Hurd compat fixes. Mostly dealing with absent PATH_MAX

Signed-off-by: Jérémie Koenig <jk@jk.fr.eu.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 22 insertions, 11 deletions

diff --git a/util-linux/umount.c b/util-linux/umount.c
index a4b2bd087..a19f86c3a 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -39,6 +39,10 @@
 # define MS_RELATIME    (1 << 21)
 #endif
 #include "libbb.h"
+#ifndef PATH_MAX
+# define PATH_MAX (4*1024)
+#endif
+
 
 #if defined(__dietlibc__)
 /* 16.12.2006, Sampo Kellomaki (sampo@iki.fi)
@@ -69,7 +73,7 @@ int umount_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int umount_main(int argc UNUSED_PARAM, char **argv)
 {
         int doForce;
-        char *const path = xmalloc(PATH_MAX + 2); /* to save stack */
+        char *const buf = xmalloc(PATH_MAX * 2 + 128); /* to save stack */
         struct mntent me;
         FILE *fp;
         char *fstype = NULL;
@@ -100,7 +104,7 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
                 if (opt & OPT_ALL)
                         bb_error_msg_and_die("can't open '%s'", bb_path_mtab_file);
         } else {
-                while (getmntent_r(fp, &me, path, PATH_MAX)) {
+                while (getmntent_r(fp, &me, buf, PATH_MAX * 2 + 128)) {
                         /* Match fstype if passed */
                         if (!match_fstype(&me, fstype))
                                 continue;
@@ -124,10 +128,11 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
         for (;;) {
                 int curstat;
                 char *zapit = *argv;
+                char *path;
 
                 // Do we already know what to umount this time through the loop?
                 if (m)
-                        safe_strncpy(path, m->dir, PATH_MAX);
+                        path = xstrdup(m->dir);
                 // For umount -a, end of mtab means time to exit.
                 else if (opt & OPT_ALL)
                         break;
@@ -136,10 +141,12 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
                         if (!zapit)
                                 break;
                         argv++;
-                        realpath(zapit, path);
-                        for (m = mtl; m; m = m->next)
-                                if (!strcmp(path, m->dir) || !strcmp(path, m->device))
-                                        break;
+                        path = xmalloc_realpath(zapit);
+                        if (path) {
+                                for (m = mtl; m; m = m->next)
+                                        if (strcmp(path, m->dir) == 0 || strcmp(path, m->device) == 0)
+                                                break;
+                        }
                 }
                 // If we couldn't find this sucker in /etc/mtab, punt by passing our
                 // command line argument straight to the umount syscall.  Otherwise,
@@ -181,9 +188,13 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
                 // Find next matching mtab entry for -a or umount /dev
                 // Note this means that "umount /dev/blah" will unmount all instances
                 // of /dev/blah, not just the most recent.
-                if (m) while ((m = m->next) != NULL)
-                        if ((opt & OPT_ALL) || !strcmp(path, m->device))
-                                break;
+                if (m) {
+                        while ((m = m->next) != NULL)
+                                // NB: if m is non-NULL, path is non-NULL as well
+                                if ((opt & OPT_ALL) || strcmp(path, m->device) == 0)
+                                        break;
+                }
+                free(path);
         }
 
         // Free mtab list if necessary
@@ -195,7 +206,7 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
                         free(mtl);
                         mtl = m;
                 }
-                free(path);
+                free(buf);
         }
 
         return status;