filesystem: fix resolving case sensitive paths

Resolves #2504 and #1934.

docs/tr1/CHANGELOG.md

@@ -1,6 +1,7 @@
 ## [Unreleased](https://github.com/LostArtefacts/TRX/compare/tr1-4.8.1...develop) - ××××-××-××
 - changed default FPS value to 60 (#2501)
 - fixed story so far not skipping over levels (#2506, regression from 4.8)
+- fixed resolving paths (especially to music files) on case-sensitive filesystems (#1934, #2504)
 - improved memory usage by shedding ca. 100-110 MB on average
 
 ## [4.8.1](https://github.com/LostArtefacts/TRX/compare/tr1-4.8...tr1-4.8.1) - 2025-02-14

docs/tr2/CHANGELOG.md

@@ -1,4 +1,5 @@
 ## [Unreleased](https://github.com/LostArtefacts/TRX/compare/tr2-0.9...develop) - ××××-××-××
+- fixed resolving paths (especially to music files) on case-sensitive filesystems (#1934, #2504)
 - improved memory usage by shedding ca. 100-110 MB on average
 
 ## [0.9](https://github.com/LostArtefacts/TRX/compare/tr2-0.8...tr2-0.9) - 2025-02-14

src/libtrx/filesystem.c

@@ -205,22 +205,31 @@ char *File_GetParentDirectory(const char *path)
 
 char *File_GuessExtension(const char *path, const char **extensions)
 {
-    if (!File_Exists(path)) {
-        const char *dot = strrchr(path, '.');
-        if (dot) {
-            for (const char **ext = &extensions[0]; *ext; ext++) {
-                size_t out_size = dot - path + strlen(*ext) + 1;
-                char *out = Memory_Alloc(out_size);
-                strncpy(out, path, dot - path);
-                out[dot - path] = '\0';
-                strcat(out, *ext);
-                if (File_Exists(out)) {
-                    return out;
-                }
-                Memory_FreePointer(&out);
-            }
-        }
+    if (File_Exists(path)) {
+        goto fallback;
     }
+
+    const char *dot = strrchr(path, '.');
+    if (dot == nullptr) {
+        goto fallback;
+    }
+
+    for (const char **ext = &extensions[0]; *ext; ext++) {
+        size_t out_size = dot - path + strlen(*ext) + 1;
+        char *out = Memory_Alloc(out_size);
+        strncpy(out, path, dot - path);
+        out[dot - path] = '\0';
+        strcat(out, *ext);
+
+        char *full_path = File_GetFullPath(out);
+        Memory_FreePointer(&out);
+        if (M_ExistsRaw(full_path)) {
+            return full_path;
+        }
+        Memory_FreePointer(&full_path);
+    }
+
+fallback:
     return Memory_DupStr(path);
 }
 

src/tr2/game/music/music_backend_files.c

@@ -26,7 +26,7 @@ static char *M_GetTrackFileName(const char *base_dir, int32_t track)
     char file_path[64];
     sprintf(file_path, "%s/track%02d.flac", base_dir, track);
     char *result = File_GuessExtension(file_path, m_ExtensionsToTry);
-    if (!File_Exists(file_path)) {
+    if (!File_Exists(result)) {
         Memory_FreePointer(&result);
         sprintf(file_path, "%s/%d.flac", base_dir, track);
         result = File_GuessExtension(file_path, m_ExtensionsToTry);