4.3BSD - /usr/ingres/source/iutil/gettree.c

   1: # include   <ingres.h>
   2: # include   <catalog.h>
   3: # include   <tree.h>
   4: # include   <symbol.h>
   5: # include   <sccs.h>
   6: 
   7: SCCSID(@(#)gettree.c	8.2	1/15/85)
   8: 
   9: 
  10: /*
  11: **  GETTREE -- get tree from 'tree' catalog
  12: **
  13: **	This function, given an internal treeid, fetches and builds
  14: **	that tree from the 'tree' catalog.  There is nothing exciting
  15: **	except the mapping of variables, done by mapvars().
  16: **
  17: **	Parameters:
  18: **		treeid -- internal id of tree to fetch and build.
  19: **		init -- passed to 'readqry' to tell whether or not
  20: **			to initialize the query buffer.
  21: **
  22: **	Returns:
  23: **		Pointer to root of tree.
  24: **
  25: **	Side Effects:
  26: **		file activity.  Space in Qbuf is used up.
  27: **
  28: **	Trace Flags:
  29: **		13
  30: */
  31: 
  32: QTREE *
  33: gettree(treerelid, treeowner, treetype, treeid, init)
  34: char    *treerelid;
  35: char    *treeowner;
  36: char    treetype;
  37: int treeid;
  38: int init;
  39: {
  40:     register QTREE  *t;
  41:     extern int  relntrrd();
  42:     register int    i;
  43:     extern QTREE    *readqry();
  44: 
  45:     /* initialize relntrrd() for this treeid */
  46:     relntrrd(0, NULL, 0, treerelid, treeowner, treetype, treeid);
  47: 
  48:     /* read and build query tree */
  49:     t = readqry(relntrrd, 0, init);
  50: 
  51:     /* remap varno's to be unique */
  52:     if (!init)
  53:         mapvars(t);
  54: 
  55:     return (t);
  56: }
  57: /*
  58: **  RELNTRRD -- read tree from 'tree' relation
  59: **
  60: **	This looks exactly like the 'pipetrrd' call, except that info
  61: **	comes from the 'tree' talolog instead of from the pipe.  It
  62: **	must be initialized by calling it with a NULL pointer and
  63: **	the segment name wanted as 'treeid'.
  64: **
  65: **	Parameters:
  66: **		dummyx -- a placeholder parameter to make this
  67: **			routine compatible with pb_get.
  68: **		ptr -- NULL -- "initialize".
  69: **			else -- pointer to read area.
  70: **		cnt -- count of number of bytes to read.
  71: **		treerelid -- if ptr == NULL, the relation name
  72: **			associated with the tree; ignored otherwise.
  73: **		treeowner -- if ptr == NULL, the owner of the relation
  74: **			associated with the tree; ignored otherwise.
  75: **		treetype -- if ptr == NULL, the type of the tree
  76: **			(view, prot, etc.); ignored otherwise.
  77: **		treeid -- if ptr == NULL, this is the tree id,
  78: **			otherwise this parameter is not supplied.
  79: **
  80: **	Returns:
  81: **		count of actual number of bytes read.
  82: **
  83: **	Side Effects:
  84: **		activity in database.
  85: **		static variables are adjusted correctly.  Note that
  86: **			this routine can be used on only one tree
  87: **			at one time.
  88: */
  89: 
  90: relntrrd(dummyx, ptr, cnt, treerelid, treeowner, treetype, treeid)
  91: char    *ptr;
  92: int cnt;
  93: char    *treerelid;
  94: char    *treeowner;
  95: char    treetype;
  96: int treeid;
  97: {
  98:     static struct tree  trseg;
  99:     static char     *trp;
 100:     static short        seqno;
 101:     static  int     bytesleft;
 102:     register char       *p;
 103:     register int        n;
 104:     register int        i;
 105:     struct tree     trkey;
 106:     TID         tid;
 107:     extern DESC     Treedes;
 108: 
 109:     p = ptr;
 110:     n = cnt;
 111: 
 112:     if (p == NULL)
 113:     {
 114:         /* initialize -- make buffer appear empty */
 115:         trp = &trseg.treetree[sizeof trseg.treetree];
 116:         bytesleft = 0;
 117:         bmove(treerelid, trseg.treerelid, MAXNAME);
 118:         bmove(treeowner, trseg.treeowner, 2);
 119:         trseg.treetype = treetype;
 120:         trseg.treeid = treeid;
 121:         seqno = 0;
 122:         opencatalog("tree", OR_READ);
 123: 
 124: #		ifdef xQTR2
 125:         if (tTf(13, 6))
 126:             printf("relntrrd: n=%.12s o=%.2s t=%d i=%d\n",
 127:                 treerelid, treeowner, treetype, treeid);
 128: #		endif
 129: 
 130:         return (0);
 131:     }
 132: 
 133:     /* fetch characters */
 134:     while (n-- > 0)
 135:     {
 136:         /* check for segment empty */
 137:         if ( bytesleft == 0 )
 138:         {
 139:             /* then read new segment */
 140:             clearkeys(&Treedes);
 141:             setkey(&Treedes, &trkey, trseg.treerelid, TREERELID);
 142:             setkey(&Treedes, &trkey, trseg.treeowner, TREEOWNER);
 143:             setkey(&Treedes, &trkey, &trseg.treetype, TREETYPE);
 144:             setkey(&Treedes, &trkey, &trseg.treeid, TREEID);
 145:             setkey(&Treedes, &trkey, &seqno, TREESEQ);
 146:             seqno++;
 147:             if ((i = getequal(&Treedes, &trkey, &trseg, &tid)) != 0)
 148:                 syserr("relnrdtr: getequal %d", i);
 149:             trp = &trseg.treetree[0];
 150:             bytesleft = sizeof (trseg.treetree);
 151:         }
 152: 
 153:         /* do actual character fetch */
 154:         *p++ = *trp++;
 155:         bytesleft--;
 156:     }
 157: 
 158:     return (cnt);
 159: }

Defined functions