Copy in libbacktrace from gcc

This copies in libbacktrace from the gcc repository as it was in the
commit 62e420293a293608f383d9b9c7f2debd666e9fc9.  GDB is going to
start using this library soon.

A dependency between GDB and libbacktrace has already been added to
the top level Makefile, so, after this commit, when building GDB,
libbacktrace will be built first.  However, libbacktrace is not yet
linked into GDB, or used by GDB in any way.

It is possible to stop libbacktrace being built by configuring the
tree with --disable-libbacktrace.

This commit does NOT update src-release.sh, that will be done in the
next commit, this commit ONLY imports libbacktrace from gcc.  This
means that if you try to make a release of GDB from exactly this
commit then the release tar file will not include libbacktrace.
However, as libbacktrace is an optional dependency this is fine.

1 files changed, 501 insertions, 0 deletions

diff --git a/libbacktrace/btest.c b/libbacktrace/btest.c
new file mode 100644
index 0000000..9f9c03b
--- /dev/null
+++ b/libbacktrace/btest.c
@@ -0,0 +1,501 @@
+/* btest.c -- Test for libbacktrace library
+   Copyright (C) 2012-2021 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.  */
+
+/* This program tests the externally visible interfaces of the
+   libbacktrace library.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+/* Test the backtrace function with non-inlined functions.  */
+
+static int test1 (void) __attribute__ ((noinline, noclone, unused));
+static int f2 (int) __attribute__ ((noinline, noclone));
+static int f3 (int, int) __attribute__ ((noinline, noclone));
+
+static int
+test1 (void)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return f2 (__LINE__) + 1;
+}
+
+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", "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");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace function with inlined functions.  */
+
+static inline int test2 (void) __attribute__ ((always_inline, unused));
+static inline int f12 (int) __attribute__ ((always_inline));
+static inline int f13 (int, int) __attribute__ ((always_inline));
+
+static inline int
+test2 (void)
+{
+  return f12 (__LINE__) + 1;
+}
+
+static inline int
+f12 (int f1line)
+{
+  return f13 (f1line, __LINE__) + 2;
+}
+
+static inline int
+f13 (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, "test2: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  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");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace_simple function with non-inlined functions.  */
+
+static int test3 (void) __attribute__ ((noinline, noclone, unused));
+static int f22 (int) __attribute__ ((noinline, noclone));
+static int f23 (int, int) __attribute__ ((noinline, noclone));
+
+static int
+test3 (void)
+{
+  return f22 (__LINE__) + 1;
+}
+
+static int
+f22 (int f1line)
+{
+  return f23 (f1line, __LINE__) + 2;
+}
+
+static int
+f23 (int f1line, int f2line)
+{
+  uintptr_t addrs[20];
+  struct sdata data;
+  int f3line;
+  int i;
+
+  data.addrs = &addrs[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_simple (state, 0, callback_two, error_callback_two, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test3: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (!data.failed)
+    {
+      struct info all[20];
+      struct bdata bdata;
+      int j;
+
+      bdata.all = &all[0];
+      bdata.index = 0;
+      bdata.max = 20;
+      bdata.failed = 0;
+
+      for (j = 0; j < 3; ++j)
+	{
+	  i = backtrace_pcinfo (state, addrs[j], callback_one,
+				error_callback_one, &bdata);
+	  if (i != 0)
+	    {
+	      fprintf (stderr,
+		       ("test3: unexpected return value "
+			"from backtrace_pcinfo %d\n"),
+		       i);
+	      bdata.failed = 1;
+	    }
+	  if (!bdata.failed && bdata.index != (size_t) (j + 1))
+	    {
+	      fprintf (stderr,
+		       ("wrong number of calls from backtrace_pcinfo "
+			"got %u expected %d\n"),
+		       (unsigned int) bdata.index, j + 1);
+	      bdata.failed = 1;
+	    }
+	}
+
+      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;
+
+      for (j = 0; j < 3; ++j)
+	{
+	  struct symdata symdata;
+
+	  symdata.name = NULL;
+	  symdata.val = 0;
+	  symdata.size = 0;
+	  symdata.failed = 0;
+
+	  i = backtrace_syminfo (state, addrs[j], callback_three,
+				 error_callback_three, &symdata);
+	  if (i == 0)
+	    {
+	      fprintf (stderr,
+		       ("test3: [%d]: unexpected return value "
+			"from backtrace_syminfo %d\n"),
+		       j, i);
+	      symdata.failed = 1;
+	    }
+
+	  if (!symdata.failed)
+	    {
+	      const char *expected;
+
+	      switch (j)
+		{
+		case 0:
+		  expected = "f23";
+		  break;
+		case 1:
+		  expected = "f22";
+		  break;
+		case 2:
+		  expected = "test3";
+		  break;
+		default:
+		  assert (0);
+		}
+
+	      if (symdata.name == NULL)
+		{
+		  fprintf (stderr, "test3: [%d]: NULL syminfo name\n", j);
+		  symdata.failed = 1;
+		}
+	      /* Use strncmp, not strcmp, because GCC might create a
+		 clone.  */
+	      else if (strncmp (symdata.name, expected, strlen (expected))
+		       != 0)
+		{
+		  fprintf (stderr,
+			   ("test3: [%d]: unexpected syminfo name "
+			    "got %s expected %s\n"),
+			   j, symdata.name, expected);
+		  symdata.failed = 1;
+		}
+	    }
+
+	  if (symdata.failed)
+	    data.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_simple noinline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace_simple function with inlined functions.  */
+
+static inline int test4 (void) __attribute__ ((always_inline, unused));
+static inline int f32 (int) __attribute__ ((always_inline));
+static inline int f33 (int, int) __attribute__ ((always_inline));
+
+static inline int
+test4 (void)
+{
+  return f32 (__LINE__) + 1;
+}
+
+static inline int
+f32 (int f1line)
+{
+  return f33 (f1line, __LINE__) + 2;
+}
+
+static inline int
+f33 (int f1line, int f2line)
+{
+  uintptr_t addrs[20];
+  struct sdata data;
+  int f3line;
+  int i;
+
+  data.addrs = &addrs[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_simple (state, 0, callback_two, error_callback_two, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test3: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (!data.failed)
+    {
+      struct info all[20];
+      struct bdata bdata;
+
+      bdata.all = &all[0];
+      bdata.index = 0;
+      bdata.max = 20;
+      bdata.failed = 0;
+
+      i = backtrace_pcinfo (state, addrs[0], callback_one, error_callback_one,
+			    &bdata);
+      if (i != 0)
+	{
+	  fprintf (stderr,
+		   ("test4: unexpected return value "
+		    "from backtrace_pcinfo %d\n"),
+		   i);
+	  bdata.failed = 1;
+	}
+
+      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;
+    }
+
+  printf ("%s: backtrace_simple inline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+static int test5 (void) __attribute__ ((unused));
+
+int global = 1;
+
+static int
+test5 (void)
+{
+  struct symdata symdata;
+  int i;
+  uintptr_t addr = (uintptr_t) &global;
+
+  if (sizeof (global) > 1)
+    addr += 1;
+
+  symdata.name = NULL;
+  symdata.val = 0;
+  symdata.size = 0;
+  symdata.failed = 0;
+
+  i = backtrace_syminfo (state, addr, callback_three,
+			 error_callback_three, &symdata);
+  if (i == 0)
+    {
+      fprintf (stderr,
+	       "test5: unexpected return value from backtrace_syminfo %d\n",
+	       i);
+      symdata.failed = 1;
+    }
+
+  if (!symdata.failed)
+    {
+      if (symdata.name == NULL)
+	{
+	  fprintf (stderr, "test5: NULL syminfo name\n");
+	  symdata.failed = 1;
+	}
+      else if (!(strncmp (symdata.name, "global", 6) == 0
+		 && (symdata.name[6] == '\0'|| symdata.name[6] == '.')))
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo name got %s expected %s\n",
+		   symdata.name, "global");
+	  symdata.failed = 1;
+	}
+      else if (symdata.val != (uintptr_t) &global)
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo value got %lx expected %lx\n",
+		   (unsigned long) symdata.val,
+		   (unsigned long) (uintptr_t) &global);
+	  symdata.failed = 1;
+	}
+      else if (symdata.size != sizeof (global))
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo size got %lx expected %lx\n",
+		   (unsigned long) symdata.size,
+		   (unsigned long) sizeof (global));
+	  symdata.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_syminfo variable\n",
+	  symdata.failed ? "FAIL" : "PASS");
+
+  if (symdata.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Check that are no files left open.  */
+
+static void
+check_open_files (void)
+{
+  int i;
+
+  for (i = 3; i < 10; i++)
+    {
+      if (close (i) == 0)
+	{
+	  fprintf (stderr,
+		   "ERROR: descriptor %d still open after tests complete\n",
+		   i);
+	  ++failures;
+	}
+    }
+}
+
+/* Run all the tests.  */
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+#if BACKTRACE_SUPPORTED
+  test1 ();
+  test2 ();
+  test3 ();
+  test4 ();
+#if BACKTRACE_SUPPORTS_DATA
+  test5 ();
+#endif
+#endif
+
+  check_open_files ();
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}