Make libelf support optional

configure.ac

@@ -145,7 +145,6 @@ PKG_CHECK_MODULES(APPSTREAM_GLIB, appstream-glib >= 0.5.10)
 PKG_CHECK_MODULES(GUSB, gusb >= 0.2.9)
 PKG_CHECK_MODULES(SQLITE, sqlite3)
 PKG_CHECK_MODULES(ARCHIVE, libarchive)
-PKG_CHECK_MODULES(ELF, libelf)
 PKG_CHECK_MODULES(SOUP, libsoup-2.4 >= 2.51.92)
 AC_PATH_PROG(DOCBOOK2MAN, docbook2man)
 if test -z $DOCBOOK2MAN ; then
@@ -177,6 +176,27 @@ else
 fi
 AM_CONDITIONAL(HAVE_COLORHUG, test x$has_colorhug = xyes)
 
+# libelf support
+AC_ARG_ENABLE(libelf,
+	      AS_HELP_STRING([--enable-libelf],
+			     [Enable libelf support [default=auto]]),,
+	      enable_libelf=maybe)
+if test x$enable_libelf != xno; then
+	PKG_CHECK_MODULES(LIBELF, libelf >= 1.2.12,
+			  has_libelf=yes,
+			  has_libelf=no)
+fi
+if test x$has_libelf = xyes; then
+	AC_DEFINE(HAVE_LIBELF,1,[Use libelf support])
+else
+	has_libelf=no
+	if test "x$enable_libelf" = "xyes"; then
+		AC_MSG_ERROR([libelf support requested but 'libelf' was not found])
+	fi
+fi
+AM_CONDITIONAL(HAVE_LIBELF, test x$has_libelf = xyes)
+
+
 # gpgme support
 AC_MSG_CHECKING([for gpgme])
 if ! test -x "/usr/bin/gpgme-config"; then
@@ -320,6 +340,7 @@ echo "
 	optional providers
 	------------------
 	Colorhug:                  $has_colorhug
+	libelf:                    $has_libelf
 	UEFI:                      $has_fwup
 	Dell:                      $has_dell
 "

libdfu/dfu-format-elf.c

@@ -24,8 +24,12 @@
 #include <fcntl.h>
 #include <gelf.h>
 #include <gio/gunixinputstream.h>
+
+#ifdef HAVE_LIBELF
 #include <libelf.h>
 #include <linux/memfd.h>
+#endif
+
 #include <string.h>
 #include <sys/syscall.h>
 
@@ -60,6 +64,7 @@ dfu_firmware_detect_elf (GBytes *bytes)
 	return DFU_FIRMWARE_FORMAT_ELF;
 }
 
+#ifdef HAVE_LIBELF
 static DfuElement *
 _get_element_from_section_name (Elf *e, const gchar *desired_name)
 {
@@ -144,6 +149,7 @@ dfu_format_elf_symbols_from_symtab (DfuFirmware *firmware, Elf *e)
 		}
 	}
 }
+#endif
 
 /**
  * dfu_firmware_from_elf: (skip)
@@ -162,6 +168,7 @@ dfu_firmware_from_elf (DfuFirmware *firmware,
 		       DfuFirmwareParseFlags flags,
 		       GError **error)
 {
+#ifdef HAVE_LIBELF
 	guint i;
 	guint sections_cnt = 0;
 	g_autoptr(Elf) e = NULL;
@@ -230,8 +237,16 @@ dfu_firmware_from_elf (DfuFirmware *firmware,
 
 	/* success */
 	return TRUE;
+#else
+	g_set_error_literal (error,
+			     DFU_ERROR,
+			     DFU_ERROR_INTERNAL,
+			     "compiled without libelf support");
+	return FALSE;
+#endif
 }
 
+#ifdef HAVE_LIBELF
 static int
 _memfd_create (const char *name, unsigned int flags)
 {
@@ -299,6 +314,7 @@ dfu_format_elf_pack_image (Elf *e, DfuImage *image, GError **error)
 	}
 	return dfu_format_elf_pack_element (e, element, error);
 }
+#endif
 
 /**
  * dfu_firmware_to_elf: (skip)
@@ -312,6 +328,7 @@ dfu_format_elf_pack_image (Elf *e, DfuImage *image, GError **error)
 GBytes *
 dfu_firmware_to_elf (DfuFirmware *firmware, GError **error)
 {
+#ifdef HAVE_LIBELF
 	DfuImage *image;
 	Elf32_Ehdr *ehdr;
 	Elf32_Shdr *shdr;
@@ -446,4 +463,11 @@ dfu_firmware_to_elf (DfuFirmware *firmware, GError **error)
 		return NULL;
 	}
 	return g_input_stream_read_bytes (stream, fsize, NULL, error);
+#else
+	g_set_error_literal (error,
+			     DFU_ERROR,
+			     DFU_ERROR_INTERNAL,
+			     "compiled without libelf support");
+	return FALSE;
+#endif
 }

libdfu/dfu-self-test.c

@@ -362,6 +362,11 @@ dfu_firmware_elf_func (void)
 	g_autoptr(GError) error = NULL;
 	g_autoptr(GFile) file = NULL;
 
+#ifndef HAVE_LIBELF
+	g_test_skip ("compiled without libelf support");
+	return;
+#endif
+
 	/* load a ELF firmware */
 	filename = dfu_test_get_filename ("example.elf");
 	g_assert (filename != NULL);