freetype:harfbuzz: fix type for shapers args

Non zero-terminated slices of the previous type caused runtime errors.

libs/freetype/src/harfbuzz/common.zig

@@ -276,6 +276,8 @@ pub const Tag = struct {
     }
 };
 
+pub const Shapers = ?[*:null]const ?[*:0]const u8;
+
 pub extern fn hb_feature_from_string(str: [*c]const u8, len: c_int, feature: [*c]Feature) u8;
 pub extern fn hb_feature_to_string(feature: [*c]Feature, buf: [*c]u8, size: c_uint) void;
 pub extern fn hb_variation_from_string(str: [*c]const u8, len: c_int, variation: [*c]Variation) u8;

libs/freetype/src/harfbuzz/font.zig

@@ -5,6 +5,7 @@ const Face = @import("face.zig").Face;
 const Buffer = @import("buffer.zig").Buffer;
 const Feature = @import("common.zig").Feature;
 const SegmentProps = @import("buffer.zig").SegmentProps;
+const Shapers = @import("common.zig").Shapers;
 
 pub const Font = struct {
     handle: *c.hb_font_t,
@@ -86,13 +87,13 @@ pub const Font = struct {
         );
     }
 
-    pub fn shapeFull(self: Font, buf: Buffer, features: ?[]const Feature, shapers: []const []const u8) error{ShapingFailed}!void {
+    pub fn shapeFull(self: Font, buf: Buffer, features: ?[]const Feature, shapers: Shapers) error{ShapingFailed}!void {
         if (hb_shape_full(
             self.handle,
             buf.handle,
             if (features) |f| f.ptr else null,
             if (features) |f| @intCast(c_uint, f.len) else 0,
-            @ptrCast([*c]const [*c]const u8, shapers),
+            shapers,
         ) < 1) return error.ShapingFailed;
     }
 };

libs/freetype/src/harfbuzz/shape.zig

@@ -3,7 +3,7 @@ const c = @import("c.zig");
 
 pub const ListShapers = struct {
     index: usize,
-    list: [*c][*c]const u8,
+    list: [*:null]const ?[*:0]const u8,
 
     pub fn init() ListShapers {
         return .{ .index = 0, .list = c.hb_shape_list_shapers() };
@@ -11,9 +11,8 @@ pub const ListShapers = struct {
 
     pub fn next(self: *ListShapers) ?[:0]const u8 {
         self.index += 1;
-        return std.mem.span(@ptrCast(
+        return std.mem.span(
-            ?[*:0]const u8,
             self.list[self.index - 1] orelse return null,
-        ));
+        );
     }
 };

libs/freetype/src/harfbuzz/shape_plan.zig

@@ -5,31 +5,32 @@ const Font = @import("font.zig").Font;
 const Face = @import("face.zig").Face;
 const SegmentProps = @import("buffer.zig").SegmentProps;
 const Feature = @import("common.zig").Feature;
+const Shapers = @import("common.zig").Shapers;
 
 pub const ShapePlan = struct {
     handle: *c.hb_shape_plan_t,
 
-    pub fn init(face: Face, props: SegmentProps, features: ?[]const Feature, shapers: []const []const u8) ShapePlan {
+    pub fn init(face: Face, props: SegmentProps, features: ?[]const Feature, shapers: Shapers) ShapePlan {
         return .{ .handle = hb_shape_plan_create(
             face.handle,
             &props.cast(),
             if (features) |f| f.ptr else null,
             if (features) |f| @intCast(c_uint, f.len) else 0,
-            @ptrCast([*c]const [*c]const u8, shapers),
+            shapers,
         ).? };
     }
 
-    pub fn initCached(face: Face, props: SegmentProps, features: ?[]const Feature, shapers: []const []const u8) ShapePlan {
+    pub fn initCached(face: Face, props: SegmentProps, features: ?[]const Feature, shapers: Shapers) ShapePlan {
         return .{ .handle = hb_shape_plan_create_cached(
             face.handle,
             &props.cast(),
             if (features) |f| f.ptr else null,
             if (features) |f| @intCast(c_uint, f.len) else 0,
-            @ptrCast([*c]const [*c]const u8, shapers),
+            shapers,
         ).? };
     }
 
-    pub fn init2(face: Face, props: SegmentProps, features: ?[]const Feature, cords: []const i32, shapers: []const []const u8) ShapePlan {
+    pub fn init2(face: Face, props: SegmentProps, features: ?[]const Feature, cords: []const i32, shapers: Shapers) ShapePlan {
         return .{ .handle = hb_shape_plan_create2(
             face.handle,
             &props.cast(),
@@ -37,11 +38,11 @@ pub const ShapePlan = struct {
             if (features) |f| @intCast(c_uint, f.len) else 0,
             cords.ptr,
             @intCast(c_uint, cords.len),
-            @ptrCast([*c]const [*c]const u8, shapers),
+            shapers,
         ).? };
     }
 
-    pub fn initCached2(face: Face, props: SegmentProps, features: ?[]const Feature, cords: []const i32, shapers: []const []const u8) ShapePlan {
+    pub fn initCached2(face: Face, props: SegmentProps, features: ?[]const Feature, cords: []const i32, shapers: Shapers) ShapePlan {
         return .{ .handle = hb_shape_plan_create_cached2(
             face.handle,
             &props.cast(),
@@ -49,7 +50,7 @@ pub const ShapePlan = struct {
             if (features) |f| @intCast(c_uint, f.len) else 0,
             cords.ptr,
             @intCast(c_uint, cords.len),
-            @ptrCast([*c]const [*c]const u8, shapers),
+            shapers,
         ).? };
     }