/* io_win32.c
 *  Copyright: (When this is determined...it will go here)
 *  CVS Info
 *      $Id: io_win32.c,v 1.19 2002/07/25 02:04:38 mongo Exp $
 *  Overview:
 *      This is the Parrot IO OS layer for Win32 platforms.
 *  Data Structure and Algorithms:
 *  History:
 *      Initially written by Melvin Smith
 *  Notes:
 *  References:
 *      Win32 System Programming, 2nd Edition
 */

#include "parrot/parrot.h"

#ifdef PIO_OS_WIN32

#  include <tchar.h>

/* Defined at bottom */
extern ParrotIOLayerAPI pio_win32_layer_api;

ParrotIOLayer pio_win32_layer = {
    NULL,
    "win32",
    PIO_L_TERMINAL,
    &pio_win32_layer_api,
    0, 0
};


/*
 * Currently keeping layer prototypes local to each layer
 * file.
 */

INTVAL PIO_win32_init(theINTERP, ParrotIOLayer *layer);
ParrotIO *PIO_win32_open(theINTERP, ParrotIOLayer *layer,
                         const char *spath, INTVAL flags);
ParrotIO *PIO_win32_fdopen(theINTERP, ParrotIOLayer *layer,
                           PIOHANDLE fd, INTVAL flags);
INTVAL PIO_win32_close(theINTERP, ParrotIOLayer *layer, ParrotIO *io);
void PIO_win32_flush(theINTERP, ParrotIOLayer *layer, ParrotIO *io);
size_t PIO_win32_read(theINTERP, ParrotIOLayer *layer,
                      ParrotIO *io, void *buffer, size_t len);
size_t PIO_win32_write(theINTERP, ParrotIOLayer *layer,
                       ParrotIO *io, const void *buffer, size_t len);
INTVAL PIO_win32_puts(theINTERP, ParrotIOLayer *l, ParrotIO *io,
                      const char *s);
INTVAL PIO_win32_seek(theINTERP, ParrotIOLayer *l, ParrotIO *io,
                      INTVAL hi, INTVAL lo, INTVAL whence);
PIOOFF_T PIO_win32_tell(theINTERP, ParrotIOLayer *l, ParrotIO *io);


/* Convert to platform specific bit open flags */
INTVAL
flags_to_win32(INTVAL flags, DWORD * fdwAccess,
               DWORD * fdwShareMode, DWORD * fdwCreate)
{
    if ((flags & (PIO_F_WRITE | PIO_F_READ)) == (PIO_F_WRITE | PIO_F_READ)) {
        *fdwAccess = GENERIC_WRITE | GENERIC_READ;
        *fdwCreate = CREATE_ALWAYS;
    }
    else if (flags & PIO_F_WRITE) {
        *fdwAccess = GENERIC_WRITE;
        *fdwCreate = CREATE_ALWAYS;
    }
    else if (flags & PIO_F_READ) {
        *fdwAccess = GENERIC_READ;
        *fdwCreate = OPEN_EXISTING;
    }

    *fdwShareMode = FILE_SHARE_READ;
    if ((flags & PIO_F_TRUNC) && (flags & PIO_F_WRITE) &&
        (*fdwCreate & CREATE_ALWAYS) == 0)
        *fdwCreate |= TRUNCATE_EXISTING;
    else if (flags & PIO_F_APPEND) {
    }
    return 1;
}


/*
 * Setup standard streams.
 */
INTVAL
PIO_win32_init(theINTERP, ParrotIOLayer *layer)
{
    HANDLE h;
    if ((h = GetStdHandle(STD_INPUT_HANDLE)) != INVALID_HANDLE_VALUE) {
        PIO_STDIN(interpreter) =
            PIO_win32_fdopen(interpreter, layer, h, PIO_F_READ);
    }
    else {
        return -1;
    }
    if ((h = GetStdHandle(STD_OUTPUT_HANDLE))
        != INVALID_HANDLE_VALUE) {
        PIO_STDOUT(interpreter) =
            PIO_win32_fdopen(interpreter, layer, h, PIO_F_WRITE);
    }
    else {
        return -2;
    }
    if ((h = GetStdHandle(STD_ERROR_HANDLE)) != INVALID_HANDLE_VALUE) {
        PIO_STDERR(interpreter) =
            PIO_win32_fdopen(interpreter, layer, h, PIO_F_WRITE);
    }
    else {
        return -3;
    }
    return 0;
}


INTVAL
PIO_win32_getblksize(PIOHANDLE fd)
{
    /* Hard coded for now */
    return PIO_BLKSIZE;
}


ParrotIO *
PIO_win32_open(theINTERP, ParrotIOLayer *layer,
               const char *spath, INTVAL flags)
{
    ParrotIO *io;
    int type;
    DWORD fAcc, fShare, fCreat;
    PIOHANDLE fd;
    type = PIO_TYPE_FILE;
#  if 0
    if ((Interp_flags_TEST(interpreter, PARROT_DEBUG_FLAG)) != 0) {
        fprintf(stderr, "PIO_win32_open: %s\n", spath);
    }
#  endif
    if ((flags & (PIO_F_WRITE | PIO_F_READ)) == 0)
        return (ParrotIO *)NULL;

    /* Set open flags - <, >, >>, +<, +> */
    /* add ? and ! for block/non-block */
    if (flags_to_win32(flags, &fAcc, &fShare, &fCreat) < 0)
        return (ParrotIO *)NULL;

    /* Only files for now */
    flags |= PIO_F_FILE;

    fd = CreateFile(spath, fAcc, 0, NULL, fCreat, FILE_ATTRIBUTE_NORMAL, NULL);
    if (fd != INVALID_HANDLE_VALUE) {
        io = PIO_new(interpreter, NULL, type, flags, 0);
        io->fd = fd;
        return io;
    }
    else {
        int err = GetLastError();
        if(err) {}
    }

    return (ParrotIO *)NULL;
}


ParrotIO *
PIO_win32_fdopen(theINTERP, ParrotIOLayer *layer, PIOHANDLE fd, INTVAL flags)
{
    ParrotIO *io;
    INTVAL mode;
    mode = 0;

    if (PIO_win32_isatty(fd))
        flags |= PIO_F_CONSOLE;
    io = PIO_new(interpreter, NULL, PIO_F_FILE, flags, mode);
    io->fd = fd;
    return io;
}


INTVAL
PIO_win32_close(theINTERP, ParrotIOLayer *layer, ParrotIO *io)
{
    if (io && io->fd != INVALID_HANDLE_VALUE) {
        CloseHandle(io->fd);
        io->fd = INVALID_HANDLE_VALUE;
    }
    return 0;
}


INTVAL
PIO_win32_isatty(PIOHANDLE fd)
{
    DWORD ftype = GetFileType(fd);
    if (ftype == FILE_TYPE_CHAR)
        return 1;
    return 0;
}


void
PIO_win32_flush(theINTERP, ParrotIOLayer *layer, ParrotIO *io)
{
    /*
     * FlushFileBuffers won't work for console handles. From the MS help file:
     *
     * Windows NT: The function fails if hFile is a handle to console output. That is because console output is not buffered.
     * The function returns FALSE, and GetLastError returns ERROR_INVALID_HANDLE.
     * 
     * Windows 9x: The function does nothing if hFile is a handle to console output. That is because console output is not buffered.
     * The function returns TRUE, but it does nothing.
     */
    FlushFileBuffers(io->fd);
}


size_t
PIO_win32_read(theINTERP, ParrotIOLayer *layer, ParrotIO *io,
               void *buffer, size_t len)
{
    DWORD countread;
    if (ReadFile(io->fd, (LPVOID) buffer, (DWORD) len, &countread, NULL))
        return (size_t)countread;
    else {
        if (GetLastError() != NO_ERROR) {
            /* FIXME : An error occured */
        }
        else if (len > 0) {
            /* EOF if read 0 and bytes were requested */
            io->flags |= PIO_F_EOF;
        }
    }
    return 0;
}


size_t
PIO_win32_write(theINTERP, ParrotIOLayer *layer, ParrotIO *io,
                const void *buffer, size_t len)
{
    DWORD countwrote = 0;
    if (io
        && WriteFile(io->fd, (LPCSTR) buffer, (DWORD) len, &countwrote, NULL))
        return countwrote;
    /* FIXME: Set error flag */
    return (size_t)-1;
}


/*
 * puts() tries WriteConsole() first, then WriteFile(), whereas
 * write() calls WriteFile() only. I've also read that WriteFile
 * will call WriteConsole if the handle is the right type (console) so
 * I suppose this is saving a function call since puts is probably
 * used for consoles a lot.
 */
INTVAL
PIO_win32_puts(theINTERP, ParrotIOLayer *l, ParrotIO *io, const char *s)
{
    DWORD len, countwrote;
    len = _tcslen((LPCSTR) s);
    if (WriteConsole(io->fd, (LPCSTR) s, len, &countwrote, NULL)
        || WriteFile(io->fd, (LPCSTR) s, len, &countwrote, NULL))
        return countwrote;
    return -1;
}


/*
 * Hard seek
 */
INTVAL
PIO_win32_seek(theINTERP, ParrotIOLayer *l, ParrotIO *io,
               INTVAL hi, INTVAL lo, INTVAL whence)
{
    PIOOFF_T p, offset;
    offset.LowPart = lo;
    offset.HighPart = hi;
    p.LowPart = SetFilePointer(io->fd, offset.LowPart,
                               &offset.HighPart, whence);
    if (p.LowPart == 0xFFFFFFFF && (GetLastError() != NO_ERROR)) {
        /* Error - exception */
        return -1;
    }
    io->fpos = p;
    return 0;
}


PIOOFF_T
PIO_win32_tell(theINTERP, ParrotIOLayer *l, ParrotIO *io)
{
    PIOOFF_T p = piooffsetzero;
    p.LowPart = SetFilePointer(io->fd, 0, &p.HighPart, FILE_CURRENT);
    if (p.LowPart == 0xFFFFFFFF && GetLastError() != NO_ERROR) {
        /* FIXME: Error - exception */
    }
    return p;
}



ParrotIOLayerAPI pio_win32_layer_api = {
    PIO_win32_init,
    PIO_base_new_layer,
    PIO_base_delete_layer,
    PIO_null_push_layer,
    PIO_null_pop_layer,
    PIO_win32_open,
    PIO_null_open2,
    PIO_null_open3,
    PIO_null_open_async,
    PIO_win32_fdopen,
    PIO_win32_close,
    PIO_win32_write,
    PIO_null_write_async,
    PIO_win32_read,
    PIO_null_read_async,
    PIO_null_flush,
    PIO_win32_seek,
    PIO_win32_tell,
    PIO_null_setbuf,
    PIO_null_setlinebuf,
    PIO_null_getcount,
    PIO_null_fill,
    PIO_win32_puts,
    PIO_null_gets,
    PIO_null_eof
};



#endif /* PIO_OS_WIN32 */


/*
 * Local variables:
 * c-indentation-style: bsd
 * c-basic-offset: 4
 * indent-tabs-mode: nil
 * End:
 *
 * vim: expandtab shiftwidth=4:
*/
