backupfile.c rewrite to avoid arbitrary limits on lengths of

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.

0 files changed, 0 insertions, 0 deletions