+ return fail;
+}
+
+/* The length of this name must be 8. */
+#define DIR_NAME "confdir3"
+#define DIR_NAME_LEN 8
+#define DIR_NAME_SIZE (DIR_NAME_LEN + 1)
+
+/* The length of "../". */
+#define DOTDOTSLASH_LEN 3
+
+/* Leftover bytes in the buffer, to work around library or OS bugs. */
+#define BUF_SLOP 20
+
+/* Keep this test in sync with m4/getcwd-path-max.m4. */
+static int
+test_long_name (void)
+{
+#ifndef PATH_MAX
+ /* The Hurd doesn't define this, so getcwd can't exhibit the bug --
+ at least not on a local file system. And if we were to start worrying
+ about remote file systems, we'd have to enable the wrapper function
+ all of the time, just to be safe. That's not worth the cost. */
+ return 0;
+#elif ((INT_MAX / (DIR_NAME_SIZE / DOTDOTSLASH_LEN + 1) \
+ - DIR_NAME_SIZE - BUF_SLOP) \
+ <= PATH_MAX)
+ /* FIXME: Assuming there's a system for which this is true,
+ this should be done in a compile test. */
+ return 0;
+#else
+ char buf[PATH_MAX * (DIR_NAME_SIZE / DOTDOTSLASH_LEN + 1)
+ + DIR_NAME_SIZE + BUF_SLOP];
+ char *cwd = getcwd (buf, PATH_MAX);
+ size_t initial_cwd_len;
+ size_t cwd_len;
+ int fail = 0;
+ size_t n_chdirs = 0;
+
+ if (cwd == NULL)
+ return 1;
+
+ cwd_len = initial_cwd_len = strlen (cwd);
+
+ while (1)
+ {
+ size_t dotdot_max = PATH_MAX * (DIR_NAME_SIZE / DOTDOTSLASH_LEN);
+ char *c = NULL;
+
+ cwd_len += DIR_NAME_SIZE;
+ /* If mkdir or chdir fails, it could be that this system cannot create
+ any file with an absolute name longer than PATH_MAX, such as cygwin.
+ If so, leave fail as 0, because the current working directory can't
+ be too long for getcwd if it can't even be created. For other
+ errors, be pessimistic and consider that as a failure, too. */
+ if (mkdir (DIR_NAME, S_IRWXU) < 0 || chdir (DIR_NAME) < 0)
+ {
+ if (! (errno == ERANGE || errno == ENAMETOOLONG || errno == ENOENT))
+ fail = 2;
+ break;
+ }
+
+ if (PATH_MAX <= cwd_len && cwd_len < PATH_MAX + DIR_NAME_SIZE)
+ {
+ c = getcwd (buf, PATH_MAX);
+ if (!c && errno == ENOENT)
+ {
+ fail = 3;
+ break;
+ }
+ if (c)
+ {
+ fail = 4;
+ break;
+ }
+ if (! (errno == ERANGE || errno == ENAMETOOLONG))
+ {
+ fail = 5;
+ break;
+ }
+ }