Allow getting an uncached process map.

(cherry picked from commit f02593b0e61f8108449770094caa7bb39a646ec1)

Change-Id: I2012bf2dc553ebc663345b9eac6d794e80df9c00

2 files changed, 10 insertions, 3 deletions

diff --git a/include/backtrace/BacktraceMap.h b/include/backtrace/BacktraceMap.h
index c717f09..4ed23a8 100644
--- a/include/backtrace/BacktraceMap.h
+++ b/include/backtrace/BacktraceMap.h
@@ -41,7 +41,10 @@ struct backtrace_map_t {
 
 class BacktraceMap {
 public:
-  static BacktraceMap* Create(pid_t pid);
+  // If uncached is true, then parse the current process map as of the call.
+  // Passing a map created with uncached set to true to Backtrace::Create()
+  // is unsupported.
+  static BacktraceMap* Create(pid_t pid, bool uncached = false);
 
   virtual ~BacktraceMap();
 
diff --git a/libbacktrace/UnwindMap.cpp b/libbacktrace/UnwindMap.cpp
index 4f9831b..387d768 100644
--- a/libbacktrace/UnwindMap.cpp
+++ b/libbacktrace/UnwindMap.cpp
@@ -130,9 +130,13 @@ const backtrace_map_t* UnwindMapLocal::Find(uintptr_t addr) {
 //-------------------------------------------------------------------------
 // BacktraceMap create function.
 //-------------------------------------------------------------------------
-BacktraceMap* BacktraceMap::Create(pid_t pid) {
+BacktraceMap* BacktraceMap::Create(pid_t pid, bool uncached) {
   BacktraceMap* map;
-  if (pid == getpid()) {
+
+  if (uncached) {
+    // Force use of the base class to parse the maps when this call is made.
+    map = new BacktraceMap(pid);
+  } else if (pid == getpid()) {
     map = new UnwindMapLocal();
   } else {
     map = new UnwindMap(pid);