From 8db222e36ae777e6aec8c61c616838a86258e99f Mon Sep 17 00:00:00 2001 From: =?utf8?q?=C3=89rico=20Rolim?= Date: Mon, 1 Feb 2021 21:16:56 -0300 Subject: [PATCH] libdwfl: use GNU strerror_r only when available. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Some C libraries don't provide the GNU version of strerror_r, only the XSI-compliant one. We use the GNU version when available, since it fits the code better, and otherwise use the XSI-compliant one. https://sourceware.org/bugzilla/show_bug.cgi?id=21010 Signed-off-by: Érico Rolim --- ChangeLog | 4 ++++ configure.ac | 5 +++++ libdwfl/ChangeLog | 4 ++++ libdwfl/dwfl_error.c | 17 ++++++++++++++++- 4 files changed, 29 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 142caa2..c8f921a 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,7 @@ +2021-02-01 Érico Nogueira + + * configure.ac: Check for GNU strerror_r. + 2021-01-12 Dmitry V. Levin * configure.ac [--enable-gcov]: Check for gcov, lcov, and genhtml. diff --git a/configure.ac b/configure.ac index 346ab80..47db847 100644 --- a/configure.ac +++ b/configure.ac @@ -428,6 +428,11 @@ AC_CHECK_DECLS([mempcpy],[],[], AC_CHECK_FUNCS([process_vm_readv]) +old_CFLAGS="$CFLAGS" +CFLAGS="$CFLAGS -D_GNU_SOURCE" +AC_FUNC_STRERROR_R() +CFLAGS="$old_CFLAGS" + AC_CHECK_LIB([stdc++], [__cxa_demangle], [dnl AC_DEFINE([USE_DEMANGLE], [1], [Defined if demangling is enabled])]) AM_CONDITIONAL(DEMANGLE, test "x$ac_cv_lib_stdcpp___cxa_demangle" = "xyes") diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog index 5058f5f..d107e78 100644 --- a/libdwfl/ChangeLog +++ b/libdwfl/ChangeLog @@ -1,3 +1,7 @@ +2021-02-01 Érico Nogueira + + * dwfl_error.c (strerror_r): Only use the GNU version when available. + 2021-01-08 Timm Bäder * elf-from-memory.c (elf_from_remote_memory): Add for loop over diff --git a/libdwfl/dwfl_error.c b/libdwfl/dwfl_error.c index 7bcf61c..a5c683a 100644 --- a/libdwfl/dwfl_error.c +++ b/libdwfl/dwfl_error.c @@ -137,6 +137,21 @@ __libdwfl_seterrno (Dwfl_Error error) } +static const char * +errnomsg(int error) +{ + /* Won't be changed by strerror_r, but not const so compiler doesn't throw warning */ + static char unknown[] = "unknown error"; + +#ifdef STRERROR_R_CHAR_P + return strerror_r (error, unknown, 0); +#else + /* To store the error message from strerror_r in a thread-safe manner */ + static __thread char msg[128]; + return strerror_r (error, msg, sizeof (msg)) ? unknown : msg; +#endif +} + const char * dwfl_errmsg (int error) { @@ -154,7 +169,7 @@ dwfl_errmsg (int error) switch (error &~ 0xffff) { case OTHER_ERROR (ERRNO): - return strerror_r (error & 0xffff, "bad", 0); + return errnomsg (error & 0xffff); case OTHER_ERROR (LIBELF): return elf_errmsg (error & 0xffff); case OTHER_ERROR (LIBDW): -- 2.7.4