/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public

    License as published by the Free Software Foundation; either

    version 2.1 of the License, or (at your option) any later version.

    This library 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

    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public

    License along with this library; if not, write to the Free Software

    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Carsten Griwodz

    griff@kom.tu-darmstadt.de

    based on linux/SDL_syscdrom.c by Sam Lantinga

*/

/* Functions for system-level CD-ROM audio control */

/*#define DEBUG_CDROM 1*/

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <errno.h>

#include <unistd.h>

#include <sys/ioctl.h>

#include <sys/devinfo.h>

#include <sys/mntctl.h>

#include <sys/statfs.h>

#include <sys/vmount.h>

#include <fstab.h>

#include <sys/scdisk.h>

#include "SDL_cdrom.h"

#include "../SDL_syscdrom.h"

/* The maximum number of CD-ROM drives we'll detect */

#define MAX_DRIVES	16	

/* A list of available CD-ROM drives */

static char *SDL_cdlist[MAX_DRIVES];

static dev_t SDL_cdmode[MAX_DRIVES];

/* The system-dependent CD control functions */

static const char *SDL_SYS_CDName(int drive);

static int         SDL_SYS_CDOpen(int drive);

static int         SDL_SYS_CDGetTOC(SDL_CD *cdrom);

static CDstatus    SDL_SYS_CDStatus(SDL_CD *cdrom, int *position);

static int         SDL_SYS_CDPlay(SDL_CD *cdrom, int start, int length);

static int         SDL_SYS_CDPause(SDL_CD *cdrom);

static int         SDL_SYS_CDResume(SDL_CD *cdrom);

static int         SDL_SYS_CDStop(SDL_CD *cdrom);

static int         SDL_SYS_CDEject(SDL_CD *cdrom);

static void        SDL_SYS_CDClose(SDL_CD *cdrom);

static int         SDL_SYS_CDioctl(int id, int command, void *arg);

/* Check a drive to see if it is a CD-ROM */

static int CheckDrive(char *drive, struct stat *stbuf)

{

    int is_cd;

    int cdfd;

    int ret;

    struct devinfo info;

    /* If it doesn't exist, return -1 */

    if ( stat(drive, stbuf) < 0 ) {

        return -1;

    }

    /* If it does exist, verify that it's an available CD-ROM */

    is_cd = 0;

    if ( S_ISCHR(stbuf->st_mode) || S_ISBLK(stbuf->st_mode) ) {

        cdfd = open(drive, (O_RDONLY|O_EXCL|O_NONBLOCK), 0);

        if ( cdfd >= 0 ) {

            ret = SDL_SYS_CDioctl( cdfd, IOCINFO, &info );

	    if ( ret < 0 ) {

		/* Some kind of error */

		is_cd = 0;

	    } else {

		if ( info.devtype == DD_CDROM ) {

		    is_cd = 1;

		} else {

		    is_cd = 0;

		}

	    }

            close(cdfd);

	}

#ifdef DEBUG_CDROM

	else

	{

            fprintf(stderr, "Could not open drive %s (%s)\n", drive, strerror(errno));

	}

#endif

    }

    return is_cd;

}

/* Add a CD-ROM drive to our list of valid drives */

static void AddDrive(char *drive, struct stat *stbuf)

{

	int i;

	if ( SDL_numcds < MAX_DRIVES ) {

		/* Check to make sure it's not already in our list.

	 	   This can happen when we see a drive via symbolic link.

		 */

		for ( i=0; i<SDL_numcds; ++i ) {

			if ( stbuf->st_rdev == SDL_cdmode[i] ) {

#ifdef DEBUG_CDROM

  fprintf(stderr, "Duplicate drive detected: %s == %s\n", drive, SDL_cdlist[i]);

#endif

				return;

			}

		}

		/* Add this drive to our list */

		i = SDL_numcds;

		if ( SDL_cdlist[i] == NULL ) {

			SDL_OutOfMemory();

			return;

		}

		SDL_cdmode[i] = stbuf->st_rdev;

		++SDL_numcds;

#ifdef DEBUG_CDROM

  fprintf(stderr, "Added CD-ROM drive: %s\n", drive);

#endif

	}

}

static void CheckMounts()

{

    char*          buffer;

    int            bufsz;

    struct vmount* ptr;

    int            ret;

    buffer = (char*)SDL_malloc(10);

    bufsz  = 10;

    if ( buffer==NULL )

    {

        fprintf(stderr, "Could not allocate 10 bytes in aix/SDL_syscdrom.c:CheckMounts\n" );

	exit ( -10 );

    }

    do

    {

	/* mntctrl() returns an array of all mounted filesystems */

        ret = mntctl ( MCTL_QUERY, bufsz, buffer );

        if ( ret == 0 )

        {

				   /* Buffer was too small, realloc.    */

            bufsz = *(int*)buffer; /* Required size is in first word.   */

				   /* (whatever a word is in AIX 4.3.3) */

				   /* int seems to be OK in 32bit mode. */

            SDL_free(buffer);

            buffer = (char*)SDL_malloc(bufsz);

            if ( buffer==NULL )

            {

                fprintf(stderr,

			"Could not allocate %d bytes in aix/SDL_syscdrom.c:CheckMounts\n",

			bufsz );

	        exit ( -10 );

            }

        }

	else if ( ret < 0 )

	{

#ifdef DEBUG_CDROM

            fprintf(stderr, "Error reading vmount structures\n");

#endif

	    return;

	}

    }

    while ( ret == 0 );

#ifdef DEBUG_CDROM

    fprintf ( stderr, "Read %d vmount structures\n",ret );

#endif

    ptr = (struct vmount*)buffer;

    do

    {

            switch(ptr->vmt_gfstype)

            {

            case MNT_CDROM :

                {

		    struct stat stbuf;

		    char*       text;

		    text = (char*)ptr + ptr->vmt_data[VMT_OBJECT].vmt_off;

#ifdef DEBUG_CDROM

  fprintf(stderr, "Checking mount path: %s mounted on %s\n",

	text, (char*)ptr + ptr->vmt_data[VMT_STUB].vmt_off );

#endif

		    if ( CheckDrive( text, &stbuf) > 0)

		    {

		        AddDrive( text, &stbuf);

		    }

                }

                break;

            default :

                break;

            }

            ptr = (struct vmount*)((char*)ptr + ptr->vmt_length);

            ret--;

    }

    while ( ret > 0 );

    free ( buffer );

}

static int CheckNonmounts()

{

#ifdef _THREAD_SAFE

    AFILE_t      fsFile = NULL;

    int          passNo = 0;

    int          ret;

    struct fstab entry;

    struct stat  stbuf;

    ret = setfsent_r( &fsFile, &passNo );

    if ( ret != 0 ) return -1;

    do

    {

        ret = getfsent_r ( &entry, &fsFile, &passNo );

        if ( ret == 0 ) {

            char* l = SDL_strrchr(entry.fs_spec,'/');

            if ( l != NULL ) {

                if ( !SDL_strncmp("cd",++l,2) ) {

#ifdef DEBUG_CDROM

                    fprintf(stderr,

			    "Found unmounted CD ROM drive with device name %s\n",

			    entry.fs_spec);

#endif

		    if ( CheckDrive( entry.fs_spec, &stbuf) > 0)

		    {

		        AddDrive( entry.fs_spec, &stbuf);

		    }

                }

            }

        }

    }

    while ( ret == 0 );

    ret = endfsent_r ( &fsFile );

    if ( ret != 0 ) return -1;

    return 0;

#else

    struct fstab* entry;

    struct stat  stbuf;

    setfsent();

    do

    {

        entry = getfsent();

        if ( entry != NULL ) {

            char* l = SDL_strrchr(entry->fs_spec,'/');

            if ( l != NULL ) {

                if ( !SDL_strncmp("cd",++l,2) ) {

#ifdef DEBUG_CDROM

                    fprintf(stderr,"Found unmounted CD ROM drive with device name %s", entry->fs_spec);

#endif

		    if ( CheckDrive( entry->fs_spec, &stbuf) > 0)

		    {

		        AddDrive( entry->fs_spec, &stbuf);

		    }

                }

            }

        }

    }

    while ( entry != NULL );

    endfsent();

#endif

}

int  SDL_SYS_CDInit(void)

{

	char *SDLcdrom;

	struct stat stbuf;

	/* Fill in our driver capabilities */

	SDL_CDcaps.Name = SDL_SYS_CDName;

	SDL_CDcaps.Open = SDL_SYS_CDOpen;

	SDL_CDcaps.GetTOC = SDL_SYS_CDGetTOC;

	SDL_CDcaps.Status = SDL_SYS_CDStatus;

	SDL_CDcaps.Play = SDL_SYS_CDPlay;

	SDL_CDcaps.Pause = SDL_SYS_CDPause;

	SDL_CDcaps.Resume = SDL_SYS_CDResume;

	SDL_CDcaps.Stop = SDL_SYS_CDStop;

	SDL_CDcaps.Eject = SDL_SYS_CDEject;

	SDL_CDcaps.Close = SDL_SYS_CDClose;

	/* Look in the environment for our CD-ROM drive list */

	SDLcdrom = SDL_getenv("SDL_CDROM");	/* ':' separated list of devices */

	if ( SDLcdrom != NULL ) {

		char *cdpath, *delim;

		if ( cdpath != NULL ) {

			SDLcdrom = cdpath;

			do {

				delim = SDL_strchr(SDLcdrom, ':');

				if ( delim ) {

					*delim++ = '\0';

				}

#ifdef DEBUG_CDROM

  fprintf(stderr, "Checking CD-ROM drive from SDL_CDROM: %s\n", SDLcdrom);

#endif

				if ( CheckDrive(SDLcdrom, &stbuf) > 0 ) {

					AddDrive(SDLcdrom, &stbuf);

				}

				if ( delim ) {

					SDLcdrom = delim;

				} else {

					SDLcdrom = NULL;

				}

			} while ( SDLcdrom );

		}

		/* If we found our drives, there's nothing left to do */

		if ( SDL_numcds > 0 ) {

			return(0);

		}

	}

	CheckMounts();

	CheckNonmounts();

	return 0;

}

/* General ioctl() CD-ROM command function */

static int SDL_SYS_CDioctl(int id, int command, void *arg)

{

    int retval;

    retval = ioctl(id, command, arg);

    if ( retval < 0 ) {

        SDL_SetError("ioctl() error: %s", strerror(errno));

    }

    return retval;

}

static const char *SDL_SYS_CDName(int drive)

{

	return(SDL_cdlist[drive]);

}

static int SDL_SYS_CDOpen(int drive)

{

    int   fd;

    char* lastsl;

    char* cdromname;

    /*

     * We found /dev/cd? drives and that is in our list. But we can

     * open only the /dev/rcd? versions of those devices for Audio CD.

     */

    lastsl = SDL_strrchr(cdromname,'/');

    if (lastsl) {

	*lastsl = 0;

	lastsl = SDL_strrchr(SDL_cdlist[drive],'/');

	if (lastsl) {

	    lastsl++;

	}

    }

#ifdef DEBUG_CDROM

    fprintf(stderr, "Should open drive %s, opening %s\n", SDL_cdlist[drive], cdromname);

#endif

    /*

     * Use exclusive access. Don't use SC_DIAGNOSTICS as xmcd does because they

     * require root priviledges, and we don't want that. SC_SINGLE provides

     * exclusive access with less trouble.

     */

    fd = openx(cdromname, O_RDONLY, NULL, SC_SINGLE);

    if ( fd < 0 )

    {

#ifdef DEBUG_CDROM

            fprintf(stderr, "Could not open drive %s (%s)\n", cdromname, strerror(errno));

#endif

    }

    else

    {

	struct mode_form_op cdMode;

	int                 ret;

#ifdef DEBUG_CDROM

	cdMode.action = CD_GET_MODE;

	ret = SDL_SYS_CDioctl(fd, DK_CD_MODE, &cdMode);

	if ( ret < 0 ) {

            fprintf(stderr,

	            "Could not get drive mode for %s (%s)\n",

		    cdromname, strerror(errno));

	} else {

	    switch(cdMode.cd_mode_form) {

		case CD_MODE1 :

                    fprintf(stderr,

	                "Drive mode for %s is %s\n",

		        cdromname, "CD-ROM Data Mode 1");

		    break;

		case CD_MODE2_FORM1 :

                    fprintf(stderr,

	                "Drive mode for %s is %s\n",

		        cdromname, "CD-ROM XA Data Mode 2 Form 1");

		    break;

		case CD_MODE2_FORM2 :

                    fprintf(stderr,

	                "Drive mode for %s is %s\n",

		        cdromname, "CD-ROM XA Data Mode 2 Form 2");

		    break;

		case CD_DA :

                    fprintf(stderr,

	                "Drive mode for %s is %s\n",

		        cdromname, "CD-DA");

		    break;

		default :

                    fprintf(stderr,

	                "Drive mode for %s is %s\n",

		        cdromname, "unknown");

		    break;

	    }

	}

#endif

	cdMode.action       = CD_CHG_MODE;

	cdMode.cd_mode_form = CD_DA;

	ret = SDL_SYS_CDioctl(fd, DK_CD_MODE, &cdMode);

	if ( ret < 0 ) {

#ifdef DEBUG_CDROM

            fprintf(stderr,

	            "Could not set drive mode for %s (%s)\n",

		    cdromname, strerror(errno));

#endif

            SDL_SetError("ioctl() error: Could not set CD drive mode, %s",

	                 strerror(errno));

	} else {

#ifdef DEBUG_CDROM

            fprintf(stderr,

	            "Drive mode for %s set to CD_DA\n",

		    cdromname);

#endif

	}

    }

    SDL_free(cdromname);

    return fd;

}

static int SDL_SYS_CDGetTOC(SDL_CD *cdrom)

{

    struct cd_audio_cmd cmd;

    struct cd_audio_cmd entry;

    int                 i;

    int                 okay;

    cmd.audio_cmds = CD_TRK_INFO_AUDIO;

    cmd.msf_flag   = FALSE;

    if ( SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd) < 0 ) {

	return -1;

    }

    okay = 0;

    cdrom->numtracks = cmd.indexing.track_index.last_track

		     - cmd.indexing.track_index.first_track+1;

    if ( cdrom->numtracks > SDL_MAX_TRACKS ) {

        cdrom->numtracks = SDL_MAX_TRACKS;

    }

    /* Read all the track TOC entries */

    for ( i=0; i<=cdrom->numtracks; ++i ) {

        if ( i == cdrom->numtracks ) {

            cdrom->track[i].id = 0xAA;;

        } else {

            cdrom->track[i].id = cmd.indexing.track_index.first_track+i;

        }

        entry.audio_cmds         = CD_GET_TRK_MSF;

	entry.indexing.track_msf.track = cdrom->track[i].id;

	if ( SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &entry) < 0 ) {

            break;

        } else {

            cdrom->track[i].type = 0;    /* don't know how to detect 0x04 data track */

            cdrom->track[i].offset = MSF_TO_FRAMES(

                entry.indexing.track_msf.mins,

                entry.indexing.track_msf.secs,

                entry.indexing.track_msf.frames);

            cdrom->track[i].length = 0;

            if ( i > 0 ) {

                cdrom->track[i-1].length = cdrom->track[i].offset

		                         - cdrom->track[i-1].offset;

            }

        }

    }

    if ( i == (cdrom->numtracks+1) ) {

        okay = 1;

    }

    return(okay ? 0 : -1);

}

/* Get CD-ROM status */

static CDstatus SDL_SYS_CDStatus(SDL_CD *cdrom, int *position)

{

    CDstatus            status;

    struct cd_audio_cmd cmd;

    cmd.audio_cmds = CD_INFO_AUDIO;

    if ( SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd) < 0 ) {

#ifdef DEBUG_CDROM

    fprintf(stderr, "ioctl failed in SDL_SYS_CDStatus (%s)\n", SDL_GetError());