From 04f1fcfbe1ae36a4295d3ec4d5979035d30a2d56 Mon Sep 17 00:00:00 2001
From: folex <0xdxdy@gmail.com>
Date: Wed, 14 Aug 2019 20:19:39 +0300
Subject: [PATCH] Use sqlite-specific ffi

---
 backend-rust/src/lib.rs | 27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/backend-rust/src/lib.rs b/backend-rust/src/lib.rs
index 7b3c2cd..1e0eb90 100644
--- a/backend-rust/src/lib.rs
+++ b/backend-rust/src/lib.rs
@@ -6,25 +6,23 @@ fn init() {
 }
 
 #[invocation_handler(init_fn = init)]
-fn azaza(_arg: String) -> String {
-    println!("Hello, world!");
-    info!("hello");
+fn run(arg: String) -> String {
+    query(arg)
+}
+
+fn query(query: String) -> String {
+    info!("executing query: '{}'", query);
 
-    let query = "CREATE VIRTUAL TABLE users USING FTS5(body)";
     unsafe {
         let bytes = query.as_bytes();
         let query_ptr = ffi::allocate(bytes.len());
-        info!("allocated");
 
         for (i, byte) in bytes.iter().enumerate() {
-            info!("will store {} {}", i, *byte);
             let ptr = query_ptr + i as i32;
             ffi::store(ptr, *byte);
         }
-        info!("stored");
 
         let result_ptr = ffi::invoke(query_ptr, bytes.len());
-        info!("invoked");
 
         let mut result_size = 0;
         for i in 0u8..4u8 {
@@ -32,23 +30,19 @@ fn azaza(_arg: String) -> String {
             let b = ffi::load(ptr);
             result_size = result_size | (b >> 8*i)
         }
-        info!("loaded");
 
         let mut result_bytes = vec![0; result_size as usize];
-        for i in 0u8..result_size {
+        for i in 4u8..result_size {
             let ptr = result_ptr + i as i32;
             let b = ffi::load(ptr);
-            result_bytes[i as usize] = b;
+            result_bytes[i as usize - 4] = b;
         }
-        info!("parsed to bytes");
 
         let result_str = std::str::from_utf8(result_bytes.as_slice());
         if result_str.is_err() {
             info!("unable to decode result from result_bytes: {:?}", result_bytes);
         }
 
-        info!("result is {:?}", result_str);
-
         result_str.expect("unable to decode result").to_string()
     }
 }
@@ -56,10 +50,15 @@ fn azaza(_arg: String) -> String {
 pub mod ffi {
     #[link(wasm_import_module = "sqlite")]
     extern "C" {
+        #[link_name="sqlite_allocate"]
         pub fn allocate(size: usize) -> i32;
+        #[link_name="sqlite_deallocate"]
         pub fn deallocate(ptr: i32, size: usize);
+        #[link_name="sqlite_invoke"]
         pub fn invoke(ptr: i32, size: usize) -> i32;
+        #[link_name="sqlite_store"]
         pub fn store(ptr: i32, byte: u8);
+        #[link_name="sqlite_load"]
         pub fn load(ptr: i32) -> u8;
     }
 }
\ No newline at end of file