+
+/* Depending on DEREF, apply either stat or lstat to (NAME, BUF). */
+int
+deref_stat (bool deref, char const *name, struct stat *buf)
+{
+ return deref ? stat (name, buf) : lstat (name, buf);
+}
+
+/* Set FD's (i.e., FILE's) access time to TIMESPEC[0]. If that's not
+ possible to do by itself, set its access and data modification
+ times to TIMESPEC[0] and TIMESPEC[1], respectively. */
+int
+set_file_atime (int fd, char const *file, struct timespec const timespec[2])
+{
+#ifdef _FIOSATIME
+ if (0 <= fd)
+ {
+ struct timeval timeval;
+ timeval.tv_sec = timespec[0].tv_sec;
+ timeval.tv_usec = timespec[0].tv_nsec / 1000;
+ if (ioctl (fd, _FIOSATIME, &timeval) == 0)
+ return 0;
+ }
+#endif
+
+ return gl_futimens (fd, file, timespec);
+}
+
+/* A description of a working directory. */
+struct wd
+{
+ char const *name;
+ int saved;
+ struct saved_cwd saved_cwd;
+};
+
+/* A vector of chdir targets. wd[0] is the initial working directory. */
+static struct wd *wd;
+
+/* The number of working directories in the vector. */
+static size_t wds;
+
+/* The allocated size of the vector. */
+static size_t wd_alloc;
+
+/* DIR is the operand of a -C option; add it to vector of chdir targets,
+ and return the index of its location. */
+int
+chdir_arg (char const *dir)
+{
+ if (wds == wd_alloc)
+ {
+ if (wd_alloc == 0)
+ {
+ wd_alloc = 2;
+ wd = xmalloc (sizeof *wd * wd_alloc);
+ }
+ else
+ wd = x2nrealloc (wd, &wd_alloc, sizeof *wd);
+
+ if (! wds)
+ {
+ wd[wds].name = ".";
+ wd[wds].saved = 0;
+ wds++;
+ }
+ }
+
+ /* Optimize the common special case of the working directory,
+ or the working directory as a prefix. */
+ if (dir[0])
+ {
+ while (dir[0] == '.' && ISSLASH (dir[1]))
+ for (dir += 2; ISSLASH (*dir); dir++)
+ continue;
+ if (! dir[dir[0] == '.'])
+ return wds - 1;
+ }
+
+ wd[wds].name = dir;
+ wd[wds].saved = 0;
+ return wds++;
+}
+
+/* Change to directory I. If I is 0, change to the initial working
+ directory; otherwise, I must be a value returned by chdir_arg. */
+void
+chdir_do (int i)
+{
+ static int previous;
+
+ if (previous != i)
+ {
+ struct wd *prev = &wd[previous];
+ struct wd *curr = &wd[i];
+
+ if (! prev->saved)
+ {
+ int err = 0;
+ prev->saved = 1;
+ if (save_cwd (&prev->saved_cwd) != 0)
+ err = errno;
+ else if (0 <= prev->saved_cwd.desc)
+ {
+ /* Make sure we still have at least one descriptor available. */
+ int fd1 = prev->saved_cwd.desc;
+ int fd2 = dup (fd1);
+ if (0 <= fd2)
+ close (fd2);
+ else if (errno == EMFILE)
+ {
+ /* Force restore_cwd to use chdir_long. */
+ close (fd1);
+ prev->saved_cwd.desc = -1;
+ prev->saved_cwd.name = xgetcwd ();
+ }
+ else
+ err = errno;
+ }
+
+ if (err)
+ FATAL_ERROR ((0, err, _("Cannot save working directory")));
+ }
+
+ if (curr->saved)
+ {
+ if (restore_cwd (&curr->saved_cwd))
+ FATAL_ERROR ((0, 0, _("Cannot change working directory")));
+ }
+ else
+ {
+ if (i && ! ISSLASH (curr->name[0]))
+ chdir_do (i - 1);
+ if (chdir (curr->name) != 0)
+ chdir_fatal (curr->name);
+ }
+
+ previous = i;
+ }
+}
+\f
+void
+close_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ close_warn (name);
+ else
+ close_error (name);
+}
+
+void
+open_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ open_warn (name);
+ else
+ open_error (name);
+}
+
+void
+read_diag_details (char const *name, off_t offset, size_t size)
+{
+ if (ignore_failed_read_option)
+ read_warn_details (name, offset, size);
+ else
+ read_error_details (name, offset, size);
+}
+
+void
+readlink_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ readlink_warn (name);
+ else
+ readlink_error (name);
+}
+
+void
+savedir_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ savedir_warn (name);
+ else
+ savedir_error (name);
+}
+
+void
+seek_diag_details (char const *name, off_t offset)
+{
+ if (ignore_failed_read_option)
+ seek_warn_details (name, offset);
+ else
+ seek_error_details (name, offset);
+}
+
+void
+stat_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ stat_warn (name);
+ else
+ stat_error (name);
+}
+
+void
+write_fatal_details (char const *name, ssize_t status, size_t size)
+{
+ write_error_details (name, status, size);
+ fatal_exit ();
+}
+
+/* Fork, aborting if unsuccessful. */
+pid_t
+xfork (void)
+{
+ pid_t p = fork ();
+ if (p == (pid_t) -1)
+ call_arg_fatal ("fork", _("child process"));
+ return p;
+}
+
+/* Create a pipe, aborting if unsuccessful. */
+void
+xpipe (int fd[2])
+{
+ if (pipe (fd) < 0)
+ call_arg_fatal ("pipe", _("interprocess channel"));
+}
+
+/* Return PTR, aligned upward to the next multiple of ALIGNMENT.
+ ALIGNMENT must be nonzero. The caller must arrange for ((char *)
+ PTR) through ((char *) PTR + ALIGNMENT - 1) to be addressable
+ locations. */
+
+static inline void *
+ptr_align (void *ptr, size_t alignment)
+{
+ char *p0 = ptr;
+ char *p1 = p0 + alignment - 1;
+ return p1 - (size_t) p1 % alignment;
+}
+
+/* Return the address of a page-aligned buffer of at least SIZE bytes.
+ The caller should free *PTR when done with the buffer. */
+
+void *
+page_aligned_alloc (void **ptr, size_t size)
+{
+ size_t alignment = getpagesize ();
+ size_t size1 = size + alignment;
+ if (size1 < size)
+ xalloc_die ();
+ *ptr = xmalloc (size1);
+ return ptr_align (*ptr, alignment);
+}