From 37eb913ed8c4798b736e678f4dbd9f4a91a68f74 Mon Sep 17 00:00:00 2001 From: Salvatore Cro Date: Thu, 9 Sep 2010 15:45:44 +0200 Subject: 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 --- libubacktrace/backtracesyms.c | 105 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) create mode 100644 libubacktrace/backtracesyms.c (limited to 'libubacktrace/backtracesyms.c') 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 , 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 + * Modified to work with uClibc + - updated headers inclusion + - updated formatting and style + - updated to use dladdr from libdl */ + +#include +#include +#include +#include +#include + +#include +#include /* 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 + * "() [+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; +} -- cgit v1.2.3