/*								-*-C-*-
 *	HUMBLE - Functions for hacking inferiors.
 */

#include <c-env.h>
#include <errno.h>
#include <sys/usysio.h>
#include <sys/usysig.h>
#include <sys/file.h>
#include <sysits.h>
#include "humble.h"

#if !SYS_ITS
#error This is an ITS specific file!
#endif

static int gename();		/* Generates sixbit words */
static void uclose();		/* Kills jobs */

static int _uiojob[OPEN_UFX_MAX+1];	/* non-0 if this is a job UFX */


/* Creates an inferior, returns an FD or -1 if failure */
int j_create()
{
    int fd, ufx, jname, val;

    USYS_BEG();

    if ((fd = _uiofd()) == -1 || !(ufx = _uiofx()))
	USYS_RETERR(EMFILE);

    _uiobsize[ufx] = 9;
    _uioflgs[ufx] |= _UIO_HANDPACK;	/* Block mode channel */

    do {
	jname = gename();
	val = SYSCALL5("open", SC_IMC(_BIO), _uioch[ufx],
		       SC_SIX("usr"), SC_IMM(0), &jname);
    } while (val == _EEXFL);

    if (val) USYS_RETERR(ENOENT);

    _openufx(ufx, (O_WRONLY | O_CREAT | O_TRUNC | O_BSIZE_9));
    _uiojob[ufx] = -1;
    _uioufx[fd] = ufx;
    USYS_RET(fd);
}

static int gename()
{
#asm
    .gensym 1,
#endasm
}

/* Kills the specified inferior, always wins except if given
 * a losing FD, in which case it returns -1, otherwise 0.
 */
int j_kill(fd)
  int fd;
{
    int ufx;

    USYS_BEG();

    if (fd < 0 || fd >= OPEN_MAX || !(ufx = _uioufx[fd]) || !_uiojob[ufx])
	USYS_RETERR(EBADF);

    uclose(_uioch[ufx]);
    _uiozcnt[ufx] = 0;		/* Channel now closed, so forget these */
    close(fd);

    USYS_RET(0);
}

/* Why the hell isn't there a .CALL version of this? */
static void uclose(ch)
  int ch;
{
#asm
    hrlz 1,-1(p)
    lsh 1,5
    ior 1,[.uclose 0,]
    xct 1
#endasm
}

/* Copies COUNT words from BUF into the inferior starting at ADDR.
 * Creating memory if it doesn't exist.  Always returns 0 minus the 
 * number of words left to be written.
 * Possible errors:
 *  - Bad FD.
 *  - System doesn't have enough virtual address space (temporary).
 *  - Tried to write beyond end of address space.
 *  - Can't write into a foreign job (currently impossible).
 */
int j_write(fd, addr, buf, count)
    int fd, addr, *buf, count;
{
    return 0;
}

/* Copies COUNT words into BUF from the inferior starting at ADDR.
 * Always returns 0 minus the number of words left to be read.
 * Possible errors:
 *  - Bad FD.
 *  - Tried to read nonexistent memory.
 */
int j_read(fd,  addr, buf, count)
    int fd, addr, *buf, count;
{
    return 0;
}
/* Writes a PDUMP file for the job on the freshly opened file.
 * Returns 0 if we win and -1 if we lose.
 * Possible errors:
 *  - Bad FD for job.
 *  - File FD isn't open to DSK.
 *  - DSK or directory full, etc.
 */
int j_dump(job_fd, file_fd)
    int job_fd, file_fd;
{
    return 0;
}