From ded5269937ca4bad2a990b62461ff3ed2bacabc6 Mon Sep 17 00:00:00 2001
From: Leonid Yuriev <leo@yuriev.ru>
Date: Sun, 14 Oct 2018 01:11:14 +0300
Subject: [PATCH] mdbx-windows: rework mdbx_assert_fail() and mdbx_panic() to
 avoid dependency from CRT.

7 of 17 for https://github.com/leo-yuriev/libmdbx/issues/43

Change-Id: I40dc8d6a7d1d955c13c7d328ee904f0e6f30b248
---
 src/bits.h |  6 ++++++
 src/mdbx.c |  8 ++------
 src/osal.c | 55 +++++++++++++++++++++++++++++++++---------------------
 src/osal.h |  5 -----
 4 files changed, 42 insertions(+), 32 deletions(-)

diff --git a/src/bits.h b/src/bits.h
index 30ae690f..fc7b939e 100644
--- a/src/bits.h
+++ b/src/bits.h
@@ -868,6 +868,9 @@ void mdbx_panic(const char *fmt, ...)
 #endif /* NDEBUG */
 #endif /* MDBX_DEBUG */
 
+LIBMDBX_API void mdbx_assert_fail(const MDBX_env *env, const char *msg,
+                                  const char *func, int line);
+
 #define mdbx_print(fmt, ...)                                                   \
   mdbx_debug_log(MDBX_DBG_PRINT, NULL, 0, fmt, ##__VA_ARGS__)
 
@@ -967,6 +970,9 @@ void mdbx_panic(const char *fmt, ...)
 /* assert(3) variant in transaction context */
 #define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
 
+#undef assert
+#define assert(expr) mdbx_assert(NULL, expr)
+
 /*----------------------------------------------------------------------------*/
 /* Internal prototypes */
 
diff --git a/src/mdbx.c b/src/mdbx.c
index d1ad912c..e18b6a5b 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -40,9 +40,6 @@
 /*----------------------------------------------------------------------------*/
 /* Internal inlines */
 
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-
 static __inline bool mdbx_is_power2(size_t x) { return (x & (x - 1)) == 0; }
 
 static __inline size_t mdbx_roundup2(size_t value, size_t granularity) {
@@ -1409,10 +1406,8 @@ void __cold mdbx_debug_log(int type, const char *function, int line,
         OutputDebugStringA(msg);
         mdbx_free(msg);
       }
-      va_end(args);
-      return;
     }
-#endif
+#else
     if (function && line > 0)
       fprintf(stderr, "%s:%d ", function, line);
     else if (function)
@@ -1421,6 +1416,7 @@ void __cold mdbx_debug_log(int type, const char *function, int line,
       fprintf(stderr, "%d: ", line);
     vfprintf(stderr, fmt, args);
     fflush(stderr);
+#endif
   }
   va_end(args);
 }
diff --git a/src/osal.c b/src/osal.c
index 7306c1d0..99a2c9a9 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -154,13 +154,8 @@ typedef struct _FILE_PROVIDER_EXTERNAL_INFO_V1 {
 /* Prototype should match libc runtime. ISO POSIX (2003) & LSB 3.1 */
 __nothrow __noreturn void __assert_fail(const char *assertion, const char *file,
                                         unsigned line, const char *function);
-#else
-__extern_C __declspec(dllimport) void __cdecl _assert(char const *message,
-                                                      char const *filename,
-                                                      unsigned line);
 #endif /* _MSC_VER */
 
-#ifndef mdbx_assert_fail
 void __cold mdbx_assert_fail(const MDBX_env *env, const char *msg,
                              const char *func, int line) {
 #if MDBX_DEBUG
@@ -174,30 +169,48 @@ void __cold mdbx_assert_fail(const MDBX_env *env, const char *msg,
 
   if (mdbx_debug_logger)
     mdbx_debug_log(MDBX_DBG_ASSERT, func, line, "assert: %s\n", msg);
-#ifndef _MSC_VER
-  __assert_fail(msg, "mdbx", line, func);
+  else {
+#if defined(_WIN32) || defined(_WIN64)
+    char *message = nullptr;
+    const int num = mdbx_asprintf(&message, "\r\nMDBX-ASSERTION: %s, %s:%u",
+                                  func ? func : "unknown", line);
+    if (num < 1 || !message)
+      message = "<troubles with assertion-message preparation>";
+    OutputDebugStringA(message);
+    if (IsDebuggerPresent())
+      DebugBreak();
 #else
-  _assert(msg, func, line);
-#endif /* _MSC_VER */
+    __assert_fail(msg, "mdbx", line, func);
+#endif
+  }
+
+#if defined(_WIN32) || defined(_WIN64)
+  FatalExit(ERROR_UNHANDLED_ERROR);
+#else
+  abort();
+#endif
 }
-#endif /* mdbx_assert_fail */
 
 __cold void mdbx_panic(const char *fmt, ...) {
   va_list ap;
   va_start(ap, fmt);
-#ifdef _MSC_VER
-  if (IsDebuggerPresent()) {
-    OutputDebugStringA("\r\n" FIXME "\r\n");
-    FatalExit(ERROR_UNHANDLED_ERROR);
-  }
-#elif _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L ||                    \
-    (__GLIBC_PREREQ(1, 0) && !__GLIBC_PREREQ(2, 10) && defined(_GNU_SOURCE))
-  vdprintf(STDERR_FILENO, fmt, ap);
-#else
-#error FIXME
-#endif
+
+  char *message = nullptr;
+  const int num = mdbx_vasprintf(&message, fmt, ap);
   va_end(ap);
+  if (num < 1 || !message)
+    message = "<troubles with panic-message preparation>";
+
+#if defined(_WIN32) || defined(_WIN64)
+  OutputDebugStringA("\r\nMDBX-PANIC: ");
+  OutputDebugStringA(message);
+  if (IsDebuggerPresent())
+    DebugBreak();
+  FatalExit(ERROR_UNHANDLED_ERROR);
+#else
+  __assert_fail(message, "mdbx", 0, "panic");
   abort();
+#endif
 }
 
 /*----------------------------------------------------------------------------*/
diff --git a/src/osal.h b/src/osal.h
index 3e2f6a68..e2da2611 100644
--- a/src/osal.h
+++ b/src/osal.h
@@ -393,11 +393,6 @@ static __inline void mdbx_invalidate_cache(void *addr, size_t nbytes) {
 /*----------------------------------------------------------------------------*/
 /* libc compatibility stuff */
 
-#ifndef mdbx_assert_fail
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif /* mdbx_assert_fail */
-
 #if __GLIBC_PREREQ(2, 1)
 #define mdbx_asprintf asprintf
 #define mdbx_vasprintf vasprintf