1 files changed, 129 insertions, 0 deletions
diff --git a/libbacktrace/backtrace.c b/libbacktrace/backtrace.c
new file mode 100644
index 0000000..7b62900
--- /dev/null
+++ b/libbacktrace/backtrace.c
@@ -0,0 +1,129 @@
+/* backtrace.c -- Entry point for stack backtrace 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.  */
+
+#include "config.h"
+
+#include <sys/types.h>
+
+#include "unwind.h"
+#include "backtrace.h"
+#include "internal.h"
+
+/* The main backtrace_full routine.  */
+
+/* Data passed through _Unwind_Backtrace.  */
+
+struct backtrace_data
+{
+  /* Number of frames to skip.  */
+  int skip;
+  /* Library state.  */
+  struct backtrace_state *state;
+  /* Callback routine.  */
+  backtrace_full_callback callback;
+  /* Error callback routine.  */
+  backtrace_error_callback error_callback;
+  /* Data to pass to callback routines.  */
+  void *data;
+  /* Value to return from backtrace_full.  */
+  int ret;
+  /* Whether there is any memory available.  */
+  int can_alloc;
+};
+
+/* Unwind library callback routine.  This is passed to
+   _Unwind_Backtrace.  */
+
+static _Unwind_Reason_Code
+unwind (struct _Unwind_Context *context, void *vdata)
+{
+  struct backtrace_data *bdata = (struct backtrace_data *) vdata;
+  uintptr_t pc;
+  int ip_before_insn = 0;
+
+#ifdef HAVE_GETIPINFO
+  pc = _Unwind_GetIPInfo (context, &ip_before_insn);
+#else
+  pc = _Unwind_GetIP (context);
+#endif
+
+  if (bdata->skip > 0)
+    {
+      --bdata->skip;
+      return _URC_NO_REASON;
+    }
+
+  if (!ip_before_insn)
+    --pc;
+
+  if (!bdata->can_alloc)
+    bdata->ret = bdata->callback (bdata->data, pc, NULL, 0, NULL);
+  else
+    bdata->ret = backtrace_pcinfo (bdata->state, pc, bdata->callback,
+				   bdata->error_callback, bdata->data);
+  if (bdata->ret != 0)
+    return _URC_END_OF_STACK;
+
+  return _URC_NO_REASON;
+}
+
+/* Get a stack backtrace.  */
+
+int __attribute__((noinline))
+backtrace_full (struct backtrace_state *state, int skip,
+		backtrace_full_callback callback,
+		backtrace_error_callback error_callback, void *data)
+{
+  struct backtrace_data bdata;
+  void *p;
+
+  bdata.skip = skip + 1;
+  bdata.state = state;
+  bdata.callback = callback;
+  bdata.error_callback = error_callback;
+  bdata.data = data;
+  bdata.ret = 0;
+
+  /* If we can't allocate any memory at all, don't try to produce
+     file/line information.  */
+  p = backtrace_alloc (state, 4096, NULL, NULL);
+  if (p == NULL)
+    bdata.can_alloc = 0;
+  else
+    {
+      backtrace_free (state, p, 4096, NULL, NULL);
+      bdata.can_alloc = 1;
+    }
+
+  _Unwind_Backtrace (unwind, &bdata);
+  return bdata.ret;
+}