4.3BSD-UWisc/src/lib/libc/gen/getgrent.c
#if defined(LIBC_RCS) && !defined(lint)
static char rcs_id[] =
"$Header: getgrent.c,v 1.3 86/09/08 14:42:55 tadl Exp $";
#endif
/*
* RCS info
* $Locker: $
*/
#ifndef lint
static char sccsid[] = "@(#)getgrent.c 1.1 86/02/03 Copyr 1984 Sun Micro";
#endif
/*
* Copyright (c) 1984 by Sun Microsystems, Inc.
* @(#)getgrent.c 2.2 86/04/14 NFSSRC
*/
#include <stdio.h>
#include <grp.h>
#include <rpcsvc/ypclnt.h>
#define MAXINT 0x7fffffff;
#define MAXGRP 200
static char domain[256];
static struct group NULLGP = {NULL, NULL, 0, NULL};
static char GROUP[] = "/etc/group";
static FILE *grf = NULL; /* pointer into /etc/group */
static char *yp; /* pointer into yellow pages */
static int yplen;
static char *oldyp = NULL;
static int oldyplen;
static struct group group;
static char *gr_mem[MAXGRP];
static struct list {
char *name;
struct list *nxt
} *minuslist; /* list of - items */
static struct group *interpret();
static struct group *interpretwithsave();
static struct group *save();
static struct group *getnamefromyellow();
static struct group *getgidfromyellow();
struct group *
getgrgid(gid)
register gid;
{
struct group *gp;
char line[BUFSIZ+1];
setgrent();
if (!grf)
return NULL;
while (fgets(line, BUFSIZ, grf) != NULL) {
gp = interpret(line, strlen(line));
if (matchgid(line, &gp, gid)) {
endgrent();
return gp;
}
}
endgrent();
return NULL;
}
struct group *
getgrnam(name)
register char *name;
{
struct group *gp;
char line[BUFSIZ+1];
setgrent();
if (!grf)
return NULL;
while (fgets(line, BUFSIZ, grf) != NULL) {
gp = interpret(line, strlen(line));
if (matchname(line, &gp, name)) {
endgrent();
return gp;
}
}
endgrent();
return NULL;
}
setgrent()
{
if (getdomainname(domain, sizeof(domain)) < 0) {
fprintf(stderr,
"setgrent: getdomainname system call missing\n");
exit(1);
}
if(!grf)
grf = fopen(GROUP, "r");
else
rewind(grf);
if (yp)
free(yp);
yp = NULL;
freeminuslist();
}
endgrent()
{
if(grf) {
fclose(grf);
grf = NULL;
}
if (yp)
free(yp);
yp = NULL;
freeminuslist();
}
static char *
grskip(p,c)
register char *p;
register c;
{
while(*p && *p != c && *p != '\n') ++p;
if(*p) *p++ = 0;
return(p);
}
struct group *
getgrent()
{
char line1[BUFSIZ+1];
register char *p, **q;
static struct group *savegp, *gp;
if (domain[0] == 0 && getdomainname(domain, sizeof(domain)) < 0) {
fprintf(stderr,
"getgrent: getdomainname system call missing\n");
exit(1);
}
if(!grf && !(grf = fopen(GROUP, "r")))
return(NULL);
again:
if (yp) {
gp = interpretwithsave(yp, yplen, savegp);
free(yp);
getnextfromyellow();
if (onminuslist(gp))
goto again;
else
return gp;
}
else if (!(p = fgets(line1, BUFSIZ, grf)))
return(NULL);
gp = interpret(line1, strlen(line1));
switch(line1[0]) {
case '+':
if (strcmp(gp->gr_name, "+") == 0) {
getfirstfromyellow();
savegp = save(gp);
goto again;
}
savegp = save(gp);
gp = getnamefromyellow(gp->gr_name+1, savegp);
if (gp == NULL)
goto again;
else if (onminuslist(gp))
goto again;
else
return gp;
break;
case '-':
addtominuslist(gp->gr_name+1);
goto again;
break;
default:
if (onminuslist(gp))
goto again;
return gp;
break;
}
}
static struct group *
interpret(val, len)
char *val;
{
register char *p, **q;
static struct group gp;
static char line[BUFSIZ+1];
strncpy(line, val, len);
p = line;
line[len] = '\n';
line[len+1] = 0;
gp.gr_name = p;
gp.gr_passwd = p = grskip(p,':');
gp.gr_gid = atoi(p = grskip(p,':'));
gp.gr_mem = gr_mem;
p = grskip(p,':');
grskip(p,'\n');
q = gr_mem;
while(*p){
if (q < &gr_mem[MAXGRP-1])
*q++ = p;
p = grskip(p,',');
}
*q = NULL;
return(&gp);
}
static
freeminuslist() {
struct list *ls;
for (ls = minuslist; ls != NULL; ls = ls->nxt) {
free(ls->name);
free(ls);
}
minuslist = NULL;
}
static struct group *
interpretwithsave(val, len, savegp)
char *val;
struct group *savegp;
{
struct group *gp;
gp = interpret(val, len);
if (savegp->gr_passwd && *savegp->gr_passwd)
gp->gr_passwd = savegp->gr_passwd;
if (savegp->gr_mem && *savegp->gr_mem)
gp->gr_mem = savegp->gr_mem;
return gp;
}
static
onminuslist(gp)
struct group *gp;
{
struct list *ls;
register char *nm;
nm = gp->gr_name;
for (ls = minuslist; ls != NULL; ls = ls->nxt)
if (strcmp(ls->name, nm) == 0)
return 1;
return 0;
}
static
getnextfromyellow()
{
int reason;
char *key;
int keylen;
if (reason = yp_next(domain, "group.byname",
oldyp, oldyplen, &key, &keylen,
&yp, &yplen)) {
#ifdef DEBUG
fprintf(stderr, "reason yp_next failed is %d\n", reason);
#endif
yp = NULL;
}
if (oldyp)
free(oldyp);
oldyp = key;
oldyplen = keylen;
}
static
getfirstfromyellow()
{
int reason;
char *key;
int keylen;
if (reason = yp_first(domain, "group.byname",
&key, &keylen, &yp, &yplen)) {
#ifdef DEBUG
fprintf(stderr, "reason yp_first failed is %d\n", reason);
#endif
yp = NULL;
}
if (oldyp)
free(oldyp);
oldyp = key;
oldyplen = keylen;
}
static struct group *
getnamefromyellow(name, savegp)
char *name;
struct group *savegp;
{
struct group *gp;
int reason;
char *val;
int vallen;
if (reason = yp_match(domain, "group.byname",
name, strlen(name), &val, &vallen)) {
#ifdef DEBUG
fprintf(stderr, "reason yp_next failed is %d\n", reason);
#endif
return NULL;
}
else {
gp = interpret(val, vallen);
free(val);
if (savegp->gr_passwd && *savegp->gr_passwd)
gp->gr_passwd = savegp->gr_passwd;
if (savegp->gr_mem && *savegp->gr_mem)
gp->gr_mem = savegp->gr_mem;
return gp;
}
}
static
addtominuslist(name)
char *name;
{
struct list *ls;
char *buf;
ls = (struct list *)malloc(sizeof(struct list));
buf = (char *)malloc(strlen(name) + 1);
strcpy(buf, name);
ls->name = buf;
ls->nxt = minuslist;
minuslist = ls;
}
/*
* save away psswd, gr_mem fields, which are the only
* ones which can be specified in a local + entry to override the
* value in the yellow pages
*/
static struct group *
save(gp)
struct group *gp;
{
static struct group *sv;
char *gr_mem[MAXGRP];
char **av, **q;
int lnth;
/*
* free up stuff from last time around
*/
if (sv) {
for (av = sv->gr_mem; *av != NULL; av++) {
if (q >= &gr_mem[MAXGRP-1])
break;
free(*q);
q++;
}
free(sv->gr_passwd);
free(sv->gr_mem);
free(sv);
}
sv = (struct group *)malloc(sizeof(struct group));
sv->gr_passwd = (char *)malloc(strlen(gp->gr_passwd) + 1);
strcpy(sv->gr_passwd, gp->gr_passwd);
q = gr_mem;
for (av = gp->gr_mem; *av != NULL; av++) {
if (q >= &gr_mem[MAXGRP-1])
break;
*q = (char *)malloc(strlen(*av) + 1);
strcpy(*q, *av);
q++;
}
*q = 0;
lnth = (sizeof (char *)) * (q - gr_mem + 1);
sv->gr_mem = (char **)malloc(lnth);
bcopy(gr_mem, sv->gr_mem, lnth);
return sv;
}
static
matchname(line1, gpp, name)
char line1[];
struct group **gpp;
char *name;
{
struct group *savegp;
struct group *gp = *gpp;
switch(line1[0]) {
case '+':
if (strcmp(gp->gr_name, "+") == 0) {
savegp = save(gp);
gp = getnamefromyellow(name, savegp);
if (gp) {
*gpp = gp;
return 1;
}
else
return 0;
}
if (strcmp(gp->gr_name+1, name) == 0) {
savegp = save(gp);
gp = getnamefromyellow(gp->gr_name+1, savegp);
if (gp) {
*gpp = gp;
return 1;
}
else
return 0;
}
break;
case '-':
if (strcmp(gp->gr_name+1, name) == 0) {
*gpp = NULL;
return 1;
}
break;
default:
if (strcmp(gp->gr_name, name) == 0)
return 1;
}
return 0;
}
static
matchgid(line1, gpp, gid)
char line1[];
struct group **gpp;
{
struct group *savegp;
struct group *gp = *gpp;
switch(line1[0]) {
case '+':
if (strcmp(gp->gr_name, "+") == 0) {
savegp = save(gp);
gp = getgidfromyellow(gid, savegp);
if (gp) {
*gpp = gp;
return 1;
}
else
return 0;
}
savegp = save(gp);
gp = getnamefromyellow(gp->gr_name+1, savegp);
if (gp && gp->gr_gid == gid) {
*gpp = gp;
return 1;
}
else
return 0;
break;
case '-':
if (gid == gidof(gp->gr_name+1)) {
*gpp = NULL;
return 1;
}
break;
default:
if (gp->gr_gid == gid)
return 1;
}
return 0;
}
static
gidof(name)
char *name;
{
struct group *gp;
gp = getnamefromyellow(name, &NULLGP);
if (gp)
return gp->gr_gid;
else
return MAXINT;
}
static struct group *
getgidfromyellow(gid, savegp)
int gid;
struct group *savegp;
{
struct group *gp;
int reason;
char *val;
int vallen;
char gidstr[20];
sprintf(gidstr, "%d", gid);
if (reason = yp_match(domain, "group.bygid",
gidstr, strlen(gidstr), &val, &vallen)) {
#ifdef DEBUG
fprintf(stderr, "reason yp_next failed is %d\n", reason);
#endif
return NULL;
}
else {
gp = interpret(val, vallen);
free(val);
if (savegp->gr_passwd && *savegp->gr_passwd)
gp->gr_passwd = savegp->gr_passwd;
if (savegp->gr_mem && *savegp->gr_mem)
gp->gr_mem = savegp->gr_mem;
return gp;
}
}