numeric backup extensions.
Include "backupfile.h" first.
Include errno.h, stdbool.h, limits.h, unistd.h, xalloc.h.
(CLOSEDIR, INT_STRLEN_BOUND): Remove.
(pathconf) [! (HAVE_PATHCONF && defined _PC_NAME_MAX)]: New macro.
(_POSIX_NAME_MAX) [!defined _POSIX_NAME_MAX]: New macro.
(NAME_MAX_MAXIMUM): New macro. Unlike the old addext.c, we
also look at _XOPEN_NAME_MAX, for better performance on modern
hosts that support only file names of length 255 or more.
(ISDIGIT): unsigned -> unsigned int
(max_backup_version, version_number): Remove.
(check_extension): New function. Similar to the old addext, but
static, assumes that the extension has already been added,
and a bit more careful on DOS hosts.
(numbered_backup): New function. It does what max_backup_version
and version_number used to do, but it doesn't use integer arithmetic
to calculate extensions so it doesn't overflow.
(find_backup_file_name): Rewrite to use these new functions.
This has a new optimization: we needn't call pathconf if the
new numbered backup name has the same length as the old.
Also, use xmalloc rather than malloc, so that the caller
needn't worry about memory exhaustion.
(S_IXUSR, S_IXGRP, S_IXOTH, S_IROTH, S_IWOTH, S_IXOTH):
Remove; now done by stat-macros.h.
(NGROUPS_MAX, group_member): Remove; now down by group-member.h.
No need to include <limits.h>.
(errno): Remove decl; we now assume C89 or better.
(access, getuid, getgid, geteuid, getegid, stat) [defined _LIBC]:
New macros.
(uid, gid, have_ids): Remove these static variables.
They weren't accurate for programs that also invoked setreuid etc.
(euidaccess) [defined EFF_ONLY_OK || defined ACC_SELF ||
HAVE_DECL_EACCSS]: Use builtin substitutes.
[defined _LIBC]: Ignore __libc_enable_secure; it's not a
correct optimization for programs run as root that later
invoke setreuid.
[no builtin substitutes && HAVE_DECL_SETREGID &&
PREFER_NONREENTRANT_EUIDACCESS]:
Use setreuid+setregid to get the correct answer.
[no builtin substitutes && ! (HAVE_DECL_SETREGID &&
PREFER_NONREENTRANT_EUIDACCESS)]:
Don't assume that the stat macros have their historical values,
as POSIX doesn't require this.
[defined TEST]: Include <stdlib.h>; don't include errno.h
twice; include <error.h> rather than "error.h".
if HAVE_GETLOADAVG is defined, so that the test program can work.
(errno): Remove declaration; not needed in C89 or later.
Include "c-strtod.h".
Do not include locale.h or define setlocale; no longer needed.
Include <limits.h>.
(INT_STRLEN_BOUND): New macro.
(getloadavg): Use it to compute buffer size.
Don't assume that buffer will be properly terminated by 'read'.
Use c_strtod instead of setlocale.
(main) [defined TEST]: Return int, not void.
Detect symlink loops much earlier (albeit lazily) on systems
with MAXSYMLINKS defined to a large value.
Include "cycle-check.h".
(canonicalize_filename_mode): Don't try to detect loops by counting
symlink-hops. Instead, use the cycle-check module.
(canonicalize_filename_mode): New function, based on
canonicalize_file_name, supports three canonicalize modes.
(canonicalize_file_name)
[!HAVE_CANONICALIZE_FILE_NAME && !HAVE_RESOLVEPATH]: Use it.
Don't include stdio.h, stdlib.h, unistd.h, strdup.h.
(longest_relative_suffix): New function.
(path_concat): Use it. Assume first argument is not NULL.
Port to DOS. Omit redundant separators.
Report an error instead of returning NULL.
Use mempcpy instead of memcpy.
(xpath_concat): Remove: not declared or used.
Paul Eggert