Fix #5507: RCT1 path check is case-sensitive on Linux

If the csg path does not exist, find the first file in the directory that matches (case insensitive).

src/openrct2/core/Path.cpp

@@ -14,6 +14,10 @@
  *****************************************************************************/
 #pragma endregion
 
+#ifndef _WIN32
+    #include <dirent.h>
+#endif
+
 extern "C"
 {
     #include "../platform/platform.h"
@@ -21,6 +25,7 @@ extern "C"
     #include "../util/util.h"
 }
 
+#include "File.h"
 #include "Math.hpp"
 #include "Memory.hpp"
 #include "Path.hpp"
@@ -218,4 +223,45 @@ namespace Path
 #endif
         return String::Equals(a, b, ignoreCase);
     }
+
+    std::string ResolveCasing(const std::string &path)
+    {
+        std::string result;
+        if (File::Exists(path))
+        {
+            // Windows is case insensitive so it will exist and that is all that matters
+            // for now. We can properly resolve the casing if we ever need to.
+            result = path;
+        }
+#ifndef _WIN32
+        else
+        {
+            std::string fileName = Path::GetFileName(path);
+            std::string directory = Path::GetDirectory(path);
+
+            struct dirent * * files;
+            auto count = scandir(directory.c_str(), &files, nullptr, alphasort);
+            if (count != -1)
+            {
+                // Find a file which matches by name (case insensitive)
+                for (sint32 i = 0; i < count; i++)
+                {
+                    if (String::Equals(files[i]->d_name, fileName.c_str(), true))
+                    {
+                        result = Path::Combine(directory, std::string(files[i]->d_name));
+                        break;
+                    }
+                }
+
+                // Free memory
+                for (sint32 i = 0; i < count; i++)
+                {
+                    free(files[i]);
+                }
+                free(files);
+            }
+        }
+#endif
+        return result;
+    }
 }

src/openrct2/core/Path.hpp

@@ -43,4 +43,12 @@ namespace Path
     utf8 * GetAbsolute(utf8 * buffer, size_t bufferSize, const utf8 * relativePath);
     bool Equals(const std::string &a, const std::string &b);
     bool Equals(const utf8 * a, const utf8 * b);
+
+    /**
+     * Checks if the given path is a file. If not, checks to see if
+     * there are any files with different casing and selects the first
+     * one found based on a straight forward character sort.
+     * Note: This will not resolve the case for Windows.
+     */
+    std::string ResolveCasing(const std::string &path);
 }

src/openrct2/drawing/sprite.cpp

@@ -21,6 +21,7 @@
 #include "../core/File.h"
 #include "../core/FileStream.hpp"
 #include "../core/Memory.hpp"
+#include "../core/Path.hpp"
 #include "../core/Util.hpp"
 #include "../OpenRCT2.h"
 #include "../sprites.h"
@@ -188,6 +189,37 @@ extern "C"
         return false;
     }
 
+    static utf8 * gfx_get_csg_header_path()
+    {
+        char path[MAX_PATH];
+        safe_strcpy(path, gConfigGeneral.rct1_path, sizeof(path));
+        safe_strcat_path(path, "Data", sizeof(path));
+        safe_strcat_path(path, "csg1i.dat", sizeof(path));
+        return String::Duplicate(Path::ResolveCasing(path));
+    }
+
+    static utf8 * gfx_get_csg_data_path()
+    {
+        // csg1.1 and csg1.dat are the same file.
+        // In the CD version, it's called csg1.1 on the CD and csg1.dat on the disk.
+        // In the GOG version, it's always called csg1.1.
+        // In the Steam version, it's always called csg1.dat.
+        char path[MAX_PATH];
+        safe_strcpy(path, gConfigGeneral.rct1_path, sizeof(path));
+        safe_strcat_path(path, "Data", sizeof(path));
+        safe_strcat_path(path, "csg1.1", sizeof(path));
+
+        auto fixedPath = Path::ResolveCasing(path);
+        if (fixedPath.empty())
+        {
+            safe_strcpy(path, gConfigGeneral.rct1_path, sizeof(path));
+            safe_strcat_path(path, "Data", sizeof(path));
+            safe_strcat_path(path, "csg1.dat", sizeof(path));
+            fixedPath = Path::ResolveCasing(path);
+        }
+        return String::Duplicate(fixedPath);
+    }
+
     bool gfx_load_csg()
     {
         log_verbose("gfx_load_csg()");
@@ -198,31 +230,12 @@ extern "C"
             return false;
         }
 
-        char pathHeader[MAX_PATH];
-        safe_strcpy(pathHeader, gConfigGeneral.rct1_path, sizeof(pathHeader));
-        safe_strcat_path(pathHeader, "Data", sizeof(pathHeader));
-        safe_strcat_path(pathHeader, "csg1i.dat", sizeof(pathHeader));
-
-        // csg1.1 and csg1.dat are the same file.
-        // In the CD version, it's called csg1.1 on the CD and csg1.dat on the disk.
-        // In the GOG version, it's always called csg1.1.
-        // In the Steam version, it's always called csg1.dat.
-        char pathData[MAX_PATH];
-        safe_strcpy(pathData, gConfigGeneral.rct1_path, sizeof(pathData));
-        safe_strcat_path(pathData, "Data", sizeof(pathData));
-        safe_strcat_path(pathData, "csg1.1", sizeof(pathData));
-
-        if (!File::Exists(pathData))
-        {
-            safe_strcpy(pathData, gConfigGeneral.rct1_path, sizeof(pathData));
-            safe_strcat_path(pathData, "Data", sizeof(pathData));
-            safe_strcat_path(pathData, "csg1.dat", sizeof(pathData));
-        }
-
+        auto pathHeaderPath = std::unique_ptr<utf8>(gfx_get_csg_header_path());
+        auto pathDataPath = std::unique_ptr<utf8>(gfx_get_csg_data_path());
         try
         {
-            auto fileHeader = FileStream(pathHeader, FILE_MODE_OPEN);
-            auto fileData = FileStream(pathData, FILE_MODE_OPEN);
+            auto fileHeader = FileStream(pathHeaderPath.get(), FILE_MODE_OPEN);
+            auto fileData = FileStream(pathDataPath.get(), FILE_MODE_OPEN);
             size_t fileHeaderSize = fileHeader.GetLength();
             size_t fileDataSize = fileData.GetLength();