[scudo][standalone] Get statistics in a char buffer

Summary:
Following up on D68471, this CL introduces some `getStats` APIs to
gather statistics in char buffers (`ScopedString` really) instead of
printing them out right away. Ultimately `printStats` will just
output the buffer, but that allows us to potentially do some work
on the intermediate buffer, and can be used for a `mallocz` type
of functionality. This allows us to pretty much get rid of all the
`Printf` calls around, but I am keeping the function in for
debugging purposes.

This changes the existing tests to use the new APIs when required.

I will add new tests as suggested in D68471 in another CL.

Reviewers: morehouse, hctim, vitalybuka, eugenis, cferris

Reviewed By: morehouse

Subscribers: delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D68653

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@374173 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 10 deletions

diff --git a/lib/scudo/standalone/quarantine.h b/lib/scudo/standalone/quarantine.h
index 732373aba..35fd0bc19 100644
--- a/lib/scudo/standalone/quarantine.h
+++ b/lib/scudo/standalone/quarantine.h
@@ -130,7 +130,7 @@ public:
     subFromSize(ExtractedSize);
   }
 
-  void printStats() const {
+  void getStats(ScopedString *Str) const {
     uptr BatchCount = 0;
     uptr TotalOverheadBytes = 0;
     uptr TotalBytes = 0;
@@ -152,11 +152,11 @@ public:
         (TotalQuarantinedBytes == 0)
             ? 0
             : TotalOverheadBytes * 100 / TotalQuarantinedBytes;
-    Printf("Global quarantine stats: batches: %zu; bytes: %zu (user: %zu); "
-           "chunks: %zu (capacity: %zu); %zu%% chunks used; %zu%% memory "
-           "overhead\n",
-           BatchCount, TotalBytes, TotalQuarantinedBytes, TotalQuarantineChunks,
-           QuarantineChunksCapacity, ChunksUsagePercent, MemoryOverheadPercent);
+    Str->append(
+        "Stats: Quarantine: batches: %zu; bytes: %zu (user: %zu); chunks: %zu "
+        "(capacity: %zu); %zu%% chunks used; %zu%% memory overhead\n",
+        BatchCount, TotalBytes, TotalQuarantinedBytes, TotalQuarantineChunks,
+        QuarantineChunksCapacity, ChunksUsagePercent, MemoryOverheadPercent);
   }
 
 private:
@@ -218,11 +218,11 @@ public:
     recycle(0, Cb);
   }
 
-  void printStats() const {
+  void getStats(ScopedString *Str) const {
     // It assumes that the world is stopped, just as the allocator's printStats.
-    Printf("Quarantine limits: global: %zuM; thread local: %zuK\n",
-           getMaxSize() >> 20, getCacheSize() >> 10);
-    Cache.printStats();
+    Cache.getStats(Str);
+    Str->append("Quarantine limits: global: %zuK; thread local: %zuK\n",
+                getMaxSize() >> 10, getCacheSize() >> 10);
   }
 
 private: