The Fatted Calf/The Fatted Calf.iso/Unix/CNews/Source/explode/trbatch.c

C/C++ Source or Header | 1992-04-18 | 4.9 KB | 219 lines

/*
 * transmit batch file management (exploder version)
 */
#include <stdio.h>
#include <sys/types.h>
#include "hdbm.h"
#include "hash.h"
#include "libc.h"
#include "news.h"
/* tunable parameter */
#ifndef NOPENBFS
#define NOPENBFS 250    /* # batchfiles kept open for batching */
#endif            /* NOPENBFS */
#include "trbatch.h"

/* tunable parameters */
#ifndef HASHFILSZ
#define HASHFILSZ (NOPENBFS/2)
            /* # of hash buckets for batch file names */
#endif            /* HASHFILSZ */

static HASHTABLE *nmbftbl;        /* name -> batchfile mapping */

/*
 * open "name" for appending.
 *
 * see if any batchfile has been assigned to "name" yet.
 * if an attempt to open the batchfile's stream fails, close an arbitrary
 * batchfile stream and retry the open.
 */
struct batchfile *
bfopen(name)
register char *name;
{
    register struct batchfile *bf;

    /* malloc_debug(0); */                /* DEBUG */
    bf = bfincache(name);
    if (bf->bf_str == NULL) {
        bf->bf_str = fopenclex(name, "a");    /* silent try */
        if (bf->bf_str == NULL) {
            if (bfrclose() != ST_OKAY)
                return NULL;
            errno = 0;
            warning(
    "had to close a descriptor to reuse it; this should not happen!\n",
                 "");
            /* retry, may bitch */
            bf->bf_str = fopenwclex(name, "a");
        }
        if (bf->bf_str != NULL)
            bfsetup(bf);
    }
    if (bf->bf_str == NULL)
        error("can't open %s", name);
    return bf;
}

/*
 * returns a batchfile, never NULL, corresponding to name.
 */
struct batchfile *
bfincache(name)
char *name;
{
    register struct batchfile *bf;

    bf = bfisopen(name);
    if (bf == NULL) {
        hfinstall(name);
        bf = bfisopen(name);
        if (bf == NULL)
            abort();    /* DEBUG */
    }
    return bf;
}

/*
 * write filename, message-id or size on batch file "bf".
 * under the 'f' flag, include the size in bytes of the article
 * after "name" to assist the C news batcher.  under the 'n' flag,
 * write the article's message-id.  afterward, flush "bf" in case
 * the machine crashes before the stream is closed.
 * don't check putc return value for portability; use ferror.
 */
int                            /* boolean */
bfappend(bf, flag, batname, artname, msgid, size)
register struct batchfile *bf;
int flag;
char *batname, *artname, *msgid;
long size;
{
    register FILE *bfstr = bf->bf_str;

    if (flag == 'I')
        artname = msgid;            /* cheat */
    if (fputs(artname, bfstr) == EOF)
        return NO;
    if (flag == 'f' && fprintf(bfstr, " %ld", size) == EOF)
        return NO;
    if (flag == 'n') {
        (void) putc(' ', bfstr);
        if (ferror(bfstr) || fputs(msgid, bfstr) == EOF)
            return NO;
    }
    (void) putc('\n', bfstr);
    if (ferror(bfstr) || bfflush(bf) == EOF)
        return NO;
    return YES;
}

/* --- hashing --- */

struct closehook {
    short    closedone;
    statust    status;
};

STATIC int
closefirst(key, data, hook)
HASHDATUM key, data;
char *hook;
{
    register struct closehook *chp = (struct closehook *)hook;
    register struct batchfile *bf;

    if (chp->closedone)
        return;
    bf = (struct batchfile *)data;
    if (bf->bf_str == NULL)
        return;
    chp->status = bfclose(bf);
    chp->closedone = YES;
}

STATIC statust
bfrclose()                /* close an arbitrary batchfile */
{
    struct closehook closehook;
    register struct closehook *chp = &closehook;

    chp->closedone = NO;
    chp->status = ST_OKAY;
    if (nmbftbl == NULL)
        return chp->status;
    hashwalk(nmbftbl, closefirst, (char *)chp);
    if (!chp->closedone) {
        errno = 0;
        warning("bfrclose couldn't find an open descriptor to close",
            "");
    }
    return chp->status;
}

STATIC int
closeone(key, data, hook)        /* close a given open batch file */
HASHDATUM key, data;
char *hook;
{
    register struct closehook *chp = (struct closehook *)hook;
    register struct batchfile *bf = (struct batchfile *)data;

    if (bf->bf_str != NULL)        /* batch file stream open */
        chp->status |= bfclose(bf);
#ifdef notdef
    bf->bf_ref = 0;
#endif
    if (!hashdelete(nmbftbl, key))
        error("can't delete hash key `%s'", key);
}

STATIC statust
bfrealclose()                /* close all open batch files */
{
    struct closehook closehook;
    register struct closehook *chp = &closehook;

    chp->status = ST_OKAY;
    if (nmbftbl != NULL)
        hashwalk(nmbftbl, closeone, (char *)chp);
    return chp->status;
}

STATIC
hfinstall(name)
char *name;
{
    register struct batchfile *bf;

    if (nmbftbl == NULL)
        nmbftbl = hashcreate(HASHFILSZ, (unsigned (*)())NULL);
    bf = (struct batchfile *)hashfetch(nmbftbl, name);
    if (bf != NULL)
        return;            /* error: name present */
    /* allocate, append & initialise a new entry */
    bf = (struct batchfile *)nemalloc(sizeof *bf);
    (void) memset((char *)bf, 0, sizeof *bf);
    bf->bf_name = strsave(name);    /* NEEDED? */
    bf->bf_str = NULL;    /* paranoia */
#ifdef notdef
    bf->bf_ref = 0;
#endif
    bf->bf_lines = FLUSHEVERY;
    if (!hashstore(nmbftbl, bf->bf_name, (HASHDATUM)bf))
        error("can't store under hash key `%s'", name);
}

/*
 * search the batchfile cache for "name"; return the corresponding
 * open master batch file, if any.
 */
STATIC struct batchfile *
bfisopen(name)
char *name;
{
    return nmbftbl == NULL? NULL:
        (struct batchfile *)hashfetch(nmbftbl, name);
}