Unix System Administration Handbook 1997 October/usah_oct97.iso/news/cnews.tar/libcnews/config.c

C/C++ Source or Header | 1994-08-17 | 4KB | 238 lines

/*
 * news configuration inquiry
 */

#include <stdio.h>
#include <sys/types.h>
#include "libc.h"
#include "news.h"
#include "config.h"

#ifndef NULL
#define    NULL    0
#endif

#ifndef NEWSCTL
/* =()<#define    NEWSCTL    "@<NEWSCTL>@">()= */
#define    NEWSCTL    "/etc/news"
#endif
#ifndef NEWSPATH
/* =()<#define    NEWSPATH    "@<NEWSPATH>@">()= */
#define    NEWSPATH    "/bin:/usr/bin:/usr/contrib/bin"
#endif
#ifndef NEWSARTS
/* =()<#define    NEWSARTS    "@<NEWSARTS>@">()= */
#define    NEWSARTS    "/var/news"
#endif
#ifndef NEWSBIN
/* =()<#define    NEWSBIN    "@<NEWSBIN>@">()= */
#define    NEWSBIN    "/usr/libexec/news"
#endif
#ifndef NEWSUMASK
/* =()<#define    NEWSUMASK    @<NEWSUMASK>@>()= */
#define    NEWSUMASK    022
#endif
#ifndef NEWSCONFIG
/* =()<#define    NEWSCONFIG    "@<NEWSCONFIG>@">()= */
#define    NEWSCONFIG    "/etc/news/bin/config"
#endif

static char *pwd = NULL;    /* Current directory, NULL means unknown. */
static int dirsset = NO;    /* Have the following been set up? */
static char *arts = NEWSARTS;
static char *bin = NEWSBIN;
static char *ctl = NEWSCTL;
static char *path = NEWSPATH;
static int numask = NEWSUMASK;
static char *nconfig = NEWSCONFIG;
#define    DIRS()    if (!dirsset) setdirs()

extern char *getenv();

/*
 - setdirs - set up stuff from environment, for use by other functions
 *
 * Invokes user-supplied function unprivileged() if non-standard values used.
 */
static void
setdirs()
{
    register char *p;
    register int mask;
    register char *scan;
    register int ns = 0;
#    define    NONSTD(reason)    { if (!ns) { unprivileged(reason); ns = 1; } }

    if (dirsset)
        return;

    p = getenv("NEWSARTS");
    if (p != NULL && !STREQ(p, arts)) {
        arts = p;
        NONSTD("NEWSARTS");
    }

    p = getenv("NEWSCTL");
    if (p != NULL && !STREQ(p, ctl)) {
        ctl = p;
        NONSTD("NEWSCTL");
    }

    p = getenv("NEWSPATH");
    if (p != NULL && !STREQ(p, path)) {
        path = p;
        NONSTD("NEWSPATH");
    }

    p = getenv("NEWSBIN");
    if (p != NULL && !STREQ(p, bin)) {
        bin = p;
        NONSTD("NEWSBIN");
    }

    p = getenv("NEWSUMASK");
    if (p != NULL) {
        mask = 0;
        for (scan = p; *scan != '\0'; scan++)
            if ('0' <= *scan && *scan <= '7' && mask <= 077)
                mask = (mask << 3) | (*scan - '0');
            else {    /* Garbage, ignore it. */
                mask = numask;
                break;            /* NOTE BREAK OUT */
            }
        if (mask != numask) {
            numask = mask;
            NONSTD("NEWSUMASK");
        }
    }

    p = getenv("NEWSCONFIG");
    if (p != NULL && !STREQ(p, nconfig)) {
        nconfig = p;
        NONSTD("NEWSCONFIG");
    }

    dirsset = YES;
}

/*
 - artfile - best pathname for a file in NEWSARTS
 */
char *
artfile(base)
char *base;
{
    static char *artf = NULL;

    DIRS();

    if (base == NULL)    /* he just wants the directory */
        return (arts);

    if (artf != NULL)
        free(artf);    /* toss old returned value */
    if (pwd != NULL && STREQ(pwd, arts))
        artf = strsave(base);
    else
        artf = str3save(arts, SFNDELIM, base);

    return (artf);
}

/*
 - fullartfile - full pathname for a file in NEWSARTS
 */
char *
fullartfile(base)
char *base;
{
    register char *p;
    register char *pwdsave;

    pwdsave = pwd;
    pwd = NULL;        /* fool artfile() into giving full path */
    p = artfile(base);
    pwd = pwdsave;
    return (p);
}

/*
 - ctlfile - full pathname for a file in NEWSCTL
 */
char *
ctlfile(base)
char *base;
{
    static char *ctlf = NULL;

    DIRS();

    if (ctlf != NULL)
        free(ctlf);        /* toss old returned value */

    if (base == NULL) {
        ctlf = NULL;
        return(ctl);
    } else {
        ctlf = str3save(ctl, SFNDELIM, base);
        return(ctlf);
    }
}

/*
 - binfile - full pathname for a file in NEWSBIN
 */
char *
binfile(base)
char *base;
{
    static char *binf = NULL;

    DIRS();

    if (binf != NULL)
        free(binf);        /* toss old returned value */

    if (base == NULL) {
        binf = NULL;
        return(bin);
    } else {
        binf = str3save(bin, SFNDELIM, base);
        return (binf);
    }
}

/*
 - cd - change to a directory, with checking
 */
void
cd(dir)
char *dir;
{
    if (pwd != NULL)
        free(pwd);
    if (chdir(dir) < 0)
        errunlock("cannot chdir(%s)", dir);
    pwd = strsave(dir);
}

/*
 - newspath - search path for normal system commands
 */
char *
newspath()
{
    DIRS();
    return(path);
}

/*
 - newsumask - suitable value of umask for news stuff
 */
int
newsumask()
{
    DIRS();
    return(numask);
}