diff options
| -rw-r--r-- | dbm/src/h_bigkey.c | 120 | ||||
| -rw-r--r-- | dbm/src/hash_buf.c | 6 |
2 files changed, 84 insertions, 42 deletions
diff --git a/dbm/src/h_bigkey.c b/dbm/src/h_bigkey.c index 53a1a00f3..855f10725 100644 --- a/dbm/src/h_bigkey.c +++ b/dbm/src/h_bigkey.c @@ -364,6 +364,7 @@ __big_return( BUFHEAD *save_p; uint16 *bp, len, off, save_addr; char *tp; + int save_flags; bp = (uint16 *)bufp->page; while (bp[ndx + 1] == PARTIAL_KEY) { @@ -428,7 +429,12 @@ __big_return( return (0); } + /* pin our saved buf so that we don't lose if + * we run out of buffers */ + save_flags = save_p->flags; + save_p->flags |= BUF_PIN; val->size = collect_data(hashp, bufp, (int)len, set_current); + save_p->flags = save_flags; if (val->size == (size_t)-1) return (-1); if (save_p->addr != save_addr) { @@ -440,9 +446,14 @@ __big_return( val->data = (uint8 *)hashp->tmp_buf; return (0); } + + /* - * Count how big the total datasize is by recursing through the pages. Then - * allocate a buffer and copy the data as you recurse up. + * Count how big the total datasize is by looping through the pages. Then + * allocate a buffer and copy the data in the second loop. NOTE: Our caller + * may already have a bp which it is holding onto. The caller is + * responsible for copying that bp into our temp buffer. 'len' is how much + * space to reserve for that buffer. */ static int collect_data( @@ -451,56 +462,81 @@ collect_data( int len, int set) { register uint16 *bp; - register char *p; - BUFHEAD *xbp; - uint16 save_addr; + BUFHEAD *save_bufp; + int save_flags; int mylen, totlen; - p = bufp->page; - bp = (uint16 *)p; - mylen = hashp->BSIZE - bp[1]; - - /* if mylen ever goes negative it means that the - * page is screwed up. + /* + * save the input buf head because we need to walk the list twice. + * pin it to make sure it doesn't leave the buffer pool. + * This has the effect of growing the buffer pool if necessary. */ - if(mylen < 0) - return (-1); + save_bufp = bufp; + save_flags = save_bufp->flags; + save_bufp->flags |= BUF_PIN; - save_addr = bufp->addr; + /* read the length of the buffer */ + for (totlen = len; bufp ; bufp = __get_buf(hashp, bp[bp[0]-1], bufp, 0)) { + bp = (uint16 *)bufp->page; + mylen = hashp->BSIZE - bp[1]; - if (bp[2] == FULL_KEY_DATA) { /* End of Data */ - totlen = len + mylen; - if (hashp->tmp_buf) - free(hashp->tmp_buf); - if ((hashp->tmp_buf = (char *)malloc((size_t)totlen)) == NULL) + /* if mylen ever goes negative it means that the + * page is screwed up. + */ + if (mylen < 0) { + save_bufp->flags = save_flags; return (-1); - if (set) { - hashp->cndx = 1; - if (bp[0] == 2) { /* No more buckets in chain */ - hashp->cpage = NULL; - hashp->cbucket++; - } else { - hashp->cpage = - __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!hashp->cpage) - return (-1); - else if (!((uint16 *)hashp->cpage->page)[0]) { - hashp->cbucket++; - hashp->cpage = NULL; - } - } + } + totlen += mylen; + if (bp[2] == FULL_KEY_DATA) { /* End of Data */ + break; } - } else { - xbp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!xbp || ((totlen = - collect_data(hashp, xbp, len + mylen, set)) < 1)) - return (-1); } - if (bufp->addr != save_addr) { - errno = EINVAL; /* Out of buffers. */ + + if (!bufp) { + save_bufp->flags = save_flags; return (-1); } - memmove(&hashp->tmp_buf[len], (bufp->page) + bp[1], (size_t)mylen); + + /* allocate a temp buf */ + if (hashp->tmp_buf) + free(hashp->tmp_buf); + if ((hashp->tmp_buf = (char *)malloc((size_t)totlen)) == NULL) { + save_bufp->flags = save_flags; + return (-1); + } + + /* copy the buffers back into temp buf */ + for (bufp = save_bufp; bufp ; + bufp = __get_buf(hashp, bp[bp[0]-1], bufp, 0)) { + bp = (uint16 *)bufp->page; + mylen = hashp->BSIZE - bp[1]; + memmove(&hashp->tmp_buf[len], (bufp->page) + bp[1], (size_t)mylen); + len += mylen; + if (bp[2] == FULL_KEY_DATA) { + break; + } + } + + /* 'clear' the pin flags */ + save_bufp->flags = save_flags; + + /* update the database cursor */ + if (set) { + hashp->cndx = 1; + if (bp[0] == 2) { /* No more buckets in chain */ + hashp->cpage = NULL; + hashp->cbucket++; + } else { + hashp->cpage = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); + if (!hashp->cpage) + return (-1); + else if (!((uint16 *)hashp->cpage->page)[0]) { + hashp->cbucket++; + hashp->cpage = NULL; + } + } + } return (totlen); } diff --git a/dbm/src/hash_buf.c b/dbm/src/hash_buf.c index 7bfe01a34..d1193de6f 100644 --- a/dbm/src/hash_buf.c +++ b/dbm/src/hash_buf.c @@ -284,6 +284,12 @@ newbuf(HTAB *hashp, uint32 addr, BUFHEAD *prev_bp) xbp->ovfl = 0; xbp = next_xbp; + /* leave pinned pages alone, we are still using + * them. */ + if (xbp->flags & BUF_PIN) { + continue; + } + /* Check that ovfl pointer is up date. */ if (IS_BUCKET(xbp->flags) || (oaddr != xbp->addr)) |