use once_cell::sync::OnceCell;
use rustc_middle::ty::TyCtxt;
use rustc_span::Span;
use crate::{
analysis::{
core::dataflow::{graph::*, *},
utils::def_path::DefPath,
},
utils::log::{relative_pos_range, span_to_filename, span_to_line_number, span_to_source_code},
};
use annotate_snippets::{Level, Renderer, Snippet};
use super::super::super::LEVEL;
use super::super::super::NO_STD;
use crate::analysis::opt::OptCheck;
static DEFPATHS: OnceCell<DefPaths> = OnceCell::new();
struct DefPaths {
vec_extend_from_slice: DefPath,
}
impl DefPaths {
pub fn new(tcx: &TyCtxt<'_>) -> Self {
let no_std = NO_STD.lock().unwrap();
if *no_std {
Self {
vec_extend_from_slice: DefPath::new("alloc::vec::Vec::extend_from_slice", &tcx),
}
} else {
Self {
vec_extend_from_slice: DefPath::new("std::vec::Vec::extend_from_slice", &tcx),
}
}
}
}
pub struct BoundsExtendCheck {
pub record: Vec<Span>,
}
fn is_extend_from_slice(node: &GraphNode) -> bool {
let def_paths = DEFPATHS.get().unwrap();
for op in node.ops.iter() {
if let NodeOp::Call(def_id) = op {
if *def_id == def_paths.vec_extend_from_slice.last_def_id() {
return true;
}
}
}
false
}
impl OptCheck for BoundsExtendCheck {
fn new() -> Self {
Self { record: Vec::new() }
}
fn check(&mut self, graph: &Graph, tcx: &TyCtxt) {
let level = LEVEL.lock().unwrap();
if *level <= 1 {
return;
}
let _ = &DEFPATHS.get_or_init(|| DefPaths::new(tcx));
for node in graph.nodes.iter() {
if is_extend_from_slice(node) {
self.record.push(node.span);
}
}
}
fn report(&self, graph: &Graph) {
for span in self.record.iter() {
report_extend_bug(graph, *span);
}
}
fn cnt(&self) -> usize {
self.record.len()
}
}
fn report_extend_bug(graph: &Graph, span: Span) {
let code_source = span_to_source_code(graph.span);
let filename = span_to_filename(graph.span);
let snippet = Snippet::source(&code_source)
.line_start(span_to_line_number(graph.span))
.origin(&filename)
.fold(true)
.annotation(
Level::Error
.span(relative_pos_range(graph.span, span))
.label("Checked here."),
);
let message = Level::Warning
.title("Unnecessary bound checkings detected")
.snippet(snippet)
.footer(Level::Help.title("Manipulate memory directly."));
let renderer = Renderer::styled();
println!("{}", renderer.render(message));
}