Change cygprofile to work on Android.

tools/cygprofile/cygprofile.cc

Index: tools/cygprofile/cygprofile.cc
diff --git a/tools/cygprofile/cygprofile.cc b/tools/cygprofile/cygprofile.cc
index 1c4136f9d459a4484daf5acf87d33f7d44f8e9fc..652d489e759fbb493483e8264b6789e67aa92b5d 100644
--- a/tools/cygprofile/cygprofile.cc
+++ b/tools/cygprofile/cygprofile.cc
@@ -32,9 +32,9 @@
 #include <sys/syscall.h>
 #include <sys/time.h>
 #include <sys/types.h>
-#include <unordered_set>
 #include <vector>
 
+#include "base/hash_tables.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/singleton.h"
@@ -131,7 +131,7 @@ class CygTlsLog {
 
   // Keeps track of all functions that have been logged on this thread
   // so we do not record dublicates.
-  std::unordered_set<void*> functions_called_;
+  std::hash_set<void*> functions_called_;
 
   // Thread identifier as Linux kernel shows it. For debugging purposes.
   // LWP (light-weight process) is a unique ID of the thread in the system,
@@ -152,7 +152,7 @@ struct AllLogs {
 base::LazyInstance<AllLogs>::Leaky all_logs_ = LAZY_INSTANCE_INITIALIZER;
 
 // Per-thread pointer to the current log object.
-__thread CygTlsLog* tls_current_log = NULL;
+static __thread CygTlsLog* tls_current_log = NULL;
 
 // Magic value of above to prevent the instrumentation. Used when CygTlsLog is
 // being constructed (to prevent reentering by malloc, for example) and by
@@ -164,7 +164,12 @@ CygTlsLog* const kMagicBeingConstructed = reinterpret_cast<CygTlsLog*>(1);
 const int CygTlsLog::kBufMaxSize = 3000;
 
 // "cyglog.PID.LWP.pthread_self.PPID"
+#if defined(OS_ANDROID)

[bulach, 2012/12/03 16:48:30]

maybe splitting this would be nicer:

#if defined(OS_ANDROID)
const char CytTlsLog::kLogFileNamePrefix =
"/data/local/tmp/chrome/cyglog/cyglog.";
#else
const char CytTlsLog::kLogFileNamePrefix = "/var/log/chrome/cyglog.";
#endif

const char CygTlsLog::kLogFilenameFmt[] = "%s%d.%d.%ld-%d"

this way if the format changes we'd need to change just one place.. wdyt?

[felipeg, 2012/12/03 16:56:44]

Done.

+const char CygTlsLog::kLogFilenameFmt[] =
+    "/data/local/tmp/chrome/cyglog/cyglog.%d.%d.%ld-%d";
+#else
 const char CygTlsLog::kLogFilenameFmt[] = "/var/log/chrome/cyglog.%d.%d.%ld-%d";
+#endif
 
 CygCommon* CygCommon::GetInstance() {
   return Singleton<CygCommon>::get();
@@ -281,9 +286,12 @@ void CygTlsLog::AddNewLog(CygTlsLog* newlog) {
   AllLogs& all_logs = all_logs_.Get();
   base::AutoLock lock(all_logs.mutex);
   if (all_logs.logs.empty()) {
+
+#if !defined(OS_ANDROID)

[glotov, 2012/12/03 16:42:17]

Could you please make a simple test that verifies that cygprofile still records
all routines in a simple multi-threaded program for OS_ANDROID.

[felipeg, 2012/12/03 16:56:44]

Done.

[glotov, 2012/12/03 17:10:08]

Well, actually it is up to you. Are you 100% sure that android does not use fork
(internally) for creating child processes? If so, please add the comment to your
#if.

Without these hooks child process will produce incorrect log (see comments for
AtForkChild), but you may not notice it at first sight. That's why I would
create a test. What do you think?

[felipeg, 2012/12/03 18:51:20]

I am 100% sure that we don't fork and we will never fork on chrome for android.
See the added comments.
Thanks for the heads up about this issue.

     CHECK(!pthread_atfork(CygTlsLog::AtForkPrepare,
                           CygTlsLog::AtForkParent,
                           CygTlsLog::AtForkChild));
+#endif
 
     // The very first process starts its flush thread here. Forked processes
     // will do it in AtForkChild().
@@ -304,7 +312,6 @@ static void WriteLogLine(int fd, const char* fmt, ...) {
 
 void CygTlsLog::FlushLog() {
   bool first_log_write = false;
-
   if (log_filename_.empty()) {
     first_log_write = true;
     char buf[80];