1#!/usr/bin/m4
2#
3# Copyright (c) 2018 The strace developers.
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions
8# are met:
9# 1. Redistributions of source code must retain the above copyright
10#    notice, this list of conditions and the following disclaimer.
11# 2. Redistributions in binary form must reproduce the above copyright
12#    notice, this list of conditions and the following disclaimer in the
13#    documentation and/or other materials provided with the distribution.
14# 3. The name of the author may not be used to endorse or promote products
15#    derived from this software without specific prior written permission.
16#
17# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28AC_DEFUN([st_ARG_LIBDW], [dnl
29
30: ${libdw_CPPFLAGS=}
31: ${libdw_CFLAGS=}
32: ${libdw_LDFLAGS=}
33: ${libdw_LIBS=}
34
35AC_ARG_WITH([libdw],
36	    [AS_HELP_STRING([--with-libdw],
37			    [use libdw to implement stack tracing support]
38			   )
39	    ],
40	    [case "${withval}" in
41	     yes|no|check) ;;
42	     *) libdw_CPPFLAGS="-I${withval}/include"
43		libdw_LDFLAGS="-L${withval}/lib"
44		with_libdw=yes ;;
45	     esac
46	    ],
47	    [with_libdw=check]
48	   )
49
50])
51
52AC_DEFUN([st_LIBDW], [dnl
53
54have_libdw=
55
56AS_IF([test "x$with_libdw" != xno && test "x$use_unwinder" = x],
57      [saved_CPPFLAGS="$CPPFLAGS"
58       saved_CFLAGS="$CFLAGS"
59       CPPFLAGS="$CPPFLAGS $libdw_CPPFLAGS"
60       CFLAGS="$CFLAGS $libdw_CFLAGS"
61
62       AC_CHECK_HEADERS([elfutils/libdwfl.h],
63			[AC_CHECK_LIB([dw], [dwfl_linux_proc_attach],
64				      [libdw_LIBS="-ldw $libdw_LIBS"
65				       AC_CACHE_CHECK([for elfutils version],
66						      [st_cv_ELFUTILS_VERSION],
67						      [[st_cv_ELFUTILS_VERSION="$(echo _ELFUTILS_VERSION |
68										  $CPP $CPPFLAGS -P -imacros elfutils/version.h - |
69										  grep '^[0-9]')"
70							test -n "$st_cv_ELFUTILS_VERSION" ||
71								st_cv_ELFUTILS_VERSION=0
72						      ]]
73						     )
74				       AS_IF([test "$st_cv_ELFUTILS_VERSION" -ge 164],
75					     [have_libdw=yes],
76					     [AS_IF([test "x$with_libdw" = xyes],
77						    [AC_MSG_ERROR([elfutils version >= 164 is required for stack tracing support])],
78						    [AC_MSG_WARN([elfutils version >= 164 is required for stack tracing support])]
79						   )
80					     ]
81					    )
82				      ],
83				      [AS_IF([test "x$with_libdw" = xyes],
84					     [AC_MSG_FAILURE([failed to find dwfl_linux_proc_attach in libdw])],
85					    )
86				      ],
87				      [$libdw_LDFLAGS $libdw_LIBS]
88				     )
89			],
90			[AS_IF([test "x$with_libdw" = xyes],
91			       [AC_MSG_FAILURE([failed to find elfutils/libdwfl.h])]
92			      )
93			]
94		       )
95
96       CFLAGS="$saved_CFLAGS"
97       CPPFLAGS="$saved_CPPFLAGS"
98      ]
99)
100
101AS_IF([test "x$have_libdw" = xyes],
102      [use_unwinder=libdw
103       AC_DEFINE([USE_LIBDW], 1,
104		 [Whether to use libdw for stack tracing]
105		)
106       AC_SUBST(libdw_CPPFLAGS)
107       AC_SUBST(libdw_CFLAGS)
108       AC_SUBST(libdw_LDFLAGS)
109       AC_SUBST(libdw_LIBS)
110      ]
111     )
112
113])
114