1 files changed, 130 insertions, 0 deletions
diff --git a/libbacktrace/BacktraceMap.cpp b/libbacktrace/BacktraceMap.cpp
new file mode 100644
index 0000000..b3b4300
--- /dev/null
+++ b/libbacktrace/BacktraceMap.cpp
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+#include <ctype.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <string>
+#include <vector>
+
+#include <backtrace/BacktraceMap.h>
+#include <log/log.h>
+
+BacktraceMap::BacktraceMap(pid_t pid) : pid_(pid) {
+  if (pid_ < 0) {
+    pid_ = getpid();
+  }
+}
+
+BacktraceMap::~BacktraceMap() {
+}
+
+const backtrace_map_t* BacktraceMap::Find(uintptr_t addr) {
+  for (BacktraceMap::const_iterator it = begin();
+       it != end(); ++it) {
+    if (addr >= it->start && addr < it->end) {
+      return &*it;
+    }
+  }
+  return NULL;
+}
+
+bool BacktraceMap::ParseLine(const char* line, backtrace_map_t* map) {
+  unsigned long int start;
+  unsigned long int end;
+  char permissions[5];
+  int name_pos;
+
+#if defined(__APPLE__)
+// Mac OS vmmap(1) output:
+// __TEXT                 0009f000-000a1000 [    8K     8K] r-x/rwx SM=COW  /Volumes/android/dalvik-dev/out/host/darwin-x86/bin/libcorkscrew_test\n
+// 012345678901234567890123456789012345678901234567890123456789
+// 0         1         2         3         4         5
+  if (sscanf(line, "%*21c %lx-%lx [%*13c] %3c/%*3c SM=%*3c  %n",
+             &start, &end, permissions, &name_pos) != 3) {
+#else
+// Linux /proc/<pid>/maps lines:
+// 6f000000-6f01e000 rwxp 00000000 00:0c 16389419   /system/lib/libcomposer.so\n
+// 012345678901234567890123456789012345678901234567890123456789
+// 0         1         2         3         4         5
+  if (sscanf(line, "%lx-%lx %4s %*x %*x:%*x %*d%n",
+             &start, &end, permissions, &name_pos) != 3) {
+#endif
+    return false;
+  }
+
+  map->start = start;
+  map->end = end;
+  map->flags = PROT_NONE;
+  if (permissions[0] == 'r') {
+    map->flags |= PROT_READ;
+  }
+  if (permissions[1] == 'w') {
+    map->flags |= PROT_WRITE;
+  }
+  if (permissions[2] == 'x') {
+    map->flags |= PROT_EXEC;
+  }
+
+  while (isspace(line[name_pos])) {
+    name_pos += 1;
+  }
+  map->name = line+name_pos;
+  if (!map->name.empty() && map->name[map->name.length()-1] == '\n') {
+    map->name.erase(map->name.length()-1);
+  }
+
+  ALOGV("Parsed map: start=%p, end=%p, flags=%x, name=%s",
+        map->start, map->end, map->flags, map->name.c_str());
+  return true;
+}
+
+bool BacktraceMap::Build() {
+#if defined(__APPLE__)
+  char cmd[sizeof(pid_t)*3 + sizeof("vmmap -w -resident -submap -allSplitLibs -interleaved ") + 1];
+#else
+  char path[sizeof(pid_t)*3 + sizeof("/proc//maps") + 1];
+#endif
+  char line[1024];
+
+#if defined(__APPLE__)
+  // cmd is guaranteed to always be big enough to hold this string.
+  sprintf(cmd, "vmmap -w -resident -submap -allSplitLibs -interleaved %d", pid);
+  FILE* fp = popen(cmd, "r");
+#else
+  // path is guaranteed to always be big enough to hold this string.
+  sprintf(path, "/proc/%d/maps", pid_);
+  FILE* fp = fopen(path, "r");
+#endif
+  if (fp == NULL) {
+    return false;
+  }
+
+  while(fgets(line, sizeof(line), fp)) {
+    backtrace_map_t map;
+    if (ParseLine(line, &map)) {
+      maps_.push_back(map);
+    }
+  }
+#if defined(__APPLE__)
+  pclose(fp);
+#else
+  fclose(fp);
+#endif
+
+  return true;
+}