diplodocus.org Git - nmh/blob - sbr/seq_list.c

   1
   2 /*
   3  * seq_list.c -- Get all messages in a sequence and return them
   4  *            -- as a space separated list of message ranges.
   5  *
   6  * $Id$
   7  *
   8  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   9  * COPYRIGHT file in the root directory of the nmh distribution for
  10  * complete copyright information.
  11  */
  12
  13 #include <h/mh.h>
  14
  15 /* allocate this much buffer space at a time */
  16 #define MAXBUFFER 1024
  17
  18 /* static buffer to collect the sequence line */
  19 static char *buffer = NULL;
  20 static int len = 0;
  21
  22
  23 char *
  24 seq_list(struct msgs *mp, char *seqname)
  25 {
  26     int i, j, seqnum;
  27     char *bp;
  28
  29     /* On first invocation, allocate initial buffer space */
  30     if (!buffer) {
  31         len = MAXBUFFER;
  32         if (!(buffer = malloc ((size_t) len)))
  33             adios (NULL, "unable to malloc storage in seq_list");
  34     }
  35
  36     /*
  37      * Special processing for "cur" sequence.  We assume that the
  38      * "cur" sequence and mp->curmsg are in sync (see seq_add.c).
  39      * This is returned, even if message doesn't exist or the
  40      * folder is empty.
  41      */
  42     if (!strcmp (current, seqname)) {
  43         if (mp->curmsg) {
  44             sprintf(buffer, "%s", m_name(mp->curmsg));
  45             return (buffer);
  46         } else
  47             return (NULL);
  48     }
  49
  50     /* If the folder is empty, just return NULL */
  51     if (mp->nummsg == 0)
  52         return NULL;
  53
  54     /* Get the index of the sequence */
  55     if ((seqnum = seq_getnum (mp, seqname)) == -1)
  56         return NULL;
  57
  58     bp = buffer;
  59
  60     for (i = mp->lowmsg; i <= mp->hghmsg; ++i) {
  61         /*
  62          * If message doesn't exist, or isn't in
  63          * the sequence, then continue.
  64          */
  65         if (!does_exist(mp, i) || !in_sequence(mp, seqnum, i))
  66             continue;
  67
  68         /*
  69          * See if we need to enlarge buffer.  Since we don't know
  70          * exactly how many character this particular message range
  71          * will need, we enlarge the buffer if we are within
  72          * 50 characters of the end.
  73          */
  74         if (bp - buffer > len - 50) {
  75             char *newbuf;
  76
  77             len += MAXBUFFER;
  78             if (!(newbuf = realloc (buffer, (size_t) len)))
  79                 adios (NULL, "unable to realloc storage in seq_list");
  80             bp = newbuf + (bp - buffer);
  81             buffer = newbuf;
  82         }
  83
  84         /*
  85          * If this is not the first message range in
  86          * the list, first add a space.
  87          */
  88         if (bp > buffer)
  89             *bp++ = ' ';
  90
  91         sprintf(bp, "%s", m_name(i));
  92         bp += strlen(bp);
  93         j = i;                  /* Remember beginning of message range */
  94
  95         /*
  96          * Scan to the end of this message range
  97          */
  98         for (++i; i <= mp->hghmsg && does_exist(mp, i) && in_sequence(mp, seqnum, i);
  99              ++i)
 100             ;
 101
 102         if (i - j > 1) {
 103             sprintf(bp, "-%s", m_name(i - 1));
 104             bp += strlen(bp);
 105         }
 106     }
 107     return (bp > buffer? buffer : NULL);
 108 }