diff --git a/include/utils/CallStack.h b/include/utils/CallStack.h
index 61dc832..2056751 100644
--- a/include/utils/CallStack.h
+++ b/include/utils/CallStack.h
@@ -17,50 +17,72 @@
 #ifndef ANDROID_CALLSTACK_H
 #define ANDROID_CALLSTACK_H
 
-#include <stdint.h>
-#include <sys/types.h>
-
+#include <android/log.h>
 #include <utils/String8.h>
 #include <corkscrew/backtrace.h>
 
-// ---------------------------------------------------------------------------
+#include <stdint.h>
+#include <sys/types.h>
 
 namespace android {
 
-class CallStack
-{
+class Printer;
+
+// Collect/print the call stack (function, file, line) traces for a single thread.
+class CallStack {
 public:
     enum {
-        MAX_DEPTH = 31
+        // Prune the lowest-most stack frames until we have at most MAX_DEPTH.
+        MAX_DEPTH = 31,
+        // Placeholder for specifying the current thread when updating the stack.
+        CURRENT_THREAD = -1,
     };
 
+    // Create an empty call stack. No-op.
     CallStack();
+    // Create a callstack with the current thread's stack trace.
+    // Immediately dump it to logcat using the given logtag.
     CallStack(const char* logtag, int32_t ignoreDepth=1,
             int32_t maxDepth=MAX_DEPTH);
+    // Copy the existing callstack (no other side effects).
     CallStack(const CallStack& rhs);
     ~CallStack();
 
+    // Copy the existing callstack (no other side effects).
     CallStack& operator = (const CallStack& rhs);
-    
+
+    // Compare call stacks by their backtrace frame memory.
     bool operator == (const CallStack& rhs) const;
     bool operator != (const CallStack& rhs) const;
     bool operator < (const CallStack& rhs) const;
     bool operator >= (const CallStack& rhs) const;
     bool operator > (const CallStack& rhs) const;
     bool operator <= (const CallStack& rhs) const;
-    
+
+    // Get the PC address for the stack frame specified by index.
     const void* operator [] (int index) const;
-    
+
+    // Reset the stack frames (same as creating an empty call stack).
     void clear();
 
-    void update(int32_t ignoreDepth=1, int32_t maxDepth=MAX_DEPTH);
+    // Immediately collect the stack traces for the specified thread.
+    void update(int32_t ignoreDepth=1, int32_t maxDepth=MAX_DEPTH, pid_t tid=CURRENT_THREAD);
 
-    // Dump a stack trace to the log using the supplied logtag
-    void dump(const char* logtag, const char* prefix = 0) const;
+    // Dump a stack trace to the log using the supplied logtag.
+    void log(const char* logtag,
+             android_LogPriority priority = ANDROID_LOG_DEBUG,
+             const char* prefix = 0) const;
 
-    // Return a string (possibly very long) containing the complete stack trace
+    // Dump a stack trace to the specified file descriptor.
+    void dump(int fd, int indent = 0, const char* prefix = 0) const;
+
+    // Return a string (possibly very long) containing the complete stack trace.
     String8 toString(const char* prefix = 0) const;
-    
+
+    // Dump a serialized representation of the stack trace to the specified printer.
+    void print(Printer& printer) const;
+
+    // Get the count of stack frames that are in this call stack.
     size_t size() const { return mCount; }
 
 private:
@@ -70,7 +92,4 @@
 
 }; // namespace android
 
-
-// ---------------------------------------------------------------------------
-
 #endif // ANDROID_CALLSTACK_H
diff --git a/include/utils/Printer.h b/include/utils/Printer.h
new file mode 100644
index 0000000..bb66287
--- /dev/null
+++ b/include/utils/Printer.h
@@ -0,0 +1,119 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_PRINTER_H
+#define ANDROID_PRINTER_H
+
+#include <android/log.h>
+
+namespace android {
+
+// Interface for printing to an arbitrary data stream
+class Printer {
+public:
+    // Print a new line specified by 'string'. \n is appended automatically.
+    // -- Assumes that the string has no new line in it.
+    virtual void printLine(const char* string = "") = 0;
+
+    // Print a new line specified by the format string. \n is appended automatically.
+    // -- Assumes that the resulting string has no new line in it.
+    virtual void printFormatLine(const char* format, ...) __attribute__((format (printf, 2, 3)));
+
+protected:
+    Printer();
+    virtual ~Printer();
+}; // class Printer
+
+// Print to logcat
+class LogPrinter : public Printer {
+public:
+    // Create a printer using the specified logcat and log priority
+    // - Unless ignoreBlankLines is false, print blank lines to logcat
+    // (Note that the default ALOG behavior is to ignore blank lines)
+    LogPrinter(const char* logtag,
+               android_LogPriority priority = ANDROID_LOG_DEBUG,
+               const char* prefix = 0,
+               bool ignoreBlankLines = false);
+
+    // Print the specified line to logcat. No \n at the end is necessary.
+    virtual void printLine(const char* string);
+
+private:
+    void printRaw(const char* string);
+
+    const char* mLogTag;
+    android_LogPriority mPriority;
+    const char* mPrefix;
+    bool mIgnoreBlankLines;
+}; // class LogPrinter
+
+// Print to a file descriptor
+class FdPrinter : public Printer {
+public:
+    // Create a printer using the specified file descriptor.
+    // - Each line will be prefixed with 'indent' number of blank spaces.
+    // - In addition, each line will be prefixed with the 'prefix' string.
+    FdPrinter(int fd, unsigned int indent = 0, const char* prefix = 0);
+
+    // Print the specified line to the file descriptor. \n is appended automatically.
+    virtual void printLine(const char* string);
+
+private:
+    enum {
+        MAX_FORMAT_STRING = 20,
+    };
+
+    int mFd;
+    unsigned int mIndent;
+    const char* mPrefix;
+    char mFormatString[MAX_FORMAT_STRING];
+}; // class FdPrinter
+
+class String8;
+
+// Print to a String8
+class String8Printer : public Printer {
+public:
+    // Create a printer using the specified String8 as the target.
+    // - In addition, each line will be prefixed with the 'prefix' string.
+    // - target's memory lifetime must be a superset of this String8Printer.
+    String8Printer(String8* target, const char* prefix = 0);
+
+    // Append the specified line to the String8. \n is appended automatically.
+    virtual void printLine(const char* string);
+
+private:
+    String8* mTarget;
+    const char* mPrefix;
+}; // class String8Printer
+
+// Print to an existing Printer by adding a prefix to each line
+class PrefixPrinter : public Printer {
+public:
+    // Create a printer using the specified printer as the target.
+    PrefixPrinter(Printer& printer, const char* prefix);
+
+    // Print the line (prefixed with prefix) using the printer.
+    virtual void printLine(const char* string);
+
+private:
+    Printer& mPrinter;
+    const char* mPrefix;
+};
+
+}; // namespace android
+
+#endif // ANDROID_PRINTER_H
diff --git a/include/utils/ProcessCallStack.h b/include/utils/ProcessCallStack.h
new file mode 100644
index 0000000..4a86869
--- /dev/null
+++ b/include/utils/ProcessCallStack.h
@@ -0,0 +1,79 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_PROCESS_CALLSTACK_H
+#define ANDROID_PROCESS_CALLSTACK_H
+
+#include <utils/CallStack.h>
+#include <android/log.h>
+#include <utils/KeyedVector.h>
+#include <utils/String8.h>
+
+#include <time.h>
+#include <sys/types.h>
+
+namespace android {
+
+class Printer;
+
+// Collect/print the call stack (function, file, line) traces for all threads in a process.
+class ProcessCallStack {
+public:
+    // Create an empty call stack. No-op.
+    ProcessCallStack();
+    // Copy the existing process callstack (no other side effects).
+    ProcessCallStack(const ProcessCallStack& rhs);
+    ~ProcessCallStack();
+
+    // Immediately collect the stack traces for all threads.
+    void update(int32_t maxDepth = CallStack::MAX_DEPTH);
+
+    // Print all stack traces to the log using the supplied logtag.
+    void log(const char* logtag, android_LogPriority priority = ANDROID_LOG_DEBUG,
+             const char* prefix = 0) const;
+
+    // Dump all stack traces to the specified file descriptor.
+    void dump(int fd, int indent = 0, const char* prefix = 0) const;
+
+    // Return a string (possibly very long) containing all the stack traces.
+    String8 toString(const char* prefix = 0) const;
+
+    // Dump a serialized representation of all the stack traces to the specified printer.
+    void print(Printer& printer) const;
+
+    // Get the number of threads whose stack traces were collected.
+    size_t size() const;
+
+private:
+    void printInternal(Printer& printer, Printer& csPrinter) const;
+
+    // Reset the process's stack frames and metadata.
+    void clear();
+
+    struct ThreadInfo {
+        CallStack callStack;
+        String8 threadName;
+    };
+
+    // tid -> ThreadInfo
+    KeyedVector<pid_t, ThreadInfo> mThreadMap;
+    // Time that update() was last called
+    struct tm mTimeUpdated;
+};
+
+}; // namespace android
+
+#endif // ANDROID_PROCESS_CALLSTACK_H