From d598f8169bbc9178c59d35f0df95637a70d3377f Mon Sep 17 00:00:00 2001
From: Zach van Rijn <me@zv.io>
Date: Mon, 10 Apr 2023 04:09:56 -0500
Subject: [PATCH] Revert "getcwd: Speed up on Linux. Add support for Android."
This reverts commit 356a414e8c15ef3f8cc7b7157427c8ce9a9f7c1b.
diff --git a/lib/getcwd.c b/lib/getcwd.c
index 0530630c43..04b8d2df39 100644
--- a/lib/getcwd.c
+++ b/lib/getcwd.c
@@ -173,9 +173,6 @@ __getcwd_generic (char *buf, size_t size)
#if HAVE_OPENAT_SUPPORT
int fd = AT_FDCWD;
bool fd_needs_closing = false;
-# if defined __linux__
- bool proc_fs_not_mounted = false;
-# endif
#else
char dots[DEEP_NESTING * sizeof ".." + BIG_FILE_NAME_COMPONENT_LENGTH + 1];
char *dotlist = dots;
@@ -441,67 +438,6 @@ __getcwd_generic (char *buf, size_t size)
thisdev = dotdev;
thisino = dotino;
-
-#if HAVE_OPENAT_SUPPORT
- /* On some platforms, a system call returns the directory that FD points
- to. This is useful if some of the ancestor directories of the
- directory are unreadable, because in this situation the loop that
- climbs up the ancestor hierarchy runs into an EACCES error.
- For example, in some Android app, /data/data/com.termux is readable,
- but /data/data and /data are not. */
-# if defined __linux__
- /* On Linux, in particular, if /proc is mounted,
- readlink ("/proc/self/fd/<fd>")
- returns the directory, if its length is < 4096. (If the length is
- >= 4096, it fails with error ENAMETOOLONG, even if the buffer that we
- pass to the readlink function would be large enough.) */
- if (!proc_fs_not_mounted)
- {
- char namebuf[14 + 10 + 1];
- sprintf (namebuf, "/proc/self/fd/%u", (unsigned int) fd);
- char linkbuf[4096];
- ssize_t linklen = readlink (namebuf, linkbuf, sizeof linkbuf);
- if (linklen < 0)
- {
- if (errno != ENAMETOOLONG)
- /* If this call was not successful, the next one will likely be
- not successful either. */
- proc_fs_not_mounted = true;
- }
- else
- {
- dirroom = dirp - dir;
- if (dirroom < linklen)
- {
- if (size != 0)
- {
- __set_errno (ERANGE);
- goto lose;
- }
- else
- {
- char *tmp;
- size_t oldsize = allocated;
-
- allocated += linklen - dirroom;
- if (allocated < oldsize
- || ! (tmp = realloc (dir, allocated)))
- goto memory_exhausted;
-
- /* Move current contents up to the end of the buffer. */
- dirp = memmove (tmp + dirroom + (allocated - oldsize),
- tmp + dirroom,
- oldsize - dirroom);
- dir = tmp;
- }
- }
- dirp -= linklen;
- memcpy (dirp, linkbuf, linklen);
- break;
- }
- }
-# endif
-#endif
}
if (dirstream && __closedir (dirstream) != 0)
--
2.25.1
