1 files changed, 21 insertions, 13 deletions
diff --git a/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go
index 6bfc73a0c..ef83f0184 100644
--- a/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go
+++ b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go
@@ -9,20 +9,26 @@ import (
 	"golang.org/x/sys/windows"
 )
 
-func NewMemory(_, max uint64) experimental.LinearMemory {
+func NewMemory(cap, max uint64) experimental.LinearMemory {
 	// Round up to the page size.
 	rnd := uint64(windows.Getpagesize() - 1)
-	max = (max + rnd) &^ rnd
+	res := (max + rnd) &^ rnd
 
-	if max > math.MaxInt {
-		// This ensures uintptr(max) overflows to a large value,
+	if res > math.MaxInt {
+		// This ensures uintptr(res) overflows to a large value,
 		// and windows.VirtualAlloc returns an error.
-		max = math.MaxUint64
+		res = math.MaxUint64
 	}
 
-	// Reserve max bytes of address space, to ensure we won't need to move it.
-	// This does not commit memory.
-	r, err := windows.VirtualAlloc(0, uintptr(max), windows.MEM_RESERVE, windows.PAGE_READWRITE)
+	com := res
+	kind := windows.MEM_COMMIT
+	if cap < max { // Commit memory only if cap=max.
+		com = 0
+		kind = windows.MEM_RESERVE
+	}
+
+	// Reserve res bytes of address space, to ensure we won't need to move it.
+	r, err := windows.VirtualAlloc(0, uintptr(res), uint32(kind), windows.PAGE_READWRITE)
 	if err != nil {
 		panic(err)
 	}
@@ -30,8 +36,9 @@ func NewMemory(_, max uint64) experimental.LinearMemory {
 	mem := virtualMemory{addr: r}
 	// SliceHeader, although deprecated, avoids a go vet warning.
 	sh := (*reflect.SliceHeader)(unsafe.Pointer(&mem.buf))
-	sh.Cap = int(max)
 	sh.Data = r
+	sh.Len = int(com)
+	sh.Cap = int(res)
 	return &mem
 }
 
@@ -47,9 +54,11 @@ func (m *virtualMemory) Reallocate(size uint64) []byte {
 	com := uint64(len(m.buf))
 	res := uint64(cap(m.buf))
 	if com < size && size <= res {
-		// Round up to the page size.
+		// Grow geometrically, round up to the page size.
 		rnd := uint64(windows.Getpagesize() - 1)
-		new := (size + rnd) &^ rnd
+		new := com + com>>3
+		new = min(max(size, new), res)
+		new = (new + rnd) &^ rnd
 
 		// Commit additional memory up to new bytes.
 		_, err := windows.VirtualAlloc(m.addr, uintptr(new), windows.MEM_COMMIT, windows.PAGE_READWRITE)
@@ -57,8 +66,7 @@ func (m *virtualMemory) Reallocate(size uint64) []byte {
 			return nil
 		}
 
-		// Update committed memory.
-		m.buf = m.buf[:new]
+		m.buf = m.buf[:new] // Update committed memory.
 	}
 	// Limit returned capacity because bytes beyond
 	// len(m.buf) have not yet been committed.