From 3dc2757330230a521a4693eb5d7bbea6ef292e2a Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Thu, 5 Mar 2020 13:09:28 +0000
Subject: [PATCH 1/3] add more "const" decls

---
 libvips/arithmetic/boolean.c      | 17 ++++++-----
 libvips/arithmetic/linear.c       |  5 ++--
 libvips/arithmetic/math2.c        |  8 ++---
 libvips/arithmetic/relational.c   | 17 ++++++-----
 libvips/arithmetic/remainder.c    |  5 ++--
 libvips/include/vips/arithmetic.h | 49 +++++++++++++++++++------------
 6 files changed, 60 insertions(+), 41 deletions(-)

diff --git a/libvips/arithmetic/boolean.c b/libvips/arithmetic/boolean.c
index c4fcf18d..ad978fe1 100644
--- a/libvips/arithmetic/boolean.c
+++ b/libvips/arithmetic/boolean.c
@@ -562,7 +562,7 @@ vips_boolean_const_init( VipsBooleanConst *boolean_const )
 
 static int
 vips_boolean_constv( VipsImage *in, VipsImage **out, 
-	VipsOperationBoolean operation, double *c, int n, va_list ap )
+	VipsOperationBoolean operation, const double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -609,7 +609,7 @@ vips_boolean_constv( VipsImage *in, VipsImage **out,
  */
 int
 vips_boolean_const( VipsImage *in, VipsImage **out, 
-	VipsOperationBoolean boolean, double *c, int n, ... )
+	VipsOperationBoolean boolean, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -637,7 +637,8 @@ vips_boolean_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_andimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_andimage_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -666,7 +667,8 @@ vips_andimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_orimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_orimage_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -695,7 +697,8 @@ vips_orimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_eorimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_eorimage_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -724,7 +727,7 @@ vips_eorimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_lshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_lshift_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -753,7 +756,7 @@ vips_lshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_rshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_rshift_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/linear.c b/libvips/arithmetic/linear.c
index 4a376a55..ebf4fb33 100644
--- a/libvips/arithmetic/linear.c
+++ b/libvips/arithmetic/linear.c
@@ -453,7 +453,7 @@ vips_linear_init( VipsLinear *linear )
 
 static int
 vips_linearv( VipsImage *in, VipsImage **out, 
-	double *a, double *b, int n, va_list ap )
+	const double *a, const double *b, int n, va_list ap )
 {
 	VipsArea *area_a;
 	VipsArea *area_b;
@@ -500,7 +500,8 @@ vips_linearv( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_linear( VipsImage *in, VipsImage **out, double *a, double *b, int n, ... )
+vips_linear( VipsImage *in, VipsImage **out, 
+	const double *a, const double *b, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/math2.c b/libvips/arithmetic/math2.c
index cbcd2b99..dd3e5323 100644
--- a/libvips/arithmetic/math2.c
+++ b/libvips/arithmetic/math2.c
@@ -420,7 +420,7 @@ vips_math2_const_init( VipsMath2Const *math2_const )
 
 static int
 vips_math2_constv( VipsImage *in, VipsImage **out, 
-	VipsOperationMath2 math2, double *c, int n, va_list ap )
+	VipsOperationMath2 math2, const double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -470,7 +470,7 @@ vips_math2_constv( VipsImage *in, VipsImage **out,
  */
 int
 vips_math2_const( VipsImage *in, VipsImage **out, 
-	VipsOperationMath2 math2, double *c, int n, ... )
+	VipsOperationMath2 math2, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -496,7 +496,7 @@ vips_math2_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_pow_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_pow_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -523,7 +523,7 @@ vips_pow_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_wop_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_wop_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/relational.c b/libvips/arithmetic/relational.c
index f2f8f817..d740ea5c 100644
--- a/libvips/arithmetic/relational.c
+++ b/libvips/arithmetic/relational.c
@@ -598,7 +598,7 @@ vips_relational_const_init( VipsRelationalConst *relational_const )
 
 static int
 vips_relational_constv( VipsImage *in, VipsImage **out, 
-	VipsOperationRelational relational, double *c, int n, va_list ap )
+	VipsOperationRelational relational, const double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -645,7 +645,7 @@ vips_relational_constv( VipsImage *in, VipsImage **out,
  */
 int
 vips_relational_const( VipsImage *in, VipsImage **out, 
-	VipsOperationRelational relational, double *c, int n, ... )
+	VipsOperationRelational relational, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -671,7 +671,7 @@ vips_relational_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_equal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_equal_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -698,7 +698,8 @@ vips_equal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_notequal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_notequal_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -725,7 +726,7 @@ vips_notequal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_less_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_less_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -752,7 +753,7 @@ vips_less_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_lesseq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_lesseq_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -779,7 +780,7 @@ vips_lesseq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_more_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_more_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -806,7 +807,7 @@ vips_more_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_moreeq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_moreeq_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/remainder.c b/libvips/arithmetic/remainder.c
index 75df8f4d..3c994345 100644
--- a/libvips/arithmetic/remainder.c
+++ b/libvips/arithmetic/remainder.c
@@ -333,7 +333,7 @@ vips_remainder_const_init( VipsRemainderConst *remainder_const )
 
 static int
 vips_remainder_constv( VipsImage *in, VipsImage **out, 
-	double *c, int n, va_list ap )
+	const double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -379,7 +379,8 @@ vips_remainder_constv( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_remainder_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+vips_remainder_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/include/vips/arithmetic.h b/libvips/include/vips/arithmetic.h
index ce95399a..3c9c7aa9 100644
--- a/libvips/include/vips/arithmetic.h
+++ b/libvips/include/vips/arithmetic.h
@@ -185,14 +185,14 @@ int vips_multiply( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 int vips_divide( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_linear( VipsImage *in, VipsImage **out, 
-	double *a, double *b, int n, ... )
+	const double *a, const double *b, int n, ... )
 	__attribute__((sentinel));
 int vips_linear1( VipsImage *in, VipsImage **out, double a, double b, ... )
 	__attribute__((sentinel));
 int vips_remainder( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_remainder_const( VipsImage *in, VipsImage **out, 
-	double *c, int n, ... )
+	const double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_remainder_const1( VipsImage *in, VipsImage **out, 
 	double c, ... )
@@ -279,19 +279,25 @@ int vips_more( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 int vips_moreeq( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_relational_const( VipsImage *in, VipsImage **out, 
-	VipsOperationRelational relational, double *c, int n, ... )
+	VipsOperationRelational relational, const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_equal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_equal_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_notequal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_notequal_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_less_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_less_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_lesseq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_lesseq_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_more_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_more_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_moreeq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_moreeq_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_relational_const1( VipsImage *in, VipsImage **out, 
 	VipsOperationRelational relational, double c, ... )
@@ -324,17 +330,22 @@ int vips_rshift( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 
 int vips_boolean_const( VipsImage *in, VipsImage **out, 
-	VipsOperationBoolean boolean, double *c, int n, ... )
+	VipsOperationBoolean boolean, const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_andimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_andimage_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_orimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_orimage_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_eorimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_eorimage_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_lshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_lshift_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_rshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_rshift_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_boolean_const1( VipsImage *in, VipsImage **out, 
 	VipsOperationBoolean boolean, double c, ... )
@@ -358,11 +369,13 @@ int vips_pow( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 int vips_wop( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_math2_const( VipsImage *in, VipsImage **out, 
-	VipsOperationMath2 math2, double *c, int n, ... )
+	VipsOperationMath2 math2, const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_pow_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_pow_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_wop_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
+int vips_wop_const( VipsImage *in, VipsImage **out, 
+	const double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_math2_const1( VipsImage *in, VipsImage **out, 
 	VipsOperationMath2 math2, double c, ... )

From 6a2fbbaed7345a144c84e4b07c3ced040fde7efd Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Thu, 5 Mar 2020 13:40:07 +0000
Subject: [PATCH 2/3] Revert "add more "const" decls"

This reverts commit 3dc2757330230a521a4693eb5d7bbea6ef292e2a.
---
 libvips/arithmetic/boolean.c      | 17 +++++------
 libvips/arithmetic/linear.c       |  5 ++--
 libvips/arithmetic/math2.c        |  8 ++---
 libvips/arithmetic/relational.c   | 17 +++++------
 libvips/arithmetic/remainder.c    |  5 ++--
 libvips/include/vips/arithmetic.h | 49 ++++++++++++-------------------
 6 files changed, 41 insertions(+), 60 deletions(-)

diff --git a/libvips/arithmetic/boolean.c b/libvips/arithmetic/boolean.c
index ad978fe1..c4fcf18d 100644
--- a/libvips/arithmetic/boolean.c
+++ b/libvips/arithmetic/boolean.c
@@ -562,7 +562,7 @@ vips_boolean_const_init( VipsBooleanConst *boolean_const )
 
 static int
 vips_boolean_constv( VipsImage *in, VipsImage **out, 
-	VipsOperationBoolean operation, const double *c, int n, va_list ap )
+	VipsOperationBoolean operation, double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -609,7 +609,7 @@ vips_boolean_constv( VipsImage *in, VipsImage **out,
  */
 int
 vips_boolean_const( VipsImage *in, VipsImage **out, 
-	VipsOperationBoolean boolean, const double *c, int n, ... )
+	VipsOperationBoolean boolean, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -637,8 +637,7 @@ vips_boolean_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_andimage_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+vips_andimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -667,8 +666,7 @@ vips_andimage_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_orimage_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+vips_orimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -697,8 +695,7 @@ vips_orimage_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_eorimage_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+vips_eorimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -727,7 +724,7 @@ vips_eorimage_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_lshift_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_lshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -756,7 +753,7 @@ vips_lshift_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_rshift_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_rshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/linear.c b/libvips/arithmetic/linear.c
index ebf4fb33..4a376a55 100644
--- a/libvips/arithmetic/linear.c
+++ b/libvips/arithmetic/linear.c
@@ -453,7 +453,7 @@ vips_linear_init( VipsLinear *linear )
 
 static int
 vips_linearv( VipsImage *in, VipsImage **out, 
-	const double *a, const double *b, int n, va_list ap )
+	double *a, double *b, int n, va_list ap )
 {
 	VipsArea *area_a;
 	VipsArea *area_b;
@@ -500,8 +500,7 @@ vips_linearv( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_linear( VipsImage *in, VipsImage **out, 
-	const double *a, const double *b, int n, ... )
+vips_linear( VipsImage *in, VipsImage **out, double *a, double *b, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/math2.c b/libvips/arithmetic/math2.c
index dd3e5323..cbcd2b99 100644
--- a/libvips/arithmetic/math2.c
+++ b/libvips/arithmetic/math2.c
@@ -420,7 +420,7 @@ vips_math2_const_init( VipsMath2Const *math2_const )
 
 static int
 vips_math2_constv( VipsImage *in, VipsImage **out, 
-	VipsOperationMath2 math2, const double *c, int n, va_list ap )
+	VipsOperationMath2 math2, double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -470,7 +470,7 @@ vips_math2_constv( VipsImage *in, VipsImage **out,
  */
 int
 vips_math2_const( VipsImage *in, VipsImage **out, 
-	VipsOperationMath2 math2, const double *c, int n, ... )
+	VipsOperationMath2 math2, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -496,7 +496,7 @@ vips_math2_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_pow_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_pow_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -523,7 +523,7 @@ vips_pow_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_wop_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_wop_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/relational.c b/libvips/arithmetic/relational.c
index d740ea5c..f2f8f817 100644
--- a/libvips/arithmetic/relational.c
+++ b/libvips/arithmetic/relational.c
@@ -598,7 +598,7 @@ vips_relational_const_init( VipsRelationalConst *relational_const )
 
 static int
 vips_relational_constv( VipsImage *in, VipsImage **out, 
-	VipsOperationRelational relational, const double *c, int n, va_list ap )
+	VipsOperationRelational relational, double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -645,7 +645,7 @@ vips_relational_constv( VipsImage *in, VipsImage **out,
  */
 int
 vips_relational_const( VipsImage *in, VipsImage **out, 
-	VipsOperationRelational relational, const double *c, int n, ... )
+	VipsOperationRelational relational, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -671,7 +671,7 @@ vips_relational_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_equal_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_equal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -698,8 +698,7 @@ vips_equal_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_notequal_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+vips_notequal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -726,7 +725,7 @@ vips_notequal_const( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_less_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_less_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -753,7 +752,7 @@ vips_less_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_lesseq_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_lesseq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -780,7 +779,7 @@ vips_lesseq_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_more_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_more_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
@@ -807,7 +806,7 @@ vips_more_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_moreeq_const( VipsImage *in, VipsImage **out, const double *c, int n, ... )
+vips_moreeq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/arithmetic/remainder.c b/libvips/arithmetic/remainder.c
index 3c994345..75df8f4d 100644
--- a/libvips/arithmetic/remainder.c
+++ b/libvips/arithmetic/remainder.c
@@ -333,7 +333,7 @@ vips_remainder_const_init( VipsRemainderConst *remainder_const )
 
 static int
 vips_remainder_constv( VipsImage *in, VipsImage **out, 
-	const double *c, int n, va_list ap )
+	double *c, int n, va_list ap )
 {
 	VipsArea *area_c;
 	double *array; 
@@ -379,8 +379,7 @@ vips_remainder_constv( VipsImage *in, VipsImage **out,
  * Returns: 0 on success, -1 on error
  */
 int
-vips_remainder_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+vips_remainder_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 {
 	va_list ap;
 	int result;
diff --git a/libvips/include/vips/arithmetic.h b/libvips/include/vips/arithmetic.h
index 3c9c7aa9..ce95399a 100644
--- a/libvips/include/vips/arithmetic.h
+++ b/libvips/include/vips/arithmetic.h
@@ -185,14 +185,14 @@ int vips_multiply( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 int vips_divide( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_linear( VipsImage *in, VipsImage **out, 
-	const double *a, const double *b, int n, ... )
+	double *a, double *b, int n, ... )
 	__attribute__((sentinel));
 int vips_linear1( VipsImage *in, VipsImage **out, double a, double b, ... )
 	__attribute__((sentinel));
 int vips_remainder( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_remainder_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+	double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_remainder_const1( VipsImage *in, VipsImage **out, 
 	double c, ... )
@@ -279,25 +279,19 @@ int vips_more( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 int vips_moreeq( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_relational_const( VipsImage *in, VipsImage **out, 
-	VipsOperationRelational relational, const double *c, int n, ... )
+	VipsOperationRelational relational, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_equal_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_equal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_notequal_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_notequal_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_less_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_less_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_lesseq_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_lesseq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_more_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_more_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_moreeq_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_moreeq_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_relational_const1( VipsImage *in, VipsImage **out, 
 	VipsOperationRelational relational, double c, ... )
@@ -330,22 +324,17 @@ int vips_rshift( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 
 int vips_boolean_const( VipsImage *in, VipsImage **out, 
-	VipsOperationBoolean boolean, const double *c, int n, ... )
+	VipsOperationBoolean boolean, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_andimage_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_andimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_orimage_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_orimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_eorimage_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_eorimage_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_lshift_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_lshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_rshift_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_rshift_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_boolean_const1( VipsImage *in, VipsImage **out, 
 	VipsOperationBoolean boolean, double c, ... )
@@ -369,13 +358,11 @@ int vips_pow( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 int vips_wop( VipsImage *left, VipsImage *right, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_math2_const( VipsImage *in, VipsImage **out, 
-	VipsOperationMath2 math2, const double *c, int n, ... )
+	VipsOperationMath2 math2, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_pow_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_pow_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
-int vips_wop_const( VipsImage *in, VipsImage **out, 
-	const double *c, int n, ... )
+int vips_wop_const( VipsImage *in, VipsImage **out, double *c, int n, ... )
 	__attribute__((sentinel));
 int vips_math2_const1( VipsImage *in, VipsImage **out, 
 	VipsOperationMath2 math2, double c, ... )

From b3a7929247fbac033771685fe5102cbda632f8c2 Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Thu, 5 Mar 2020 15:02:16 +0000
Subject: [PATCH 3/3] detect read errors in sniff correctly

we has a signed/unsigned mixup :(
---
 ChangeLog                | 1 +
 libvips/iofuncs/source.c | 6 +++---
 libvips/iofuncs/util.c   | 4 ++++
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 9575253c..08cfbe09 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,7 @@
 - better gifload behaviour for DISPOSAL_UNSPECIFIED [DarthSim]
 - ban ppm max_value < 0 
 - add fuzz corpus to dist
+- detect read errors correctly in source_sniff
 
 20/6/19 started 8.9.1
 - don't use the new source loaders for new_from_file or new_from_buffer, it
diff --git a/libvips/iofuncs/source.c b/libvips/iofuncs/source.c
index 3c286007..994caa9e 100644
--- a/libvips/iofuncs/source.c
+++ b/libvips/iofuncs/source.c
@@ -1153,7 +1153,7 @@ vips_source_length( VipsSource *source )
 }
 
 /**
- * vips_source_peek: 
+ * vips_source_sniff_at_most: 
  * @source: peek this source
  * @data: return a pointer to the bytes read here
  * @length: max number of bytes to read
@@ -1219,13 +1219,13 @@ unsigned char *
 vips_source_sniff( VipsSource *source, size_t length )
 {
 	unsigned char *data;
-	size_t bytes_read;
+	gint64 bytes_read;
 
 	if( vips_source_test_features( source ) )
 		return( NULL );
 
 	bytes_read = vips_source_sniff_at_most( source, &data, length );
-	if( bytes_read < length )
+	if( bytes_read < (gint64) length )
 		return( NULL );
 
 	return( data );
diff --git a/libvips/iofuncs/util.c b/libvips/iofuncs/util.c
index 48001ed6..09ef6757 100644
--- a/libvips/iofuncs/util.c
+++ b/libvips/iofuncs/util.c
@@ -1036,6 +1036,10 @@ vips__seek_no_error( int fd, gint64 pos, int whence )
 #ifdef OS_WIN32
 	new_pos = _lseeki64( fd, pos, whence );
 #else /*!OS_WIN32*/
+	/* On error, eg. opening a directory and seeking to the end, lseek() 
+	 * on linux seems to return 9223372036854775807 ((1 << 63) - 1)
+	 * rather than (off_t) -1 for reasons I don't understand. 
+	 */
 	new_pos = lseek( fd, pos, whence );
 #endif /*OS_WIN32*/