Fossil with Commonmark

    blob_append(&expr, zEnd, -1);
    return blob_str(&expr);
  }

  /* If execution reaches this point, the pattern was empty.  Return NULL. */
  return 0;
}

/*
** Add SQL text to the WHERE clause expression in pCond that restricts
** the timeline to elements of the zTagSql tag or branch.  In other words,
** handle the r= and t= query parameters.
**
** zTagSql is an SQL expression that identifies the tags to be displayed.
** If zTagSql is NULL, this routine is a no-op.
**
** If the "related" flag is set, the first check-in before and after the
** branch is also shown.  If related==0, then only the specified tag or
** branch is shown.
*/
static void timeline_tag_or_branch_conditional(
  const char *zTagSql,    /* SQL expression for the tag or branch to display */
  Blob *pCond,            /* WHERE clause under construction */
  int related,            /* TRUE to show related check-ins */
  int tmFlags             /* Other timeline flags */
){
  if( zTagSql ){
    blob_append_sql(pCond,
      " AND (EXISTS(SELECT 1 FROM tagxref NATURAL JOIN tag"
      " WHERE %s AND tagtype>0 AND rid=blob.rid)\n", zTagSql/*safe-for-%s*/);

    if( related ){
      /* The next two blob_appendf() calls add SQL that causes check-ins that
      ** are not part of the branch which are parents or children of the
      ** branch to be included in the report.  This related check-ins are
      ** useful in helping to visualize what has happened on a quiescent
      ** branch that is infrequently merged with a much more activate branch.
      */
      blob_append_sql(pCond,
        " OR EXISTS(SELECT 1 FROM plink CROSS JOIN tagxref ON rid=cid"
        " NATURAL JOIN tag WHERE %s AND tagtype>0 AND pid=blob.rid)\n",
         zTagSql/*safe-for-%s*/
      );
      if( (tmFlags & TIMELINE_UNHIDE)==0 ){
        blob_append_sql(pCond,
          " AND NOT EXISTS(SELECT 1 FROM plink JOIN tagxref ON rid=cid"
                     " WHERE tagid=%d AND tagtype>0 AND pid=blob.rid)\n",
          TAG_HIDDEN
        );
      }
      if( P("mionly")==0 ){
        blob_append_sql(pCond,
          " OR EXISTS(SELECT 1 FROM plink CROSS JOIN tagxref ON rid=pid"
          " NATURAL JOIN tag WHERE %s AND tagtype>0 AND cid=blob.rid)\n",
          zTagSql/*safe-for-%s*/
        );
        if( (tmFlags & TIMELINE_UNHIDE)==0 ){
          blob_append_sql(pCond,
            " AND NOT EXISTS(SELECT 1 FROM plink JOIN tagxref ON rid=pid"
            " WHERE tagid=%d AND tagtype>0 AND cid=blob.rid)\n",
            TAG_HIDDEN
          );
        }
      }
    }
    blob_append_sql(pCond, ")");
  }
}

/*
** WEBPAGE: timeline
**
** Query parameters:
**
**    a=TIMEORTAG     After this event

    }
    db_multi_exec(
       "CREATE TEMP TABLE IF NOT EXISTS ok(rid INTEGER PRIMARY KEY)"
    );
    zUuid = db_text("", "SELECT uuid FROM blob WHERE rid=%d",
                         p_rid ? p_rid : d_rid);
    blob_append_sql(&sql, " AND event.objid IN ok");
    timeline_tag_or_branch_conditional(zTagSql, &sql, related, tmFlags);
    nd = 0;
    if( d_rid ){
      compute_descendants(d_rid, nEntry+1);
      nd = db_int(0, "SELECT count(*)-1 FROM ok");
      if( nd>=0 ) db_multi_exec("%s", blob_sql_text(&sql));
      if( nd>0 ) blob_appendf(&desc, "%d descendant%s", nd,(1==nd)?"":"s");
      if( useDividers ) selectedRid = d_rid;

      blob_append_sql(&cond, " AND %Q=strftime('%%Y-%%W',event.mtime) ",
                   zYearWeek);
    }
    else if( zDay ){
      blob_append_sql(&cond, " AND %Q=strftime('%%Y-%%m-%%d',event.mtime) ",
                   zDay);
    }




    timeline_tag_or_branch_conditional(zTagSql, &cond, related, tmFlags);




































    if( (zType[0]=='w' && !g.perm.RdWiki)
     || (zType[0]=='t' && !g.perm.RdTkt)
     || (zType[0]=='e' && !g.perm.RdWiki)
     || (zType[0]=='c' && !g.perm.Read)
     || (zType[0]=='g' && !g.perm.Read)
    ){
      zType = "all";