From d0e500c8769dbc08725f1bfedd562a0c1d5a0cae Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Sun, 13 Feb 2022 00:24:34 -0500
Subject: [PATCH] win: use GetTickCount64 for uptime again (#3470)

Reverts 442aa1f4696d24a605790b8ad4317696758ee8de, since this is an
improved API in Windows Vista that is now usable as a replacement. It
simplifies the code substantially, while returning nearly the same
result (on my system, the performance counters were 6 seconds behind).

The old code also did not work on Wine-5.0 (where I observed that
`data_size == data_block->HeaderLength`, and so no data was present).
---
 src/win/util.c | 99 +-------------------------------------------------
 1 file changed, 2 insertions(+), 97 deletions(-)

diff --git a/src/win/util.c b/src/win/util.c
index 5283602f..ee70ebc2 100644
--- a/src/win/util.c
+++ b/src/win/util.c
@@ -531,103 +531,8 @@ int uv_resident_set_memory(size_t* rss) {
 
 
 int uv_uptime(double* uptime) {
-  BYTE stack_buffer[4096];
-  BYTE* malloced_buffer = NULL;
-  BYTE* buffer = (BYTE*) stack_buffer;
-  size_t buffer_size = sizeof(stack_buffer);
-  DWORD data_size;
-
-  PERF_DATA_BLOCK* data_block;
-  PERF_OBJECT_TYPE* object_type;
-  PERF_COUNTER_DEFINITION* counter_definition;
-
-  DWORD i;
-
-  for (;;) {
-    LONG result;
-
-    data_size = (DWORD) buffer_size;
-    result = RegQueryValueExW(HKEY_PERFORMANCE_DATA,
-                              L"2",
-                              NULL,
-                              NULL,
-                              buffer,
-                              &data_size);
-    if (result == ERROR_SUCCESS) {
-      break;
-    } else if (result != ERROR_MORE_DATA) {
-      *uptime = 0;
-      return uv_translate_sys_error(result);
-    }
-
-    buffer_size *= 2;
-    /* Don't let the buffer grow infinitely. */
-    if (buffer_size > 1 << 20) {
-      goto internalError;
-    }
-
-    uv__free(malloced_buffer);
-
-    buffer = malloced_buffer = (BYTE*) uv__malloc(buffer_size);
-    if (malloced_buffer == NULL) {
-      *uptime = 0;
-      return UV_ENOMEM;
-    }
-  }
-
-  if (data_size < sizeof(*data_block))
-    goto internalError;
-
-  data_block = (PERF_DATA_BLOCK*) buffer;
-
-  if (wmemcmp(data_block->Signature, L"PERF", 4) != 0)
-    goto internalError;
-
-  if (data_size < data_block->HeaderLength + sizeof(*object_type))
-    goto internalError;
-
-  object_type = (PERF_OBJECT_TYPE*) (buffer + data_block->HeaderLength);
-
-  if (object_type->NumInstances != PERF_NO_INSTANCES)
-    goto internalError;
-
-  counter_definition = (PERF_COUNTER_DEFINITION*) (buffer +
-      data_block->HeaderLength + object_type->HeaderLength);
-  for (i = 0; i < object_type->NumCounters; i++) {
-    if ((BYTE*) counter_definition + sizeof(*counter_definition) >
-        buffer + data_size) {
-      break;
-    }
-
-    if (counter_definition->CounterNameTitleIndex == 674 &&
-        counter_definition->CounterSize == sizeof(uint64_t)) {
-      if (counter_definition->CounterOffset + sizeof(uint64_t) > data_size ||
-          !(counter_definition->CounterType & PERF_OBJECT_TIMER)) {
-        goto internalError;
-      } else {
-        BYTE* address = (BYTE*) object_type + object_type->DefinitionLength +
-                        counter_definition->CounterOffset;
-        uint64_t value = *((uint64_t*) address);
-        *uptime = (double) (object_type->PerfTime.QuadPart - value) /
-                  (double) object_type->PerfFreq.QuadPart;
-        uv__free(malloced_buffer);
-        return 0;
-      }
-    }
-
-    counter_definition = (PERF_COUNTER_DEFINITION*)
-        ((BYTE*) counter_definition + counter_definition->ByteLength);
-  }
-
-  /* If we get here, the uptime value was not found. */
-  uv__free(malloced_buffer);
-  *uptime = 0;
-  return UV_ENOSYS;
-
- internalError:
-  uv__free(malloced_buffer);
-  *uptime = 0;
-  return UV_EIO;
+  *uptime = GetTickCount64() / 1000.0;
+  return 0;
 }