Merge pull request #743 from lioncash/view

logging: Use std::string_view where applicable

src/common/logging/backend.cpp

@@ -3,19 +3,20 @@
 // Refer to the license.txt file included.
 
 #include <algorithm>
-#include <array>
+#include <atomic>
 #include <chrono>
 #include <climits>
 #include <condition_variable>
 #include <memory>
+#include <mutex>
 #include <thread>
+#include <vector>
 #ifdef _WIN32
 #include <share.h> // For _SH_DENYWR
 #else
 #define _SH_DENYWR 0
 #endif
 #include "common/assert.h"
-#include "common/common_funcs.h" // snprintf compatibility define
 #include "common/logging/backend.h"
 #include "common/logging/log.h"
 #include "common/logging/text_formatter.h"
@@ -48,11 +49,11 @@ public:
         backends.push_back(std::move(backend));
     }
 
-    void RemoveBackend(const std::string& backend_name) {
+    void RemoveBackend(std::string_view backend_name) {
         std::lock_guard<std::mutex> lock(writing_mutex);
-        auto it = std::remove_if(backends.begin(), backends.end(), [&backend_name](const auto& i) {
+        const auto it =
-            return !strcmp(i->GetName(), backend_name.c_str());
+            std::remove_if(backends.begin(), backends.end(),
-        });
+                           [&backend_name](const auto& i) { return backend_name == i->GetName(); });
         backends.erase(it, backends.end());
     }
 
@@ -64,10 +65,10 @@ public:
         filter = f;
     }
 
-    Backend* GetBackend(const std::string& backend_name) {
+    Backend* GetBackend(std::string_view backend_name) {
-        auto it = std::find_if(backends.begin(), backends.end(), [&backend_name](const auto& i) {
+        const auto it =
-            return !strcmp(i->GetName(), backend_name.c_str());
+            std::find_if(backends.begin(), backends.end(),
-        });
+                         [&backend_name](const auto& i) { return backend_name == i->GetName(); });
         if (it == backends.end())
             return nullptr;
         return it->get();
@@ -265,11 +266,11 @@ void AddBackend(std::unique_ptr<Backend> backend) {
     Impl::Instance().AddBackend(std::move(backend));
 }
 
-void RemoveBackend(const std::string& backend_name) {
+void RemoveBackend(std::string_view backend_name) {
     Impl::Instance().RemoveBackend(backend_name);
 }
 
-Backend* GetBackend(const std::string& backend_name) {
+Backend* GetBackend(std::string_view backend_name) {
     return Impl::Instance().GetBackend(backend_name);
 }
 

src/common/logging/backend.h

@@ -4,10 +4,9 @@
 #pragma once
 
 #include <chrono>
-#include <cstdarg>
 #include <memory>
 #include <string>
-#include <utility>
+#include <string_view>
 #include "common/file_util.h"
 #include "common/logging/filter.h"
 #include "common/logging/log.h"
@@ -106,9 +105,9 @@ private:
 
 void AddBackend(std::unique_ptr<Backend> backend);
 
-void RemoveBackend(const std::string& backend_name);
+void RemoveBackend(std::string_view backend_name);
 
-Backend* GetBackend(const std::string& backend_name);
+Backend* GetBackend(std::string_view backend_name);
 
 /**
  * Returns the name of the passed log class as a C-string. Subclasses are separated by periods

src/common/logging/filter.cpp

@@ -8,39 +8,9 @@
 #include "common/string_util.h"
 
 namespace Log {
-
+namespace {
-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::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) {
+Level GetLevelByName(const It begin, const It end) {
     for (u8 i = 0; i < static_cast<u8>(Level::Count); ++i) {
         const char* level_name = GetLevelName(static_cast<Level>(i));
         if (Common::ComparePartialString(begin, end, level_name)) {
@@ -51,7 +21,7 @@ static Level GetLevelByName(const It begin, const It end) {
 }
 
 template <typename It>
-static Class GetClassByName(const It begin, const It end) {
+Class GetClassByName(const It begin, const It end) {
     for (ClassType i = 0; i < static_cast<ClassType>(Class::Count); ++i) {
         const char* level_name = GetLogClassName(static_cast<Class>(i));
         if (Common::ComparePartialString(begin, end, level_name)) {
@@ -61,8 +31,8 @@ static Class GetClassByName(const It begin, const It end) {
     return Class::Count;
 }
 
-bool Filter::ParseFilterRule(const std::string::const_iterator begin,
+template <typename Iterator>
-                             const std::string::const_iterator end) {
+bool ParseFilterRule(Filter& instance, Iterator begin, 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 `:`: {}",
@@ -77,7 +47,7 @@ bool Filter::ParseFilterRule(const std::string::const_iterator begin,
     }
 
     if (Common::ComparePartialString(begin, level_separator, "*")) {
-        ResetAll(level);
+        instance.ResetAll(level);
         return true;
     }
 
@@ -87,9 +57,40 @@ bool Filter::ParseFilterRule(const std::string::const_iterator begin,
         return false;
     }
 
-    SetClassLevel(log_class, level);
+    instance.SetClassLevel(log_class, level);
     return true;
 }
+} // Anonymous namespace
+
+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::ParseFilterString(std::string_view filter_view) {
+    auto clause_begin = filter_view.cbegin();
+    while (clause_begin != filter_view.cend()) {
+        auto clause_end = std::find(clause_begin, filter_view.cend(), ' ');
+
+        // If clause isn't empty
+        if (clause_end != clause_begin) {
+            ParseFilterRule(*this, clause_begin, clause_end);
+        }
+
+        if (clause_end != filter_view.cend()) {
+            // Skip over the whitespace
+            ++clause_end;
+        }
+        clause_begin = clause_end;
+    }
+}
 
 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)]);

src/common/logging/filter.h

@@ -6,7 +6,7 @@
 
 #include <array>
 #include <cstddef>
-#include <string>
+#include <string_view>
 #include "common/logging/log.h"
 
 namespace Log {
@@ -40,9 +40,7 @@ public:
      *  - `Service:Info` -- Sets the level of Service to Info.
      *  - `Service.FS:Trace` -- Sets the level of the Service.FS class to Trace.
      */
-    void ParseFilterString(const std::string& filter_str);
+    void ParseFilterString(std::string_view filter_view);
-    bool ParseFilterRule(const std::string::const_iterator start,
-                         const std::string::const_iterator end);
 
     /// Matches class/level combination against the filter, returning true if it passed.
     bool CheckMessage(Class log_class, Level level) const;