X-Git-Url: https://git.cworth.org/git?p=tar;a=blobdiff_plain;f=gnu%2Fgetcwd.c;fp=gnu%2Fgetcwd.c;h=2ccca7963e27a8caeae0b9703f788e6fbc401eb9;hp=504448fce245fa58b1a829e98b93ee4c4c3ca724;hb=b414e25de8ca49d7567a92c203d431383ec57c83;hpb=29ece34f44a27750bbfd76154ad9882580453dc7

diff --git a/gnu/getcwd.c b/gnu/getcwd.c
index 504448f..2ccca79 100644
--- a/gnu/getcwd.c
+++ b/gnu/getcwd.c
@@ -138,13 +138,11 @@ __getcwd (char *buf, size_t size)
   size_t allocated = size;
   size_t used;
 
-#if HAVE_PARTLY_WORKING_GETCWD
-  /* The system getcwd works, except it sometimes fails when it
-     shouldn't, setting errno to ERANGE, ENAMETOOLONG, or ENOENT.  If
-     AT_FDCWD is not defined, the algorithm below is O(N**2) and this
-     is much slower than the system getcwd (at least on GNU/Linux).
-     So trust the system getcwd's results unless they look
-     suspicious.
+#if HAVE_RAW_DECL_GETCWD
+  /* If AT_FDCWD is not defined, the algorithm below is O(N**2) and
+     this is much slower than the system getcwd (at least on
+     GNU/Linux).  So trust the system getcwd's results unless they
+     look suspicious.
 
      Use the system getcwd even if we have openat support, since the
      system getcwd works even when a parent is unreadable, while the
@@ -152,8 +150,27 @@ __getcwd (char *buf, size_t size)
 
 # undef getcwd
   dir = getcwd (buf, size);
-  if (dir || (errno != ERANGE && errno != ENAMETOOLONG && errno != ENOENT))
+  if (dir)
     return dir;
+
+  /* Solaris getcwd (NULL, 0) fails with errno == EINVAL, but it has
+     internal magic that lets it work even if an ancestor directory is
+     inaccessible, which is better in many cases.  So in this case try
+     again with a buffer that's almost always big enough.  */
+  if (errno == EINVAL && buf == NULL && size == 0)
+    {
+      char big_buffer[BIG_FILE_NAME_LENGTH + 1];
+      dir = getcwd (big_buffer, sizeof big_buffer);
+      if (dir)
+        return strdup (dir);
+    }
+
+# if HAVE_PARTLY_WORKING_GETCWD
+  /* The system getcwd works, except it sometimes fails when it
+     shouldn't, setting errno to ERANGE, ENAMETOOLONG, or ENOENT.    */
+  if (errno != ERANGE && errno != ENAMETOOLONG && errno != ENOENT)
+    return NULL;
+# endif
 #endif
 
   if (size == 0)
@@ -232,8 +249,6 @@ __getcwd (char *buf, size_t size)
       dirstream = fdopendir (fd);
       if (dirstream == NULL)
         goto lose;
-      /* Reset fd.  It may have been closed by fdopendir.  */
-      fd = dirfd (dirstream);
       fd_needs_closing = false;
 #else
       dirstream = __opendir (dotlist);