[libbacktrace] Add test-cases exercising build-id and dwz

Add test-cases b2test_buildid and b3test_dwz_buildid.

The last one triggers the segfault fixed by "[backtrace] Avoid segfault"
( r268275 ).

2019-01-29  Tom de Vries  <tdevries@suse.de>

	* install-debuginfo-for-buildid.sh.in: New script.
	* Makefile.am (check_PROGRAMS): Add b2test and b3test.
	(TESTS): Add b2test_buildid and b3test_dwz_buildid.
	* Makefile.in: Regenerate.
	* configure.ac (HAVE_ELF): Set with AM_CONDITIONAL.
	(READELF): Set with AC_CHECK_PROG.
	(install-debuginfo-for-buildid.sh): Generate with AC_CONFIG_FILES.
	* configure: Regenerate.
	* elf.c (SYSTEM_BUILD_ID_DIR): Factor out of ...
	(elf_open_debugfile_by_buildid): ... here.

From-SVN: r268369

libbacktrace/ChangeLog

 2019-01-29  Tom de Vries  <tdevries@suse.de>
 
+	* install-debuginfo-for-buildid.sh.in: New script.
+	* Makefile.am (check_PROGRAMS): Add b2test and b3test.
+	(TESTS): Add b2test_buildid and b3test_dwz_buildid.
+	* Makefile.in: Regenerate.
+	* configure.ac (HAVE_ELF): Set with AM_CONDITIONAL.
+	(READELF): Set with AC_CHECK_PROG.
+	(install-debuginfo-for-buildid.sh): Generate with AC_CONFIG_FILES.
+	* configure: Regenerate.
+	* elf.c (SYSTEM_BUILD_ID_DIR): Factor out of ...
+	(elf_open_debugfile_by_buildid): ... here.
+
+2019-01-29  Tom de Vries  <tdevries@suse.de>
+
 	* Makefile.am: Replace check_PROGRAMS with BUILDTESTS, except for
 	allocfail.
 	(TESTS): Don't add check_PROGRAMS. Add BUILDTESTS.

libbacktrace/Makefile.am

@@ -108,6 +108,28 @@ libbacktrace_noformat_la_LIBADD = $(BACKTRACE_FILE) $(VIEW_FILE) $(ALLOC_FILE)
 
 libbacktrace_noformat_la_DEPENDENCIES = $(libbacktrace_noformat_la_LIBADD)
 
+if HAVE_ELF
+if HAVE_OBJCOPY_DEBUGLINK
+
+TEST_BUILD_ID_DIR=$(abs_builddir)/usr/lib/debug/.build-id/
+
+check_LTLIBRARIES += libbacktrace_elf_for_test.la
+
+libbacktrace_elf_for_test_la_SOURCES = $(libbacktrace_la_SOURCES)
+libbacktrace_elf_for_test_la_LIBADD = $(BACKTRACE_FILE) elf_for_test.lo \
+	$(VIEW_FILE) $(ALLOC_FILE)
+
+elf_for_test.c: elf.c
+	SEARCH='^#define SYSTEM_BUILD_ID_DIR.*$$'; \
+	REPLACE="#define SYSTEM_BUILD_ID_DIR \"$(TEST_BUILD_ID_DIR)\""; \
+	$(SED) "s%$$SEARCH%$$REPLACE%" \
+		$< \
+		> $@.tmp
+	mv $@.tmp $@
+
+endif HAVE_OBJCOPY_DEBUGLINK
+endif HAVE_ELF
+
 xcoff_%.c: xcoff.c
 	SEARCH='#error "Unknown BACKTRACE_XCOFF_SIZE"'; \
 	REPLACE='#undef BACKTRACE_XCOFF_SIZE\
@@ -172,6 +194,28 @@ allocfail.sh: allocfail
 
 TESTS += allocfail.sh
 
+if HAVE_ELF
+if HAVE_OBJCOPY_DEBUGLINK
+
+b2test_SOURCES = $(btest_SOURCES)
+b2test_CFLAGS = $(btest_CFLAGS)
+b2test_LDFLAGS = -Wl,--build-id
+b2test_LDADD = libbacktrace_elf_for_test.la
+
+check_PROGRAMS += b2test
+TESTS += b2test_buildid
+
+b3test_SOURCES = $(btest_SOURCES)
+b3test_CFLAGS = $(btest_CFLAGS)
+b3test_LDFLAGS = -Wl,--build-id
+b3test_LDADD = libbacktrace_elf_for_test.la
+
+check_PROGRAMS += b3test
+TESTS += b3test_dwz_buildid
+
+endif HAVE_OBJCOPY_DEBUGLINK
+endif HAVE_ELF
+
 btest_SOURCES = btest.c testlib.c
 btest_CFLAGS = $(AM_CFLAGS) -g -O
 btest_LDADD = libbacktrace.la
@@ -275,6 +319,12 @@ TESTS += btest_gnudebuglink
 
 endif HAVE_OBJCOPY_DEBUGLINK
 
+%_buildid: %
+	./install-debuginfo-for-buildid.sh \
+	  "$(TEST_BUILD_ID_DIR)" \
+	  $<
+	$(OBJCOPY) --strip-debug $< $@
+
 if HAVE_COMPRESSED_DEBUG
 
 ctestg_SOURCES = btest.c testlib.c

libbacktrace/configure

@@ -637,6 +637,7 @@ NATIVE_FALSE
 NATIVE_TRUE
 HAVE_OBJCOPY_DEBUGLINK_FALSE
 HAVE_OBJCOPY_DEBUGLINK_TRUE
+READELF
 OBJCOPY
 HAVE_COMPRESSED_DEBUG_FALSE
 HAVE_COMPRESSED_DEBUG_TRUE
@@ -651,6 +652,8 @@ ALLOC_FILE
 VIEW_FILE
 BACKTRACE_SUPPORTS_DATA
 BACKTRACE_SUPPORTED
+HAVE_ELF_FALSE
+HAVE_ELF_TRUE
 FORMAT_FILE
 BACKTRACE_SUPPORTS_THREADS
 PIC_FLAG
@@ -11489,7 +11492,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11492 "configure"
+#line 11495 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11595,7 +11598,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11598 "configure"
+#line 11601 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12512,6 +12515,14 @@ cat >>confdefs.h <<_ACEOF
 #define BACKTRACE_ELF_SIZE $elfsize
 _ACEOF
 
+ if test "$FORMAT_FILE" = "elf.lo"; then
+  HAVE_ELF_TRUE=
+  HAVE_ELF_FALSE='#'
+else
+  HAVE_ELF_TRUE='#'
+  HAVE_ELF_FALSE=
+fi
+
 
 # XCOFF defines.
 xcoffsize=
@@ -13400,6 +13411,43 @@ $as_echo "no" >&6; }
 fi
 
 
+# Extract the first word of "readelf", so it can be a program name with args.
+set dummy readelf; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_prog_READELF+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test -n "$READELF"; then
+  ac_cv_prog_READELF="$READELF" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+    ac_cv_prog_READELF="readelf"
+    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+READELF=$ac_cv_prog_READELF
+if test -n "$READELF"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $READELF" >&5
+$as_echo "$READELF" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether objcopy supports debuglink" >&5
 $as_echo_n "checking whether objcopy supports debuglink... " >&6; }
 if ${libbacktrace_cv_objcopy_debuglink+:} false; then :
@@ -13473,6 +13521,8 @@ fi
 
 ac_config_files="$ac_config_files Makefile backtrace-supported.h"
 
+ac_config_files="$ac_config_files install-debuginfo-for-buildid.sh"
+
 
 # We need multilib support, but only if configuring for the target.
 ac_config_commands="$ac_config_commands default"
@@ -13611,6 +13661,10 @@ if test -z "${HAVE_DWZ_TRUE}" && test -z "${HAVE_DWZ_FALSE}"; then
   as_fn_error $? "conditional \"HAVE_DWZ\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${HAVE_ELF_TRUE}" && test -z "${HAVE_ELF_FALSE}"; then
+  as_fn_error $? "conditional \"HAVE_ELF\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${HAVE_PTHREAD_TRUE}" && test -z "${HAVE_PTHREAD_FALSE}"; then
   as_fn_error $? "conditional \"HAVE_PTHREAD\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
@@ -14525,6 +14579,7 @@ do
     "gstdint.h") CONFIG_COMMANDS="$CONFIG_COMMANDS gstdint.h" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
     "backtrace-supported.h") CONFIG_FILES="$CONFIG_FILES backtrace-supported.h" ;;
+    "install-debuginfo-for-buildid.sh") CONFIG_FILES="$CONFIG_FILES install-debuginfo-for-buildid.sh" ;;
     "default") CONFIG_COMMANDS="$CONFIG_COMMANDS default" ;;
 
   *) as_fn_error $? "invalid argument: \`$ac_config_target'" "$LINENO" 5;;
@@ -16140,6 +16195,7 @@ else
 fi
 
  ;;
+    "install-debuginfo-for-buildid.sh":F) chmod +x install-debuginfo-for-buildid.sh ;;
     "default":C) if test -n "$CONFIG_FILES"; then
    if test -n "${with_target_subdir}"; then
      # Multilibs need MULTISUBDIR defined correctly in certain makefiles so

libbacktrace/configure.ac

@@ -259,6 +259,7 @@ elf64) elfsize=64 ;;
 *)     elfsize=unused
 esac
 AC_DEFINE_UNQUOTED([BACKTRACE_ELF_SIZE], [$elfsize], [ELF size: 32 or 64])
+AM_CONDITIONAL(HAVE_ELF, test "$FORMAT_FILE" = "elf.lo")
 
 # XCOFF defines.
 xcoffsize=
@@ -445,6 +446,7 @@ AM_CONDITIONAL(HAVE_COMPRESSED_DEBUG, test "$libgo_cv_ld_compress" = yes)
 
 AC_ARG_VAR(OBJCOPY, [location of objcopy])
 AC_CHECK_PROG(OBJCOPY, objcopy, objcopy,)
+AC_CHECK_PROG(READELF, readelf, readelf)
 AC_CACHE_CHECK([whether objcopy supports debuglink],
 [libbacktrace_cv_objcopy_debuglink],
 [if test -n "${with_target_subdir}"; then
@@ -472,6 +474,7 @@ else
 fi
 
 AC_CONFIG_FILES(Makefile backtrace-supported.h)
+AC_CONFIG_FILES(install-debuginfo-for-buildid.sh, chmod +x install-debuginfo-for-buildid.sh)
 
 # We need multilib support, but only if configuring for the target.
 AC_CONFIG_COMMANDS([default],

libbacktrace/elf.c

@@ -809,6 +809,8 @@ elf_readlink (struct backtrace_state *state, const char *filename,
     }
 }
 
+#define SYSTEM_BUILD_ID_DIR "/usr/lib/debug/.build-id/"
+
 /* Open a separate debug info file, using the build ID to find it.
    Returns an open file descriptor, or -1.
 
@@ -821,7 +823,7 @@ elf_open_debugfile_by_buildid (struct backtrace_state *state,
 			       backtrace_error_callback error_callback,
 			       void *data)
 {
-  const char * const prefix = "/usr/lib/debug/.build-id/";
+  const char * const prefix = SYSTEM_BUILD_ID_DIR;
   const size_t prefix_len = strlen (prefix);
   const char * const suffix = ".debug";
   const size_t suffix_len = strlen (suffix);

libbacktrace/install-debuginfo-for-buildid.sh.in

+#!/bin/sh
+
+# install-debug-info-for-buildid.sh -- Helper script for libbacktrace library
+# testing.
+# Copyright (C) 2019 Free Software Foundation, Inc.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+
+#     (1) Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+
+#     (2) Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+
+#     (3) The name of the author may not be used to
+#     endorse or promote products derived from this software without
+#     specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+# Extract build-id from src, and copy debug info of src to
+# $build_id_dir/aa/bb...zz.debug.
+
+set -e
+
+sed=@SED@
+awk=@AWK@
+grep=@GREP@
+objcopy=@OBJCOPY@
+readelf=@READELF@
+mkdir_p="@MKDIR_P@"
+
+build_id_dir="$1"
+src="$2"
+
+buildid=$($readelf -n $src \
+	      | $grep "Build ID" \
+	      | $awk '{print $3}')
+
+prefix=$(echo $buildid \
+	     | $sed 's/^\(.\{2\}\).*/\1/')
+
+remainder=$(echo $buildid \
+		| $sed 's/^.\{2\}//')
+
+dir=$build_id_dir/$prefix
+dst=$dir/$remainder.debug
+
+$mkdir_p $dir
+
+$objcopy --only-keep-debug $src $dst