Function WriteInodeToPage

internal/common/inode.go:70–105

(inodes Inodes, p *Page)

}

func WriteInodeToPage(inodes Inodes, p *Page) uint32 {
	// Loop over each item and write it to the page.
	// off tracks the offset into p of the start of the next data.
	off := unsafe.Sizeof(*p) + p.PageElementSize()*uintptr(len(inodes))
	isLeaf := p.IsLeafPage()
	for i, item := range inodes {
		Assert(len(item.Key()) > 0, "write: zero-length inode key")

		// Create a slice to write into of needed size and advance
		// byte pointer for next iteration.
		sz := len(item.Key()) + len(item.Value())
		b := UnsafeByteSlice(unsafe.Pointer(p), off, 0, sz)
		off += uintptr(sz)

		// Write the page element.
		if isLeaf {
			elem := p.LeafPageElement(uint16(i))
			elem.SetPos(uint32(uintptr(unsafe.Pointer(&b[0])) - uintptr(unsafe.Pointer(elem))))
			elem.SetFlags(item.Flags())
			elem.SetKsize(uint32(len(item.Key())))
			elem.SetVsize(uint32(len(item.Value())))
		} else {
			elem := p.BranchPageElement(uint16(i))
			elem.SetPos(uint32(uintptr(unsafe.Pointer(&b[0])) - uintptr(unsafe.Pointer(elem))))
			elem.SetKsize(uint32(len(item.Key())))
			elem.SetPgid(item.Pgid())
			Assert(elem.Pgid() != p.Id(), "write: circular dependency occurred")
		}

		// Write data for the element to the end of the page.
		l := copy(b, item.Key())
		copy(b[l:], item.Value())
	}

	return uint32(off)
}

func UsedSpaceInPage(inodes Inodes, p *Page) uint32 {
	off := unsafe.Sizeof(*p) + p.PageElementSize()*uintptr(len(inodes))