cp: revert a recent buggy change, and add a comment why it's wrong

[oweals/busybox.git] / miscutils / mountpoint.c

diff --git a/miscutils/mountpoint.c b/miscutils/mountpoint.c
index 6265a20e17b81854222fba6c6592ee4c382f5d88..b541ce28c35d1cb05c911fb8b631d8bb6805895a 100644 (file)
--- a/miscutils/mountpoint.c
+++ b/miscutils/mountpoint.c
@@ -2,69 +2,71 @@
 /*
  * mountpoint implementation for busybox
  *
- * Copyright (C) 2005 Bernhard Fischer
+ * Copyright (C) 2005 Bernhard Reutner-Fischer
  *
  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  *
  * Based on sysvinit's mountpoint
  */
 
-#include "busybox.h"
-#include <sys/stat.h>
-#include <errno.h> /* errno */
-#include <string.h> /* strerror */
-#include <getopt.h> /* optind */
+#include "libbb.h"
 
-int mountpoint_main(int argc, char **argv)
+int mountpoint_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int mountpoint_main(int argc UNUSED_PARAM, char **argv)
 {
-       int opt = bb_getopt_ulflags(argc, argv, "qdx");
+       struct stat st;
+       const char *msg;
+       char *arg;
+       int rc, opt;
+
+       opt_complementary = "=1"; /* must have one argument */
+       opt = getopt32(argv, "qdxn");
 #define OPT_q (1)
 #define OPT_d (2)
 #define OPT_x (4)
+#define OPT_n (8)
+       arg = argv[optind];
+       msg = "%s";
+
+       rc = (opt & OPT_x) ? stat(arg, &st) : lstat(arg, &st);
+       if (rc != 0)
+               goto err;
+
+       if (opt & OPT_x) {
+               if (S_ISBLK(st.st_mode)) {
+                       printf("%u:%u\n", major(st.st_rdev),
+                                               minor(st.st_rdev));
+                       return EXIT_SUCCESS;
+               }
+               errno = 0; /* make perror_msg work as error_msg */
+               msg = "%s: not a block device";
+               goto err;
+       }
 
-       if (optind != argc - 1)
-               bb_show_usage();
-       {
-               char *arg = argv[optind];
-               struct stat st;
+       errno = ENOTDIR;
+       if (S_ISDIR(st.st_mode)) {
+               dev_t st_dev = st.st_dev;
+               ino_t st_ino = st.st_ino;
+               char *p = xasprintf("%s/..", arg);
 
-               if ( (opt & OPT_x && stat(arg, &st) == 0) || (lstat(arg, &st) == 0) ) {
-                       if (opt & OPT_x) {
-                               if (S_ISBLK(st.st_mode))
-                               {
-                                       bb_printf("%u:%u\n", major(st.st_rdev),
-                                                               minor(st.st_rdev));
-                                       return EXIT_SUCCESS;
-                               } else {
-                                       if (opt & OPT_q)
-                                               putchar('\n');
-                                       else
-                                               bb_error_msg("%s: not a block device", arg);
-                               }
-                               return EXIT_FAILURE;
-                       } else
-                       if (S_ISDIR(st.st_mode)) {
-                               dev_t st_dev = st.st_dev;
-                               ino_t st_ino = st.st_ino;
-                               char *p = bb_xasprintf("%s/..", arg);
+               if (stat(p, &st) == 0) {
+                       //int is_mnt = (st_dev != st.st_dev) || (st_dev == st.st_dev && st_ino == st.st_ino);
+                       int is_not_mnt = (st_dev == st.st_dev) && (st_ino != st.st_ino);
 
-                               if (stat(p, &st) == 0) {
-                                       short ret = (st_dev != st.st_dev) ||
-                                               (st_dev == st.st_dev && st_ino == st.st_ino);
-                                       if (opt & OPT_d)
-                                               bb_printf("%u:%u\n", major(st_dev), minor(st_dev));
-                                       else if (!(opt & OPT_q))
-                                               bb_printf("%s is %sa mountpoint\n", arg, ret?"":"not ");
-                                       return !ret;
-                               }
-                       } else {
-                               if (!(opt & OPT_q))
-                                       bb_error_msg("%s: not a directory", arg);
-                               return EXIT_FAILURE;
-                       }
+                       if (opt & OPT_d)
+                               printf("%u:%u\n", major(st_dev), minor(st_dev));
+                       if (opt & OPT_n)
+                               printf("%s %s\n", find_block_device(arg), arg);
+                       if (!(opt & (OPT_q | OPT_d | OPT_n)))
+                               printf("%s is %sa mountpoint\n", arg, is_not_mnt ? "not " : "");
+                       return is_not_mnt;
                }
-               if (!(opt & OPT_q))
-                       bb_perror_msg("%s", arg);
-               return EXIT_FAILURE;
+               arg = p;
+               /* else: stat had set errno, just fall through */
        }
+
+ err:
+       if (!(opt & OPT_q))
+               bb_perror_msg(msg, arg);
+       return EXIT_FAILURE;
 }