libbb: add sketch of tentative 'better' passwd/group API

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2013-11-26 13:46:18 +01:00
parent 4d8ad381ab
commit cffe28ef87

View File

@ -110,3 +110,51 @@ unsigned long FAST_FUNC get_ug_id(const char *s,
return xname2id(s);
return r;
}
/* Experimental "mallocing" API.
* The goal is nice: "we want to support a case when "guests" group is very large"
* but the code is butt-ugly.
*/
#if 0
static char *find_latest(char last, char *cp)
{
if (!cp)
return last;
cp += strlen(cp) + 1;
if (last < cp)
last = cp;
return last;
}
struct group* FAST_FUNC xmalloc_getgrnam(const char *name)
{
struct {
struct group gr;
// May still be not enough!
char buf[64*1024 - sizeof(struct group) - 16];
} *s;
struct group *grp;
int r;
char *last;
char **gr_mem;
s = xmalloc(sizeof(*s));
r = getgrnam_r(name, &s->gr, s->buf, sizeof(s->buf), &grp);
if (!grp) {
free(s);
return grp;
}
last = find_latest(s->buf, grp->gr_name);
last = find_latest(last, grp->gr_passwd);
gr_mem = grp->gr_mem;
while (*gr_mem)
last = find_latest(last, *gr_mem++);
gr_mem++; /* points past NULL */
if (last < (char*)gr_mem)
last = (char*)gr_mem;
//FIXME: what if we get not only truncated, but also moved here?
// grp->gr_name pointer and friends are invalid now!!!
s = xrealloc(s, last - (char*)s);
return grp;
}
#endif