Rename library_exists_in_dir to file_exists_in_dir and remove som…

…e unnecessary string allocations (dotnet#95154)

src/native/corehost/fxr/framework_info.cpp

@@ -73,6 +73,7 @@ bool compare_by_name_and_version(const framework_info &a, const framework_info &
 
             trace::verbose(_X("Gathering FX locations in [%s]"), fx_dir.c_str());
 
+            const pal::string_t deps_file_name = fx_name_local + _X(".deps.json");
             std::vector<pal::string_t> versions;
             pal::readdir_onlydirectories(fx_dir, &versions);
             for (const pal::string_t& ver : versions)
@@ -85,7 +86,7 @@ bool compare_by_name_and_version(const framework_info &a, const framework_info &
                 // Check that the framework's .deps.json exists.
                 pal::string_t fx_version_dir = fx_dir;
                 append_path(&fx_version_dir, ver.c_str());
-                if (!library_exists_in_dir(fx_version_dir, fx_name_local + _X(".deps.json"), nullptr))
+                if (!file_exists_in_dir(fx_version_dir, deps_file_name.c_str(), nullptr))
                 {
                     trace::verbose(_X("Ignoring FX version [%s] without .deps.json"), ver.c_str());
                     continue;

src/native/corehost/fxr/fx_resolver.cpp

@@ -234,7 +234,7 @@ namespace
                     fx_ref.get_fx_version().c_str());
 
                 append_path(&fx_dir, fx_ref.get_fx_version().c_str());
-                if (library_exists_in_dir(fx_dir, deps_file_name, nullptr))
+                if (file_exists_in_dir(fx_dir, deps_file_name.c_str(), nullptr))
                 {
                     selected_fx_dir = fx_dir;
                     selected_fx_version = fx_ref.get_fx_version();
@@ -266,7 +266,7 @@ namespace
                     // Check that the framework's .deps.json exists. To minimize the file checks done in the most common
                     // scenario (.deps.json exists), only check after resolving the version and if the .deps.json doesn't
                     // exist, attempt resolving again without that version.
-                    if (!library_exists_in_dir(resolved_fx_dir, deps_file_name, nullptr))
+                    if (!file_exists_in_dir(resolved_fx_dir, deps_file_name.c_str(), nullptr))
                     {
                         // Remove the version and try resolving again
                         trace::verbose(_X("Ignoring FX version [%s] without .deps.json"), resolved_ver_str.c_str());

src/native/corehost/fxr/sdk_info.cpp

@@ -63,7 +63,7 @@ void sdk_info::enumerate_sdk_paths(
         // Check for the existence of dotnet.dll
         pal::string_t sdk_version_dir = sdk_dir;
         append_path(&sdk_version_dir, version_str.c_str());
-        if (!library_exists_in_dir(sdk_version_dir, SDK_DOTNET_DLL, nullptr))
+        if (!file_exists_in_dir(sdk_version_dir, SDK_DOTNET_DLL, nullptr))
         {
             trace::verbose(_X("Ignoring version [%s] without ") SDK_DOTNET_DLL, version_str.c_str());
             continue;

src/native/corehost/fxr/standalone/hostpolicy_resolver.cpp

@@ -76,7 +76,7 @@ namespace
         append_path(&path, rel_dir.c_str());                  // relative dir containing hostpolicy library
 
                                                             // Check if "path" contains the required library.
-        if (!library_exists_in_dir(path, LIBHOSTPOLICY_NAME, nullptr))
+        if (!file_exists_in_dir(path, LIBHOSTPOLICY_NAME, nullptr))
         {
             trace::verbose(_X("Did not find %s in directory %s"), LIBHOSTPOLICY_NAME, path.c_str());
             return false;
@@ -175,7 +175,7 @@ int hostpolicy_resolver::load(
     if (g_hostpolicy == nullptr)
     {
         pal::string_t host_path;
-        if (!library_exists_in_dir(lib_dir, LIBHOSTPOLICY_NAME, &host_path))
+        if (!file_exists_in_dir(lib_dir, LIBHOSTPOLICY_NAME, &host_path))
         {
             return StatusCode::CoreHostLibMissingFailure;
         }
@@ -289,7 +289,7 @@ bool hostpolicy_resolver::try_get_dir(
 
     // Check if hostpolicy exists in "expected" directory.
     trace::verbose(_X("The expected %s directory is [%s]"), LIBHOSTPOLICY_NAME, expected.c_str());
-    if (library_exists_in_dir(expected, LIBHOSTPOLICY_NAME, nullptr))
+    if (file_exists_in_dir(expected, LIBHOSTPOLICY_NAME, nullptr))
     {
         impl_dir->assign(expected);
         return true;

src/native/corehost/fxr_resolver.cpp

@@ -40,7 +40,7 @@ namespace
         append_path(&fxr_root, max_ver_str.c_str());
         trace::info(_X("Detected latest fxr version=[%s]..."), fxr_root.c_str());
 
-        if (library_exists_in_dir(fxr_root, LIBFXR_NAME, out_fxr_path))
+        if (file_exists_in_dir(fxr_root, LIBFXR_NAME, out_fxr_path))
         {
             trace::info(_X("Resolved fxr [%s]..."), out_fxr_path->c_str());
             return true;
@@ -58,7 +58,7 @@ bool fxr_resolver::try_get_path(const pal::string_t& root_path, pal::string_t* o
     // For apphost and libhost, root_path is expected to be a directory.
     // For libhost, it may be empty if app-local search is not desired (e.g. com/ijw/winrt hosts, nethost when no assembly path is specified)
     // If a hostfxr exists in root_path, then assume self-contained.
-    if (root_path.length() > 0 && library_exists_in_dir(root_path, LIBFXR_NAME, out_fxr_path))
+    if (root_path.length() > 0 && file_exists_in_dir(root_path, LIBFXR_NAME, out_fxr_path))
     {
         trace::info(_X("Resolved fxr [%s]..."), out_fxr_path->c_str());
         out_dotnet_root->assign(root_path);

src/native/corehost/hostmisc/utils.cpp

@@ -10,19 +10,17 @@
 #include <_version.c>
 #endif
 
-bool library_exists_in_dir(const pal::string_t& lib_dir, const pal::string_t& lib_name, pal::string_t* p_lib_path)
+bool file_exists_in_dir(const pal::string_t& dir, const pal::char_t* file_name, pal::string_t* out_file_path)
 {
-    pal::string_t lib_path = lib_dir;
-    append_path(&lib_path, lib_name.c_str());
+    pal::string_t file_path = dir;
+    append_path(&file_path, file_name);
 
-    if (!pal::file_exists(lib_path))
-    {
+    if (!pal::file_exists(file_path))
         return false;
-    }
-    if (p_lib_path)
-    {
-        *p_lib_path = lib_path;
-    }
+
+    if (out_file_path)
+        *out_file_path = file_path;
+
     return true;
 }
 

src/native/corehost/hostmisc/utils.h

@@ -87,7 +87,7 @@ pal::string_t strip_file_ext(const pal::string_t& path);
 pal::string_t get_filename(const pal::string_t& path);
 pal::string_t get_filename_without_ext(const pal::string_t& path);
 void append_path(pal::string_t* path1, const pal::char_t* path2);
-bool library_exists_in_dir(const pal::string_t& lib_dir, const pal::string_t& lib_name, pal::string_t* p_lib_path);
+bool file_exists_in_dir(const pal::string_t& dir, const pal::char_t* file_name, pal::string_t* out_file_path);
 bool coreclr_exists_in_dir(const pal::string_t& candidate);
 void remove_trailing_dir_separator(pal::string_t* dir);
 void replace_char(pal::string_t* path, pal::char_t match, pal::char_t repl);

src/native/corehost/hostpolicy/deps_resolver.cpp

@@ -835,7 +835,9 @@ bool deps_resolver_t::resolve_probe_dirs(
         // App local path
         add_unique_path(asset_type, m_app_dir, &items, output, &non_serviced, core_servicing);
 
-        (void) library_exists_in_dir(m_app_dir, LIBCORECLR_NAME, &m_coreclr_path);
+        // deps_resolver treats being able to get the coreclr path as optional, so we ignore the return value here.
+        // The caller is responsible for checking whether coreclr path is set and handling as appropriate.
+        (void) file_exists_in_dir(m_app_dir, LIBCORECLR_NAME, &m_coreclr_path);
     }
 
     // Handle any additional deps.json that were specified.