musl: Add musl compatibility

Thanks for hints Alpine Linux project and their patches:
https://git.alpinelinux.org/aports/tree/community/accel-ppp?h=master

We can adjust a bit code and cmake config files to make accel-ppp
buildable under musl "as is".

Signed-off-by: Denys Fedoryshchenko <denys.f@collabora.com>

5 files changed, 54 insertions, 1 deletions

diff --git a/accel-pppd/CMakeLists.txt b/accel-pppd/CMakeLists.txt
index ab8a3508..d194eaa7 100644
--- a/accel-pppd/CMakeLists.txt
+++ b/accel-pppd/CMakeLists.txt
@@ -44,6 +44,33 @@ IF (RADIUS)
 	ADD_SUBDIRECTORY(radius)
 ENDIF (RADIUS)
 
+# define __free_fn_t in musl
+INCLUDE (CheckCSourceCompiles)
+CHECK_C_SOURCE_COMPILES("
+#include <stdlib.h>
+int main(void)
+{
+	__free_fn_t *f;
+	return 0;
+}" HAVE_FREE_FN_T)
+IF (HAVE_FREE_FN_T)
+	ADD_DEFINITIONS(-DHAVE_FREE_FN_T)
+ENDIF (HAVE_FREE_FN_T)
+
+INCLUDE (CheckCSourceCompiles)
+CHECK_C_SOURCE_COMPILES("
+#include <linux/if_arp.h>
+#include <net/ethernet.h>
+int main(void)
+{
+	return 0;
+}" HAVE_GOOD_IFARP)
+
+IF (HAVE_GOOD_IFARP)
+	ADD_DEFINITIONS(-DHAVE_GOOD_IFARP)
+ENDIF (HAVE_GOOD_IFARP)
+
+
 ADD_SUBDIRECTORY(triton)
 ADD_SUBDIRECTORY(vlan-mon)
 ADD_SUBDIRECTORY(ctrl)
@@ -62,6 +89,12 @@ ENDIF (SHAPER)
 
 INCLUDE(CheckIncludeFile)
 CHECK_INCLUDE_FILE("linux/netfilter/ipset/ip_set.h" HAVE_IPSET)
+# MUSL does not have printf.h
+CHECK_INCLUDE_FILE("printf.h" HAVE_PRINTF_H)
+IF (HAVE_PRINTF_H)
+	ADD_DEFINITIONS(-DHAVE_PRINTF_H)
+ENDIF (HAVE_PRINTF_H)
+
 
 INCLUDE(CheckFunctionExists)
 CHECK_FUNCTION_EXISTS(setns HAVE_SETNS)
@@ -123,7 +156,17 @@ ADD_EXECUTABLE(accel-pppd
 	main.c
 )
 
-TARGET_LINK_LIBRARIES(accel-pppd triton rt pthread ${crypto_lib} pcre)
+# check if we have getcontext/setcontext
+INCLUDE(CheckFunctionExists)
+CHECK_FUNCTION_EXISTS(getcontext HAVE_GETCONTEXT)
+CHECK_FUNCTION_EXISTS(setcontext HAVE_SETCONTEXT)
+
+IF (HAVE_GETCONTEXT AND HAVE_SETCONTEXT)
+	TARGET_LINK_LIBRARIES(accel-pppd triton rt pthread ${crypto_lib} pcre)
+ELSE (HAVE_GETCONTEXT AND HAVE_SETCONTEXT)
+	TARGET_LINK_LIBRARIES(accel-pppd triton rt pthread ${crypto_lib} pcre ucontext)
+ENDIF (HAVE_GETCONTEXT AND HAVE_SETCONTEXT)
+
 set_property(TARGET accel-pppd PROPERTY CMAKE_SKIP_BUILD_RPATH FALSE)
 set_property(TARGET accel-pppd PROPERTY CMAKE_BUILD_WITH_INSTALL_RPATH FALSE)
 set_property(TARGET accel-pppd PROPERTY INSTALL_RPATH_USE_LINK_PATH FALSE)
diff --git a/accel-pppd/ctrl/ipoe/arp.c b/accel-pppd/ctrl/ipoe/arp.c
index e9b55ff4..ef9d3859 100644
--- a/accel-pppd/ctrl/ipoe/arp.c
+++ b/accel-pppd/ctrl/ipoe/arp.c
@@ -13,7 +13,9 @@
 #include <netinet/ip.h>
 #include <sys/socket.h>
 #include <sys/ioctl.h>
+#ifdef HAVE_GOOD_IFARP
 #include <linux/if_arp.h>
+#endif
 #include <linux/if_packet.h>
 
 #include "list.h"
diff --git a/accel-pppd/ctrl/ipoe/ipoe.c b/accel-pppd/ctrl/ipoe/ipoe.c
index 61b7c238..95ff8568 100644
--- a/accel-pppd/ctrl/ipoe/ipoe.c
+++ b/accel-pppd/ctrl/ipoe/ipoe.c
@@ -15,7 +15,9 @@
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <linux/if.h>
+#ifdef HAVE_GOOD_IFARP
 #include <linux/if_arp.h>
+#endif
 #include <linux/route.h>
 
 #include <pcre.h>
diff --git a/accel-pppd/ctrl/l2tp/l2tp.c b/accel-pppd/ctrl/l2tp/l2tp.c
index 027d7100..9fc2283c 100644
--- a/accel-pppd/ctrl/l2tp/l2tp.c
+++ b/accel-pppd/ctrl/l2tp/l2tp.c
@@ -853,7 +853,11 @@ static void l2tp_tunnel_free_sessions(struct l2tp_conn_t *conn)
 	void *sessions = conn->sessions;
 
 	conn->sessions = NULL;
+#ifdef HAVE_FREE_FN_T
 	tdestroy(sessions, (__free_fn_t)l2tp_session_free);
+#else
+	tdestroy(sessions, free);
+#endif
 	/* Let l2tp_session_free() handle the session counter and
 	 * the reference held by the tunnel.
 	 */
diff --git a/accel-pppd/ctrl/pppoe/pppoe.c b/accel-pppd/ctrl/pppoe/pppoe.c
index 76684285..dd623acc 100644
--- a/accel-pppd/ctrl/pppoe/pppoe.c
+++ b/accel-pppd/ctrl/pppoe/pppoe.c
@@ -11,7 +11,9 @@
 #include <net/ethernet.h>
 #include <netpacket/packet.h>
 #include <arpa/inet.h>
+#ifdef HAVE_PRINTF_H
 #include <printf.h>
+#endif
 
 #include "crypto.h"