Complete Linux/Complete Linux.iso/docs/apps/database/ingres04.lzh/source/libq/IIingres.c

C/C++ Source or Header | 1993-01-18 | 4.0 KB | 191 lines

# include    <ingres.h>
# include    <symbol.h>
# include    <opsys.h>
# include    <aux.h>
# include    "IIglobals.h"
# include    <pipes.h>
# include    <signal.h>

# undef        CLOSED
# define    CLOSED    '?'


char    *IImainpr =    "ingres";

char    IIPathname[41];

/*
**    IIingres opens the needed pipes and
**    forks an ingres process.
**
**    ingres recognizes the EQUEL flag followed by
**    three control characters as being an equel processes
**
**    parameters to ingres are passed directly. only
**    the first 9 are counted.
*/

IIingres(p1, p2, p3, p4, p5, p6, p7, p8, p9)
char    *p1, *p2, *p3, *p4, *p5, *p6, *p7, *p8, *p9;
{
    int        pipes[4];        /* pipe vector buffer */
    char        eoption[15];    /* dummy variable to hold -EQUEL option */
    register char    *cp;
    char        *argv[12];
    register char    **ap;
    extern void    IIresync();
    extern void    *(IIinterrupt)();
    pb_t        pb;

#    ifdef xETR1
    if (IIdebug)
        printf("IIingres\n");
#    endif
    /* test if ingres is already invoked */
    if (IIingpid)
        IIsyserr("Attempt to invoke INGRES twice");

    IIgetpath();
    /* open INGRES pipes */
    if (pipe(&pipes[0]) || pipe(&pipes[2]))
        IIsyserr("pipe error in IIingres");

    IIw_down = pipes[1];    /* file desc for equel->parser */
    IIr_down = pipes[2];    /* file desc for parser->equel */

    /* catch interupts if they are not being ignored */
    if (signal(SIGINT, SIG_IGN) != SIG_IGN)
        signal(SIGINT, IIresync);

    /* set up equel option flag */
    cp = eoption;
    *cp++ = '-';
    *cp++ = EQUEL;
    *cp++ = pipes[0] | 0100;
    *cp++ = pipes[1] | 0100;
    *cp++ = CLOSED;
    *cp++ = pipes[3] | 0100;
    *cp++ = CLOSED;    /* this will be the equel->ovqp pipe in the future */
    *cp++ = CLOSED;    /* old ovqp->equel pipe */
    /* put "6.3" at end of flag for OVQP to not do flush after
     * every tuple
     */
    *cp++ = '6';
    *cp++ = '.';
    *cp++ = '3';
    *cp = '\0';
    if (cp - eoption >= sizeof eoption)
        IIsyserr("IIingres: too big an eoption");

    if ((IIingpid = fork()) < 0)
        IIsyserr("IIingres:cant fork %d", IIingpid);
    /* if parent, close the unneeded files and return */
    if (IIingpid)
    {
        if (close(pipes[0]) || close(pipes[3]))
            IIsyserr("close error 1 in IIingres");
        IIinput = IIr_down;
        IIpb_prime(&pb, PB_NOTYPE);
#        ifdef xETR1
        if (IIdebug)
            printf("calling ingres with '%s' database %s\n", eoption, p1);
#        endif
        return;
    }
    /* the child overlays /usr/bin/ingres */
    ap = argv;
    *ap++ = "ingres";
    *ap++ = eoption;
    *ap++ = p1;
    *ap++ = p2;
    *ap++ = p3;
    *ap++ = p4;
    *ap++ = p5;
    *ap++ = p6;
    *ap++ = p7;
    *ap++ = p8;
    *ap++ = p9;
    *ap = 0;
    execvp(IImainpr, argv);
    IIsyserr("cannot exec INGRES in IIingres");
}

/*
**  IIGETPATH -- initialize the IIPathname variable
**
**    Parameters:
**        none
**
**    Returns:
**        none
**
**    Side Effects:
**        Sets IIPathname to the home directory of the USERINGRES
**        [unix.h] user.
**
**    Called By:
**        IIingres.c
**
**    History:
**        3/26/79 -- (marc) written
*/

IIgetpath()
{
    char            line[MAXLINE + 1];
    static char        reenter;
    register int        i;
    register char        *lp;
    struct iob        iobuf;
    char            *field[UF_NFIELDS];

    if (reenter)
        return;
    else
        reenter++;

    if ((i = IIfopen("/etc/passwd", &iobuf)) < 0)
        IIsyserr("IIgetpath: no /etc/passwd");

    do
    {
        /* get a line from the passwd file */
        i = 0;
        for (lp = line; (*lp = IIgetc(&iobuf)) != '\n'; lp++)
        {
            if (*lp == -1)
                IIsyserr("IIgetpath: no user 'ingres' in /etc/passwd");
            if (++i > sizeof line - 1)
            {
                *lp = '\0';
                IIsyserr("IIgetpath: line overflow: \"%s\"",
                line);
            }
        }
        *lp = '\0';
        for (i = 0, lp = line; *lp != '\0'; lp++)
        {
            if (*lp == ':')
            {
                *lp = '\0';
                if (i > UF_NFIELDS)
                    IIsyserr("IIgetpath: too many fields in passwd \"%s\"",
                    line);
                field[i++] = lp + 1;
            }
        }
        /* check for enough fields for valid entry */
        if (i < 3)
            IIsyserr("IIgetpath: too few fields \"%s\"",
            line);
    }  while (!IIsequal(line, USERINGRES));
    IIclose(&iobuf);

    /* check that pathname won't overflow static buffer */
    if (field[i - 1] - field[i - 2] > sizeof IIPathname)
        IIsyserr("IIgetpath: path too long \"%s\"", field[i - 2]);

    /* move pathname into buffer */
    IIbmove(field[i - 2], IIPathname, field[i - 1] - field[i - 2]);
}