common/string/strgid.c

/***********************************************************************
*                                                                      *
*               This software is part of the ast package               *
*          Copyright (c) 1985-2010 AT&T Intellectual Property          *
*                      and is licensed under the                       *
*                  Common Public License, Version 1.0                  *
*                    by AT&T Intellectual Property                     *
*                                                                      *
*                A copy of the License is available at                 *
*            http://www.opensource.org/licenses/cpl1.0.txt             *
*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
*                                                                      *
*              Information and Software Systems Research               *
*                            AT&T Research                             *
*                           Florham Park NJ                            *
*                                                                      *
*                 Glenn Fowler <gsf@research.att.com>                  *
*                  David Korn <dgk@research.att.com>                   *
*                   Phong Vo <kpv@research.att.com>                    *
*                                                                      *
***********************************************************************/
#pragma prototyped
/*
 * Glenn Fowler
 * AT&T Bell Laboratories
 *
 * gid name -> number
 */

#if defined(__STDPP__directive) && defined(__STDPP__hide)
__STDPP__directive pragma pp:hide getgrgid getgrnam getpwnam
#else
#define getgrgid    ______getgrgid
#define getgrnam    ______getgrnam
#define getpwnam    ______getpwnam
#endif

#include <ast.h>
#include <cdt.h>
#include <pwd.h>
#include <grp.h>

#if defined(__STDPP__directive) && defined(__STDPP__hide)
__STDPP__directive pragma pp:nohide getgrgid getgrnam getpwnam
#else
#undef  getgrgid
#undef  getgrnam
#undef  getpwnam
#endif

extern struct group*    getgrgid(gid_t);
extern struct group*    getgrnam(const char*);
extern struct passwd*   getpwnam(const char*);

typedef struct Id_s
{
    Dtlink_t    link;
    int     id;
    char        name[1];
} Id_t;

/*
 * return gid number given gid/uid name
 * gid attempted first, then uid->pw_gid
 * -1 on first error for a given name
 * -2 on subsequent errors for a given name
 */

int
strgid(const char* name)
{
    register Id_t*      ip;
    register struct group*  gr;
    register struct passwd* pw;
    int         id;
    char*           e;

    static Dt_t*        dict;
    static Dtdisc_t     disc;

    if (!dict)
    {
        disc.key = offsetof(Id_t, name);
        dict = dtopen(&disc, Dthash);
    }
    else if (ip = (Id_t*)dtmatch(dict, name))
        return ip->id;
    if (gr = getgrnam(name))
        id = gr->gr_gid;
    else if (pw = getpwnam(name))
        id = pw->pw_gid;
    else
    {
        id = strtol(name, &e, 0);
#if _WINIX
        if (!*e)
        {
            if (!getgrgid(id))
                id = -1;
        }
        else if (!streq(name, "sys"))
            id = -1;
        else if (gr = getgrnam("Administrators"))
            id = gr->gr_gid;
        else if (pw = getpwnam("Administrator"))
            id = pw->pw_gid;
        else
            id = -1;
#else
        if (*e || !getgrgid(id))
            id = -1;
#endif
    }
    if (dict && (ip = newof(0, Id_t, 1, strlen(name))))
    {
        strcpy(ip->name, name);
        ip->id = id >= 0 ? id : -2;
        dtinsert(dict, ip);
    }
    return id;
}