Enhance native stack dumps.

Provides a new mechanism for dumpstate (while running as root)
to request that debuggerd dump the stacks of native processes that
we care about in bug reports.  In this mode, the backtrace
is formatted to look similar to a Dalvik backtrace.

Moved the tombstone generating code into a separate file to
make it easier to maintain.

Fixed a bug where sometimes the stack traces would be incomplete
because we were not waiting for each thread to stop after issuing
PTRACE_ATTACH, only the main thread.  So sometimes we were missing
traces for some threads.

Refactored the logging code to prevent accidentally writing data
to logcat when explicitly dumping a tombstone or backtrace from the
console.

Only root or system server can request to dump backtraces but
only root can dump tombstones.

Bug: 6615693
Change-Id: Ib3edcc16f9f3a687e414e3f2d250d9500566123b
diff --git a/debuggerd/utility.h b/debuggerd/utility.h
index 39f91cb..136f46d 100644
--- a/debuggerd/utility.h
+++ b/debuggerd/utility.h
@@ -20,53 +20,35 @@
 
 #include <stddef.h>
 #include <stdbool.h>
-#include <sys/types.h>
-#include <corkscrew/backtrace.h>
+
+typedef struct {
+    /* tombstone file descriptor */
+    int tfd;
+    /* if true, does not log anything to the Android logcat */
+    bool quiet;
+} log_t;
 
 /* Log information onto the tombstone. */
-void _LOG(int tfd, bool in_tombstone_only, const char *fmt, ...)
+void _LOG(log_t* log, bool in_tombstone_only, const char *fmt, ...)
         __attribute__ ((format(printf, 3, 4)));
 
-#define LOG(fmt...) _LOG(-1, 0, fmt)
+#define LOG(fmt...) _LOG(NULL, 0, fmt)
 
 /* Set to 1 for normal debug traces */
 #if 0
-#define XLOG(fmt...) _LOG(-1, 0, fmt)
+#define XLOG(fmt...) _LOG(NULL, 0, fmt)
 #else
 #define XLOG(fmt...) do {} while(0)
 #endif
 
 /* Set to 1 for chatty debug traces. Includes all resolved dynamic symbols */
 #if 0
-#define XLOG2(fmt...) _LOG(-1, 0, fmt)
+#define XLOG2(fmt...) _LOG(NULL, 0, fmt)
 #else
 #define XLOG2(fmt...) do {} while(0)
 #endif
 
-/*
- * Returns true if the specified signal has an associated address.
- * (i.e. it sets siginfo_t.si_addr).
- */
-bool signal_has_address(int sig);
-
-/*
- * Dumps the backtrace and contents of the stack.
- */
-void dump_backtrace_and_stack(const ptrace_context_t* context, int tfd, pid_t tid, bool at_fault);
-
-/*
- * Dumps a few bytes of memory, starting a bit before and ending a bit
- * after the specified address.
- */
-void dump_memory(int tfd, pid_t tid, uintptr_t addr, bool at_fault);
-
-/*
- * If this isn't clearly a null pointer dereference, dump the
- * /proc/maps entries near the fault address.
- *
- * This only makes sense to do on the thread that crashed.
- */
-void dump_nearby_maps(const ptrace_context_t* context, int tfd, pid_t tid);
-
+int wait_for_signal(pid_t tid, int* total_sleep_time_usec);
+void wait_for_stop(pid_t tid, int* total_sleep_time_usec);
 
 #endif // _DEBUGGERD_UTILITY_H