default paths to user and system db files on Windows

CMakeLists.txt

@@ -414,8 +414,13 @@ if(BUILD_DEV)
     set(MIOPEN_CACHE_DIR "" CACHE STRING "")
 else()
     set(MIOPEN_BUILD_DEV 0)
-    set(MIOPEN_USER_DB_PATH "~/.config/miopen/" CACHE STRING "Default path of user db files")
-    set(MIOPEN_CACHE_DIR "~/.cache/miopen/" CACHE STRING "")
+    if(WIN32)
+        set(MIOPEN_USER_DB_PATH "$USERPROFILE\\\\.miopen\\\\db\\\\" CACHE STRING "Default path to user db files")
+        set(MIOPEN_CACHE_DIR "$USERPROFILE\\\\.miopen\\\\cache\\\\" CACHE STRING "")
+    else()
+        set(MIOPEN_USER_DB_PATH "~/.config/miopen/" CACHE STRING "Default path of user db files")
+        set(MIOPEN_CACHE_DIR "~/.cache/miopen/" CACHE STRING "")
+    endif()
     set(MIOPEN_USER_DB_SUFFIX "${MIOPEN_BACKEND}.${MIOpen_VERSION_MAJOR}_${MIOpen_VERSION_MINOR}_${MIOpen_VERSION_PATCH}_${MIOpen_VERSION_TWEAK}" CACHE PATH "Filename suffix for the user find-db files")
 endif()
 set(MIOPEN_SYSTEM_FIND_DB_SUFFIX "${MIOPEN_BACKEND}" CACHE PATH "Filename suffix for the system find-db files")

src/db_path.cpp.in

@@ -42,10 +42,10 @@ MIOPEN_DECLARE_ENV_VAR_STR(MIOPEN_USER_DB_PATH)
 
 namespace miopen {
 
+#ifdef __linux__
 boost::filesystem::path GetLibPath()
 {
     boost::filesystem::path path = {""};
-#ifdef __linux__
     Dl_info info;
 
     if(dladdr(reinterpret_cast<void*>(miopenCreate), &info) != 0)
@@ -58,17 +58,17 @@ boost::filesystem::path GetLibPath()
         path = path.parent_path();
     }
     return path;
-#else
-    MIOPEN_THROW(miopenStatusNotImplemented);
-#endif
 }
+#endif
 
 std::string GetSystemDbPath()
 {
     auto p = GetStringEnv(ENV(MIOPEN_SYSTEM_DB_PATH));
     if(p.empty())
-#if MIOPEN_BUILD_DEV
+#if MIOPEN_BUILD_DEV || defined(_WIN32)
     {
+        // Here, by default, MIOPEN_SYSTEM_DB_PATH is an empty path on Windows.
+        // MIOpen.dll will be searching for System DB files in local directory.
         return "${MIOPEN_SYSTEM_DB_PATH}";
     }
 #else

src/expanduser.cpp

@@ -31,6 +31,10 @@
 #include <boost/filesystem.hpp>
 
 #include <string>
+#ifdef _WIN32
+#include <optional>
+#include <boost/algorithm/string/replace.hpp>
+#endif
 
 #ifdef __linux__
 #include <errno.h>
@@ -131,11 +135,9 @@ bool IsNetworked(unsigned long ft)
 } // namespace
 
 #undef CASE_RET_STRING
-#endif // __linux__
 
 bool IsNetworkedFilesystem(const boost::filesystem::path& path_)
 {
-#ifdef __linux__
     // Non-DEV builds put user databases in ~/.config/miopen by default; the binary cache is placed
     // in ~/.cache/miopen. If these directories do not exist, this is not a problem, because the
     // library creates them as needed.
@@ -172,10 +174,6 @@ bool IsNetworkedFilesystem(const boost::filesystem::path& path_)
     MIOPEN_LOG_NQI("Filesystem type at '" << path.string() << "' is: 0x" << std::hex << stat.f_type
                                           << " '" << Stringize(stat.f_type) << '\'');
     return IsNetworked(stat.f_type);
-#else
-    std::ignore = path_;
-    return false;
-#endif // __linux__
 }
 
 namespace {
@@ -200,4 +198,71 @@ boost::filesystem::path ExpandUser(const std::string& path)
     return {ReplaceString(path, "~", home_dir)};
 }
 
+#else
+
+namespace {
+std::optional<std::string> GetEnvironmentVariable(const std::string_view name)
+{
+    std::size_t required_size;
+    getenv_s(&required_size, nullptr, 0, name.data());
+    if(required_size == 0)
+    {
+        return std::nullopt;
+    }
+    // getenv_s returns the required size of a string including '\0' character.
+    std::string result(required_size - 1, 'A');
+    getenv_s(&required_size, result.data(), required_size, name.data());
+    return {result};
+}
+
+std::optional<std::pair<std::string::size_type, std::string>>
+ReplaceVariable(const std::string& path, std::string_view name, std::size_t offset = 0)
+{
+    std::vector<std::string> variables{
+        "$" + std::string{name}, "$env:" + std::string{name}, "%" + std::string{name} + "%"};
+    for(auto& variable : variables)
+    {
+        auto pos{path.find(variable, offset)};
+        if(pos != std::string::npos)
+        {
+            auto result{path};
+            auto value{GetEnvironmentVariable(name)};
+            if(!value)
+            {
+                // TODO: log warning message that the name used does not
+                //       correspond to an environment variable.
+                value = boost::filesystem::temp_directory_path().string();
+            }
+            result.replace(pos, variable.length(), *value);
+            return {{pos, result}};
+        }
+    }
+    return std::nullopt;
+}
+} // namespace
+
+boost::filesystem::path ExpandUser(const std::string& path)
+{
+    auto result{ReplaceVariable(path, "USERPROFILE")};
+    if(!result)
+    {
+        result = ReplaceVariable(path, "HOME");
+        if(!result)
+        {
+            result = ReplaceVariable(path, "HOMEDRIVE");
+            if(result)
+            {
+                result = ReplaceVariable(std::get<1>(*result), "HOMEPATH", std::get<0>(*result));
+                // TODO: if (not result): log warning message that
+                //       HOMEDRIVE and HOMEPATH work in conjunction, respectively.
+            }
+        }
+    }
+    return {!result ? path : std::get<1>(*result)};
+}
+
+bool IsNetworkedFilesystem(const boost::filesystem::path&) { return false; }
+
+#endif
+
 } // namespace miopen