debugfs/util.c

   1 /*
   2  * util.c --- utilities for the debugfs program
   3  *
   4  * Copyright (C) 1993, 1994 Theodore Ts'o.  This file may be
   5  * redistributed under the terms of the GNU Public License.
   6  *
   7  */
   8
   9 #define _XOPEN_SOURCE 600 /* needed for strptime */
  10
  11 #include "config.h"
  12 #include <stdio.h>
  13 #include <unistd.h>
  14 #include <stdlib.h>
  15 #include <ctype.h>
  16 #include <string.h>
  17 #include <time.h>
  18 #include <signal.h>
  19 #ifdef HAVE_GETOPT_H
  20 #include <getopt.h>
  21 #else
  22 extern int optind;
  23 extern char *optarg;
  24 #endif
  25 #ifdef HAVE_OPTRESET
  26 extern int optreset;            /* defined by BSD, but not others */
  27 #endif
  28
  29 #include "ss/ss.h"
  30 #include "debugfs.h"
  31
  32 /*
  33  * This function resets the libc getopt() function, which keeps
  34  * internal state.  Bad design!  Stupid libc API designers!  No
  35  * biscuit!
  36  *
  37  * BSD-derived getopt() functions require that optind be reset to 1 in
  38  * order to reset getopt() state.  This used to be generally accepted
  39  * way of resetting getopt().  However, glibc's getopt()
  40  * has additional getopt() state beyond optind, and requires that
  41  * optind be set zero to reset its state.  So the unfortunate state of
  42  * affairs is that BSD-derived versions of getopt() misbehave if
  43  * optind is set to 0 in order to reset getopt(), and glibc's getopt()
  44  * will core dump if optind is set 1 in order to reset getopt().
  45  *
  46  * More modern versions of BSD require that optreset be set to 1 in
  47  * order to reset getopt().   Sigh.  Standards, anyone?
  48  *
  49  * We hide the hair here.
  50  */
  51 void reset_getopt(void)
  52 {
  53 #if defined(__GLIBC__) || defined(__linux__)
  54         optind = 0;
  55 #else
  56         optind = 1;
  57 #endif
  58 #ifdef HAVE_OPTRESET
  59         optreset = 1;           /* Makes BSD getopt happy */
  60 #endif
  61 }
  62
  63 static const char *pager_search_list[] = { "pager", "more", "less", 0 };
  64 static const char *pager_dir_list[] = { "/usr/bin", "/bin", 0 };
  65
  66 static const char *find_pager(char *buf)
  67 {
  68         const char **i, **j;
  69
  70         for (i = pager_search_list; *i; i++) {
  71                 for (j = pager_dir_list; *j; j++) {
  72                         sprintf(buf, "%s/%s", *j, *i);
  73                         if (access(buf, X_OK) == 0)
  74                                 return(buf);
  75                 }
  76         }
  77         return 0;
  78 }
  79
  80 FILE *open_pager(void)
  81 {
  82         FILE *outfile = 0;
  83         const char *pager = ss_safe_getenv("DEBUGFS_PAGER");
  84         char buf[80];
  85
  86         signal(SIGPIPE, SIG_IGN);
  87         if (!isatty(1))
  88                 return stdout;
  89         if (!pager)
  90                 pager = ss_safe_getenv("PAGER");
  91         if (!pager)
  92                 pager = find_pager(buf);
  93         if (!pager ||
  94             (strcmp(pager, "__none__") == 0) ||
  95             ((outfile = popen(pager, "w")) == 0))
  96                 return stdout;
  97         return outfile;
  98 }
  99
 100 void close_pager(FILE *stream)
 101 {
 102         if (stream && stream != stdout) pclose(stream);
 103 }
 104
 105 /*
 106  * This routine is used whenever a command needs to turn a string into
 107  * an inode.
 108  */
 109 ext2_ino_t string_to_inode(char *str)
 110 {
 111         ext2_ino_t      ino;
 112         int             len = strlen(str);
 113         char            *end;
 114         int             retval;
 115
 116         /*
 117          * If the string is of the form <ino>, then treat it as an
 118          * inode number.
 119          */
 120         if ((len > 2) && (str[0] == '<') && (str[len-1] == '>')) {
 121                 ino = strtoul(str+1, &end, 0);
 122                 if (*end=='>')
 123                         return ino;
 124         }
 125
 126         retval = ext2fs_namei(current_fs, root, cwd, str, &ino);
 127         if (retval) {
 128                 com_err(str, retval, 0);
 129                 return 0;
 130         }
 131         return ino;
 132 }
 133
 134 /*
 135  * This routine returns 1 if the filesystem is not open, and prints an
 136  * error message to that effect.
 137  */
 138 int check_fs_open(char *name)
 139 {
 140         if (!current_fs) {
 141                 com_err(name, 0, "Filesystem not open");
 142                 return 1;
 143         }
 144         return 0;
 145 }
 146
 147 /*
 148  * This routine returns 1 if a filesystem is open, and prints an
 149  * error message to that effect.
 150  */
 151 int check_fs_not_open(char *name)
 152 {
 153         if (current_fs) {
 154                 com_err(name, 0,
 155                         "Filesystem %s is still open.  Close it first.\n",
 156                         current_fs->device_name);
 157                 return 1;
 158         }
 159         return 0;
 160 }
 161
 162 /*
 163  * This routine returns 1 if a filesystem is not opened read/write,
 164  * and prints an error message to that effect.
 165  */
 166 int check_fs_read_write(char *name)
 167 {
 168         if (!(current_fs->flags & EXT2_FLAG_RW)) {
 169                 com_err(name, 0, "Filesystem opened read/only");
 170                 return 1;
 171         }
 172         return 0;
 173 }
 174
 175 /*
 176  * This routine returns 1 if a filesystem is doesn't have its inode
 177  * and block bitmaps loaded, and prints an error message to that
 178  * effect.
 179  */
 180 int check_fs_bitmaps(char *name)
 181 {
 182         if (!current_fs->block_map || !current_fs->inode_map) {
 183                 com_err(name, 0, "Filesystem bitmaps not loaded");
 184                 return 1;
 185         }
 186         return 0;
 187 }
 188
 189 /*
 190  * This function takes a __u32 time value and converts it to a string,
 191  * using ctime
 192  */
 193 char *time_to_string(__u32 cl)
 194 {
 195         static int      do_gmt = -1;
 196         time_t          t = (time_t) cl;
 197         const char      *tz;
 198
 199         if (do_gmt == -1) {
 200                 /* The diet libc doesn't respect the TZ environemnt variable */
 201                 tz = ss_safe_getenv("TZ");
 202                 if (!tz)
 203                         tz = "";
 204                 do_gmt = !strcmp(tz, "GMT") || !strcmp(tz, "GMT0");
 205         }
 206
 207         return asctime((do_gmt) ? gmtime(&t) : localtime(&t));
 208 }
 209
 210 /*
 211  * Parse a string as a time.  Return ((time_t)-1) if the string
 212  * doesn't appear to be a sane time.
 213  */
 214 time_t string_to_time(const char *arg)
 215 {
 216         struct  tm      ts;
 217         time_t          ret;
 218         char *tmp;
 219
 220         if (strcmp(arg, "now") == 0) {
 221                 return time(0);
 222         }
 223         if (arg[0] == '@') {
 224                 /* interpret it as an integer */
 225                 arg++;
 226         fallback:
 227                 ret = strtoul(arg, &tmp, 0);
 228                 if (*tmp)
 229                         return ((time_t) -1);
 230                 return ret;
 231         }
 232         memset(&ts, 0, sizeof(ts));
 233 #ifdef HAVE_STRPTIME
 234         tmp = strptime(arg, "%Y%m%d%H%M%S", &ts);
 235         if (tmp == NULL)
 236                 goto fallback;
 237 #else
 238         sscanf(arg, "%4d%2d%2d%2d%2d%2d", &ts.tm_year, &ts.tm_mon,
 239                &ts.tm_mday, &ts.tm_hour, &ts.tm_min, &ts.tm_sec);
 240         ts.tm_year -= 1900;
 241         ts.tm_mon -= 1;
 242         if (ts.tm_year < 0 || ts.tm_mon < 0 || ts.tm_mon > 11 ||
 243             ts.tm_mday < 0 || ts.tm_mday > 31 || ts.tm_hour > 23 ||
 244             ts.tm_min > 59 || ts.tm_sec > 61)
 245                 ts.tm_mday = 0;
 246 #endif
 247         ts.tm_isdst = -1;
 248         /* strptime() may only update the specified fields, which does not
 249          * necessarily include ts.tm_yday (%j).  Calculate this if unset:
 250          *
 251          * Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
 252          * 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
 253          *
 254          * Start with 31 days per month.  Even months have only 30 days, but
 255          * reverse in August, subtract one day for those months. February has
 256          * only 28 days, not 30, subtract two days. Add day of month, minus
 257          * one, since day is not finished yet.  Leap years handled afterward. */
 258         if (ts.tm_yday == 0)
 259                 ts.tm_yday = (ts.tm_mon * 31) -
 260                         ((ts.tm_mon - (ts.tm_mon > 7)) / 2) -
 261                         2 * (ts.tm_mon > 1) + ts.tm_mday - 1;
 262         ret = ts.tm_sec + ts.tm_min*60 + ts.tm_hour*3600 + ts.tm_yday*86400 +
 263                 (ts.tm_year-70)*31536000 + ((ts.tm_year-69)/4)*86400 -
 264                 ((ts.tm_year-1)/100)*86400 + ((ts.tm_year+299)/400)*86400;
 265         return ret;
 266 }
 267
 268 /*
 269  * This function will convert a string to an unsigned long, printing
 270  * an error message if it fails, and returning success or failure in err.
 271  */
 272 unsigned long parse_ulong(const char *str, const char *cmd,
 273                           const char *descr, int *err)
 274 {
 275         char            *tmp;
 276         unsigned long   ret;
 277
 278         ret = strtoul(str, &tmp, 0);
 279         if (*tmp == 0) {
 280                 if (err)
 281                         *err = 0;
 282                 return ret;
 283         }
 284         com_err(cmd, 0, "Bad %s - %s", descr, str);
 285         if (err)
 286                 *err = 1;
 287         else
 288                 exit(1);
 289         return 0;
 290 }
 291
 292 /*
 293  * This function will convert a string to an unsigned long long, printing
 294  * an error message if it fails, and returning success or failure in err.
 295  */
 296 unsigned long long parse_ulonglong(const char *str, const char *cmd,
 297                                    const char *descr, int *err)
 298 {
 299         char                    *tmp;
 300         unsigned long long      ret;
 301
 302         ret = strtoull(str, &tmp, 0);
 303         if (*tmp == 0) {
 304                 if (err)
 305                         *err = 0;
 306                 return ret;
 307         }
 308         com_err(cmd, 0, "Bad %s - %s", descr, str);
 309         if (err)
 310                 *err = 1;
 311         else
 312                 exit(1);
 313         return 0;
 314 }
 315
 316 /*
 317  * This function will convert a string to a block number.  It returns
 318  * 0 on success, 1 on failure.  On failure, it outputs either an optionally
 319  * specified error message or a default.
 320  */
 321 int strtoblk(const char *cmd, const char *str, const char *errmsg,
 322              blk64_t *ret)
 323 {
 324         blk64_t blk;
 325         int     err;
 326
 327         if (errmsg == NULL)
 328                 blk = parse_ulonglong(str, cmd, "block number", &err);
 329         else
 330                 blk = parse_ulonglong(str, cmd, errmsg, &err);
 331         *ret = blk;
 332         return err;
 333 }
 334
 335 /*
 336  * This is a common helper function used by the command processing
 337  * routines
 338  */
 339 int common_args_process(int argc, char *argv[], int min_argc, int max_argc,
 340                         const char *cmd, const char *usage, int flags)
 341 {
 342         if (argc < min_argc || argc > max_argc) {
 343                 com_err(argv[0], 0, "Usage: %s %s", cmd, usage);
 344                 return 1;
 345         }
 346         if (flags & CHECK_FS_NOTOPEN) {
 347                 if (check_fs_not_open(argv[0]))
 348                         return 1;
 349         } else {
 350                 if (check_fs_open(argv[0]))
 351                         return 1;
 352         }
 353         if ((flags & CHECK_FS_RW) && check_fs_read_write(argv[0]))
 354                 return 1;
 355         if ((flags & CHECK_FS_BITMAPS) && check_fs_bitmaps(argv[0]))
 356                 return 1;
 357         return 0;
 358 }
 359
 360 /*
 361  * This is a helper function used by do_stat, do_freei, do_seti, and
 362  * do_testi, etc.  Basically, any command which takes a single
 363  * argument which is a file/inode number specifier.
 364  */
 365 int common_inode_args_process(int argc, char *argv[],
 366                               ext2_ino_t *inode, int flags)
 367 {
 368         if (common_args_process(argc, argv, 2, 2, argv[0], "<file>", flags))
 369                 return 1;
 370
 371         *inode = string_to_inode(argv[1]);
 372         if (!*inode)
 373                 return 1;
 374         return 0;
 375 }
 376
 377 /*
 378  * This is a helper function used by do_freeb, do_setb, and do_testb
 379  */
 380 int common_block_args_process(int argc, char *argv[],
 381                               blk64_t *block, blk64_t *count)
 382 {
 383         int     err;
 384
 385         if (common_args_process(argc, argv, 2, 3, argv[0],
 386                                 "<block> [count]", CHECK_FS_BITMAPS))
 387                 return 1;
 388
 389         if (strtoblk(argv[0], argv[1], NULL, block))
 390                 return 1;
 391         if (*block == 0) {
 392                 com_err(argv[0], 0, "Invalid block number 0");
 393                 err = 1;
 394         }
 395
 396         if (argc > 2) {
 397                 err = strtoblk(argv[0], argv[2], "count", count);
 398                 if (err)
 399                         return 1;
 400         }
 401         return 0;
 402 }
 403
 404 int debugfs_read_inode_full(ext2_ino_t ino, struct ext2_inode * inode,
 405                         const char *cmd, int bufsize)
 406 {
 407         int retval;
 408
 409         retval = ext2fs_read_inode_full(current_fs, ino, inode, bufsize);
 410         if (retval) {
 411                 com_err(cmd, retval, "while reading inode %u", ino);
 412                 return 1;
 413         }
 414         return 0;
 415 }
 416
 417 int debugfs_read_inode(ext2_ino_t ino, struct ext2_inode * inode,
 418                         const char *cmd)
 419 {
 420         int retval;
 421
 422         retval = ext2fs_read_inode(current_fs, ino, inode);
 423         if (retval) {
 424                 com_err(cmd, retval, "while reading inode %u", ino);
 425                 return 1;
 426         }
 427         return 0;
 428 }
 429
 430 int debugfs_write_inode_full(ext2_ino_t ino,
 431                              struct ext2_inode *inode,
 432                              const char *cmd,
 433                              int bufsize)
 434 {
 435         int retval;
 436
 437         retval = ext2fs_write_inode_full(current_fs, ino,
 438                                          inode, bufsize);
 439         if (retval) {
 440                 com_err(cmd, retval, "while writing inode %u", ino);
 441                 return 1;
 442         }
 443         return 0;
 444 }
 445
 446 int debugfs_write_inode(ext2_ino_t ino, struct ext2_inode * inode,
 447                         const char *cmd)
 448 {
 449         int retval;
 450
 451         retval = ext2fs_write_inode(current_fs, ino, inode);
 452         if (retval) {
 453                 com_err(cmd, retval, "while writing inode %u", ino);
 454                 return 1;
 455         }
 456         return 0;
 457 }
 458
 459 int debugfs_write_new_inode(ext2_ino_t ino, struct ext2_inode * inode,
 460                             const char *cmd)
 461 {
 462         int retval;
 463
 464         retval = ext2fs_write_new_inode(current_fs, ino, inode);
 465         if (retval) {
 466                 com_err(cmd, retval, "while creating inode %u", ino);
 467                 return 1;
 468         }
 469         return 0;
 470 }
 471
 472 /*
 473  * Given a mode, return the ext2 file type
 474  */
 475 int ext2_file_type(unsigned int mode)
 476 {
 477         if (LINUX_S_ISREG(mode))
 478                 return EXT2_FT_REG_FILE;
 479
 480         if (LINUX_S_ISDIR(mode))
 481                 return EXT2_FT_DIR;
 482
 483         if (LINUX_S_ISCHR(mode))
 484                 return EXT2_FT_CHRDEV;
 485
 486         if (LINUX_S_ISBLK(mode))
 487                 return EXT2_FT_BLKDEV;
 488
 489         if (LINUX_S_ISLNK(mode))
 490                 return EXT2_FT_SYMLINK;
 491
 492         if (LINUX_S_ISFIFO(mode))
 493                 return EXT2_FT_FIFO;
 494
 495         if (LINUX_S_ISSOCK(mode))
 496                 return EXT2_FT_SOCK;
 497
 498         return 0;
 499 }