TODO

1 files changed, 14 insertions, 108 deletions

diff --git a/page.go b/page.go
index 736aa91..ba39dc5 100644
--- a/page.go
+++ b/page.go
@@ -8,55 +8,26 @@ import (
 const maxPageSize = 0x8000
 const minKeyCount = 2
 
-var _page page
-
-const pageHeaderSize = int(unsafe.Offsetof(_page.ptr))
+const pageHeaderSize = int(unsafe.Offsetof(((*page)(nil)).data))
 
 const minPageKeys = 2
 const fillThreshold = 250 // 25%
 
 const (
-	p_branch   = 0x01
-	p_leaf     = 0x02
-	p_overflow = 0x04
-	p_meta     = 0x08
-	p_dirty    = 0x10 /**< dirty page, also set for #P_SUBP pages */
-
-	p_invalid = ^pgno(0)
-)
-
-// maxCommitPages is the maximum number of pages to commit in one writev() call.
-const maxCommitPages = 64
-
-/* max bytes to write in one call */
-const maxWriteByteCount uint = 0x80000000 // TODO: #define MAX_WRITE 0x80000000U >> (sizeof(ssize_t) == 4))
-
-// TODO:
-// #if defined(IOV_MAX) && IOV_MAX < MDB_COMMIT_PAGES
-// #undef MDB_COMMIT_PAGES
-// #define MDB_COMMIT_PAGES	IOV_MAX
-// #endif
-
-const (
-	MDB_PS_MODIFY   = 1
-	MDB_PS_ROOTONLY = 2
-	MDB_PS_FIRST    = 4
-	MDB_PS_LAST     = 8
+	p_branch = 0x01
+	p_leaf   = 0x02
+	p_meta   = 0x04
 )
 
-// TODO: #define MDB_SPLIT_REPLACE	MDB_APPENDDUP	/**< newkey is not new */
-
-type pgno uint64
-type txnid uint64
-type indx uint16
+type pgid uint64
 
 type page struct {
-	id       pgno
-	flags    uint16
-	lower    indx
-	upper    indx
-	overflow uint32
-	ptr      uintptr
+	id    pgid
+	flags uint32
+	lower uint16
+	upper uint16
+	count uint32
+	data  uintptr
 }
 
 // meta returns a pointer to the metadata section of the page.
@@ -80,72 +51,7 @@ func (p *page) init(pageSize int) {
 	m := (*meta)(unsafe.Pointer(&p.ptr))
 	m.magic = magic
 	m.version = version
-	m.free.pad = uint32(pageSize)
-	m.pgno = 1
-	m.free.root = p_invalid
-	m.buckets.root = p_invalid
-}
-
-// branchNode retrieves the branch node at the given index within the page.
-func (p *page) branchNode(index indx) *branchNode {
-	b := (*[maxPageSize]byte)(unsafe.Pointer(&p.ptr))
-	return (*branchNode)(unsafe.Pointer(&b[index*indx(unsafe.Sizeof(index))]))
-}
-
-// leafNode retrieves the leaf node at the given index within the page.
-func (p *page) leafNode(index indx) *leafNode {
-	b := (*[maxPageSize]byte)(unsafe.Pointer(&p.ptr))
-	return (*leafNode)(unsafe.Pointer(&b[index*indx(unsafe.Sizeof(index))]))
-}
-
-// numkeys returns the number of nodes in the page.
-func (p *page) numkeys() int {
-	return int((p.lower - indx(pageHeaderSize)) >> 1)
-}
-
-// remainingSize returns the number of bytes left in the page.
-func (p *page) remainingSize() int {
-	return int(p.upper - p.lower)
-}
-
-// find returns the node with the smallest entry larger or equal to the key.
-// This function also returns a boolean stating if an exact match was made.
-func (p *page) find(key []byte, pageSize int) (*node, int, bool) {
-	// TODO: MDB_page *mp = mc->mc_pg[mc->mc_top];
-
-	var node *node
-	nkeys := p.numkeys()
-	low, high := 1, nkeys-1
-	if (p.flags & p_leaf) != 0 {
-		low = 0
-	}
-
-	// Perform a binary search to find the correct node.
-	var i, rc int
-	for low <= high {
-		i = (low + high) / 2
-
-		node = p.node(indx(i))
-		rc = bytes.Compare(key, node.key())
-		if rc == 0 {
-			break
-		} else if rc > 0 {
-			low = i + 1
-		} else {
-			high = i - 1
-		}
-	}
-
-	// Found entry is less than key so grab the next one.
-	if rc > 0 {
-		i++
-	}
-
-	// If index is beyond key range then return nil.
-	if i >= nkeys {
-		node = nil
-	}
-
-	exact := (rc == 0 && nkeys > 0)
-	return node, i, exact
+	m.pageSize = uint32(pageSize)
+	m.pgid = 1
+	m.buckets.root = 0
 }