lib/libpmc/pmclog.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2005-2007 Joseph Koshy
   5  * Copyright (c) 2007 The FreeBSD Foundation
   6  * All rights reserved.
   7  *
   8  * Portions of this software were developed by A. Joseph Koshy under
   9  * sponsorship from the FreeBSD Foundation and Google, Inc.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 #include <sys/param.h>
  37 #include <sys/pmc.h>
  38 #include <sys/pmclog.h>
  39
  40 #include <assert.h>
  41 #include <errno.h>
  42 #include <pmc.h>
  43 #include <pmclog.h>
  44 #include <stddef.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <strings.h>
  48 #include <unistd.h>
  49 #include <stdio.h>
  50
  51 #include <machine/pmc_mdep.h>
  52
  53 #include "libpmcinternal.h"
  54
  55 #define PMCLOG_BUFFER_SIZE                      4096
  56
  57 /*
  58  * API NOTES
  59  *
  60  * The pmclog(3) API is oriented towards parsing an event stream in
  61  * "realtime", i.e., from an data source that may or may not preserve
  62  * record boundaries -- for example when the data source is elsewhere
  63  * on a network.  The API allows data to be fed into the parser zero
  64  * or more bytes at a time.
  65  *
  66  * The state for a log file parser is maintained in a 'struct
  67  * pmclog_parse_state'.  Parser invocations are done by calling
  68  * 'pmclog_read()'; this function will inform the caller when a
  69  * complete event is parsed.
  70  *
  71  * The parser first assembles a complete log file event in an internal
  72  * work area (see "ps_saved" below).  Once a complete log file event
  73  * is read, the parser then parses it and converts it to an event
  74  * descriptor usable by the client.  We could possibly avoid this two
  75  * step process by directly parsing the input log to set fields in the
  76  * event record.  However the parser's state machine would get
  77  * insanely complicated, and this code is unlikely to be used in
  78  * performance critical paths.
  79  */
  80
  81 enum pmclog_parser_state {
  82         PL_STATE_NEW_RECORD,            /* in-between records */
  83         PL_STATE_EXPECTING_HEADER,      /* header being read */
  84         PL_STATE_PARTIAL_RECORD,        /* header present but not the record */
  85         PL_STATE_ERROR                  /* parsing error encountered */
  86 };
  87
  88 struct pmclog_parse_state {
  89         enum pmclog_parser_state ps_state;
  90         enum pmc_cputype        ps_arch;        /* log file architecture */
  91         uint32_t                ps_version;     /* hwpmc version */
  92         int                     ps_initialized; /* whether initialized */
  93         int                     ps_count;       /* count of records processed */
  94         off_t                   ps_offset;      /* stream byte offset */
  95         union pmclog_entry      ps_saved;       /* saved partial log entry */
  96         int                     ps_svcount;     /* #bytes saved */
  97         int                     ps_fd;          /* active fd or -1 */
  98         char                    *ps_buffer;     /* scratch buffer if fd != -1 */
  99         char                    *ps_data;       /* current parse pointer */
 100         size_t                  ps_len;         /* length of buffered data */
 101 };
 102
 103 #define PMCLOG_HEADER_FROM_SAVED_STATE(PS)                              \
 104         (* ((uint32_t *) &(PS)->ps_saved))
 105
 106 #define PMCLOG_INITIALIZE_READER(LE,A)  LE = (uint32_t *) &(A)
 107 #define PMCLOG_READ32(LE,V)             do {                            \
 108                 (V)  = *(LE)++;                                         \
 109         } while (0)
 110 #define PMCLOG_READ64(LE,V)             do {                            \
 111                 uint64_t _v;                                            \
 112                 _v  = (uint64_t) *(LE)++;                               \
 113                 _v |= ((uint64_t) *(LE)++) << 32;                       \
 114                 (V) = _v;                                               \
 115         } while (0)
 116
 117 #define PMCLOG_READSTRING(LE,DST,LEN)   strlcpy((DST), (char *) (LE), (LEN))
 118
 119 /*
 120  * Assemble a log record from '*len' octets starting from address '*data'.
 121  * Update 'data' and 'len' to reflect the number of bytes consumed.
 122  *
 123  * '*data' is potentially an unaligned address and '*len' octets may
 124  * not be enough to complete a event record.
 125  */
 126
 127 static enum pmclog_parser_state
 128 pmclog_get_record(struct pmclog_parse_state *ps, char **data, ssize_t *len)
 129 {
 130         int avail, copylen, recordsize, used;
 131         uint32_t h;
 132         const int HEADERSIZE = sizeof(uint32_t);
 133         char *src, *dst;
 134
 135         if ((avail = *len) <= 0)
 136                 return (ps->ps_state = PL_STATE_ERROR);
 137
 138         src = *data;
 139         used = 0;
 140
 141         if (ps->ps_state == PL_STATE_NEW_RECORD)
 142                 ps->ps_svcount = 0;
 143
 144         dst = (char *) &ps->ps_saved + ps->ps_svcount;
 145
 146         switch (ps->ps_state) {
 147         case PL_STATE_NEW_RECORD:
 148
 149                 /*
 150                  * Transitions:
 151                  *
 152                  * Case A: avail < headersize
 153                  *      -> 'expecting header'
 154                  *
 155                  * Case B: avail >= headersize
 156                  *    B.1: avail < recordsize
 157                  *         -> 'partial record'
 158                  *    B.2: avail >= recordsize
 159                  *         -> 'new record'
 160                  */
 161
 162                 copylen = avail < HEADERSIZE ? avail : HEADERSIZE;
 163                 bcopy(src, dst, copylen);
 164                 ps->ps_svcount = used = copylen;
 165
 166                 if (copylen < HEADERSIZE) {
 167                         ps->ps_state = PL_STATE_EXPECTING_HEADER;
 168                         goto done;
 169                 }
 170
 171                 src += copylen;
 172                 dst += copylen;
 173
 174                 h = PMCLOG_HEADER_FROM_SAVED_STATE(ps);
 175                 recordsize = PMCLOG_HEADER_TO_LENGTH(h);
 176
 177                 if (recordsize <= 0)
 178                         goto error;
 179
 180                 if (recordsize <= avail) { /* full record available */
 181                         bcopy(src, dst, recordsize - copylen);
 182                         ps->ps_svcount = used = recordsize;
 183                         goto done;
 184                 }
 185
 186                 /* header + a partial record is available */
 187                 bcopy(src, dst, avail - copylen);
 188                 ps->ps_svcount = used = avail;
 189                 ps->ps_state = PL_STATE_PARTIAL_RECORD;
 190
 191                 break;
 192
 193         case PL_STATE_EXPECTING_HEADER:
 194
 195                 /*
 196                  * Transitions:
 197                  *
 198                  * Case C: avail+saved < headersize
 199                  *      -> 'expecting header'
 200                  *
 201                  * Case D: avail+saved >= headersize
 202                  *    D.1: avail+saved < recordsize
 203                  *      -> 'partial record'
 204                  *    D.2: avail+saved >= recordsize
 205                  *      -> 'new record'
 206                  *    (see PARTIAL_RECORD handling below)
 207                  */
 208
 209                 if (avail + ps->ps_svcount < HEADERSIZE) {
 210                         bcopy(src, dst, avail);
 211                         ps->ps_svcount += avail;
 212                         used = avail;
 213                         break;
 214                 }
 215
 216                 used = copylen = HEADERSIZE - ps->ps_svcount;
 217                 bcopy(src, dst, copylen);
 218                 src += copylen;
 219                 dst += copylen;
 220                 avail -= copylen;
 221                 ps->ps_svcount += copylen;
 222
 223                 /*FALLTHROUGH*/
 224
 225         case PL_STATE_PARTIAL_RECORD:
 226
 227                 /*
 228                  * Transitions:
 229                  *
 230                  * Case E: avail+saved < recordsize
 231                  *      -> 'partial record'
 232                  *
 233                  * Case F: avail+saved >= recordsize
 234                  *      -> 'new record'
 235                  */
 236
 237                 h = PMCLOG_HEADER_FROM_SAVED_STATE(ps);
 238                 recordsize = PMCLOG_HEADER_TO_LENGTH(h);
 239
 240                 if (recordsize <= 0)
 241                         goto error;
 242
 243                 if (avail + ps->ps_svcount < recordsize) {
 244                         copylen = avail;
 245                         ps->ps_state = PL_STATE_PARTIAL_RECORD;
 246                 } else {
 247                         copylen = recordsize - ps->ps_svcount;
 248                         ps->ps_state = PL_STATE_NEW_RECORD;
 249                 }
 250
 251                 bcopy(src, dst, copylen);
 252                 ps->ps_svcount += copylen;
 253                 used += copylen;
 254                 break;
 255
 256         default:
 257                 goto error;
 258         }
 259
 260  done:
 261         *data += used;
 262         *len  -= used;
 263         return ps->ps_state;
 264
 265  error:
 266         ps->ps_state = PL_STATE_ERROR;
 267         return ps->ps_state;
 268 }
 269
 270 /*
 271  * Get an event from the stream pointed to by '*data'.  '*len'
 272  * indicates the number of bytes available to parse.  Arguments
 273  * '*data' and '*len' are updated to indicate the number of bytes
 274  * consumed.
 275  */
 276
 277 static int
 278 pmclog_get_event(void *cookie, char **data, ssize_t *len,
 279     struct pmclog_ev *ev)
 280 {
 281         int evlen, pathlen;
 282         uint32_t h, *le, npc, noop;
 283         enum pmclog_parser_state e;
 284         struct pmclog_parse_state *ps;
 285
 286         ps = (struct pmclog_parse_state *) cookie;
 287
 288         assert(ps->ps_state != PL_STATE_ERROR);
 289
 290         if ((e = pmclog_get_record(ps,data,len)) == PL_STATE_ERROR) {
 291                 ev->pl_state = PMCLOG_ERROR;
 292                 printf("state error\n");
 293                 return -1;
 294         }
 295
 296         if (e != PL_STATE_NEW_RECORD) {
 297                 ev->pl_state = PMCLOG_REQUIRE_DATA;
 298                 return -1;
 299         }
 300
 301         PMCLOG_INITIALIZE_READER(le, ps->ps_saved);
 302
 303         PMCLOG_READ32(le,h);
 304
 305         if (!PMCLOG_HEADER_CHECK_MAGIC(h)) {
 306                 printf("bad magic\n");
 307                 ps->ps_state = PL_STATE_ERROR;
 308                 ev->pl_state = PMCLOG_ERROR;
 309                 return -1;
 310         }
 311
 312         /* copy out the time stamp */
 313         PMCLOG_READ32(le,ev->pl_ts.tv_sec);
 314         PMCLOG_READ32(le,ev->pl_ts.tv_nsec);
 315
 316         evlen = PMCLOG_HEADER_TO_LENGTH(h);
 317
 318 #define PMCLOG_GET_PATHLEN(P,E,TYPE) do {                               \
 319                 (P) = (E) - offsetof(struct TYPE, pl_pathname);         \
 320                 if ((P) > PATH_MAX || (P) < 0)                          \
 321                         goto error;                                     \
 322         } while (0)
 323
 324 #define PMCLOG_GET_CALLCHAIN_SIZE(SZ,E) do {                            \
 325                 (SZ) = ((E) - offsetof(struct pmclog_callchain, pl_pc)) \
 326                         / sizeof(uintfptr_t);                           \
 327         } while (0);
 328
 329         switch (ev->pl_type = PMCLOG_HEADER_TO_TYPE(h)) {
 330         case PMCLOG_TYPE_CALLCHAIN:
 331                 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_pid);
 332                 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_tid);
 333                 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_pmcid);
 334                 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_cpuflags);
 335                 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_cpuflags2);
 336                 PMCLOG_GET_CALLCHAIN_SIZE(ev->pl_u.pl_cc.pl_npc,evlen);
 337                 for (npc = 0; npc < ev->pl_u.pl_cc.pl_npc; npc++)
 338                         PMCLOG_READADDR(le,ev->pl_u.pl_cc.pl_pc[npc]);
 339                 for (;npc < PMC_CALLCHAIN_DEPTH_MAX; npc++)
 340                         ev->pl_u.pl_cc.pl_pc[npc] = (uintfptr_t) 0;
 341                 break;
 342         case PMCLOG_TYPE_CLOSELOG:
 343                 ev->pl_state = PMCLOG_EOF;
 344                 return (-1);
 345         case PMCLOG_TYPE_DROPNOTIFY:
 346                 /* nothing to do */
 347                 break;
 348         case PMCLOG_TYPE_INITIALIZE:
 349                 PMCLOG_READ32(le,ev->pl_u.pl_i.pl_version);
 350                 PMCLOG_READ32(le,ev->pl_u.pl_i.pl_arch);
 351                 ps->ps_version = ev->pl_u.pl_i.pl_version;
 352                 ps->ps_arch = ev->pl_u.pl_i.pl_arch;
 353                 ps->ps_initialized = 1;
 354                 break;
 355         case PMCLOG_TYPE_MAP_IN:
 356                 PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_map_in);
 357                 PMCLOG_READ32(le,ev->pl_u.pl_mi.pl_pid);
 358                 PMCLOG_READADDR(le,ev->pl_u.pl_mi.pl_start);
 359                 PMCLOG_READSTRING(le, ev->pl_u.pl_mi.pl_pathname, pathlen);
 360                 break;
 361         case PMCLOG_TYPE_MAP_OUT:
 362                 PMCLOG_READ32(le,ev->pl_u.pl_mo.pl_pid);
 363                 PMCLOG_READADDR(le,ev->pl_u.pl_mo.pl_start);
 364                 PMCLOG_READADDR(le,ev->pl_u.pl_mo.pl_end);
 365                 break;
 366         case PMCLOG_TYPE_PMCALLOCATE:
 367                 PMCLOG_READ32(le,ev->pl_u.pl_a.pl_pmcid);
 368                 PMCLOG_READ32(le,ev->pl_u.pl_a.pl_event);
 369                 PMCLOG_READ32(le,ev->pl_u.pl_a.pl_flags);
 370                 PMCLOG_READ32(le,noop);
 371                 ev->pl_u.pl_a.pl_evname = pmc_pmu_event_get_by_idx(ev->pl_u.pl_a.pl_event);
 372                 if (ev->pl_u.pl_a.pl_evname != NULL)
 373                         break;
 374                 else if ((ev->pl_u.pl_a.pl_evname =
 375                     _pmc_name_of_event(ev->pl_u.pl_a.pl_event, ps->ps_arch))
 376                     == NULL) {
 377                         printf("unknown event\n");
 378                         goto error;
 379                 }
 380                 break;
 381         case PMCLOG_TYPE_PMCALLOCATEDYN:
 382                 PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_pmcid);
 383                 PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_event);
 384                 PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_flags);
 385                 PMCLOG_READSTRING(le,ev->pl_u.pl_ad.pl_evname,PMC_NAME_MAX);
 386                 break;
 387         case PMCLOG_TYPE_PMCATTACH:
 388                 PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_pmcattach);
 389                 PMCLOG_READ32(le,ev->pl_u.pl_t.pl_pmcid);
 390                 PMCLOG_READ32(le,ev->pl_u.pl_t.pl_pid);
 391                 PMCLOG_READSTRING(le,ev->pl_u.pl_t.pl_pathname,pathlen);
 392                 break;
 393         case PMCLOG_TYPE_PMCDETACH:
 394                 PMCLOG_READ32(le,ev->pl_u.pl_d.pl_pmcid);
 395                 PMCLOG_READ32(le,ev->pl_u.pl_d.pl_pid);
 396                 break;
 397         case PMCLOG_TYPE_PROCCSW:
 398                 PMCLOG_READ32(le,ev->pl_u.pl_c.pl_pmcid);
 399                 PMCLOG_READ64(le,ev->pl_u.pl_c.pl_value);
 400                 PMCLOG_READ32(le,ev->pl_u.pl_c.pl_pid);
 401                 PMCLOG_READ32(le,ev->pl_u.pl_c.pl_tid);
 402                 break;
 403         case PMCLOG_TYPE_PROCEXEC:
 404                 PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_procexec);
 405                 PMCLOG_READ32(le,ev->pl_u.pl_x.pl_pid);
 406                 PMCLOG_READ32(le,ev->pl_u.pl_x.pl_pmcid);
 407                 PMCLOG_READ32(le,noop);
 408                 PMCLOG_READADDR(le,ev->pl_u.pl_x.pl_entryaddr);
 409                 PMCLOG_READSTRING(le,ev->pl_u.pl_x.pl_pathname,pathlen);
 410                 break;
 411         case PMCLOG_TYPE_PROCEXIT:
 412                 PMCLOG_READ32(le,ev->pl_u.pl_e.pl_pmcid);
 413                 PMCLOG_READ32(le,ev->pl_u.pl_e.pl_pid);
 414                 PMCLOG_READ32(le,noop);
 415                 PMCLOG_READ64(le,ev->pl_u.pl_e.pl_value);
 416                 break;
 417         case PMCLOG_TYPE_PROCFORK:
 418                 PMCLOG_READ32(le,ev->pl_u.pl_f.pl_oldpid);
 419                 PMCLOG_READ32(le,ev->pl_u.pl_f.pl_newpid);
 420                 break;
 421         case PMCLOG_TYPE_SYSEXIT:
 422                 PMCLOG_READ32(le,ev->pl_u.pl_se.pl_pid);
 423                 break;
 424         case PMCLOG_TYPE_USERDATA:
 425                 PMCLOG_READ32(le,ev->pl_u.pl_u.pl_userdata);
 426                 break;
 427         default:        /* unknown record type */
 428                 ps->ps_state = PL_STATE_ERROR;
 429                 ev->pl_state = PMCLOG_ERROR;
 430                 return (-1);
 431         }
 432
 433         ev->pl_offset = (ps->ps_offset += evlen);
 434         ev->pl_count  = (ps->ps_count += 1);
 435         ev->pl_state = PMCLOG_OK;
 436         return 0;
 437
 438  error:
 439         ev->pl_state = PMCLOG_ERROR;
 440         ps->ps_state = PL_STATE_ERROR;
 441         return -1;
 442 }
 443
 444 /*
 445  * Extract and return the next event from the byte stream.
 446  *
 447  * Returns 0 and sets the event's state to PMCLOG_OK in case an event
 448  * was successfully parsed.  Otherwise this function returns -1 and
 449  * sets the event's state to one of PMCLOG_REQUIRE_DATA (if more data
 450  * is needed) or PMCLOG_EOF (if an EOF was seen) or PMCLOG_ERROR if
 451  * a parse error was encountered.
 452  */
 453
 454 int
 455 pmclog_read(void *cookie, struct pmclog_ev *ev)
 456 {
 457         int retval;
 458         ssize_t nread;
 459         struct pmclog_parse_state *ps;
 460
 461         ps = (struct pmclog_parse_state *) cookie;
 462
 463         if (ps->ps_state == PL_STATE_ERROR) {
 464                 ev->pl_state = PMCLOG_ERROR;
 465                 return -1;
 466         }
 467
 468         /*
 469          * If there isn't enough data left for a new event try and get
 470          * more data.
 471          */
 472         if (ps->ps_len == 0) {
 473                 ev->pl_state = PMCLOG_REQUIRE_DATA;
 474
 475                 /*
 476                  * If we have a valid file descriptor to read from, attempt
 477                  * to read from that.  This read may return with an error,
 478                  * (which may be EAGAIN or other recoverable error), or
 479                  * can return EOF.
 480                  */
 481                 if (ps->ps_fd != PMCLOG_FD_NONE) {
 482                 refill:
 483                         nread = read(ps->ps_fd, ps->ps_buffer,
 484                             PMCLOG_BUFFER_SIZE);
 485
 486                         if (nread <= 0) {
 487                                 if (nread == 0)
 488                                         ev->pl_state = PMCLOG_EOF;
 489                                 else if (errno != EAGAIN) /* not restartable */
 490                                         ev->pl_state = PMCLOG_ERROR;
 491                                 return -1;
 492                         }
 493
 494                         ps->ps_len = nread;
 495                         ps->ps_data = ps->ps_buffer;
 496                 } else {
 497                         return -1;
 498                 }
 499         }
 500
 501         assert(ps->ps_len > 0);
 502
 503
 504          /* Retrieve one event from the byte stream. */
 505         retval = pmclog_get_event(ps, &ps->ps_data, &ps->ps_len, ev);
 506         /*
 507          * If we need more data and we have a configured fd, try read
 508          * from it.
 509          */
 510         if (retval < 0 && ev->pl_state == PMCLOG_REQUIRE_DATA &&
 511             ps->ps_fd != -1) {
 512                 assert(ps->ps_len == 0);
 513                 goto refill;
 514         }
 515
 516         return retval;
 517 }
 518
 519 /*
 520  * Feed data to a memory based parser.
 521  *
 522  * The memory area pointed to by 'data' needs to be valid till the
 523  * next error return from pmclog_next_event().
 524  */
 525
 526 int
 527 pmclog_feed(void *cookie, char *data, int len)
 528 {
 529         struct pmclog_parse_state *ps;
 530
 531         ps = (struct pmclog_parse_state *) cookie;
 532
 533         if (len < 0 ||          /* invalid length */
 534             ps->ps_buffer ||    /* called for a file parser */
 535             ps->ps_len != 0)    /* unnecessary call */
 536                 return -1;
 537
 538         ps->ps_data = data;
 539         ps->ps_len  = len;
 540
 541         return 0;
 542 }
 543
 544 /*
 545  * Allocate and initialize parser state.
 546  */
 547
 548 void *
 549 pmclog_open(int fd)
 550 {
 551         struct pmclog_parse_state *ps;
 552
 553         if ((ps = (struct pmclog_parse_state *) malloc(sizeof(*ps))) == NULL)
 554                 return NULL;
 555
 556         ps->ps_state = PL_STATE_NEW_RECORD;
 557         ps->ps_arch = -1;
 558         ps->ps_initialized = 0;
 559         ps->ps_count = 0;
 560         ps->ps_offset = (off_t) 0;
 561         bzero(&ps->ps_saved, sizeof(ps->ps_saved));
 562         ps->ps_svcount = 0;
 563         ps->ps_fd    = fd;
 564         ps->ps_data  = NULL;
 565         ps->ps_buffer = NULL;
 566         ps->ps_len   = 0;
 567
 568         /* allocate space for a work area */
 569         if (ps->ps_fd != PMCLOG_FD_NONE) {
 570                 if ((ps->ps_buffer = malloc(PMCLOG_BUFFER_SIZE)) == NULL) {
 571                         free(ps);
 572                         return NULL;
 573                 }
 574         }
 575
 576         return ps;
 577 }
 578
 579
 580 /*
 581  * Free up parser state.
 582  */
 583
 584 void
 585 pmclog_close(void *cookie)
 586 {
 587         struct pmclog_parse_state *ps;
 588
 589         ps = (struct pmclog_parse_state *) cookie;
 590
 591         if (ps->ps_buffer)
 592                 free(ps->ps_buffer);
 593
 594         free(ps);
 595 }