Replace cqdb C binding with Rust implementation (#19)

Author: messense

crfsuite-sys/Cargo.toml

@@ -14,7 +14,7 @@ edition = "2018"
 [dependencies]
 libc = "0.2"
 liblbfgs-sys = "0.1.0"
-cqdb-sys = "0.1.0"
+libcqdb = "0.1.0"
 
 [build-dependencies]
 cc = "1.0"

crfsuite-sys/build.rs

@@ -13,7 +13,7 @@ fn fail_on_empty_directory(name: &str) {
 
 fn build_crfsuite() {
     let mut cfg = cmake::Config::new("");
-    cfg.register_dep("cqdb").register_dep("lbfgs");
+    cfg.register_dep("libcqdb").register_dep("lbfgs");
     if cfg!(target_os = "macos") {
         let target_arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap();
         if target_arch == "x86_64" {
@@ -22,7 +22,7 @@ fn build_crfsuite() {
     }
     let dst = cfg.build();
     println!("cargo:rustc-link-search=native={}/lib", dst.display());
-    println!("cargo:rustc-link-lib=static=cqdb");
+    // println!("cargo:rustc-link-lib=static=libcqdb");
     println!("cargo:rustc-link-lib=static=lbfgs");
     println!("cargo:rustc-link-lib=static=crfsuite");
     println!("cargo:root={}", dst.to_str().unwrap());

crfsuite-sys/src/lib.rs

@@ -2,6 +2,10 @@
 #![allow(non_snake_case)]
 #![allow(non_upper_case_globals)]
 
+/// Force linking with libcqdb
+#[doc(hidden)]
+pub use libcqdb::*;
+
 mod bindings;
 
 pub use self::bindings::*;