wip

Author: YO4

include/ruby/win32.h

@@ -328,6 +328,16 @@ extern rb_pid_t rb_w32_uaspawn_flags(int, const char *, char *const *, DWORD);
 extern int kill(rb_pid_t, int);
 extern int fcntl(int, int, ...);
 extern int rb_w32_set_nonblock(int);
+/* Accessor for the CRT internal _osfile array so that the inherit
+ * table builder in process.c can read the FNOINHERIT bit set by
+ * fcntl(F_SETFD, FD_CLOEXEC). */
+extern unsigned char rb_w32_get_osfile(int);
+/* Mirror of fcntl(fd, F_SETFD, FD_CLOEXEC / cleared) on Windows.
+ * Sets both the OS HANDLE_FLAG_INHERIT bit and the CRT _osfile
+ * FNOINHERIT bit so non-standard fds are not inherited by child
+ * processes unless explicitly requested.  Returns 0 on success, -1
+ * (with errno set) if SetHandleInformation fails. */
+extern int rb_w32_set_cloexec(int fd, int cloexec);
 extern rb_pid_t rb_w32_getpid(void);
 extern rb_pid_t rb_w32_getppid(void);
 extern int rb_w32_isatty(int);

internal/io.h

@@ -151,6 +151,8 @@ VALUE rb_io_prep_stderr(void);
 int rb_io_notify_close(struct rb_io *fptr);
 bool rb_io_fptr_finalize_closed(struct rb_io *fptr);
 
+int rb_get_max_fd(void);
+
 RUBY_SYMBOL_EXPORT_BEGIN
 /* io.c (export) */
 void rb_maygvl_fd_fix_cloexec(int fd);

internal/process.h

@@ -100,6 +100,17 @@ VALUE rb_execarg_extract_options(VALUE execarg_obj, VALUE opthash);
 void rb_execarg_setenv(VALUE execarg_obj, VALUE env);
 RUBY_SYMBOL_EXPORT_END
 
+#if defined(_WIN32)
+/* process.c (Windows only): build/free the file descriptor inheritance
+ * snapshot passed to CreateProcessW via lpReserved2.  These are used by
+ * both process.c and io.c (pipe_open).  The full definition lives in
+ * win32/file.h, which is not pulled in here to keep this header portable. */
+struct rb_w32_inherit_actions;
+void rb_w32_build_inherit_actions(const struct rb_execarg *eargp,
+                                  struct rb_w32_inherit_actions *actions);
+void rb_w32_free_inherit_actions(struct rb_w32_inherit_actions *actions);
+#endif
+
 /* argv_str contains extra two elements.
  * The beginning one is for /bin/sh used by exec_with_sh.
  * The last one for terminating NULL used by execve.

io.c

@@ -276,6 +276,27 @@ rb_update_max_fd(int fd)
 void
 rb_maygvl_fd_fix_cloexec(int fd)
 {
+#ifdef _WIN32
+    /* Use the dedicated rb_w32_set_cloexec helper instead of the fcntl
+     * path below, so that both the OS-level HANDLE_FLAG_INHERIT bit and
+     * the CRT _osfile FNOINHERIT bit are kept in sync.  The standard
+     * handles (0, 1, 2) stay inheritable, while every other fd is made
+     * non-inheritable (close-on-exec) by default.  This matches the
+     * assumption elsewhere (notably the lpReserved2 fd-inheritance
+     * machinery) that a fd is inherited by a child only when
+     * close_on_exec was explicitly cleared. */
+    if (fd <= 2) {
+        if (rb_w32_set_cloexec(fd, FALSE) != 0)
+            rb_bug("rb_maygvl_fd_fix_cloexec: rb_w32_set_cloexec(%d, FALSE) failed: %s",
+                   fd, strerror(errno));
+    }
+    else {
+        if (rb_w32_set_cloexec(fd, TRUE) != 0)
+            rb_bug("rb_maygvl_fd_fix_cloexec: rb_w32_set_cloexec(%d, TRUE) failed: %s",
+                   fd, strerror(errno));
+    }
+    return;
+#endif
   /* MinGW don't have F_GETFD and FD_CLOEXEC.  [ruby-core:40281] */
 #if defined(HAVE_FCNTL) && defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
     int flags, flags2, ret;
@@ -303,6 +324,13 @@ rb_fd_fix_cloexec(int fd)
     rb_update_max_fd(fd);
 }
 
+/* License: Ruby's */
+int
+rb_get_max_fd(void)
+{
+    return (int)max_file_descriptor;
+}
+
 /* this is only called once */
 static int
 rb_fix_detect_o_cloexec(int fd)
@@ -7705,18 +7733,35 @@ pipe_open(VALUE execarg_obj, const char *modestr, enum rb_io_mode fmode,
 #   if defined(HAVE_SPAWNVE)
         if (eargp->envp_str) envp = (char **)RSTRING_PTR(eargp->envp_str);
 #   endif
-        while ((pid = DO_SPAWN(cmd, args, envp)) < 0) {
-            /* exec failed */
-            switch (e = errno) {
-              case EAGAIN:
+#   if defined(_WIN32)
+            /* On Windows, spawn through the inherit-table path so that
+             * close_on_exec = false fds (and any explicit fd_dup2 redirects
+             * set up above) propagate to the child via lpReserved2. */
+            struct rb_w32_inherit_actions actions;
+            rb_w32_build_inherit_actions(eargp, &actions);
+            if (args) {
+                pid = rb_w32_uaspawn_inherit(P_NOWAIT,
+                                             cmd, args, 0, CP_UTF8, &actions);
+            }
+            else {
+                pid = rb_w32_uspawn_inherit(P_NOWAIT, cmd, NULL,
+                                            CP_UTF8, &actions);
+            }
+            rb_w32_free_inherit_actions(&actions);
+#   else
+            while ((pid = DO_SPAWN(cmd, args, envp)) < 0) {
+                /* exec failed */
+                switch (e = errno) {
+                  case EAGAIN:
 #   if EWOULDBLOCK != EAGAIN
-              case EWOULDBLOCK:
+                  case EWOULDBLOCK:
 #   endif
-                rb_thread_sleep(1);
-                continue;
+                    rb_thread_sleep(1);
+                    continue;
+                }
+                break;
             }
-            break;
-        }
+#   endif
         if (eargp)
             rb_execarg_run_options(sargp, NULL, NULL, 0);
 # endif
@@ -7738,9 +7783,7 @@ pipe_open(VALUE execarg_obj, const char *modestr, enum rb_io_mode fmode,
 
     /* parent */
     if (pid < 0) {
-# if defined(HAVE_WORKING_FORK)
         e = errno;
-# endif
         close(arg.pair[0]);
         close(arg.pair[1]);
         if ((fmode & (FMODE_READABLE|FMODE_WRITABLE)) == (FMODE_READABLE|FMODE_WRITABLE)) {