From c9a7cbbdb385521f992d60539daa6a94d403d253 Mon Sep 17 00:00:00 2001
From: Austin Horstman <khaneliman12@gmail.com>
Date: Mon, 9 Feb 2026 15:26:23 -0600
Subject: [PATCH] fix(image): treat missing interval as once

PR #4390 enabled millisecond intervals but changed image interval parsing so a missing interval could resolve to 1ms. That creates a hot update loop and can spike CPU and destabilize rendering in drawer/group setups (issue #4835).

Use explicit semantics: missing, null, non-numeric, or <=0 interval is treated as "once" (max sleep), while positive numeric values still support ms precision with a 1ms floor. This keeps the intended feature (sub-second polling when requested) without defaulting to busy looping.

Also align waybar-image(5) docs with runtime behavior.

Signed-off-by: Austin Horstman <khaneliman12@gmail.com>
---
 man/waybar-image.5.scd |  3 ++-
 src/modules/image.cpp  | 27 ++++++++++++++++-----------
 2 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/man/waybar-image.5.scd b/man/waybar-image.5.scd
index 8c991265..8be182a6 100644
--- a/man/waybar-image.5.scd
+++ b/man/waybar-image.5.scd
@@ -26,7 +26,8 @@ The *image* module displays an image from a path.
 *interval*: ++
 	typeof: integer or float ++
 	The interval (in seconds) to re-render the image. ++
-	Minimum value is 0.001 (1ms). Values smaller than 1ms will be set to 1ms. ++
+	If set to a positive value, the minimum is 0.001 (1ms). Values smaller than 1ms will be set to 1ms. ++
+	Zero or negative values are treated as "once". ++
 	This is useful if the contents of *path* changes. ++
 	If no *interval* is defined, the image will only be rendered once.
 
diff --git a/src/modules/image.cpp b/src/modules/image.cpp
index 189deee6..98bf3c46 100644
--- a/src/modules/image.cpp
+++ b/src/modules/image.cpp
@@ -14,22 +14,27 @@ waybar::modules::Image::Image(const std::string& id, const Json::Value& config)
 
   size_ = config["size"].asInt();
 
-  interval_ = config_["interval"] == "once"
-                  ? std::chrono::milliseconds::max()
-                  : std::chrono::milliseconds(std::max(
-                        1L,  // Minimum 1ms due to millisecond precision
-                        static_cast<long>(
-                            (config_["interval"].isNumeric() ? config_["interval"].asDouble() : 0) *
-                            1000)));
+  const auto once = std::chrono::milliseconds::max();
+  if (!config_.isMember("interval") || config_["interval"].isNull() ||
+      config_["interval"] == "once") {
+    interval_ = once;
+  } else if (config_["interval"].isNumeric()) {
+    const auto interval_seconds = config_["interval"].asDouble();
+    if (interval_seconds <= 0) {
+      interval_ = once;
+    } else {
+      interval_ =
+          std::chrono::milliseconds(std::max(1L,  // Minimum 1ms due to millisecond precision
+                                             static_cast<long>(interval_seconds * 1000)));
+    }
+  } else {
+    interval_ = once;
+  }
 
   if (size_ == 0) {
     size_ = 16;
   }
 
-  if (interval_.count() == 0) {
-    interval_ = std::chrono::milliseconds::max();
-  }
-
   delayWorker();
 }