From 6bfc90dfaf5a3f36926b0c4d139691216fd843cf Mon Sep 17 00:00:00 2001
From: Quinton Miller <nicetas.c@gmail.com>
Date: Mon, 1 Jan 2024 22:53:46 +0800
Subject: [PATCH] Support absolute paths in `CRYSTAL_INTERPRETER_LOADER_INFO`
 (#14147)

---
 src/compiler/crystal/interpreter/context.cr | 12 ++++--------
 src/compiler/crystal/loader/msvc.cr         | 16 +++++++++++++++-
 src/compiler/crystal/loader/unix.cr         |  1 +
 3 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/src/compiler/crystal/interpreter/context.cr b/src/compiler/crystal/interpreter/context.cr
index 94456b4cec0e..d597810b36de 100644
--- a/src/compiler/crystal/interpreter/context.cr
+++ b/src/compiler/crystal/interpreter/context.cr
@@ -410,13 +410,6 @@ class Crystal::Repl::Context
     args.delete("-lgc")
 
     Crystal::Loader.parse(args).tap do |loader|
-      if ENV["CRYSTAL_INTERPRETER_LOADER_INFO"]?.presence
-        STDERR.puts "Crystal::Loader loaded libraries:"
-        loader.loaded_libraries.each do |path|
-          STDERR.puts "      #{path}"
-        end
-      end
-
       # FIXME: Part 2: This is a workaround for initial integration of the interpreter:
       # We append a handle to the current executable (i.e. the compiler program)
       # to the loader's handle list. This gives the loader access to all the symbols in the compiler program,
@@ -426,7 +419,10 @@ class Crystal::Repl::Context
       loader.load_current_program_handle
 
       if ENV["CRYSTAL_INTERPRETER_LOADER_INFO"]?.presence
-        STDERR.puts "      current program handle"
+        STDERR.puts "Crystal::Loader loaded libraries:"
+        loader.loaded_libraries.each do |path|
+          STDERR.puts "      #{path}"
+        end
       end
     end
   }
diff --git a/src/compiler/crystal/loader/msvc.cr b/src/compiler/crystal/loader/msvc.cr
index d4b899db0e87..e9fdc9af5bbd 100644
--- a/src/compiler/crystal/loader/msvc.cr
+++ b/src/compiler/crystal/loader/msvc.cr
@@ -139,7 +139,7 @@ class Crystal::Loader
       return false unless handle
 
       @handles << handle
-      @loaded_libraries << dll
+      @loaded_libraries << (module_filename(handle) || dll)
     end
 
     true
@@ -162,6 +162,7 @@ class Crystal::Loader
   def load_current_program_handle
     if LibC.GetModuleHandleExW(0, nil, out hmodule) != 0
       @handles << hmodule
+      @loaded_libraries << (Process.executable_path || "current program handle")
     end
   end
 
@@ -172,6 +173,19 @@ class Crystal::Loader
     @handles.clear
   end
 
+  private def module_filename(handle)
+    Crystal::System.retry_wstr_buffer do |buffer, small_buf|
+      len = LibC.GetModuleFileNameW(handle, buffer, buffer.size)
+      if 0 < len < buffer.size
+        break String.from_utf16(buffer[0, len])
+      elsif small_buf && len == buffer.size
+        next 32767 # big enough. 32767 is the maximum total path length of UNC path.
+      else
+        break nil
+      end
+    end
+  end
+
   # Returns a list of directories used as the default search paths.
   #
   # For MSVC this is simply the contents of the `LIB` environment variable,
diff --git a/src/compiler/crystal/loader/unix.cr b/src/compiler/crystal/loader/unix.cr
index 4c202231d7e6..39fef6e0c318 100644
--- a/src/compiler/crystal/loader/unix.cr
+++ b/src/compiler/crystal/loader/unix.cr
@@ -120,6 +120,7 @@ class Crystal::Loader
   def load_current_program_handle
     if program_handle = LibC.dlopen(nil, LibC::RTLD_LAZY | LibC::RTLD_GLOBAL)
       @handles << program_handle
+      @loaded_libraries << (Process.executable_path || "current program handle")
     end
   end