Bochs/bochs/iodev/hdimage/cdrom.cc

306 lines
7.7 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id$
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2002-2021 The Bochs Project
//
// 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 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
/////////////////////////////////////////////////////////////////////////
// shared code for the low-level cdrom support
#include "bochs.h"
#include "cdrom.h"
#include <stdio.h>
#define LOG_THIS /* no SMF tricks here, not needed */
#define BX_CD_FRAMESIZE 2048
unsigned int bx_cdrom_count = 0;
cdrom_base_c::cdrom_base_c(const char *dev)
{
char prefix[6];
sprintf(prefix, "CD%d", ++bx_cdrom_count);
put(prefix);
fd = -1; // File descriptor not yet allocated
if (dev == NULL) {
path = NULL;
} else {
path = strdup(dev);
}
using_file = 0;
}
cdrom_base_c::~cdrom_base_c(void)
{
if (fd >= 0)
close(fd);
if (path)
free(path);
BX_DEBUG(("Exit"));
}
bool cdrom_base_c::insert_cdrom(const char *dev)
{
unsigned char buffer[BX_CD_FRAMESIZE];
ssize_t ret;
// Load CD-ROM. Returns 0 if CD is not ready.
if (dev != NULL) path = strdup(dev);
BX_INFO(("load cdrom with path='%s'", path));
// all platforms except win32
fd = open(path, O_RDONLY
#ifdef O_BINARY
| O_BINARY
#endif
);
if (fd < 0) {
BX_ERROR(("open cd failed for '%s': %s", path, strerror(errno)));
return 0;
}
// do fstat to determine if it's a file or a device, then set using_file.
struct stat stat_buf;
ret = fstat(fd, &stat_buf);
if (ret) {
BX_PANIC(("fstat cdrom file returned error: %s", strerror (errno)));
}
if (S_ISREG(stat_buf.st_mode)) {
using_file = 1;
BX_INFO(("Opening image file as a cd."));
} else {
using_file = 0;
BX_INFO(("Using direct access for cdrom."));
}
// I just see if I can read a sector to verify that a
// CD is in the drive and readable.
return read_block(buffer, 0, 2048);
}
void cdrom_base_c::eject_cdrom()
{
// Logically eject the CD. I suppose we could stick in
// some ioctl() calls to really eject the CD as well.
if (fd >= 0) {
close(fd);
fd = -1;
}
}
bool cdrom_base_c::read_toc(Bit8u* buf, int* length, bool msf, int start_track, int format)
{
unsigned i;
Bit32u blocks;
int len = 4;
switch (format) {
case 0:
// From atapi specs : start track can be 0-63, AA
if ((start_track > 1) && (start_track != 0xaa))
return 0;
buf[2] = 1;
buf[3] = 1;
if (start_track <= 1) {
buf[len++] = 0; // Reserved
buf[len++] = 0x14; // ADR, control
buf[len++] = 1; // Track number
buf[len++] = 0; // Reserved
// Start address
if (msf) {
buf[len++] = 0; // reserved
buf[len++] = 0; // minute
buf[len++] = 2; // second
buf[len++] = 0; // frame
} else {
buf[len++] = 0;
buf[len++] = 0;
buf[len++] = 0;
buf[len++] = 0; // logical sector 0
}
}
// Lead out track
buf[len++] = 0; // Reserved
buf[len++] = 0x16; // ADR, control
buf[len++] = 0xaa; // Track number
buf[len++] = 0; // Reserved
blocks = capacity();
// Start address
if (msf) {
buf[len++] = 0; // reserved
buf[len++] = (Bit8u)(((blocks + 150) / 75) / 60); // minute
buf[len++] = (Bit8u)(((blocks + 150) / 75) % 60); // second
buf[len++] = (Bit8u)((blocks + 150) % 75); // frame;
} else {
buf[len++] = (blocks >> 24) & 0xff;
buf[len++] = (blocks >> 16) & 0xff;
buf[len++] = (blocks >> 8) & 0xff;
buf[len++] = (blocks >> 0) & 0xff;
}
buf[0] = ((len-2) >> 8) & 0xff;
buf[1] = (len-2) & 0xff;
break;
case 1:
// multi session stuff - emulate a single session only
buf[0] = 0;
buf[1] = 0x0a;
buf[2] = 1;
buf[3] = 1;
for (i = 0; i < 8; i++)
buf[4+i] = 0;
len = 12;
break;
case 2:
// raw toc - emulate a single session only (ported from qemu)
buf[2] = 1;
buf[3] = 1;
for (i = 0; i < 4; i++) {
buf[len++] = 1;
buf[len++] = 0x14;
buf[len++] = 0;
if (i < 3) {
buf[len++] = 0xa0 + i;
} else {
buf[len++] = 1;
}
buf[len++] = 0;
buf[len++] = 0;
buf[len++] = 0;
if (i < 2) {
buf[len++] = 0;
buf[len++] = 1;
buf[len++] = 0;
buf[len++] = 0;
} else if (i == 2) {
blocks = capacity();
if (msf) {
buf[len++] = 0; // reserved
buf[len++] = (Bit8u)(((blocks + 150) / 75) / 60); // minute
buf[len++] = (Bit8u)(((blocks + 150) / 75) % 60); // second
buf[len++] = (Bit8u)((blocks + 150) % 75); // frame;
} else {
buf[len++] = (blocks >> 24) & 0xff;
buf[len++] = (blocks >> 16) & 0xff;
buf[len++] = (blocks >> 8) & 0xff;
buf[len++] = (blocks >> 0) & 0xff;
}
} else {
buf[len++] = 0;
buf[len++] = 0;
buf[len++] = 0;
buf[len++] = 0;
}
}
buf[0] = ((len-2) >> 8) & 0xff;
buf[1] = (len-2) & 0xff;
break;
default:
BX_PANIC(("cdrom: read_toc(): unknown format"));
return 0;
}
*length = len;
return 1;
}
bool BX_CPP_AttrRegparmN(3) cdrom_base_c::read_block(Bit8u* buf, Bit32u lba, int blocksize)
{
// Read a single block from the CD
off_t pos;
ssize_t n = 0;
Bit8u try_count = 3;
Bit8u* buf1;
if (blocksize == 2352) {
memset(buf, 0, 2352);
memset(buf+1, 0xff, 10);
Bit32u raw_block = lba + 150;
buf[12] = (raw_block / 75) / 60;
buf[13] = (raw_block / 75) % 60;
buf[14] = (raw_block % 75);
buf[15] = 0x01;
buf1 = buf + 16;
} else {
buf1 = buf;
}
do {
pos = lseek(fd, (off_t) lba * BX_CD_FRAMESIZE, SEEK_SET);
if (pos < 0) {
BX_PANIC(("cdrom: read_block: lseek returned error."));
} else {
n = read(fd, (char*) buf1, BX_CD_FRAMESIZE);
}
} while ((n != BX_CD_FRAMESIZE) && (--try_count > 0));
return (n == BX_CD_FRAMESIZE);
}
Bit32u cdrom_base_c::capacity()
{
// Return CD-ROM capacity. I believe you want to return
// the number of blocks of capacity the actual media has.
if (using_file) {
// return length of the image file
struct stat stat_buf;
int ret = fstat(fd, &stat_buf);
if (ret) {
BX_PANIC(("fstat on cdrom image returned err: %s", strerror(errno)));
}
if ((stat_buf.st_size % 2048) != 0) {
BX_ERROR(("expected cdrom image to be a multiple of 2048 bytes"));
}
return (Bit32u)(stat_buf.st_size / 2048);
} else {
BX_ERROR(("capacity: your OS is not supported yet"));
return 0;
}
}
bool cdrom_base_c::start_cdrom()
{
// Spin up the cdrom drive.
if (fd >= 0) {
BX_INFO(("start_cdrom: your OS is not supported yet"));
return 0; // OS not supported yet, return 0 always
}
return 0;
}
bool cdrom_base_c::seek(Bit32u lba)
{
unsigned char buffer[BX_CD_FRAMESIZE];
return read_block(buffer, lba, BX_CD_FRAMESIZE);
}