std: show signal number along with name

Author: notriddle

library/std/src/sys/unix/process/process_unix.rs

@@ -696,41 +696,46 @@ impl From<c_int> for ExitStatus {
 }
 
 /// Convert a signal number to a readable, searchable name.
-fn signal_string(signal: i32) -> String {
-    (match signal {
-        libc::SIGHUP => "SIGHUP",
-        libc::SIGINT => "SIGINT",
-        libc::SIGQUIT => "SIGQUIT",
-        libc::SIGILL => "SIGILL",
-        libc::SIGTRAP => "SIGTRAP",
-        libc::SIGABRT => "SIGABRT",
-        libc::SIGBUS => "SIGBUS",
-        libc::SIGFPE => "SIGFPE",
-        libc::SIGKILL => "SIGKILL",
-        libc::SIGUSR1 => "SIGUSR1",
-        libc::SIGSEGV => "SIGSEGV",
-        libc::SIGUSR2 => "SIGUSR2",
-        libc::SIGPIPE => "SIGPIPE",
-        libc::SIGALRM => "SIGALRM",
-        libc::SIGTERM => "SIGTERM",
-        libc::SIGCHLD => "SIGCHLD",
-        libc::SIGCONT => "SIGCONT",
-        libc::SIGSTOP => "SIGSTOP",
-        libc::SIGTSTP => "SIGTSTP",
-        libc::SIGTTIN => "SIGTTIN",
-        libc::SIGTTOU => "SIGTTOU",
-        libc::SIGURG => "SIGURG",
-        libc::SIGXCPU => "SIGXCPU",
-        libc::SIGXFSZ => "SIGXFSZ",
-        libc::SIGVTALRM => "SIGVTALRM",
-        libc::SIGPROF => "SIGPROF",
-        libc::SIGWINCH => "SIGWINCH",
-        libc::SIGIO => "SIGIO",
-        libc::SIGSYS => "SIGSYS",
+///
+/// This string should be displayed right after the signal number.
+/// If a signal is unrecognized, it returns the empty string, so that
+/// you just get the number like "0". If it is recognized, you'll get
+/// something like "9 (SIGKILL)".
+fn signal_string(signal: i32) -> &'static str {
+    match signal {
+        libc::SIGHUP => " (SIGHUP)",
+        libc::SIGINT => " (SIGINT)",
+        libc::SIGQUIT => " (SIGQUIT)",
+        libc::SIGILL => " (SIGILL)",
+        libc::SIGTRAP => " (SIGTRAP)",
+        libc::SIGABRT => " (SIGABRT)",
+        libc::SIGBUS => " (SIGBUS)",
+        libc::SIGFPE => " (SIGFPE)",
+        libc::SIGKILL => " (SIGKILL)",
+        libc::SIGUSR1 => " (SIGUSR1)",
+        libc::SIGSEGV => " (SIGSEGV)",
+        libc::SIGUSR2 => " (SIGUSR2)",
+        libc::SIGPIPE => " (SIGPIPE)",
+        libc::SIGALRM => " (SIGALRM)",
+        libc::SIGTERM => " (SIGTERM)",
+        libc::SIGCHLD => " (SIGCHLD)",
+        libc::SIGCONT => " (SIGCONT)",
+        libc::SIGSTOP => " (SIGSTOP)",
+        libc::SIGTSTP => " (SIGTSTP)",
+        libc::SIGTTIN => " (SIGTTIN)",
+        libc::SIGTTOU => " (SIGTTOU)",
+        libc::SIGURG => " (SIGURG)",
+        libc::SIGXCPU => " (SIGXCPU)",
+        libc::SIGXFSZ => " (SIGXFSZ)",
+        libc::SIGVTALRM => " (SIGVTALRM)",
+        libc::SIGPROF => " (SIGPROF)",
+        libc::SIGWINCH => " (SIGWINCH)",
+        libc::SIGIO => " (SIGIO)",
+        libc::SIGSYS => " (SIGSYS)",
         #[cfg(target_os = "linux")]
-        libc::SIGSTKFLT => "SIGSTKFLT",
+        libc::SIGSTKFLT => " (SIGSTKFLT)",
         #[cfg(target_os = "linux")]
-        libc::SIGPWR => "SIGPWR",
+        libc::SIGPWR => " (SIGPWR)",
         #[cfg(any(
             target_os = "macos",
             target_os = "ios",
@@ -740,7 +745,7 @@ fn signal_string(signal: i32) -> String {
             target_os = "openbsd",
             target_os = "dragonfly"
         ))]
-        libc::SIGEMT => "SIGEMT",
+        libc::SIGEMT => " (SIGEMT)",
         #[cfg(any(
             target_os = "macos",
             target_os = "ios",
@@ -750,26 +755,25 @@ fn signal_string(signal: i32) -> String {
             target_os = "openbsd",
             target_os = "dragonfly"
         ))]
-        libc::SIGINFO => "SIGINFO",
-        _ => return format!("{signal}"),
-    })
-    .to_string()
+        libc::SIGINFO => " (SIGINFO)",
+        _ => "",
+    }
 }
 
 impl fmt::Display for ExitStatus {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         if let Some(code) = self.code() {
             write!(f, "exit status: {code}")
         } else if let Some(signal) = self.signal() {
-            let signal = signal_string(signal);
+            let signal_string = signal_string(signal);
             if self.core_dumped() {
-                write!(f, "signal: {signal} (core dumped)")
+                write!(f, "signal: {signal}{signal_string} (core dumped)")
             } else {
-                write!(f, "signal: {signal}")
+                write!(f, "signal: {signal}{signal_string}")
             }
         } else if let Some(signal) = self.stopped_signal() {
-            let signal = signal_string(signal);
-            write!(f, "stopped (not terminated) by signal: {signal}")
+            let signal_string = signal_string(signal);
+            write!(f, "stopped (not terminated) by signal: {signal}{signal_string}")
         } else if self.continued() {
             write!(f, "continued (WIFCONTINUED)")
         } else {

library/std/src/sys/unix/process/process_unix/tests.rs

@@ -14,8 +14,8 @@ fn exitstatus_display_tests() {
 
     let t = |v, s| assert_eq!(s, format!("{}", <ExitStatus as ExitStatusExt>::from_raw(v)));
 
-    t(0x0000f, "signal: SIGTERM");
-    t(0x0008b, "signal: SIGSEGV (core dumped)");
+    t(0x0000f, "signal: 15 (SIGTERM)");
+    t(0x0008b, "signal: 11 (SIGSEGV) (core dumped)");
     t(0x00000, "exit status: 0");
     t(0x0ff00, "exit status: 255");
 
@@ -24,7 +24,7 @@ fn exitstatus_display_tests() {
     // The purpose of this test is to test our string formatting, not our understanding of the wait
     // status magic numbers.  So restrict these to Linux.
     if cfg!(target_os = "linux") {
-        t(0x0137f, "stopped (not terminated) by signal: SIGSTOP");
+        t(0x0137f, "stopped (not terminated) by signal: 19 (SIGSTOP)");
         t(0x0ffff, "continued (WIFCONTINUED)");
     }