Add configurable per-class log filtering

1 files changed, 132 insertions, 0 deletions

diff --git a/src/common/logging/filter.cpp b/src/common/logging/filter.cpp
new file mode 100644
index 00000000..0cf9b05e
--- /dev/null
+++ b/src/common/logging/filter.cpp
@@ -0,0 +1,132 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include <algorithm>
+
+#include "common/logging/filter.h"
+#include "common/logging/backend.h"
+#include "common/string_util.h"
+
+namespace Log {
+
+Filter::Filter(Level default_level) {
+    ResetAll(default_level);
+}
+
+void Filter::ResetAll(Level level) {
+    class_levels.fill(level);
+}
+
+void Filter::SetClassLevel(Class log_class, Level level) {
+    class_levels[static_cast<size_t>(log_class)] = level;
+}
+
+void Filter::SetSubclassesLevel(const ClassInfo& log_class, Level level) {
+    const size_t log_class_i = static_cast<size_t>(log_class.log_class);
+
+    const size_t begin = log_class_i + 1;
+    const size_t end = begin + log_class.num_children;
+    for (size_t i = begin; begin < end; ++i) {
+        class_levels[i] = level;
+    }
+}
+
+void Filter::ParseFilterString(const std::string& filter_str) {
+    auto clause_begin = filter_str.cbegin();
+    while (clause_begin != filter_str.cend()) {
+        auto clause_end = std::find(clause_begin, filter_str.cend(), ' ');
+
+        // If clause isn't empty
+        if (clause_end != clause_begin) {
+            ParseFilterRule(clause_begin, clause_end);
+        }
+
+        if (clause_end != filter_str.cend()) {
+            // Skip over the whitespace
+            ++clause_end;
+        }
+        clause_begin = clause_end;
+    }
+}
+
+template <typename It>
+static Level GetLevelByName(const It begin, const It end) {
+    for (u8 i = 0; i < static_cast<u8>(Level::Count); ++i) {
+        const char* level_name = Logger::GetLevelName(static_cast<Level>(i));
+        if (Common::ComparePartialString(begin, end, level_name)) {
+            return static_cast<Level>(i);
+        }
+    }
+    return Level::Count;
+}
+
+template <typename It>
+static Class GetClassByName(const It begin, const It end) {
+    for (ClassType i = 0; i < static_cast<ClassType>(Class::Count); ++i) {
+        const char* level_name = Logger::GetLogClassName(static_cast<Class>(i));
+        if (Common::ComparePartialString(begin, end, level_name)) {
+            return static_cast<Class>(i);
+        }
+    }
+    return Class::Count;
+}
+
+template <typename InputIt, typename T>
+static InputIt find_last(InputIt begin, const InputIt end, const T& value) {
+    auto match = end;
+    while (begin != end) {
+        auto new_match = std::find(begin, end, value);
+        if (new_match != end) {
+            match = new_match;
+            ++new_match;
+        }
+        begin = new_match;
+    }
+    return match;
+}
+
+bool Filter::ParseFilterRule(const std::string::const_iterator begin,
+        const std::string::const_iterator end) {
+    auto level_separator = std::find(begin, end, ':');
+    if (level_separator == end) {
+        LOG_ERROR(Log, "Invalid log filter. Must specify a log level after `:`: %s",
+                std::string(begin, end).c_str());
+        return false;
+    }
+
+    const Level level = GetLevelByName(level_separator + 1, end);
+    if (level == Level::Count) {
+        LOG_ERROR(Log, "Unknown log level in filter: %s", std::string(begin, end).c_str());
+        return false;
+    }
+
+    if (Common::ComparePartialString(begin, level_separator, "*")) {
+        ResetAll(level);
+        return true;
+    }
+
+    auto class_name_end = find_last(begin, level_separator, '.');
+    if (class_name_end != level_separator &&
+            !Common::ComparePartialString(class_name_end + 1, level_separator, "*")) {
+        class_name_end = level_separator;
+    }
+
+    const Class log_class = GetClassByName(begin, class_name_end);
+    if (log_class == Class::Count) {
+        LOG_ERROR(Log, "Unknown log class in filter: %s", std::string(begin, end).c_str());
+        return false;
+    }
+
+    if (class_name_end == level_separator) {
+        SetClassLevel(log_class, level);
+    }
+    SetSubclassesLevel(log_class, level);
+    return true;
+}
+
+bool Filter::CheckMessage(Class log_class, Level level) const {
+    return static_cast<u8>(level) >= static_cast<u8>(class_levels[static_cast<size_t>(log_class)]);
+}
+
+}