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authorSalvatore Cro <salvatore.cro@st.com>2010-09-09 15:45:44 +0200
committerCarmelo Amoroso <carmelo.amoroso@st.com>2010-09-15 12:31:22 +0200
commit37eb913ed8c4798b736e678f4dbd9f4a91a68f74 (patch)
tree63fc2c1dbb887a043a7291c9c6215d2db7b5ba5a
parent7ac7be14eb4c8927fddffbe01fed74c605bf8597 (diff)
libubacktrace: Provide uClibc with backtrace functions
A new shared object, libubacktrace.so.0 is added to uClibc to provide backtrace functions to support application self-debugging. This set of functions requires to dynamically load libgcc_s.so so they need to call dlopen/dlsym that are provided by libdl. For this reason they cannot be included into libc.so.0 but are provided by a new library. User application that wants to use backtrace needs to be compiled with -fexceptions option and -rdynamic to get full symbols printed and must be linked against libubacktrace.so Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
-rw-r--r--Makefile.in8
-rw-r--r--Makerules7
-rw-r--r--Rules.mak9
-rw-r--r--extra/Configs/Config.in19
-rw-r--r--include/execinfo.h44
-rw-r--r--libubacktrace/Makefile14
-rw-r--r--libubacktrace/Makefile.in84
-rw-r--r--libubacktrace/backtrace.c19
-rw-r--r--libubacktrace/backtracesyms.c105
-rw-r--r--libubacktrace/backtracesymsfd.c116
-rw-r--r--libubacktrace/sysdeps/sh/Makefile.arch12
-rw-r--r--libubacktrace/sysdeps/sh/backtrace.c84
12 files changed, 517 insertions, 4 deletions
diff --git a/Makefile.in b/Makefile.in
index fe8e98398..348bc0c3f 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -48,6 +48,7 @@ include $(top_srcdir)libresolv/Makefile.in
include $(top_srcdir)libutil/Makefile.in
include $(top_srcdir)libpthread/Makefile.in
include $(top_srcdir)librt/Makefile.in
+include $(top_srcdir)libubacktrace/Makefile.in
include $(top_srcdir)extra/locale/Makefile.in
# last included to catch all the objects added by others (locales/threads)
@@ -272,6 +273,7 @@ HEADERS_RM-$(UCLIBC_HAS_GLIBC_CUSTOM_PRINTF) += printf.h
HEADERS_RM-$(UCLIBC_HAS_GLOB) += glob.h
HEADERS_RM-$(UCLIBC_HAS_GNU_ERROR) += error.h
HEADERS_RM-$(UCLIBC_HAS_IPV6) += netinet/ip6.h netinet/icmp6.h
+HEADERS_RM-$(UCLIBC_HAS_BACKTRACE) += execinfo.h
HEADERS_RM-$(UCLIBC_HAS_LOCALE) += iconv.h
HEADERS_RM-$(UCLIBC_HAS_PTY) += pty.h
HEADERS_RM-$(UCLIBC_HAS_REGEX) += regex.h regexp.h
@@ -330,6 +332,12 @@ ifeq ($(HARDWIRED_ABSPATH),y)
else
-$(INSTALL) -m 755 $(top_builddir)lib/libc.so $(PREFIX)$(DEVEL_PREFIX)$(MULTILIB_DIR)/
endif
+ifeq ($(UCLIBC_HAS_BACKTRACE),y)
+# Add the AS_NEEDED entry for libubacktrace.so
+ if [ -f $(top_builddir)lib/libc.so -a -f $(PREFIX)$(RUNTIME_PREFIX)lib/$(SHARED_MAJORNAME) ] ; then \
+ echo "GROUP ( $(UBACKTRACE_ASNEEDED) )" >> $(PREFIX)$(DEVEL_PREFIX)lib/libc.so; \
+ fi
+endif
ifeq ($(UCLIBC_HAS_THREADS),y)
ifneq ($(LINUXTHREADS_OLD),y)
ifeq ($(HARDWIRED_ABSPATH),y)
diff --git a/Makerules b/Makerules
index cb1c554bc..2e9ca05bf 100644
--- a/Makerules
+++ b/Makerules
@@ -32,12 +32,12 @@ shared_objs = $(libc-y:.o=.os) $(libc-shared-y) $(libc-nonshared-y) \
$(libpthread-so-y) $(libpthread-nonshared-y) $(libthread_db-so-y) \
$(libresolv-so-y) $(librt-so-y) \
$(ldso-y) \
- $(libutil-so-y)
+ $(libutil-so-y) $(libubacktrace-so-y)
ar_objs = $(libc-y) $(libc-static-y) $(libcrypt-a-y) \
$(libdl-a-y) $(libintl-a-y) $(libm-a-y) $(libnsl-a-y) \
$(libpthread-a-y) $(libthread_db-a-y) \
- $(libresolv-a-y) $(librt-a-y) $(libutil-a-y)
+ $(libresolv-a-y) $(librt-a-y) $(libutil-a-y) $(libubacktrace-a-y)
ifeq ($(DOPIC),y)
ar_objs := $(ar_objs:.o=.os)
endif
@@ -455,7 +455,8 @@ files.dep := $(libc-a-y) $(libc-so-y) $(libc-nonshared-y) \
$(libthread_db-a-y) $(libthread_db-so-y) $(libpthread-generated-y) \
$(librt-a-y) $(librt-so-y) $(libresolv-a-y) $(libresolv-so-y) \
$(libcrypt-a-y) $(libcrypt-so-y) $(libutil-a-y) $(libutil-so-y) \
- $(libnsl-a-y) $(libnsl-so-y) $(ldso-y) $(libdl-a-y) $(libdl-so-y)
+ $(libnsl-a-y) $(libnsl-so-y) $(ldso-y) $(libdl-a-y) $(libdl-so-y) \
+ $(libubacktrace-a-y) $(libubacktrace-so-y)
.depends.dep := \
$(patsubst %.s,%.s.dep,$(filter %.s,$(files.dep))) \
$(patsubst %.o,%.o.dep,$(filter %.o,$(files.dep))) \
diff --git a/Rules.mak b/Rules.mak
index 89127043c..ade86c6ac 100644
--- a/Rules.mak
+++ b/Rules.mak
@@ -118,7 +118,7 @@ export MAJOR_VERSION MINOR_VERSION SUBLEVEL VERSION ABI_VERSION LC_ALL
LIBC := libc
SHARED_LIBNAME := $(LIBC).so.$(ABI_VERSION)
-
+UBACKTRACE_DSO := libubacktrace.so.$(MAJOR_VERSION)
ifneq ($(findstring $(TARGET_ARCH) , hppa64 ia64 mips64 powerpc64 s390x sparc64 x86_64 ),)
UCLIBC_LDSO_NAME := ld64-uClibc
ARCH_NATIVE_BIT := 64
@@ -528,6 +528,13 @@ link.asneeded = $(if $(and $(CC_FLAG_ASNEEDED),$(CC_FLAG_NO_ASNEEDED)),$(CC_FLAG
# Check for AS_NEEDED support in linker script (binutils>=2.16.1 has it)
ifndef ASNEEDED
export ASNEEDED:=$(shell $(LD) --help 2>/dev/null | grep -q -- --as-needed && echo "AS_NEEDED ( $(UCLIBC_LDSO) )" || echo "$(UCLIBC_LDSO)")
+ifeq ($(UCLIBC_HAS_BACKTRACE),y)
+# Only used in installed libc.so linker script
+UBACKTRACE_FULL_NAME := $(RUNTIME_PREFIX)lib/$(UBACKTRACE_DSO)
+export UBACKTRACE_ASNEEDED:=$(shell $(LD) --help 2>/dev/null | grep -q -- --as-needed && echo "AS_NEEDED ( $(UBACKTRACE_FULL_NAME) )" || echo "$(UBACKTRACE_FULL_NAME)")
+else
+export UBACKTRACE_ASNEEDED:=""
+endif
endif
# Add a bunch of extra pedantic annoyingly strict checks
diff --git a/extra/Configs/Config.in b/extra/Configs/Config.in
index 7f0ac9db6..e8d522d71 100644
--- a/extra/Configs/Config.in
+++ b/extra/Configs/Config.in
@@ -2308,6 +2308,25 @@ config UCLIBC_MALLOC_DEBUGGING
Because this increases the size of malloc appreciably (due to strings
etc), you should say N unless you need to debug a malloc problem.
+config UCLIBC_HAS_BACKTRACE
+ bool "Add support for application self-debugging"
+ depends on HAVE_SHARED && TARGET_sh
+ default n
+ help
+ Answer Y here to compile support for application self-debugging, by adding
+ a new shared object "libubacktrace.so" that provides the following new
+ functions:
+ backtrace, backtrace_symbols, backtrace_symbols_fd
+
+ The backtrace functionality is currently supported on SH platform, and it
+ based on dwarf2 informations to properly work, so any application that
+ want to use backtrace needs to be built with -fexceptions flag.
+
+ The symbol names may be unavailable without the use of special linker
+ options. For systems using the GNU linker, it is necessary to use the
+ -rdynamic linker option too. Note that names of "static" functions are not
+ exposed, and won't be available in the backtrace.
+
config WARNINGS
string "Compiler Warnings"
default "-Wall"
diff --git a/include/execinfo.h b/include/execinfo.h
new file mode 100644
index 000000000..c1614cc1f
--- /dev/null
+++ b/include/execinfo.h
@@ -0,0 +1,44 @@
+/* Copyright (C) 1998, 1999, 2004, 2005 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _EXECINFO_H
+#define _EXECINFO_H 1
+
+#include <features.h>
+
+__BEGIN_DECLS
+
+/* Store up to SIZE return address of the current program state in
+ ARRAY and return the exact number of values stored. */
+extern int backtrace (void **__array, int __size) __nonnull ((1));
+
+
+/* Return names of functions from the backtrace list in ARRAY in a newly
+ malloc()ed memory block. */
+extern char **backtrace_symbols (void *__const *__array, int __size)
+ __THROW __nonnull ((1));
+
+
+/* This function is similar to backtrace_symbols() but it writes the result
+ immediately to a file. */
+extern void backtrace_symbols_fd (void *__const *__array, int __size, int __fd)
+ __THROW __nonnull ((1));
+
+__END_DECLS
+
+#endif /* execinfo.h */
diff --git a/libubacktrace/Makefile b/libubacktrace/Makefile
new file mode 100644
index 000000000..0f746383c
--- /dev/null
+++ b/libubacktrace/Makefile
@@ -0,0 +1,14 @@
+# Makefile for uClibc (libubacktrace)
+#
+# Copyright (C) 2010 STMicroelectronics Ltd
+# Author(s): Carmelo Amoroso <carmelo.amoroso@st.com>
+#
+# Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+#
+
+top_srcdir=../
+top_builddir=../
+include $(top_builddir)Rules.mak
+all: libs
+include Makefile.in
+include $(top_srcdir)Makerules
diff --git a/libubacktrace/Makefile.in b/libubacktrace/Makefile.in
new file mode 100644
index 000000000..c1dd5d7ab
--- /dev/null
+++ b/libubacktrace/Makefile.in
@@ -0,0 +1,84 @@
+# Makefile for uClibc (libubacktrace)
+#
+# Copyright (C) 2010 STMicroelectronics Ltd
+# Author: Carmelo Amoroso <carmelo.amoroso@st.com>
+
+# Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+#
+
+subdirs += libubacktrace
+
+CFLAGS-libubacktrace := -DNOT_IN_libc -DIS_IN_libubacktrace $(SSP_ALL_CFLAGS)
+
+LDFLAGS-libubacktrace.so := $(LDFLAGS) $(top_builddir)lib/libdl-$(VERSION).so
+
+LIBS-libubacktrace.so := $(LIBS)
+
+libubacktrace_FULL_NAME := libubacktrace-$(VERSION).so
+
+libubacktrace_DIR := $(top_srcdir)libubacktrace
+libubacktrace_OUT := $(top_builddir)libubacktrace
+libubacktrace_ARCH_DIR := $(libubacktrace_DIR)/sysdeps/$(TARGET_ARCH)
+libubacktrace_ARCH_OUT := $(libubacktrace_OUT)/sysdeps/$(TARGET_ARCH)
+
+-include $(libubacktrace_ARCH_DIR)/Makefile.arch
+
+libubacktrace_SRC-y :=
+libubacktrace_SRC-$(UCLIBC_HAS_BACKTRACE) := backtrace.c backtracesyms.c backtracesymsfd.c
+
+CFLAGS-libubacktrace/sysdeps/$(TARGET_ARCH)/ := $(CFLAGS-libubacktrace)
+
+# remove generic sources, if arch specific version is present
+ifneq ($(strip $(libubacktrace_ARCH_SRC-y)),)
+libubacktrace_SRC-y := $(filter-out $(notdir $(libubacktrace_ARCH_SRC-y)),$(libubacktrace_SRC-y))
+libubacktrace_ARCH_SRC := $(addprefix $(libubacktrace_ARCH_DIR)/,$(libubacktrace_ARCH_SRC-y))
+libubacktrace_ARCH_OBJ := $(patsubst $(libubacktrace_ARCH_DIR)/%.c,$(libubacktrace_ARCH_OUT)/%.o,$(libubacktrace_ARCH_SRC))
+endif
+
+
+libubacktrace_SRC := $(addprefix $(libubacktrace_DIR)/,$(libubacktrace_SRC-y))
+libubacktrace_OBJ := $(patsubst $(libubacktrace_DIR)/%.c,$(libubacktrace_OUT)/%.o,$(libubacktrace_SRC))
+
+libubacktrace_SRCS := $(libubacktrace_SRC) $(libubacktrace_ARCH_SRC)
+libubacktrace_OBJS := $(libubacktrace_OBJ) $(libubacktrace_ARCH_OBJ)
+
+ifeq ($(DOPIC),y)
+libubacktrace-a-y := $(libubacktrace_OBJS:.o=.os)
+else
+libubacktrace-a-y := $(libubacktrace_OBJS)
+endif
+libubacktrace-so-y := $(libubacktrace_OBJS:.o=.os)
+
+lib-a-$(UCLIBC_HAS_BACKTRACE) += $(top_builddir)lib/libubacktrace.a
+lib-so-$(UCLIBC_HAS_BACKTRACE) += $(top_builddir)lib/libubacktrace.so
+
+objclean-y += CLEAN_libubacktrace
+
+ifeq ($(DOMULTI),n)
+ifeq ($(DOPIC),y)
+$(top_builddir)lib/libubacktrace.so: $(top_builddir)lib/libubacktrace.a $(libdl.depend)
+else
+$(top_builddir)lib/libubacktrace.so: $(libubacktrace_OUT)/libubacktrace_so.a $(libdl.depend)
+endif
+ $(call link.so,$(libubacktrace_FULL_NAME),$(ABI_VERSION))
+else
+$(top_builddir)lib/libubacktrace.so: $(libubacktrace_OUT)/libubacktrace.oS | $(libdl.depend)
+ $(call linkm.so,$(libubacktrace_FULL_NAME),$(ABI_VERSION))
+endif
+
+$(libubacktrace_OUT)/libubacktrace_so.a: $(libubacktrace-so-y)
+ $(Q)$(RM) $@
+ $(do_ar)
+
+$(libubacktrace_OUT)/libubacktrace.oS: $(libubacktrace_SRCS)
+ $(Q)$(RM) $@
+ $(compile-m)
+
+$(top_builddir)lib/libubacktrace.a: $(libubacktrace-a-y)
+ $(Q)$(INSTALL) -d $(dir $@)
+ $(Q)$(RM) $@
+ $(do_ar)
+
+CLEAN_libubacktrace:
+ $(do_rm) $(addprefix $(libubacktrace_OUT)/*., o os oS a) \
+ $(addprefix $(libubacktrace_ARCH_OUT)/*., o os oS a)
diff --git a/libubacktrace/backtrace.c b/libubacktrace/backtrace.c
new file mode 100644
index 000000000..872180028
--- /dev/null
+++ b/libubacktrace/backtrace.c
@@ -0,0 +1,19 @@
+/*
+ * Perform stack unwinding by using the _Unwind_Backtrace.
+ *
+ * User application that wants to use backtrace needs to be
+ * compiled with -fexceptions option and -rdynamic to get full
+ * symbols printed.
+
+ * Copyright (C) 2010 STMicroelectronics Ltd
+ * Author(s): Carmelo Amoroso <carmelo.amoroso@st.com>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ *
+ */
+#error "Arch specific implementation must be provided to properly work"
+int backtrace (void **array, int size)
+{
+ return -1;
+}
+
diff --git a/libubacktrace/backtracesyms.c b/libubacktrace/backtracesyms.c
new file mode 100644
index 000000000..4486fee94
--- /dev/null
+++ b/libubacktrace/backtracesyms.c
@@ -0,0 +1,105 @@
+/* Return list with names for address in backtrace.
+ Copyright (C) 1998,1999,2000,2001,2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA.
+
+ Based on glibc/sysdeps/generic/elf/backtracesyms.c
+
+ Copyright (C) 2010 STMicroelectronics Ltd
+ Author(s): Carmelo Amoroso <carmelo.amoroso@st.com>
+ * Modified to work with uClibc
+ - updated headers inclusion
+ - updated formatting and style
+ - updated to use dladdr from libdl */
+
+#include <execinfo.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <dlfcn.h>
+#include <link.h> /* required for __ELF_NATIVE_CLASS */
+
+#if __ELF_NATIVE_CLASS == 32
+# define WORD_WIDTH 8
+#else
+/* We assyme 64bits. */
+# define WORD_WIDTH 16
+#endif
+
+
+char ** backtrace_symbols (void *const *array, int size)
+{
+ Dl_info info[size];
+ int status[size];
+ int cnt;
+ size_t total = 0;
+ char **result;
+
+ /* Fill in the information we can get from `dladdr'. */
+ for (cnt = 0; cnt < size; ++cnt) {
+ status[cnt] = dladdr (array[cnt], &info[cnt]);
+ if (status[cnt] && info[cnt].dli_fname &&
+ info[cnt].dli_fname[0] != '\0')
+ /*
+ * We have some info, compute the length of the string which will be
+ * "<file-name>(<sym-name>) [+offset].
+ */
+ total += (strlen (info[cnt].dli_fname ?: "") +
+ (info[cnt].dli_sname ?
+ strlen (info[cnt].dli_sname) + 3 + WORD_WIDTH + 3 : 1)
+ + WORD_WIDTH + 5);
+ else
+ total += 5 + WORD_WIDTH;
+ }
+
+ /* Allocate memory for the result. */
+ result = (char **) malloc (size * sizeof (char *) + total);
+ if (result != NULL) {
+ char *last = (char *) (result + size);
+ for (cnt = 0; cnt < size; ++cnt) {
+ result[cnt] = last;
+
+ if (status[cnt] && info[cnt].dli_fname
+ && info[cnt].dli_fname[0] != '\0') {
+
+ char buf[20];
+
+ if (array[cnt] >= (void *) info[cnt].dli_saddr)
+ sprintf (buf, "+%#lx",
+ (unsigned long)(array[cnt] - info[cnt].dli_saddr));
+ else
+ sprintf (buf, "-%#lx",
+ (unsigned long)(info[cnt].dli_saddr - array[cnt]));
+
+ last += 1 + sprintf (last, "%s%s%s%s%s[%p]",
+ info[cnt].dli_fname ?: "",
+ info[cnt].dli_sname ? "(" : "",
+ info[cnt].dli_sname ?: "",
+ info[cnt].dli_sname ? buf : "",
+ info[cnt].dli_sname ? ") " : " ",
+ array[cnt]);
+ } else
+ last += 1 + sprintf (last, "[%p]", array[cnt]);
+ }
+ assert (last <= (char *) result + size * sizeof (char *) + total);
+ }
+
+ return result;
+}
diff --git a/libubacktrace/backtracesymsfd.c b/libubacktrace/backtracesymsfd.c
new file mode 100644
index 000000000..66d7687ca
--- /dev/null
+++ b/libubacktrace/backtracesymsfd.c
@@ -0,0 +1,116 @@
+/* Write formatted list with names for addresses in backtrace to a file.
+ Copyright (C) 1998, 2000, 2003, 2005 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA.
+
+ Based on glibc/sysdeps/generic/elf/backtracesymsfd.c
+
+ Copyright (C) 2010 STMicroelectronics Ltd
+ Author(s): Carmelo Amoroso <carmelo.amoroso@st.com>
+ * Modified to work with uClibc
+ - updated headers inclusion
+ - updated formatting and style
+ - updated to use dladdr from libdl
+ - updated to use snprintf instead of _itoa_word */
+
+#include <execinfo.h>
+#include <string.h>
+#include <sys/uio.h>
+#include <dlfcn.h>
+#include <stdio.h>
+#include <link.h> /* required for __ELF_NATIVE_CLASS */
+
+#if __ELF_NATIVE_CLASS == 32
+# define WORD_WIDTH 8
+#else
+/* We assyme 64bits. */
+# define WORD_WIDTH 16
+#endif
+
+#define BUF_SIZE (WORD_WIDTH + 1)
+
+void backtrace_symbols_fd (void *const *array, int size, int fd)
+{
+ struct iovec iov[9];
+ int cnt;
+
+ for (cnt = 0; cnt < size; ++cnt) {
+ char buf[BUF_SIZE];
+ Dl_info info;
+ size_t last = 0;
+ size_t len = 0;
+
+ memset(buf, 0, sizeof(buf));
+ if (dladdr (array[cnt], &info)
+ && info.dli_fname && info.dli_fname[0] != '\0') {
+ /* Name of the file. */
+ iov[0].iov_base = (void *) info.dli_fname;
+ iov[0].iov_len = strlen (info.dli_fname);
+ last = 1;
+
+ /* Symbol name. */
+ if (info.dli_sname != NULL) {
+ char buf2[BUF_SIZE];
+ memset(buf2, 0, sizeof(buf2));
+ size_t diff;
+
+ iov[1].iov_base = (void *) "(";
+ iov[1].iov_len = 1;
+ iov[2].iov_base = (void *) info.dli_sname;
+ iov[2].iov_len = strlen (info.dli_sname);
+
+ if (array[cnt] >= (void *) info.dli_saddr) {
+ iov[3].iov_base = (void *) "+0x";
+ diff = array[cnt] - info.dli_saddr;
+ } else {
+ iov[3].iov_base = (void *) "-0x";
+ diff = info.dli_saddr - array[cnt];
+ }
+
+ iov[3].iov_len = 3;
+
+ /* convert diff to a string in hex format */
+ len = snprintf(buf2, sizeof(buf2), "%lx", (unsigned long) diff);
+ iov[4].iov_base = buf2;
+ iov[4].iov_len = len;
+
+ iov[5].iov_base = (void *) ")";
+ iov[5].iov_len = 1;
+
+ last = 6;
+ }
+ }
+
+ iov[last].iov_base = (void *) "[0x";
+ iov[last].iov_len = 3;
+ ++last;
+
+ /* convert array[cnt] to a string in hex format */
+ len = snprintf(buf, sizeof(buf), "%lx", (unsigned long) array[cnt]);
+ iov[last].iov_base = buf;
+ iov[last].iov_len = len;
+
+ ++last;
+
+ iov[last].iov_base = (void *) "]\n";
+ iov[last].iov_len = 2;
+ ++last;
+
+ writev (fd, iov, last);
+ }
+}
diff --git a/libubacktrace/sysdeps/sh/Makefile.arch b/libubacktrace/sysdeps/sh/Makefile.arch
new file mode 100644
index 000000000..9b0de385b
--- /dev/null
+++ b/libubacktrace/sysdeps/sh/Makefile.arch
@@ -0,0 +1,12 @@
+# Makefile for uClibc (sh/libubacktrace)
+#
+# Copyright (C) 2010 STMicroelectronics Ltd
+# Author: Carmelo Amoroso <carmelo.amoroso@st.com>
+
+# Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+#
+
+libubacktrace_ARCH_SRC-y := backtrace.c
+
+# -fexections is required for backtrace to work using dwarf2
+CFLAGS-backtrace.c := -fexceptions
diff --git a/libubacktrace/sysdeps/sh/backtrace.c b/libubacktrace/sysdeps/sh/backtrace.c
new file mode 100644
index 000000000..18b91b1bb
--- /dev/null
+++ b/libubacktrace/sysdeps/sh/backtrace.c
@@ -0,0 +1,84 @@
+/*
+ * Perform stack unwinding by using the _Unwind_Backtrace.
+ *
+ * User application that wants to use backtrace needs to be
+ * compiled with -fexceptions option and -rdynamic to get full
+ * symbols printed.
+ *
+ * Copyright (C) 2009, 2010 STMicroelectronics Ltd.
+ *
+ * Author(s): Giuseppe Cavallaro <peppe.cavallaro@st.com>
+ * - Initial implementation for glibc
+ *
+ * Author(s): Carmelo Amoroso <carmelo.amoroso@st.com>
+ * - Reworked for uClibc
+ * - use dlsym/dlopen from libdl
+ * - rewrite initialisation to not use libc_once
+ * - make it available in static link too
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ *
+ */
+
+#include <execinfo.h>
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <unwind.h>
+#include <assert.h>
+#include <stdio.h>
+
+struct trace_arg
+{
+ void **array;
+ int cnt, size;
+};
+
+static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *);
+static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *);
+
+static void backtrace_init (void)
+{
+ void *handle = dlopen ("libgcc_s.so.1", RTLD_LAZY);
+
+ if (handle == NULL
+ || ((unwind_backtrace = dlsym (handle, "_Unwind_Backtrace")) == NULL)
+ || ((unwind_getip = dlsym (handle, "_Unwind_GetIP")) == NULL)) {
+ printf("libgcc_s.so.1 must be installed for backtrace to work\n");
+ abort();
+ }
+}
+
+static _Unwind_Reason_Code
+backtrace_helper (struct _Unwind_Context *ctx, void *a)
+{
+ struct trace_arg *arg = a;
+
+ assert (unwind_getip != NULL);
+
+ /* We are first called with address in the __backtrace function. Skip it. */
+ if (arg->cnt != -1)
+ arg->array[arg->cnt] = (void *) unwind_getip (ctx);
+ if (++arg->cnt == arg->size)
+ return _URC_END_OF_STACK;
+ return _URC_NO_REASON;
+}
+
+/*
+ * Perform stack unwinding by using the _Unwind_Backtrace.
+ *
+ * User application that wants to use backtrace needs to be
+ * compiled with -fexceptions option and -rdynamic to get full
+ * symbols printed.
+ */
+int backtrace (void **array, int size)
+{
+ struct trace_arg arg = { .array = array, .size = size, .cnt = -1 };
+
+ if (unwind_backtrace == NULL)
+ backtrace_init();
+
+ if (size >= 1)
+ unwind_backtrace (backtrace_helper, &arg);
+
+ return arg.cnt != -1 ? arg.cnt : 0;
+}