Refactor, add O_TRUNC for opening file.sandbox/mkashkarov/lsan_periodical_check_v2

Change-Id: I5b8f9f47bbc1f2bc477a603873f045615ef14334

2 files changed, 17 insertions, 16 deletions

diff --git a/libsanitizer/lsan/lsan_common.cc b/libsanitizer/lsan/lsan_common.cc
index e8a72b9f34c..5b9cf9b9312 100644
--- a/libsanitizer/lsan/lsan_common.cc
+++ b/libsanitizer/lsan/lsan_common.cc
@@ -490,6 +490,12 @@ static bool CheckForLeaks() {
   return false;
 }
 
+void MaybeRestoreLogPath() {
+  if (flags()->periodically_check_leaks ||
+      flags()->periodically_check_leaks_interval_ms)
+    __sanitizer_set_report_path(common_flags()->log_path);
+}
+
 void DoLeakCheck() {
   VReport(2, "[LSAN] DoLeakCheck\n");
   BlockingMutexLock l(&global_mutex);
@@ -497,9 +503,7 @@ void DoLeakCheck() {
   if (already_done) return;
   already_done = true;
   // Log path is modified if periodically checking for leaks
-  if (flags()->periodically_check_leaks ||
-      flags()->periodically_check_leaks_interval_ms)
-  __sanitizer_set_report_path(common_flags()->log_path);
+  MaybeRestoreLogPath();
   bool have_leaks = CheckForLeaks();
   if (!have_leaks) {
     return;
@@ -520,23 +524,20 @@ void DoRecoverableLeakCheckVoid() {
   DoRecoverableLeakCheck();
 }
 
-void LogPathAppend(const char* suffix) {
-  if (!common_flags()->log_path) return;
+void MaybeAppendLogPath(const char* suffix) {
+  const char* log_path = common_flags()->log_path;
+  if (!log_path) return;
+  if ((internal_strcmp(log_path, "stderr") == 0) ||
+      (internal_strcmp(log_path, "stdout") == 0)) return;
+
   char new_log_path[kMaxPathLength];
-  internal_strlcat(new_log_path, common_flags()->log_path, kMaxPathLength);
-  internal_strlcat(new_log_path, suffix, kMaxPathLength);
-  __sanitizer_set_report_path(log_path_in_progress);
+  internal_snprintf(new_log_path, kMaxPathLength, "%s.%s", log_path, suffix);
+  __sanitizer_set_report_path(new_log_path);
 }
 
 void BackgroudLeakCheckingThread(void *arg) {
   s32 interval_ms = flags()->periodically_check_leaks_interval_ms;
-  // Append suffix to indicate leaks from this thread
-  char log_path_in_progress[kMaxPathLength];
-  const char* log_path_prefix = "-in-progress";
-  internal_strlcat(log_path_in_progress, common_flags()->log_path, sizeof(log_path_in_progress));
-  internal_strlcat(log_path_in_progress, log_path_prefix,  sizeof(log_path_in_progress));
-  __sanitizer_set_report_path(log_path_in_progress);
-  // LogPathAppend()
+  MaybeAppendLogPath("in-progress");
   while (true) {
     SleepForMillis(interval_ms);
     if (!lsan_check_in_progress)
diff --git a/libsanitizer/sanitizer_common/sanitizer_posix.cc b/libsanitizer/sanitizer_common/sanitizer_posix.cc
index eccbdf6b1fd..1a24cb60d58 100644
--- a/libsanitizer/sanitizer_common/sanitizer_posix.cc
+++ b/libsanitizer/sanitizer_common/sanitizer_posix.cc
@@ -208,7 +208,7 @@ fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *errno_p) {
   int flags;
   switch (mode) {
     case RdOnly: flags = O_RDONLY; break;
-    case WrOnly: flags = O_WRONLY | O_CREAT; break;
+    case WrOnly: flags = O_WRONLY | O_CREAT | O_TRUNC; break;
     case RdWr: flags = O_RDWR | O_CREAT; break;
   }
   fd_t res = internal_open(filename, flags, 0660);