Add libbacktrace support for Apple platforms

src/libbacktrace/configure

@@ -11844,6 +11844,9 @@ elf*) FORMAT_FILE="elf.lo" ;;
 pecoff) FORMAT_FILE="pecoff.lo"
         backtrace_supports_data=no
 	;;
+macho*) FORMAT_FILE="macho.lo"
+        backtrace_supports_data=no
+        ;;
 *) { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: could not determine output file type" >&5
 $as_echo "$as_me: WARNING: could not determine output file type" >&2;}
    FORMAT_FILE="unknown.lo"

src/libbacktrace/configure.ac

@@ -231,6 +231,9 @@ elf*) FORMAT_FILE="elf.lo" ;;
 pecoff) FORMAT_FILE="pecoff.lo"
         backtrace_supports_data=no
 	;;
+macho*) FORMAT_FILE="macho.lo"
+        backtrace_supports_data=no
+        ;;
 *) AC_MSG_WARN([could not determine output file type])
    FORMAT_FILE="unknown.lo"
    backtrace_supported=no

src/libbacktrace/filetype.awk

@@ -3,3 +3,9 @@
 /\177ELF\002/ { if (NR == 1) { print "elf64"; exit } }
 /\114\001/    { if (NR == 1) { print "pecoff"; exit } }
 /\144\206/    { if (NR == 1) { print "pecoff"; exit } }
+/\xFE\xED\xFA\xCE/ { if (NR == 1) { print "macho32"; exit } }
+/\xCE\xFA\xED\xFE/ { if (NR == 1) { print "macho32"; exit } }
+/\xFE\xED\xFA\xCF/ { if (NR == 1) { print "macho64"; exit } }
+/\xCF\xFA\xED\xFE/ { if (NR == 1) { print "macho64"; exit } }
+/\xCA\xFE\xBA\xBE/ { if (NR == 1) { print "macho-fat"; exit } }
+/\xBE\xBA\xFE\xCA/ { if (NR == 1) { print "macho-fat"; exit } }

src/libstd/build.rs

@@ -20,7 +20,7 @@ use build_helper::{run, native_lib_boilerplate};
 fn main() {
     let target = env::var("TARGET").expect("TARGET was not set");
     let host = env::var("HOST").expect("HOST was not set");
-    if cfg!(feature = "backtrace") && !target.contains("apple") && !target.contains("msvc") &&
+    if cfg!(feature = "backtrace") && !target.contains("msvc") &&
         !target.contains("emscripten") && !target.contains("fuchsia") {
         let _ = build_libbacktrace(&host, &target);
     }

src/libstd/sys/unix/backtrace/mod.rs

@@ -91,15 +91,42 @@ mod tracing;
 // symbol resolvers:
 mod printing;
 
-#[cfg(not(any(target_os = "macos", target_os = "ios", target_os = "emscripten")))]
+#[cfg(not(target_os = "emscripten"))]
 pub mod gnu {
     use io;
     use fs;
     use libc::c_char;
 
+    #[cfg(not(any(target_os = "macos", target_os = "ios")))]
     pub fn get_executable_filename() -> io::Result<(Vec<c_char>, fs::File)> {
         Err(io::Error::new(io::ErrorKind::Other, "Not implemented"))
     }
+
+    #[cfg(any(target_os = "macos", target_os = "ios"))]
+    pub fn get_executable_filename() -> io::Result<(Vec<c_char>, fs::File)> {
+        use ptr;
+        use slice;
+        use ffi::OsStr;
+        use os::unix::ffi::OsStrExt;
+        use libc::c_int;
+
+        extern {
+            fn _NSGetExecutablePath(buf: *mut c_char,
+                                    bufsize: *mut u32) -> c_int;
+        }
+        unsafe {
+            let mut bufsize: u32 = 0;
+            _NSGetExecutablePath(ptr::null_mut(), &mut bufsize);
+            if bufsize == 0 { return Err(io::Error::last_os_error()); }
+            let mut buffer: Vec<c_char> = Vec::with_capacity(bufsize as usize);
+            let ret = _NSGetExecutablePath(buffer.as_mut_ptr(), &mut bufsize);
+            if ret != 0 { return Err(io::Error::last_os_error()); }
+            buffer.set_len(bufsize as usize);
+            let file = fs::File::open(OsStr::from_bytes(
+                    slice::from_raw_parts(buffer.as_ptr() as *const u8, buffer.len()-1)))?;
+            Ok((buffer, file))
+        }
+    }
 }
 
 pub struct BacktraceContext;

src/libstd/sys/unix/backtrace/printing/mod.rs

@@ -10,13 +10,11 @@
 
 pub use self::imp::{foreach_symbol_fileline, resolve_symname};
 
-#[cfg(any(target_os = "macos", target_os = "ios",
-          target_os = "emscripten"))]
+#[cfg(target_os = "emscripten")]
 #[path = "dladdr.rs"]
 mod imp;
 
-#[cfg(not(any(target_os = "macos", target_os = "ios",
-              target_os = "emscripten")))]
+#[cfg(not(target_os = "emscripten"))]
 mod imp {
     pub use sys_common::gnu::libbacktrace::{foreach_symbol_fileline, resolve_symname};
 }

src/libstd/sys_common/mod.rs

@@ -51,7 +51,7 @@ pub use sys::net;
 pub mod net;
 
 #[cfg(feature = "backtrace")]
-#[cfg(any(all(unix, not(any(target_os = "macos", target_os = "ios", target_os = "emscripten"))),
+#[cfg(any(all(unix, not(target_os = "emscripten")),
           all(windows, target_env = "gnu"),
           target_os = "redox"))]
 pub mod gnu;