Added portable file and directory operations (thanks @icculus!)

src/filesystem/SDL_filesystem.c

@@ -0,0 +1,91 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_internal.h"
+#include "SDL_sysfilesystem.h"
+
+void SDL_FileTimeToWindows(Sint64 ftime, Uint32 *low, Uint32 *high)
+{
+    const Sint64 delta_1601_epoch_s = 11644473600ull; // [seconds] (seconds between 1/1/1601 and 1/1/1970, 11644473600 seconds)
+
+    Sint64 cvt = (ftime + delta_1601_epoch_s) * (SDL_NS_PER_SECOND / 100ull); // [100ns] (adjust to epoch and convert nanoseconds to 1/100th nanosecond units).
+
+    // Windows FILETIME is unsigned, so if we're trying to show a timestamp from before before the
+    // Windows epoch, (Jan 1, 1601), clamp it to zero so it doesn't go way into the future.
+    if (cvt < 0) {
+        cvt = 0;
+    }
+
+    if (low) {
+        *low = (Uint32) cvt;
+    }
+
+    if (high) {
+        *high = (Uint32) (cvt >> 32);
+    }
+}
+
+int SDL_RemovePath(const char *path)
+{
+    if (!path) {
+        return SDL_InvalidParamError("path");
+    }
+    return SDL_SYS_FSremove(path);
+}
+
+int SDL_RenamePath(const char *oldpath, const char *newpath)
+{
+    if (!oldpath) {
+        return SDL_InvalidParamError("oldpath");
+    } else if (!newpath) {
+        return SDL_InvalidParamError("newpath");
+    }
+    return SDL_SYS_FSrename(oldpath, newpath);
+}
+
+int SDL_CreateDirectory(const char *path)
+{
+    /* TODO: Recursively create subdirectories */
+    if (!path) {
+        return SDL_InvalidParamError("path");
+    }
+    return SDL_SYS_FSmkdir(path);
+}
+
+int SDL_EnumerateDirectory(const char *path, SDL_EnumerateDirectoryCallback callback, void *userdata)
+{
+    if (!path) {
+        return SDL_InvalidParamError("path");
+    } else if (!callback) {
+        return SDL_InvalidParamError("callback");
+    }
+    return SDL_SYS_FSenumerate(path, path, callback, userdata);
+}
+
+int SDL_GetPathInfo(const char *path, SDL_PathInfo *stat)
+{
+    if (!path) {
+        return SDL_InvalidParamError("path");
+    } else if (!stat) {
+        return SDL_InvalidParamError("stat");
+    }
+    return SDL_SYS_FSstat(path, stat);
+}