WasmFS JS API: Implement utime (#19561)

Author: jameshu15869

emcc.py

@@ -2346,6 +2346,7 @@ def phase_linker_setup(options, state, newargs):
         '_wasmfs_chmod',
         '_wasmfs_fchmod',
         '_wasmfs_lchmod',
+        '_wasmfs_utime',
         '_wasmfs_llseek',
         '_wasmfs_identify',
         '_wasmfs_readlink',

src/library_wasmfs.js

@@ -161,7 +161,6 @@ FS.createPreloadedFile = FS_createPreloadedFile;
       var buffer = stringToUTF8OnStack(path);
       return __wasmfs_chdir(buffer);
     }),
-    // TODO: read
     read: (stream, buffer, offset, length, position) => {
       var seeking = typeof position != 'undefined';
 
@@ -251,7 +250,6 @@ FS.createPreloadedFile = FS_createPreloadedFile;
           ino: {{{ makeGetValue('statBuf', C_STRUCTS.stat.st_ino, "u53") }}}
       }
     },
-    // TODO: stat
     stat: (path) => {
       var statBuf = _malloc({{{ C_STRUCTS.stat.__size__ }}});
       FS.handleError(withStackSave(() => {
@@ -262,7 +260,6 @@ FS.createPreloadedFile = FS_createPreloadedFile;
 
       return stats;
     },
-    // TODO: lstat
     lstat: (path) => {
       var statBuf = _malloc({{{ C_STRUCTS.stat.__size__ }}});
       FS.handleError(withStackSave(() => {
@@ -291,13 +288,17 @@ FS.createPreloadedFile = FS_createPreloadedFile;
     // TDOO: chown
     // TODO: lchown
     // TODO: fchown
+    utime: (path, atime, mtime) => (
+      FS.handleError(withStackSave(() => (
+        __wasmfs_utime(stringToUTF8OnStack(path), atime, mtime)
+      )))
+    ),
     truncate: (path, len) => {
       return FS.handleError(withStackSave(() => (__wasmfs_truncate(stringToUTF8OnStack(path), {{{ splitI64('len') }}}))));
     },
     ftruncate: (fd, len) => {
       return FS.handleError(__wasmfs_ftruncate(fd, {{{ splitI64('len') }}}));
     },
-    // TODO: utime
     findObject: (path) => {
       var result = __wasmfs_identify(path);
       if (result == {{{ cDefs.ENOENT }}}) {

system/lib/wasmfs/js_api.cpp

@@ -246,6 +246,16 @@ int _wasmfs_close(int fd) {
   return __wasi_fd_close(fd);
 }
 
+int _wasmfs_utime(char *path, long atime_ms, long mtime_ms) {
+  struct timespec times[2];
+  times[0].tv_sec = atime_ms / 1000;
+  times[0].tv_nsec = (atime_ms % 1000) * 1000000;
+  times[1].tv_sec = mtime_ms / 1000;
+  times[1].tv_nsec = (mtime_ms % 1000) * 1000000;
+
+  return __syscall_utimensat(AT_FDCWD, (intptr_t)path, (intptr_t)times, 0);
+};
+
 int _wasmfs_stat(char* path, struct stat* statBuf) {
   return __syscall_stat64((intptr_t)path, (intptr_t)statBuf);
 }

test/fs/test_fs_js_api.c

@@ -326,6 +326,32 @@ void test_fs_truncate() {
     remove("truncatetest");
 }
 
+void test_fs_utime() {
+    EM_ASM(
+        FS.writeFile('utimetest', 'a=1\nb=2\n');
+    );
+
+    EM_ASM(
+        FS.utime('utimetest', 10500, 8000);
+    );
+    struct stat utimeStats;
+    stat("utimetest", &utimeStats);
+
+    assert(utimeStats.st_atime == 10);
+    assert(utimeStats.st_atim.tv_sec == 10);
+
+    // WasmFS correctly sets both times, but the legacy API sets both times to the max of atime and mtime.
+#if WASMFS
+    assert(utimeStats.st_mtime == 8);
+    assert(utimeStats.st_mtim.tv_sec == 8);
+#else
+    assert(utimeStats.st_mtime == 10);
+    assert(utimeStats.st_mtim.tv_sec == 10);
+#endif
+
+    remove("utimetest");
+}
+
 void cleanup() {
     remove("testfile");
     remove("renametestfile");
@@ -336,12 +362,14 @@ void cleanup() {
 int main() {
     test_fs_open();
     test_fs_rename();
+    test_fs_readlink();
     test_fs_read();
     test_fs_rmdir();
     test_fs_close();
     test_fs_mknod();
     test_fs_allocate();
     test_fs_truncate();
+    test_fs_utime();
 
     cleanup();
 

test/other/metadce/test_metadce_cxx_wasmfs.size

@@ -1 +1 @@
-163996
+164034