+
+ /* 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)
+ {
+ prev->saved = 1;
+ if (save_cwd (&prev->saved_cwd) != 0)
+ FATAL_ERROR ((0, 0, _("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
+/* Decode MODE from its binary form in a stat structure, and encode it
+ into a 9-byte string STRING, terminated with a NUL. */
+
+void
+decode_mode (mode_t mode, char *string)
+{
+ *string++ = mode & S_IRUSR ? 'r' : '-';
+ *string++ = mode & S_IWUSR ? 'w' : '-';
+ *string++ = (mode & S_ISUID
+ ? (mode & S_IXUSR ? 's' : 'S')
+ : (mode & S_IXUSR ? 'x' : '-'));
+ *string++ = mode & S_IRGRP ? 'r' : '-';
+ *string++ = mode & S_IWGRP ? 'w' : '-';
+ *string++ = (mode & S_ISGID
+ ? (mode & S_IXGRP ? 's' : 'S')
+ : (mode & S_IXGRP ? 'x' : '-'));
+ *string++ = mode & S_IROTH ? 'r' : '-';
+ *string++ = mode & S_IWOTH ? 'w' : '-';
+ *string++ = (mode & S_ISVTX
+ ? (mode & S_IXOTH ? 't' : 'T')
+ : (mode & S_IXOTH ? 'x' : '-'));
+ *string = '\0';
+}
+
+/* Report an error associated with the system call CALL and the
+ optional name NAME. */
+static void
+call_arg_error (char const *call, char const *name)
+{
+ int e = errno;
+ ERROR ((0, e, _("%s: Cannot %s"), quotearg_colon (name), call));
+}
+
+/* Report a fatal error associated with the system call CALL and
+ the optional file name NAME. */
+static void
+call_arg_fatal (char const *call, char const *name)
+{
+ int e = errno;
+ FATAL_ERROR ((0, e, _("%s: Cannot %s"), quotearg_colon (name), call));
+}
+
+/* Report a warning associated with the system call CALL and
+ the optional file name NAME. */
+static void
+call_arg_warn (char const *call, char const *name)
+{
+ int e = errno;
+ WARN ((0, e, _("%s: Warning: Cannot %s"), quotearg_colon (name), call));
+}
+
+void
+chdir_fatal (char const *name)
+{
+ call_arg_fatal ("chdir", name);
+}
+
+void
+chmod_error_details (char const *name, mode_t mode)
+{
+ int e = errno;
+ char buf[10];
+ decode_mode (mode, buf);
+ ERROR ((0, e, _("%s: Cannot change mode to %s"),
+ quotearg_colon (name), buf));
+}
+
+void
+chown_error_details (char const *name, uid_t uid, gid_t gid)
+{
+ int e = errno;
+ ERROR ((0, e, _("%s: Cannot change ownership to uid %lu, gid %lu"),
+ quotearg_colon (name), (unsigned long) uid, (unsigned long) gid));
+}
+
+void
+close_error (char const *name)
+{
+ call_arg_error ("close", name);
+}
+
+void
+close_warn (char const *name)
+{
+ call_arg_warn ("close", name);
+}
+
+void
+close_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ close_warn (name);
+ else
+ close_error (name);
+}
+
+void
+exec_fatal (char const *name)
+{
+ call_arg_fatal ("exec", name);
+}
+
+void
+link_error (char const *target, char const *source)
+{
+ int e = errno;
+ ERROR ((0, e, _("%s: Cannot hard link to %s"),
+ quotearg_colon (source), quote_n (1, target)));
+}
+
+void
+mkdir_error (char const *name)
+{
+ call_arg_error ("mkdir", name);
+}
+
+void
+mkfifo_error (char const *name)
+{
+ call_arg_error ("mkfifo", name);
+}
+
+void
+mknod_error (char const *name)
+{
+ call_arg_error ("mknod", name);
+}
+
+void
+open_error (char const *name)
+{
+ call_arg_error ("open", name);
+}
+
+void
+open_fatal (char const *name)
+{
+ call_arg_fatal ("open", name);
+}
+
+void
+open_warn (char const *name)
+{
+ call_arg_warn ("open", name);
+}
+
+void
+open_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ open_warn (name);
+ else
+ open_error (name);
+}
+
+void
+read_error (char const *name)
+{
+ call_arg_error ("read", name);
+}
+
+void
+read_error_details (char const *name, off_t offset, size_t size)
+{
+ char buf[UINTMAX_STRSIZE_BOUND];
+ int e = errno;
+ ERROR ((0, e,
+ ngettext ("%s: Read error at byte %s, reading %lu byte",
+ "%s: Read error at byte %s, reading %lu bytes",
+ size),
+ quotearg_colon (name), STRINGIFY_BIGINT (offset, buf),
+ (unsigned long) size));
+}
+
+void
+read_warn_details (char const *name, off_t offset, size_t size)
+{
+ char buf[UINTMAX_STRSIZE_BOUND];
+ int e = errno;
+ WARN ((0, e,
+ ngettext ("%s: Warning: Read error at byte %s, reading %lu byte",
+ "%s: Warning: Read error at byte %s, reading %lu bytes",
+ size),
+ quotearg_colon (name), STRINGIFY_BIGINT (offset, buf),
+ (unsigned long) size));
+}
+
+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
+read_fatal (char const *name)
+{
+ call_arg_fatal ("read", name);
+}
+
+void
+read_fatal_details (char const *name, off_t offset, size_t size)
+{
+ char buf[UINTMAX_STRSIZE_BOUND];
+ int e = errno;
+ FATAL_ERROR ((0, e,
+ ngettext ("%s: Read error at byte %s, reading %lu byte",
+ "%s: Read error at byte %s, reading %lu bytes",
+ size),
+ quotearg_colon (name), STRINGIFY_BIGINT (offset, buf),
+ (unsigned long) size));
+}
+
+void
+readlink_error (char const *name)
+{
+ call_arg_error ("readlink", name);
+}
+
+void
+readlink_warn (char const *name)
+{
+ call_arg_warn ("readlink", name);
+}
+
+void
+readlink_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ readlink_warn (name);
+ else
+ readlink_error (name);
+}
+
+void
+savedir_error (char const *name)
+{
+ call_arg_error ("savedir", name);
+}
+
+void
+savedir_warn (char const *name)
+{
+ call_arg_warn ("savedir", name);
+}
+
+void
+savedir_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ savedir_warn (name);
+ else
+ savedir_error (name);
+}
+
+void
+seek_error (char const *name)
+{
+ call_arg_error ("seek", name);
+}
+
+void
+seek_error_details (char const *name, off_t offset)
+{
+ char buf[UINTMAX_STRSIZE_BOUND];
+ int e = errno;
+ ERROR ((0, e, _("%s: Cannot seek to %s"),
+ quotearg_colon (name),
+ STRINGIFY_BIGINT (offset, buf)));
+}
+
+void
+seek_warn (char const *name)
+{
+ call_arg_warn ("seek", name);
+}
+
+void
+seek_warn_details (char const *name, off_t offset)
+{
+ char buf[UINTMAX_STRSIZE_BOUND];
+ int e = errno;
+ WARN ((0, e, _("%s: Warning: Cannot seek to %s"),
+ quotearg_colon (name),
+ STRINGIFY_BIGINT (offset, buf)));
+}
+
+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
+symlink_error (char const *contents, char const *name)
+{
+ int e = errno;
+ ERROR ((0, e, _("%s: Cannot create symlink to %s"),
+ quotearg_colon (name), quote_n (1, contents)));
+}
+
+void
+stat_error (char const *name)
+{
+ call_arg_error ("stat", name);
+}
+
+void
+stat_warn (char const *name)
+{
+ call_arg_warn ("stat", name);
+}
+
+void
+stat_diag (char const *name)
+{
+ if (ignore_failed_read_option)
+ stat_warn (name);
+ else
+ stat_error (name);
+}
+
+void
+truncate_error (char const *name)
+{
+ call_arg_error ("truncate", name);
+}
+
+void
+truncate_warn (char const *name)
+{
+ call_arg_warn ("truncate", name);
+}
+
+void
+unlink_error (char const *name)
+{
+ call_arg_error ("unlink", name);
+}
+
+void
+utime_error (char const *name)
+{
+ call_arg_error ("utime", name);
+}
+
+void
+waitpid_error (char const *name)
+{
+ call_arg_error ("waitpid", name);
+}
+
+void
+write_error (char const *name)
+{
+ call_arg_error ("write", name);
+}
+
+void
+write_error_details (char const *name, size_t status, size_t size)
+{
+ if (status == 0)
+ write_error (name);
+ else
+ ERROR ((0, 0,
+ ngettext ("%s: Wrote only %lu of %lu byte",
+ "%s: Wrote only %lu of %lu bytes",
+ size),
+ name, (unsigned long int) status, (unsigned long int) size));
+}
+
+void
+write_fatal (char const *name)
+{
+ call_arg_fatal ("write", 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);