scan.c

关于dvb的应用程序代码

		warning("truncated section (PID 0x%04x, lenght %d)",
			s->pid, section_length + 9);
		return 0;
	}

	if (!get_bit(s->section_done, section_number)) {
		set_bit (s->section_done, section_number);

		debug("pid 0x%02x tid 0x%02x table_id_ext 0x%04x, "
		    "%i/%i (version %i)\n",
		    s->pid, table_id, table_id_ext, section_number,
		    last_section_number, section_version_number);

		switch (table_id) {
		case 0x00:
			verbose("PAT\n");
			parse_pat (buf, section_length, table_id_ext);
			break;

		case 0x02:
			verbose("PMT 0x%04x for service 0x%04x\n", s->pid, table_id_ext);
			parse_pmt (buf, section_length, table_id_ext);
			break;

		case 0x41:
			verbose("////////////////////////////////////////////// NIT other\n");
		case 0x40:
			verbose("NIT (%s TS)\n", table_id == 0x40 ? "actual":"other");
			parse_nit (buf, section_length, table_id_ext);
			break;

		case 0x42:
		case 0x46:
			verbose("SDT (%s TS)\n", table_id == 0x42 ? "actual":"other");
			parse_sdt (buf, section_length, table_id_ext);
			break;

		case 0xc8:
		case 0xc9:
			verbose("ATSC VCT\n");
			parse_psip_vct(buf, section_length, table_id, table_id_ext);
			break;
		default:
			;
		};

		for (i = 0; i <= last_section_number; i++)
			if (get_bit (s->section_done, i) == 0)
				break;

		if (i > last_section_number)
			s->sectionfilter_done = 1;
	}

	if (s->segmented) {
		/* always wait for timeout; this is because we don't now how
		 * many segments there are
		 */
		return 0;
	}
	else if (s->sectionfilter_done)
		return 1;

	return 0;
}


static int read_sections (struct section_buf *s)
{
	int section_length, count;

	if (s->sectionfilter_done && !s->segmented)
		return 1;

	/* the section filter API guarantess that we get one full section
	 * per read(), provided that the buffer is large enough (it is)
	 */
	if (((count = read (s->fd, s->buf, sizeof(s->buf))) < 0) && errno == EOVERFLOW)
		count = read (s->fd, s->buf, sizeof(s->buf));
	if (count < 0) {
		errorn("read_sections: read error");
		return -1;
	}

	if (count < 4)
		return -1;

	section_length = ((s->buf[1] & 0x0f) << 8) | s->buf[2];

	if (count != section_length + 3)
		return -1;

	if (parse_section(s) == 1)
		return 1;

	return 0;
}


static LIST_HEAD(running_filters);
static LIST_HEAD(waiting_filters);
static int n_running;
#define MAX_RUNNING 27
static struct pollfd poll_fds[MAX_RUNNING];
static struct section_buf* poll_section_bufs[MAX_RUNNING];


static void setup_filter (struct section_buf* s, const char *dmx_devname,
			  int pid, int tid, int tid_ext,
			  int run_once, int segmented, int timeout)
{
	memset (s, 0, sizeof(struct section_buf));

	s->fd = -1;
	s->dmx_devname = dmx_devname;
	s->pid = pid;
	s->table_id = tid;

	s->run_once = run_once;
	s->segmented = segmented;

	if (long_timeout)
		s->timeout = 5 * timeout;
	else
		s->timeout = timeout;

	s->table_id_ext = tid_ext;
	s->section_version_number = -1;

	INIT_LIST_HEAD (&s->list);
}

static void update_poll_fds(void)
{
	struct list_head *p;
	struct section_buf* s;
	int i;

	memset(poll_section_bufs, 0, sizeof(poll_section_bufs));
	for (i = 0; i < MAX_RUNNING; i++)
		poll_fds[i].fd = -1;
	i = 0;
	list_for_each (p, &running_filters) {
		if (i >= MAX_RUNNING)
			fatal("too many poll_fds\n");
		s = list_entry (p, struct section_buf, list);
		if (s->fd == -1)
			fatal("s->fd == -1 on running_filters\n");
		verbosedebug("poll fd %d\n", s->fd);
		poll_fds[i].fd = s->fd;
		poll_fds[i].events = POLLIN;
		poll_fds[i].revents = 0;
		poll_section_bufs[i] = s;
		i++;
	}
	if (i != n_running)
		fatal("n_running is hosed\n");
}

static int start_filter (struct section_buf* s)
{
	struct dmx_sct_filter_params f;

	if (n_running >= MAX_RUNNING)
		goto err0;
	if ((s->fd = open (s->dmx_devname, O_RDWR | O_NONBLOCK)) < 0)
		goto err0;

	verbosedebug("start filter pid 0x%04x table_id 0x%02x\n", s->pid, s->table_id);

	memset(&f, 0, sizeof(f));

	f.pid = (uint16_t) s->pid;

	if (s->table_id < 0x100 && s->table_id > 0) {
		f.filter.filter[0] = (uint8_t) s->table_id;
		f.filter.mask[0]   = 0xff;
	}
	if (s->table_id_ext < 0x10000 && s->table_id_ext > 0) {
		f.filter.filter[1] = (uint8_t) ((s->table_id_ext >> 8) & 0xff);
		f.filter.filter[2] = (uint8_t) (s->table_id_ext & 0xff);
		f.filter.mask[1] = 0xff;
		f.filter.mask[2] = 0xff;
	}

	f.timeout = 0;
	f.flags = DMX_IMMEDIATE_START | DMX_CHECK_CRC;

	if (ioctl(s->fd, DMX_SET_FILTER, &f) == -1) {
		errorn ("ioctl DMX_SET_FILTER failed");
		goto err1;
	}

	s->sectionfilter_done = 0;
	time(&s->start_time);

	list_del_init (&s->list);  /* might be in waiting filter list */
	list_add (&s->list, &running_filters);

	n_running++;
	update_poll_fds();

	return 0;

err1:
	ioctl (s->fd, DMX_STOP);
	close (s->fd);
err0:
	return -1;
}


static void stop_filter (struct section_buf *s)
{
	verbosedebug("stop filter pid 0x%04x\n", s->pid);
	ioctl (s->fd, DMX_STOP);
	close (s->fd);
	s->fd = -1;
	list_del (&s->list);
	s->running_time += time(NULL) - s->start_time;

	n_running--;
	update_poll_fds();
}


static void add_filter (struct section_buf *s)
{
	verbosedebug("add filter pid 0x%04x\n", s->pid);
	if (start_filter (s))
		list_add_tail (&s->list, &waiting_filters);
}


static void remove_filter (struct section_buf *s)
{
	verbosedebug("remove filter pid 0x%04x\n", s->pid);
	stop_filter (s);

	while (!list_empty(&waiting_filters)) {
		struct list_head *next = waiting_filters.next;
		s = list_entry (next, struct section_buf, list);
		if (start_filter (s))
			break;
	};
}


static void read_filters (void)
{
	struct section_buf *s;
	int i, n, done;

	n = poll(poll_fds, n_running, 1000);
	if (n == -1)
		errorn("poll");

	for (i = 0; i < n_running; i++) {
		s = poll_section_bufs[i];
		if (!s)
			fatal("poll_section_bufs[%d] is NULL\n", i);
		if (poll_fds[i].revents)
			done = read_sections (s) == 1;
		else
			done = 0; /* timeout */
		if (done || time(NULL) > s->start_time + s->timeout) {
			if (s->run_once) {
				if (done)
					verbosedebug("filter done pid 0x%04x\n", s->pid);
				else
					warning("filter timeout pid 0x%04x\n", s->pid);
				remove_filter (s);
			}
		}
	}
}


static int mem_is_zero (const void *mem, int size)
{
	const char *p = mem;
	int i;

	for (i=0; i<size; i++) {
		if (p[i] != 0x00)
			return 0;
	}

	return 1;
}


static int switch_pos = 0;

static int __tune_to_transponder (int frontend_fd, struct transponder *t)
{
	struct dvb_frontend_parameters p;
	fe_status_t s;
	int i;

	current_tp = t;

	if (mem_is_zero (&t->param, sizeof(struct dvb_frontend_parameters)))
		return -1;

	memcpy (&p, &t->param, sizeof(struct dvb_frontend_parameters));

	if (verbosity >= 1) {
		dprintf(1, ">>> tune to: ");
		dump_dvb_parameters (stderr, t);
		if (t->last_tuning_failed)
			dprintf(1, " (tuning failed)");
		dprintf(1, "\n");
	}

	if (t->type == FE_QPSK) {
		int hiband = 0;

		if (lnb_type.switch_val && lnb_type.high_val &&
			p.frequency >= lnb_type.switch_val)
			hiband = 1;

		setup_switch (frontend_fd,
			      switch_pos,
			      t->polarisation == POLARISATION_VERTICAL ? 0 : 1,
			      hiband);
		usleep(50000);
		if (hiband)
			p.frequency = abs(p.frequency - lnb_type.high_val);
		else
			p.frequency = abs(p.frequency - lnb_type.low_val);
	}

	if (ioctl(frontend_fd, FE_SET_FRONTEND, &p) == -1) {
		errorn("Setting frontend parameters failed");
		return -1;
	}

	for (i = 0; i < 10; i++) {
		usleep (200000);

		if (ioctl(frontend_fd, FE_READ_STATUS, &s) == -1) {
			errorn("FE_READ_STATUS failed");
			return -1;
		}

		verbose(">>> tuning status == 0x%02x\n", s);

		if (s & FE_HAS_LOCK) {
			t->last_tuning_failed = 0;
			return 0;
		}
	}

	warning(">>> tuning failed!!!\n");

	t->last_tuning_failed = 1;

	return -1;
}

static int tune_to_transponder (int frontend_fd, struct transponder *t)
{
	/* move TP from "new" to "scanned" list */
	list_del_init(&t->list);
	list_add_tail(&t->list, &scanned_transponders);
	t->scan_done = 1;

	if (t->type != fe_info.type) {
		warning("frontend type (%s) is not compatible with requested tuning type (%s)\n",
				fe_type2str(fe_info.type),fe_type2str(t->type));
		/* ignore cable descriptors in sat NIT and vice versa */
		t->last_tuning_failed = 1;
		return -1;
	}

	if (__tune_to_transponder (frontend_fd, t) == 0)
		return 0;

	return __tune_to_transponder (frontend_fd, t);
}


static int tune_to_next_transponder (int frontend_fd)
{
	struct list_head *pos, *tmp;
	struct transponder *t, *to;
	uint32_t freq;

	list_for_each_safe(pos, tmp, &new_transponders) {
		t = list_entry (pos, struct transponder, list);
retry:
		if (tune_to_transponder (frontend_fd, t) == 0)
			return 0;
next:
		if (t->other_frequency_flag && t->other_f && t->n_other_f) {
			/* check if the alternate freqeuncy is really new to us */
			freq = t->other_f[t->n_other_f - 1];
			t->n_other_f--;
			if (find_transponder(freq))
				goto next;

			/* remember tuning to the old frequency failed */
			to = calloc(1, sizeof(*to));
			to->param.frequency = t->param.frequency;
			to->wrong_frequency = 1;
			INIT_LIST_HEAD(&to->list);
			INIT_LIST_HEAD(&to->services);
			list_add_tail(&to->list, &scanned_transponders);
			copy_transponder(to, t);

			t->param.frequency = freq;
			info("retrying with f=%d\n", t->param.frequency);
			goto retry;
		}
	}
	return -1;
}

struct strtab {
	const char *str;
	int val;
};
static int str2enum(const char *str, const struct strtab *tab, int deflt)
{
	while (tab->str) {
		if (!strcmp(tab->str, str))
			return tab->val;
		tab++;
	}
	error("invalid enum value '%s'\n", str);
	return deflt;
}

static const char * enum2str(int v, const struct strtab *tab, const char *deflt)
{
	while (tab->str) {
		if (v == tab->val)
			return tab->str;
		tab++;
	}
	error("invalid enum value '%d'\n", v);
	return deflt;
}

static enum fe_code_rate str2fec(const char *fec)
{
	struct strtab fectab[] = {
		{ "NONE", FEC_NONE },
		{ "1/2",  FEC_1_2 },
		{ "2/3",  FEC_2_3 },
		{ "3/4",  FEC_3_4 },
		{ "4/5",  FEC_4_5 },
		{ "5/6",  FEC_5_6 },
		{ "6/7",  FEC_6_7 },
		{ "7/8",  FEC_7_8 },
		{ "8/9",  FEC_8_9 },
		{ "AUTO", FEC_AUTO },
		{ NULL, 0 }
	};
	return str2enum(fec, fectab, FEC_AUTO);
}

static enum fe_modulation str2qam(const char *qam)
{
	struct strtab qamtab[] = {
		{ "QPSK",   QPSK },
		{ "QAM16",  QAM_16 },
		{ "QAM32",  QAM_32 },
		{ "QAM64",  QAM_64 },
		{ "QAM128", QAM_128 },
		{ "QAM256", QAM_256 },
		{ "AUTO",   QAM_AUTO },
		{ "8VSB",   VSB_8 },
		{ "16VSB",  VSB_16 },
		{ NULL, 0 }
	};
	return str2enum(qam, qamtab, QAM_AUTO);
}

static enum fe_bandwidth str2bandwidth(const char *bw)
{
	struct strtab bwtab[] = {
		{ "8MHz", BANDWIDTH_8_MHZ },
		{ "7MHz", BANDWIDTH_7_MHZ },
		{ "6MHz", BANDWIDTH_6_MHZ },
		{ "AUTO", BANDWIDTH_AUTO },
		{ NULL, 0 }
	};
	return str2enum(bw, bwtab, BANDWIDTH_AUTO);
}

static enum fe_transmit_mode str2mode(const char *mode)
{
	struct strtab modetab[] = {
		{ "2k",   TRANSMISSION_MODE_2K },
		{ "8k",   TRANSMISSION_MODE_8K },
		{ "AUTO", TRANSMISSION_MODE_AUTO },
		{ NULL, 0 }
	};
	return str2enum(mode, modetab, TRANSMISSION_MODE_AUTO);
}

static enum fe_guard_interval str2guard(const char *guard)
{
	struct strtab guardtab[] = {
		{ "1/32", GUARD_INTERVAL_1_32 },
		{ "1/16", GUARD_INTERVAL_1_16 },
		{ "1/8",  GUARD_INTERVAL_1_8 },
		{ "1/4",  GUARD_INTERVAL_1_4 },
		{ "AUTO", GUARD_INTERVAL_AUTO },
		{ NULL, 0 }
	};
	return str2enum(guard, guardtab, GUARD_INTERVAL_AUTO);
}

static enum fe_hierarchy str2hier(const char *hier)
{
	struct strtab hiertab[] = {
		{ "NONE", HIERARCHY_NONE },
		{ "1",    HIERARCHY_1 },
		{ "2",    HIERARCHY_2 },
		{ "4",    HIERARCHY_4 },
		{ "AUTO", HIERARCHY_AUTO },
		{ NULL, 0 }
	};
	return str2enum(hier, hiertab, HIERARCHY_AUTO);
}

static const char * fe_type2str(fe_type_t t)
{
	struct strtab typetab[] = {
		{ "QPSK", FE_QPSK,},
		{ "QAM",  FE_QAM, },
		{ "OFDM", FE_OFDM,},
		{ "ATSC", FE_ATSC,},
		{ NULL, 0 }
	};

	return enum2str(t, typetab, "UNK");
}

static int tune_initial (int frontend_fd, const char *initial)
{
	FILE *inif;
	unsigned int f, sr;
	char buf[200];
	char pol[20], fec[20], qam[20], bw[20], fec2[20], mode[20], guard[20], hier[20];
	struct transponder *t;

	inif = fopen(initial, "r");
	if (!inif) {
		error("cannot open '%s': %d %m\n", initial, errno);
		return -1;
	}
	while (fgets(buf, sizeof(buf), inif)) {
		if (buf[0] == '#' || buf[0] == '\n')
			;
		else if (sscanf(buf, "S %u %1[HVLR] %u %4s\n", &f, pol, &sr, fec) == 4) {
			t = alloc_transponder(f);
			t->type = FE_QPSK;
			switch(pol[0]) {
				case 'H':
				case 'L':
					t->polarisation = POLARISATION_HORIZONTAL;
					break;
				default:
					t->polarisation = POLARISATION_VERTICAL;;
					break;
			}
			t->param.inversion = spectral_inversion;
			t->param.u.qpsk.symbol_rate = sr;
			t->param.u.qpsk.fec_inner = str2fec(fec);
			info("initial transponder %u %c %u %d\n",