From 762a2074eeada1aa0c61a3f1bed662ff05e5119b Mon Sep 17 00:00:00 2001
From: Erik Arvstedt <erik.arvstedt@gmail.com>
Date: Wed, 5 Apr 2023 16:37:51 +0200
Subject: [PATCH] freetype: fix type for C string args

Propagate the correct string type required by Freetype to the Zig layer.
Previously, passing non zero-terminated strings caused runtime errors.
---
 libs/freetype/src/Face.zig     | 2 +-
 libs/freetype/src/Library.zig  | 2 +-
 libs/freetype/src/freetype.zig | 6 ++++--
 libs/freetype/src/main.zig     | 2 +-
 4 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/libs/freetype/src/Face.zig b/libs/freetype/src/Face.zig
index 8f3041c9..ad805da5 100644
--- a/libs/freetype/src/Face.zig
+++ b/libs/freetype/src/Face.zig
@@ -58,7 +58,7 @@ pub fn deinit(self: Face) void {
     _ = c.FT_Done_Face(self.handle);
 }
 
-pub fn attachFile(self: Face, path: []const u8) Error!void {
+pub fn attachFile(self: Face, path: [*:0]const u8) Error!void {
     return self.attachStream(.{
         .flags = .{ .path = true },
         .data = .{ .path = path },
diff --git a/libs/freetype/src/Library.zig b/libs/freetype/src/Library.zig
index 8fa1bbd2..9ab79b06 100644
--- a/libs/freetype/src/Library.zig
+++ b/libs/freetype/src/Library.zig
@@ -30,7 +30,7 @@ pub fn deinit(self: Library) void {
     _ = c.FT_Done_FreeType(self.handle);
 }
 
-pub fn createFace(self: Library, path: []const u8, face_index: i32) Error!Face {
+pub fn createFace(self: Library, path: [*:0]const u8, face_index: i32) Error!Face {
     return self.openFace(.{
         .flags = .{ .path = true },
         .data = .{ .path = path },
diff --git a/libs/freetype/src/freetype.zig b/libs/freetype/src/freetype.zig
index 0d99e693..b96c0277 100644
--- a/libs/freetype/src/freetype.zig
+++ b/libs/freetype/src/freetype.zig
@@ -159,7 +159,7 @@ pub const OpenArgs = struct {
     flags: OpenFlags,
     data: union(enum) {
         memory: []const u8,
-        path: []const u8,
+        path: [*:0]const u8,
         stream: c.FT_Stream,
         driver: c.FT_Module,
         params: []const c.FT_Parameter,
@@ -173,7 +173,9 @@ pub const OpenArgs = struct {
                 oa.memory_base = d.ptr;
                 oa.memory_size = @intCast(u31, d.len);
             },
-            .path => |*d| oa.pathname = @intToPtr(*u8, @ptrToInt(d.ptr)),
+            // The Freetype API requires a mutable string.
+            // This is an oversight, Freetype actually never writes to this string.
+            .path => |d| oa.pathname = @constCast(d),
             .stream => |d| oa.stream = d,
             .driver => |d| oa.driver = d,
             .params => |*d| {
diff --git a/libs/freetype/src/main.zig b/libs/freetype/src/main.zig
index ac242633..3d558307 100644
--- a/libs/freetype/src/main.zig
+++ b/libs/freetype/src/main.zig
@@ -13,7 +13,7 @@ const std = @import("std");
 const testing = std.testing;
 const ft = @import("freetype.zig");
 
-fn sdkPath(comptime suffix: []const u8) []const u8 {
+fn sdkPath(comptime suffix: [*:0]const u8) [*:0]const u8 {
     if (suffix[0] != '/') @compileError("suffix must be an absolute path");
     return comptime blk: {
         const root_dir = std.fs.path.dirname(@src().file) orelse ".";