From 97c3472e6e854cc16f04b30f0211da0b9d453b58 Mon Sep 17 00:00:00 2001
From: Andrea Odetti <mariofutire@gmail.com>
Date: Sun, 28 Nov 2021 19:18:38 +0000
Subject: [PATCH] libretro: support relative paths in m3u playlists.

Signed-off-by: Andrea Odetti <mariofutire@gmail.com>
---
 source/frontends/libretro/CMakeLists.txt  |  2 ++
 source/frontends/libretro/diskcontrol.cpp | 19 +++++++++++--------
 source/frontends/libretro/diskcontrol.h   |  3 ++-
 source/frontends/libretro/environment.cpp |  2 --
 source/frontends/libretro/environment.h   |  2 --
 source/frontends/libretro/libretro.cpp    |  5 -----
 6 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/source/frontends/libretro/CMakeLists.txt b/source/frontends/libretro/CMakeLists.txt
index 514f96841..77c48a9fc 100644
--- a/source/frontends/libretro/CMakeLists.txt
+++ b/source/frontends/libretro/CMakeLists.txt
@@ -35,6 +35,8 @@ add_library(applewin_libretro SHARED
   ${HEADER_FILES}
   )
 
+target_compile_features(applewin_libretro PUBLIC cxx_std_17)
+
 target_include_directories(applewin_libretro PRIVATE
   libretro-common/include
   )
diff --git a/source/frontends/libretro/diskcontrol.cpp b/source/frontends/libretro/diskcontrol.cpp
index 2031e40d2..fd98b1f63 100644
--- a/source/frontends/libretro/diskcontrol.cpp
+++ b/source/frontends/libretro/diskcontrol.cpp
@@ -33,13 +33,15 @@ namespace ra2
 
   bool DiskControl::insertPlaylist(const std::string & filename)
   {
-    std::ifstream playlist(filename);
+    const std::filesystem::path path(filename);
+    std::ifstream playlist(path);
     if (!playlist)
     {
       return false;
     }
 
     myImages.clear();
+    const std::filesystem::path parent = path.parent_path();
 
     std::string line;
     while (std::getline(playlist, line))
@@ -47,7 +49,12 @@ namespace ra2
       // should we trim initial spaces?
       if (!line.empty() && line[0] != '#')
       {
-        myImages.push_back(line);
+        std::filesystem::path image(line);
+        if (image.is_relative())
+        {
+          image = parent / image;
+        }
+        myImages.push_back(image);
       }
     }
 
@@ -227,12 +234,8 @@ namespace ra2
   {
     if (index < myImages.size())
     {
-      size_t pos = myImages[index].rfind('/');
-      if (pos == std::string::npos)
-      {
-        pos = 0;
-      }
-      strncpy(label, myImages[index].c_str() + pos + 1, len);
+      const std::string filename = myImages[index].filename();
+      strncpy(label, filename.c_str(), len);
       label[len - 1] = 0;
       return true;
     }
diff --git a/source/frontends/libretro/diskcontrol.h b/source/frontends/libretro/diskcontrol.h
index f47be03da..938f75544 100644
--- a/source/frontends/libretro/diskcontrol.h
+++ b/source/frontends/libretro/diskcontrol.h
@@ -1,5 +1,6 @@
 #include <vector>
 #include <string>
+#include <filesystem>
 
 namespace ra2
 {
@@ -31,7 +32,7 @@ namespace ra2
     static void setInitialPath(unsigned index, const char *path);
 
   private:
-    std::vector<std::string> myImages;
+    std::vector<std::filesystem::path> myImages;
 
     bool myEjected;
     size_t myIndex;
diff --git a/source/frontends/libretro/environment.cpp b/source/frontends/libretro/environment.cpp
index d437fbf5b..7b1380f09 100644
--- a/source/frontends/libretro/environment.cpp
+++ b/source/frontends/libretro/environment.cpp
@@ -25,8 +25,6 @@ namespace ra2
   retro_audio_sample_t audio_cb;
   retro_audio_sample_batch_t audio_batch_cb;
 
-  std::string retro_base_directory;
-
   void display_message(const std::string & message)
   {
     retro_message rmsg;
diff --git a/source/frontends/libretro/environment.h b/source/frontends/libretro/environment.h
index 3f55b2cad..40760f851 100644
--- a/source/frontends/libretro/environment.h
+++ b/source/frontends/libretro/environment.h
@@ -15,8 +15,6 @@ namespace ra2
   extern retro_audio_sample_t audio_cb;
   extern retro_audio_sample_batch_t audio_batch_cb;
 
-  extern std::string retro_base_directory;
-
 #define MAX_PADS 1
 
   void display_message(const std::string & message);
diff --git a/source/frontends/libretro/libretro.cpp b/source/frontends/libretro/libretro.cpp
index c02e49caa..9f44a6498 100644
--- a/source/frontends/libretro/libretro.cpp
+++ b/source/frontends/libretro/libretro.cpp
@@ -106,11 +106,6 @@ namespace
 void retro_init(void)
 {
   ra2::log_cb(RETRO_LOG_INFO, "RA2: %s\n", __FUNCTION__);
-  const char *dir = NULL;
-  if (ra2::environ_cb(RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY, &dir) && dir)
-  {
-    ra2::retro_base_directory = dir;
-  }
 }
 
 void retro_deinit(void)