AC_PREREQ(2.59)
AC_INIT(sandbox, 1.2.2, dev-portage@gentoo.org)
AM_INIT_AUTOMAKE
AC_CONFIG_HEADER([config.h])

# Checks for programs.
AC_PROG_CC
AC_ISC_POSIX
AC_PROG_INSTALL
AC_PROG_MAKE_SET
AC_PROG_AWK

AC_ENABLE_SHARED
AC_DISABLE_STATIC
# Next four lines is a hack to prevent libtool checking for CXX/F77
m4_undefine([AC_PROG_CXX])
m4_defun([AC_PROG_CXX],[])
m4_undefine([AC_PROG_F77])
m4_defun([AC_PROG_F77],[])
AC_PROG_LIBTOOL

AC_PREFIX_DEFAULT([/usr])

# Checks for libraries.
# Checks for header files.
AC_FUNC_ALLOCA
AC_HEADER_DIRENT
AC_HEADER_STDC
AC_HEADER_SYS_WAIT
AC_CHECK_HEADERS([ \
fcntl.h limits.h memory.h stddef.h \
stdlib.h string.h strings.h sys/file.h \
sys/param.h sys/time.h unistd.h utime.h \
])

# Checks for typedefs, structures, and compiler characteristics.
AC_C_CONST
AC_TYPE_UID_T
AC_TYPE_MODE_T
AC_TYPE_SIZE_T
AC_CHECK_TYPES([ptrdiff_t])

# Checks for library functions.
AC_FUNC_CHOWN
AC_FUNC_FORK
AC_FUNC_LSTAT
AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK
AC_FUNC_MALLOC
AC_FUNC_REALLOC
AC_TYPE_SIGNAL
AC_FUNC_STAT
AC_CHECK_FUNCS([ \
bzero ftruncate getcwd lchown memmove \
mempcpy memset mkdir pathconf realpath \
rmdir setenv strcasecmp strchr strdup \
strerror strndup strrchr strspn strstr \
])

dnl when using libc5, (f)trucate's offset argument type is size_t with
dnl libc5, but it's off_t with libc6 (glibc2).
AC_MSG_CHECKING(truncate argument type)
if echo '#include <unistd.h>' | $CC -E - | grep -q 'truncate.*size_t' ; then
	AC_MSG_RESULT(size_t)
	AC_DEFINE(TRUNCATE_T, size_t, [truncate arg type])
else
	AC_MSG_RESULT(off_t)
	AC_DEFINE(TRUNCATE_T, off_t, [truncate arg type])
fi

dnl we need to handle symbols differently based upon their version, 
dnl but we have to know which symbols the libc supports first
AC_MSG_CHECKING(libc path)
echo "int main(void) { return 0; }" > libctest.c
$CC -Wall -o libctest libctest.c
LIBC_PATH=`$CC $CFLAGS -Wl,-verbose -o libctest libctest.c 2>&1 | \
	$AWK '/attempt to open/ { if (($4 ~ /libc\.so/) && ($5 == "succeeded")) LIBC = $4; }; END {print LIBC}'`
if test "$LIBC_PATH"x = x ; then
	AC_MSG_ERROR(Unable to determine LIBC PATH)
fi
AC_MSG_RESULT($LIBC_PATH)
AC_SUBST(LIBC_PATH)

dnl when intercepting libc calls, we have to know the name of the 
dnl libc to load and search with dl*() calls
AC_MSG_CHECKING(libc version)
dnl the sed script at the end here looks funny but it's ok ...
dnl they're m4 escape sequences for left and right brackets
LIBC_VERSION=`readelf -d libctest | grep NEEDED.*libc\\.so | $AWK '{print $NF}' | sed -e 's:\@<:@::' -e 's:\@:>@::'`
if test "$LIBC_VERSION"x = x ; then
	AC_MSG_ERROR(Unable to determine LIBC VERSION)
fi
AC_MSG_RESULT($LIBC_VERSION)
AC_DEFINE_UNQUOTED(LIBC_VERSION, "$LIBC_VERSION", [name of libc to hook into])
rm -f libctest

AC_OUTPUT([Makefile])