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descrambler: use inlines for key conditions, fix the key_late() condition

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This commit is contained in:
Jaroslav Kysela 2014-08-09 15:15:09 +02:00
parent 46b261f687
commit 88e692cd9e
1 changed files with 27 additions and 12 deletions
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39
src/descrambler/descrambler.c
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@ -280,17 +280,37 @@ key_update( th_descrambler_runtime_t *dr, uint8_t key )
dr->dr_key_start = dispatch_clock - 60;
}
static inline int
key_valid ( th_descrambler_runtime_t *dr, uint8_t ki )
{
/* 0x40 (for even) or 0x80 (for odd) */
uint8_t mask = ((ki & 0x40) + 0x40);
return dr->dr_key_valid & mask;
}
static inline int
key_late( th_descrambler_runtime_t *dr, uint8_t ki )
{
uint8_t kidx = (ki & 0x40) >> 6;
/* required key is older than previous? */
if (dr->dr_key_timestamp[kidx] < dr->dr_key_timestamp[kidx^1]) {
/* but don't take in account the keys modified just now */
if (dr->dr_key_timestamp[kidx^1] + 2 < dispatch_clock)
return 1;
}
/* ECM was sent, but no new key was received */
return dr->dr_ecm_key_time + 2 < dr->dr_key_start;
}
int
descrambler_descramble ( service_t *t,
elementary_stream_t *st,
const uint8_t *tsb )
{
#define KEY_MASK(k) (((k) & 0x40) + 0x40) /* 0x40 (for even) or 0x80 (for odd) */
#define KEY_IDX(k) (((k) & 0x40) >> 6)
th_descrambler_t *td;
th_descrambler_runtime_t *dr = t->s_descramble;
int count, failed, off, size, flush_data = 0;
uint8_t *tsb2, ki, kidx;
uint8_t *tsb2, ki;
lock_assert(&t->s_stream_mutex);
@ -310,7 +330,7 @@ descrambler_descramble ( service_t *t,
tsb2 = dr->dr_buf.sb_data + off;
ki = tsb2[3];
if ((ki & 0x80) != 0x00) {
if ((dr->dr_key_valid & KEY_MASK(ki)) == 0) {
if (key_valid(dr, ki) == 0) {
sbuf_cut(&dr->dr_buf, off);
goto next2;
}
@ -319,9 +339,7 @@ descrambler_descramble ( service_t *t,
tvhtrace("descrambler", "stream key changed to %s for service \"%s\"",
(ki & 0x40) ? "odd" : "even",
((mpegts_service_t *)t)->s_dvb_svcname);
kidx = KEY_IDX(ki);
if (dr->dr_key_timestamp[kidx] < dr->dr_key_timestamp[kidx^1] ||
dr->dr_ecm_key_time + 2 < dr->dr_key_start) {
if (key_late(dr, ki)) {
sbuf_cut(&dr->dr_buf, off);
if (!td->td_ecm_reset(td)) {
dr->dr_key_valid = 0;
@ -340,7 +358,7 @@ descrambler_descramble ( service_t *t,
}
ki = tsb[3];
if ((ki & 0x80) != 0x00) {
if ((dr->dr_key_valid & KEY_MASK(ki)) == 0) {
if (key_valid(dr, ki) == 0) {
limitedlog(&dr->dr_loglimit_key, "descrambler",
((mpegts_service_t *)t)->s_dvb_svcname,
(ki & 0x40) ? "odd stream key is not valid" :
@ -352,9 +370,7 @@ descrambler_descramble ( service_t *t,
tvhtrace("descrambler", "stream key changed to %s for service \"%s\"",
(ki & 0x40) ? "odd" : "even",
((mpegts_service_t *)t)->s_dvb_svcname);
kidx = KEY_IDX(ki);
if (dr->dr_key_timestamp[kidx] < dr->dr_key_timestamp[kidx^1] ||
dr->dr_ecm_key_time + 2 < dr->dr_key_start) {
if (key_late(dr, ki)) {
tvhtrace("descrambler", "ECM late (%ld seconds) for service \"%s\"",
dispatch_clock - dr->dr_ecm_key_time,
((mpegts_service_t *)t)->s_dvb_svcname);
@ -428,7 +444,6 @@ next2:
if (count && count == failed)
return -1;
return count;
#undef KEY_MASK
}
static int