[Python-checkins] cpython (merge 3.5 -> default): Issue #23735: Merge Readline resize handling from 3.5

[martin.panter]

https://hg.python.org/cpython/rev/41c2f8742bfe
changeset:   100841:41c2f8742bfe
parent:      100839:92947704321c
parent:      100840:b29edd0108ee
user:        Martin Panter <vadmium+py at gmail.com>
date:        Sun Apr 03 03:19:27 2016 +0000
summary:
  Issue #23735: Merge Readline resize handling from 3.5

files:
  Misc/ACKS          |   1 +
  Misc/NEWS          |   3 ++
  Modules/readline.c |  31 +++++++++++++++++++++++
  configure          |  44 ++++++++++++++++++++++++++++++++++
  configure.ac       |   5 +++
  pyconfig.h.in      |   3 ++
  6 files changed, 87 insertions(+), 0 deletions(-)


diff --git a/Misc/ACKS b/Misc/ACKS
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1160,6 +1160,7 @@
 Amrit Prem
 Paul Prescod
 Donovan Preston
+Eric Price
 Paul Price
 Iuliia Proskurnia
 Dorian Pula
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -237,6 +237,9 @@
 Library
 -------
 
+- Issue #23735: Handle terminal resizing with Readline 6.3+ by installing our
+  own SIGWINCH handler.  Patch by Eric Price.
+
 - Issue #25951: Change SSLSocket.sendall() to return None, as explicitly
   documented for plain socket objects.  Patch by Aviv Palivoda.
 
diff --git a/Modules/readline.c b/Modules/readline.c
--- a/Modules/readline.c
+++ b/Modules/readline.c
@@ -926,6 +926,26 @@
 
 #endif
 
+#ifdef HAVE_RL_RESIZE_TERMINAL
+static volatile sig_atomic_t sigwinch_received;
+static sighandler_t sigwinch_ohandler;
+
+static void
+readline_sigwinch_handler(int signum)
+{
+    sigwinch_received = 1;
+    if (sigwinch_ohandler &&
+            sigwinch_ohandler != SIG_IGN && sigwinch_ohandler != SIG_DFL)
+        sigwinch_ohandler(signum);
+
+#ifndef HAVE_SIGACTION
+    /* If the handler was installed with signal() rather than sigaction(),
+    we need to reinstall it. */
+    PyOS_setsig(SIGWINCH, readline_sigwinch_handler);
+#endif
+}
+#endif
+
 /* C function to call the Python completer. */
 
 static char *
@@ -1031,6 +1051,10 @@
     /* Bind both ESC-TAB and ESC-ESC to the completion function */
     rl_bind_key_in_map ('\t', rl_complete, emacs_meta_keymap);
     rl_bind_key_in_map ('\033', rl_complete, emacs_meta_keymap);
+#ifdef HAVE_RL_RESIZE_TERMINAL
+    /* Set up signal handler for window resize */
+    sigwinch_ohandler = PyOS_setsig(SIGWINCH, readline_sigwinch_handler);
+#endif
     /* Set our hook functions */
     rl_startup_hook = on_startup_hook;
 #ifdef HAVE_RL_PRE_INPUT_HOOK
@@ -1116,6 +1140,13 @@
             struct timeval *timeoutp = NULL;
             if (PyOS_InputHook)
                 timeoutp = &timeout;
+#ifdef HAVE_RL_RESIZE_TERMINAL
+            /* Update readline's view of the window size after SIGWINCH */
+            if (sigwinch_received) {
+                sigwinch_received = 0;
+                rl_resize_terminal();
+            }
+#endif
             FD_SET(fileno(rl_instream), &selectset);
             /* select resets selectset if no input was available */
             has_input = select(fileno(rl_instream) + 1, &selectset,
diff --git a/configure b/configure
--- a/configure
+++ b/configure
@@ -14929,6 +14929,50 @@
 fi
 
 
+# also in 4.0, but not in editline
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for rl_resize_terminal in -lreadline" >&5
+$as_echo_n "checking for rl_resize_terminal in -lreadline... " >&6; }
+if ${ac_cv_lib_readline_rl_resize_terminal+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lreadline $READLINE_LIBS $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char rl_resize_terminal ();
+int
+main ()
+{
+return rl_resize_terminal ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_readline_rl_resize_terminal=yes
+else
+  ac_cv_lib_readline_rl_resize_terminal=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_readline_rl_resize_terminal" >&5
+$as_echo "$ac_cv_lib_readline_rl_resize_terminal" >&6; }
+if test "x$ac_cv_lib_readline_rl_resize_terminal" = xyes; then :
+
+$as_echo "#define HAVE_RL_RESIZE_TERMINAL 1" >>confdefs.h
+
+fi
+
+
 # check for readline 4.2
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for rl_completion_matches in -lreadline" >&5
 $as_echo_n "checking for rl_completion_matches in -lreadline... " >&6; }
diff --git a/configure.ac b/configure.ac
--- a/configure.ac
+++ b/configure.ac
@@ -4527,6 +4527,11 @@
 	AC_DEFINE(HAVE_RL_COMPLETION_DISPLAY_MATCHES_HOOK, 1,
         [Define if you have readline 4.0]), ,$READLINE_LIBS)
 
+# also in 4.0, but not in editline
+AC_CHECK_LIB(readline, rl_resize_terminal,
+	AC_DEFINE(HAVE_RL_RESIZE_TERMINAL, 1,
+        [Define if you have readline 4.0]), ,$READLINE_LIBS)
+
 # check for readline 4.2
 AC_CHECK_LIB(readline, rl_completion_matches,
 	AC_DEFINE(HAVE_RL_COMPLETION_MATCHES, 1,
diff --git a/pyconfig.h.in b/pyconfig.h.in
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -735,6 +735,9 @@
 /* Define if you have readline 4.0 */
 #undef HAVE_RL_PRE_INPUT_HOOK
 
+/* Define if you have readline 4.0 */
+#undef HAVE_RL_RESIZE_TERMINAL
+
 /* Define to 1 if you have the `round' function. */
 #undef HAVE_ROUND
 

-- 
Repository URL: https://hg.python.org/cpython