From 0bd1b82d3a7901db924b9d81181196a3673391ca Mon Sep 17 00:00:00 2001
From: Andrew Wood <ivarch657@gmail.com>
Date: Mon, 28 Aug 2023 17:44:53 +0100
Subject: [PATCH] Move libgen.h out of IPC conditional code since it is not
 related directly to IPC; adjust IPC configuration so that IPC support is
 auto-disabled if the relevant header files or library functions are missing.

---
 Makefile.am              |  2 +-
 configure.ac             | 12 +++++++++++-
 src/include/config-aux.h |  5 -----
 src/include/config.h.in  |  9 +++++++++
 src/pv/cursor.c          |  4 +++-
 5 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index fd95255..594efbb 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,6 @@
 ## Process this file with automake to produce Makefile.in
 
-AUTOMAKE_OPTIONS = subdir-objects no-dependencies
+AUTOMAKE_OPTIONS = subdir-objects
 
 SUBDIRS = po
 
diff --git a/configure.ac b/configure.ac
index 2201a15..6b4e96a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -24,6 +24,7 @@ AC_CHECK_FUNCS([fpathconf sysconf posix_memalign posix_fadvise])
 AC_CHECK_HEADERS([limits.h])
 AC_CHECK_HEADERS([wctype.h])
 AC_CHECK_HEADERS([termios.h])
+AC_CHECK_HEADERS([libgen.h])
 AC_CHECK_HEADERS([sys/ioctl.h])
 AC_CHECK_HEADERS([libintl.h locale.h])
 AH_BOTTOM([#include "config-aux.h"])
@@ -78,7 +79,16 @@ yes
 ], [LIBS="$LIBS -lc128"])
 
 if test "$IPC_SUPPORT" = "yes"; then
-  AC_CHECK_HEADERS([sys/ipc.h sys/param.h libgen.h])
+  AC_CHECK_HEADERS([sys/ipc.h], [], [IPC_SUPPORT=no])
+  AC_CHECK_HEADERS([sys/msg.h], [], [IPC_SUPPORT=no])
+  AC_CHECK_HEADERS([sys/param.h])
+  if test "$IPC_SUPPORT" = "yes"; then
+    AC_CHECK_FUNCS([msgget], [], [IPC_SUPPORT=no])
+  fi
+fi
+
+if test "$IPC_SUPPORT" = "yes"; then
+  AC_DEFINE([HAVE_IPC], [1], [IPC support enabled])
 fi
 
 if test "$SPLICE_SUPPORT" = "yes"; then
diff --git a/src/include/config-aux.h b/src/include/config-aux.h
index 1971c42..96b9763 100644
--- a/src/include/config-aux.h
+++ b/src/include/config-aux.h
@@ -22,11 +22,6 @@
 # define N_(String) (String)
 #endif
 
-#undef HAVE_IPC
-#ifdef HAVE_SYS_IPC_H
-#define HAVE_IPC 1
-#endif
-
 #undef CURSOR_ANSWERBACK_BYTE_BY_BYTE
 #ifndef _AIX
 #define CURSOR_ANSWERBACK_BYTE_BY_BYTE 1
diff --git a/src/include/config.h.in b/src/include/config.h.in
index d7b8f2c..112b538 100644
--- a/src/include/config.h.in
+++ b/src/include/config.h.in
@@ -43,6 +43,9 @@
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
+/* IPC support enabled */
+#undef HAVE_IPC
+
 /* Define to 1 if you have the <libgen.h> header file. */
 #undef HAVE_LIBGEN_H
 
@@ -61,6 +64,9 @@
 /* Define to 1 if you have the <minix/config.h> header file. */
 #undef HAVE_MINIX_CONFIG_H
 
+/* Define to 1 if you have the `msgget' function. */
+#undef HAVE_MSGGET
+
 /* Define to 1 if you have the `posix_fadvise' function. */
 #undef HAVE_POSIX_FADVISE
 
@@ -100,6 +106,9 @@
 /* Define to 1 if you have the <sys/ipc.h> header file. */
 #undef HAVE_SYS_IPC_H
 
+/* Define to 1 if you have the <sys/msg.h> header file. */
+#undef HAVE_SYS_MSG_H
+
 /* Define to 1 if you have the <sys/param.h> header file. */
 #undef HAVE_SYS_PARAM_H
 
diff --git a/src/pv/cursor.c b/src/pv/cursor.c
index 6d0e3a2..84f2a13 100644
--- a/src/pv/cursor.c
+++ b/src/pv/cursor.c
@@ -35,10 +35,12 @@
 #ifdef HAVE_SYS_PARAM_H
 #include <sys/param.h>
 #endif
+#endif				/* HAVE_IPC */
+
+/* for basename() */
 #ifdef HAVE_LIBGEN_H
 #include <libgen.h>
 #endif
-#endif				/* HAVE_IPC */
 
 
 /*