static int
fifolog_reader_findsync(const struct fifolog_file *ff, off_t *o)
{
int e;
unsigned seq, seqs;
assert(*o < ff->logsize);
e = fifolog_int_read(ff, *o);
if (e)
err(1, "Read error (%d) while looking for SYNC", e);
seq = be32dec(ff->recbuf);
if (*o == 0 && seq == 0)
return (0);
if (ff->recbuf[4] & FIFOLOG_FLG_SYNC)
return (1); /* That was easy... */
while(1) {
assert(*o < ff->logsize);
(*o)++;
seq++;
if (*o == ff->logsize)
return (2); /* wraparound */
e = fifolog_int_read(ff, *o);
if (e)
err(1, "Read error (%d) while looking for SYNC", e);
seqs = be32dec(ff->recbuf);
if (seqs != seq)
return (3); /* End of log */
if (ff->recbuf[4] & FIFOLOG_FLG_SYNC)
return (1); /* Bingo! */
}
}
const char *
fifolog_int_findend(const struct fifolog_file *ff, off_t *last)
{
off_t o, s;
int e;
unsigned seq0, seq;
fifolog_int_file_assert(ff);
o = 0;
e = fifolog_int_read(ff, o);
if (e)
return("Read error, first record");
seq0 = be32dec(ff->recbuf);
/* If the first records sequence is zero, the fifolog is empty */
if (seq0 == 0) {
*last = o;
return (NULL);
}
/* Do a binary search for a discontinuity in the sequence numbers */
s = ff->logsize / 2;
do {
e = fifolog_int_read(ff, o + s);
if (e)
return ("Read error while searching");
seq = be32dec(ff->recbuf);
if (seq == seq0 + s) {
o += s;
seq0 = seq;
}
s /= 2;
assert(o < ff->logsize);
} while (s > 0);
*last = o;
return (NULL);
}
void
fifolog_reader_process(struct fifolog_reader *fr, off_t from, fifolog_reader_render_t *func, void *priv, time_t end)
{
uint32_t seq, lseq;
off_t o = from;
int i, e;
time_t t;
u_char *p, *q;
z_stream *zs;
CHECK_OBJ_NOTNULL(fr, FIFOLOG_READER_MAGIC);
zs = fr->ff->zs;
lseq = 0;
while (1) {
e = fifolog_int_read(fr->ff, o);
if (e)
err(1, "Read error (%d)", e);
if (++o >= fr->ff->logsize)
o = 0;
seq = be32dec(fr->ff->recbuf);
if (lseq != 0 && seq != lseq + 1)
break;
lseq = seq;
zs->avail_in = fr->ff->recsize - 5;
zs->next_in = fr->ff->recbuf + 5;
if (fr->ff->recbuf[4] & FIFOLOG_FLG_1BYTE)
zs->avail_in -= fr->ff->recbuf[fr->ff->recsize - 1];
if (fr->ff->recbuf[4] & FIFOLOG_FLG_4BYTE)
zs->avail_in -=
be32dec(fr->ff->recbuf + fr->ff->recsize - 4);
if (fr->ff->recbuf[4] & FIFOLOG_FLG_SYNC) {
i = inflateReset(zs);
assert(i == Z_OK);
zs->next_out = fr->obuf;
zs->avail_out = fr->olen;
t = be32dec(fr->ff->recbuf + 5);
if (t > end)
break;
zs->next_in += 4;
zs->avail_in -= 4;
}
while(zs->avail_in > 0) {
i = inflate(zs, 0);
if (i == Z_BUF_ERROR) {
#if 1
fprintf(stderr,
"Z_BUF_ERROR [%d,%d] [%d,%d,%d]\n",
(int)(zs->next_in - fr->ff->recbuf),
zs->avail_in,
(int)(zs->next_out - fr->obuf),
zs->avail_out, fr->olen);
exit (250);
#else
i = Z_OK;
#endif
}
if (i == Z_STREAM_END) {
i = inflateReset(zs);
}
if (i != Z_OK) {
fprintf(stderr, "inflate = %d\n", i);
exit (250);
}
assert(i == Z_OK);
if (zs->avail_out != fr->olen) {
q = fr->obuf + (fr->olen - zs->avail_out);
p = fifolog_reader_chop(fr, func, priv);
if (p < q)
(void)memmove(fr->obuf, p, q - p);
zs->avail_out = fr->olen - (q - p);
zs->next_out = fr->obuf + (q - p);
}
}
}
}
off_t
fifolog_reader_seek(const struct fifolog_reader *fr, time_t t0)
{
off_t o, s, st;
time_t t, tt;
unsigned seq, seqs;
const char *retval;
int e;
CHECK_OBJ_NOTNULL(fr, FIFOLOG_READER_MAGIC);
/*
* First, find the first SYNC block
*/
o = 0;
e = fifolog_reader_findsync(fr->ff, &o);
if (e == 0)
return (0); /* empty fifolog */
assert(e == 1);
assert(fr->ff->recbuf[4] & FIFOLOG_FLG_SYNC);
seq = be32dec(fr->ff->recbuf);
t = be32dec(fr->ff->recbuf + 5);
if (t > t0) {
/* Check if there is a second older part we can use */
retval = fifolog_int_findend(fr->ff, &s);
if (retval != NULL)
err(1, "%s", retval);
s++;
e = fifolog_reader_findsync(fr->ff, &s);
if (e == 0)
return (0); /* empty fifolog */
if (e == 1) {
o = s;
seq = be32dec(fr->ff->recbuf);
t = be32dec(fr->ff->recbuf + 5);
}
}
/* Now do a binary search to find the sync block right before t0 */
s = st = (fr->ff->logsize - o) / 2;
while (s > 1) {
/* We know we shouldn't wrap */
if (o + st > fr->ff->logsize + 1) {
s = st = s / 2;
continue;
}
e = fifolog_int_read(fr->ff, o + st);
if (e) {
s = st = s / 2;
continue;
}
/* If not in same part, sequence won't match */
seqs = be32dec(fr->ff->recbuf);
if (seqs != seq + st) {
s = st = s / 2;
continue;
}
/* If not sync block, try next */
if (!(fr->ff->recbuf[4] & FIFOLOG_FLG_SYNC)) {
st++;
continue;
}
/* Check timestamp */
tt = be32dec(fr->ff->recbuf + 5);
if (tt >= t0) {
s = st = s / 2;
continue;
}
o += st;
seq = seqs;
}
fprintf(stderr, "Read from %jx\n", o * fr->ff->recsize);
return (o);
}
const char *
fifolog_write_open(struct fifolog_writer *f, const char *fn,
unsigned writerate, unsigned syncrate, unsigned compression)
{
const char *es;
int i;
time_t now;
off_t o;
CHECK_OBJ_NOTNULL(f, FIFOLOG_WRITER_MAGIC);
/* Check for legal compression value */
if (compression > Z_BEST_COMPRESSION)
return ("Illegal compression value");
f->writerate = writerate;
f->syncrate = syncrate;
f->compression = compression;
/* Reset statistics */
memset(f->cnt, 0, sizeof f->cnt);
es = fifolog_int_open(&f->ff, fn, 1);
if (es != NULL)
return (es);
es = fifolog_int_findend(f->ff, &o);
if (es != NULL)
return (es);
i = fifolog_int_read(f->ff, o);
if (i)
return ("Read error, looking for seq");
f->seq = be32dec(f->ff->recbuf);
if (f->seq == 0) {
/* Empty fifolog */
f->seq = random();
} else {
f->recno = o + 1;
f->seq++;
}
f->obufsize = f->ff->recsize;
ALLOC(&f->obuf, f->obufsize);
f->ibufsize = f->obufsize * 10;
ALLOC(&f->ibuf, f->ibufsize);
f->ibufptr = 0;
i = deflateInit(f->ff->zs, (int)f->compression);
assert(i == Z_OK);
f->flag |= FIFOLOG_FLG_RESTART;
f->flag |= FIFOLOG_FLG_SYNC;
f->ff->zs->next_out = f->obuf + 9;
f->ff->zs->avail_out = f->obufsize - 9;
time(&now);
f->starttime = now;
f->lastsync = now;
f->lastwrite = now;
fifolog_write_assert(f);
return (NULL);
}
