From e7d571c8daf3ca97645434fef48563c3eae2edbd Mon Sep 17 00:00:00 2001
From: Stephen Miller <56742918+StevenMiller123@users.noreply.github.com>
Date: Thu, 30 Apr 2026 15:00:21 -0500
Subject: [PATCH] Common: Restore old log filter behavior (#4336)

* Restore old log filter behavior

Not sure exactly why this hadn't happened yet.

* Suggested change

* Update documentation to include changes

* Remove mention of debug log class

Debug is both a valid class and level, kinda confusing to use it as an example in my opinion.

* Error instead of assert

* Missing include
---
 documents/Debugging/Debugging.md | 10 +++++-----
 src/common/logging/log.cpp       | 14 ++++++++++----
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/documents/Debugging/Debugging.md b/documents/Debugging/Debugging.md
index 82a93e670..0ccef6bf0 100644
--- a/documents/Debugging/Debugging.md
+++ b/documents/Debugging/Debugging.md
@@ -64,13 +64,13 @@ You can configure the emulator by editing the `config.toml` file found in the `u
     - It can be beneficial to set this to `false` for better performance.
     - When communicating about issues with games and the log messages aren't clear due to potentially confusing order, set this to `true` and send that log instead.
   - `filter`: Sets the logging category for various logging classes.
-    - Format: `<class>=<level>,...`
-    - Multiple classes can be set by separating them with a comma. (example: `Render=warning,Debug=critical,Lib.Pad=error`)
+    - Format: `<class>:<level> ...`
+    - Multiple classes can be set by separating them with a space. (example: `Render:Warning Lib.Pad:Error`)
     - Sub-classes can be specified in the same format as seen in the console/log (such as `Core.Linker`).  
-    - Valid log levels: `trace, debug, info, warning, error, critical` - in this order, setting a level silences all levels preceding it and logs every level after it.
+    - Valid log levels: `trace, debug, info, warning, error, critical, off` - in this order, setting a level silences all levels preceding it and logs every level after it.
     - Examples:
-      - If the log is being spammed with messages coming from Lib.Pad, you can use `Lib.Pad=critical` to only log critical-level messages.
-      - If you'd like to mute everything, but still want to receive messages from Vulkan rendering: `off,Render.Vulkan=info` (if you want critical at least `critical,Render.Vulkan=info`)
+      - If the log is being spammed with messages coming from Lib.Pad, you can use `Lib.Pad:Critical` to only log critical-level messages.
+      - If you'd like to mute everything, but still want to receive messages from Vulkan rendering: `*:Off Render.Vulkan:Info` (if you want critical at least `*:Critical Render.Vulkan:Info`)
   - `skipDuplicate`: Skip same lines with a `Skipped N duplicate messages..` message (`true`/`false`)
     - By default, the emulator will skip same lines for `maxSkipDuration` milliseconds.
   - `append`: Append log to the existing file (`true`/`false`)
diff --git a/src/common/logging/log.cpp b/src/common/logging/log.cpp
index 511eda668..c8bfbdb4d 100644
--- a/src/common/logging/log.cpp
+++ b/src/common/logging/log.cpp
@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <cstdlib>
+#include <iostream>
 #include <string>
 
 #include "common/assert.h"
@@ -200,12 +201,17 @@ void Setup(std::string_view log_filename) {
     std::unordered_map<std::string, spdlog::level> log_level_per_class;
 
     if (EmulatorSettings.IsLogEnable()) {
-        for (const auto class_level : std::views::split(EmulatorSettings.GetLogFilter(), ',')) {
+        for (const auto class_level : std::views::split(EmulatorSettings.GetLogFilter(), ' ')) {
             const auto class_level_pair =
-                std::views::split(class_level, '=') | std::ranges::to<std::vector<std::string>>();
+                std::views::split(class_level, ':') | std::ranges::to<std::vector<std::string>>();
 
-            if (class_level_pair.size() == 1) {
-                default_log_level = spdlog::level_from_str(class_level_pair.front() |
+            if (class_level_pair.size() != 2) {
+                std::cerr << "bad log filter provided" << std::endl;
+                continue;
+            }
+
+            if (class_level_pair.front()[0] == '*') {
+                default_log_level = spdlog::level_from_str(class_level_pair.back() |
                                                            std::ranges::to<std::string>());
             } else {
                 log_level_per_class[class_level_pair.front() | std::ranges::to<std::string>()] =