From cffe28ef876a6fe8a8154321bf5feb409d87cf1a Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Tue, 26 Nov 2013 13:46:18 +0100 Subject: [PATCH] libbb: add sketch of tentative 'better' passwd/group API Signed-off-by: Denys Vlasenko --- libbb/bb_pwd.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/libbb/bb_pwd.c b/libbb/bb_pwd.c index 4829b723a..8250cd446 100644 --- a/libbb/bb_pwd.c +++ b/libbb/bb_pwd.c @@ -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 -- 2.25.1