finish helper functions

build/file_header.txt

@@ -0,0 +1,15 @@
+// Copyright (C) 2025 @Vloldik
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// This file is generated automatically, do not edit it manually.

build/rust_build.rs

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+/**
+ * This file represents content of https://github.com/google/libphonenumber/tree/master/tools/cpp
+ */
+
+use std::{collections::BTreeMap, fs::File, io::{BufRead, BufReader}, num::ParseIntError, path::Path};
+
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+enum BuildError {
+    #[error("IO error occurred: {0}")]
+    IO(#[from] std::io::Error),
+
+    #[error("Line {line_num} is too long (max is {max_len} bytes)")]
+    LineTooLong { line_num: usize, max_len: usize },
+
+    #[error("Failed to parse prefix '{prefix}': {source}")]
+    PrefixParseError {
+        prefix: String,
+        #[source]
+        source: ParseIntError,
+    },
+}
+
+fn parse_prefixes(path: &str, prefixes: &mut BTreeMap<i32, String>) -> Result<(), BuildError> {
+    prefixes.clear();
+
+    let input = File::open(path)?; 
+    const MAX_LINE_LENGTH: usize = 2 * 1024;
+    
+    let mut reader = BufReader::new(input);
+    let mut line_buffer = String::with_capacity(MAX_LINE_LENGTH);
+    let mut line_number = 0;
+
+    loop {
+        line_number += 1;
+        line_buffer.clear();
+
+        let bytes_read = reader.read_line(&mut line_buffer)?;
+        if bytes_read == 0 {
+            break;
+        }
+
+        if !line_buffer.ends_with('\n') {
+             return Err(BuildError::LineTooLong {
+                line_num: line_number,
+                max_len: MAX_LINE_LENGTH,
+            });
+        }
+        
+        let line = line_buffer.trim();
+        if line.is_empty() || line.starts_with('#') {
+            continue;
+        }
+
+        if let Some((prefix_str, desc)) = line.split_once('|') {
+            if prefix_str.is_empty() {
+                continue;
+            }
+            let prefix_code = prefix_str.parse().map_err(|e| BuildError::PrefixParseError {
+                prefix: prefix_str.to_string(),
+                source: e,
+            })?;
+            prefixes.insert(prefix_code, desc.to_string());
+        }
+    }
+
+    Ok(())
+}
+
+
+
+fn main() -> Result<(), BuildError> {
+    protobuf_codegen::Codegen::new()
+        .includes(["resources"])
+        .input("resources/phonemetadata.proto")
+        .input("resources/phonenumber.proto")
+        .cargo_out_dir("proto_gen")
+        .run_from_script();
+    Ok(())
+}