Change loader log file location

Also apply upstream patch to fix Windows directory creation

Resolves: VLCLJ-2205

Signed-off-by: Jemale Lockett <[email protected]>

Author: Jemale

README.md

@@ -44,12 +44,17 @@ This will enforce the Loader to print all errors whether fatal or non-fatal to s
 The Level Zero Loader uses spdlog logging and can be controlled via environment variables:
 
 `ZEL_ENABLE_LOADER_LOGGING=1`
-`ZEL_LOADER_LOG_FILE=/path/to/logfile`
+
+[DEPRECATED] `ZEL_LOADER_LOG_FILE=/path/to/logfile`
+
+`ZEL_LOADER_LOG_DIR='/directory/path'`
+
 `ZEL_LOADER_LOGGING_LEVEL=debug`
 
 Valid logging levels are trace, debug, info, warn, error, critical, off.
 Logging is disabled by default but when enabled the default level is 'warn'.
-The default log file is 'ze_loader.log' in the current directory
+The default log file is 'ze_loader.log' in '.oneapi_logs' in the current
+user's home directory.
 
 This feature is in early development and is preview only.
 

source/loader/ze_loader.cpp

@@ -10,6 +10,12 @@
 #include "driver_discovery.h"
 #include <iostream>
 
+#ifdef __linux__
+#include <unistd.h>
+#include <sys/types.h>
+#include <pwd.h>
+#endif // __linux__
+
 namespace loader
 {
     ///////////////////////////////////////////////////////////////////////////////
@@ -261,16 +267,49 @@ namespace loader
         auto discoveredDrivers = discoverEnabledDrivers();
         std::string loadLibraryErrorValue;
 
+        auto log_directory = getenv_string("ZEL_LOADER_LOG_DIR");
+        if (log_directory.empty()) {
+            std::string home_dir;
+#ifdef _WIN32
+            home_dir = getenv_string("USERPROFILE");
+            if (home_dir == ""){
+                auto home_drive = getenv_string("HOMEDRIVE");
+                auto home_path = getenv_string("HOMEPATH");
+                if ((home_drive != "") && (home_path != "")) {
+                    home_dir = home_drive + home_path;
+                } else {
+                    home_dir = ".";
+                }
+            }
+            log_directory = home_dir + "\\" + LOADER_LOG_FILE_DIRECTORY;
+#else
+            home_dir = getenv_string("HOME");
 
+            if (home_dir == "") {
+                auto pwdir = getpwuid(getuid())->pw_dir;
+                home_dir = (pwdir == NULL) ? "." : std::string(pwdir);
+            }
+            log_directory = home_dir + "/" + LOADER_LOG_FILE_DIRECTORY;
+#endif
+        }
         auto loader_file = getenv_string("ZEL_LOADER_LOG_FILE");
         if (loader_file.empty()){
-            loader_file = LOADER_LOG_FILE_DEFAULT;
+            loader_file = LOADER_LOG_FILE;
+        } else {
+            auto log_depr_msg = "ZEL_LOADER_LOG_FILE will be deprecated in a future release";
+            std::cout << log_depr_msg << std::endl;
         }
 
+        std::string full_log_file_path = "";
+#ifdef _WIN32
+        full_log_file_path = log_directory + "\\" + loader_file;
+#else
+        full_log_file_path = log_directory + "/" + loader_file;
+#endif
         auto logging_enabled = getenv_tobool( "ZEL_ENABLE_LOADER_LOGGING" );
 
         auto log_level = getenv_string("ZEL_LOADER_LOGGING_LEVEL");
-        zel_logger =  std::make_shared<Logger>("ze_loader", loader_file, !log_level.empty() ? log_level : "warn", logging_enabled);
+        zel_logger =  std::make_shared<Logger>("ze_loader", full_log_file_path, !log_level.empty() ? log_level : "warn", logging_enabled);
         if ((log_level == "trace") && !debugTraceEnabled) {
             debugTraceEnabled = true;
             zel_logger->log_to_console = false;

source/utils/logging.h

@@ -13,7 +13,8 @@
 #define FMT_HEADER_ONLY
 #endif
 
-#define LOADER_LOG_FILE_DEFAULT "ze_loader.log"
+#define LOADER_LOG_FILE "ze_loader.log"
+#define LOADER_LOG_FILE_DIRECTORY ".oneapi_logs"
 
 #include <iostream>
 #include <sstream>

third_party/spdlog_headers/spdlog/details/os-inl.h

@@ -534,6 +534,15 @@ SPDLOG_INLINE bool create_dir(const filename_t &path) {
         }
 
         auto subdir = path.substr(0, token_pos);
+#ifdef _WIN32
+        // if subdir is just a drive letter, add a slash e.g. "c:"=>"c:\",
+        // otherwise path_exists(subdir) returns false (issue #3079)
+        const bool is_drive = subdir.length() == 2 && subdir[1] == ':';
+        if (is_drive) {
+          subdir += '\\';
+          token_pos++;
+        }
+#endif
 
         if (!subdir.empty() && !path_exists(subdir) && !mkdir_(subdir)) {
             return false;  // return error if failed creating dir