From 173e27d2e81c9f4a299d1acdc881b832041b241c Mon Sep 17 00:00:00 2001
From: Wez Furlong <wez@wezfurlong.org>
Date: Mon, 14 Nov 2022 13:26:02 -0700
Subject: [PATCH] Add support for heap profiling using dhat

refs: https://github.com/wez/wezterm/issues/2626
---
 .gitignore              |  1 +
 Cargo.lock              | 43 +++++++++++++++++++++++++++++++++++++++++
 wezterm-gui/Cargo.toml  |  3 +++
 wezterm-gui/src/main.rs |  7 +++++++
 4 files changed, 54 insertions(+)

diff --git a/.gitignore b/.gitignore
index 377635872..59509c753 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 .DS_Store
+dhat-heap.json
 /docs/_site
 /PKGBUILD
 /WezTerm*.zip
diff --git a/Cargo.lock b/Cargo.lock
index b24f6ce1e..174fa6823 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1081,6 +1081,22 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "dhat"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4f2aaf837aaf456f6706cb46386ba8dffd4013a757e36f4ea05c20dd46b209a3"
+dependencies = [
+ "backtrace",
+ "lazy_static",
+ "mintex",
+ "parking_lot 0.12.1",
+ "rustc-hash",
+ "serde",
+ "serde_json",
+ "thousands",
+]
+
 [[package]]
 name = "diff"
 version = "0.1.13"
@@ -2639,6 +2655,16 @@ dependencies = [
  "adler",
 ]
 
+[[package]]
+name = "mintex"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fd7c5ba1c3b5a23418d7bbf98c71c3d4946a0125002129231da8d6b723d559cb"
+dependencies = [
+ "once_cell",
+ "sys-info",
+]
+
 [[package]]
 name = "mio"
 version = "0.8.5"
@@ -4583,6 +4609,16 @@ dependencies = [
  "yaml-rust",
 ]
 
+[[package]]
+name = "sys-info"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b3a0d0aba8bf96a0e1ddfdc352fc53b3df7f39318c71854910c3c4b024ae52c"
+dependencies = [
+ "cc",
+ "libc",
+]
+
 [[package]]
 name = "tabout"
 version = "0.3.0"
@@ -4778,6 +4814,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "thousands"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3bf63baf9f5039dadc247375c29eb13706706cfde997d0330d05aa63a77d8820"
+
 [[package]]
 name = "thread_local"
 version = "1.1.4"
@@ -5576,6 +5618,7 @@ dependencies = [
  "codec",
  "colorgrad",
  "config",
+ "dhat",
  "dirs-next",
  "downcast-rs",
  "embed-resource",
diff --git a/wezterm-gui/Cargo.toml b/wezterm-gui/Cargo.toml
index 5d0ceda4b..0b9f6314f 100644
--- a/wezterm-gui/Cargo.toml
+++ b/wezterm-gui/Cargo.toml
@@ -22,6 +22,8 @@ vendored-fonts = [
   "vendor-roboto-font",
   "vendor-noto-emoji-font"
 ]
+dhat-heap = ["dhat"]    # if you are doing heap profiling
+dhat-ad-hoc = ["dhat"]  # if you are doing ad hoc profiling
 
 [build-dependencies]
 anyhow = "1.0"
@@ -39,6 +41,7 @@ codec = { path = "../codec" }
 colorgrad = "0.6"
 config = { path = "../config" }
 downcast-rs = "1.0"
+dhat = {version="0.3", optional=true}
 dirs-next = "2.0"
 emojis = "0.5"
 env-bootstrap = { path = "../env-bootstrap" }
diff --git a/wezterm-gui/src/main.rs b/wezterm-gui/src/main.rs
index d00ed8e74..eebb8cf5c 100644
--- a/wezterm-gui/src/main.rs
+++ b/wezterm-gui/src/main.rs
@@ -51,6 +51,10 @@ mod uniforms;
 mod update;
 mod utilsprites;
 
+#[cfg(feature = "dhat-heap")]
+#[global_allocator]
+static ALLOC: dhat::Alloc = dhat::Alloc;
+
 pub use selection::SelectionMode;
 pub use termwindow::{set_window_class, set_window_position, TermWindow, ICON_DATA};
 
@@ -755,6 +759,9 @@ fn terminate_with_error(err: anyhow::Error) -> ! {
 }
 
 fn main() {
+    #[cfg(feature = "dhat-heap")]
+    let _profiler = dhat::Profiler::new_heap();
+
     config::designate_this_as_the_main_thread();
     config::assign_error_callback(mux::connui::show_configuration_error_message);
     notify_on_panic();