github #64: Fix a build-time error when building against ncurses that hadn't been built with --enable-wgetch-events.

The --enable-wgetch-events codepath is experimental (according to
ncurses-6.2/INSTALL) and off by default (according to
ncurses-6.2/configure.in).  With that codepath disabled, the macro
KEY_EVENT is not provided, which (before this commit) manifested as a
build-time error:

    [  245s] gcc -c -I. -I../../Src -I../../Src -I../../Src/Zle -I.  -DHAVE_CONFIG_H -DMODULE -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables -fstack-clash-protection -Werror=return-type -flto=auto -g -fPIE -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 -I/usr/include/ncursesw -fPIC -o curses..o curses.c
    [  246s] In file included from curses.c:210:
    [  246s] curses_keys.h:93:15: error: 'KEY_EVENT' undeclared here (not in a function); did you mean 'KEY_RESET'?
    [  246s]    93 |     {"EVENT", KEY_EVENT},
    [  246s]       |               ^~~~~~~~~
    [  246s]       |               KEY_RESET

curses_keys.h is only used for setting the "kevent" output parameter of
'zcurses input' (and the associated $zcurses_keycodes special variable),
so there's no harm in just leaving KEY_EVENT out of it.  (That codepath
deals gracefully with numeric values that don't correspond to any of the
known compile-time values, as that can happen whenever the build- and
run-time versions of ncurses don't provide the same set of KEY_* macros,
with or without relation to that configure flag.)

Reported by Martin Liska.

2 files changed, 12 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 83f305356..8b5e11c63 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2020-08-28  Daniel Shahaf  <d.s@daniel.shahaf.name>
+
+	* github #64: Src/Modules/curses_keys.awk: Fix a build-time
+	error when building against ncurses that hadn't been built
+	with --enable-wgetch-events.  (Reported by Martin Liska.)
+
 2020-08-21  Oliver Kiddle  <opk@zsh.org>
 
 	* 47328: Doc/Zsh/metafaq.yo, Etc/CONTRIBUTORS: remove references
diff --git a/Src/Modules/curses_keys.awk b/Src/Modules/curses_keys.awk
index ffb182c35..25bd63c7e 100644
--- a/Src/Modules/curses_keys.awk
+++ b/Src/Modules/curses_keys.awk
@@ -12,8 +12,13 @@ BEGIN {nkeydefs = 0}
 
 END {
     printf("static const struct zcurses_namenumberpair keypad_names[] = {\n")
-    for (i = 0; i < 0 + nkeydefs; i++)
+    for (i = 0; i < 0 + nkeydefs; i++) {
+        if (name[i] == "EVENT")
+            printf("#ifdef KEY_EVENT\n")
         printf("    {\"%s\", KEY_%s},\n", name[i], name[i])
+        if (name[i] == "EVENT")
+            printf("#endif\n")
+    }
     printf("    {NULL, 0}\n")
     printf("};\n")
 }