New API function burn_random_access_write()

cdrskin/cdrskin_timestamp.h

@@ -1 +1 @@
-#define Cdrskin_timestamP "2007.08.11.075330"
+#define Cdrskin_timestamP "2007.08.11.202027"

libburn/libburn.h

@@ -1427,11 +1427,14 @@ void burn_write_opts_set_multi(struct burn_write_opts *opts, int multi);
 
 /* ts A61222 */
 /** Sets a start address for writing to media and write modes which allow to
-    choose this address at all (DVD+RW, DVD-RAM, formatted DVD-RW only for
+    choose this address at all (for now: DVD+RW, DVD-RAM, formatted DVD-RW).
     now). The address is given in bytes. If it is not -1 then a write run
     will fail if choice of start address is not supported or if the block
     alignment of the address is not suitable for media and write mode.
-    (Alignment to 32 kB blocks is advised with DVD media.)
+    Alignment to 32 kB blocks is supposed to be safe with DVD media.
+    Call burn_disc_get_multi_caps() can obtain the necessary media info. See
+    resulting struct burn_multi_caps elements .start_adr , .start_alignment ,
+    .start_range_low , .start_range_high .
     @param opts The write opts to change
     @param value The address in bytes (-1 = start at default address)
 */
@@ -1788,7 +1791,7 @@ int burn_msgs_obtain(char *minimum_severity,
 
 
 /* ts A61002 */
-/* The prototype of a handler function suitable for burn_set_abort_handling().
+/** The prototype of a handler function suitable for burn_set_abort_handling().
     Such a function has to return -2 if it does not want the process to
     exit with value 1.
 */
@@ -1810,6 +1813,34 @@ typedef int (*burn_abort_handler_t)(void *handle, int signum, int flag);
 void burn_set_signal_handling(void *handle, burn_abort_handler_t handler, 
 			     int mode);
 
+/* ts A70811 */
+/** Circumvent usual libburn session processing and rather write data without
+    preparations or finalizing. This will work only with overwriteable media
+    which are also suitable for burn_write_opts_set_start_byte(). The same
+    address alignment restrictions as with this function apply. I.e. for DVD
+    it is best to align to 32 KiB blocks (= 16 LBA units). The amount of data
+    to be written is subject to the same media dependent alignment rules.
+    Again, 32 KiB is most safe.
+    Call burn_disc_get_multi_caps() can obtain the necessary media info. See
+    resulting struct burn_multi_caps elements .start_adr , .start_alignment ,
+    .start_range_low , .start_range_high .
+    Other than burn_disc_write() this is a synchronous call which returns
+    only after the write transaction has ended (sucessfully or not). So it is
+    wise not to transfer giant amounts of data in a single call.
+    @param d            The drive to which to write 
+    @param byte_address The start address of the write in byte
+                        (1 LBA unit = 2048 bytes) (do respect media alignment)
+    @param data         The bytes to be written
+    @param data_count   The number of those bytes (do respect media alignment)
+                        data_count == 0 is permitted (e.g. to flush the
+                        drive buffer without further data transfer).
+    @param flag         Bitfield for control purposes:
+                        bit0 = flush the drive buffer after eventual writing
+    @return 1=sucessful , <=0 : number of tranfered bytes * -1
+*/
+int burn_random_access_write(struct burn_drive *d, off_t byte_address,
+                             char *data, off_t data_count, int flag);
+
 #ifndef DOXYGEN
 
 BURN_END_DECLS

libburn/libdax_msgs.h

@@ -371,6 +371,8 @@ Range "scdbackup"          :  0x00020000 to 0x0002ffff
  0x0002013d (DEBUG,LOW)    = Waiting for free buffer space takes long time
  0x0002013e (SORRY,HIGH)   = Timeout with waiting for free buffer. Now disabled
  0x0002013f (DEBUG,LOW)    = Reporting total time spent with waiting for buffer
+ 0x00020140 (FATAL,HIGH)   = Drive is busy on attempt to write random access
+ 0x00020141 (SORRY,HIGH)   = Write data count not properly aligned
 
 
  libdax_audioxtr:

libburn/write.c

@@ -1523,7 +1523,7 @@ int burn_dvd_write_sync(struct burn_write_opts *o,
 			sprintf(msg,
 			  "Write start address not properly aligned to 2048");
 			libdax_msgs_submit(libdax_messenger, d->global_index,
-				0x00020125,
+				0x00020126,
 				LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
 				msg, 0, 0);
 			goto early_failure;
@@ -1553,7 +1553,7 @@ int burn_dvd_write_sync(struct burn_write_opts *o,
 			sprintf(msg,
 			  "Write start address not properly aligned to 32K");
 			libdax_msgs_submit(libdax_messenger, d->global_index,
-				0x00020125,
+				0x00020126,
 				LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
 				msg, 0, 0);
 			goto early_failure;
@@ -1636,7 +1636,7 @@ int burn_dvd_write_sync(struct burn_write_opts *o,
 		if (o->start_byte >= 0) {
 			sprintf(msg, "Write start address not supported");
 			libdax_msgs_submit(libdax_messenger, d->global_index,
-				0x00020124,
+				0x00020125,
 				LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
 				msg, 0, 0);
 			goto early_failure;
@@ -1969,3 +1969,82 @@ fail_wo_sync:;
 	d->cancel = 1;
 	d->busy = BURN_DRIVE_IDLE;
 }
+
+
+int burn_random_access_write(struct burn_drive *d, off_t byte_address,
+                             char *data, off_t data_count, int flag)
+{
+	int alignment = 0, start, upto, chunksize, err;
+	char msg[81], *rpt;
+	struct buffer buf;
+
+	if (d->current_profile == 0x12) /* DVD-RAM */
+		alignment = 2 * 1024;
+        if (d->current_profile == 0x13) /* DVD-RW restricted overwrite */
+		alignment = 32 * 1024;
+	if (d->current_profile == 0x1a) /* DVD+RW */
+		alignment = 2 * 1024;
+	if (alignment == 0) {
+		sprintf(msg, "Write start address not supported");
+		libdax_msgs_submit(libdax_messenger, d->global_index,
+			0x00020125,
+			LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
+			"Write start address not supported", 0, 0);
+		return 0;
+	}
+	if ((byte_address % alignment) != 0) {
+		sprintf(msg,
+			"Write start address not properly aligned (%d bytes)",
+			alignment);
+		libdax_msgs_submit(libdax_messenger, d->global_index,
+			0x00020126,
+			LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
+			msg, 0, 0);
+		return 0;
+	}
+	if ((data_count % alignment) != 0) {
+		sprintf(msg,
+			"Write data count not properly aligned (%ld bytes)",
+			(long) alignment);
+		libdax_msgs_submit(libdax_messenger, d->global_index,
+			0x00020141,
+			LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
+			msg, 0, 0);
+		return 0;
+	}
+
+	if (d->busy != BURN_DRIVE_IDLE) {
+		libdax_msgs_submit(libdax_messenger,
+			d->global_index, 0x00020140,
+			LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
+			"Drive is busy on attempt to write random access",0,0);
+		return 0;
+	}
+	d->busy = BURN_DRIVE_WRITING;
+	d->buffer = &buf;
+
+	start = byte_address / 2048;
+	upto = start + data_count / 2048;
+	rpt = data;
+	for (; start < upto; start += 16) {
+		chunksize = upto - start;
+		if (chunksize > 16)
+			chunksize = 16;
+		d->buffer->bytes = chunksize * 2048;
+		memcpy(d->buffer->data, rpt, d->buffer->bytes);
+		rpt += d->buffer->bytes;
+		d->buffer->sectors = chunksize;
+		d->nwa = start;
+		err = d->write(d, d->nwa, d->buffer);
+		if (err == BE_CANCELLED) {
+			d->busy = BURN_DRIVE_IDLE;
+			return (-(start * 2048 - byte_address));
+		}
+	}
+
+	if (flag & 1)
+		d->sync_cache(d);
+	d->busy = BURN_DRIVE_IDLE;
+	return(1);
+}
+