freebsd-dev/usr.sbin/fifolog/lib/fifolog_reader.c
Poul-Henning Kamp fb4f617201 Fix a bunch of trivial whitespace mistakes and update the miniobj.h
file before the real work starts.
2011-02-25 09:40:17 +00:00

323 lines
7.4 KiB
C

/*-
* Copyright (c) 2005-2008 Poul-Henning Kamp
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <stdio.h>
#include <unistd.h>
#include <assert.h>
#include <err.h>
#include <time.h>
#include <string.h>
#include <stdlib.h>
#include <zlib.h>
#include <sys/endian.h>
#include "fifolog.h"
#include "libfifolog.h"
#include "libfifolog_int.h"
#include "miniobj.h"
/*--------------------------------------------------------------------*/
struct fifolog_reader {
unsigned magic;
#define FIFOLOG_READER_MAGIC 0x1036d139
struct fifolog_file *ff;
unsigned olen;
unsigned char *obuf;
time_t now;
};
struct fifolog_reader *
fifolog_reader_open(const char *fname)
{
const char *retval;
struct fifolog_reader *fr;
int i;
fr = calloc(sizeof *fr, 1);
if (fr == NULL)
err(1, "Cannot malloc");
retval = fifolog_int_open(&fr->ff, fname, 0);
if (retval != NULL)
err(1, "%s", retval);
fr->olen = fr->ff->recsize * 16;
fr->obuf = calloc(fr->olen, 1);
if (fr->obuf == NULL)
err(1, "Cannot malloc");
i = inflateInit(fr->ff->zs);
assert(i == Z_OK);
fr->magic = FIFOLOG_READER_MAGIC;
return (fr);
}
/*
* Find the next SYNC block
*
* Return:
* 0 - empty fifolog
* 1 - found sync block
* 2 - would have wrapped around
* 3 - End of written log.
*/
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! */
}
}
/*
* Seek out a given timestamp
*/
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);
}
static unsigned char *
fifolog_reader_chop(struct fifolog_reader *fr, fifolog_reader_render_t *func, void *priv)
{
u_char *p, *q;
uint32_t v, w, u;
p = fr->obuf;
q = fr->obuf + (fr->olen - fr->ff->zs->avail_out);
while (1) {
/* Make sure we have a complete header */
if (p + 5 >= q)
return (p);
w = 4;
u = be32dec(p);
if (u & FIFOLOG_TIMESTAMP) {
fr->now = be32dec(p + 4);
w += 4;
}
if (u & FIFOLOG_LENGTH) {
v = p[w];
w++;
if (p + w + v >= q)
return (p);
} else {
for (v = 0; p + v + w < q && p[v + w] != '\0'; v++)
continue;
if (p + v + w >= q)
return (p);
v++;
}
func(priv, fr->now, u, p + w, v);
p += w + v;
}
}
/*
* Process fifolog until end of written log or provided timestamp
*/
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);
}
}
}
}