git-for-windows · dscho · Oct 10, 2025 · Jul 15, 2025 · Jul 16, 2025 · Jul 16, 2025
diff --git a/newlib/libc/stdio/fclose.c b/newlib/libc/stdio/fclose.c
@@ -72,13 +72,15 @@ _fclose_r (struct _reent *rptr,
   int __oldcancel;
   pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &__oldcancel);
 #endif
+  __sfp_lock_acquire ();
   if (!(fp->_flags2 & __SNLK))
     _flockfile (fp);
 
   if (fp->_flags == 0)		/* not open! */
     {
       if (!(fp->_flags2 & __SNLK))
 	_funlockfile (fp);
+      __sfp_lock_release ();
 #ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
       pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
@@ -101,7 +103,6 @@ _fclose_r (struct _reent *rptr,
     FREEUB (rptr, fp);
   if (HASLB (fp))
     FREELB (rptr, fp);
-  __sfp_lock_acquire ();
   fp->_flags = 0;		/* release this FILE for reuse */
   if (!(fp->_flags2 & __SNLK))
     _funlockfile (fp);

diff --git a/newlib/libc/stdlib/mbtowc_r.c b/newlib/libc/stdlib/mbtowc_r.c
@@ -677,21 +677,6 @@ __utf8_mbtowc (struct _reent *r,
 	state->__count = 3;
       else if (n < (size_t)-1)
 	++n;
-      if (n < 4)
-	return -2;
-      ch = t[i++];
-      if (ch < 0x80 || ch > 0xbf)
-	{
-	  _REENT_ERRNO(r) = EILSEQ;
-	  return -1;
-	}
-      /* Note: Originally we created the low surrogate pair on systems with
-	 wchar_t == UTF-16 *before* checking the 4th byte.  This was utterly
-	 wrong, because this failed to check the last byte for being a valid
-	 value for a complete UTF-8 4 byte sequence.  As a result, calling
-	 functions happily digested the low surrogate and then got an entirely
-	 different character and handled this separately, thus generating
-	 invalid UTF-16 values. */
       if (state->__count == 3 && sizeof(wchar_t) == 2)
 	{
 	  /* On systems which have wchar_t being UTF-16 values, the value
@@ -710,7 +695,15 @@ __utf8_mbtowc (struct _reent *r,
 	    |   (wint_t)((state->__value.__wchb[2] & 0x3f) << 6);
 	  state->__count = 4;
 	  *pwc = 0xd800 | ((tmp - 0x10000) >> 10);
-	  return 3;
+	  return i;
+	}
+      if (n < 4)
+	return -2;
+      ch = t[i++];
+      if (ch < 0x80 || ch > 0xbf)
+	{
+	  _REENT_ERRNO(r) = EILSEQ;
+	  return -1;
 	}
       tmp = (wint_t)((state->__value.__wchb[0] & 0x07) << 18)
 	|   (wint_t)((state->__value.__wchb[1] & 0x3f) << 12)

diff --git a/winsup/cygwin/clock.cc b/winsup/cygwin/clock.cc
@@ -32,22 +32,19 @@ system_tickcount_period ()
 void inline
 clk_t::init ()
 {
-  if (!period)
-    InterlockedExchange64 (&period, system_tickcount_period ());
+  InterlockedCompareExchange64 (&period, system_tickcount_period (), 0);
 }
 
 void inline
 clk_realtime_t::init ()
 {
-  if (!ticks_per_sec)
-    InterlockedExchange64 (&ticks_per_sec, system_qpc_tickspersec ());
+  InterlockedCompareExchange64 (&ticks_per_sec, system_qpc_tickspersec (), 0);
 }
 
 void inline
 clk_monotonic_t::init ()
 {
-  if (!ticks_per_sec)
-    InterlockedExchange64 (&ticks_per_sec, system_qpc_tickspersec ());
+  InterlockedCompareExchange64 (&ticks_per_sec, system_qpc_tickspersec (), 0);
 }
 
 int

diff --git a/winsup/cygwin/fhandler/base.cc b/winsup/cygwin/fhandler/base.cc
@@ -474,6 +474,9 @@ fhandler_base::open_with_arch (int flags, mode_t mode)
       if (!open_setup (flags))
 	api_fatal ("open_setup failed, %E");
     }
+  /* For pty and console, PATH_OPEN flag has not been set in open().
+     So set it here unconditionally. */
+  pc.set_isopen ();
 
   close_on_exec (flags & O_CLOEXEC);
   /* A unique ID is necessary to recognize fhandler entries which are

diff --git a/winsup/cygwin/fhandler/pty.cc b/winsup/cygwin/fhandler/pty.cc
@@ -693,8 +693,7 @@ fhandler_pty_master::process_slave_output (char *buf, size_t len, int pktmode_on
 
       termios_printf ("bytes read %u", n);
 
-      if (!buf || ((get_ttyp ()->ti.c_lflag & FLUSHO)
-		   && !get_ttyp ()->mask_flusho))
+      if (!buf || (get_ttyp ()->ti.c_lflag & FLUSHO))
 	continue; /* Discard read data */
 
       memcpy (optr, outbuf, n);
@@ -714,8 +713,6 @@ fhandler_pty_master::process_slave_output (char *buf, size_t len, int pktmode_on
     }
 
 out:
-  if (buf)
-    set_mask_flusho (false);
   termios_printf ("returning %d", rc);
   return rc;
 }
@@ -2258,7 +2255,6 @@ fhandler_pty_master::write (const void *ptr, size_t len)
 	      nlen--;
 	      i--;
 	    }
-	  process_stop_start (buf[i], get_ttyp ());
 	}
 
       DWORD n;

diff --git a/winsup/cygwin/fork.cc b/winsup/cygwin/fork.cc
@@ -329,6 +329,7 @@ frok::parent (volatile char * volatile stack_here)
   /* NEVER, EVER, call a function which in turn calls malloc&friends while this
      malloc lock is active! */
   __malloc_lock ();
+  cygheap->lock ();
   bool locked = true;
 
   /* Remove impersonation */
@@ -483,6 +484,7 @@ frok::parent (volatile char * volatile stack_here)
 		   impure, impure_beg, impure_end,
 		   NULL);
 
+  cygheap->unlock ();
   __malloc_unlock ();
   locked = false;
   if (!rc)
@@ -568,7 +570,10 @@ frok::parent (volatile char * volatile stack_here)
   if (fix_impersonation)
     cygheap->user.reimpersonate ();
   if (locked)
-    __malloc_unlock ();
+    {
+      cygheap->unlock ();
+      __malloc_unlock ();
+    }
 
   /* Remember to de-allocate the fd table. */
   if (hchild)

diff --git a/winsup/cygwin/include/cygwin/version.h b/winsup/cygwin/include/cygwin/version.h
@@ -11,7 +11,7 @@ details. */
    changes to the DLL and is mainly informative in nature. */
 
 #define CYGWIN_VERSION_DLL_MAJOR 3006
-#define CYGWIN_VERSION_DLL_MINOR 4
+#define CYGWIN_VERSION_DLL_MINOR 5
 
 /* CYGWIN_VERSION_DLL_COMBINED gives us a single number representing the
    combined DLL major and minor numbers. */

diff --git a/winsup/cygwin/include/sys/termios.h b/winsup/cygwin/include/sys/termios.h
@@ -282,6 +282,12 @@ struct termios
   speed_t	c_ospeed;
 };
 
+struct winsize
+{
+  unsigned short ws_row, ws_col;
+  unsigned short ws_xpixel, ws_ypixel;
+};
+
 #define termio termios
 
 #ifdef __cplusplus
@@ -313,13 +319,6 @@ int tcsetwinsize(int fd, const struct winsize *winsz);
 #define cfgetospeed(tp)		((tp)->c_ospeed)
 #endif
 
-/* Extra stuff to make porting stuff easier.  */
-struct winsize
-{
-  unsigned short ws_row, ws_col;
-  unsigned short ws_xpixel, ws_ypixel;
-};
-
 #define TIOCGWINSZ (('T' << 8) | 1)
 #define TIOCSWINSZ (('T' << 8) | 2)
 #define TIOCLINUX  (('T' << 8) | 3)

diff --git a/winsup/cygwin/local_includes/child_info.h b/winsup/cygwin/local_includes/child_info.h
@@ -33,7 +33,7 @@ enum child_status
 #define EXEC_MAGIC_SIZE sizeof(child_info)
 
 /* Change this value if you get a message indicating that it is out-of-sync. */
-#define CURR_CHILD_INFO_MAGIC 0xacbf4682U
+#define CURR_CHILD_INFO_MAGIC 0x77f25a01U
 
 #include "pinfo.h"
 struct cchildren
@@ -149,6 +149,7 @@ class child_info_spawn: public child_info
 
   void cleanup ();
   child_info_spawn () {};
+  child_info_spawn (child_info_types);
   child_info_spawn (child_info_types, bool);
   void record_children ();
   void reattach_children ();

diff --git a/winsup/cygwin/local_includes/cygheap.h b/winsup/cygwin/local_includes/cygheap.h
@@ -499,6 +499,9 @@ struct threadlist_t
 
 struct init_cygheap: public mini_cygheap
 {
+private:
+  static SRWLOCK cygheap_protect;
+public:
   _cmalloc_entry *chain;
   char *buckets[NBUCKETS];
   UNICODE_STRING installation_root;
@@ -542,6 +545,8 @@ struct init_cygheap: public mini_cygheap
   threadlist_t *find_tls (int, bool&);
   sigset_t compute_sigblkmask ();
   void unlock_tls (threadlist_t *t) { if (t) ReleaseMutex (t->mutex); }
+  inline void lock () { AcquireSRWLockExclusive (&cygheap_protect); }
+  inline void unlock () { ReleaseSRWLockExclusive (&cygheap_protect); }
 };
 
 

diff --git a/winsup/cygwin/local_includes/fhandler.h b/winsup/cygwin/local_includes/fhandler.h
@@ -2622,7 +2622,6 @@ class fhandler_pty_master: public fhandler_pty_common
   }
   void get_master_thread_param (master_thread_param_t *p);
   void get_master_fwd_thread_param (master_fwd_thread_param_t *p);
-  void set_mask_flusho (bool m) { get_ttyp ()->mask_flusho = m; }
   bool need_send_ctrl_c_event ();
 };
 

diff --git a/winsup/cygwin/local_includes/path.h b/winsup/cygwin/local_includes/path.h
@@ -244,6 +244,7 @@ class path_conv
   int isopen () const {return path_flags & PATH_OPEN;}
   int isctty_capable () const {return path_flags & PATH_CTTY;}
   int follow_fd_symlink () const {return path_flags & PATH_RESOLVE_PROCFD;}
+  void set_isopen () {path_flags |= PATH_OPEN;}
   void set_cygexec (bool isset)
   {
     if (isset)

diff --git a/winsup/cygwin/local_includes/tty.h b/winsup/cygwin/local_includes/tty.h
@@ -135,7 +135,6 @@ class tty: public tty_min
   bool master_is_running_as_service;
   bool req_xfer_input;
   xfer_dir pty_input_state;
-  bool mask_flusho;
   bool discard_input;
   bool stop_fwd_thread;
 

diff --git a/winsup/cygwin/mm/cygheap.cc b/winsup/cygwin/mm/cygheap.cc
@@ -35,7 +35,7 @@ static mini_cygheap NO_COPY cygheap_dummy =
 init_cygheap NO_COPY *cygheap = (init_cygheap *) &cygheap_dummy;
 void NO_COPY *cygheap_max;
 
-static NO_COPY SRWLOCK cygheap_protect = SRWLOCK_INIT;
+SRWLOCK NO_COPY init_cygheap::cygheap_protect = SRWLOCK_INIT;
 
 struct cygheap_entry
 {
@@ -377,7 +377,7 @@ _cmalloc (unsigned size)
   if (b >= NBUCKETS)
     return NULL;
 
-  AcquireSRWLockExclusive (&cygheap_protect);
+  cygheap->lock ();
   if (cygheap->buckets[b])
     {
       rvc = (_cmalloc_entry *) cygheap->buckets[b];
@@ -389,27 +389,27 @@ _cmalloc (unsigned size)
       rvc = (_cmalloc_entry *) _csbrk (bucket_val[b] + sizeof (_cmalloc_entry));
       if (!rvc)
 	{
-	  ReleaseSRWLockExclusive (&cygheap_protect);
+	  cygheap->unlock ();
 	  return NULL;
 	}
 
       rvc->b = b;
       rvc->prev = cygheap->chain;
       cygheap->chain = rvc;
     }
-  ReleaseSRWLockExclusive (&cygheap_protect);
+  cygheap->unlock ();
   return rvc->data;
 }
 
 static void
 _cfree (void *ptr)
 {
-  AcquireSRWLockExclusive (&cygheap_protect);
+  cygheap->lock ();
   _cmalloc_entry *rvc = to_cmalloc (ptr);
   unsigned b = rvc->b;
   rvc->ptr = cygheap->buckets[b];
   cygheap->buckets[b] = (char *) rvc;
-  ReleaseSRWLockExclusive (&cygheap_protect);
+  cygheap->unlock ();
 }
 
 static void *

diff --git a/winsup/cygwin/path.cc b/winsup/cygwin/path.cc
@@ -2071,7 +2071,10 @@ symlink_native (const char *oldpath, path_conv &win32_newpath)
 	    e_old = wcpcpy (e_old, L"..\\"), num--;
 	  if (num > 0)
 	    e_old = wcpcpy (e_old, L"..");
-	  wcpcpy (e_old, c_old);
+	  if (e_old == final_oldpath->Buffer && c_old[0] == L'\0')
+	    wcpcpy (e_old, L".");
+	  else
+	    wcpcpy (e_old, c_old);
 	}
     }
 

diff --git a/winsup/cygwin/posix_timer.cc b/winsup/cygwin/posix_timer.cc
@@ -349,7 +349,9 @@ timer_tracker::settime (int flags, const itimerspec *new_value,
 		 / (NSPERSEC / NS100PERSEC);
 	  if (flags & TIMER_ABSTIME)
 	    {
-	      if (clock_id == CLOCK_REALTIME)
+	      if (clock_id == CLOCK_REALTIME_COARSE
+		  || clock_id == CLOCK_REALTIME
+		  || clock_id == CLOCK_REALTIME_ALARM)
 		DueTime.QuadPart = ts + FACTOR;
 	      else /* non-REALTIME clocks require relative DueTime. */
 		{

diff --git a/winsup/cygwin/release/3.6.5 b/winsup/cygwin/release/3.6.5
@@ -0,0 +1,33 @@
+Fixes:
+------
+
+- Fix two minor bugs in clock and POSIX timer handling.
+
+- Fix an ordering problem in sys/termios.h.
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-July/258474.html
+
+- Fix doxygen hang due to a deadlock between fclose() and fork().
+  Addresses: https://cygwin.com/pipermail/cygwin-apps/2025-May/044318.html
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-June/258323.html
+
+- Fix multi-thread safety of system().
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-June/258324.html
+
+- Revert fix handling of invalid 4 byte UTF-8 sequence. It was broken.
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-July/258513.html
+
+- Instead, fix internal conversion of filenames in case of an invalid
+  4 byte UTF-8 sequence.
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-June/258358.html
+
+- Make process_fd correctly handle pty and console.
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-May/258167.html
+
+- Fix Ctrl-O (FLUSHO) handling.
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-August/258717.html
+
+- Fix multi-thread safety of fork()/exec() by adding the same locking as was
+  done for spawn.
+  Addresses: https://cygwin.com/pipermail/cygwin/2025-September/258801.html
+
+- Fix native symlink to '.' (a regresison in 3.6.4)
diff --git a/winsup/cygwin/select.cc b/winsup/cygwin/select.cc
@@ -689,6 +689,8 @@ pipe_data_available (int fd, fhandler_base *fh, HANDLE h, int mode)
   return 0;
 }
 
+SRWLOCK ptym_peek_lock = SRWLOCK_INIT;
+
 static int
 peek_pipe (select_record *s, bool from_select)
 {
@@ -730,10 +732,19 @@ peek_pipe (select_record *s, bool from_select)
 	  gotone = s->read_ready = true;
 	  goto out;
 	}
+      if (fh->get_major () == DEV_PTYM_MAJOR)
+	AcquireSRWLockExclusive (&ptym_peek_lock);
       ssize_t n = pipe_data_available (s->fd, fh, h, PDA_READ);
       /* On PTY masters, check if input from the echo pipe is available. */
       if (n == 0 && fh->get_echo_handle ())
 	n = pipe_data_available (s->fd, fh, fh->get_echo_handle (), PDA_READ);
+      if (fh->get_major () == DEV_PTYM_MAJOR)
+	{
+	  fhandler_pty_master *fhm = (fhandler_pty_master *) fh;
+	  while (n > 0 && (fhm->tc ()->ti.c_lflag & FLUSHO))
+	    n = fhm->process_slave_output (NULL, n, 0); /* Discard pipe data */
+	  ReleaseSRWLockExclusive (&ptym_peek_lock);
+	}
 
       if (n == PDA_ERROR)
 	{
@@ -759,11 +770,6 @@ peek_pipe (select_record *s, bool from_select)
     }
 
 out:
-  if (fh->get_major () == DEV_PTYM_MAJOR)
-    {
-      fhandler_pty_master *fhm = (fhandler_pty_master *) fh;
-      fhm->set_mask_flusho (s->read_ready);
-    }
   h = fh->get_output_handle ();
   if (s->write_selected && dev != FH_PIPER)
     {