/* userspec.c -- Parse a user and group string.
- Copyright (C) 1989-1992, 1997-1998, 2000, 2002-2010 Free Software
+ Copyright (C) 1989-1992, 1997-1998, 2000, 2002-2013 Free Software
Foundation, Inc.
This program is free software: you can redistribute it and/or modify
- It's typically faster.
POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to
isdigit unless it's important to use the locale's definition
- of `digit' even when the host does not conform to POSIX. */
-#define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
+ of "digit" even when the host does not conform to POSIX. */
+# define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
/* Return true if STR represents an unsigned decimal integer. */
char const *g;
char *gname = NULL;
uid_t unum = *uid;
- gid_t gnum = *gid;
+ gid_t gnum = gid ? *gid : -1;
error_msg = NULL;
- *username = *groupname = NULL;
+ if (username)
+ *username = NULL;
+ if (groupname)
+ *groupname = NULL;
/* Set U and G to nonzero length strings corresponding to user and
group specifiers or to NULL. If U is not NULL, it is a newly
#ifdef __DJGPP__
/* Pretend that we are the user U whose group is G. This makes
- pwd and grp functions ``know'' about the UID and GID of these. */
+ pwd and grp functions "know" about the UID and GID of these. */
if (u && !is_number (u))
setenv ("USER", u, 1);
if (g && !is_number (g))
if (error_msg == NULL)
{
*uid = unum;
- *gid = gnum;
- *username = u;
- *groupname = gname;
- u = NULL;
+ if (gid)
+ *gid = gnum;
+ if (username)
+ {
+ *username = u;
+ u = NULL;
+ }
+ if (groupname)
+ {
+ *groupname = gname;
+ gname = NULL;
+ }
}
- else
- free (gname);
free (u);
+ free (gname);
return _(error_msg);
}
/* Extract from SPEC, which has the form "[user][:.][group]",
a USERNAME, UID U, GROUPNAME, and GID G.
+ If the GID parameter is NULL the entire SPEC is treated as a user.
+ If the USERNAME and GROUPNAME parameters are NULL they're ignored.
Either user or group, or both, must be present.
If the group is omitted but the separator is given,
use the given user's login group.
- If SPEC contains a `:', then use that as the separator, ignoring
- any `.'s. If there is no `:', but there is a `.', then first look
+ If SPEC contains a ':', then use that as the separator, ignoring
+ any '.'s. If there is no ':', but there is a '.', then first look
up the entire SPEC as a login name. If that look-up fails, then
- try again interpreting the `.' as a separator.
+ try again interpreting the '.' as a separator.
USERNAME and GROUPNAME will be in newly malloc'd memory.
Either one might be NULL instead, indicating that it was not
parse_user_spec (char const *spec, uid_t *uid, gid_t *gid,
char **username, char **groupname)
{
- char const *colon = strchr (spec, ':');
+ char const *colon = gid ? strchr (spec, ':') : NULL;
char const *error_msg =
parse_with_separator (spec, colon, uid, gid, username, groupname);
- if (!colon && error_msg)
+ if (gid && !colon && error_msg)
{
/* If there's no colon but there is a dot, and if looking up the
- whole spec failed (i.e., the spec is not a owner name that
+ whole spec failed (i.e., the spec is not an owner name that
includes a dot), then try again, but interpret the dot as a
separator. This is a compatible extension to POSIX, since
the POSIX-required behavior is always tried first. */