Started Rust in Action MEAP.

4 files changed, 151 insertions, 0 deletions

diff --git a/meap/meap-code/ch10/ch10-sjlj/Cargo.toml b/meap/meap-code/ch10/ch10-sjlj/Cargo.toml
new file mode 100644
index 0000000..c9eab65
--- /dev/null
+++ b/meap/meap-code/ch10/ch10-sjlj/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "ch10-sjlj"
+version = "0.1.0"
+authors = ["Tim McNamara <code@timmcnamara.co.nz>"]
+
+[dependencies]
+libc = "0.2"
\ No newline at end of file
diff --git a/meap/meap-code/ch10/ch10-sjlj/Dockerfile b/meap/meap-code/ch10/ch10-sjlj/Dockerfile
new file mode 100644
index 0000000..ba5e1f0
--- /dev/null
+++ b/meap/meap-code/ch10/ch10-sjlj/Dockerfile
@@ -0,0 +1,37 @@
+# build strategy sourced from:

+# - https://www.fpcomplete.com/blog/2018/07/deploying-rust-with-docker-and-kubernetes

+# - http://whitfin.io/speeding-up-rust-docker-builds/

+

+# This image will build all dependencies before you

+# introducing the project's source code, which means

+# they'll be cached most of the time.

+

+FROM rust:latest as intermediate

+RUN rustup toolchain install nightly

+RUN rustup default nightly

+RUN rustup target add x86_64-unknown-linux-musl

+

+ENV PATH $PATH:/root/.cargo/bin

+ENV PKG_CONFIG_ALLOW_CROSS=1

+

+# fetch dependencies using a minimal project,

+# enabling the docker image to be cached with dependencies installed

+RUN USER=root cargo new --bin project

+WORKDIR /project

+

+COPY ./Cargo.lock ./Cargo.lock

+COPY ./Cargo.toml ./Cargo.toml

+

+#RUN cargo -v build --target x86_64-unknown-linux-musl

+

+# build actual project

+#RUN rm src/*.rs

+COPY ./src ./src

+RUN cargo +nightly -v check

+RUN cargo +nightly -v build --target x86_64-unknown-linux-musl

+RUN ls -R /project/target

+

+FROM alpine

+COPY --from=intermediate /project/target/x86_64-unknown-linux-musl/debug/ch10-sjlj /

+

+CMD /ch10-sjlj

diff --git a/meap/meap-code/ch10/ch10-sjlj/Makefile b/meap/meap-code/ch10/ch10-sjlj/Makefile
new file mode 100644
index 0000000..d68912d
--- /dev/null
+++ b/meap/meap-code/ch10/ch10-sjlj/Makefile
@@ -0,0 +1,2 @@
+container:

+    docker build -t ria-ch10-sjlj .
\ No newline at end of file
diff --git a/meap/meap-code/ch10/ch10-sjlj/src/main.rs b/meap/meap-code/ch10/ch10-sjlj/src/main.rs
new file mode 100644
index 0000000..baac669
--- /dev/null
+++ b/meap/meap-code/ch10/ch10-sjlj/src/main.rs
@@ -0,0 +1,105 @@
+#![feature(link_llvm_intrinsics)]
+#![allow(non_camel_case_types)]
+#![cfg(not(windows))]
+
+extern crate libc;
+
+use libc::{SIGUSR1, SIGALRM, SIGHUP, SIGQUIT, SIGTERM};
+use std::mem;
+
+const JMP_BUF_WIDTH: usize = mem::size_of::<usize>() * 8;
+type jmp_buf = [i8; JMP_BUF_WIDTH];
+
+static mut SHUT_DOWN: bool = false;
+static mut RETURN_HERE: jmp_buf = [0; JMP_BUF_WIDTH];
+const MOCK_SIGNAL_AT: usize = 3;
+
+extern "C" {
+    #[link_name = "llvm.setjmp"]
+    pub fn setjmp(a: *mut i8) -> i32;
+
+    #[link_name = "llvm.longjmp"]
+    pub fn longjmp(a: *mut i8, b: i32) -> ();
+}
+
+#[inline]
+fn ptr_to_jmp_buf() -> *mut i8 {
+    unsafe { &RETURN_HERE as *const i8 as *mut i8 }
+}
+
+#[inline]
+fn return_early() {
+    let franken_pointer = ptr_to_jmp_buf();
+    unsafe { longjmp(franken_pointer, 1) };
+}
+
+fn register_signal_handler() {
+    unsafe {
+        libc::signal(SIGUSR1, handle_signals as usize); // <4>
+    }
+}
+
+#[allow(dead_code)] // <5>
+fn handle_signals(sig: i32) {
+    register_signal_handler(); // Immediately re-registering the signal handler minimizes the chances of a missing a signal.
+
+    let should_shut_down = match sig {
+        SIGHUP => false,  // <7>
+        SIGALRM => false, // <7>
+        SIGTERM => true,  // <7>
+        SIGQUIT => true,  // <7>
+        SIGUSR1 => true,
+        _ => false, // <7>
+    };
+
+    unsafe {
+        // This unsafe block is required because we are modifying a global static variable.
+        SHUT_DOWN = should_shut_down;
+    }
+
+    return_early();
+}
+
+fn print_depth(depth: usize) {
+    for _ in 0..depth {
+        print!("#");
+    }
+    println!("");
+}
+
+fn dive(depth: usize, max_depth: usize) {
+    unsafe {
+        if SHUT_DOWN == true {
+            println!("!");
+            return;
+        }
+    }
+    print_depth(depth);
+
+    if depth >= max_depth {
+        return;
+    } else if depth == MOCK_SIGNAL_AT {
+        unsafe {
+            libc::raise(SIGUSR1);
+        }
+    } else {
+        dive(depth + 1, max_depth);
+    }
+    print_depth(depth);
+}
+
+fn main() {
+    const JUMP_SET: i32 = 0;
+
+    register_signal_handler();
+
+    let return_point = ptr_to_jmp_buf();
+    let rc = unsafe { setjmp(return_point) };
+    if rc == JUMP_SET {
+        dive(0, 10);
+    } else {
+        println!("early return!");
+    }
+
+    println!("finishing!")
+}