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 
7 USE_RM(NEWTOY(rm, "fiRr[-fi]", TOYFLAG_BIN))
8 
9 config RM
10   bool "rm"
11   default y
12   help
13     usage: rm [-fiRr] 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 */
21 
22 #define FOR_rm
23 #include "toys.h"
24 
do_rm(struct dirtree * try)25 static int do_rm(struct dirtree *try)
26 {
27   int fd = dirtree_parentfd(try), flags = toys.optflags;
28   int dir = S_ISDIR(try->st.st_mode), or = 0, using = 0;
29 
30   // Skip . and .. (yes, even explicitly on the command line: posix says to)
31   if (!dirtree_notdotdot(try)) return 0;
32 
33   // Intentionally fail non-recursive attempts to remove even an empty dir
34   // (via wrong flags to unlinkat) because POSIX says to.
35   if (dir && !(flags & (FLAG_r|FLAG_R))) goto skip;
36 
37   // This is either the posix section 2(b) prompt or the section 3 prompt.
38   if (!(flags & FLAG_f)
39     && (!S_ISLNK(try->st.st_mode) && faccessat(fd, try->name, W_OK, 0))) or++;
40   if (!(dir && try->again) && ((or && isatty(0)) || (flags & FLAG_i))) {
41     char *s = dirtree_path(try, 0);
42     fprintf(stderr, "rm %s%s", or ? "ro " : "", dir ? "dir " : "");
43     or = yesno(s, 0);
44     free(s);
45     if (!or) goto nodelete;
46   }
47 
48   // handle directory recursion
49   if (dir) {
50     using = AT_REMOVEDIR;
51     // Handle chmod 000 directories when -f
52     if (faccessat(fd, try->name, R_OK, 0)) {
53       if (toys.optflags & FLAG_f) wfchmodat(fd, try->name, 0700);
54       else goto skip;
55     }
56     if (!try->again) return DIRTREE_COMEAGAIN;
57     if (try->symlink) goto skip;
58     if (flags & FLAG_i) {
59       char *s = dirtree_path(try, 0);
60       // This is the section 2(d) prompt. (Yes, posix says to prompt twice.)
61       fprintf(stderr, "rmdir ");
62       or = yesno(s, 0);
63       free(s);
64       if (!or) goto nodelete;
65     }
66   }
67 
68 skip:
69   if (unlinkat(fd, try->name, using)) {
70     if (!dir || try->symlink != (char *)2) perror_msg("%s", try->name);
71 nodelete:
72     if (try->parent) try->parent->symlink = (char *)2;
73   }
74 
75   return 0;
76 }
77 
rm_main(void)78 void rm_main(void)
79 {
80   char **s;
81 
82   // Can't use <1 in optstring because zero arguments with -f isn't an error
83   if (!toys.optc && !(toys.optflags & FLAG_f)) error_exit("Needs 1 argument");
84 
85   for (s = toys.optargs; *s; s++) {
86     if (!strcmp(*s, "/")) {
87       error_msg("rm /. if you mean it");
88       continue;
89     }
90 
91     // Files that already don't exist aren't errors for -f, so try a quick
92     // unlink now to see if it succeeds or reports that it didn't exist.
93     if ((toys.optflags & FLAG_f) && (!unlink(*s) || errno == ENOENT))
94       continue;
95 
96     // There's a race here where a file removed between the above check and
97     // dirtree's stat would report the nonexistence as an error, but that's
98     // not a normal "it didn't exist" so I'm ok with it.
99 
100     dirtree_read(*s, do_rm);
101   }
102 }
103