Fossil

#include <assert.h>


/*
** Create a temporary table named "leaves" if it does not
** already exist.  Load this table with the RID of all
** check-ins that are leaves which are decended from
** check-in iBase.  If iBase==0, find all leaves within the
** entire check-in hierarchy.
**
** A "leaf" is a check-in that has no children in the same branch.
**
** The closeMode flag determines behavior associated with the "closed"
** tag:
**
**    closeMode==0       Show all leaves regardless of the "closed" tag.
**
**    closeMode==1       Show only leaves without the "closed" tag.
**
**    closeMode==2       Show only leaves with the "closed" tag.
**
** The default behavior is to ignore closed leaves (closeMode==0).  To
** Show all leaves, use closeMode==1.  To show only closed leaves, use
** closeMode==2.
*/
void compute_leaves(int iBase, int closeMode){






  /* Create the LEAVES table if it does not already exist.  Make sure
  ** it is empty.
  */
  db_multi_exec(
    "CREATE TEMP TABLE IF NOT EXISTS leaves("
    "  rid INTEGER PRIMARY KEY"
    ");"
    "DELETE FROM leaves;"
  );

  /* We are checking all descendants of iBase.  If iBase==0, then
  ** use a short-cut to find all leaves anywhere in the hierarchy.
  */
  if( iBase<=0 ){
    db_multi_exec(
      "INSERT OR IGNORE INTO leaves"
      "  SELECT cid FROM plink"
      "  EXCEPT"
      "  SELECT pid FROM plink"
      "   WHERE coalesce((SELECT value FROM tagxref"
                         " WHERE tagid=%d AND rid=plink.pid),'trunk')"
           " == coalesce((SELECT value FROM tagxref"
                         " WHERE tagid=%d AND rid=plink.cid),'trunk');",
      TAG_BRANCH, TAG_BRANCH
    );

  }else{
    Bag seen;     /* Descendants seen */
    Bag pending;  /* Unpropagated descendants */
    Stmt q1;      /* Query to find children of a check-in */
    Stmt isBr;    /* Query to check to see if a check-in starts a new branch */
    Stmt ins;     /* INSERT statement for a new record */

    /* Initialize the bags. */
    bag_init(&seen);
    bag_init(&pending);
    bag_insert(&pending, iBase);

    /* This query returns all non-branch-merge children of check-in :rid.
    **
    ** If a a child is a merge of a fork within the same branch, it is 
    ** returned.  Only merge children in different branches are excluded.
    */
    db_prepare(&q1,
      "SELECT cid FROM plink"
      " WHERE pid=:rid"
      "   AND (isprim"
      "        OR coalesce((SELECT value FROM tagxref"
                        "   WHERE tagid=%d AND rid=plink.pid), 'trunk')"
                 "=coalesce((SELECT value FROM tagxref"
                        "   WHERE tagid=%d AND rid=plink.cid), 'trunk'))",
      TAG_BRANCH, TAG_BRANCH
    );
  
    /* This query returns a single row if check-in :rid is the first
    ** check-in of a new branch.
    */
    db_prepare(&isBr, 
       "SELECT 1 FROM tagxref"
       " WHERE rid=:rid AND tagid=%d AND tagtype=2"
       "   AND srcid>0",
       TAG_BRANCH
    );
  
    /* This statement inserts check-in :rid into the LEAVES table.
    */
    db_prepare(&ins, "INSERT OR IGNORE INTO leaves VALUES(:rid)");
  
    while( bag_count(&pending) ){
      int rid = bag_first(&pending);
      int cnt = 0;
      bag_remove(&pending, rid);
      db_bind_int(&q1, ":rid", rid);
      while( db_step(&q1)==SQLITE_ROW ){
        int cid = db_column_int(&q1, 0);
        if( bag_insert(&seen, cid) ){
          bag_insert(&pending, cid);
        }
        db_bind_int(&isBr, ":rid", cid);
        if( db_step(&isBr)==SQLITE_DONE ){
          cnt++;
        }
        db_reset(&isBr);
      }
      db_reset(&q1);
      if( cnt==0 && !is_a_leaf(rid) ){
        cnt++;
      }
      if( cnt==0 ){
        db_bind_int(&ins, ":rid", rid);
        db_step(&ins);
        db_reset(&ins);
      }
    }
    db_finalize(&ins);
    db_finalize(&isBr);
    db_finalize(&q1);
    bag_clear(&pending);
    bag_clear(&seen);
  }
  if( closeMode==1 ){
    db_multi_exec(
      "DELETE FROM leaves WHERE rid IN"
      "  (SELECT leaves.rid FROM leaves, tagxref"
      "    WHERE tagxref.rid=leaves.rid "
      "      AND tagxref.tagid=%d"
      "      AND tagxref.tagtype>0)",