Started Rust in Action MEAP.

1 files changed, 48 insertions, 0 deletions

diff --git a/meap/meap-code/ch10/ch10-handle/src/main.rs b/meap/meap-code/ch10/ch10-handle/src/main.rs
new file mode 100644
index 0000000..d40e329
--- /dev/null
+++ b/meap/meap-code/ch10/ch10-handle/src/main.rs
@@ -0,0 +1,48 @@
+extern crate libc; // 0.2.42
+
+use std::time::{Duration};
+use std::thread::{sleep};
+use libc::{signal,raise};
+use libc::{SIG_DFL, SIG_IGN, SIGTERM, SIGHUP};
+
+type handler_ptr = extern "C" fn(i32) -> ();
+
+static mut ABORT: bool = false;
+
+#[inline(never)]
+extern "C" fn handle_signals(sig: i32) { // rustc will warn that that this code is never run
+    let handle_signals_ptr: handler_ptr = handle_signals;
+    unsafe { // set the signal handler again, to prevent it resetting to SIG_DFL
+        signal(SIGTERM, std::mem::transmute(handle_signals_ptr));
+    }
+    
+    let should_abort = match sig {
+        SIGTERM => true,
+        SIGHUP => false,
+        _ => false,
+    };
+    
+    unsafe { // make a quick update here, and defer the real work to somewhere else
+        ABORT = should_abort;
+    }
+} 
+
+fn main() {
+    let delay = Duration::from_secs(1);
+
+    // "main loop"
+    for i in 1..=60 {
+        unsafe { // at every step, check to see if a signal has been sent
+            if ABORT {
+                break;
+            }
+        }
+
+        sleep(delay);
+        println!(". {}", i);
+        
+        if i > 2 {
+            unsafe { raise(SIGTERM); }
+        }
+    }
+}
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