From 8208947290b33d292fa60128d49b050ae3c51b43 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Wed, 27 Sep 2023 14:27:56 -0700
Subject: [PATCH] termio/exec: hook up xtgettcap

---
 src/terminal/dcs.zig | 18 ++++++++----------
 src/termio/Exec.zig  |  9 +++++++--
 2 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/terminal/dcs.zig b/src/terminal/dcs.zig
index b6a78afe9..83d4c7d22 100644
--- a/src/terminal/dcs.zig
+++ b/src/terminal/dcs.zig
@@ -123,13 +123,11 @@ pub const Command = union(enum) {
 
     pub const XTGETTCAP = struct {
         data: std.ArrayList(u8),
-
-        // Note: do not reset this. The next function mutates data so it is
-        // unsafe to reset this and reiterate.
         i: usize = 0,
 
         /// Returns the next terminfo key being requested and null
-        /// when there are no more keys.
+        /// when there are no more keys. The returned value is NOT hex-decoded
+        /// because we expect to use a comptime lookup table.
         pub fn next(self: *XTGETTCAP) ?[]const u8 {
             if (self.i >= self.data.items.len) return null;
 
@@ -141,9 +139,7 @@ pub const Command = union(enum) {
             // never read.
             self.i += idx + 1;
 
-            // HEX decode in-place so we don't have to allocate. If invalid
-            // hex is given then we just return null and stop processing.
-            return std.fmt.hexToBytes(rem, rem[0..idx]) catch null;
+            return rem[0..idx];
         }
     };
 };
@@ -183,7 +179,7 @@ test "XTGETTCAP command" {
     var cmd = h.unhook().?;
     defer cmd.deinit();
     try testing.expect(cmd == .xtgettcap);
-    try testing.expectEqualStrings("Smulx", cmd.xtgettcap.next().?);
+    try testing.expectEqualStrings("536D756C78", cmd.xtgettcap.next().?);
     try testing.expect(cmd.xtgettcap.next() == null);
 }
 
@@ -198,8 +194,8 @@ test "XTGETTCAP command multiple keys" {
     var cmd = h.unhook().?;
     defer cmd.deinit();
     try testing.expect(cmd == .xtgettcap);
-    try testing.expectEqualStrings("Smulx", cmd.xtgettcap.next().?);
-    try testing.expectEqualStrings("Smulx", cmd.xtgettcap.next().?);
+    try testing.expectEqualStrings("536D756C78", cmd.xtgettcap.next().?);
+    try testing.expectEqualStrings("536D756C78", cmd.xtgettcap.next().?);
     try testing.expect(cmd.xtgettcap.next() == null);
 }
 
@@ -214,5 +210,7 @@ test "XTGETTCAP command invalid data" {
     var cmd = h.unhook().?;
     defer cmd.deinit();
     try testing.expect(cmd == .xtgettcap);
+    try testing.expectEqualStrings("who", cmd.xtgettcap.next().?);
+    try testing.expectEqualStrings("536D756C78", cmd.xtgettcap.next().?);
     try testing.expect(cmd.xtgettcap.next() == null);
 }
diff --git a/src/termio/Exec.zig b/src/termio/Exec.zig
index 5ece318fb..d41d2f05c 100644
--- a/src/termio/Exec.zig
+++ b/src/termio/Exec.zig
@@ -13,6 +13,7 @@ const Command = @import("../Command.zig");
 const Pty = @import("../Pty.zig");
 const SegmentedPool = @import("../segmented_pool.zig").SegmentedPool;
 const terminal = @import("../terminal/main.zig");
+const terminfo = @import("../terminfo/main.zig");
 const xev = @import("xev");
 const renderer = @import("../renderer.zig");
 const tracy = @import("tracy");
@@ -1219,8 +1220,12 @@ const StreamHandler = struct {
 
         // log.warn("DCS command: {}", .{cmd});
         switch (cmd) {
-            .xtgettcap => |gettcap| {
-                _ = gettcap;
+            .xtgettcap => |*gettcap| {
+                const map = comptime terminfo.ghostty.xtgettcapMap();
+                while (gettcap.next()) |key| {
+                    const response = map.get(key) orelse continue;
+                    self.messageWriter(.{ .write_stable = response });
+                }
             },
         }
     }