pack.c

/***************************************************************************
 * pack.c:
 *
 * Generic routines to pack Mini-SEED records using an MSrecord as a
 * header template and data source.
 *
 * Written by Chad Trabant,
 *   IRIS Data Management Center
 *
 * modified: 2015.273
 ***************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#include "libmseed.h"
#include "packdata.h"

/* Function(s) internal to this file */
static int msr_pack_header_raw (MSRecord *msr, char *rawrec, int maxheaderlen,
                                flag swapflag, flag normalize,
                                struct blkt_1001_s **blkt1001,
                                char *srcname, flag verbose);
static int msr_update_header (MSRecord *msr, char *rawrec, flag swapflag,
                              struct blkt_1001_s *blkt1001,
                              char *srcname, flag verbose);
static int msr_pack_data (void *dest, void *src, int maxsamples, int maxdatabytes,
                          int32_t *lastintsample, flag comphistory,
                          char sampletype, flag encoding, flag swapflag,
                          char *srcname, flag verbose);

/* Header and data byte order flags controlled by environment variables */
/* -2 = not checked, -1 = checked but not set, or 0 = LE and 1 = BE */
flag packheaderbyteorder = -2;
flag packdatabyteorder   = -2;

/***************************************************************************
 * msr_pack:
 *
 * Pack data into SEED data records.  Using the record header values
 * in the MSRecord as a template the common header fields are packed
 * into the record header, blockettes in the blockettes chain are
 * packed and data samples are packed in the encoding format indicated
 * by the MSRecord->encoding field.  A Blockette 1000 will be added if
 * one is not present.
 *
 * The MSRecord->datasamples array and MSRecord->numsamples value will
 * not be changed by this routine.  It is the responsibility of the
 * calling routine to adjust the data buffer if desired.
 *
 * As each record is filled and finished they are passed to
 * record_handler which expects 1) a char * to the record, 2) the
 * length of the record and 3) a pointer supplied by the original
 * caller containing optional private data (handlerdata).  It is the
 * responsibility of record_handler to process the record, the memory
 * will be re-used or freed when record_handler returns.
 *
 * If the flush flag != 0 all of the data will be packed into data
 * records even though the last one will probably not be filled.
 *
 * Default values are: data record & quality indicator = 'D', record
 * length = 4096, encoding = 11 (Steim2) and byteorder = 1 (MSBF).
 * The defaults are triggered when the the msr->dataquality is 0 or
 * msr->reclen, msr->encoding and msr->byteorder are -1 respectively.
 *
 * Returns the number of records created on success and -1 on error.
 ***************************************************************************/
int
msr_pack (MSRecord *msr, void (*record_handler) (char *, int, void *),
          void *handlerdata, int64_t *packedsamples, flag flush, flag verbose)
{
  uint16_t *HPnumsamples;
  uint16_t *HPdataoffset;
  struct blkt_1001_s *HPblkt1001 = NULL;

  char *rawrec;
  char *envvariable;
  char srcname[50];

  flag headerswapflag = 0;
  flag dataswapflag   = 0;

  int samplesize;
  int headerlen;
  int dataoffset;
  int maxdatabytes;
  int maxsamples;
  int recordcnt = 0;
  int packsamples, packoffset;
  int64_t totalpackedsamples;
  hptime_t segstarttime;

  if (!msr)
    return -1;

  if (!record_handler)
  {
    ms_log (2, "msr_pack(): record_handler() function pointer not set!\n");
    return -1;
  }

  /* Allocate stream processing state space if needed */
  if (!msr->ststate)
  {
    msr->ststate = (StreamState *)malloc (sizeof (StreamState));
    if (!msr->ststate)
    {
      ms_log (2, "msr_pack(): Could not allocate memory for StreamState\n");
      return -1;
    }
    memset (msr->ststate, 0, sizeof (StreamState));
  }

  /* Generate source name for MSRecord */
  if (msr_srcname (msr, srcname, 1) == NULL)
  {
    ms_log (2, "msr_unpack_data(): Cannot generate srcname\n");
    return MS_GENERROR;
  }

  /* Track original segment start time for new start time calculation */
  segstarttime = msr->starttime;

  /* Read possible environmental variables that force byteorder */
  if (packheaderbyteorder == -2)
  {
    if ((envvariable = getenv ("PACK_HEADER_BYTEORDER")))
    {
      if (*envvariable != '0' && *envvariable != '1')
      {
        ms_log (2, "Environment variable PACK_HEADER_BYTEORDER must be set to '0' or '1'\n");
        return -1;
      }
      else if (*envvariable == '0')
      {
        packheaderbyteorder = 0;
        if (verbose > 2)
          ms_log (1, "PACK_HEADER_BYTEORDER=0, packing little-endian header\n");
      }
      else
      {
        packheaderbyteorder = 1;
        if (verbose > 2)
          ms_log (1, "PACK_HEADER_BYTEORDER=1, packing big-endian header\n");
      }
    }
    else
    {
      packheaderbyteorder = -1;
    }
  }
  if (packdatabyteorder == -2)
  {
    if ((envvariable = getenv ("PACK_DATA_BYTEORDER")))
    {
      if (*envvariable != '0' && *envvariable != '1')
      {
        ms_log (2, "Environment variable PACK_DATA_BYTEORDER must be set to '0' or '1'\n");
        return -1;
      }
      else if (*envvariable == '0')
      {
        packdatabyteorder = 0;
        if (verbose > 2)
          ms_log (1, "PACK_DATA_BYTEORDER=0, packing little-endian data samples\n");
      }
      else
      {
        packdatabyteorder = 1;
        if (verbose > 2)
          ms_log (1, "PACK_DATA_BYTEORDER=1, packing big-endian data samples\n");
      }
    }
    else
    {
      packdatabyteorder = -1;
    }
  }

  /* Set default indicator, record length, byte order and encoding if needed */
  if (msr->dataquality == 0)
    msr->dataquality = 'D';
  if (msr->reclen == -1)
    msr->reclen = 4096;
  if (msr->byteorder == -1)
    msr->byteorder = 1;
  if (msr->encoding == -1)
    msr->encoding = DE_STEIM2;

  /* Cleanup/reset sequence number */
  if (msr->sequence_number <= 0 || msr->sequence_number > 999999)
    msr->sequence_number = 1;

  if (msr->reclen < MINRECLEN || msr->reclen > MAXRECLEN)
  {
    ms_log (2, "msr_pack(%s): Record length is out of range: %d\n",
            srcname, msr->reclen);
    return -1;
  }

  if (msr->numsamples <= 0)
  {
    ms_log (2, "msr_pack(%s): No samples to pack\n", srcname);
    return -1;
  }

  samplesize = ms_samplesize (msr->sampletype);

  if (!samplesize)
  {
    ms_log (2, "msr_pack(%s): Unknown sample type '%c'\n",
            srcname, msr->sampletype);
    return -1;
  }

  /* Sanity check for msr/quality indicator */
  if (!MS_ISDATAINDICATOR (msr->dataquality))
  {
    ms_log (2, "msr_pack(%s): Record header & quality indicator unrecognized: '%c'\n",
            srcname, msr->dataquality);
    ms_log (2, "msr_pack(%s): Packing failed.\n", srcname);
    return -1;
  }

  /* Allocate space for data record */
  rawrec = (char *)malloc (msr->reclen);

  if (rawrec == NULL)
  {
    ms_log (2, "msr_pack(%s): Cannot allocate memory\n", srcname);
    return -1;
  }

  /* Set header pointers to known offsets into FSDH */
  HPnumsamples = (uint16_t *)(rawrec + 30);
  HPdataoffset = (uint16_t *)(rawrec + 44);

  /* Check to see if byte swapping is needed */
  if (msr->byteorder != ms_bigendianhost ())
    headerswapflag = dataswapflag = 1;

  /* Check if byte order is forced */
  if (packheaderbyteorder >= 0)
  {
    headerswapflag = (msr->byteorder != packheaderbyteorder) ? 1 : 0;
  }

  if (packdatabyteorder >= 0)
  {
    dataswapflag = (msr->byteorder != packdatabyteorder) ? 1 : 0;
  }

  if (verbose > 2)
  {
    if (headerswapflag && dataswapflag)
      ms_log (1, "%s: Byte swapping needed for packing of header and data samples\n", srcname);
    else if (headerswapflag)
      ms_log (1, "%s: Byte swapping needed for packing of header\n", srcname);
    else if (dataswapflag)
      ms_log (1, "%s: Byte swapping needed for packing of data samples\n", srcname);
    else
      ms_log (1, "%s: Byte swapping NOT needed for packing\n", srcname);
  }

  /* Add a blank 1000 Blockette if one is not present, the blockette values
     will be populated in msr_pack_header_raw()/msr_normalize_header() */
  if (!msr->Blkt1000)
  {
    struct blkt_1000_s blkt1000;
    memset (&blkt1000, 0, sizeof (struct blkt_1000_s));

    if (verbose > 2)
      ms_log (1, "%s: Adding 1000 Blockette\n", srcname);

    if (!msr_addblockette (msr, (char *)&blkt1000, sizeof (struct blkt_1000_s), 1000, 0))
    {
      ms_log (2, "msr_pack(%s): Error adding 1000 Blockette\n", srcname);
      free (rawrec);
      return -1;
    }
  }

  headerlen = msr_pack_header_raw (msr, rawrec, msr->reclen, headerswapflag, 1,
                                   &HPblkt1001, srcname, verbose);

  if (headerlen == -1)
  {
    ms_log (2, "msr_pack(%s): Error packing header\n", srcname);
    free (rawrec);
    return -1;
  }

  /* Determine offset to encoded data */
  if (msr->encoding == DE_STEIM1 || msr->encoding == DE_STEIM2)
  {
    dataoffset = 64;
    while (dataoffset < headerlen)
      dataoffset += 64;

    /* Zero memory between blockettes and data if any */
    memset (rawrec + headerlen, 0, dataoffset - headerlen);
  }
  else
  {
    dataoffset = headerlen;
  }

  *HPdataoffset = (uint16_t)dataoffset;
  if (headerswapflag)
    ms_gswap2 (HPdataoffset);

  /* Determine the max data bytes and sample count */
  maxdatabytes = msr->reclen - dataoffset;

  if (msr->encoding == DE_STEIM1)
  {
    maxsamples = (int)(maxdatabytes / 64) * STEIM1_FRAME_MAX_SAMPLES;
  }
  else if (msr->encoding == DE_STEIM2)
  {
    maxsamples = (int)(maxdatabytes / 64) * STEIM2_FRAME_MAX_SAMPLES;
  }
  else
  {
    maxsamples = maxdatabytes / samplesize;
  }

  /* Pack samples into records */
  *HPnumsamples      = 0;
  totalpackedsamples = 0;
  packoffset         = 0;
  if (packedsamples)
    *packedsamples = 0;

  while ((msr->numsamples - totalpackedsamples) > maxsamples || flush)
  {
    packsamples = msr_pack_data (rawrec + dataoffset,
                                 (char *)msr->datasamples + packoffset,
                                 (int)(msr->numsamples - totalpackedsamples), maxdatabytes,
                                 &msr->ststate->lastintsample, msr->ststate->comphistory,
                                 msr->sampletype, msr->encoding, dataswapflag,
                                 srcname, verbose);

    if (packsamples < 0)
    {
      ms_log (2, "msr_pack(%s): Error packing data samples\n", srcname);
      free (rawrec);
      return -1;
    }

    packoffset += packsamples * samplesize;

    /* Update number of samples */
    *HPnumsamples = (uint16_t)packsamples;
    if (headerswapflag)
      ms_gswap2 (HPnumsamples);

    if (verbose > 0)
      ms_log (1, "%s: Packed %d samples\n", srcname, packsamples);

    /* Send record to handler */
    record_handler (rawrec, msr->reclen, handlerdata);

    totalpackedsamples += packsamples;
    if (packedsamples)
      *packedsamples = totalpackedsamples;
    msr->ststate->packedsamples += packsamples;

    /* Update record header for next record */
    msr->sequence_number = (msr->sequence_number >= 999999) ? 1 : msr->sequence_number + 1;
    if (msr->samprate > 0)
      msr->starttime = segstarttime + (hptime_t) (totalpackedsamples / msr->samprate * HPTMODULUS + 0.5);

    msr_update_header (msr, rawrec, headerswapflag, HPblkt1001, srcname, verbose);

    recordcnt++;
    msr->ststate->packedrecords++;

    /* Set compression history flag for subsequent records (Steim encodings) */
    if (!msr->ststate->comphistory)
      msr->ststate->comphistory = 1;

    if (totalpackedsamples >= msr->numsamples)
      break;
  }

  if (verbose > 2)
    ms_log (1, "%s: Packed %d total samples\n", srcname, totalpackedsamples);

  free (rawrec);

  return recordcnt;
} /* End of msr_pack() */

/***************************************************************************
 * msr_pack_header:
 *
 * Pack data header/blockettes into the SEED record at
 * MSRecord->record.  Unlike msr_pack no default values are applied,
 * the header structures are expected to be self describing and no
 * Blockette 1000 will be added.  This routine is only useful for
 * re-packing a record header.
 *
 * Returns the header length in bytes on success and -1 on error.
 ***************************************************************************/
int
msr_pack_header (MSRecord *msr, flag normalize, flag verbose)
{
  char srcname[50];
  char *envvariable;
  flag headerswapflag = 0;
  int headerlen;
  int maxheaderlen;

  if (!msr)
    return -1;

  /* Generate source name for MSRecord */
  if (msr_srcname (msr, srcname, 1) == NULL)
  {
    ms_log (2, "msr_unpack_data(): Cannot generate srcname\n");
    return MS_GENERROR;
  }

  /* Read possible environmental variables that force byteorder */
  if (packheaderbyteorder == -2)
  {
    if ((envvariable = getenv ("PACK_HEADER_BYTEORDER")))
    {
      if (*envvariable != '0' && *envvariable != '1')
      {
        ms_log (2, "Environment variable PACK_HEADER_BYTEORDER must be set to '0' or '1'\n");
        return -1;
      }
      else if (*envvariable == '0')
      {
        packheaderbyteorder = 0;
        if (verbose > 2)
          ms_log (1, "PACK_HEADER_BYTEORDER=0, packing little-endian header\n");
      }
      else
      {
        packheaderbyteorder = 1;
        if (verbose > 2)
          ms_log (1, "PACK_HEADER_BYTEORDER=1, packing big-endian header\n");
      }
    }
    else
    {
      packheaderbyteorder = -1;
    }
  }

  if (msr->reclen < MINRECLEN || msr->reclen > MAXRECLEN)
  {
    ms_log (2, "msr_pack_header(%s): record length is out of range: %d\n",
            srcname, msr->reclen);
    return -1;
  }

  if (msr->byteorder != 0 && msr->byteorder != 1)
  {
    ms_log (2, "msr_pack_header(%s): byte order is not defined correctly: %d\n",
            srcname, msr->byteorder);
    return -1;
  }

  if (msr->fsdh)
  {
    maxheaderlen = (msr->fsdh->data_offset > 0) ? msr->fsdh->data_offset : msr->reclen;
  }
  else
  {
    maxheaderlen = msr->reclen;
  }

  /* Check to see if byte swapping is needed */
  if (msr->byteorder != ms_bigendianhost ())
    headerswapflag = 1;

  /* Check if byte order is forced */
  if (packheaderbyteorder >= 0)
  {
    headerswapflag = (msr->byteorder != packheaderbyteorder) ? 1 : 0;
  }

  if (verbose > 2)
  {
    if (headerswapflag)
      ms_log (1, "%s: Byte swapping needed for packing of header\n", srcname);
    else
      ms_log (1, "%s: Byte swapping NOT needed for packing of header\n", srcname);
  }

  headerlen = msr_pack_header_raw (msr, msr->record, maxheaderlen,
                                   headerswapflag, normalize, NULL,
                                   srcname, verbose);

  return headerlen;
} /* End of msr_pack_header() */

/***************************************************************************
 * msr_pack_header_raw:
 *
 * Pack data header/blockettes into the specified SEED data record.
 *
 * Returns the header length in bytes on success or -1 on error.
 ***************************************************************************/
static int
msr_pack_header_raw (MSRecord *msr, char *rawrec, int maxheaderlen,
                     flag swapflag, flag normalize,
                     struct blkt_1001_s **blkt1001,
                     char *srcname, flag verbose)
{
  struct blkt_link_s *cur_blkt;
  struct fsdh_s *fsdh;
  int16_t offset;
  int blktcnt = 0;
  int nextoffset;

  if (!msr || !rawrec)
    return -1;

  /* Make sure a fixed section of data header is available */
  if (!msr->fsdh)
  {
    msr->fsdh = (struct fsdh_s *)calloc (1, sizeof (struct fsdh_s));

    if (msr->fsdh == NULL)
    {
      ms_log (2, "msr_pack_header_raw(%s): Cannot allocate memory\n", srcname);
      return -1;
    }
  }

  /* Update the SEED structures associated with the MSRecord */
  if (normalize)
    if (msr_normalize_header (msr, verbose) < 0)
    {
      ms_log (2, "msr_pack_header_raw(%s): error normalizing header values\n", srcname);
      return -1;
    }

  if (verbose > 2)
    ms_log (1, "%s: Packing fixed section of data header\n", srcname);

  if (maxheaderlen > msr->reclen)
  {
    ms_log (2, "msr_pack_header_raw(%s): maxheaderlen of %d is beyond record length of %d\n",
            srcname, maxheaderlen, msr->reclen);
    return -1;
  }

  if (maxheaderlen < (int)sizeof (struct fsdh_s))
  {
    ms_log (2, "msr_pack_header_raw(%s): maxheaderlen of %d is too small, must be >= %d\n",
            srcname, maxheaderlen, sizeof (struct fsdh_s));
    return -1;
  }

  fsdh   = (struct fsdh_s *)rawrec;
  offset = 48;

  /* Roll-over sequence number if necessary */
  if (msr->sequence_number > 999999)
    msr->sequence_number = 1;

  /* Copy FSDH associated with the MSRecord into the record */
  memcpy (fsdh, msr->fsdh, sizeof (struct fsdh_s));

  /* Swap byte order? */
  if (swapflag)
  {
    MS_SWAPBTIME (&fsdh->start_time);
    ms_gswap2 (&fsdh->numsamples);
    ms_gswap2 (&fsdh->samprate_fact);
    ms_gswap2 (&fsdh->samprate_mult);
    ms_gswap4 (&fsdh->time_correct);
    ms_gswap2 (&fsdh->data_offset);
    ms_gswap2 (&fsdh->blockette_offset);
  }

  /* Traverse blockette chain and pack blockettes at 'offset' */
  cur_blkt = msr->blkts;

  while (cur_blkt && offset < maxheaderlen)
  {
    /* Check that the blockette fits */
    if ((offset + 4 + cur_blkt->blktdatalen) > maxheaderlen)
    {
      ms_log (2, "msr_pack_header_raw(%s): header exceeds maxheaderlen of %d\n",
              srcname, maxheaderlen);
      break;
    }

    /* Pack blockette type and leave space for next offset */
    memcpy (rawrec + offset, &cur_blkt->blkt_type, 2);
    if (swapflag)
      ms_gswap2 (rawrec + offset);
    nextoffset = offset + 2;
    offset += 4;

    if (cur_blkt->blkt_type == 100)
    {
      struct blkt_100_s *blkt_100 = (struct blkt_100_s *)(rawrec + offset);
      memcpy (blkt_100, cur_blkt->blktdata, sizeof (struct blkt_100_s));
      offset += sizeof (struct blkt_100_s);

      if (swapflag)
      {
        ms_gswap4 (&blkt_100->samprate);
      }
    }

    else if (cur_blkt->blkt_type == 200)
    {
      struct blkt_200_s *blkt_200 = (struct blkt_200_s *)(rawrec + offset);
      memcpy (blkt_200, cur_blkt->blktdata, sizeof (struct blkt_200_s));
      offset += sizeof (struct blkt_200_s);

      if (swapflag)
      {
        ms_gswap4 (&blkt_200->amplitude);
        ms_gswap4 (&blkt_200->period);
        ms_gswap4 (&blkt_200->background_estimate);
        MS_SWAPBTIME (&blkt_200->time);
      }
    }

    else if (cur_blkt->blkt_type == 201)
    {
      struct blkt_201_s *blkt_201 = (struct blkt_201_s *)(rawrec + offset);
      memcpy (blkt_201, cur_blkt->blktdata, sizeof (struct blkt_201_s));
      offset += sizeof (struct blkt_201_s);

      if (swapflag)
      {
        ms_gswap4 (&blkt_201->amplitude);
        ms_gswap4 (&blkt_201->period);
        ms_gswap4 (&blkt_201->background_estimate);
        MS_SWAPBTIME (&blkt_201->time);
      }
    }

    else if (cur_blkt->blkt_type == 300)
    {
      struct blkt_300_s *blkt_300 = (struct blkt_300_s *)(rawrec + offset);
      memcpy (blkt_300, cur_blkt->blktdata, sizeof (struct blkt_300_s));
      offset += sizeof (struct blkt_300_s);

      if (swapflag)
      {
        MS_SWAPBTIME (&blkt_300->time);
        ms_gswap4 (&blkt_300->step_duration);
        ms_gswap4 (&blkt_300->interval_duration);
        ms_gswap4 (&blkt_300->amplitude);
        ms_gswap4 (&blkt_300->reference_amplitude);
      }
    }

    else if (cur_blkt->blkt_type == 310)
    {
      struct blkt_310_s *blkt_310 = (struct blkt_310_s *)(rawrec + offset);
      memcpy (blkt_310, cur_blkt->blktdata, sizeof (struct blkt_310_s));
      offset += sizeof (struct blkt_310_s);

      if (swapflag)
      {
        MS_SWAPBTIME (&blkt_310->time);
        ms_gswap4 (&blkt_310->duration);
        ms_gswap4 (&blkt_310->period);
        ms_gswap4 (&blkt_310->amplitude);
        ms_gswap4 (&blkt_310->reference_amplitude);
      }
    }

    else if (cur_blkt->blkt_type == 320)
    {
      struct blkt_320_s *blkt_320 = (struct blkt_320_s *)(rawrec + offset);
      memcpy (blkt_320, cur_blkt->blktdata, sizeof (struct blkt_320_s));
      offset += sizeof (struct blkt_320_s);

      if (swapflag)
      {
        MS_SWAPBTIME (&blkt_320->time);
        ms_gswap4 (&blkt_320->duration);
        ms_gswap4 (&blkt_320->ptp_amplitude);
        ms_gswap4 (&blkt_320->reference_amplitude);
      }
    }

    else if (cur_blkt->blkt_type == 390)
    {
      struct blkt_390_s *blkt_390 = (struct blkt_390_s *)(rawrec + offset);
      memcpy (blkt_390, cur_blkt->blktdata, sizeof (struct blkt_390_s));
      offset += sizeof (struct blkt_390_s);

      if (swapflag)
      {
        MS_SWAPBTIME (&blkt_390->time);
        ms_gswap4 (&blkt_390->duration);
        ms_gswap4 (&blkt_390->amplitude);
      }
    }

    else if (cur_blkt->blkt_type == 395)
    {
      struct blkt_395_s *blkt_395 = (struct blkt_395_s *)(rawrec + offset);
      memcpy (blkt_395, cur_blkt->blktdata, sizeof (struct blkt_395_s));
      offset += sizeof (struct blkt_395_s);

      if (swapflag)
      {
        MS_SWAPBTIME (&blkt_395->time);
      }
    }

    else if (cur_blkt->blkt_type == 400)
    {
      struct blkt_400_s *blkt_400 = (struct blkt_400_s *)(rawrec + offset);
      memcpy (blkt_400, cur_blkt->blktdata, sizeof (struct blkt_400_s));
      offset += sizeof (struct blkt_400_s);

      if (swapflag)
      {
        ms_gswap4 (&blkt_400->azimuth);
        ms_gswap4 (&blkt_400->slowness);
        ms_gswap2 (&blkt_400->configuration);
      }
    }

    else if (cur_blkt->blkt_type == 405)
    {
      struct blkt_405_s *blkt_405 = (struct blkt_405_s *)(rawrec + offset);
      memcpy (blkt_405, cur_blkt->blktdata, sizeof (struct blkt_405_s));
      offset += sizeof (struct blkt_405_s);

      if (swapflag)
      {
        ms_gswap2 (&blkt_405->delay_values);
      }

      if (verbose > 0)
      {
        ms_log (1, "msr_pack_header_raw(%s): WARNING Blockette 405 cannot be fully supported\n",
                srcname);
      }
    }

    else if (cur_blkt->blkt_type == 500)
    {
      struct blkt_500_s *blkt_500 = (struct blkt_500_s *)(rawrec + offset);
      memcpy (blkt_500, cur_blkt->blktdata, sizeof (struct blkt_500_s));
      offset += sizeof (struct blkt_500_s);

      if (swapflag)
      {
        ms_gswap4 (&blkt_500->vco_correction);
        MS_SWAPBTIME (&blkt_500->time);
        ms_gswap4 (&blkt_500->exception_count);
      }
    }

    else if (cur_blkt->blkt_type == 1000)
    {
      struct blkt_1000_s *blkt_1000 = (struct blkt_1000_s *)(rawrec + offset);
      memcpy (blkt_1000, cur_blkt->blktdata, sizeof (struct blkt_1000_s));
      offset += sizeof (struct blkt_1000_s);

      /* This guarantees that the byte order is in sync with msr_pack() */
      if (packdatabyteorder >= 0)
        blkt_1000->byteorder = packdatabyteorder;
    }

    else if (cur_blkt->blkt_type == 1001)
    {
      struct blkt_1001_s *blkt_1001 = (struct blkt_1001_s *)(rawrec + offset);
      memcpy (blkt_1001, cur_blkt->blktdata, sizeof (struct blkt_1001_s));
      offset += sizeof (struct blkt_1001_s);

      /* Track location of Blockette 1001 if requested */
      if (blkt1001)
        *blkt1001 = blkt_1001;
    }

    else if (cur_blkt->blkt_type == 2000)
    {
      struct blkt_2000_s *blkt_2000 = (struct blkt_2000_s *)(rawrec + offset);
      memcpy (blkt_2000, cur_blkt->blktdata, cur_blkt->blktdatalen);
      offset += cur_blkt->blktdatalen;

      if (swapflag)
      {
        ms_gswap2 (&blkt_2000->length);
        ms_gswap2 (&blkt_2000->data_offset);
        ms_gswap4 (&blkt_2000->recnum);
      }

      /* Nothing done to pack the opaque headers and data, they should already
         be packed into the blockette payload */
    }

    else
    {
      memcpy (rawrec + offset, cur_blkt->blktdata, cur_blkt->blktdatalen);
      offset += cur_blkt->blktdatalen;
    }

    /* Pack the offset to the next blockette */
    if (cur_blkt->next)
    {
      memcpy (rawrec + nextoffset, &offset, 2);
      if (swapflag)
        ms_gswap2 (rawrec + nextoffset);
    }
    else
    {
      memset (rawrec + nextoffset, 0, 2);
    }

    blktcnt++;
    cur_blkt = cur_blkt->next;
  }

  fsdh->numblockettes = blktcnt;

  if (verbose > 2)
    ms_log (1, "%s: Packed %d blockettes\n", srcname, blktcnt);

  return offset;
} /* End of msr_pack_header_raw() */

/***************************************************************************
 * msr_update_header:
 *
 * Update the header values that change between records: start time,
 * sequence number, etc.
 *
 * Returns 0 on success or -1 on error.
 ***************************************************************************/
static int
msr_update_header (MSRecord *msr, char *rawrec, flag swapflag,
                   struct blkt_1001_s *blkt1001, char *srcname, flag verbose)
{
  struct fsdh_s *fsdh;
  hptime_t hptimems;
  int8_t usecoffset;
  char seqnum[7];

  if (!msr || !rawrec)
    return -1;

  if (verbose > 2)
    ms_log (1, "%s: Updating fixed section of data header\n", srcname);

  fsdh = (struct fsdh_s *)rawrec;

  /* Pack values into the fixed section of header */
  snprintf (seqnum, 7, "%06d", msr->sequence_number);
  memcpy (fsdh->sequence_number, seqnum, 6);

  /* Get start time rounded to tenths of milliseconds and microsecond offset */
  ms_hptime2tomsusecoffset (msr->starttime, &hptimems, &usecoffset);

  /* Update fixed-section start time */
  ms_hptime2btime (hptimems, &(fsdh->start_time));

  /* Swap byte order? */
  if (swapflag)
  {
    MS_SWAPBTIME (&fsdh->start_time);
  }

  /* Update microsecond offset value if Blockette 1001 is present */
  if (msr->Blkt1001 && blkt1001)
  {
    /* Update microseconds offset in blockette chain entry */
    msr->Blkt1001->usec = usecoffset;

    /* Update microseconds offset in packed header */
    blkt1001->usec = usecoffset;
  }

  return 0;
} /* End of msr_update_header() */

/************************************************************************
 *  msr_pack_data:
 *
 *  Pack Mini-SEED data samples.  The input data samples specified as
 *  'src' will be packed with 'encoding' format and placed in 'dest'.
 *
 *  If a pointer to a 32-bit integer sample is provided in the
 *  argument 'lastintsample' and 'comphistory' is true the sample
 *  value will be used to seed the difference buffer for Steim1/2
 *  encoding and provide a compression history.  It will also be
 *  updated with the last sample packed in order to be used with a
 *  subsequent call to this routine.
 *
 *  Return number of samples packed on success and a negative on error.
 ************************************************************************/
static int
msr_pack_data (void *dest, void *src, int maxsamples, int maxdatabytes,
               int32_t *lastintsample, flag comphistory, char sampletype,
               flag encoding, flag swapflag, char *srcname, flag verbose)
{
  int nsamples;
  int32_t *intbuff;
  int32_t d0;

  /* Check for encode debugging environment variable */
  if (getenv ("ENCODE_DEBUG"))
    encodedebug = 1;

  /* Decide if this is a format that we can encode */
  switch (encoding)
  {
  case DE_ASCII:
    if (sampletype != 'a')
    {
      ms_log (2, "%s: Sample type must be ascii (a) for ASCII text encoding not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    if (verbose > 1)
      ms_log (1, "%s: Packing ASCII data\n", srcname);

    nsamples = msr_encode_text (src, maxsamples, dest, maxdatabytes);

    break;

  case DE_INT16:
    if (sampletype != 'i')
    {
      ms_log (2, "%s: Sample type must be integer (i) for INT16 encoding not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    if (verbose > 1)
      ms_log (1, "%s: Packing INT16 data samples\n", srcname);

    nsamples = msr_encode_int16 (src, maxsamples, dest, maxdatabytes, swapflag);

    break;

  case DE_INT32:
    if (sampletype != 'i')
    {
      ms_log (2, "%s: Sample type must be integer (i) for INT32 encoding not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    if (verbose > 1)
      ms_log (1, "%s: Packing INT32 data samples\n", srcname);

    nsamples = msr_encode_int32 (src, maxsamples, dest, maxdatabytes, swapflag);

    break;

  case DE_FLOAT32:
    if (sampletype != 'f')
    {
      ms_log (2, "%s: Sample type must be float (f) for FLOAT32 encoding not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    if (verbose > 1)
      ms_log (1, "%s: Packing FLOAT32 data samples\n", srcname);

    nsamples = msr_encode_float32 (src, maxsamples, dest, maxdatabytes, swapflag);

    break;

  case DE_FLOAT64:
    if (sampletype != 'd')
    {
      ms_log (2, "%s: Sample type must be double (d) for FLOAT64 encoding not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    if (verbose > 1)
      ms_log (1, "%s: Packing FLOAT64 data samples\n", srcname);

    nsamples = msr_encode_float64 (src, maxsamples, dest, maxdatabytes, swapflag);

    break;

  case DE_STEIM1:
    if (sampletype != 'i')
    {
      ms_log (2, "%s: Sample type must be integer (i) for Steim1 compression not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    intbuff = (int32_t *)src;

    /* If a previous sample is supplied use it for compression history otherwise cold-start */
    d0 = (lastintsample && comphistory) ? (intbuff[0] - *lastintsample) : 0;

    if (verbose > 1)
      ms_log (1, "%s: Packing Steim1 data frames\n", srcname);

    nsamples = msr_encode_steim1 (src, maxsamples, dest, maxdatabytes, d0, swapflag);

    /* If a previous sample is supplied update it with the last sample value */
    if (lastintsample && nsamples > 0)
      *lastintsample = intbuff[nsamples - 1];

    break;

  case DE_STEIM2:
    if (sampletype != 'i')
    {
      ms_log (2, "%s: Sample type must be integer (i) for Steim2 compression not '%c'\n",
              srcname, sampletype);
      return -1;
    }

    intbuff = (int32_t *)src;

    /* If a previous sample is supplied use it for compression history otherwise cold-start */
    d0 = (lastintsample && comphistory) ? (intbuff[0] - *lastintsample) : 0;

    if (verbose > 1)
      ms_log (1, "%s: Packing Steim2 data frames\n", srcname);

    nsamples = msr_encode_steim2 (src, maxsamples, dest, maxdatabytes, d0, srcname, swapflag);

    /* If a previous sample is supplied update it with the last sample value */
    if (lastintsample && nsamples > 0)
      *lastintsample = intbuff[nsamples - 1];

    break;

  default:
    ms_log (2, "%s: Unable to pack format %d\n", srcname, encoding);

    return -1;
  }

  return nsamples;
} /* End of msr_pack_data() */