LXR toybox/toys/posix/rm.c

   1/* rm.c - remove files
   2 *
   3 * Copyright 2012 Rob Landley <rob@landley.net>
   4 *
   5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/rm.html
   6
   7USE_RM(NEWTOY(rm, "fiRrv[-fi]", TOYFLAG_BIN))
   8
   9config RM
  10  bool "rm"
  11  default y
  12  help
  13    usage: rm [-fiRrv] FILE...
  14
  15    Remove each argument from the filesystem.
  16
  17    -f  Force: remove without confirmation, no error if it doesn't exist
  18    -i  Interactive: prompt for confirmation
  19    -rR Recursive: remove directory contents
  20    -v  Verbose
  21*/
  22
  23#define FOR_rm
  24#include "toys.h"
  25
  26static int do_rm(struct dirtree *try)
  27{
  28  int fd = dirtree_parentfd(try), flags = toys.optflags;
  29  int dir = S_ISDIR(try->st.st_mode), or = 0, using = 0;
  30
  31  // Skip . and .. (yes, even explicitly on the command line: posix says to)
  32  if (isdotdot(try->name)) return 0;
  33
  34  // Intentionally fail non-recursive attempts to remove even an empty dir
  35  // (via wrong flags to unlinkat) because POSIX says to.
  36  if (dir && !(flags & (FLAG_r|FLAG_R))) goto skip;
  37
  38  // This is either the posix section 2(b) prompt or the section 3 prompt.
  39  if (!(flags & FLAG_f)
  40    && (!S_ISLNK(try->st.st_mode) && faccessat(fd, try->name, W_OK, 0))) or++;
  41  if (!(dir && try->again) && ((or && isatty(0)) || (flags & FLAG_i))) {
  42    char *s = dirtree_path(try, 0);
  43
  44    fprintf(stderr, "rm %s%s%s", or ? "ro " : "", dir ? "dir " : "", s);
  45    free(s);
  46    or = yesno(0);
  47    if (!or) goto nodelete;
  48  }
  49
  50  // handle directory recursion
  51  if (dir) {
  52    using = AT_REMOVEDIR;
  53    // Handle chmod 000 directories when -f
  54    if (faccessat(fd, try->name, R_OK, 0)) {
  55      if (toys.optflags & FLAG_f) wfchmodat(fd, try->name, 0700);
  56      else goto skip;
  57    }
  58    if (!try->again) return DIRTREE_COMEAGAIN;
  59    if (try->symlink) goto skip;
  60    if (flags & FLAG_i) {
  61      char *s = dirtree_path(try, 0);
  62
  63      // This is the section 2(d) prompt. (Yes, posix says to prompt twice.)
  64      fprintf(stderr, "rmdir %s", s);
  65      free(s);
  66      or = yesno(0);
  67      if (!or) goto nodelete;
  68    }
  69  }
  70
  71skip:
  72  if (!unlinkat(fd, try->name, using)) {
  73    if (flags & FLAG_v) {
  74      char *s = dirtree_path(try, 0);
  75      printf("%s%s '%s'\n", toys.which->name, dir ? "dir" : "", s);
  76      free(s);
  77    }
  78  } else {
  79    if (!dir || try->symlink != (char *)2) perror_msg_raw(try->name);
  80nodelete:
  81    if (try->parent) try->parent->symlink = (char *)2;
  82  }
  83
  84  return 0;
  85}
  86
  87void rm_main(void)
  88{
  89  char **s;
  90
  91  // Can't use <1 in optstring because zero arguments with -f isn't an error
  92  if (!toys.optc && !(toys.optflags & FLAG_f)) error_exit("Needs 1 argument");
  93
  94  for (s = toys.optargs; *s; s++) {
  95    if (!strcmp(*s, "/")) {
  96      error_msg("rm /. if you mean it");
  97      continue;
  98    }
  99
 100    // Files that already don't exist aren't errors for -f, so try a quick
 101    // unlink now to see if it succeeds or reports that it didn't exist.
 102    if ((toys.optflags & FLAG_f) && (!unlink(*s) || errno == ENOENT))
 103      continue;
 104
 105    // There's a race here where a file removed between the above check and
 106    // dirtree's stat would report the nonexistence as an error, but that's
 107    // not a normal "it didn't exist" so I'm ok with it.
 108
 109    dirtree_read(*s, do_rm);
 110  }
 111}
 112