chore: move __c_cpp/* to __ffi

__ffi/c_export/Cargo.lock

@@ -0,0 +1,16 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "c_export"
+version = "0.1.0"
+dependencies = [
+ "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.60"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[metadata]
+"checksum libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)" = "d44e80633f007889c7eff624b709ab43c92d708caad982295768a7b13ca3b5eb"

__ffi/c_export/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "c_export"
+version = "0.1.0"
+authors = ["Hatter Jiang <jht5945@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[lib]
+name = "stringtools"
+crate-type = ["dylib"]
+
+[dependencies]
+libc = "0.2.60"

__ffi/c_export/README.md

@@ -0,0 +1,29 @@
+
+Rust libray build:
+```
+cargo build
+```
+
+
+Python test:
+```
+python call_in_python.py
+```
+
+
+C test:
+```
+gcc call_in_c.c -L target/debug/ -lstringtools
+```
+
+
+NodeJS test:
+```
+npm install ffi
+node call_in_node.js
+```
+
+
+Reference:
+http://siciarz.net/24-days-of-rust-calling-rust-from-other-languages/
+

__ffi/c_export/call_in_c.c

@@ -0,0 +1,9 @@
+#include <stdint.h>
+#include <stdio.h>
+
+int32_t count_substrings(const char* value, const char* substr);
+
+int main() {
+    printf("%d\n", count_substrings("banana", "na"));
+    return 0;
+}

__ffi/c_export/call_in_node.js

@@ -0,0 +1,8 @@
+var ffi = require('ffi');
+
+var stringtools = ffi.Library('target/debug/libstringtools.dylib', {
+    'count_substrings': ['int', ['string', 'string']]
+});
+
+console.log(stringtools.count_substrings("banana", "na"));
+

__ffi/c_export/call_in_python.py

@@ -0,0 +1,5 @@
+import ctypes
+
+stringtools = ctypes.CDLL("target/debug/libstringtools.dylib")
+print(stringtools.count_substrings(b"banana", b"na"))
+

__ffi/c_export/src/lib.rs

@@ -0,0 +1,17 @@
+extern crate libc;
+
+use std::ffi::CStr;
+use libc::c_char;
+
+#[no_mangle]
+pub extern "C" fn count_substrings(value: *const c_char, substr: *const c_char) -> i32 {
+    let c_value = unsafe { CStr::from_ptr(value) };
+    let c_substr = unsafe { CStr::from_ptr(substr) };
+    match c_value.to_str() {
+        Ok(value) => match c_substr.to_str() {
+            Ok(substr) => value.match_indices(substr).count() as i32,
+            Err(_) => -1,
+        },
+        Err(_) => -1,
+    }
+}

__ffi/cpp/Cargo.lock

@@ -0,0 +1,161 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "aho-corasick"
+version = "0.7.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "743ad5a418686aad3b87fd14c43badd828cf26e214a00f92a384291cf22e1811"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "byteorder"
+version = "1.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
+
+[[package]]
+name = "cc"
+version = "1.0.50"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "95e28fa049fda1c330bcf9d723be7663a899c4679724b34c81e9f5a326aab8cd"
+
+[[package]]
+name = "cpp"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0d94d130fd605c2df503d59a2784d8ecf8326d2311b50c848dff7bc7b1a61bd"
+dependencies = [
+ "cpp_macros",
+]
+
+[[package]]
+name = "cpp_build"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7a67671b8ace8c2eeab3f6e00edd0bfab24026208fa5d039808d6b6efe4beb6"
+dependencies = [
+ "cc",
+ "cpp_common",
+ "lazy_static",
+ "proc-macro2",
+ "regex",
+ "syn",
+ "unicode-xid",
+]
+
+[[package]]
+name = "cpp_common"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b827ced56ffc05f4c918858040091d26f4b4176c670270be85538fe58d89923"
+dependencies = [
+ "lazy_static",
+ "proc-macro2",
+ "syn",
+]
+
+[[package]]
+name = "cpp_macros"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a5c116686c51a8e0b0e0ad5e85121be6a26f175d3193e3507e0b2d8bed65190d"
+dependencies = [
+ "aho-corasick",
+ "byteorder",
+ "cpp_common",
+ "if_rust_version",
+ "lazy_static",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "if_rust_version"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46dbcb333e86939721589d25a3557e180b52778cb33c7fdfe9e0158ff790d5ec"
+
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+
+[[package]]
+name = "memchr"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3197e20c7edb283f87c071ddfc7a2cca8f8e0b888c242959846a6fce03c72223"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3acb317c6ff86a4e579dfa00fc5e6cca91ecbb4e7eb2df0468805b674eb88548"
+dependencies = [
+ "unicode-xid",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "053a8c8bcc71fcce321828dc897a98ab9760bef03a4fc36693c231e5b3216cfe"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "regex"
+version = "1.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "322cf97724bea3ee221b78fe25ac9c46114ebb51747ad5babd51a2fc6a8235a8"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+ "thread_local",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b28dfe3fe9badec5dbf0a79a9cccad2cfc2ab5484bdb3e44cbd1ae8b3ba2be06"
+
+[[package]]
+name = "rust_sample_cpp"
+version = "0.1.0"
+dependencies = [
+ "cpp",
+ "cpp_build",
+]
+
+[[package]]
+name = "syn"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "af6f3550d8dff9ef7dc34d384ac6f107e5d31c8f57d9f28e0081503f547ac8f5"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-xid",
+]
+
+[[package]]
+name = "thread_local"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
+dependencies = [
+ "lazy_static",
+]
+
+[[package]]
+name = "unicode-xid"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"

__ffi/cpp/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "rust_sample_cpp"
+version = "0.1.0"
+authors = ["Hatter Jiang <jht5945@gmail.com>"]
+edition = "2018"
+build = "build.rs"
+
+[dependencies]
+cpp = "0.5.4"
+
+[build-dependencies]
+cpp_build = "0.5.4"
+

__ffi/cpp/build.rs

@@ -0,0 +1,5 @@
+extern crate cpp_build;
+
+fn main() {
+    cpp_build::build("src/main.rs");
+}

__ffi/cpp/src/main.rs

@@ -0,0 +1,16 @@
+#[macro_use]
+extern crate cpp;
+
+cpp!{{
+    #include <stdio.h>
+    #include <iostream>
+}}
+
+fn main() {
+    unsafe {
+        cpp!([] {
+            printf("Hello, World!\n");
+            std::cout << "Hello, World2!" << std::endl;
+        });
+    }
+}