libburn/libburn/init.c

/* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */

#include <unistd.h>
#include <assert.h>
#include <stdio.h>
#include <signal.h>
#include <string.h>

#include "init.h"
#include "sg.h"
#include "error.h"
#include "libburn.h"
#include "drive.h"

/* ts A60825 : The storage location for back_hacks.h variables. */
#define BURN_BACK_HACKS_INIT 1
#include "back_hacks.h"

/* ts A60924 : a new message handling facility */
#include "libdax_msgs.h"
struct libdax_msgs *libdax_messenger= NULL;


int burn_running = 0;

/* ts A60813 : wether to use O_EXCL and/or O_NONBLOCK in libburn/sg.c */
int burn_sg_open_o_excl = 1;

/* O_NONBLOCK was hardcoded in enumerate_ata() which i hardly use.
   For enumerate_sg() it seems ok.
   So it should stay default mode until enumerate_ata() without O_NONBLOCK
   has been thoroughly tested. */
int burn_sg_open_o_nonblock = 1;

/* wether to take a busy drive as an error */
/* Caution: this is implemented by a rough hack and eventually leads
	    to unconditional abort of the process  */
int burn_sg_open_abort_busy = 0;


/* ts A61002 */

#include "cleanup.h"

/* Parameters for builtin abort handler */
static char abort_message_prefix[81] = {"libburn : "};
static pid_t abort_control_pid= 0;


/* ts A60925 : ticket 74 */
/** Create the messenger object for libburn. */
int burn_msgs_initialize(void)
{
	int ret;

	if(libdax_messenger == NULL) {
		ret = libdax_msgs_new(&libdax_messenger,0);
		if (ret <= 0)
			return 0;
	}
	libdax_msgs_set_severities(libdax_messenger, LIBDAX_MSGS_SEV_NEVER,
				   LIBDAX_MSGS_SEV_FATAL, "libburn: ", 0);
	return 1;
}

/* ts A60924 : ticket 74 : Added use of global libdax_messenger */
int burn_initialize(void)
{
	int ret;

	if (burn_running)
		return 1;
	ret = burn_msgs_initialize();
	if (ret <= 0)
		return 0;
	burn_running = 1;
	return 1;
}

void burn_finish(void)
{
	assert(burn_running);

	/* ts A61007 */
	/* burn_wait_all(); */
	if (!burn_drives_are_clear()) {
		libdax_msgs_submit(libdax_messenger, -1, 0x00020107,
			LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
			"Drive is busy on attempt to shut down library",
			0, 0);
		return;
	}

	/* ts A60904 : ticket 62, contribution by elmom : name addon "_all" */
	burn_drive_free_all();

	/* ts A60924 : ticket 74 */
	libdax_msgs_destroy(&libdax_messenger,0);

	burn_running = 0;
}


/* ts A60813 */
/** Set parameters for behavior on opening device files. To be called early
    after burn_initialize() and before any bus scan. But not mandatory at all.
    @param exclusive Try to open only devices which are not marked as busy
                     and try to mark them busy if opened sucessfully. (O_EXCL)
                     There are kernels which simply don't care about O_EXCL.
                     Some have it off, some have it on, some are switchable.
                     Values: 0=off, 1=on, 2=on,O_EXCL scsi siblings (sr,scd,st)
    @param blocking  Try to wait for drives which do not open immediately but
                     also do not return an error as well. (O_NONBLOCK)
                     This might stall indefinitely with /dev/hdX hard disks.
    @param abort_on_busy  Unconditionally abort process when a non blocking
                          exclusive opening attempt indicates a busy drive.
                          Use this only after thorough tests with your app.
    Parameter value 1 enables a feature, 0 disables.
    Default is (1,0,0). Have a good reason before you change it.
*/
void burn_preset_device_open(int exclusive, int blocking, int abort_on_busy)
{
	assert(burn_running);

	burn_sg_open_o_excl= exclusive;
	burn_sg_open_o_nonblock= !blocking;
	burn_sg_open_abort_busy= !!abort_on_busy;
}


/* ts A60924 : ticket 74 */
/** Control queueing and stderr printing of messages from libburn.
    Severity may be one of "NEVER", "FATAL", "SORRY", "WARNING", "HINT",
    "NOTE", "UPDATE", "DEBUG", "ALL".
    @param queue_severity Gives the minimum limit for messages to be queued.
                          Default: "NEVER". If you queue messages then you
                          must consume them by burn_msgs_obtain().
    @param print_severity Does the same for messages to be printed directly
                          to stderr.
    @param print_id       A text prefix to be printed before the message.
    @return               >0 for success, <=0 for error

*/
int burn_msgs_set_severities(char *queue_severity,
                             char *print_severity, char *print_id)
{
	int ret, queue_sevno, print_sevno;

	ret = libdax_msgs__text_to_sev(queue_severity, &queue_sevno, 0);
	if (ret <= 0)
		return 0;
	ret = libdax_msgs__text_to_sev(print_severity, &print_sevno, 0);
	if (ret <= 0)
		return 0;
	ret = libdax_msgs_set_severities(libdax_messenger, queue_sevno,
					 print_sevno, print_id, 0);
	if (ret <= 0)
		return 0;
	return 1;
}


/* ts A60924 : ticket 74 */
#define BURM_MSGS_MESSAGE_LEN 4096

/** Obtain the oldest pending libburn message from the queue which has at
    least the given minimum_severity. This message and any older message of
    lower severity will get discarded from the queue and is then lost forever.
    Severity may be one of "NEVER", "FATAL", "SORRY", "WARNING", "HINT",
    "NOTE", "UPDATE", "DEBUG", "ALL". To call with minimum_severity "NEVER"
    will discard the whole queue.
    @param error_code Will become a unique error code as liste in 
                      libburn/libdax_msgs.h
    @param msg_text   Must provide at least BURM_MSGS_MESSAGE_LEN bytes.
    @param os_errno   Will become the eventual errno related to the message
    @param severity   Will become the severity related to the message and
                      should provide at least 80 bytes.
    @return 1 if a matching item was found, 0 if not, <0 for severe errors
*/
int burn_msgs_obtain(char *minimum_severity,
                     int *error_code, char msg_text[], int *os_errno,
                     char severity[])
{
	int ret, minimum_sevno, sevno, priority;
	char *textpt, *sev_name;
	struct libdax_msgs_item *item = NULL;

	ret = libdax_msgs__text_to_sev(minimum_severity, &minimum_sevno, 0);
	if (ret <= 0)
		return 0;
	ret = libdax_msgs_obtain(libdax_messenger, &item, minimum_sevno,
				LIBDAX_MSGS_PRIO_ZERO, 0);
	if (ret <= 0)
		goto ex;
	ret = libdax_msgs_item_get_msg(item, error_code, &textpt, os_errno, 0);
	if (ret <= 0)
		goto ex;
	strncpy(msg_text, textpt, BURM_MSGS_MESSAGE_LEN-1);
	if(strlen(textpt) >= BURM_MSGS_MESSAGE_LEN)
		msg_text[BURM_MSGS_MESSAGE_LEN-1] = 0;

	severity[0]= 0;
	ret = libdax_msgs_item_get_rank(item, &sevno, &priority, 0);
	if(ret <= 0)
		goto ex;
	ret = libdax_msgs__sev_to_text(sevno, &sev_name, 0);
	if(ret <= 0)
		goto ex;
	strcpy(severity,sev_name);

	ret = 1;
ex:
	libdax_msgs_destroy_item(libdax_messenger, &item, 0);
	return ret;
}

int burn_builtin_abort_handler(void *handle, int signum, int flag)
{
	if(getpid() != abort_control_pid)
		return -2;
	Cleanup_set_handlers(NULL, NULL, 2);
	fprintf(stderr,"%sABORT : Trying to shut down drive and library\n",
		abort_message_prefix);
	fprintf(stderr,
		"%sABORT : Wait the normal burning time before any kill -9\n",
		abort_message_prefix);
	close(0); /* somehow stdin as input blocks abort until EOF */
	burn_abort(4440, burn_abort_pacifier, abort_message_prefix);
	fprintf(stderr,
	"\n%sABORT : Program done. Even if you do not see a shell prompt.\n\n",
		abort_message_prefix);
	return(1);
}

void burn_set_signal_handling(void *handle, burn_abort_handler_t handler,
			     int mode)
{
	if(handler == NULL && mode == 0) {
		handler = burn_builtin_abort_handler;
/*
		fprintf(stderr, "libburn_experimental: activated burn_builtin_abort_handler() with handle '%s'\n",(handle==NULL ? "libburn : " : (char *) handle));
*/

	}
	strcpy(abort_message_prefix, "libburn : ");
	if(handle != NULL)
		strncpy(abort_message_prefix, (char *) handle,
			sizeof(abort_message_prefix)-1);
	abort_message_prefix[sizeof(abort_message_prefix)-1] = 0;
	abort_control_pid= getpid();
	Cleanup_set_handlers(handle, (Cleanup_app_handler_T) handler, mode|4);
}