/* Copyright (C) 1993, 2000 Aladdin Enterprises.  All rights reserved.
  
  This program is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License version 2
  as published by the Free Software Foundation.


  This software is provided AS-IS with no warranty, either express or
  implied. That is, this program is distributed in the hope that it will 
  be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details

  You should have received a copy of the GNU General Public License along
  with this program; if not, write to the Free Software Foundation, Inc.,
  59 Temple Place, Suite 330, Boston, MA, 02111-1307.
  
  For more information about licensing, please refer to
  http://www.ghostscript.com/licensing/. For information on
  commercial licensing, go to http://www.artifex.com/licensing/ or
  contact Artifex Software, Inc., 101 Lucas Valley Road #110,
  San Rafael, CA  94903, U.S.A., +1(415)492-9861.
*/

/* $Id: gsiodev.c,v 1.7 2002/02/21 22:24:52 giles Exp $ */
/* IODevice implementation for Ghostscript */
#include "errno_.h"
#include "string_.h"
#include "unistd_.h"
#include "gx.h"
#include "gserrors.h"
#include "gp.h"
#include "gscdefs.h"
#include "gsparam.h"
#include "gsstruct.h"
#include "gxiodev.h"

/* Import the IODevice table from gconf.c. */
extern_gx_io_device_table();

/* Define a table of local copies of the IODevices, */
/* allocated at startup.  This just postpones the day of reckoning.... */
private gx_io_device **io_device_table;

private_st_io_device();
gs_private_st_ptr(st_io_device_ptr, gx_io_device *, "gx_io_device *",
		  iodev_ptr_enum_ptrs, iodev_ptr_reloc_ptrs);
gs_private_st_element(st_io_device_ptr_element, gx_io_device *,
      "gx_io_device *[]", iodev_ptr_elt_enum_ptrs, iodev_ptr_elt_reloc_ptrs,
		      st_io_device_ptr);

/* Define the OS (%os%) device. */
iodev_proc_fopen(iodev_os_fopen);
iodev_proc_fclose(iodev_os_fclose);
private iodev_proc_delete_file(os_delete);
private iodev_proc_rename_file(os_rename);
private iodev_proc_file_status(os_status);
private iodev_proc_enumerate_files(os_enumerate);
private iodev_proc_get_params(os_get_params);
const gx_io_device gs_iodev_os =
{
    "%os%", "FileSystem",
    {iodev_no_init, iodev_no_open_device,
     NULL /*iodev_os_open_file */ , iodev_os_fopen, iodev_os_fclose,
     os_delete, os_rename, os_status,
     os_enumerate, gp_enumerate_files_next, gp_enumerate_files_close,
     os_get_params, iodev_no_put_params
    }
};

/* ------ Initialization ------ */

init_proc(gs_iodev_init);	/* check prototype */
int
gs_iodev_init(gs_memory_t * mem)
{				/* Make writable copies of all IODevices. */
    gx_io_device **table =
	gs_alloc_struct_array(mem, gx_io_device_table_count,
			      gx_io_device *, &st_io_device_ptr_element,
			      "gs_iodev_init(table)");
    int i, j;
    int code = 0;

    if (table == 0)
	return_error(gs_error_VMerror);
    for (i = 0; i < gx_io_device_table_count; ++i) {
	gx_io_device *iodev =
	    gs_alloc_struct(mem, gx_io_device, &st_io_device,
			    "gs_iodev_init(iodev)");

	if (iodev == 0)
	    goto fail;
	table[i] = iodev;
	memcpy(table[i], gx_io_device_table[i], sizeof(gx_io_device));
    }
    io_device_table = table;
    code = gs_register_struct_root(mem, NULL, (void **)&io_device_table,
				   "io_device_table");
    if (code < 0)
	goto fail;
    /* Run the one-time initialization of each IODevice. */
    for (j = 0; j < gx_io_device_table_count; ++j)
	if ((code = (table[j]->procs.init)(table[j], mem)) < 0)
	    goto f2;
    return 0;
 f2:
    /****** CAN'T FIND THE ROOT ******/
    /*gs_unregister_root(mem, root, "io_device_table");*/
 fail:
    for (; i >= 0; --i)
	gs_free_object(mem, table[i - 1], "gs_iodev_init(iodev)");
    gs_free_object(mem, table, "gs_iodev_init(table)");
    io_device_table = 0;
    return (code < 0 ? code : gs_note_error(gs_error_VMerror));
}

/* ------ Default (unimplemented) IODevice procedures ------ */

int
iodev_no_init(gx_io_device * iodev, gs_memory_t * mem)
{
    return 0;
}

int
iodev_no_open_device(gx_io_device * iodev, const char *access, stream ** ps,
		     gs_memory_t * mem)
{
    return_error(gs_error_invalidfileaccess);
}

int
iodev_no_open_file(gx_io_device * iodev, const char *fname, uint namelen,
		   const char *access, stream ** ps, gs_memory_t * mem)
{
    return_error(gs_error_invalidfileaccess);
}

int
iodev_no_fopen(gx_io_device * iodev, const char *fname, const char *access,
	       FILE ** pfile, char *rfname, uint rnamelen)
{
    return_error(gs_error_invalidfileaccess);
}

int
iodev_no_fclose(gx_io_device * iodev, FILE * file)
{
    return_error(gs_error_ioerror);
}

int
iodev_no_delete_file(gx_io_device * iodev, const char *fname)
{
    return_error(gs_error_invalidfileaccess);
}

int
iodev_no_rename_file(gx_io_device * iodev, const char *from, const char *to)
{
    return_error(gs_error_invalidfileaccess);
}

int
iodev_no_file_status(gx_io_device * iodev, const char *fname, struct stat *pstat)
{
    return_error(gs_error_undefinedfilename);
}

file_enum *
iodev_no_enumerate_files(gx_io_device * iodev, const char *pat, uint patlen,
			 gs_memory_t * memory)
{
    return NULL;
}

int
iodev_no_get_params(gx_io_device * iodev, gs_param_list * plist)
{
    return 0;
}

int
iodev_no_put_params(gx_io_device * iodev, gs_param_list * plist)
{
    return param_commit(plist);
}

/* ------ %os% ------ */

/* The fopen routine is exported for %null. */
int
iodev_os_fopen(gx_io_device * iodev, const char *fname, const char *access,
	       FILE ** pfile, char *rfname, uint rnamelen)
{
    errno = 0;
    *pfile = gp_fopen(fname, access);
    if (*pfile == NULL)
	return_error(gs_fopen_errno_to_code(errno));
    if (rfname != NULL)
	strcpy(rfname, fname);
    return 0;
}

/* The fclose routine is exported for %null. */
int
iodev_os_fclose(gx_io_device * iodev, FILE * file)
{
    fclose(file);
    return 0;
}

private int
os_delete(gx_io_device * iodev, const char *fname)
{
    return (unlink(fname) == 0 ? 0 : gs_error_ioerror);
}

private int
os_rename(gx_io_device * iodev, const char *from, const char *to)
{
    return (rename(from, to) == 0 ? 0 : gs_error_ioerror);
}

private int
os_status(gx_io_device * iodev, const char *fname, struct stat *pstat)
{				/* The RS/6000 prototype for stat doesn't include const, */
    /* so we have to explicitly remove the const modifier. */
    return (stat((char *)fname, pstat) < 0 ? gs_error_undefinedfilename : 0);
}

private file_enum *
os_enumerate(gx_io_device * iodev, const char *pat, uint patlen,
	     gs_memory_t * mem)
{
    return gp_enumerate_files_init(pat, patlen, mem);
}

private int
os_get_params(gx_io_device * iodev, gs_param_list * plist)
{
    int code;
    int i0 = 0, i2 = 2;
    bool btrue = true, bfalse = false;
    int BlockSize;
    long Free, LogicalSize;

    /*
     * Return fake values for BlockSize and Free, since we can't get the
     * correct values in a platform-independent manner.
     */
    BlockSize = 1024;
    LogicalSize = 2000000000 / BlockSize;	/* about 2 Gb */
    Free = LogicalSize * 3 / 4;			/* about 1.5 Gb */

    if (
	(code = param_write_bool(plist, "HasNames", &btrue)) < 0 ||
	(code = param_write_int(plist, "BlockSize", &BlockSize)) < 0 ||
	(code = param_write_long(plist, "Free", &Free)) < 0 ||
	(code = param_write_int(plist, "InitializeAction", &i0)) < 0 ||
	(code = param_write_bool(plist, "Mounted", &btrue)) < 0 ||
	(code = param_write_bool(plist, "Removable", &bfalse)) < 0 ||
	(code = param_write_bool(plist, "Searchable", &btrue)) < 0 ||
	(code = param_write_int(plist, "SearchOrder", &i2)) < 0 ||
	(code = param_write_bool(plist, "Writeable", &btrue)) < 0 ||
	(code = param_write_long(plist, "LogicalSize", &LogicalSize)) < 0
	)
	return code;
    return 0;
}

/* ------ Utilities ------ */

/* Get the N'th IODevice from the known device table. */
gx_io_device *
gs_getiodevice(int index)
{
    if (index < 0 || index >= gx_io_device_table_count)
	return 0;		/* index out of range */
    return io_device_table[index];
}

/* Look up an IODevice name. */
/* The name may be either %device or %device%. */
gx_io_device *
gs_findiodevice(const byte * str, uint len)
{
    int i;

    if (len > 1 && str[len - 1] == '%')
	len--;
    for (i = 0; i < gx_io_device_table_count; ++i) {
	gx_io_device *iodev = io_device_table[i];
	const char *dname = iodev->dname;

	if (dname && strlen(dname) == len + 1 && !memcmp(str, dname, len))
	    return iodev;
    }
    return 0;
}

/* ------ Accessors ------ */

/* Get IODevice parameters. */
int
gs_getdevparams(gx_io_device * iodev, gs_param_list * plist)
{				/* All IODevices have the Type parameter. */
    gs_param_string ts;
    int code;

    param_string_from_string(ts, iodev->dtype);
    code = param_write_name(plist, "Type", &ts);
    if (code < 0)
	return code;
    return (*iodev->procs.get_params) (iodev, plist);
}

/* Put IODevice parameters. */
int
gs_putdevparams(gx_io_device * iodev, gs_param_list * plist)
{
    return (*iodev->procs.put_params) (iodev, plist);
}

/* Convert an OS error number to a PostScript error */
/* if opening a file fails. */
int
gs_fopen_errno_to_code(int eno)
{				/* Different OSs vary widely in their error codes. */
    /* We try to cover as many variations as we know about. */
    switch (eno) {
#ifdef ENOENT
	case ENOENT:
	    return_error(gs_error_undefinedfilename);
#endif
#ifdef ENOFILE
#  ifndef ENOENT
#    define ENOENT ENOFILE
#  endif
#  if ENOFILE != ENOENT
	case ENOFILE:
	    return_error(gs_error_undefinedfilename);
#  endif
#endif
#ifdef ENAMETOOLONG
	case ENAMETOOLONG:
	    return_error(gs_error_undefinedfilename);
#endif
#ifdef EACCES
	case EACCES:
	    return_error(gs_error_invalidfileaccess);
#endif
#ifdef EMFILE
	case EMFILE:
	    return_error(gs_error_limitcheck);
#endif
#ifdef ENFILE
	case ENFILE:
	    return_error(gs_error_limitcheck);
#endif
	default:
	    return_error(gs_error_ioerror);
    }
}
