test: Add a test like test-mem, but using reg_states_iterate to find the state and

apply_reg_state to use it to complete the unw_step.

tests/Makefile.am

@@ -47,8 +47,8 @@ endif #!ARCH_IA64
 			Gtest-trace Ltest-trace				 \
 			Ltest-init-local-signal				 \
 			test-async-sig test-flush-cache test-init-remote \
-			test-mem Ltest-varargs Ltest-nomalloc	 \
-			Ltest-nocalloc Lrs-race
+			test-mem test-reg-state Ltest-varargs		 \
+			Ltest-nomalloc Ltest-nocalloc Lrs-race
  noinst_PROGRAMS_cdep += forker Gperf-simple Lperf-simple \
 			Gperf-trace Lperf-trace
 
@@ -171,6 +171,7 @@ test_async_sig_LDADD = $(LIBUNWIND_local) -lpthread
 test_flush_cache_LDADD = $(LIBUNWIND_local)
 test_init_remote_LDADD = $(LIBUNWIND) $(LIBUNWIND_local)
 test_mem_LDADD = $(LIBUNWIND) $(LIBUNWIND_local)
+test_reg_state_LDADD = $(LIBUNWIND) $(LIBUNWIND_local)
 test_ptrace_LDADD = $(LIBUNWIND_ptrace) $(LIBUNWIND)
 test_proc_info_LDADD = $(LIBUNWIND)
 test_static_link_LDADD = $(LIBUNWIND)

tests/test-reg-state.c

@@ -0,0 +1,133 @@
+/* libunwind - a platform-independent unwind library
+   Copyright (C) 2003-2004 Hewlett-Packard Co
+	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
+
+This file is part of libunwind.
+
+Copyright (c) 2003 Hewlett-Packard Co.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
+
+#include "compiler.h"
+
+#include <libunwind.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/mman.h>
+#include <sys/resource.h>
+
+#define panic(args...)				\
+	{ fprintf (stderr, args); exit (-1); }
+
+int verbose;
+
+struct cb_data
+{
+  unw_word_t ip;
+  void* reg_state;
+  size_t len;
+};
+
+static int
+dwarf_reg_states_callback(void *token,
+			  void *rs,
+			  size_t size,
+			  unw_word_t start_ip, unw_word_t end_ip)
+{
+  struct cb_data *data = token;
+  if (start_ip <= data->ip && data->ip < end_ip)
+    {
+      data->reg_state = mmap(NULL, size, PROT_READ | PROT_WRITE,
+			     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+      memcpy(data->reg_state, rs, size);
+      data->len = size;
+    }
+  return 0;
+}
+
+static void
+do_backtrace (void)
+{
+  unw_cursor_t cursor;
+  unw_word_t ip, sp;
+  unw_context_t uc;
+  int ret;
+
+  unw_getcontext (&uc);
+  if (unw_init_local (&cursor, &uc) < 0)
+    panic ("unw_init_local failed!\n");
+
+  do
+    {
+      unw_get_reg (&cursor, UNW_REG_IP, &ip);
+      unw_get_reg (&cursor, UNW_REG_SP, &sp);
+
+      if (verbose)
+	printf ("%016lx (sp=%016lx)\n", (long) ip, (long) sp);
+
+      struct cb_data data = {.ip = ip, .reg_state = NULL};
+      ret = unw_reg_states_iterate(&cursor, dwarf_reg_states_callback, &data);
+      if (ret > 0)
+	{
+	  ret = unw_apply_reg_state (&cursor, data.reg_state);
+	  munmap(data.reg_state, data.len);
+	}
+      if (ret < 0)
+	{
+	  unw_get_reg (&cursor, UNW_REG_IP, &ip);
+	  panic ("FAILURE: unw_step() returned %d for ip=%lx\n",
+		 ret, (long) ip);
+	}
+    }
+  while (ret > 0);
+}
+
+int
+consume_some_stack_space (void)
+{
+  unw_cursor_t cursor;
+  unw_context_t uc;
+  char string[1024];
+
+  memset (&cursor, 0, sizeof (cursor));
+  memset (&uc, 0, sizeof (uc));
+  return sprintf (string, "hello %p %p\n", &cursor, &uc);
+}
+
+int
+main (int argc, char **argv UNUSED)
+{
+  struct rlimit rlim;
+
+  verbose = argc > 1;
+
+  if (consume_some_stack_space () > 9999)
+    exit (-1);	/* can't happen, but don't let the compiler know... */
+
+  rlim.rlim_cur = 0;
+  rlim.rlim_max = RLIM_INFINITY;
+  setrlimit (RLIMIT_DATA, &rlim);
+
+  do_backtrace ();
+  return 0;
+}