From f409ee343fe6cdc059bb411746f27a515aec66a8 Mon Sep 17 00:00:00 2001 From: Jan Tojnar Date: Sat, 24 Dec 2022 16:46:18 +0100 Subject: [PATCH 2/4] libbacktrace: Allow configuring debug dir MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On platforms that do not use FHS like NixOS or GNU Guix, the build-id directories are not under `/usr/lib/debug`. Let’s add `--with-separate-debug-dir` configure flag so that the path can be changed. The same flag is supported by gdb: https://github.com/bminor/binutils-gdb/blob/095f84c7e3cf85cd68c657c46b80be078f336bc9/gdb/configure.ac#L113-L115 --- Makefile.am | 11 ++++++----- configure.ac | 8 ++++++++ elf.c | 4 ++-- 3 files changed, 16 insertions(+), 7 deletions(-) diff --git a/Makefile.am b/Makefile.am index 6eab991..da443c1 100644 --- a/Makefile.am +++ b/Makefile.am @@ -33,7 +33,8 @@ ACLOCAL_AMFLAGS = -I config AM_CPPFLAGS = -AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) +AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) \ + -DSYSTEM_DEBUG_DIR=\"$(SEPARATE_DEBUG_DIR)\" include_HEADERS = backtrace.h backtrace-supported.h @@ -134,7 +135,7 @@ 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/ +TEST_DEBUG_DIR=$(abs_builddir)/usr/lib/debug check_LTLIBRARIES += libbacktrace_elf_for_test.la @@ -143,8 +144,8 @@ 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.*$$'; \ - REPLACE="#define SYSTEM_BUILD_ID_DIR \"$(TEST_BUILD_ID_DIR)\""; \ + SEARCH='^#define BUILD_ID_DIR.*$$'; \ + REPLACE='\0\n#undef SYSTEM_DEBUG_DIR\n#define SYSTEM_DEBUG_DIR "$(TEST_DEBUG_DIR)"'; \ $(SED) "s%$$SEARCH%$$REPLACE%" \ $< \ > $@.tmp @@ -468,7 +469,7 @@ endif HAVE_OBJCOPY_DEBUGLINK %_buildid: % ./install-debuginfo-for-buildid.sh \ - "$(TEST_BUILD_ID_DIR)" \ + "$(TEST_DEBUG_DIR)/.build-id" \ $< $(OBJCOPY) --strip-debug $< $@ diff --git a/configure.ac b/configure.ac index 7f122cb..bb590ab 100644 --- a/configure.ac +++ b/configure.ac @@ -67,6 +67,14 @@ AM_MAINTAINER_MODE AC_ARG_WITH(target-subdir, [ --with-target-subdir=SUBDIR Configuring in a subdirectory for target]) +AC_ARG_WITH(separate-debug-dir, +[ --with-separate-debug-dir=DEBUGDIR Look for global separate debug info in this path @<:@LIBDIR/debug@:>@], +[separate_debug_dir=$withval], +[separate_debug_dir=$libdir/debug]) + +SEPARATE_DEBUG_DIR=$separate_debug_dir +AC_SUBST(SEPARATE_DEBUG_DIR) + # We must force CC to /not/ be precious variables; otherwise # the wrong, non-multilib-adjusted value will be used in multilibs. # As a side effect, we have to subst CFLAGS ourselves. diff --git a/elf.c b/elf.c index e82ecc5..8b1189c 100644 --- a/elf.c +++ b/elf.c @@ -856,7 +856,7 @@ elf_readlink (struct backtrace_state *state, const char *filename, } } -#define SYSTEM_BUILD_ID_DIR "/usr/lib/debug/.build-id/" +#define BUILD_ID_DIR "/.build-id/" /* Open a separate debug info file, using the build ID to find it. Returns an open file descriptor, or -1. @@ -870,7 +870,7 @@ elf_open_debugfile_by_buildid (struct backtrace_state *state, backtrace_error_callback error_callback, void *data) { - const char * const prefix = SYSTEM_BUILD_ID_DIR; + const char * const prefix = SYSTEM_DEBUG_DIR BUILD_ID_DIR; const size_t prefix_len = strlen (prefix); const char * const suffix = ".debug"; const size_t suffix_len = strlen (suffix); -- 2.38.1