The code in libbacktrace had a race when doing parallel initialization: if two threads start to initialize at the same time, and one completes first, the other, while running in backtrace_initialize, may see that the structure is initialized and thus not change *fileline_fn. The caller will then set state->fileline_fn to *fileline_fn, but since backtrace_initialize has not changed it that will be NULL. The effect is that if the timing is right the code can then call a NULL function pointer.
This patch fixes the problem by always initializing *fileline_fn in backtrace_initialize. It adds a test in ttest.c that does 10 backtraces in parallel with an new state. To make writing the test easier I copied the test support functions out of btest.c into testlib.c. While doing that I eliminated some of the duplication in edtest.c by making that use testlib.c as well. Bootstrapped and ran Go testsuite on x86_64-pc-linux-gnu. Committed to mainline. Ian
Index: Makefile.am =================================================================== --- Makefile.am (revision 249070) +++ Makefile.am (working copy) @@ -89,7 +89,7 @@ TESTS = $(check_PROGRAMS) if NATIVE -btest_SOURCES = btest.c +btest_SOURCES = btest.c testlib.c btest_CFLAGS = $(AM_CFLAGS) -g -O btest_LDADD = libbacktrace.la @@ -100,7 +100,7 @@ stest_LDADD = libbacktrace.la check_PROGRAMS += stest -edtest_SOURCES = edtest.c edtest2_build.c +edtest_SOURCES = edtest.c edtest2_build.c testlib.c edtest_LDADD = libbacktrace.la check_PROGRAMS += edtest @@ -111,6 +111,16 @@ gen_edtest2_build: $(srcdir)/edtest2.c $(SHELL) $(srcdir)/../move-if-change tmp-edtest2_build.c edtest2_build.c echo timestamp > $@ +if HAVE_PTHREAD + +check_PROGRAMS += ttest + +ttest_SOURCES = ttest.c testlib.c +ttest_CFLAGS = -pthread +ttest_LDADD = libbacktrace.la + +endif HAVE_PTHREAD + endif NATIVE # We can't use automake's automatic dependency tracking, because it Index: btest.c =================================================================== --- btest.c (revision 249070) +++ btest.c (working copy) @@ -43,237 +43,7 @@ POSSIBILITY OF SUCH DAMAGE. */ #include "backtrace.h" #include "backtrace-supported.h" -/* Portable attribute syntax. Actually some of these tests probably - won't work if the attributes are not recognized. */ - -#ifndef GCC_VERSION -# define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) -#endif - -#if (GCC_VERSION < 2007) -# define __attribute__(x) -#endif - -#ifndef ATTRIBUTE_UNUSED -# define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) -#endif - -/* Used to collect backtrace info. */ - -struct info -{ - char *filename; - int lineno; - char *function; -}; - -/* Passed to backtrace callback function. */ - -struct bdata -{ - struct info *all; - size_t index; - size_t max; - int failed; -}; - -/* Passed to backtrace_simple callback function. */ - -struct sdata -{ - uintptr_t *addrs; - size_t index; - size_t max; - int failed; -}; - -/* Passed to backtrace_syminfo callback function. */ - -struct symdata -{ - const char *name; - uintptr_t val, size; - int failed; -}; - -/* The backtrace state. */ - -static void *state; - -/* The number of failures. */ - -static int failures; - -/* Return the base name in a path. */ - -static const char * -base (const char *p) -{ - const char *last; - const char *s; - - last = NULL; - for (s = p; *s != '\0'; ++s) - { - if (IS_DIR_SEPARATOR (*s)) - last = s + 1; - } - return last != NULL ? last : p; -} - -/* Check an entry in a struct info array. */ - -static void -check (const char *name, int index, const struct info *all, int want_lineno, - const char *want_function, int *failed) -{ - if (*failed) - return; - if (all[index].filename == NULL || all[index].function == NULL) - { - fprintf (stderr, "%s: [%d]: missing file name or function name\n", - name, index); - *failed = 1; - return; - } - if (strcmp (base (all[index].filename), "btest.c") != 0) - { - fprintf (stderr, "%s: [%d]: got %s expected test.c\n", name, index, - all[index].filename); - *failed = 1; - } - if (all[index].lineno != want_lineno) - { - fprintf (stderr, "%s: [%d]: got %d expected %d\n", name, index, - all[index].lineno, want_lineno); - *failed = 1; - } - if (strcmp (all[index].function, want_function) != 0) - { - fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index, - all[index].function, want_function); - *failed = 1; - } -} - -/* The backtrace callback function. */ - -static int -callback_one (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, - const char *filename, int lineno, const char *function) -{ - struct bdata *data = (struct bdata *) vdata; - struct info *p; - - if (data->index >= data->max) - { - fprintf (stderr, "callback_one: callback called too many times\n"); - data->failed = 1; - return 1; - } - - p = &data->all[data->index]; - if (filename == NULL) - p->filename = NULL; - else - { - p->filename = strdup (filename); - assert (p->filename != NULL); - } - p->lineno = lineno; - if (function == NULL) - p->function = NULL; - else - { - p->function = strdup (function); - assert (p->function != NULL); - } - ++data->index; - - return 0; -} - -/* An error callback passed to backtrace. */ - -static void -error_callback_one (void *vdata, const char *msg, int errnum) -{ - struct bdata *data = (struct bdata *) vdata; - - fprintf (stderr, "%s", msg); - if (errnum > 0) - fprintf (stderr, ": %s", strerror (errnum)); - fprintf (stderr, "\n"); - data->failed = 1; -} - -/* The backtrace_simple callback function. */ - -static int -callback_two (void *vdata, uintptr_t pc) -{ - struct sdata *data = (struct sdata *) vdata; - - if (data->index >= data->max) - { - fprintf (stderr, "callback_two: callback called too many times\n"); - data->failed = 1; - return 1; - } - - data->addrs[data->index] = pc; - ++data->index; - - return 0; -} - -/* An error callback passed to backtrace_simple. */ - -static void -error_callback_two (void *vdata, const char *msg, int errnum) -{ - struct sdata *data = (struct sdata *) vdata; - - fprintf (stderr, "%s", msg); - if (errnum > 0) - fprintf (stderr, ": %s", strerror (errnum)); - fprintf (stderr, "\n"); - data->failed = 1; -} - -/* The backtrace_syminfo callback function. */ - -static void -callback_three (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, - const char *symname, uintptr_t symval, - uintptr_t symsize) -{ - struct symdata *data = (struct symdata *) vdata; - - if (symname == NULL) - data->name = NULL; - else - { - data->name = strdup (symname); - assert (data->name != NULL); - } - data->val = symval; - data->size = symsize; -} - -/* The backtrace_syminfo error callback function. */ - -static void -error_callback_three (void *vdata, const char *msg, int errnum) -{ - struct symdata *data = (struct symdata *) vdata; - - fprintf (stderr, "%s", msg); - if (errnum > 0) - fprintf (stderr, ": %s", strerror (errnum)); - fprintf (stderr, "\n"); - data->failed = 1; -} +#include "testlib.h" /* Test the backtrace function with non-inlined functions. */ @@ -325,9 +95,9 @@ f3 (int f1line, int f2line) data.failed = 1; } - check ("test1", 0, all, f3line, "f3", &data.failed); - check ("test1", 1, all, f2line, "f2", &data.failed); - check ("test1", 2, all, f1line, "test1", &data.failed); + check ("test1", 0, all, f3line, "f3", "btest.c", &data.failed); + check ("test1", 1, all, f2line, "f2", "btest.c", &data.failed); + check ("test1", 2, all, f1line, "test1", "btest.c", &data.failed); printf ("%s: backtrace_full noinline\n", data.failed ? "FAIL" : "PASS"); @@ -377,9 +147,9 @@ f13 (int f1line, int f2line) data.failed = 1; } - check ("test2", 0, all, f3line, "f13", &data.failed); - check ("test2", 1, all, f2line, "f12", &data.failed); - check ("test2", 2, all, f1line, "test2", &data.failed); + check ("test2", 0, all, f3line, "f13", "btest.c", &data.failed); + check ("test2", 1, all, f2line, "f12", "btest.c", &data.failed); + check ("test2", 2, all, f1line, "test2", "btest.c", &data.failed); printf ("%s: backtrace_full inline\n", data.failed ? "FAIL" : "PASS"); @@ -462,9 +232,9 @@ f23 (int f1line, int f2line) } } - check ("test3", 0, all, f3line, "f23", &bdata.failed); - check ("test3", 1, all, f2line, "f22", &bdata.failed); - check ("test3", 2, all, f1line, "test3", &bdata.failed); + check ("test3", 0, all, f3line, "f23", "btest.c", &bdata.failed); + check ("test3", 1, all, f2line, "f22", "btest.c", &bdata.failed); + check ("test3", 2, all, f1line, "test3", "btest.c", &bdata.failed); if (bdata.failed) data.failed = 1; @@ -600,9 +370,9 @@ f33 (int f1line, int f2line) bdata.failed = 1; } - check ("test4", 0, all, f3line, "f33", &bdata.failed); - check ("test4", 1, all, f2line, "f32", &bdata.failed); - check ("test4", 2, all, f1line, "test4", &bdata.failed); + check ("test4", 0, all, f3line, "f33", "btest.c", &bdata.failed); + check ("test4", 1, all, f2line, "f32", "btest.c", &bdata.failed); + check ("test4", 2, all, f1line, "test4", "btest.c", &bdata.failed); if (bdata.failed) data.failed = 1; @@ -686,17 +456,6 @@ test5 (void) return failures; } -static void -error_callback_create (void *data ATTRIBUTE_UNUSED, const char *msg, - int errnum) -{ - fprintf (stderr, "%s", msg); - if (errnum > 0) - fprintf (stderr, ": %s", strerror (errnum)); - fprintf (stderr, "\n"); - exit (EXIT_FAILURE); -} - /* Run all the tests. */ int Index: configure.ac =================================================================== --- configure.ac (revision 249070) +++ configure.ac (working copy) @@ -355,6 +355,23 @@ if test "$have_getexecname" = "yes"; the AC_DEFINE(HAVE_GETEXECNAME, 1, [Define if getexecname is available.]) fi +dnl Test whether the compiler supports the -pthread option. +AC_CACHE_CHECK([whether -pthread is supported], +[libgo_cv_lib_pthread], +[CFLAGS_hold=$CFLAGS +CFLAGS="$CFLAGS -pthread" +AC_COMPILE_IFELSE([[int i;]], +[libgo_cv_lib_pthread=yes], +[libgo_cv_lib_pthread=no]) +CFLAGS=$CFLAGS_hold]) +PTHREAD_CFLAGS= +if test "$libgo_cv_lib_pthread" = yes; then + PTHREAD_CFLAGS=-pthread +fi +AC_SUBST(PTHREAD_CFLAGS) + +AM_CONDITIONAL(HAVE_PTHREAD, test "$libgo_cv_lib_pthread" = yes) + AC_CACHE_CHECK([whether tests can run], [libbacktrace_cv_sys_native], [AC_RUN_IFELSE([AC_LANG_PROGRAM([], [return 0;])], Index: edtest.c =================================================================== --- edtest.c (revision 249070) +++ edtest.c (working copy) @@ -41,19 +41,7 @@ POSSIBILITY OF SUCH DAMAGE. */ #include "backtrace-supported.h" #include "internal.h" -#if defined(__MSDOS__) || defined(_WIN32) || defined(__OS2__) || defined (__CYGWIN__) -# define IS_DIR_SEPARATOR(c) ((c) == '/' || (c) == '\\') -#else -# define IS_DIR_SEPARATOR(c) ((c) == '/') -#endif - -/* The backtrace state. */ - -static void *state; - -/* The number of failures. */ - -int failures = 0; +#include "testlib.h" static int test1 (void) __attribute__ ((noinline, unused)); static int test1 (void) __attribute__ ((noinline, unused)); @@ -68,128 +56,6 @@ test1 (void) return f2 (__LINE__) + 1; } -/* Used to collect backtrace info. */ - -struct info -{ - char *filename; - int lineno; - char *function; -}; - -/* Return the base name in a path. */ - -static const char * -base (const char *p) -{ - const char *last; - const char *s; - - last = NULL; - for (s = p; *s != '\0'; ++s) - { - if (IS_DIR_SEPARATOR (*s)) - last = s + 1; - } - return last != NULL ? last : p; -} - -/* Check an entry in a struct info array. */ - -static void -check (const char *name, int index, const struct info *all, int want_lineno, - const char *want_function, const char *want_file, int *failed) -{ - if (*failed) - return; - if (all[index].filename == NULL || all[index].function == NULL) - { - fprintf (stderr, "%s: [%d]: missing file name or function name\n", - name, index); - *failed = 1; - return; - } - if (strcmp (base (all[index].filename), want_file) != 0) - { - fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index, - all[index].filename, want_file); - *failed = 1; - } - if (all[index].lineno != want_lineno) - { - fprintf (stderr, "%s: [%d]: got %d expected %d\n", name, index, - all[index].lineno, want_lineno); - *failed = 1; - } - if (strcmp (all[index].function, want_function) != 0) - { - fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index, - all[index].function, want_function); - *failed = 1; - } -} - -/* Passed to backtrace callback function. */ - -struct bdata -{ - struct info *all; - size_t index; - size_t max; - int failed; -}; - -/* An error callback passed to backtrace. */ - -static void -error_callback_one (void *vdata, const char *msg, int errnum) -{ - struct bdata *data = (struct bdata *) vdata; - - fprintf (stderr, "%s", msg); - if (errnum > 0) - fprintf (stderr, ": %s", strerror (errnum)); - fprintf (stderr, "\n"); - data->failed = 1; -} - -/* The backtrace callback function. */ - -static int -callback_one (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, - const char *filename, int lineno, const char *function) -{ - struct bdata *data = (struct bdata *) vdata; - struct info *p; - - if (data->index >= data->max) - { - fprintf (stderr, "callback_one: callback called too many times\n"); - data->failed = 1; - return 1; - } - - p = &data->all[data->index]; - if (filename == NULL) - p->filename = NULL; - else - { - p->filename = strdup (filename); - assert (p->filename != NULL); - } - p->lineno = lineno; - if (function == NULL) - p->function = NULL; - else - { - p->function = strdup (function); - assert (p->function != NULL); - } - ++data->index; - - return 0; -} - int f3 (int f1line, int f2line) { @@ -232,17 +98,6 @@ f3 (int f1line, int f2line) return failures; } -static void -error_callback_create (void *data ATTRIBUTE_UNUSED, const char *msg, - int errnum) -{ - fprintf (stderr, "%s", msg); - if (errnum > 0) - fprintf (stderr, ": %s", strerror (errnum)); - fprintf (stderr, "\n"); - exit (EXIT_FAILURE); -} - int main (int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED) { Index: elf.c =================================================================== --- elf.c (revision 249070) +++ elf.c (working copy) @@ -962,18 +962,12 @@ backtrace_initialize (struct backtrace_s } if (!state->threaded) - { - if (state->fileline_fn == NULL || state->fileline_fn == elf_nodebug) - *fileline_fn = elf_fileline_fn; - } + *fileline_fn = state->fileline_fn; else - { - fileline current_fn; + *fileline_fn = backtrace_atomic_load_pointer (&state->fileline_fn); - current_fn = backtrace_atomic_load_pointer (&state->fileline_fn); - if (current_fn == NULL || current_fn == elf_nodebug) - *fileline_fn = elf_fileline_fn; - } + if (*fileline_fn == NULL || *fileline_fn == elf_nodebug) + *fileline_fn = elf_fileline_fn; return 1; } Index: testlib.c =================================================================== --- testlib.c (revision 0) +++ testlib.c (working copy) @@ -0,0 +1,234 @@ +/* testlib.h -- test functions for libbacktrace library + Copyright (C) 2012-2017 Free Software Foundation, Inc. + Written by Ian Lance Taylor, Google. + +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. */ + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "filenames.h" + +#include "backtrace.h" + +#include "testlib.h" + +/* The backtrace state. */ + +void *state; + +/* The number of failures. */ + +int failures; + +/* Return the base name in a path. */ + +const char * +base (const char *p) +{ + const char *last; + const char *s; + + last = NULL; + for (s = p; *s != '\0'; ++s) + { + if (IS_DIR_SEPARATOR (*s)) + last = s + 1; + } + return last != NULL ? last : p; +} + +/* Check an entry in a struct info array. */ + +void +check (const char *name, int index, const struct info *all, int want_lineno, + const char *want_function, const char *want_file, int *failed) +{ + if (*failed) + return; + if (all[index].filename == NULL || all[index].function == NULL) + { + fprintf (stderr, "%s: [%d]: missing file name or function name\n", + name, index); + *failed = 1; + return; + } + if (strcmp (base (all[index].filename), want_file) != 0) + { + fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index, + all[index].filename, want_file); + *failed = 1; + } + if (all[index].lineno != want_lineno) + { + fprintf (stderr, "%s: [%d]: got %d expected %d\n", name, index, + all[index].lineno, want_lineno); + *failed = 1; + } + if (strcmp (all[index].function, want_function) != 0) + { + fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index, + all[index].function, want_function); + *failed = 1; + } +} + +/* The backtrace callback function. */ + +int +callback_one (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, + const char *filename, int lineno, const char *function) +{ + struct bdata *data = (struct bdata *) vdata; + struct info *p; + + if (data->index >= data->max) + { + fprintf (stderr, "callback_one: callback called too many times\n"); + data->failed = 1; + return 1; + } + + p = &data->all[data->index]; + if (filename == NULL) + p->filename = NULL; + else + { + p->filename = strdup (filename); + assert (p->filename != NULL); + } + p->lineno = lineno; + if (function == NULL) + p->function = NULL; + else + { + p->function = strdup (function); + assert (p->function != NULL); + } + ++data->index; + + return 0; +} + +/* An error callback passed to backtrace. */ + +void +error_callback_one (void *vdata, const char *msg, int errnum) +{ + struct bdata *data = (struct bdata *) vdata; + + fprintf (stderr, "%s", msg); + if (errnum > 0) + fprintf (stderr, ": %s", strerror (errnum)); + fprintf (stderr, "\n"); + data->failed = 1; +} + +/* The backtrace_simple callback function. */ + +int +callback_two (void *vdata, uintptr_t pc) +{ + struct sdata *data = (struct sdata *) vdata; + + if (data->index >= data->max) + { + fprintf (stderr, "callback_two: callback called too many times\n"); + data->failed = 1; + return 1; + } + + data->addrs[data->index] = pc; + ++data->index; + + return 0; +} + +/* An error callback passed to backtrace_simple. */ + +void +error_callback_two (void *vdata, const char *msg, int errnum) +{ + struct sdata *data = (struct sdata *) vdata; + + fprintf (stderr, "%s", msg); + if (errnum > 0) + fprintf (stderr, ": %s", strerror (errnum)); + fprintf (stderr, "\n"); + data->failed = 1; +} + +/* The backtrace_syminfo callback function. */ + +void +callback_three (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, + const char *symname, uintptr_t symval, + uintptr_t symsize) +{ + struct symdata *data = (struct symdata *) vdata; + + if (symname == NULL) + data->name = NULL; + else + { + data->name = strdup (symname); + assert (data->name != NULL); + } + data->val = symval; + data->size = symsize; +} + +/* The backtrace_syminfo error callback function. */ + +void +error_callback_three (void *vdata, const char *msg, int errnum) +{ + struct symdata *data = (struct symdata *) vdata; + + fprintf (stderr, "%s", msg); + if (errnum > 0) + fprintf (stderr, ": %s", strerror (errnum)); + fprintf (stderr, "\n"); + data->failed = 1; +} + +/* The backtrace_create_state error callback function. */ + +void +error_callback_create (void *data ATTRIBUTE_UNUSED, const char *msg, + int errnum) +{ + fprintf (stderr, "%s", msg); + if (errnum > 0) + fprintf (stderr, ": %s", strerror (errnum)); + fprintf (stderr, "\n"); + exit (EXIT_FAILURE); +} Index: testlib.h =================================================================== --- testlib.h (revision 0) +++ testlib.h (working copy) @@ -0,0 +1,110 @@ +/* testlib.h -- Header for test functions for libbacktrace library + Copyright (C) 2012-2017 Free Software Foundation, Inc. + Written by Ian Lance Taylor, Google. + +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. */ + +#ifndef LIBBACKTRACE_TESTLIB_H +#define LIBBACKTRACE_TESTLIB_H + +/* Portable attribute syntax. Actually some of these tests probably + won't work if the attributes are not recognized. */ + +#ifndef GCC_VERSION +# define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) +#endif + +#if (GCC_VERSION < 2007) +# define __attribute__(x) +#endif + +#ifndef ATTRIBUTE_UNUSED +# define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) +#endif + +/* Used to collect backtrace info. */ + +struct info +{ + char *filename; + int lineno; + char *function; +}; + +/* Passed to backtrace callback function. */ + +struct bdata +{ + struct info *all; + size_t index; + size_t max; + int failed; +}; + +/* Passed to backtrace_simple callback function. */ + +struct sdata +{ + uintptr_t *addrs; + size_t index; + size_t max; + int failed; +}; + +/* Passed to backtrace_syminfo callback function. */ + +struct symdata +{ + const char *name; + uintptr_t val, size; + int failed; +}; + +/* The backtrace state. */ + +extern void *state; + +/* The number of failures. */ + +extern int failures; + +extern const char *base (const char *p); +extern void check (const char *name, int index, const struct info *all, + int want_lineno, const char *want_function, + const char *want_file, int *failed); +extern int callback_one (void *, uintptr_t, const char *, int, const char *); +extern void error_callback_one (void *, const char *, int); +extern int callback_two (void *, uintptr_t); +extern void error_callback_two (void *, const char *, int); +extern void callback_three (void *, uintptr_t, const char *, uintptr_t, + uintptr_t); +extern void error_callback_three (void *, const char *, int); +extern void error_callback_create (void *, const char *, int); + +#endif /* !defined(LIBBACKTRACE_TESTLIB_H) */ Index: ttest.c =================================================================== --- ttest.c (revision 0) +++ ttest.c (working copy) @@ -0,0 +1,161 @@ +/* ttest.c -- Test for libbacktrace library + Copyright (C) 2017 Free Software Foundation, Inc. + Written by Ian Lance Taylor, Google. + +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. */ + +/* Test using the libbacktrace library from multiple threads. */ + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <pthread.h> + +#include "filenames.h" + +#include "backtrace.h" +#include "backtrace-supported.h" + +#include "testlib.h" + +static int f2 (int) __attribute__ ((noinline)); +static int f3 (int, int) __attribute__ ((noinline)); + +/* Test that a simple backtrace works. This is called via + pthread_create. It returns the number of failures, as void *. */ + +static void * +test1_thread (void *arg ATTRIBUTE_UNUSED) +{ + /* Returning a value here and elsewhere avoids a tailcall which + would mess up the backtrace. */ + return (void *) (uintptr_t) (f2 (__LINE__) - 2); +} + +static int +f2 (int f1line) +{ + return f3 (f1line, __LINE__) + 2; +} + +static int +f3 (int f1line, int f2line) +{ + struct info all[20]; + struct bdata data; + int f3line; + int i; + + data.all = &all[0]; + data.index = 0; + data.max = 20; + data.failed = 0; + + f3line = __LINE__ + 1; + i = backtrace_full (state, 0, callback_one, error_callback_one, &data); + + if (i != 0) + { + fprintf (stderr, "test1: unexpected return value %d\n", i); + data.failed = 1; + } + + if (data.index < 3) + { + fprintf (stderr, + "test1: not enough frames; got %zu, expected at least 3\n", + data.index); + data.failed = 1; + } + + check ("test1", 0, all, f3line, "f3", "ttest.c", &data.failed); + check ("test1", 1, all, f2line, "f2", "ttest.c", &data.failed); + check ("test1", 2, all, f1line, "test1_thread", "ttest.c", &data.failed); + + return data.failed; +} + +/* Run the test with 10 threads simultaneously. */ + +#define THREAD_COUNT 10 + +static void test1 (void) __attribute__ ((unused)); + +static void +test1 (void) +{ + pthread_t atid[THREAD_COUNT]; + int i; + int errnum; + int this_fail; + void *ret; + + for (i = 0; i < THREAD_COUNT; i++) + { + errnum = pthread_create (&atid[i], NULL, test1_thread, NULL); + if (errnum != 0) + { + fprintf (stderr, "pthread_create %d: %s\n", i, strerror (errnum)); + exit (EXIT_FAILURE); + } + } + + this_fail = 0; + for (i = 0; i < THREAD_COUNT; i++) + { + errnum = pthread_join (atid[i], &ret); + if (errnum != 0) + { + fprintf (stderr, "pthread_join %d: %s\n", i, strerror (errnum)); + exit (EXIT_FAILURE); + } + this_fail += (int) (uintptr_t) ret; + } + + printf ("%s: threaded backtrace_full noinline\n", this_fail > 0 ? "FAIL" : "PASS"); + + failures += this_fail; +} + +int +main (int argc ATTRIBUTE_UNUSED, char **argv) +{ + state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS, + error_callback_create, NULL); + +#if BACKTRACE_SUPPORTED +#if BACKTRACE_SUPPORTS_THREADS + test1 (); +#endif +#endif + + exit (failures ? EXIT_FAILURE : EXIT_SUCCESS); +}