Make numerous improvements

- Python static hello world now 1.8mb
- Python static fully loaded now 10mb
- Python HTTPS client now uses MbedTLS
- Python REPL now completes import stmts
- Increase stack size for Python for now
- Begin synthesizing posixpath and ntpath
- Restore Python \N{UNICODE NAME} support
- Restore Python NFKD symbol normalization
- Add optimized code path for Intel SHA-NI
- Get more Python unit tests passing faster
- Get Python help() pagination working on NT
- Python hashlib now supports MbedTLS PBKDF2
- Make memcpy/memmove/memcmp/bcmp/etc. faster
- Add Mersenne Twister and Vigna to LIBC_RAND
- Provide privileged __printf() for error code
- Fix zipos opendir() so that it reports ENOTDIR
- Add basic chmod() implementation for Windows NT
- Add Cosmo's best functions to Python cosmo module
- Pin function trace indent depth to that of caller
- Show memory diagram on invalid access in MODE=dbg
- Differentiate stack overflow on crash in MODE=dbg
- Add stb_truetype and tools for analyzing font files
- Upgrade to UNICODE 13 and reduce its binary footprint
- COMPILE.COM now logs resource usage of build commands
- Start implementing basic poll() support on bare metal
- Set getauxval(AT_EXECFN) to GetModuleFileName() on NT
- Add descriptions to strerror() in non-TINY build modes
- Add COUNTBRANCH() macro to help with micro-optimizations
- Make error / backtrace / asan / memory code more unbreakable
- Add fast perfect C implementation of μ-Law and a-Law audio codecs
- Make strtol() functions consistent with other libc implementations
- Improve Linenoise implementation (see also github.com/jart/bestline)
- COMPILE.COM now suppresses stdout/stderr of successful build commands

libc/calls/unlinkat-nt.c

@@ -18,17 +18,29 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/internal.h"
 #include "libc/errno.h"
+#include "libc/nt/enum/fileflagandattributes.h"
+#include "libc/nt/enum/io.h"
 #include "libc/nt/errors.h"
 #include "libc/nt/files.h"
 #include "libc/nt/runtime.h"
+#include "libc/nt/struct/win32fileattributedata.h"
+#include "libc/nt/struct/win32finddata.h"
 #include "libc/nt/synchronization.h"
 #include "libc/sysv/consts/at.h"
 
-static textwindows int sys_unlink_nt(const char16_t *path) {
-  if (DeleteFile(path)) {
-    return 0;
+static textwindows bool IsDirectorySymlink(const char16_t *path) {
+  int64_t h;
+  struct NtWin32FindData data;
+  struct NtWin32FileAttributeData info;
+  if (GetFileAttributesEx(path, 0, &info) &&
+      ((info.dwFileAttributes & kNtFileAttributeDirectory) &&
+       (info.dwFileAttributes & kNtFileAttributeReparsePoint)) &&
+      (h = FindFirstFile(path, &data)) != -1) {
+    FindClose(h);
+    return data.dwReserved0 == kNtIoReparseTagSymlink ||
+           data.dwReserved0 == kNtIoReparseTagMountPoint;
   } else {
-    return __winerr();
+    return false;
   }
 }
 
@@ -54,6 +66,11 @@ static textwindows int sys_rmdir_nt(const char16_t *path) {
   return -1;
 }
 
+static textwindows int sys_unlink_nt(const char16_t *path) {
+  if (IsDirectorySymlink(path)) return sys_rmdir_nt(path);
+  return DeleteFile(path) ? 0 : __winerr();
+}
+
 textwindows int sys_unlinkat_nt(int dirfd, const char *path, int flags) {
   uint16_t path16[PATH_MAX];
   if (__mkntpathat(dirfd, path, 0, path16) == -1) return -1;