Reintroduce the MDB_IDL_LOGN feature flags

heed/Cargo.toml

@@ -72,6 +72,26 @@ unbounded_depth = ["heed-types/unbounded_depth"]
 # <https://github.com/LMDB/lmdb/blob/3947014aed7ffe39a79991fa7fb5b234da47ad1a/libraries/liblmdb/lmdb.h#L46-L69>
 posix-sem = ["lmdb-master-sys/posix-sem"]
 
+# These features configure the MDB_IDL_LOGN macro, which determines
+# the size of the free and dirty page lists (and thus the amount of memory
+# allocated when opening an LMDB environment in read-write mode).
+#
+# Each feature defines MDB_IDL_LOGN as the value in the name of the feature.
+# That means these features are mutually exclusive, and you must not specify
+# more than one at the same time (or the crate will fail to compile).
+#
+# For more information on the motivation for these features (and their effect),
+# see https://github.com/mozilla/lmdb/pull/2.
+mdb_idl_logn_8 = ["lmdb-master-sys/mdb_idl_logn_8"]
+mdb_idl_logn_9 = ["lmdb-master-sys/mdb_idl_logn_9"]
+mdb_idl_logn_10 = ["lmdb-master-sys/mdb_idl_logn_10"]
+mdb_idl_logn_11 = ["lmdb-master-sys/mdb_idl_logn_11"]
+mdb_idl_logn_12 = ["lmdb-master-sys/mdb_idl_logn_12"]
+mdb_idl_logn_13 = ["lmdb-master-sys/mdb_idl_logn_13"]
+mdb_idl_logn_14 = ["lmdb-master-sys/mdb_idl_logn_14"]
+mdb_idl_logn_15 = ["lmdb-master-sys/mdb_idl_logn_15"]
+mdb_idl_logn_16 = ["lmdb-master-sys/mdb_idl_logn_16"]
+
 [[example]]
 name = "rmp-serde"
 required-features = ["serde-rmp"]

lmdb-master-sys/Cargo.toml

@@ -40,3 +40,23 @@ asan = []
 fuzzer = []
 fuzzer-no-link = []
 posix-sem = []
+
+# These features configure the MDB_IDL_LOGN macro, which determines
+# the size of the free and dirty page lists (and thus the amount of memory
+# allocated when opening an LMDB environment in read-write mode).
+#
+# Each feature defines MDB_IDL_LOGN as the value in the name of the feature.
+# That means these features are mutually exclusive, and you must not specify
+# more than one at the same time (or the crate will fail to compile).
+#
+# For more information on the motivation for these features (and their effect),
+# see https://github.com/mozilla/lmdb/pull/2.
+mdb_idl_logn_8 = []
+mdb_idl_logn_9 = []
+mdb_idl_logn_10 = []
+mdb_idl_logn_11 = []
+mdb_idl_logn_12 = []
+mdb_idl_logn_13 = []
+mdb_idl_logn_14 = []
+mdb_idl_logn_15 = []
+mdb_idl_logn_16 = []

lmdb-master-sys/build.rs

@@ -10,6 +10,98 @@ mod generate;
 use std::env;
 use std::path::PathBuf;
 
+#[cfg(all(
+    feature = "mdb_idl_logn_8",
+    not(any(
+        feature = "mdb_idl_logn_9",
+        feature = "mdb_idl_logn_10",
+        feature = "mdb_idl_logn_11",
+        feature = "mdb_idl_logn_12",
+        feature = "mdb_idl_logn_13",
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16"
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 8;
+#[cfg(all(
+    feature = "mdb_idl_logn_9",
+    not(any(
+        feature = "mdb_idl_logn_10",
+        feature = "mdb_idl_logn_11",
+        feature = "mdb_idl_logn_12",
+        feature = "mdb_idl_logn_13",
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16"
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 9;
+#[cfg(all(
+    feature = "mdb_idl_logn_10",
+    not(any(
+        feature = "mdb_idl_logn_11",
+        feature = "mdb_idl_logn_12",
+        feature = "mdb_idl_logn_13",
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16"
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 10;
+#[cfg(all(
+    feature = "mdb_idl_logn_11",
+    not(any(
+        feature = "mdb_idl_logn_12",
+        feature = "mdb_idl_logn_13",
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16"
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 11;
+#[cfg(all(
+    feature = "mdb_idl_logn_12",
+    not(any(
+        feature = "mdb_idl_logn_13",
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16"
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 12;
+#[cfg(all(
+    feature = "mdb_idl_logn_13",
+    not(any(
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16"
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 13;
+#[cfg(all(
+    feature = "mdb_idl_logn_14",
+    not(any(feature = "mdb_idl_logn_15", feature = "mdb_idl_logn_16"))
+))]
+const MDB_IDL_LOGN: u8 = 14;
+#[cfg(all(feature = "mdb_idl_logn_15", not(any(feature = "mdb_idl_logn_16"))))]
+const MDB_IDL_LOGN: u8 = 15;
+#[cfg(any(
+    feature = "mdb_idl_logn_16",
+    not(any(
+        feature = "mdb_idl_logn_8",
+        feature = "mdb_idl_logn_9",
+        feature = "mdb_idl_logn_10",
+        feature = "mdb_idl_logn_11",
+        feature = "mdb_idl_logn_12",
+        feature = "mdb_idl_logn_13",
+        feature = "mdb_idl_logn_14",
+        feature = "mdb_idl_logn_15",
+        feature = "mdb_idl_logn_16",
+    ))
+))]
+const MDB_IDL_LOGN: u8 = 16;
+
 macro_rules! warn {
     ($message:expr) => {
         println!("cargo:warning={}", $message);
@@ -33,6 +125,7 @@ fn main() {
     let mut builder = cc::Build::new();
 
     builder
+        .define("MDB_IDL_LOGN", Some(MDB_IDL_LOGN.to_string().as_str()))
         .file(lmdb.join("mdb.c"))
         .file(lmdb.join("midl.c"))
         // https://github.com/mozilla/lmdb/blob/b7df2cac50fb41e8bd16aab4cc5fd167be9e032a/libraries/liblmdb/Makefile#L23