From: Soeren Apel <redacted>
Date: Sun, 26 Jul 2020 15:11:37 +0000 (+0200)
Subject: configure: Add optional TI-RPC dependency, unbreak VXI communication.
X-Git-Url: http://sigrok.org/gitweb/?p=libsigrok.git;a=commitdiff_plain;h=a3fe36d01ef4ec7c70c0fda7911ff6710116cee6

configure: Add optional TI-RPC dependency, unbreak VXI communication.

Recent glibc-2.26 no longer provides support for SunRPC, and libsigrok's
build support failed to detect the presence of libtirpc in that case.

  https://wiki.gentoo.org/wiki/Glibc_2.26_porting_notes/RPC_implementation

Extend the check, use either SunRPC or TI-RPC. Which re-enables VXI on
recent setups. This resolves bug #1473.
---

diff --git a/Makefile.am b/Makefile.am
index 88bf1eb9..bdd3c61b 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -27,7 +27,7 @@ DISTCHECK_CONFIGURE_FLAGS = --disable-python
 
 FIRMWARE_DIR = $(datadir)/sigrok-firmware
 
-local_includes = -Iinclude -I$(srcdir)/include -I$(srcdir)/src -I.
+local_includes = -Iinclude -I$(srcdir)/include -I$(srcdir)/src -I. @RPC_CFLAGS@
 if BINDINGS_CXX
 local_includes += -Ibindings/cxx/include -I$(srcdir)/bindings/cxx/include -Ibindings/cxx
 endif
diff --git a/README b/README
index c8141dc1..5ab36116 100644
--- a/README
+++ b/README
@@ -38,6 +38,7 @@ Requirements for the C library:
  - pkg-config >= 0.22
  - libglib >= 2.32.0
  - libzip >= 0.10
+ - libtirpc (optional, used by VXI, fallback when glibc >= 2.26)
  - libserialport >= 0.1.1 (optional, used by some drivers)
  - librevisa >= 0.0.20130412 (optional, used by some drivers)
  - libusb-1.0 >= 1.0.16 (optional, used by some drivers)
diff --git a/configure.ac b/configure.ac
index ee3481c4..2f8c2c36 100644
--- a/configure.ac
+++ b/configure.ac
@@ -188,13 +188,25 @@ AS_CASE([$host_os], [mingw*], [SR_PREPEND([SR_EXTRA_LIBS], [-lws2_32])])
 SR_SEARCH_LIBS([SR_EXTRA_LIBS], [pow], [m])
 
 # RPC is only needed for VXI support.
-AC_CACHE_CHECK([for RPC support], [sr_cv_have_rpc],
+AC_CACHE_CHECK([for SunRPC support], [sr_cv_have_sunrpc],
 	[AC_LINK_IFELSE([AC_LANG_PROGRAM(
 			[[#include <rpc/rpc.h>]m4_newline[CLIENT *rpc_test(void);]],
 			[[(void) clnt_create("", 0, 0, "");]])],
-		[sr_cv_have_rpc=yes], [sr_cv_have_rpc=no])])
+		[RPC_CFLAGS=""; RPC_LIBS=""; sr_cv_have_sunrpc=yes],
+		[sr_cv_have_sunrpc=no])])
+PKG_CHECK_MODULES([TIRPC],
+	[libtirpc],
+	[RPC_CFLAGS=$TIRPC_CFLAGS; SR_PREPEND([SR_EXTRA_LIBS], [$TIRPC_LIBS]); sr_cv_have_tirpc=yes],
+	[sr_cv_have_tirpc=no])
+AS_IF([test "x$sr_cv_have_sunrpc" = xyes -o "x$sr_cv_have_tirpc" = xyes],
+	[sr_cv_have_rpc=yes], [sr_cv_have_rpc=no])
+
+AC_SUBST(RPC_CFLAGS)
+AC_SUBST(RPC_LIBS)
+
 AS_IF([test "x$sr_cv_have_rpc" = xyes],
-	[AC_DEFINE([HAVE_RPC], [1], [Specifies whether we have RPC support.])])
+	[AC_DEFINE([HAVE_RPC], [1], [Specifies whether we have RPC support (either by SunRPC or libtirpc).])])
+
 # VXI support is only compiled if RPC support was found.
 AM_CONDITIONAL([NEED_RPC], [test "x$sr_cv_have_rpc" = xyes])
 
@@ -643,6 +655,8 @@ Enabled serial communication transports:
 
 Enabled SCPI backends:
  - TCP............................. yes
+ - SunRPC ......................... $sr_cv_have_sunrpc
+ - TI-RPC ......................... $sr_cv_have_tirpc
  - RPC............................. $sr_cv_have_rpc
  - serial.......................... $sr_have_serial_comm
  - VISA............................ $sr_have_librevisa