From 4a6c0ab086eec189350f0424ffea5387b9a35638 Mon Sep 17 00:00:00 2001
From: Todd Gruben <todd@molecula.com>
Date: Wed, 9 Mar 2022 21:02:39 -0600
Subject: [PATCH 1/4] bitmapN not reliable et

---
 rbf/cursorx.go | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/rbf/cursorx.go b/rbf/cursorx.go
index 0a29f07f3..fafdbf512 100644
--- a/rbf/cursorx.go
+++ b/rbf/cursorx.go
@@ -177,7 +177,7 @@ func intoContainer(l leafCell, tx *Tx, replacing *roaring.Container, target []by
 	case ContainerTypeBitmapPtr:
 		_, bm, _ := tx.leafCellBitmap(toPgno(cpMaybe))
 		cloneMaybe := bm
-		c = roaring.RemakeContainerBitmapN(replacing, cloneMaybe, int32(l.BitN))
+		c = roaring.RemakeContainerBitmap(replacing, cloneMaybe)
 	case ContainerTypeBitmap:
 		c = roaring.RemakeContainerBitmapN(replacing, toArray64(cpMaybe), int32(l.BitN))
 	case ContainerTypeRLE:
@@ -216,9 +216,9 @@ func toContainer(l leafCell, tx *Tx) (c *roaring.Container) {
 	case ContainerTypeBitmapPtr:
 		_, bm, _ := tx.leafCellBitmap(toPgno(cpMaybe))
 		cloneMaybe := bm
-		c = roaring.NewContainerBitmap(l.BitN, cloneMaybe)
+		c = roaring.NewContainerBitmap(-1, cloneMaybe)
 	case ContainerTypeBitmap:
-		c = roaring.NewContainerBitmap(l.BitN, toArray64(cpMaybe))
+		c = roaring.NewContainerBitmap(-1, toArray64(cpMaybe))
 	case ContainerTypeRLE:
 		c = roaring.NewContainerRun(toInterval16(cpMaybe))
 	}

From 09a993295157d14efaecb73ca88a9a532c05fce4 Mon Sep 17 00:00:00 2001
From: Todd Gruben <todd@molecula.com>
Date: Thu, 10 Mar 2022 07:48:51 -0600
Subject: [PATCH 2/4] extra protection of bitmapToArray

---
 roaring/containers_test.go |  8 ++++++++
 roaring/roaring.go         | 41 ++++++++++++++++++++++++++++----------
 2 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/roaring/containers_test.go b/roaring/containers_test.go
index e5d9fc2c4..5e170d4d1 100644
--- a/roaring/containers_test.go
+++ b/roaring/containers_test.go
@@ -176,6 +176,14 @@ func TestSliceContainers(t *testing.T) {
 	})
 }
 
+func TestContainersFB1247(t *testing.T) {
+	bm := [bitmapN]uint64{0xF}
+	co := NewContainerBitmap(1, bm[:])
+	co = co.bitmapToArray()
+	//should not panic
+
+}
+
 func genRun(r *rand.Rand) Interval16 {
 gen:
 	dat := r.Uint32()
diff --git a/roaring/roaring.go b/roaring/roaring.go
index 9f2ef5039..afbaa6b42 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -3567,21 +3567,40 @@ func (c *Container) bitmapToArray() *Container {
 		return c
 	}
 	bitmap := c.bitmap()
-	n := int32(0)
 
-	array := make([]uint16, c.N())
-	for i, word := range bitmap {
-		for word != 0 {
-			t := word & -word
-			if roaringParanoia {
-				if n >= c.N() {
-					panic("bitmap has more bits set than container.n")
+	// FB-1247 adding an extra check just in case c.N proves to be unreliable
+	// TODO  prove this has to be reliable
+	makeArray := func(bm []uint64, ar []uint16) ([]uint16, bool, int32) {
+		n := int32(0)
+		for i, word := range bm {
+			for word != 0 {
+				t := word & -word
+				if roaringParanoia {
+					if n >= c.N() {
+						panic("bitmap has more bits set than container.n")
+					}
 				}
+				if n == int32(len(ar)) {
+					return ar, true, n
+				}
+				ar[n] = uint16((i*64 + int(popcount(t-1))))
+				n++
+				word ^= t
 			}
-			array[n] = uint16((i*64 + int(popcount(t-1))))
-			n++
-			word ^= t
 		}
+		return ar, false, n
+	}
+	array, fail, n := makeArray(bitmap, make([]uint16, c.N()))
+	if fail {
+		// the onlyreason we are here is because N was incorrect
+		// so we force a recount of N and try again
+		c.bitmapRepair() // the onlyreason we are here is because N was incorrect
+		array, fail, n = makeArray(bitmap, make([]uint16, c.N()))
+		if fail {
+			//this should not be able to happen under any circumstance
+			panic("bitmapToArray failure")
+		}
+
 	}
 	if roaringParanoia {
 		if n != c.N() {

From 52e9027c791ddbba393a585e11f9fcc100b0abc9 Mon Sep 17 00:00:00 2001
From: tgruben <tgruben@gmail.com>
Date: Thu, 10 Mar 2022 08:26:07 -0600
Subject: [PATCH 3/4] Update roaring.go

---
 roaring/roaring.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/roaring/roaring.go b/roaring/roaring.go
index afbaa6b42..c09ae4673 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -3594,7 +3594,7 @@ func (c *Container) bitmapToArray() *Container {
 	if fail {
 		// the onlyreason we are here is because N was incorrect
 		// so we force a recount of N and try again
-		c.bitmapRepair() // the onlyreason we are here is because N was incorrect
+		c.bitmapRepair() 
 		array, fail, n = makeArray(bitmap, make([]uint16, c.N()))
 		if fail {
 			//this should not be able to happen under any circumstance

From 57b8dcd43a4f0d2f1b31402bee578b91291c3f01 Mon Sep 17 00:00:00 2001
From: Todd Gruben <todd@molecula.com>
Date: Thu, 10 Mar 2022 09:03:07 -0600
Subject: [PATCH 4/4] go fmt

---
 roaring/roaring.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/roaring/roaring.go b/roaring/roaring.go
index c09ae4673..ffc0c3c3c 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -3594,7 +3594,7 @@ func (c *Container) bitmapToArray() *Container {
 	if fail {
 		// the onlyreason we are here is because N was incorrect
 		// so we force a recount of N and try again
-		c.bitmapRepair() 
+		c.bitmapRepair()
 		array, fail, n = makeArray(bitmap, make([]uint16, c.N()))
 		if fail {
 			//this should not be able to happen under any circumstance