[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, 11 insertions, 11 deletions

diff --git a/lib/scudo/standalone/primary32.h b/lib/scudo/standalone/primary32.h
index a9fbb70bc..9123d07b4 100644
--- a/lib/scudo/standalone/primary32.h
+++ b/lib/scudo/standalone/primary32.h
@@ -143,7 +143,7 @@ public:
       }
   }
 
-  void printStats() {
+  void getStats(ScopedString *Str) {
     // TODO(kostyak): get the RSS per region.
     uptr TotalMapped = 0;
     uptr PoppedBlocks = 0;
@@ -154,11 +154,11 @@ public:
       PoppedBlocks += Sci->Stats.PoppedBlocks;
       PushedBlocks += Sci->Stats.PushedBlocks;
     }
-    Printf("Stats: SizeClassAllocator32: %zuM mapped in %zu allocations; "
-           "remains %zu\n",
-           TotalMapped >> 20, PoppedBlocks, PoppedBlocks - PushedBlocks);
+    Str->append("Stats: SizeClassAllocator32: %zuM mapped in %zu allocations; "
+                "remains %zu\n",
+                TotalMapped >> 20, PoppedBlocks, PoppedBlocks - PushedBlocks);
     for (uptr I = 0; I < NumClasses; I++)
-      printStats(I, 0);
+      getStats(Str, I, 0);
   }
 
   uptr releaseToOS() {
@@ -328,17 +328,17 @@ private:
     return B;
   }
 
-  void printStats(uptr ClassId, uptr Rss) {
+  void getStats(ScopedString *Str, uptr ClassId, uptr Rss) {
     SizeClassInfo *Sci = getSizeClassInfo(ClassId);
     if (Sci->AllocatedUser == 0)
       return;
     const uptr InUse = Sci->Stats.PoppedBlocks - Sci->Stats.PushedBlocks;
     const uptr AvailableChunks = Sci->AllocatedUser / getSizeByClassId(ClassId);
-    Printf("  %02zu (%6zu): mapped: %6zuK popped: %7zu pushed: %7zu inuse: %6zu"
-           " avail: %6zu rss: %6zuK\n",
-           ClassId, getSizeByClassId(ClassId), Sci->AllocatedUser >> 10,
-           Sci->Stats.PoppedBlocks, Sci->Stats.PushedBlocks, InUse,
-           AvailableChunks, Rss >> 10);
+    Str->append("  %02zu (%6zu): mapped: %6zuK popped: %7zu pushed: %7zu "
+                "inuse: %6zu avail: %6zu rss: %6zuK\n",
+                ClassId, getSizeByClassId(ClassId), Sci->AllocatedUser >> 10,
+                Sci->Stats.PoppedBlocks, Sci->Stats.PushedBlocks, InUse,
+                AvailableChunks, Rss >> 10);
   }
 
   NOINLINE uptr releaseToOSMaybe(SizeClassInfo *Sci, uptr ClassId,