Fix return value of VFS seek function (#18561)

white-axe · web-flow · commit 85ae584b09d2 · 2026-01-01T10:36:21.000+01:00
diff --git a/libretro-common/include/streams/file_stream_transforms.h b/libretro-common/include/streams/file_stream_transforms.h
@@ -89,7 +89,7 @@ int rfclose(RFILE* stream);
 int64_t rftell(RFILE* stream);
 
 /** @see https://en.cppreference.com/w/c/io/fseek */
-int64_t rfseek(RFILE* stream, int64_t offset, int origin);
+int rfseek(RFILE* stream, int64_t offset, int origin);
 
 /** @see https://en.cppreference.com/w/c/io/fread */
 int64_t rfread(void* buffer,
diff --git a/libretro-common/streams/file_stream_transforms.c b/libretro-common/streams/file_stream_transforms.c
@@ -83,7 +83,7 @@ int64_t rftell(RFILE* stream)
    return filestream_tell(stream);
 }
 
-int64_t rfseek(RFILE* stream, int64_t offset, int origin)
+int rfseek(RFILE* stream, int64_t offset, int origin)
 {
    int seek_position = -1;
 
@@ -103,7 +103,7 @@ int64_t rfseek(RFILE* stream, int64_t offset, int origin)
          break;
    }
 
-   return filestream_seek(stream, offset, seek_position);
+   return filestream_seek(stream, offset, seek_position) == -1 ? -1 : 0;
 }
 
 int64_t rfread(void* buffer,
diff --git a/libretro-common/vfs/vfs_implementation.c b/libretro-common/vfs/vfs_implementation.c
@@ -242,11 +242,23 @@ int64_t retro_vfs_file_seek_internal(
 #endif
 #ifdef ATLEAST_VC2005
       /* VC2005 and up have a special 64-bit fseek */
-      return _fseeki64(stream->fp, offset, whence);
+      if (_fseeki64(stream->fp, offset, whence) != 0)
+         return -1;
+      if ((val = _ftelli64(stream->fp)) < 0)
+         return -1;
+      return val;
 #elif defined(HAVE_64BIT_OFFSETS)
-      return fseeko(stream->fp, (off_t)offset, whence);
+      if (fseeko(stream->fp, (off_t)offset, whence) != 0)
+         return -1;
+      if ((val = ftello(stream->fp)) < 0)
+         return -1;
+      return val;
 #else
-      return fseek(stream->fp, (long)offset, whence);
+      if (fseek(stream->fp, (long)offset, whence) != 0)
+         return -1;
+      if ((val = ftell(stream->fp)) < 0)
+         return -1;
+      return val;
 #endif
    }
 #ifdef HAVE_MMAP
@@ -718,11 +730,17 @@ int64_t retro_vfs_file_tell_impl(libretro_vfs_implementation_file *stream)
 #endif
 #ifdef ATLEAST_VC2005
       /* VC2005 and up have a special 64-bit ftell */
-      return _ftelli64(stream->fp);
+      if ((val = _ftelli64(stream->fp)) < 0)
+         return -1;
+      return val;
 #elif defined(HAVE_64BIT_OFFSETS)
-      return ftello(stream->fp);
+      if ((val = ftello(stream->fp)) < 0)
+         return -1;
+      return val;
 #else
-      return ftell(stream->fp);
+      if ((val = ftell(stream->fp)) < 0)
+         return -1;
+      return val;
 #endif
    }
 #ifdef HAVE_MMAP
diff --git a/libretro-common/vfs/vfs_implementation_cdrom.c b/libretro-common/vfs/vfs_implementation_cdrom.c
@@ -21,6 +21,7 @@
 */
 
 #include <vfs/vfs_implementation.h>
+#include <vfs/vfs_implementation_cdrom.h>
 #include <file/file_path.h>
 #include <compat/fopen_utf8.h>
 #include <string/stdstring.h>
@@ -139,7 +140,7 @@ int64_t retro_vfs_file_seek_cdrom(
    else
       return -1;
 
-   return 0;
+   return retro_vfs_file_tell_cdrom(stream);
 }
 
 void retro_vfs_file_open_cdrom(
diff --git a/libretro-common/vfs/vfs_implementation_uwp.cpp b/libretro-common/vfs/vfs_implementation_uwp.cpp
@@ -136,30 +136,34 @@ int64_t retro_vfs_file_truncate_impl(libretro_vfs_implementation_file* stream, i
 
 int64_t retro_vfs_file_tell_impl(libretro_vfs_implementation_file* stream)
 {
+    int64_t val;
+
     if (!stream)
         return -1;
 
     if ((stream->hints & RFILE_HINT_UNBUFFERED) == 0)
         return _ftelli64(stream->fp);
-    if (lseek(stream->fd, 0, SEEK_CUR) < 0)
+    if ((val = lseek(stream->fd, 0, SEEK_CUR)) < 0)
         return -1;
 
-    return 0;
+    return val;
 }
 
 int64_t retro_vfs_file_seek_internal(
     libretro_vfs_implementation_file* stream,
     int64_t offset, int whence)
 {
+    int64_t val;
+
     if (!stream)
         return -1;
 
     if ((stream->hints & RFILE_HINT_UNBUFFERED) == 0)
         return _fseeki64(stream->fp, offset, whence);
-    if (lseek(stream->fd, (off_t)offset, whence) < 0)
+    if ((val = lseek(stream->fd, (off_t)offset, whence)) < 0)
         return -1;
 
-    return 0;
+    return val;
 }
 
 int64_t retro_vfs_file_seek_impl(libretro_vfs_implementation_file* stream,

Original file line number	Diff line number	Diff line change
`@@ -83,7 +83,7 @@ int64_t rftell(RFILE* stream)`
`83`	`83`	`return filestream_tell(stream);`
`84`	`84`	`}`
`85`	`85`
`86`		`-int64_t rfseek(RFILE* stream, int64_t offset, int origin)`
	`86`	`+int rfseek(RFILE* stream, int64_t offset, int origin)`
`87`	`87`	`{`
`88`	`88`	`int seek_position = -1;`
`89`	`89`
`@@ -103,7 +103,7 @@ int64_t rfseek(RFILE* stream, int64_t offset, int origin)`
`103`	`103`	`break;`
`104`	`104`	`}`
`105`	`105`
`106`		`- return filestream_seek(stream, offset, seek_position);`
	`106`	`+ return filestream_seek(stream, offset, seek_position) == -1 ? -1 : 0;`
`107`	`107`	`}`
`108`	`108`
`109`	`109`	`int64_t rfread(void* buffer,`