Fix Instances of Memory Corruption on Illumos

TESTING.md

@@ -2,6 +2,72 @@
 
 This file outlines the regression testing plan for all platforms.
 
+## Linux / Fedora Silverblue
+
+## Linux / Ubuntu
+
+## Windows
+
+## MacOS
+
+## FreeBSD
+
+## Illumos
+
+Testing is done on Tribblix (virtualized on Fedora Silverblue):
+
+<http://www.tribblix.org/download.html>
+
+Download the 64-bit x86/x64 standard image.
+
+Install it in GNOME Boxes (select operating system OpenIndiana Hipster).
+
+Set 4 GiB memory, and 16 GiB Storage limit
+
+Login as `jack` (password `jack`)
+
+```shell
+su - root # password `tribblix`
+format # 0, quit
+./live_install -G c1t0d0 develop # replace c1t0d0 with disk
+reboot -p
+```
+
+Login as `jack` (password `jack`)
+
+Now, install Rust (use bash instead of sh, sh doesn't work)
+
+```shell
+curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | bash # 1
+source "$HOME/.cargo/env"
+```
+
+### Testing
+
+```shell
+git clone https://github.com/ardaku/whoami.git
+cd whoami
+# run both debug and release
+cargo run --example whoami-demo
+cargo run --example whoami-demo --release
+```
+
+Expected output is
+
+```console
+WhoAmI 1.5.0-pre.0
+
+User's Language        whoami::langs():               
+User's Name            whoami::realname():            Tribblix Jack
+User's Username        whoami::username():            jack
+Device's Pretty Name   whoami::devicename():          tribblix
+Device's Hostname      whoami::fallible::hostname():  tribblix
+Device's Platform      whoami::platform():            Illumos
+Device's OS Distro     whoami::distro():              Tribblix
+Device's Desktop Env.  whoami::desktop_env():         Unknown: Unknown
+Device's CPU Arch      whoami::arch():                Unknown: i86pc
+```
+
 ## Redox
 
 <https://doc.redox-os.org/book/ch08-01-advanced-build.html#understanding-cross-compilation-for-redox>

src/os/unix.rs

@@ -29,7 +29,8 @@ use crate::{
     target_os = "dragonfly",
     target_os = "bitrig",
     target_os = "openbsd",
-    target_os = "netbsd"
+    target_os = "netbsd",
+    target_os = "illumos",
 )))]
 #[repr(C)]
 struct PassWd {
@@ -65,6 +66,31 @@ struct PassWd {
     pw_fields: i32,
 }
 
+#[cfg(target_os = "illumos")]
+#[repr(C)]
+struct PassWd {
+    pw_name: *const c_void,
+    pw_passwd: *const c_void,
+    pw_uid: u32,
+    pw_gid: u32,
+    pw_age: *const c_void,
+    pw_comment: *const c_void,
+    pw_gecos: *const c_void,
+    pw_dir: *const c_void,
+    pw_shell: *const c_void,
+}
+
+#[cfg(target_os = "illumos")]
+extern "system" {
+    fn getpwuid_r(
+        uid: u32,
+        pwd: *mut PassWd,
+        buf: *mut c_void,
+        buflen: c_int,
+    ) -> *mut PassWd;
+}
+
+#[cfg(not(target_os = "illumos"))]
 extern "system" {
     fn getpwuid_r(
         uid: u32,
@@ -73,6 +99,9 @@ extern "system" {
         buflen: usize,
         result: *mut *mut PassWd,
     ) -> i32;
+}
+
+extern "system" {
     fn geteuid() -> u32;
     fn gethostname(name: *mut c_void, len: usize) -> i32;
 }
@@ -204,22 +233,41 @@ fn getpwuid(name: Name) -> Result<OsString> {
 
     // Get PassWd `struct`.
     let passwd = unsafe {
-        let ret = getpwuid_r(
-            geteuid(),
-            passwd.as_mut_ptr(),
-            buffer.as_mut_ptr() as *mut c_void,
-            BUF_SIZE,
-            _passwd.as_mut_ptr(),
-        );
-
-        if ret != 0 {
-            return Err(Error::last_os_error());
+        #[cfg(not(target_os = "illumos"))]
+        {
+            let ret = getpwuid_r(
+                geteuid(),
+                passwd.as_mut_ptr(),
+                buffer.as_mut_ptr() as *mut c_void,
+                BUF_SIZE,
+                _passwd.as_mut_ptr(),
+            );
+
+            if ret != 0 {
+                return Err(Error::last_os_error());
+            }
+
+            let _passwd = _passwd.assume_init();
+
+            if _passwd.is_null() {
+                return Err(super::err_null_record());
+            }
         }
 
-        let _passwd = _passwd.assume_init();
+        #[cfg(target_os = "illumos")]
+        {
+            use std::convert::TryInto;
+
+            let ret = getpwuid_r(
+                geteuid(),
+                passwd.as_mut_ptr(),
+                buffer.as_mut_ptr() as *mut c_void,
+                BUF_SIZE.try_into().unwrap_or(c_int::MAX),
+            );
 
-        if _passwd.is_null() {
-            return Err(super::err_null_record());
+            if ret.is_null() {
+                return Err(Error::last_os_error());
+            }
         }
 
         passwd.assume_init()
@@ -344,7 +392,6 @@ pub(crate) fn lang() -> impl Iterator<Item = String> {
     target_os = "freebsd",
     target_os = "netbsd",
     target_os = "openbsd",
-    target_os = "illumos"
 ))]
 #[repr(C)]
 struct UtsName {
@@ -355,6 +402,16 @@ struct UtsName {
     machine: [c_char; 256],
 }
 
+#[cfg(target_os = "illumos")]
+#[repr(C)]
+struct UtsName {
+    sysname: [c_char; 257],
+    nodename: [c_char; 257],
+    release: [c_char; 257],
+    version: [c_char; 257],
+    machine: [c_char; 257],
+}
+
 #[cfg(target_os = "dragonfly")]
 #[repr(C)]
 struct UtsName {