From 83f3d820f19360a3d733af79e89af352bbf0aa14 Mon Sep 17 00:00:00 2001
From: Leonid Yuriev <leo@yuriev.ru>
Date: Fri, 5 Oct 2018 15:41:27 +0300
Subject: [PATCH] mdbx-windows: refine debug-logging.

---
 src/mdbx.c | 24 ++++++++++++++++++++++++
 src/osal.c | 23 +++++++++++++++++------
 src/osal.h |  4 +++-
 3 files changed, 44 insertions(+), 7 deletions(-)

diff --git a/src/mdbx.c b/src/mdbx.c
index 883b7a31..d621eb57 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -1389,6 +1389,30 @@ void __cold mdbx_debug_log(int type, const char *function, int line,
   if (mdbx_debug_logger)
     mdbx_debug_logger(type, function, line, fmt, args);
   else {
+#if defined(_WIN32) || defined(_WIN64)
+    if (IsDebuggerPresent()) {
+      int prefix_len = 0;
+      char *prefix = nullptr;
+      if (function && line > 0)
+        prefix_len = mdbx_asprintf(&prefix, "%s:%d ", function, line);
+      else if (function)
+        prefix_len = mdbx_asprintf(&prefix, "%s: ", function);
+      else if (line > 0)
+        prefix_len = mdbx_asprintf(&prefix, "%d: ", line);
+      if (prefix_len > 0 && prefix) {
+        OutputDebugStringA(prefix);
+        free(prefix);
+      }
+      char *msg = nullptr;
+      int msg_len = mdbx_vasprintf(&msg, fmt, args);
+      if (msg_len > 0 && msg) {
+        OutputDebugStringA(msg);
+        free(msg);
+      }
+      va_end(args);
+      return;
+    }
+#endif
     if (function && line > 0)
       fprintf(stderr, "%s:%d ", function, line);
     else if (function)
diff --git a/src/osal.c b/src/osal.c
index c2fced0b..2a037447 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -193,11 +193,9 @@ __cold void mdbx_panic(const char *fmt, ...) {
 
 /*----------------------------------------------------------------------------*/
 
-#ifndef mdbx_asprintf
-int mdbx_asprintf(char **strp, const char *fmt, ...) {
-  va_list ap, ones;
-
-  va_start(ap, fmt);
+#ifndef mdbx_vasprintf
+int mdbx_vasprintf(char **strp, const char *fmt, va_list ap) {
+  va_list ones;
   va_copy(ones, ap);
 #ifdef _MSC_VER
   int needed = _vscprintf(fmt, ap);
@@ -207,7 +205,6 @@ int mdbx_asprintf(char **strp, const char *fmt, ...) {
 #else
 #error FIXME
 #endif
-  va_end(ap);
 
   if (unlikely(needed < 0 || needed >= INT_MAX)) {
     *strp = nullptr;
@@ -218,7 +215,11 @@ int mdbx_asprintf(char **strp, const char *fmt, ...) {
   *strp = malloc(needed + 1);
   if (unlikely(*strp == nullptr)) {
     va_end(ones);
+#if defined(_WIN32) || defined(_WIN64)
     SetLastError(MDBX_ENOMEM);
+#else
+    errno = MDBX_ENOMEM;
+#endif
     return -1;
   }
 
@@ -237,6 +238,16 @@ int mdbx_asprintf(char **strp, const char *fmt, ...) {
   }
   return actual;
 }
+#endif /* mdbx_vasprintf */
+
+#ifndef mdbx_asprintf
+int mdbx_asprintf(char **strp, const char *fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  int rc = mdbx_vasprintf(strp, fmt, ap);
+  va_end(ap);
+  return rc;
+}
 #endif /* mdbx_asprintf */
 
 #ifndef mdbx_memalign_alloc
diff --git a/src/osal.h b/src/osal.h
index 5cca43b6..0f3da8a8 100644
--- a/src/osal.h
+++ b/src/osal.h
@@ -386,8 +386,10 @@ void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
 
 #if __GLIBC_PREREQ(2, 1)
 #define mdbx_asprintf asprintf
+#define mdbx_vasprintf vasprintf
 #else
-int mdbx_asprintf(char **strp, const char *fmt, ...);
+__printf_args(2, 3) int mdbx_asprintf(char **strp, const char *fmt, ...);
+int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
 #endif
 
 #ifdef _MSC_VER