Implement /proc/self/maps/ parsing code.

base/debug/proc_maps.cc

Index: base/debug/proc_maps.cc
diff --git a/base/debug/proc_maps.cc b/base/debug/proc_maps.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f478afd59a3c55795864e22045e8a73a76e75dcb
--- /dev/null
+++ b/base/debug/proc_maps.cc
@@ -0,0 +1,66 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/debug/proc_maps.h"
+
+#include <inttypes.h>
+
+#include "base/file_util.h"
+#include "base/strings/string_split.h"
+
+namespace base {
+namespace debug {
+
+#if defined(OS_LINUX) || defined(OS_ANDROID)
+
+std::string ReadProcMaps() {
+  std::string proc_maps;
+  FilePath proc_maps_path("/proc/self/maps");
+  if (!file_util::ReadFileToString(proc_maps_path, &proc_maps))
+    proc_maps.clear();
+  return proc_maps;
+}
+
+void ParseProcMaps(const std::string& input,
+                   std::vector<MappedMemoryRegion>* regions) {
+  // Sample format from man 5 proc:
+  //
+  // address           perms offset  dev   inode   pathname
+  // 08048000-08056000 r-xp 00000000 03:0c 64593   /usr/sbin/gpm
+  //
+  // The final %n term captures the offset in the input string, which is used
+  // to determine the path name.
+  static const char kProcMapFormat[] =

[satorux1, 2013/07/01 03:59:56]

remove static? function-local 'static' is not guaranteed to be thread-safe with
some compilers, IIRC. Maybe simpler to go without a constant:

if (!sscanf("%" SCNxPTR "-%" SCNxPTR " %*s %zx %*x:%*x %*d %n",

[scherkus (not reviewing), 2013/07/01 21:59:45]

Done.

+      "%" SCNxPTR "-%" SCNxPTR " %*s %zx %*x:%*x %*d %n";

[satorux1, 2013/07/01 03:59:56]

didn't know about SCNxPTR. :)

[scherkus (not reviewing), 2013/07/01 21:59:45]

yeah I didn't either until I starting looking through inttypes.h

however android's libc seems to disagree on what a uintptr_t is... will see if
digit@ knows what to make of it

+
+  regions->clear();
+
+  // This isn't async safe nor terribly efficient, but it doesn't need to be at
+  // this point in time.
+  std::vector<std::string> lines;
+  SplitString(input, '\n', &lines);
+
+  for (size_t i = 0; i < lines.size(); ++i) {
+    const char* line = lines[i].c_str();
+    uintptr_t start = 0;
+    uintptr_t end = 0;
+    size_t offset = 0;
+    int path_index = 0;
+
+    if (sscanf(line, kProcMapFormat, &start, &end, &offset, &path_index) < 3)
+      continue;
+
+    MappedMemoryRegion region;
+    region.start = start;
+    region.end = end;
+    region.offset = offset;
+    region.path = FilePath(line + path_index);
+    regions->push_back(region);
+  }
+}
+
+#endif
+
+}  // namespace debug
+}  // namespace base