Improve compatibility with C++20's u8string()

kcat · Nov 22, 2024 · a2085cc · a2085cc
1 parent b27ef50
commit a2085cc
Show file tree

Hide file tree

Showing 3 changed files with 36 additions and 14 deletions.
diff --git a/alc/alconfig.cpp b/alc/alconfig.cpp
@@ -353,7 +353,8 @@ void ReadALConfig()
             path = fs::path{buffer};
             path /= L"alsoft.ini";
 
-            TRACE("Loading config %s...\n", path.u8string().c_str());
+            TRACE("Loading config %s...\n",
+                reinterpret_cast<const char*>(path.u8string().c_str()));
             if(std::ifstream f{path}; f.is_open())
                 LoadConfigFromFile(f);
         }
@@ -364,15 +365,15 @@ void ReadALConfig()
     if(!path.empty())
     {
         path /= L"alsoft.ini";
-        TRACE("Loading config %s...\n", path.u8string().c_str());
+        TRACE("Loading config %s...\n", reinterpret_cast<const char*>(path.u8string().c_str()));
         if(std::ifstream f{path}; f.is_open())
             LoadConfigFromFile(f);
     }
 
     if(auto confpath = al::getenv(L"ALSOFT_CONF"))
     {
         path = *confpath;
-        TRACE("Loading config %s...\n", path.u8string().c_str());
+        TRACE("Loading config %s...\n", reinterpret_cast<const char*>(path.u8string().c_str()));
         if(std::ifstream f{path}; f.is_open())
             LoadConfigFromFile(f);
     }
@@ -385,7 +386,7 @@ void ReadALConfig()
     namespace fs = std::filesystem;
     fs::path path{"/etc/openal/alsoft.conf"};
 
-    TRACE("Loading config %s...\n", path.u8string().c_str());
+    TRACE("Loading config %s...\n", reinterpret_cast<const char*>(path.u8string().c_str()));
     if(std::ifstream f{path}; f.is_open())
         LoadConfigFromFile(f);
 
@@ -410,12 +411,14 @@ void ReadALConfig()
         }
 
         if(!path.is_absolute())
-            WARN("Ignoring XDG config dir: %s\n", path.u8string().c_str());
+            WARN("Ignoring XDG config dir: %s\n",
+                reinterpret_cast<const char*>(path.u8string().c_str()));
         else
         {
             path /= "alsoft.conf";
 
-            TRACE("Loading config %s...\n", path.u8string().c_str());
+            TRACE("Loading config %s...\n",
+                reinterpret_cast<const char*>(path.u8string().c_str()));
             if(std::ifstream f{path}; f.is_open())
                 LoadConfigFromFile(f);
         }
@@ -442,7 +445,7 @@ void ReadALConfig()
         path = *homedir;
         path /= ".alsoftrc";
 
-        TRACE("Loading config %s...\n", path.u8string().c_str());
+        TRACE("Loading config %s...\n", reinterpret_cast<const char*>(path.u8string().c_str()));
         if(std::ifstream f{path}; f.is_open())
             LoadConfigFromFile(f);
     }
@@ -463,7 +466,7 @@ void ReadALConfig()
     }
     if(!path.empty())
     {
-        TRACE("Loading config %s...\n", path.u8string().c_str());
+        TRACE("Loading config %s...\n", reinterpret_cast<const char*>(path.u8string().c_str()));
         if(std::ifstream f{path}; f.is_open())
             LoadConfigFromFile(f);
     }
@@ -473,7 +476,7 @@ void ReadALConfig()
     {
         path /= "alsoft.conf";
 
-        TRACE("Loading config %s...\n", path.u8string().c_str());
+        TRACE("Loading config %s...\n", reinterpret_cast<const char*>(path.u8string().c_str()));
         if(std::ifstream f{path}; f.is_open())
             LoadConfigFromFile(f);
     }

diff --git a/common/alstring.h b/common/alstring.h
@@ -39,6 +39,21 @@ int case_compare(const std::string_view str0, const std::string_view str1) noexc
 [[nodiscard]]
 int case_compare(const std::wstring_view str0, const std::wstring_view str1) noexcept;
 
+/* C++20 changes path::u8string() to return a string using a new/distinct
+ * char8_t type for UTF-8 strings. However, support for this with standard
+ * string functions is totally inadequate, and we already hold UTF-8 with plain
+ * char strings. So this function is used to reinterpret a char8_t string as a
+ * char string_view.
+ */
+#if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201907L
+inline auto u8_as_char(const std::u8string_view str) -> std::string_view
+#else
+inline auto u8_as_char(const std::string_view str) -> std::string_view
+#endif
+{
+    return std::string_view{reinterpret_cast<const char*>(str.data()), str.size()};
+}
+
 } // namespace al
 
 #endif /* AL_STRING_H */
diff --git a/core/helpers.cpp b/core/helpers.cpp
@@ -16,6 +16,7 @@
 #include <mutex>
 #include <optional>
 #include <string>
+#include <string_view>
 #include <system_error>
 
 #include "almalloc.h"
@@ -44,16 +45,19 @@ void DirectorySearch(const std::filesystem::path &path, const std::string_view e
         if(!fs::exists(fpath))
             return;
 
-        TRACE("Searching %s for *%.*s\n", fpath.u8string().c_str(), al::sizei(ext), ext.data());
+        TRACE("Searching %s for *%.*s\n", reinterpret_cast<const char*>(fpath.u8string().c_str()),
+            al::sizei(ext), ext.data());
         for(auto&& dirent : fs::directory_iterator{fpath})
         {
             auto&& entrypath = dirent.path();
             if(!entrypath.has_extension())
                 continue;
 
-            if(fs::status(entrypath).type() == fs::file_type::regular
-                && al::case_compare(entrypath.extension().u8string(), ext) == 0)
-                results->emplace_back(entrypath.u8string());
+            if(fs::status(entrypath).type() != fs::file_type::regular)
+                continue;
+            const auto u8ext = entrypath.extension().u8string();
+            if(al::case_compare(al::u8_as_char(u8ext), ext) == 0)
+                results->emplace_back(al::u8_as_char(entrypath.u8string()));
         }
     }
     catch(std::exception& e) {
@@ -276,7 +280,7 @@ const PathNamePair &GetProcBinary()
                         continue;
                     if(auto path = std::filesystem::read_symlink(name); !path.empty())
                     {
-                        pathname = path.u8string();
+                        pathname = al::u8_as_char(path.u8string());
                         break;
                     }
                 }