1 files changed, 123 insertions, 0 deletions
diff --git a/libbacktrace/unwind_local.c b/libbacktrace/unwind_local.c
new file mode 100644
index 0000000..e0b72d8
--- /dev/null
+++ b/libbacktrace/unwind_local.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "libbacktrace"
+
+#include <string.h>
+
+#include <cutils/log.h>
+#include <backtrace/backtrace.h>
+
+#define UNW_LOCAL_ONLY
+#include <libunwind.h>
+#include <libunwind-ptrace.h>
+
+#include "common.h"
+#include "demangle.h"
+
+static bool local_get_frames(backtrace_t* backtrace) {
+  unw_context_t* context = (unw_context_t*)backtrace->private_data;
+  unw_cursor_t cursor;
+
+  int ret = unw_getcontext(context);
+  if (ret < 0) {
+    ALOGW("local_get_frames: unw_getcontext failed %d\n", ret);
+    return false;
+  }
+
+  ret = unw_init_local(&cursor, context);
+  if (ret < 0) {
+    ALOGW("local_get_frames: unw_init_local failed %d\n", ret);
+    return false;
+  }
+
+  backtrace_frame_data_t* frame;
+  bool returnValue = true;
+  backtrace->num_frames = 0;
+  uintptr_t map_start;
+  do {
+    frame = &backtrace->frames[backtrace->num_frames];
+    frame->stack_size = 0;
+    frame->map_name = NULL;
+    frame->map_offset = 0;
+    frame->proc_name = NULL;
+    frame->proc_offset = 0;
+
+    ret = unw_get_reg(&cursor, UNW_REG_IP, &frame->pc);
+    if (ret < 0) {
+      ALOGW("get_frames: Failed to read IP %d\n", ret);
+      returnValue = false;
+      break;
+    }
+    ret = unw_get_reg(&cursor, UNW_REG_SP, &frame->sp);
+    if (ret < 0) {
+      ALOGW("get_frames: Failed to read IP %d\n", ret);
+      returnValue = false;
+      break;
+    }
+    if (backtrace->num_frames) {
+      backtrace_frame_data_t* prev = &backtrace->frames[backtrace->num_frames-1];
+      prev->stack_size = frame->sp - prev->sp;
+    }
+
+    frame->proc_name = backtrace_get_proc_name(backtrace, frame->pc, &frame->proc_offset);
+
+    frame->map_name = backtrace_get_map_info(backtrace, frame->pc, &map_start);
+    if (frame->map_name) {
+      frame->map_offset = frame->pc - map_start;
+    }
+
+    backtrace->num_frames++;
+    ret = unw_step (&cursor);
+  } while (ret > 0 && backtrace->num_frames < MAX_BACKTRACE_FRAMES);
+
+  return returnValue;
+}
+
+bool local_get_data(backtrace_t* backtrace) {
+  unw_context_t *context = (unw_context_t*)malloc(sizeof(unw_context_t));
+  backtrace->private_data = context;
+
+  if (!local_get_frames(backtrace)) {
+    backtrace_free_data(backtrace);
+    return false;
+  }
+
+  return true;
+}
+
+void local_free_data(backtrace_t* backtrace) {
+  if (backtrace->private_data) {
+    free(backtrace->private_data);
+    backtrace->private_data = NULL;
+  }
+}
+
+char* local_get_proc_name(const backtrace_t* backtrace, uintptr_t pc,
+                          uintptr_t* offset) {
+  unw_context_t* context = (unw_context_t*)backtrace->private_data;
+  char buf[512];
+
+  if (unw_get_proc_name_by_ip(unw_local_addr_space, pc, buf, sizeof(buf),
+                              offset, context) >= 0 && buf[0] != '\0') {
+    char* symbol = demangle_symbol_name(buf);
+    if (!symbol) {
+      symbol = strdup(buf);
+    }
+    return symbol;
+  }
+  return NULL;
+}