selection.c

/***************************************************************************
 * selection.c:
 *
 * Generic routines to manage selection lists.
 *
 * Written by Chad Trabant unless otherwise noted
 *   IRIS Data Management Center
 *
 * modified: 2014.197
 ***************************************************************************/

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

#include "libmseed.h"

static int ms_globmatch (char *string, char *pattern);

/***************************************************************************
 * ms_matchselect:
 *
 * Test the specified parameters for a matching selection entry.  The
 * srcname parameter may contain globbing characters.  The NULL value
 * (matching any times) for the start and end times is HPTERROR.
 *
 * Return Selections pointer to matching entry on successful match and
 * NULL for no match or error.
 ***************************************************************************/
Selections *
ms_matchselect (Selections *selections, char *srcname, hptime_t starttime,
                hptime_t endtime, SelectTime **ppselecttime)
{
  Selections *findsl  = NULL;
  SelectTime *findst  = NULL;
  SelectTime *matchst = NULL;

  if (selections)
  {
    findsl = selections;
    while (findsl)
    {
      if (ms_globmatch (srcname, findsl->srcname))
      {
        findst = findsl->timewindows;
        while (findst)
        {
          if (starttime != HPTERROR && findst->starttime != HPTERROR &&
              (starttime < findst->starttime && !(starttime <= findst->starttime && endtime >= findst->starttime)))
          {
            findst = findst->next;
            continue;
          }
          else if (endtime != HPTERROR && findst->endtime != HPTERROR &&
                   (endtime > findst->endtime && !(starttime <= findst->endtime && endtime >= findst->endtime)))
          {
            findst = findst->next;
            continue;
          }

          matchst = findst;
          break;
        }
      }

      if (matchst)
        break;
      else
        findsl = findsl->next;
    }
  }

  if (ppselecttime)
    *ppselecttime = matchst;

  return (matchst) ? findsl : NULL;
} /* End of ms_matchselect() */

/***************************************************************************
 * msr_matchselect:
 *
 * A simple wrapper for calling ms_matchselect() using details from a
 * MSRecord struct.
 *
 * Return Selections pointer to matching entry on successful match and
 * NULL for no match or error.
 ***************************************************************************/
Selections *
msr_matchselect (Selections *selections, MSRecord *msr, SelectTime **ppselecttime)
{
  char srcname[50];
  hptime_t endtime;

  if (!selections || !msr)
    return NULL;

  msr_srcname (msr, srcname, 1);
  endtime = msr_endtime (msr);

  return ms_matchselect (selections, srcname, msr->starttime, endtime,
                         ppselecttime);
} /* End of msr_matchselect() */

/***************************************************************************
 * ms_addselect:
 *
 * Add select parameters to a specified selection list.  The srcname
 * argument may contain globbing parameters.  The NULL value (matching
 * any value) for the start and end times is HPTERROR.
 *
 * Return 0 on success and -1 on error.
 ***************************************************************************/
int
ms_addselect (Selections **ppselections, char *srcname,
              hptime_t starttime, hptime_t endtime)
{
  Selections *newsl = NULL;
  SelectTime *newst = NULL;

  if (!ppselections || !srcname)
    return -1;

  /* Allocate new SelectTime and populate */
  if (!(newst = (SelectTime *)calloc (1, sizeof (SelectTime))))
  {
    ms_log (2, "Cannot allocate memory\n");
    return -1;
  }

  newst->starttime = starttime;
  newst->endtime   = endtime;

  /* Add new Selections struct to begining of list */
  if (!*ppselections)
  {
    /* Allocate new Selections and populate */
    if (!(newsl = (Selections *)calloc (1, sizeof (Selections))))
    {
      ms_log (2, "Cannot allocate memory\n");
      return -1;
    }

    strncpy (newsl->srcname, srcname, sizeof (newsl->srcname));
    newsl->srcname[sizeof (newsl->srcname) - 1] = '\0';

    /* Add new Selections struct as first in list */
    *ppselections      = newsl;
    newsl->timewindows = newst;
  }
  else
  {
    Selections *findsl  = *ppselections;
    Selections *matchsl = 0;

    /* Search for matching Selectlink entry */
    while (findsl)
    {
      if (!strcmp (findsl->srcname, srcname))
      {
        matchsl = findsl;
        break;
      }

      findsl = findsl->next;
    }

    if (matchsl)
    {
      /* Add time window selection to beginning of window list */
      newst->next          = matchsl->timewindows;
      matchsl->timewindows = newst;
    }
    else
    {
      /* Allocate new Selections and populate */
      if (!(newsl = (Selections *)calloc (1, sizeof (Selections))))
      {
        ms_log (2, "Cannot allocate memory\n");
        return -1;
      }

      strncpy (newsl->srcname, srcname, sizeof (newsl->srcname));
      newsl->srcname[sizeof (newsl->srcname) - 1] = '\0';

      /* Add new Selections to beginning of list */
      newsl->next        = *ppselections;
      *ppselections      = newsl;
      newsl->timewindows = newst;
    }
  }

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

/***************************************************************************
 * ms_addselect_comp:
 *
 * Add select parameters to a specified selection list based on
 * separate name components.  The network, station, location, channel
 * and quality arguments may contain globbing parameters.  The NULL
 * value (matching any value) for the start and end times is HPTERROR.
 *
 * If any of the naming parameters are not supplied (pointer is NULL)
 * a wildcard for all matches is substituted.  As a special case, if
 * the location ID (loc) is set to "--" to match a space-space/blank
 * ID it will be translated to an empty string to match libmseed's
 * notation.
 *
 * Return 0 on success and -1 on error.
 ***************************************************************************/
int
ms_addselect_comp (Selections **ppselections, char *net, char *sta, char *loc,
                   char *chan, char *qual, hptime_t starttime, hptime_t endtime)
{
  char srcname[100];
  char selnet[20];
  char selsta[20];
  char selloc[20];
  char selchan[20];
  char selqual[20];

  if (!ppselections)
    return -1;

  if (net)
  {
    strncpy (selnet, net, sizeof (selnet));
    selnet[sizeof (selnet) - 1] = '\0';
  }
  else
    strcpy (selnet, "*");

  if (sta)
  {
    strncpy (selsta, sta, sizeof (selsta));
    selsta[sizeof (selsta) - 1] = '\0';
  }
  else
    strcpy (selsta, "*");

  if (loc)
  {
    /* Test for special case blank location ID */
    if (!strcmp (loc, "--"))
      selloc[0] = '\0';
    else
    {
      strncpy (selloc, loc, sizeof (selloc));
      selloc[sizeof (selloc) - 1] = '\0';
    }
  }
  else
    strcpy (selloc, "*");

  if (chan)
  {
    strncpy (selchan, chan, sizeof (selchan));
    selchan[sizeof (selchan) - 1] = '\0';
  }
  else
    strcpy (selchan, "*");

  if (qual)
  {
    strncpy (selqual, qual, sizeof (selqual));
    selqual[sizeof (selqual) - 1] = '\0';
  }
  else
    strcpy (selqual, "?");

  /* Create the srcname globbing match for this entry */
  snprintf (srcname, sizeof (srcname), "%s_%s_%s_%s_%s",
            selnet, selsta, selloc, selchan, selqual);

  /* Add selection to list */
  if (ms_addselect (ppselections, srcname, starttime, endtime))
    return -1;

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

/***************************************************************************
 * ms_readselectionsfile:
 *
 * Read a list of data selections from a file and them to the
 * specified selections list.  On errors this routine will leave
 * allocated memory unreachable (leaked), it is expected that this is
 * a program failing condition.
 *
 * As a special case if the filename is "-", selection lines will be
 * read from stdin.
 *
 * Returns count of selections added on success and -1 on error.
 ***************************************************************************/
int
ms_readselectionsfile (Selections **ppselections, char *filename)
{
  FILE *fp;
  hptime_t starttime;
  hptime_t endtime;
  char selectline[200];
  char *selnet;
  char *selsta;
  char *selloc;
  char *selchan;
  char *selqual;
  char *selstart;
  char *selend;
  char *cp;
  char next;
  int selectcount = 0;
  int linecount   = 0;

  if (!ppselections || !filename)
    return -1;

  if (strcmp (filename, "-"))
  {
    if (!(fp = fopen (filename, "rb")))
    {
      ms_log (2, "Cannot open file %s: %s\n", filename, strerror (errno));
      return -1;
    }
  }
  else
  {
    /* Use stdin as special case */
    fp = stdin;
  }

  while (fgets (selectline, sizeof (selectline) - 1, fp))
  {
    selnet   = 0;
    selsta   = 0;
    selloc   = 0;
    selchan  = 0;
    selqual  = 0;
    selstart = 0;
    selend   = 0;

    linecount++;

    /* Guarantee termination */
    selectline[sizeof (selectline) - 1] = '\0';

    /* End string at first newline character if any */
    if ((cp = strchr (selectline, '\n')))
      *cp = '\0';

    /* Skip empty lines */
    if (!strlen (selectline))
      continue;

    /* Skip comment lines */
    if (*selectline == '#')
      continue;

    /* Parse: identify components of selection and terminate */
    cp   = selectline;
    next = 1;
    while (*cp)
    {
      if (*cp == ' ' || *cp == '\t')
      {
        *cp  = '\0';
        next = 1;
      }
      else if (*cp == '#')
      {
        *cp = '\0';
        break;
      }
      else if (next && !selnet)
      {
        selnet = cp;
        next   = 0;
      }
      else if (next && !selsta)
      {
        selsta = cp;
        next   = 0;
      }
      else if (next && !selloc)
      {
        selloc = cp;
        next   = 0;
      }
      else if (next && !selchan)
      {
        selchan = cp;
        next    = 0;
      }
      else if (next && !selqual)
      {
        selqual = cp;
        next    = 0;
      }
      else if (next && !selstart)
      {
        selstart = cp;
        next     = 0;
      }
      else if (next && !selend)
      {
        selend = cp;
        next   = 0;
      }
      else if (next)
      {
        *cp = '\0';
        break;
      }
      cp++;
    }

    /* Skip line if network, station, location and channel are not defined */
    if (!selnet || !selsta || !selloc || !selchan)
    {
      ms_log (2, "[%s] Skipping data selection line number %d\n", filename, linecount);
      continue;
    }

    if (selstart)
    {
      starttime = ms_seedtimestr2hptime (selstart);
      if (starttime == HPTERROR)
      {
        ms_log (2, "Cannot convert data selection start time (line %d): %s\n", linecount, selstart);
        return -1;
      }
    }
    else
    {
      starttime = HPTERROR;
    }

    if (selend)
    {
      endtime = ms_seedtimestr2hptime (selend);
      if (endtime == HPTERROR)
      {
        ms_log (2, "Cannot convert data selection end time (line %d): %s\n", linecount, selend);
        return -1;
      }
    }
    else
    {
      endtime = HPTERROR;
    }

    /* Add selection to list */
    if (ms_addselect_comp (ppselections, selnet, selsta, selloc, selchan, selqual, starttime, endtime))
    {
      ms_log (2, "[%s] Error adding selection on line %d\n", filename, linecount);
      return -1;
    }

    selectcount++;
  }

  if (fp != stdin)
    fclose (fp);

  return selectcount;
} /* End of ms_readselectionsfile() */

/***************************************************************************
 * ms_freeselections:
 *
 * Free all memory associated with a Selections struct.
 ***************************************************************************/
void
ms_freeselections (Selections *selections)
{
  Selections *select;
  Selections *selectnext;
  SelectTime *selecttime;
  SelectTime *selecttimenext;

  if (selections)
  {
    select = selections;

    while (select)
    {
      selectnext = select->next;

      selecttime = select->timewindows;

      while (selecttime)
      {
        selecttimenext = selecttime->next;

        free (selecttime);

        selecttime = selecttimenext;
      }

      free (select);

      select = selectnext;
    }
  }

} /* End of ms_freeselections() */

/***************************************************************************
 * ms_printselections:
 *
 * Print the selections list using the ms_log() facility.
 ***************************************************************************/
void
ms_printselections (Selections *selections)
{
  Selections *select;
  SelectTime *selecttime;
  char starttime[50];
  char endtime[50];

  if (!selections)
    return;

  select = selections;
  while (select)
  {
    ms_log (0, "Selection: %s\n", select->srcname);

    selecttime = select->timewindows;
    while (selecttime)
    {
      if (selecttime->starttime != HPTERROR)
        ms_hptime2seedtimestr (selecttime->starttime, starttime, 1);
      else
        strncpy (starttime, "No start time", sizeof (starttime) - 1);

      if (selecttime->endtime != HPTERROR)
        ms_hptime2seedtimestr (selecttime->endtime, endtime, 1);
      else
        strncpy (endtime, "No end time", sizeof (endtime) - 1);

      ms_log (0, "  %30s  %30s\n", starttime, endtime);

      selecttime = selecttime->next;
    }

    select = select->next;
  }
} /* End of ms_printselections() */

/***********************************************************************
 * robust glob pattern matcher
 * ozan s. yigit/dec 1994
 * public domain
 *
 * glob patterns:
 *	*	matches zero or more characters
 *	?	matches any single character
 *	[set]	matches any character in the set
 *	[^set]	matches any character NOT in the set
 *		where a set is a group of characters or ranges. a range
 *		is written as two characters seperated with a hyphen: a-z denotes
 *		all characters between a to z inclusive.
 *	[-set]	set matches a literal hypen and any character in the set
 *	[]set]	matches a literal close bracket and any character in the set
 *
 *	char	matches itself except where char is '*' or '?' or '['
 *	\char	matches char, including any pattern character
 *
 * examples:
 *	a*c		ac abc abbc ...
 *	a?c		acc abc aXc ...
 *	a[a-z]c		aac abc acc ...
 *	a[-a-z]c	a-c aac abc ...
 *
 * Revision 1.4  2004/12/26  12:38:00  ct
 * Changed function name (amatch -> globmatch), variables and
 * formatting for clarity.  Also add matching header globmatch.h.
 *
 * Revision 1.3  1995/09/14  23:24:23  oz
 * removed boring test/main code.
 *
 * Revision 1.2  94/12/11  10:38:15  oz
 * charset code fixed. it is now robust and interprets all
 * variations of charset [i think] correctly, including [z-a] etc.
 * 
 * Revision 1.1  94/12/08  12:45:23  oz
 * Initial revision
 ***********************************************************************/

#define GLOBMATCH_TRUE 1
#define GLOBMATCH_FALSE 0
#define GLOBMATCH_NEGATE '^' /* std char set negation char */

/***********************************************************************
 * ms_globmatch:
 *
 * Check if a string matches a globbing pattern.
 *
 * Return 0 if string does not match pattern and non-zero otherwise.
 **********************************************************************/
static int
ms_globmatch (char *string, char *pattern)
{
  int negate;
  int match;
  int c;

  while (*pattern)
  {
    if (!*string && *pattern != '*')
      return GLOBMATCH_FALSE;

    switch (c = *pattern++)
    {

    case '*':
      while (*pattern == '*')
        pattern++;

      if (!*pattern)
        return GLOBMATCH_TRUE;

      if (*pattern != '?' && *pattern != '[' && *pattern != '\\')
        while (*string && *pattern != *string)
          string++;

      while (*string)
      {
        if (ms_globmatch (string, pattern))
          return GLOBMATCH_TRUE;
        string++;
      }
      return GLOBMATCH_FALSE;

    case '?':
      if (*string)
        break;
      return GLOBMATCH_FALSE;

    /* set specification is inclusive, that is [a-z] is a, z and
	   * everything in between. this means [z-a] may be interpreted
	   * as a set that contains z, a and nothing in between.
	   */
    case '[':
      if (*pattern != GLOBMATCH_NEGATE)
        negate = GLOBMATCH_FALSE;
      else
      {
        negate = GLOBMATCH_TRUE;
        pattern++;
      }

      match = GLOBMATCH_FALSE;

      while (!match && (c = *pattern++))
      {
        if (!*pattern)
          return GLOBMATCH_FALSE;

        if (*pattern == '-') /* c-c */
        {
          if (!*++pattern)
            return GLOBMATCH_FALSE;
          if (*pattern != ']')
          {
            if (*string == c || *string == *pattern ||
                (*string > c && *string < *pattern))
              match = GLOBMATCH_TRUE;
          }
          else
          { /* c-] */
            if (*string >= c)
              match = GLOBMATCH_TRUE;
            break;
          }
        }
        else /* cc or c] */
        {
          if (c == *string)
            match = GLOBMATCH_TRUE;
          if (*pattern != ']')
          {
            if (*pattern == *string)
              match = GLOBMATCH_TRUE;
          }
          else
            break;
        }
      }

      if (negate == match)
        return GLOBMATCH_FALSE;

      /* If there is a match, skip past the charset and continue on */
      while (*pattern && *pattern != ']')
        pattern++;
      if (!*pattern++) /* oops! */
        return GLOBMATCH_FALSE;
      break;

    case '\\':
      if (*pattern)
        c = *pattern++;
    default:
      if (c != *string)
        return GLOBMATCH_FALSE;
      break;
    }

    string++;
  }

  return !*string;
} /* End of ms_globmatch() */