Libc-1439.100.3.tar.gz

[apple/libc.git] / gen / FreeBSD / getcwd.c

diff --git a/gen/FreeBSD/getcwd.c b/gen/FreeBSD/getcwd.c
index 4a1989026b67df4e10f5b768c946d1646b5612ee..3951c7bf7a8185b15fc08797f5c58df5b3a6cd41 100644 (file)
--- a/gen/FreeBSD/getcwd.c
+++ b/gen/FreeBSD/getcwd.c
@@ -49,10 +49,48 @@ __FBSDID("$FreeBSD: src/lib/libc/gen/getcwd.c,v 1.29 2007/01/09 00:27:53 imp Exp
 #include <unistd.h>
 #include "un-namespace.h"
 
+#if TARGET_OS_OSX && !TARGET_OS_SIMULATOR
+#include <sys/attr.h>  /* for FSOPT_NOFOLLOW */
+#include <apfs/apfs_fsctl.h>
+#endif
+
 #define        ISDOT(dp) \
        (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \
            (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
 
+/*
+ * Check if the given directory is a firmlink.
+ * Return 1 if it is firmlink otherwise return 0.
+ */
+static inline int
+__check_for_firmlink(char *dir_path)
+{
+#if TARGET_OS_OSX && !TARGET_OS_SIMULATOR
+       apfs_firmlink_control_t afc;
+       int is_firmlink;
+       int err;
+
+       afc.cmd = FIRMLINK_GET;
+       afc.val = 0;
+
+       err = fsctl(dir_path, APFSIOC_FIRMLINK_CTL, (void *)&afc, FSOPT_NOFOLLOW);
+       if (err == 0) {
+               is_firmlink = afc.val ? 1 : 0;
+       } else  {
+               /*
+                * On error, we assume it is a firmlink. This could be a false positive
+                * and we will end up incurring a lstat() cost but it will give us some
+                * chance to build the path successfully.
+                */
+               is_firmlink = 1;
+       }
+
+       return is_firmlink;
+#else
+       return 0;
+#endif
+}
+
 /*
  * If __getcwd() ever becomes a syscall, we can remove this workaround.
  * The problem here is that fcntl() assumes a buffer of size MAXPATHLEN,
@@ -253,8 +291,29 @@ __private_getcwd(pt, size, usegetpath)
                        for (;;) {
                                if (!(dp = readdir(dir)))
                                        goto notfound;
-                               if (dp->d_fileno == ino)
+                               if (dp->d_fileno == ino) {
                                        break;
+                               } else if (!ISDOT(dp) && dp->d_type == DT_DIR) {
+                                       /*
+                                        * The 'd_fileno' for firmlink directory would be different
+                                        * than the 'st_ino' returned by stat(). We have to do an
+                                        * extra lstat() on firmlink directory to determine if the
+                                        * 'st_ino' matches with what we are looking for.
+                                        */
+                    bcopy(dp->d_name, bup, dp->d_namlen + 1);
+
+                                       if (__check_for_firmlink(up) == 0)
+                                               continue;
+
+                    if (lstat(up, &s)) {
+                        if (!save_errno)
+                            save_errno = errno;
+                        errno = 0;
+                        continue;
+                    }
+                    if (s.st_dev == dev && s.st_ino == ino)
+                        break;
+                }
                        }
                } else
                        for (;;) {