From 8f477b00da8a503ef597099119e6957f663587d9 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <m@mitchellh.com>
Date: Sun, 1 Sep 2024 10:59:19 -0700
Subject: [PATCH] renderer/termio attach thread local state for crash capture

---
 src/crash/sentry.zig    | 15 +++++----------
 src/renderer/Thread.zig |  7 +++++++
 src/termio/Thread.zig   |  7 +++++++
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/src/crash/sentry.zig b/src/crash/sentry.zig
index 6b649e713..f1ab7b700 100644
--- a/src/crash/sentry.zig
+++ b/src/crash/sentry.zig
@@ -29,7 +29,7 @@ pub const ThreadState = struct {
 
 /// See ThreadState. This should only ever be set by the owner of the
 /// thread entry function.
-threadlocal var thread_state: ?ThreadState = null;
+pub threadlocal var thread_state: ?ThreadState = null;
 
 /// Process-wide initialization of our Sentry client.
 ///
@@ -140,15 +140,10 @@ fn beforeSend(
     // handler to set thread-specific data such as window size, grid size,
     // etc. that we can use to debug crashes.
 
-    const thr_state = thread_state orelse {
-        // If we don't have thread state we note this in the context
-        // so we can see that but don't do anything else.
-        const obj = sentry.Value.initObject();
-        errdefer obj.decref();
-        obj.setByKey("unknown", sentry.Value.initBool(true));
-        sentry.setContext("surface", obj);
-        return event_val;
-    };
+    // If we don't have thread state we can't reliably determine
+    // metadata such as surface dimensions. In the future we can probably
+    // drop full app state (all surfaces, all windows, etc.).
+    const thr_state = thread_state orelse return event_val;
 
     // Read the surface data. This is likely unsafe because on a crash
     // other threads can continue running. We don't have race-safe way to
diff --git a/src/renderer/Thread.zig b/src/renderer/Thread.zig
index 2521d18a4..1b730693b 100644
--- a/src/renderer/Thread.zig
+++ b/src/renderer/Thread.zig
@@ -5,6 +5,7 @@ pub const Thread = @This();
 const std = @import("std");
 const builtin = @import("builtin");
 const xev = @import("xev");
+const crash = @import("../crash/main.zig");
 const renderer = @import("../renderer.zig");
 const apprt = @import("../apprt.zig");
 const configpkg = @import("../config.zig");
@@ -191,6 +192,12 @@ pub fn threadMain(self: *Thread) void {
 fn threadMain_(self: *Thread) !void {
     defer log.debug("renderer thread exited", .{});
 
+    // Setup our crash metadata
+    crash.sentry.thread_state = .{
+        .surface = self.renderer.surface_mailbox.surface,
+    };
+    defer crash.sentry.thread_state = null;
+
     // Run our loop start/end callbacks if the renderer cares.
     const has_loop = @hasDecl(renderer.Renderer, "loopEnter");
     if (has_loop) try self.renderer.loopEnter(self);
diff --git a/src/termio/Thread.zig b/src/termio/Thread.zig
index 94650aef6..d38c6a1ce 100644
--- a/src/termio/Thread.zig
+++ b/src/termio/Thread.zig
@@ -15,6 +15,7 @@ const std = @import("std");
 const ArenaAllocator = std.heap.ArenaAllocator;
 const builtin = @import("builtin");
 const xev = @import("xev");
+const crash = @import("../crash/main.zig");
 const termio = @import("../termio.zig");
 const BlockingQueue = @import("../blocking_queue.zig").BlockingQueue;
 
@@ -200,6 +201,12 @@ pub fn threadMain(self: *Thread, io: *termio.Termio) void {
 fn threadMain_(self: *Thread, io: *termio.Termio) !void {
     defer log.debug("IO thread exited", .{});
 
+    // Setup our crash metadata
+    crash.sentry.thread_state = .{
+        .surface = io.surface_mailbox.surface,
+    };
+    defer crash.sentry.thread_state = null;
+
     // Get the mailbox. This must be an SPSC mailbox for threading.
     const mailbox = switch (io.mailbox) {
         .spsc => |*v| v,