Usenet 1994 January/usenetsourcesnewsgroupsinfomagicjanuary1994.iso/sources/unix/volume13/vn.jan.88/part04/pagefile.c

C/C++ Source or Header | 1988-01-30 | 4.0 KB | 225 lines

/*
** vn news reader.
**
** pagefile.c - routines to deal with page display tempfile
**
** see copyright disclaimer / history in vn.c source file
*/

#include <stdio.h>

#ifdef SYSV
#include <sys/types.h>
#include <fcntl.h>
#endif

#include <sys/file.h>

#include "tune.h"
#include "node.h"
#include "page.h"

extern int Ncount,Lrec,L_allow,Cur_page,C_allow;
extern NODE **Newsorder;
extern PAGE Page;
extern int Digest;

extern char *Aformat;

extern char *T_head, *F_head, *L_head;

static int Tdes;    /* temp file descriptor */
static int Pgsize;    /* block size for seeking file */

static NODE *Curgp = NULL;    /* current newsgroup being written */
static int Order = 0;        /* order counter */

/*
    routines which deal with the temp file containing
    display pages.  Note the "invisible" file feature -
    tempfile is unlinked from /usr/tmp immediately.  when
    Tdes is closed by UNIX the disk space will be given back.
*/

temp_open ()
{
    char tmpart [L_tmpnam];
    Lrec = -1;
    tmpnam (tmpart);
    Pgsize = sizeof (HEAD) + L_allow * sizeof(BODY);
    if ((Tdes = open(tmpart,O_RDWR|O_CREAT)) < 0)
        printex ("can't open %s",tmpart);
    unlink (tmpart);
}

/*
** set newsgroup for tempfile write
*/
fw_group(ng,new,sub,rd,look)
char *ng;
int new;
int sub;
int rd;
int look;
{
    NODE *hashfind();

    if (Curgp != NULL && Page.h.artnum > 0)
        fw_flush();

    if ((Curgp = hashfind(ng)) == NULL)
        printex("fw_group - non-existent newsgroup, \"%s\"",ng);
    if (Curgp->order >= 0)
        printex("fw_group - repeat call on newsgroup, \"%s\"",ng);
    Curgp->order = Order;
    ++Order;
    fw_chg(new,sub,rd,look);
    Curgp->pages = 0;
    Curgp->pnum = Lrec+1;
    Page.h.name = Curgp->nd_name;
    Page.h.group = Curgp;
    Page.h.artnum = 0;
}

fw_chg(new,sub,rd,look)
int new;
int sub;
int rd;
int look;
{
    Curgp->flags &= ~(FLG_NEW|FLG_SUB|FLG_SEARCH);
    if (new)
        Curgp->flags |= FLG_NEW;
    if (sub)
        Curgp->flags |= FLG_SUB;
    if (look)
        Curgp->flags |= FLG_SEARCH;
    Curgp->rdnum = Curgp->orgrd = Curgp->pgrd = rd;
}

/*
** write article to temp file.
*/
fw_art(anum,subj,lines,author)
int anum;
char *subj;
char *lines;
char *author;
{
    char tbuf[RECLEN];
    int idx;

    form_title(tbuf,subj,lines,author,anum);
    idx = Page.h.artnum;
    strcpy((Page.b)[idx].art_t, tbuf);
    (Page.b)[idx].art_id = anum;
    (Page.b)[idx].art_mark = ' ';

    ++(Page.h.artnum);
    if (Page.h.artnum >= L_allow)
        fw_flush();
}

fw_done()
{
    if (Curgp != NULL && Page.h.artnum > 0)
    {
        /* correct if server was lying at fw_group() */
        Curgp->flags |= FLG_SEARCH;
        fw_flush();
    }
}

static
fw_flush()
{
    ++(Curgp->pages);
    ++Lrec;
    Curgp->flags |= FLG_PAGE;
    do_write();
    Page.h.artnum = 0;
}

find_page (n)
int n;
{
    long off,lseek();
    int i,last;
    Cur_page = n;
    off = Pgsize;
    off *= (long) n;
    lseek (Tdes, off, 0);
    if (read(Tdes, (char *) &(Page.h), sizeof(HEAD)) < sizeof(HEAD))
        printex("bad temp file read");
    i = Pgsize - sizeof(HEAD);
    if (read(Tdes, (char *) Page.b, i) < i)
        printex("bad temp file read");
    last = -1;
    for (i=0; i < Ncount; ++i)
    {
        if ((Newsorder[i])->pages > 0)
        {
            if ((Newsorder[i])->pnum > n)
                break;
            last = i;
        }
    }
    if (last < 0)
        printex ("can't find page %d",n);
    Page.h.group = Newsorder[last];
    Page.h.name = (Page.h.group)->nd_name;
    vns_gset(Page.h.name);
}

write_page ()
{
    long off,lseek();
    if (!Digest)
    {
        off = Pgsize;
        off *= (long) Cur_page;
        lseek (Tdes, off, 0);
        do_write();
    }
}

static do_write()
{
    int num;

    if (write(Tdes, (char *) &(Page.h), sizeof(HEAD)) < sizeof(HEAD))
        printex ("Bad temp file write");
    num = L_allow * sizeof(BODY);
    if (write(Tdes, (char *) Page.b, num) < num)
        printex ("Bad temp file write");
}

form_title (t,fn,fl,ff,n)
char *t,*fn,*fl,*ff;
int n;
{
    char *ptr,*index();
    int i;

    if ((ptr = index(ff,'(')) != NULL && strlen(ptr) > 3)
        ff = ptr;
    sprintf (t,TFORMAT,fn,fl,ff);
    sprintf(ff,Aformat,' ',' ',n);
    i = C_allow - strlen(ff) + 1;    /* remember newline in Aformat */
    t[i] = '\0';
    ctl_xlt(t);
    return (0);
}

/* replace control characters in titles */
static ctl_xlt(s)
char *s;
{
    while (*s != '\0')
    {
        if (*s < ' ')
            *s += 'A' - 1;
        ++s;
    }
}