GEMini Atari/GEMini_Atari_CD-ROM_Walnut_Creek_December_1993.iso/files/gnu/mntlib16/getpw.c

C/C++ Source or Header | 1993-07-29 | 4.2 KB | 213 lines

/*
Subject:  v08i080:  Public-domain getpw*(3) routines
Newsgroups: mod.sources
Approved: mirror!rs

Submitted by: emoryu1!emoryu2!arnold (Arnold D. Robbins)
Mod.sources: Volume 8, Issue 80
Archive-name: getpw

Here is public domain re-implementation of the getpwent(3) routines. I have
not included a manual page, since every Unix system has one. I also haven't
even bothered to include a <pwd.h> file; you should be able to use the one
on your system.

There is one additional routine:
      setpwfile (file)
      char *file;
which will cause the routines to find password records from a file besides
/etc/passwd.  This is useful should you need to use saved password files,
for instance in doing Unix accounting, where you wish to keep info around on
old accounts, but take the old accounts out of the live password file.
(Can you guess why I just whipped these up?)

To switch files, call setpwfile as the very first thing, or call endpwent(),
then setpwfile ("/some/file").

Anyway, I hope this is useful to somene out there.
Arnold Robbins
arnold@emoryu1.{CSNET, UUCP, ARPA, BITNET}
*/

/* minorly customized by ERS for the MiNT library */

#include <stdio.h>
#include <pwd.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>

static char *pwdfile = "/etc/passwd";    /* default passwd file */

static FILE *fp = NULL;
static struct passwd curentry;        /* static data to return */

static int nextent __PROTO((void));

void setpwfile (cp)
char *cp;
{
    endpwent();
    if(cp) pwdfile = cp;
}

void setpwent ()
{
    if (fp)
        rewind (fp);
#ifdef atarist
    else if ((fp = fopen (pwdfile, "rt")) == NULL)
#else
    else if ((fp = fopen (pwdfile, "r")) == NULL)
#endif
    {
#ifdef VERBOSE
        fprintf (stderr,
            "setpwent: %s non-existant or unreadable.\n", pwdfile);
#endif
    }
}

void endpwent ()
{
    if (fp)
    {
        fclose (fp);
        fp = NULL;
    }
}

struct passwd *getpwent ()
{
    if (! fp ) {
        setpwent();
        if (! fp )
            return (NULL);
    }

    if (! nextent ())
        return (NULL);
    else
        return (& curentry);
}

struct passwd *getpwuid (uid)
register int uid;
{
    setpwent ();
    while (nextent ())
        if (curentry.pw_uid == uid)
            return (& curentry);

    return (NULL);
}

struct passwd *getpwnam (name)
register char *name;
{
    setpwent ();

    while (nextent ())
        if (strcmp (curentry.pw_name, name) == 0)
            return (& curentry);

    return (NULL);
}

#ifdef atarist
static char savbuf[256];    /* BUFSIZ seems bigger than necessary! */
#else
static char savbuf[BUFSIZ];
#endif

static int nextent ()
{
    register char *cp;

    if (! fp ) {
        setpwent ();
        if (! fp )
            return (0);
    }

    while (fgets (savbuf, sizeof(savbuf), fp) != NULL)
    {
        for (cp = savbuf; *cp && *cp != ':'; cp++)
            ;
        curentry.pw_name = savbuf;
        *cp++ = '\0';
        curentry.pw_passwd = cp;
        for (; *cp && *cp != ':'; cp++)
            ;
        *cp++ = '\0';
        curentry.pw_uid = atoi (cp);
        for (; *cp && *cp != ':'; cp++)
            ;
        *cp++ = '\0';
        curentry.pw_gid = atoi (cp);
        for (; *cp && *cp != ':'; cp++)
            ;
        *cp++ = '\0';
        curentry.pw_gecos = cp;
        for (; *cp && *cp != ':'; cp++)
            ;
        *cp++ = '\0';
        curentry.pw_dir = cp;
        for (; *cp && *cp != ':'; cp++)
            ;
        *cp++ = '\0';
        curentry.pw_shell = cp;
        for (; *cp && *cp != ':' && *cp != '\n'; cp++)
            ;
        *cp++ = '\0';
        return (1);
    }
    return (0);
}

#ifdef TEST
main (argc, argv)
int argc;
char **argv;
{
    struct passwd *pwd;

    if (argc > 1)
        setpwfile (argv[1]);

    setpwent ();
    while ((pwd = getpwent ()) != NULL)
    {
        printf ("%s:\n\t%s\n\t%d\n\t%d\n\t%s\n\t%s\n\t%s\n",
            pwd->pw_name,
            pwd->pw_passwd,
            pwd->pw_uid,
            pwd->pw_gid,
            pwd->pw_gecos,
            pwd->pw_dir,
            pwd->pw_shell);
    }
    endpwent ();

    if (pwd = getpwnam ("operator"))
        printf ("%s:\n\t%s\n\t%d\n\t%d\n\t%s\n\t%s\n\t%s\n",
            pwd->pw_name,
            pwd->pw_passwd,
            pwd->pw_uid,
            pwd->pw_gid,
            pwd->pw_gecos,
            pwd->pw_dir,
            pwd->pw_shell);

    if (pwd = getpwuid (1))
        printf ("%s:\n\t%s\n\t%d\n\t%d\n\t%s\n\t%s\n\t%s\n",
            pwd->pw_name,
            pwd->pw_passwd,
            pwd->pw_uid,
            pwd->pw_gid,
            pwd->pw_gecos,
            pwd->pw_dir,
            pwd->pw_shell);
}
#endif