From bd672a558342bff6d36ada4ea2ba9ec4ffc9a2a9 Mon Sep 17 00:00:00 2001
From: Leonid Yuriev <leo@yuriev.ru>
Date: Mon, 20 Aug 2018 12:30:09 +0300
Subject: [PATCH] mdbx: backport - add mdbx_limits_xyz() (squashed).

Change-Id: I56c79704c59386a0c4d84b001020484c23925e6c
---
 mdbx.h       |  7 ++++++-
 src/mdbx.c   | 45 +++++++++++++++++++++++++++++++++++++--------
 test/main.cc |  6 +++---
 3 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/mdbx.h b/mdbx.h
index 276c8ea6..2d15cc24 100644
--- a/mdbx.h
+++ b/mdbx.h
@@ -900,7 +900,7 @@ LIBMDBX_API int mdbx_env_set_maxdbs(MDBX_env *env, MDBX_dbi dbs);
  *
  * Returns The maximum size of a key we can write. */
 LIBMDBX_API int mdbx_env_get_maxkeysize(MDBX_env *env);
-LIBMDBX_API int mdbx_get_maxkeysize(size_t pagesize);
+LIBMDBX_API int mdbx_get_maxkeysize(intptr_t pagesize);
 
 /* Set application information associated with the MDBX_env.
  *
@@ -1673,6 +1673,11 @@ LIBMDBX_API int mdbx_is_dirty(const MDBX_txn *txn, const void *ptr);
 LIBMDBX_API int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
                                   uint64_t increment);
 
+LIBMDBX_API int mdbx_limits_pgsize_min(void);
+LIBMDBX_API int mdbx_limits_pgsize_max(void);
+LIBMDBX_API intptr_t mdbx_limits_dbsize_min(intptr_t pagesize);
+LIBMDBX_API intptr_t mdbx_limits_dbsize_max(intptr_t pagesize);
+
 /*----------------------------------------------------------------------------*/
 /* attribute support functions for Nexenta */
 typedef uint_fast64_t mdbx_attr_t;
diff --git a/src/mdbx.c b/src/mdbx.c
index 95e74ca4..d5a369c9 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -4897,16 +4897,15 @@ int __cold mdbx_env_get_maxkeysize(MDBX_env *env) {
 #define mdbx_maxgc_ov1page(pagesize)                                           \
   (((pagesize)-PAGEHDRSZ) / sizeof(pgno_t) - 1)
 
-int mdbx_get_maxkeysize(size_t pagesize) {
-  if (pagesize == 0)
-    pagesize = mdbx_syspagesize();
-
-  intptr_t nodemax = mdbx_nodemax(pagesize);
-  if (nodemax < 0)
+int mdbx_get_maxkeysize(intptr_t pagesize) {
+  if (pagesize < 1)
+    pagesize = (intptr_t)mdbx_syspagesize();
+  else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
+                    pagesize > (intptr_t)MAX_PAGESIZE ||
+                    !mdbx_is_power2((size_t)pagesize)))
     return -MDBX_EINVAL;
 
-  intptr_t maxkey = mdbx_maxkey(nodemax);
-  return (maxkey > 0 && maxkey < INT_MAX) ? (int)maxkey : -MDBX_EINVAL;
+  return mdbx_maxkey(mdbx_nodemax(pagesize));
 }
 
 static void __cold mdbx_setup_pagesize(MDBX_env *env, const size_t pagesize) {
@@ -12233,6 +12232,36 @@ int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
   return MDBX_SUCCESS;
 }
 
+/*----------------------------------------------------------------------------*/
+
+__cold int mdbx_limits_pgsize_min(void) { return MIN_PAGESIZE; }
+
+__cold int mdbx_limits_pgsize_max(void) { return MAX_PAGESIZE; }
+
+__cold intptr_t mdbx_limits_dbsize_min(intptr_t pagesize) {
+  if (pagesize < 1)
+    pagesize = (intptr_t)mdbx_syspagesize();
+  else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
+                    pagesize > (intptr_t)MAX_PAGESIZE ||
+                    !mdbx_is_power2((size_t)pagesize)))
+    return -MDBX_EINVAL;
+
+  return MIN_PAGENO * pagesize;
+}
+
+__cold intptr_t mdbx_limits_dbsize_max(intptr_t pagesize) {
+  if (pagesize < 1)
+    pagesize = (intptr_t)mdbx_syspagesize();
+  else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
+                    pagesize > (intptr_t)MAX_PAGESIZE ||
+                    !mdbx_is_power2((size_t)pagesize)))
+    return -MDBX_EINVAL;
+
+  const uint64_t limit = MAX_PAGENO * (uint64_t)pagesize;
+  return (limit < (intptr_t)MAX_MAPSIZE) ? (intptr_t)limit
+                                         : (intptr_t)MAX_PAGESIZE;
+}
+
 /*----------------------------------------------------------------------------*/
 /* attribute support functions for Nexenta */
 
diff --git a/test/main.cc b/test/main.cc
index e6e0e177..d417480d 100644
--- a/test/main.cc
+++ b/test/main.cc
@@ -1,4 +1,4 @@
-/*
+/*
  * Copyright 2017-2018 Leonid Yuriev <leo@yuriev.ru>
  * and other libmdbx authors: please see AUTHORS file.
  * All rights reserved.
@@ -195,8 +195,8 @@ int main(int argc, char *const argv[]) {
     }
     if (config::parse_option(
             argc, argv, narg, "keylen.max", params.keylen_max, config::no_scale,
-            0, std::min(mdbx_get_maxkeysize(0), (int)UINT16_MAX))) {
-
+            0,
+            std::min((unsigned)mdbx_get_maxkeysize(0), (unsigned)UINT16_MAX))) {
       if (params.keylen_min > params.keylen_max)
         params.keylen_min = params.keylen_max;
       continue;