Experimental SCSI transport adapter via GNU libcdio

Makefile.am

@@ -201,8 +201,10 @@ EXTRA_DIST = \
 	cdrskin/cleanup.c \
 	libburn/os-freebsd.h \
 	libburn/os-linux.h \
+	libburn/os-libcdio.h \
 	libburn/sg-freebsd.c \
 	libburn/sg-linux.c \
+	libburn/sg-libcdio.c \
 	COPYING \
 	NEWS \
 	ChangeLog \

configure.ac

@@ -206,10 +206,30 @@ else
     LIBBURN_DVD_OBS_64K=
     echo "disabled write size default 64 KB on DVD and BD"
 fi
-dnl Avoid the need for libburn_libburn_la_CFLAGS in Makefile.am (ugly .o names)
-dnl ### AC_SUBST(LIBBURN_DVD_OBS_64K)
 CFLAGS="$CFLAGS $LIBBURN_DVD_OBS_64K"
 
+dnl ts A91218
+AC_ARG_ENABLE(libcdio,
+[  --enable-libcdio         Enable EXPERIMENTAL use of libcdio as system adapter, default=no],
+               , enable_libcdio=no)
+if test x$enable_libcdio = xyes; then
+dnl Check whether there is libcdio-devel and libcdio-runtime.
+dnl If not, erase this macro
+    LIBCDIO_DEF="-DLibburn_use_libcdiO" 
+dnl The empty yes case obviously causes -lacl to be linked
+    AC_CHECK_HEADER(cdio/cdio.h, AC_CHECK_LIB(cdio, cdio_open, , LIBCDIO_DEF= ), LIBCDIO_DEF= )
+else
+    LIBCDIO_DEF=
+fi
+if test x$LIBCDIO_DEF = x
+then
+    LIBCDIO_DEF=
+else
+    echo "enabled  EXPERIMENTAL use of libcdio as system adapter"
+    CFLAGS="$CFLAGS $LIBCDIO_DEF"
+fi
+
+
 
 dnl Add compiler-specific flags
 

libburn/os-libcdio.h

@@ -0,0 +1,62 @@
+
+/* os-dummy.h
+   Operating system specific libburn definitions and declarations. Included
+   by os.h in case of compilation for
+           Unknown POSIX like systems
+           with GNU libcdio MMC transport adapter sg-libcdio.c
+
+   Copyright (C) 2009 Thomas Schmitt <scdbackup@gmx.net>, provided under GPL
+*/
+
+
+/** List of all signals which shall be caught by signal handlers and trigger
+    a graceful abort of libburn. (See man 7 signal.)
+*/
+/* Once as system defined macros */
+#define BURN_OS_SIGNAL_MACRO_LIST \
+ SIGHUP, SIGINT, SIGQUIT, SIGILL, SIGABRT, \
+ SIGFPE, SIGSEGV, SIGPIPE, SIGALRM, SIGTERM, \
+ SIGUSR1, SIGUSR2, SIGXCPU, SIGTSTP, SIGTTIN, \
+ SIGTTOU
+
+/* Once as text 1:1 list of strings for messages and interpreters */
+#define BURN_OS_SIGNAL_NAME_LIST \
+ "SIGHUP", "SIGINT", "SIGQUIT", "SIGILL", "SIGABRT", \
+ "SIGFPE", "SIGSEGV", "SIGPIPE", "SIGALRM", "SIGTERM", \
+ "SIGUSR1", "SIGUSR2", "SIGXCPU", "SIGTSTP", "SIGTTIN", \
+ "SIGTTOU"
+
+/* The number of above list items */
+#define BURN_OS_SIGNAL_COUNT 16
+
+/** To list all signals which shall surely not be caught */
+#define BURN_OS_NON_SIGNAL_MACRO_LIST \
+SIGKILL, SIGCHLD, SIGSTOP
+
+/* The number of above list items */
+#define BURN_OS_NON_SIGNAL_COUNT 3
+
+
+/* The maximum size for a (SCSI) i/o transaction */
+/* Important : MUST be at least 32768 ! */
+#define BURN_OS_TRANSPORT_BUFFER_SIZE 65536
+
+
+/* To hold the position of the most recently delivered address from
+   device enumeration.
+*/
+struct burn_drive_enumerator_struct {
+	char **ppsz_cd_drives;
+	char **pos;
+};
+
+#define BURN_OS_DEFINE_DRIVE_ENUMERATOR_T \
+typedef struct burn_drive_enumerator_struct burn_drive_enumerator_t;
+
+
+/* The list of operating system dependent elements in struct burn_drive.
+   Usually they are initialized in  sg-*.c:enumerate_common().
+*/
+#define BURN_OS_TRANSPORT_DRIVE_ELEMENTS \
+	void *p_cdio; /* actually a pointer to CdIo_t */ \
+

libburn/os.h

@@ -13,6 +13,15 @@
    Operating system case distinction
 */
 
+
+#ifdef Libburn_use_libcdiO
+
+
+/* -------------------------- X/Open with GNU libcdio ---------------------- */
+#include "os-libcdio.h"
+
+
+#else
 #ifdef __FreeBSD__
 
 
@@ -37,6 +46,7 @@
 
 #endif /* ! __linux */
 #endif /* ! __FreeBSD__ */
+#endif /* ! Libburn_use_libcdiO */
 
 
 #endif /* ! BURN_OS_H_INCLUDED */

libburn/sg-freebsd-port.c

@@ -323,7 +323,7 @@ try_item:; /* This spaghetti loop keeps the number of tabs small  */
 int scsi_enumerate_drives(void)
 {
 	burn_drive_enumerator_t idx;
-	int initialize = 1;
+	int initialize = 1, ret;
 	char buf[64];
 
 	while(1) {
@@ -338,6 +338,7 @@ int scsi_enumerate_drives(void)
 				idx.result->target_lun);
 	}
 	sg_give_next_adr(&idx, buf, sizeof(buf), -1);
+	return 1;
 }
 
 
@@ -360,11 +361,12 @@ int sg_drive_is_open(struct burn_drive * d)
 */  
 int sg_grab(struct burn_drive *d)
 {
-	int count;
 	struct cam_device *cam;
 
-	if(d->cam != NULL)
+	if(d->cam != NULL) {
-		return 0;
+		d->released = 0;
+		return 1;
+	}
 
 	cam = cam_open_device(d->devname, O_RDWR);
 	if (cam == NULL) {
@@ -515,7 +517,7 @@ int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
                        int *target_no, int *lun_no)
 {
 	burn_drive_enumerator_t idx;
-	int initialize = 1;
+	int initialize = 1, ret;
 	char buf[64];
 	struct periph_match_result* result;
 
@@ -524,7 +526,7 @@ int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
 		initialize = 0;
 		if (ret <= 0)
 	break;
-		if (strcmp(adr, buf) != 0)
+		if (strcmp(path, buf) != 0)
 	continue;
 		result = &(idx->ccb.cdm.matches[i].result.periph_result);
 		*bus_no = result->path_id;
@@ -546,7 +548,7 @@ int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
 int sg_is_enumerable_adr(char* adr)
 {
 	burn_drive_enumerator_t idx;
-	int initialize = 1;
+	int initialize = 1, ret;
 	char buf[64];
 
 	while(1) {

libburn/sg-libcdio.c

@@ -0,0 +1,565 @@
+/* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */
+
+/*
+
+This is the main operating system dependent SCSI part of libburn. It implements
+the transport level aspects of SCSI control and command i/o.
+
+Present implementation: GNU libcdio , for X/Open compliant operating systems
+
+
+PORTING:
+
+Porting libburn typically will consist of adding a new operating system case
+to the following switcher files:
+  os.h    Operating system specific libburn definitions and declarations.
+  sg.c    Operating system dependent transport level modules.
+and of deriving the following system specific files from existing examples:
+  os-*.h  Included by os.h. You will need some general system knowledge
+          about signals and knowledge about the storage object needs of your
+          transport level module sg-*.c.
+
+  sg-*.c  This source module. You will need special system knowledge about
+          how to detect all potentially available drives, how to open them,
+          eventually how to exclusively reserve them, how to perform
+          SCSI transactions, how to inquire the (pseudo-)SCSI driver.
+          You will not need to care about CD burning, MMC or other high-level
+          SCSI aspects.
+
+Said sg-*.c operations are defined by a public function interface, which has
+to be implemented in a way that provides libburn with the desired services:
+ 
+sg_give_next_adr()      iterates over the set of potentially useful drive 
+                        address strings.
+
+scsi_enumerate_drives() brings all available, not-whitelist-banned, and
+                        accessible drives into libburn's list of drives.
+
+sg_drive_is_open()      tells wether libburn has the given drive in use.
+
+sg_grab()               opens the drive for SCSI commands and ensures
+                        undisturbed access.
+
+sg_release()            closes a drive opened by sg_grab()
+
+sg_issue_command()      sends a SCSI command to the drive, receives reply,
+                        and evaluates wether the command succeeded or shall
+                        be retried or finally failed.
+
+sg_obtain_scsi_adr()    tries to obtain SCSI address parameters.
+
+burn_os_stdio_capacity()  estimates the emulated media space of stdio-drives.
+
+burn_os_open_track_src()  opens a disk file in a way that allows best
+                        throughput with file reading and/or SCSI write command
+                        transmission.
+
+burn_os_alloc_buffer()  allocates a memory area that is suitable for file
+                        descriptors issued by burn_os_open_track_src().
+                        The buffer size may be rounded up for alignment
+                        reasons.
+
+burn_os_free_buffer()   delete a buffer obtained by burn_os_alloc_buffer().
+
+Porting hints are marked by the text "PORTING:".
+Send feedback to libburn-hackers@pykix.org .
+
+*/
+
+
+/** PORTING : ------- OS dependent headers and definitions ------ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <stdlib.h>
+
+#ifdef Libburn_os_has_statvfS
+#include <sys/statvfs.h>
+#endif /* Libburn_os_has_stavtfS */
+
+
+#include <cdio/cdio.h>
+#include <cdio/mmc.h>
+
+
+/** PORTING : ------ libburn portable headers and definitions ----- */
+
+#include "transport.h"
+#include "drive.h"
+#include "sg.h"
+#include "spc.h"
+/* collides with symbols of <cdio/mmc.h>
+ #include "mmc.h"
+*/
+#include "sbc.h"
+#include "debug.h"
+#include "toc.h"
+#include "util.h"
+
+#include "libdax_msgs.h"
+extern struct libdax_msgs *libdax_messenger;
+
+
+/* is in portable part of libburn */
+int burn_drive_is_banned(char *device_address);
+
+
+/* Whether to log SCSI commands:
+   bit0= log in /tmp/libburn_sg_command_log
+   bit1= log to stderr
+   bit2= flush every line
+*/
+extern int burn_sg_log_scsi;
+
+
+/* ------------------------------------------------------------------------ */
+/* PORTING: Private functions. Port only if needed by public functions      */
+/*          (Public functions are listed below)                             */
+/* ------------------------------------------------------------------------ */
+
+
+static int sg_close_drive(struct burn_drive * d)
+{
+	CdIo_t *p_cdio;
+
+	if (d->p_cdio != NULL) {
+		p_cdio = (CdIo_t *) d->p_cdio;
+		cdio_destroy(p_cdio);
+		d->p_cdio = NULL;
+	}
+	return 0;
+}
+
+
+/* ----------------------------------------------------------------------- */
+/* PORTING: Private functions which contain publicly needed functionality. */
+/*          Their portable part must be performed. So it is probably best  */
+/*          to replace the non-portable part and to call these functions   */
+/*          in your port, too.                                             */
+/* ----------------------------------------------------------------------- */
+
+
+/** Wraps a detected drive into libburn structures and hands it over to
+    libburn drive list.
+*/
+static void enumerate_common(char *fname, int bus_no, int host_no,
+			     int channel_no, int target_no, int lun_no)
+{
+	int ret;
+	struct burn_drive out;
+
+	/* General libburn drive setup */
+	burn_setup_drive(&out, fname);
+
+	/* This transport adapter uses SCSI-family commands and models
+	   (seems the adapter would know better than its boss, if ever) */
+	ret = burn_scsi_setup_drive(&out, bus_no, host_no, channel_no,
+                                 target_no, lun_no, 0);
+        if (ret <= 0)
+                return;
+
+	/* PORTING: ------------------- non portable part --------------- */
+
+	/* Transport adapter is libcdio */
+	/* Adapter specific handles and data */
+	out.p_cdio = NULL;
+
+	/* PORTING: ---------------- end of non portable part ------------ */
+
+	/* Adapter specific functions with standardized names */
+	out.grab = sg_grab;
+	out.release = sg_release;
+	out.drive_is_open = sg_drive_is_open;
+	out.issue_command = sg_issue_command;
+	/* Finally register drive and inquire drive information */
+	burn_drive_finish_enum(&out);
+}
+
+
+/* ------------------------------------------------------------------------ */
+/* PORTING:           Public functions. These MUST be ported.               */
+/* ------------------------------------------------------------------------ */
+
+
+/** Returns the next index number and the next enumerated drive address.
+    The enumeration has to cover all available and accessible drives. It is
+    allowed to return addresses of drives which are not available but under
+    some (even exotic) circumstances could be available. It is on the other
+    hand allowed, only to hand out addresses which can really be used right
+    in the moment of this call. (This implementation chooses the latter.)
+    @param idx An opaque handle. Make no own theories about it.
+    @param adr Takes the reply
+    @param adr_size Gives maximum size of reply including final 0
+    @param initialize  1 = start new,
+                       0 = continue, use no other values for now
+                      -1 = finish
+    @return 1 = reply is a valid address , 0 = no further address available
+           -1 = severe error (e.g. adr_size too small)
+*/
+int sg_give_next_adr(burn_drive_enumerator_t *idx,
+		     char adr[], int adr_size, int initialize)
+{
+	if (initialize == 1) {
+		idx->pos = idx->ppsz_cd_drives =
+					cdio_get_devices(DRIVER_DEVICE);
+		if (idx->ppsz_cd_drives == NULL)
+			return 0;
+	} else if (initialize == -1) {
+		if (*(idx->ppsz_cd_drives) != NULL)
+			cdio_free_device_list(idx->ppsz_cd_drives);
+		idx->ppsz_cd_drives = NULL;
+	}
+	if (idx->pos == NULL)
+		return 0;
+	if (*(idx->pos) == NULL)
+		return 0;
+	if (strlen(*(idx->pos)) >= adr_size)
+		return -1;
+	strcpy(adr, *(idx->pos));
+	(idx->pos)++;
+	return 1;
+}
+
+
+/** Brings all available, not-whitelist-banned, and accessible drives into
+    libburn's list of drives.
+*/
+int scsi_enumerate_drives(void)
+{
+	burn_drive_enumerator_t idx;
+	int initialize = 1, ret;
+	char buf[64];
+
+	while(1) {
+		ret = sg_give_next_adr(&idx, buf, sizeof(buf), initialize);
+		initialize = 0;
+		if (ret <= 0)
+	break;
+		if (burn_drive_is_banned(buf))
+	continue; 
+
+		/* >>> try to obtain bus,host,channel,target,lun */;
+
+		enumerate_common(buf, -1, -1, -1, -1, -1);
+	}
+	sg_give_next_adr(&idx, buf, sizeof(buf), -1);
+	return 1;
+}
+
+
+/** Tells wether libburn has the given drive in use or exclusively reserved.
+    If it is "open" then libburn will eventually call sg_release() on it when
+    it is time to give up usage resp. reservation.
+*/
+/** Published as burn_drive.drive_is_open() */
+int sg_drive_is_open(struct burn_drive * d)
+{
+	return (d->p_cdio != NULL);
+}
+
+
+/** Opens the drive for SCSI commands and - if burn activities are prone
+    to external interference on your system - obtains an exclusive access lock
+    on the drive. (Note: this is not physical tray locking.)
+    A drive that has been opened with sg_grab() will eventually be handed
+    over to sg_release() for closing and unreserving. 
+*/  
+int sg_grab(struct burn_drive *d)
+{
+	CdIo_t *p_cdio;
+
+	if(d->p_cdio != NULL) {
+		d->released = 0;
+		return 1;
+	}
+	p_cdio = cdio_open(d->devname, DRIVER_DEVICE);
+
+	if (p_cdio == NULL) {
+		libdax_msgs_submit(libdax_messenger, d->global_index,
+			0x00020003,
+			LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
+			"Could not grab drive", 0/*os_errno*/, 0);
+		return 0;
+	}
+	d->p_cdio = p_cdio;
+	d->released = 0;
+	return 1;
+}
+
+
+/** PORTING: Is mainly about the call to sg_close_drive() and whether it
+             implements the demanded functionality.
+*/
+/** Gives up the drive for SCSI commands and releases eventual access locks.
+    (Note: this is not physical tray locking.) 
+*/
+int sg_release(struct burn_drive *d)
+{
+	if (d->p_cdio == NULL) {
+		burn_print(1, "release an ungrabbed drive.  die\n");
+		return 0;
+	}
+	sg_close_drive(d);
+	return 0;
+}
+
+
+/** Sends a SCSI command to the drive, receives reply and evaluates wether
+    the command succeeded or shall be retried or finally failed.
+    Returned SCSI errors shall not lead to a return value indicating failure.
+    The callers get notified by c->error. An SCSI failure which leads not to
+    a retry shall be notified via scsi_notify_error().
+    The Libburn_log_sg_commandS facility might be of help when problems with
+    a drive have to be examined. It shall stay disabled for normal use.
+    @return: 1 success , <=0 failure
+*/
+int sg_issue_command(struct burn_drive *d, struct command *c)
+{
+	int i_status;
+	unsigned int dxfer_len;
+        static FILE *fp = NULL;
+	mmc_cdb_t cdb = {{0, }};
+	cdio_mmc_direction_t e_direction;
+	CdIo_t *p_cdio;
+	char msg[160];
+
+	c->error = 0;
+	if (d->p_cdio == NULL) {
+		return 0;
+	}
+	p_cdio = (CdIo_t *) d->p_cdio;
+        if (burn_sg_log_scsi & 1) {
+                if (fp == NULL) {
+                        fp= fopen("/tmp/libburn_sg_command_log", "a");
+                        fprintf(fp,
+                            "\n-----------------------------------------\n");
+                }
+        }
+        if (burn_sg_log_scsi & 3)
+                scsi_log_cmd(c,fp,0);
+
+	memcpy(cdb.field, c->opcode, c->oplen);
+	if (c->dir == TO_DRIVE) {
+		dxfer_len = c->page->bytes;
+		e_direction = SCSI_MMC_DATA_WRITE;
+	} else if (c->dir == FROM_DRIVE) {
+		if (c->dxfer_len >= 0)
+			dxfer_len = c->dxfer_len;
+		else
+			dxfer_len = BUFFER_SIZE;
+		e_direction = SCSI_MMC_DATA_READ;
+		/* touch page so we can use valgrind */
+		memset(c->page->data, 0, BUFFER_SIZE);
+	} else {
+		dxfer_len = 0;
+#ifdef SCSI_MMC_HAS_DIR_NONE
+		e_direction = SCSI_MMC_DATA_NONE;
+#else
+		e_direction = SCSI_MMC_DATA_READ;
+#endif
+	}
+		
+	/* >>> longer timeout , sg-linux has 200 s */
+
+	/* >>> retry-loop */
+
+		i_status = mmc_run_cmd(p_cdio, 10000, &cdb, e_direction,
+				 	dxfer_len, c->page->data);
+	
+		if (i_status == 0)
+			return 1;
+
+		/* >>> One would need to get info about the nature of failure
+		       SCSI SK,ASC,ASCQ would be nice.
+		       One would need to distinguish between drive error and
+		       transport error.
+		 */;
+
+/* This is for failure of the transport mechanism itself:
+
+			libdax_msgs_submit(libdax_messenger,
+				d->global_index, 0x0002010c,
+				LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
+				"Failed to transfer command to drive",
+				errno, 0);
+			sg_close_drive(d);
+			d->released = 1;
+			d->busy = BURN_DRIVE_IDLE;
+*/
+
+	/* >>> end retry-loop */
+
+
+	if (c->opcode[0] != 0x00) {
+		sprintf(msg, "SCSI command %2.2Xh failed",
+			(unsigned int) c->opcode[0]);
+		libdax_msgs_submit(libdax_messenger,
+			d->global_index, 0x0002010f,
+			LIBDAX_MSGS_SEV_DEBUG, LIBDAX_MSGS_PRIO_HIGH,
+			msg, errno, 0);
+	}
+
+	/* 2 04 00 LOGICAL UNIT NOT READY, CAUSE NOT REPORTABLE */
+	c->sense[2] = 0x02;
+	c->sense[12] = 0x04;
+	c->sense[13] = 0x00;
+
+	c->error = 1;
+	return -1;
+}
+
+
+/** Tries to obtain SCSI address parameters.
+    @return  1 is success , 0 is failure
+*/
+int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
+                       int *target_no, int *lun_no)
+{
+
+	/* >>> any chance to get them from libcdio ? */;
+
+	*bus_no = *host_no = *channel_no = *target_no = *lun_no = -1;
+	return (0);
+}
+
+
+/** Tells wether a text is a persistent address as listed by the enumeration
+    functions.
+*/
+int sg_is_enumerable_adr(char* adr)
+{
+	burn_drive_enumerator_t idx;
+	int initialize = 1, ret;
+	char buf[64];
+
+	while(1) {
+		ret = sg_give_next_adr(&idx, buf, sizeof(buf), initialize);
+		initialize = 0;
+		if (ret <= 0)
+	break;
+		if (strcmp(adr, buf) == 0) {
+			sg_give_next_adr(&idx, buf, sizeof(buf), -1);
+			return 1;
+		}
+	}
+	sg_give_next_adr(&idx, buf, sizeof(buf), -1);
+	return (0);
+}
+
+
+/** Estimate the potential payload capacity of a file address.
+    @param path  The address of the file to be examined. If it does not
+                 exist yet, then the directory will be inquired.
+    @param bytes The pointed value gets modified, but only if an estimation is
+                 possible.
+    @return      -2 = cannot perform necessary operations on file object
+                 -1 = neither path nor dirname of path exist
+                  0 = could not estimate size capacity of file object
+                  1 = estimation has been made, bytes was set
+*/
+int burn_os_stdio_capacity(char *path, off_t *bytes)
+{
+	struct stat stbuf;
+
+#ifdef Libburn_os_has_statvfS
+	struct statvfs vfsbuf;
+#endif
+
+	char testpath[4096], *cpt;
+	long blocks;
+	off_t add_size = 0;
+
+	testpath[0] = 0;
+	blocks = *bytes / 512;
+	if (stat(path, &stbuf) == -1) {
+		strcpy(testpath, path);
+		cpt = strrchr(testpath, '/');
+		if(cpt == NULL)
+			strcpy(testpath, ".");
+		else if(cpt == testpath)
+			testpath[1] = 0;
+		else
+			*cpt = 0;
+		if (stat(testpath, &stbuf) == -1)
+			return -1;
+
+#ifdef Libburn_if_this_was_linuX
+
+	} else if(S_ISBLK(stbuf.st_mode)) {
+		fd = open(path, open_mode);
+		if (fd == -1)
+			return -2;
+		ret = ioctl(fd, BLKGETSIZE, &blocks);
+		close(fd);
+		if (ret == -1)
+			return -2;
+		*bytes = ((off_t) blocks) * (off_t) 512;
+
+#endif /* Libburn_if_this_was_linuX */
+
+	} else if(S_ISREG(stbuf.st_mode)) {
+		add_size = stbuf.st_blocks * (off_t) 512;
+		strcpy(testpath, path);
+	} else
+		return 0;
+
+	if (testpath[0]) {	
+
+#ifdef Libburn_os_has_statvfS
+
+		if (statvfs(testpath, &vfsbuf) == -1)
+			return -2;
+		*bytes = add_size + ((off_t) vfsbuf.f_bsize) *
+						(off_t) vfsbuf.f_bavail;
+
+#else /* Libburn_os_has_statvfS */
+
+		return 0;
+
+#endif /* ! Libburn_os_has_stavtfS */
+
+	}
+	return 1;
+}
+
+
+/* ts A91122 : an interface to open(O_DIRECT) or similar OS tricks. */
+
+#ifdef Libburn_read_o_direcT
+
+	/* No special O_DIRECT-like precautions are implemented here */
+
+#endif /* Libburn_read_o_direcT */
+
+
+int burn_os_open_track_src(char *path, int open_flags, int flag)
+{
+	int fd;
+
+	fd = open(path, open_flags);
+	return fd;
+}
+
+
+void *burn_os_alloc_buffer(size_t amount, int flag)
+{
+	void *buf = NULL;
+
+	buf = calloc(1, amount);
+	return buf;
+}
+
+
+int burn_os_free_buffer(void *buffer, size_t amount, int flag)
+{
+	if (buffer == NULL)
+		return 0;
+	free(buffer);
+	return 1;
+}
+

libburn/sg.c

@@ -5,6 +5,11 @@
 */
 
 
+#ifdef Libburn_use_libcdiO
+
+#include "sg-libcdio.c"
+
+#else
 #ifdef __FreeBSD__
 
 #include "sg-freebsd.c"
@@ -38,4 +43,5 @@ static int intentional_compiler_warning(void)
 
 #endif /* ! __linux */
 #endif /* ! __FreeBSD__ */
+#endif /* ! Libburn_use_libcdiO */