support for iodbc

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "odbc-sys"
-version = "0.17.1"
+version = "0.17.2"
 authors = ["Markus Klein <markus-klein@live.de>"]
 license = "MIT"
 description = "ODBC ffi bindings"
@@ -16,6 +16,7 @@ categories = ["external-ffi-bindings", "database"]
 [features]
 default = ["odbc_version_3_80"]
 static = []
+iodbc = []
 
 odbc_version_3_50 = []
 odbc_version_3_80 = ["odbc_version_3_50"]

README.md

@@ -20,6 +20,11 @@ Design Goals
 * As it is as of now unlikely to happen that anyone is writing ODBC 2.0 applications in Rust
   therefore deprecated symbols like 'SQLAllocEnv' have been left out intentionally.
 
+Linking
+-------
+
+This library will link against `odbc32.dll` (preinstalled) on Windows systems. On Linux and OS-X it links against `libodbc.so` by default. This is typically provided by [unix-odbc](http://www.unixodbc.org/). Using the `--feature iodbc` you can also link against `libiodbc.so`. This may be interessting if you are trying to connect to some older data sources on OS-X.
+
 Current State
 -------------
 

src/functions.rs

@@ -7,8 +7,10 @@ use crate::{
 
 // static linking is not currently supported here for windows
 #[cfg_attr(windows, link(name = "odbc32"))]
-#[cfg_attr(all(not(windows), not(r#static)), link(name = "odbc"))]
-#[cfg_attr(all(not(windows), r#static), link(name = "odbc", kind = "static"))]
+#[cfg_attr(all(not(windows), not(feature = "static"), not(feature = "iodbc")), link(name = "odbc"))]
+#[cfg_attr(all(not(windows), feature = "static", not(feature = "iodbc")), link(name = "odbc", kind = "static"))]
+#[cfg_attr(all(not(windows), not(feature = "static"), feature = "iodbc"), link(name = "iodbc"))]
+#[cfg_attr(all(not(windows), feature = "static", feature = "iodbc"), link(name = "iodbc", kind = "static"))]
 extern "system" {
     /// Allocates an environment, connection, statement, or descriptor handle.
     ///