bt_overflow.c File Reference

#include <sys/param.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../include/db.h"
#include "btree.h"

Include dependency graph for bt_overflow.c:

Go to the source code of this file.

Functions
int	__ovfl_delete (BTREE *t, void *p)
int	__ovfl_get (BTREE *t, void *p, size_t *ssz, void **buf, size_t *bufsz)
int	__ovfl_put (BTREE *t, const DBT *dbt, pgno_t *pg)

Function Documentation

__ovfl_delete()

int __ovfl_delete	(	BTREE *	t,
		void *	p
	)

Definition at line 193 of file bt_overflow.c.

References __bt_free(), _btree::bt_mp, _btree::bt_psize, BTDATAOFF, _page::flags, mpool_get(), mpool_put(), _page::nextpg, NULL, P_INVALID, P_PRESERVE, RET_ERROR, and RET_SUCCESS.

Referenced by __bt_dleaf(), __bt_pdelete(), and __rec_dleaf().

{
   PAGE *h;
   pgno_t pg;
   size_t plen;
   u_int32_t sz;

   memmove(&pg, p, sizeof(pgno_t));
   memmove(&sz, (char *)p + sizeof(pgno_t), sizeof(u_int32_t));

#ifdef DEBUG
   if (pg == P_INVALID || sz == 0)
      abort();
#endif
   if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
      return (RET_ERROR);

   /* Don't delete chains used by internal pages. */
   if (h->flags & P_PRESERVE) {
      mpool_put(t->bt_mp, h, 0);
      return (RET_SUCCESS);
   }

   /* Step through the chain, calling the free routine for each page. */
   for (plen = t->bt_psize - BTDATAOFF;; sz -= plen) {
      pg = h->nextpg;
      __bt_free(t, h);
      if (sz <= plen)
         break;
      if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
         return (RET_ERROR);
   }
   return (RET_SUCCESS);
}

__ovfl_get()

int __ovfl_get	(	BTREE *	t,
		void *	p,
		size_t *	ssz,
		void **	buf,
		size_t *	bufsz
	)

Definition at line 80 of file bt_overflow.c.

References _btree::bt_mp, _btree::bt_psize, BTDATAOFF, buf, malloc(), MIN, mpool_get(), mpool_put(), _page::nextpg, NULL, P_INVALID, realloc, RET_ERROR, and RET_SUCCESS.

Referenced by __bt_cmp(), __bt_ret(), and __rec_ret().

{
   PAGE *h;
   pgno_t pg;
   size_t nb, plen;
   u_int32_t sz;

   memmove(&pg, p, sizeof(pgno_t));
   memmove(&sz, (char *)p + sizeof(pgno_t), sizeof(u_int32_t));
   *ssz = sz;

#ifdef DEBUG
   if (pg == P_INVALID || sz == 0)
      abort();
#endif
   /* Make the buffer bigger as necessary. */
   if (*bufsz < sz) {
      *buf = (char *)(*buf == NULL ? malloc(sz) : realloc(*buf, sz));
      if (*buf == NULL)
         return (RET_ERROR);
      *bufsz = sz;
   }

   /*
    * Step through the linked list of pages, copying the data on each one
    * into the buffer.  Never copy more than the data's length.
    */
   plen = t->bt_psize - BTDATAOFF;
   for (p = *buf;; p = (char *)p + nb, pg = h->nextpg) {
      if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
         return (RET_ERROR);

      nb = MIN(sz, plen);
      memmove(p, (char *)h + BTDATAOFF, nb);
      mpool_put(t->bt_mp, h, 0);

      if ((sz -= nb) == 0)
         break;
   }
   return (RET_SUCCESS);
}

__ovfl_put()

int __ovfl_put	(	BTREE *	t,
		const DBT *	dbt,
		pgno_t *	pg
	)

Definition at line 139 of file bt_overflow.c.

References __bt_new(), _btree::bt_mp, _btree::bt_psize, BTDATAOFF, DBT::data, _page::flags, last, _page::lower, MIN, MPOOL_DIRTY, mpool_put(), _page::nextpg, NULL, P_INVALID, P_OVERFLOW, _page::pgno, _page::prevpg, RET_ERROR, RET_SUCCESS, DBT::size, and _page::upper.

Referenced by __bt_put(), and __rec_iput().

{
   PAGE *h, *last;
   void *p;
   pgno_t npg;
   size_t nb, plen;
   u_int32_t sz;

   /*
    * Allocate pages and copy the key/data record into them.  Store the
    * number of the first page in the chain.
    */
   plen = t->bt_psize - BTDATAOFF;
   for (last = NULL, p = dbt->data, sz = dbt->size;;
       p = (char *)p + plen, last = h) {
      if ((h = __bt_new(t, &npg)) == NULL)
         return (RET_ERROR);

      h->pgno = npg;
      h->nextpg = h->prevpg = P_INVALID;
      h->flags = P_OVERFLOW;
      h->lower = h->upper = 0;

      nb = MIN(sz, plen);
      memmove((char *)h + BTDATAOFF, p, nb);

      if (last) {
         last->nextpg = h->pgno;
         mpool_put(t->bt_mp, last, MPOOL_DIRTY);
      } else
         *pg = h->pgno;

      if ((sz -= nb) == 0) {
         mpool_put(t->bt_mp, h, MPOOL_DIRTY);
         break;
      }
   }
   return (RET_SUCCESS);
}