From 6317022304a49c0033c52f0c6cdfe038e88dd314 Mon Sep 17 00:00:00 2001
From: Austin Horstman <khaneliman12@gmail.com>
Date: Fri, 6 Mar 2026 18:33:19 -0600
Subject: [PATCH] fix(hyprland): guard malformed module events

The language and submap modules assumed their Hyprland payload delimiters were
always present. When that assumption is violated, the old code could perform
invalid iterator math or throw while slicing the event string.

Validate the expected separators up front and bail out with a warning when the
event is malformed so the modules degrade safely instead of crashing the update
path.

Signed-off-by: Austin Horstman <khaneliman12@gmail.com>
---
 src/modules/hyprland/language.cpp | 26 +++++++++++++++++++++-----
 src/modules/hyprland/submap.cpp   |  7 ++++++-
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/src/modules/hyprland/language.cpp b/src/modules/hyprland/language.cpp
index 25f6789d..6e0fe23d 100644
--- a/src/modules/hyprland/language.cpp
+++ b/src/modules/hyprland/language.cpp
@@ -63,19 +63,35 @@ auto Language::update() -> void {
 
 void Language::onEvent(const std::string& ev) {
   std::lock_guard<std::mutex> lg(mutex_);
-  std::string kbName(begin(ev) + ev.find_last_of('>') + 1, begin(ev) + ev.find_first_of(','));
+  const auto payloadStart = ev.find(">>");
+  if (payloadStart == std::string::npos) {
+    spdlog::warn("hyprland language received malformed event: {}", ev);
+    return;
+  }
+  const auto payload = ev.substr(payloadStart + 2);
+  const auto kbSeparator = payload.find(',');
+  if (kbSeparator == std::string::npos) {
+    spdlog::warn("hyprland language received malformed event payload: {}", ev);
+    return;
+  }
+  std::string kbName = payload.substr(0, kbSeparator);
 
   // Last comma before variants parenthesis, eg:
   // activelayout>>micro-star-int'l-co.,-ltd.-msi-gk50-elite-gaming-keyboard,English (US, intl.,
   // with dead keys)
   std::string beforeParenthesis;
-  auto parenthesisPos = ev.find_last_of('(');
+  auto parenthesisPos = payload.find_last_of('(');
   if (parenthesisPos == std::string::npos) {
-    beforeParenthesis = ev;
+    beforeParenthesis = payload;
   } else {
-    beforeParenthesis = std::string(begin(ev), begin(ev) + parenthesisPos);
+    beforeParenthesis = payload.substr(0, parenthesisPos);
   }
-  auto layoutName = ev.substr(beforeParenthesis.find_last_of(',') + 1);
+  const auto layoutSeparator = beforeParenthesis.find_last_of(',');
+  if (layoutSeparator == std::string::npos) {
+    spdlog::warn("hyprland language received malformed layout payload: {}", ev);
+    return;
+  }
+  auto layoutName = payload.substr(layoutSeparator + 1);
 
   if (config_.isMember("keyboard-name") && kbName != config_["keyboard-name"].asString())
     return;  // ignore
diff --git a/src/modules/hyprland/submap.cpp b/src/modules/hyprland/submap.cpp
index ff18e7f3..36b9bf79 100644
--- a/src/modules/hyprland/submap.cpp
+++ b/src/modules/hyprland/submap.cpp
@@ -75,7 +75,12 @@ void Submap::onEvent(const std::string& ev) {
     return;
   }
 
-  auto submapName = ev.substr(ev.find_first_of('>') + 2);
+  const auto separator = ev.find(">>");
+  if (separator == std::string::npos) {
+    spdlog::warn("hyprland submap received malformed event: {}", ev);
+    return;
+  }
+  auto submapName = ev.substr(separator + 2);
 
   submap_ = submapName;