, if specified.
 195          */
 196         if (outFileName && (flags & UNDO_FLAG_MULT)) {
 197                 const char *ptr = outFileName;
 198                 int didStr = 0;
 199
 200                 while ((ptr = strchr(ptr, '%')) != NULL) {
 201                         if (ptr[1] == 's') {
 202                                 if (didStr) {
 203                                         fprintf(stderr, "Malformed output "
 204                                                         "template\n");
 205                                         usage();
 206                                 }
 207                                 didStr = 1;
 208                                 ++ptr;
 209                         } else if (ptr[1] != '%') {
 210                                 fprintf(stderr, "Malformed output template\n");
 211                                 usage();
 212                         } else {
 213                                 ptr += 2;
 214                         }
 215                 }
 216         }
 217
 218         while (ac) {
 219                 doiterate(*av, outFileName, outFilePostfix,
 220                           flags, ts1, ts2, cmd, type);
 221                 ++av;
 222                 --ac;
 223         }
 224         return(0);
 225 }
 226
 227 /*
 228  * Iterate through a file's history.  If cmd == CMD_DUMP we take the
 229  * next-to-last transaction id, unless another given.  Otherwise if
 230  * cmd == CMD_ITERATEALL we scan all transaction ids.
 231  *
 232  * Also iterate through the directory's history to locate other inodes that
 233  * used the particular file name.
 234  */
 235 static
 236 void
 237 doiterate(const char *filename, const char *outFileName,
 238           const char *outFilePostfix, int flags,
 239           struct hammer_ioc_hist_entry ts1,
 240           struct hammer_ioc_hist_entry ts2,
 241           enum undo_cmd cmd, enum undo_type type)
 242 {
 243         struct undo_hist_entry_rb_tree dir_tree;
 244         struct undo_hist_entry_rb_tree tse_tree;
 245         struct undo_hist_entry *tse1;
 246         struct undo_hist_entry *tse2;
 247         struct hammer_ioc_hist_entry tid_max;
 248         struct stat sb;
 249         char *path = NULL;
 250         int i;
 251         int fd;
 252         int error;
 253
 254         RB_INIT(&dir_tree);
 255         RB_INIT(&tse_tree);
 256
 257         tid_max.tid = HAMMER_MAX_TID;
 258         tid_max.time32 = 0;
 259
 260         /*
 261          * Use the directory history to locate all possible versions of
 262          * the file.
 263          */
 264         collect_dir_history(filename, &error, &dir_tree);
 265         RB_FOREACH(tse1, undo_hist_entry_rb_tree, &dir_tree) {
 266                 asprintf(&path, "%s@@0x%016jx", filename, (uintmax_t)tse1->tse.tid);
 267                 if (stat(path, &sb) == 0 && sb.st_mode & S_IFIFO) {
 268                         fprintf(stderr, "Warning: fake transaction id 0x%016jx\n", (uintmax_t)tse1->tse.tid);
 269                         continue;
 270                 }
 271                 if ((fd = open(path, O_RDONLY)) > 0) {
 272                         collect_history(fd, &error, &tse_tree);
 273                         close(fd);
 274                 }
 275                 free(path);
 276         }
 277         if ((fd = open(filename, O_RDONLY)) > 0) {
 278                 collect_history(fd, &error, &tse_tree);
 279                 close(fd);
 280         }
 281         if (cmd == CMD_DUMP) {
 282                 if ((ts1.tid == 0 ||
 283                      flags & (UNDO_FLAG_SETTID1|UNDO_FLAG_SETTID2)) &&
 284                     RB_EMPTY(&tse_tree)) {
 285                         if ((fd = open(filename, O_RDONLY)) > 0) {
 286                                 collect_history(fd, &error, &tse_tree);
 287                                 close(fd);
 288                         }
 289                 }
 290                 /*
 291                  * Find entry if tid set to placeholder index
 292                  */
 293                 if (flags & UNDO_FLAG_SETTID1){
 294                         tse1 = RB_MAX(undo_hist_entry_rb_tree, &tse_tree);
 295                         while (tse1 && ts1.tid--) {
 296                                 tse1 = RB_PREV(undo_hist_entry_rb_tree,
 297                                                &tse_tree, tse1);
 298                         }
 299                         if (tse1)
 300                                 ts1 = tse1->tse;
 301                         else
 302                                 ts1.tid = 0;
 303                 }
 304                 if (flags & UNDO_FLAG_SETTID2){
 305                         tse2 = RB_MAX(undo_hist_entry_rb_tree, &tse_tree);
 306                         while (tse2 && ts2.tid--) {
 307                                 tse2 = RB_PREV(undo_hist_entry_rb_tree,
 308                                                &tse_tree, tse2);
 309                         }
 310                         if (tse2)
 311                                 ts2 = tse2->tse;
 312                         else
 313                                 ts2.tid = 0;
 314                 }
 315
 316                 /*
 317                  * Single entry, most recent prior to current
 318                  */
 319                 if (ts1.tid == 0) {
 320                         tse2 = RB_MAX(undo_hist_entry_rb_tree, &tse_tree);
 321                         if (tse2) {
 322                                 ts2 = tse2->tse;
 323                                 tse1 = RB_PREV(undo_hist_entry_rb_tree,
 324                                                &tse_tree, tse2);
 325                                 if (tse1)
 326                                         ts1 = tse1->tse;
 327                         }
 328                 }
 329                 if (ts1.tid == 0) {
 330                         printf("%s: No UNDO history found\n", filename);
 331                 } else {
 332                         dogenerate(filename,
 333                                    outFileName, outFilePostfix,
 334                                    0, 0, type,
 335                                    ts1, ts2);
 336                 }
 337         } else if (RB_ROOT(&tse_tree)) {
 338                 /*
 339                  * Iterate entire history
 340                  */
 341                 printf("%s: ITERATE ENTIRE HISTORY\n", filename);
 342
 343                 tse1 = NULL;
 344                 i = 0;
 345                 RB_FOREACH(tse2, undo_hist_entry_rb_tree, &tse_tree) {
 346                         if (tse1) {
 347                                 dogenerate(filename,
 348                                            outFileName, outFilePostfix,
 349                                            flags, i, type,
 350                                            tse1->tse, tse2->tse);
 351                         }
 352                         if (tse1 && tse2->inum != tse1->inum)
 353                                 flags |= UNDO_FLAG_INOCHG;
 354                         else
 355                                 flags &= ~UNDO_FLAG_INOCHG;
 356                         tse1 = tse2;
 357                         ++i;
 358                 }
 359                 /*
 360                  * There is no delta to print for the last pair,
 361                  * because they are identical.
 362                  */
 363                 if (type != TYPE_DIFF && type != TYPE_RDIFF) {
 364                         dogenerate(filename,
 365                                    outFileName, outFilePostfix,
 366                                    flags, i, type,
 367                                    tse1->tse, tid_max);
 368                 }
 369         } else {
 370                 printf("%s: ITERATE ENTIRE HISTORY: %s\n",
 371                        filename, strerror(error));
 372         }
 373         clean_tree(&dir_tree);
 374         clean_tree(&tse_tree);
 375 }
 376
 377 /*
 378  * Generate output for a file as-of ts1 (ts1 may be 0!), if diffing then
 379  * through ts2.
 380  */
 381 static
 382 void
 383 dogenerate(const char *filename, const char *outFileName,
 384            const char *outFilePostfix,
 385            int flags, int idx, enum undo_type type,
 386            struct hammer_ioc_hist_entry ts1,
 387            struct hammer_ioc_hist_entry ts2)
 388 {
 389         struct stat st;
 390         const char *elm;
 391         char *ipath1 = NULL;
 392         char *ipath2 = NULL;
 393         FILE *fi;
 394         FILE *fp;
 395         char *buf;
 396         char *path;
 397         time_t t;
 398         struct tm *tp;
 399         char datestr[64];
 400         int n;
 401
 402         buf = malloc(8192);
 403
 404         /*
 405          * Open the input file.  If ts1 is 0 try to locate the most recent
 406          * version of the file prior to the current version.
 407          */
 408         if (ts1.tid == 0)
 409                 asprintf(&ipath1, "%s", filename);
 410         else
 411                 asprintf(&ipath1, "%s@@0x%016jx", filename, (uintmax_t)ts1.tid);
 412
 413         if (ts2.tid == 0)
 414                 asprintf(&ipath2, "%s", filename);
 415         else
 416                 asprintf(&ipath2, "%s@@0x%016jx", filename, (uintmax_t)ts2.tid);
 417
 418         if (lstat(ipath1, &st) < 0 && lstat(ipath2, &st) < 0) {
 419                 if (idx == 0 || VerboseOpt) {
 420                         fprintf(stderr, "Unable to access either %s or %s\n",
 421                                 ipath1, ipath2);
 422                 }
 423                 free(ipath1);
 424                 free(ipath2);
 425                 goto done;
 426         }
 427
 428         /*
 429          * elm is the last component of the input file name
 430          */
 431         if ((elm = strrchr(filename, '/')) != NULL)
 432                 ++elm;
 433         else
 434                 elm = filename;
 435
 436         /*
 437          * Where do we stuff our output?
 438          */
 439         if (outFileName) {
 440                 if (flags & UNDO_FLAG_MULT) {
 441                         asprintf(&path, outFileName, elm);
 442                         fp = fopen(path, "w");
 443                         if (fp == NULL) {
 444                                 perror(path);
 445                                 exit(1);
 446                         }
 447                         free(path);
 448                 } else {
 449                         fp = fopen(outFileName, "w");
 450                         if (fp == NULL) {
 451                                 perror(outFileName);
 452                                 exit(1);
 453                         }
 454                 }
 455         } else if (outFilePostfix) {
 456                 if (idx >= 0) {
 457                         asprintf(&path, "%s%s.%04d", filename,
 458                                  outFilePostfix, idx);
 459                 } else {
 460                         asprintf(&path, "%s%s", filename, outFilePostfix);
 461                 }
 462                 fp = fopen(path, "w");
 463                 if (fp == NULL) {
 464                         perror(path);
 465                         exit(1);
 466                 }
 467                 free(path);
 468         } else {
 469                 if ((flags & UNDO_FLAG_MULT) && type == TYPE_FILE) {
 470                         if (idx >= 0) {
 471                                 printf("\n>>> %s %04d 0x%016jx %s\n\n",
 472                                        filename, idx, (uintmax_t)ts1.tid,
 473                                        timestamp(&ts1));
 474                         } else {
 475                                 printf("\n>>> %s ---- 0x%016jx %s\n\n",
 476                                        filename, (uintmax_t)ts1.tid,
 477                                        timestamp(&ts1));
 478                         }
 479                 } else if (idx >= 0 && type == TYPE_FILE) {
 480                         printf("\n>>> %s %04d 0x%016jx %s\n\n",
 481                                filename, idx, (uintmax_t)ts1.tid,
 482                                timestamp(&ts1));
 483                 }
 484                 fp = stdout;
 485         }
 486
 487         switch(type) {
 488         case TYPE_FILE:
 489                 if ((fi = fopen(ipath1, "r")) != NULL) {
 490                         while ((n = fread(buf, 1, 8192, fi)) > 0)
 491                                 fwrite(buf, 1, n, fp);
 492                         fclose(fi);
 493                 }
 494                 break;
 495         case TYPE_DIFF:
 496                 printf("diff -N -r -u %s %s (to %s)\n",
 497                        ipath1, ipath2, timestamp(&ts2));
 498                 fflush(stdout);
 499                 runcmd(fileno(fp), "/usr/bin/diff", "diff", "-N", "-r", "-u", ipath1, ipath2, NULL);
 500                 break;
 501         case TYPE_RDIFF:
 502                 printf("diff -N -r -u %s %s\n", ipath2, ipath1);
 503                 fflush(stdout);
 504                 runcmd(fileno(fp), "/usr/bin/diff", "diff", "-N", "-r", "-u", ipath2, ipath1, NULL);
 505                 break;
 506         case TYPE_HISTORY:
 507                 t = (time_t)ts1.time32;
 508                 tp = localtime(&t);
 509                 strftime(datestr, sizeof(datestr), "%d-%b-%Y %H:%M:%S", tp);
 510                 printf("\t0x%016jx %s", (uintmax_t)ts1.tid, datestr);
 511                 if (flags & UNDO_FLAG_INOCHG)
 512                         printf(" inode-change");
 513                 if (lstat(ipath1, &st) < 0)
 514                         printf(" file-deleted");
 515                 printf("\n");
 516                 break;
 517         }
 518
 519         if (fp != stdout)
 520                 fclose(fp);
 521 done:
 522         free(buf);
 523 }
 524
 525 static
 526 void
 527 clean_tree(struct undo_hist_entry_rb_tree *tree)
 528 {
 529         struct undo_hist_entry *tse;
 530
 531         while ((tse = RB_ROOT(tree)) != NULL) {
 532                 RB_REMOVE(undo_hist_entry_rb_tree, tree, tse);
 533                 free(tse);
 534         }
 535 }
 536
 537 static
 538 void
 539 collect_history(int fd, int *errorp, struct undo_hist_entry_rb_tree *tse_tree)
 540 {
 541         struct hammer_ioc_history hist;
 542         struct undo_hist_entry *tse;
 543         struct stat st;
 544         int istmp;
 545         int i;
 546
 547         /*
 548          * Setup
 549          */
 550         bzero(&hist, sizeof(hist));
 551         hist.beg_tid = HAMMER_MIN_TID;
 552         hist.end_tid = HAMMER_MAX_TID;
 553         hist.head.flags |= HAMMER_IOC_HISTORY_ATKEY;
 554         hist.key = 0;
 555         hist.nxt_key = HAMMER_MAX_KEY;
 556
 557         *errorp = 0;
 558
 559         if (tse_tree == NULL) {
 560                 tse_tree = malloc(sizeof(*tse_tree));
 561                 RB_INIT(tse_tree);
 562                 istmp = 1;
 563         } else {
 564                 istmp = 0;
 565         }
 566
 567         /*
 568          * Save the inode so inode changes can be reported.
 569          */
 570         st.st_ino = 0;
 571         fstat(fd, &st);
 572
 573         /*
 574          * Collect a unique set of transaction ids
 575          */
 576         if (ioctl(fd, HAMMERIOC_GETHISTORY, &hist) < 0) {
 577                 *errorp = errno;
 578                 goto done;
 579         }
 580         for (;;) {
 581                 for (i = 0; i < hist.count; ++i) {
 582                         tse = malloc(sizeof(*tse));
 583                         tse->tse = hist.hist_ary[i];
 584                         tse->inum = st.st_ino;
 585                         if (RB_INSERT(undo_hist_entry_rb_tree, tse_tree, tse)) {
 586                                 free(tse);
 587                         }
 588                 }
 589                 if (hist.head.flags & HAMMER_IOC_HISTORY_EOF)
 590                         break;
 591                 if (hist.head.flags & HAMMER_IOC_HISTORY_NEXT_KEY) {
 592                         hist.key = hist.nxt_key;
 593                         hist.nxt_key = HAMMER_MAX_KEY;
 594                 }
 595                 if (hist.head.flags & HAMMER_IOC_HISTORY_NEXT_TID)
 596                         hist.beg_tid = hist.nxt_tid;
 597                 if (ioctl(fd, HAMMERIOC_GETHISTORY, &hist) < 0) {
 598                         *errorp = errno;
 599                         break;
 600                 }
 601         }
 602
 603         /*
 604          * Cleanup
 605          */
 606 done:
 607         if (istmp) {
 608                 clean_tree(tse_tree);
 609                 free(tse_tree);
 610         }
 611 }
 612
 613 static
 614 void
 615 collect_dir_history(const char *filename, int *errorp,
 616                     struct undo_hist_entry_rb_tree *dir_tree)
 617 {
 618         char *dirname;
 619         int fd;
 620         int error;
 621
 622         *errorp = 0;
 623         if (strrchr(filename, '/')) {
 624                 dirname = strdup(filename);
 625                 *strrchr(dirname, '/') = 0;
 626         } else {
 627                 dirname = strdup(".");
 628         }
 629         if ((fd = open(dirname, O_RDONLY)) > 0) {
 630                 collect_history(fd, &error, dir_tree);
 631                 close(fd);
 632         }
 633 }
 634
 635 static
 636 hammer_tid_t
 637 parse_delta_time(const char *timeStr, int *flags, int ind_flag)
 638 {
 639         hammer_tid_t tid;
 640
 641         tid = strtoull(timeStr, NULL, 0);
 642         if (timeStr[0] == '+')
 643                 ++timeStr;
 644         if (timeStr[0] >= '0' && timeStr[0] <= '9' && timeStr[1] != 'x')
 645                 *flags |= ind_flag;
 646         return(tid);
 647 }
 648
 649 static void
 650 runcmd(int fd, const char *cmd, ...)
 651 {
 652         va_list va;
 653         pid_t pid;
 654         char **av;
 655         int ac;
 656         int i;
 657
 658         va_start(va, cmd);
 659         for (ac = 0; va_arg(va, void *) != NULL; ++ac)
 660                 ;
 661         va_end(va);
 662
 663         av = malloc((ac + 1) * sizeof(char *));
 664         va_start(va, cmd);
 665         for (i = 0; i < ac; ++i)
 666                 av[i] = va_arg(va, char *);
 667         va_end(va);
 668         av[i] = NULL;
 669
 670         if ((pid = fork()) < 0) {
 671                 perror("fork");
 672                 exit(1);
 673         } else if (pid == 0) {
 674                 if (fd != 1) {
 675                         dup2(fd, 1);
 676                         close(fd);
 677                 }
 678                 execv(cmd, av);
 679                 _exit(1);
 680         } else {
 681                 while (waitpid(pid, NULL, 0) != pid)
 682                         ;
 683         }
 684         free(av);
 685 }
 686
 687 /*
 688  * Convert tid to timestamp.
 689  */
 690 static char *
 691 timestamp(hammer_ioc_hist_entry_t hen)
 692 {
 693         static char timebuf[64];
 694         time_t t = (time_t)hen->time32;
 695         struct tm *tp;
 696
 697         tp = localtime(&t);
 698         strftime(timebuf, sizeof(timebuf), "%d-%b-%Y %H:%M:%S", tp);
 699         return(timebuf);
 700 }
 701
 702 static
 703 int
 704 undo_hist_entry_compare(struct undo_hist_entry *he1,
 705                         struct undo_hist_entry *he2)
 706 {
 707         if (he1->tse.tid < he2->tse.tid)
 708                 return(-1);
 709         if (he1->tse.tid > he2->tse.tid)
 710                 return(1);
 711         return(0);
 712 }
 713
 714 static void
 715 usage(void)
 716 {
 717         fprintf(stderr, "undo [-adDiuv] [-o outfile] "
 718                         "[-t transaction-id] [-t transaction-id] path...\n"
 719                         "    -a       Iterate all historical segments\n"
 720                         "    -d       Forward diff\n"
 721                         "    -D       Reverse diff\n"
 722                         "    -i       Dump history transaction ids\n"
 723                         "    -u       Generate .undo files\n"
 724                         "    -v       Verbose\n"
 725                         "    -o file  Output to the specified file\n"
 726                         "    -t TID   Retrieve as of transaction-id, TID\n"
 727                         "             (a second `-t TID' to diff two)\n"
 728                         "    transaction ids must be prefixed with 0x, and\n"
 729                         "    otherwise may specify an index starting at 0\n"
 730                         "    and iterating backwards through the history.\n"
 731         );
 732         exit(1);
 733 }
 734