[scudo] Handle mallinfo2

[vitalybuka]

Summary

mallinfo is deprecated by GLIBC

[pcc]

Doesn't this require a wrapper for mallinfo2() as well that returns a struct mallinfo2?

[pcc]

compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp

270

It doesn't look like glibc's headers define a macro named mallinfo2, so this will always be false.

[vitalybuka]

In D113951#3133267, @pcc wrote:

Doesn't this require a wrapper for mallinfo2() as well that returns a struct mallinfo2?

Thanks, it does.

compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp

270

https://github.com/bminor/glibc/blob/cbcd65c8b526555d9b98628338973f91f74002ad/malloc/malloc.h#L99

[vitalybuka]

compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp

270

I mean, you are correct, I need to do something better. Probably check GLIBC version,
It was speculative fix without trying on the bot.

https://lab.llvm.org/staging/#/builders/97/builds/560/steps/37/logs/stdio

[vitalybuka]

handle mallinfo2

[cryptoad]

compiler-rt/lib/scudo/standalone/wrappers_c.inc

57

While the test requires the check, is there something that always prevents us from defining mallinfo2? I don't think it would conflict with anything, and it would be there for people to use it if they want.

[vitalybuka]

define always

compiler-rt/lib/scudo/standalone/tests/wrappers_c_test.cpp

 #include "tests/scudo_unit_test.h"
 
 #include <errno.h>
 #include <limits.h>
 #include <malloc.h>
 #include <stdlib.h>
 #include <unistd.h>
 
+#ifndef __GLIBC_PREREQ
+#define __GLIBC_PREREQ(x, y) 0
+#endif
+
 extern "C" {
 void malloc_enable(void);
 void malloc_disable(void);
 int malloc_iterate(uintptr_t base, size_t size,
                    void (*callback)(uintptr_t base, size_t size, void *arg),
                    void *arg);
 void *valloc(size_t size);
 void *pvalloc(size_t size);
#if !SCUDO_FUCHSIA
   free(P);
 #endif
 
   EXPECT_EQ(valloc(SIZE_MAX), nullptr);
 }
 
 #if !SCUDO_FUCHSIA
 TEST(ScudoWrappersCTest, MallInfo) {
+  // mallinfo is deprecated.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
   const size_t BypassQuarantineSize = 1024U;
-
   struct mallinfo MI = mallinfo();
   size_t Allocated = MI.uordblks;
   void *P = malloc(BypassQuarantineSize);
   EXPECT_NE(P, nullptr);
   MI = mallinfo();
   EXPECT_GE(static_cast<size_t>(MI.uordblks), Allocated + BypassQuarantineSize);
   EXPECT_GT(static_cast<size_t>(MI.hblkhd), 0U);
   size_t Free = MI.fordblks;
   free(P);
   MI = mallinfo();
   EXPECT_GE(static_cast<size_t>(MI.fordblks), Free + BypassQuarantineSize);
+#pragma clang diagnostic pop
+}
+#endif
+
+#if __GLIBC_PREREQ(2, 33)
+TEST(ScudoWrappersCTest, MallInfo2) {
+  const size_t BypassQuarantineSize = 1024U;
+  struct mallinfo2 MI = mallinfo2();
+  size_t Allocated = MI.uordblks;
+  void *P = malloc(BypassQuarantineSize);
+  EXPECT_NE(P, nullptr);
+  MI = mallinfo2();
+  EXPECT_GE(MI.uordblks, Allocated + BypassQuarantineSize);
+  EXPECT_GT(MI.hblkhd, 0U);
+  size_t Free = MI.fordblks;
+  free(P);
+  MI = mallinfo2();
+  EXPECT_GE(MI.fordblks, Free + BypassQuarantineSize);
 }
 #endif
 
 static uintptr_t BoundaryP;
 static size_t Count;
 
 static void callback(uintptr_t Base, size_t Size, void *Arg) {
   if (scudo::archSupportsMemoryTagging()) {

compiler-rt/lib/scudo/standalone/wrappers_c.h

struct __scudo_mallinfo {
   __scudo_mallinfo_data_t hblkhd;
   __scudo_mallinfo_data_t usmblks;
   __scudo_mallinfo_data_t fsmblks;
   __scudo_mallinfo_data_t uordblks;
   __scudo_mallinfo_data_t fordblks;
   __scudo_mallinfo_data_t keepcost;
 };
 
+struct __scudo_mallinfo2 {
+  size_t arena;
+  size_t ordblks;
+  size_t smblks;
+  size_t hblks;
+  size_t hblkhd;
+  size_t usmblks;
+  size_t fsmblks;
+  size_t uordblks;
+  size_t fordblks;
+  size_t keepcost;
+};
+
 // Android sometimes includes malloc.h no matter what, which yields to
 // conflicting return types for mallinfo() if we use our own structure. So if
 // struct mallinfo is declared (#define courtesy of malloc.h), use it directly.
 #if STRUCT_MALLINFO_DECLARED
 #define SCUDO_MALLINFO mallinfo
 #else
 #define SCUDO_MALLINFO __scudo_mallinfo
 #endif
 
 #endif // SCUDO_WRAPPERS_C_H_

compiler-rt/lib/scudo/standalone/wrappers_c.inc

INTERFACE WEAK struct SCUDO_MALLINFO SCUDO_PREFIX(mallinfo)(void) {
   // Total allocated space (bytes)
   Info.uordblks =
       static_cast<__scudo_mallinfo_data_t>(Stats[scudo::StatAllocated]);
   // Total free space (bytes)
   Info.fordblks = Info.fsmblks;
   return Info;
 }
 
+INTERFACE WEAK struct __scudo_mallinfo2 SCUDO_PREFIX(mallinfo2)(void) {
+  struct __scudo_mallinfo2 Info = {};
+  scudo::StatCounters Stats;
+  SCUDO_ALLOCATOR.getStats(Stats);
+  // Space allocated in mmapped regions (bytes)
+  Info.hblkhd = Stats[scudo::StatMapped];
+  // Maximum total allocated space (bytes)
+  Info.usmblks = Info.hblkhd;
+  // Space in freed fastbin blocks (bytes)
+  Info.fsmblks = Stats[scudo::StatFree];
+  // Total allocated space (bytes)
+  Info.uordblks = Stats[scudo::StatAllocated];
+  // Total free space (bytes)
+  Info.fordblks = Info.fsmblks;
+  return Info;
+}
+
 INTERFACE WEAK void *SCUDO_PREFIX(malloc)(size_t size) {
   return scudo::setErrnoOnNull(SCUDO_ALLOCATOR.allocate(
       size, scudo::Chunk::Origin::Malloc, SCUDO_MALLOC_ALIGNMENT));
 }
 
 #if SCUDO_ANDROID
 INTERFACE WEAK size_t SCUDO_PREFIX(malloc_usable_size)(const void *ptr) {
 #else