Use bindgen for OSX bindings

Manually written library bindings turn out to be fragile in the event
that the the underlying library is updated. We have no control over
the user's systems, so we cannot assume that the bindings we write
will remain valid forever.

This change introduces bindgen to create rust bindings using
headers from the system on which the package is built.

Author: akhramov

.gitignore

@@ -1,3 +1,4 @@
 .idea
 target
 Cargo.lock
+src/osx_libproc_bindings.rs

Cargo.toml

@@ -29,3 +29,6 @@ path = "src/procinfo.rs"
 [[bin]]
 name = "dmesg"
 path = "src/dmesg.rs"
+
+[build-dependencies]
+bindgen = "0.53.1"

build.rs

@@ -0,0 +1,14 @@
+#[cfg(target_os = "macos")]
+fn main() {
+    let bindings = bindgen::builder()
+        .header_contents("libproc_rs.h", "#include <libproc.h>")
+        .generate()
+        .expect("Failed to build libproc bindings");
+
+    bindings
+        .write_to_file("src/osx_libproc_bindings.rs")
+        .expect("Failed to write libproc bindings");
+}
+
+#[cfg(not(target_os = "macos"))]
+fn main() {}

src/lib.rs

@@ -9,4 +9,7 @@
 extern crate libc;
 extern crate errno;
 
-pub mod libproc;
+pub mod libproc;
+#[cfg(target_os = "macos")]
+#[allow(warnings, missing_docs)]
+mod osx_libproc_bindings;

src/libproc/bsd_info.rs

@@ -1,62 +1,6 @@
-extern crate libc;
-
-use self::libc::{c_char, uid_t, gid_t};
-
 use crate::libproc::proc_pid::{PIDInfo, PidInfoFlavor};
-
-// from http://opensource.apple.com//source/xnu/xnu-1504.7.4/bsd/sys/param.h
-const MAXCOMLEN	: usize = 16;
-
-/// Struct for BSDInfo about a process
-#[repr(C)]
-#[derive(Default)]
-pub struct BSDInfo {
-    /// 64bit; emulated etc
-    pub pbi_flags               : u32,
-    /// status
-    pub pbi_status              : u32,
-    /// x status
-    pub pbi_xstatus             : u32,
-    /// PID
-    pub pbi_pid                 : u32,
-    /// PPID
-    pub pbi_ppid                : u32,
-    /// UID - User ID
-    pub pbi_uid                 : uid_t,
-    /// GID - Group ID
-    pub pbi_gid                 : gid_t,
-    /// RUID
-    pub pbi_ruid                : uid_t,
-    /// RGID
-    pub pbi_rgid                : gid_t,
-    /// RGID
-    pub pbi_svuid               : uid_t,
-    /// SVUID
-    pub pbi_svgid               : gid_t,
-    /// reserved for future use
-    pub rfu_1                   : u32,
-    /// Comm
-    pub pbi_comm                : [c_char; MAXCOMLEN],
-    /// empty if no name is registered
-    pub pbi_name                : [c_char; 2 * MAXCOMLEN],
-    /// nfile - Number of files
-    pub pbi_nfiles              : u32,
-    /// PGID
-    pub pbi_pgid                : u32,
-    /// PJOBC
-    pub pbi_pjobc               : u32,
-    /// controlling tty dev
-    pub e_tdev                  : u32,
-    /// tty process group id
-    pub e_tpgid                 : u32,
-    /// Nice
-    pub pbi_nice                : u32,
-    /// Start tv sec
-    pub pbi_start_tvsec         : u64,
-    /// Start tv micro sec
-    pub pbi_start_tvusec        : u64
-}
+pub use crate::osx_libproc_bindings::proc_bsdinfo as BSDInfo;
 
 impl PIDInfo for BSDInfo {
     fn flavor() -> PidInfoFlavor { PidInfoFlavor::TBSDInfo }
-}
+}

src/libproc/file_info.rs

@@ -6,16 +6,9 @@ use crate::libproc::helpers;
 use crate::libproc::proc_pid::{ListPIDInfo, PidInfoFlavor};
 
 #[cfg(target_os = "macos")]
-use self::libc::{c_int, c_void};
-
-// this extern block links to the libproc library
-// Original signatures of functions can be found at http://opensource.apple.com/source/Libc/Libc-594.9.4/darwin/libproc.c
+use self::libc::c_void;
 #[cfg(target_os = "macos")]
-#[link(name = "proc", kind = "dylib")]
-extern {
-    // This method is supported in the minimum version of Mac OS X which is 10.5
-    fn proc_pidfdinfo(pid: c_int, fd: c_int, flavor: c_int, buffer: *mut c_void, buffersize: c_int) -> c_int;
-}
+use crate::osx_libproc_bindings::proc_pidfdinfo;
 
 /// Flavor of Pid FileDescriptor info for different types of File Descriptors
 pub enum PIDFDInfoFlavor {

src/libproc/kmesg_buffer.rs

@@ -5,7 +5,7 @@ extern crate libc;
 use std::str;
 
 #[cfg(target_os = "macos")]
-use self::libc::{c_int, c_void};
+use self::libc::c_void;
 
 #[cfg(target_os = "linux")]
 use std::fs::File;
@@ -18,18 +18,8 @@ use std::sync::mpsc::Receiver;
 #[cfg(target_os = "linux")]
 use std::{thread, time};
 
-// See https://opensource.apple.com/source/xnu/xnu-1456.1.26/bsd/sys/msgbuf.h
 #[cfg(target_os = "macos")]
-const MAX_MSG_BSIZE: usize = 1024 * 1024;
-
-// this extern block links to the libproc library
-// Original signatures of functions can be found at http://opensource.apple.com/source/Libc/Libc-594.9.4/darwin/libproc.c
-#[cfg(target_os = "macos")]
-#[link(name = "proc", kind = "dylib")]
-extern {
-    // This method is supported in the minimum version of Mac OS X which is 10.5
-    fn proc_kmsgbuf(buffer: *mut c_void, buffersize: u32) -> c_int;
-}
+use crate::osx_libproc_bindings::{MAXBSIZE as MAX_MSG_BSIZE, proc_kmsgbuf};
 
 /// Get the contents of the kernel message buffer
 ///
@@ -39,7 +29,7 @@ extern {
 /// See http://opensource.apple.com//source/system_cmds/system_cmds-336.6/dmesg.tproj/dmesg.c// See http://opensource.apple.com//source/system_cmds/system_cmds-336.6/dmesg.tproj/dmesg.c
 #[cfg(target_os = "macos")]
 pub fn kmsgbuf() -> Result<String, String> {
-    let mut message_buffer: Vec<u8> = Vec::with_capacity(MAX_MSG_BSIZE);
+    let mut message_buffer: Vec<u8> = Vec::with_capacity(MAX_MSG_BSIZE as _);
     let buffer_ptr = message_buffer.as_mut_ptr() as *mut c_void;
     let ret: i32;
 

src/libproc/mod.rs

@@ -13,10 +13,13 @@ pub mod kmesg_buffer;
 /// Information about Work Queues - very MacOS specific
 pub mod work_queue_info;
 /// Information about Threads running inside processes
+#[cfg(target_os = "macos")]
 pub mod thread_info;
 /// Information about Tasks - very MacOS specific
+#[cfg(target_os = "macos")]
 pub mod task_info;
 /// BSD specific information - very MacOS specific
+#[cfg(target_os = "macos")]
 pub mod bsd_info;
 /// Information about Process Resource Usage - added in Mac OS X 10.9
 pub mod pid_rusage;
@@ -28,4 +31,4 @@ pub mod file_info;
 #[cfg(target_os = "macos")]
 pub mod net_info;
 
-mod helpers;
+mod helpers;

src/libproc/pid_rusage.rs

@@ -4,10 +4,12 @@ extern crate libc;
 use crate::libproc::helpers;
 
 #[cfg(target_os = "macos")]
-use self::libc::{c_void, c_int};
+use self::libc::c_void;
 
 #[cfg(target_os = "linux")]
 use crate::libproc::helpers::{procfile_field, parse_memory_string};
+#[cfg(target_os = "macos")]
+use crate::osx_libproc_bindings::proc_pid_rusage;
 
 /// The `PIDRUsage` trait is needed for polymorphism on pidrusage types, also abstracting flavor in order to provide
 /// type-guaranteed flavor correctness
@@ -34,13 +36,6 @@ pub enum PidRUsageFlavor {
     V4 = 4,
 }
 
-// this extern block links to the libproc library
-// Original signatures of functions can be found at http://opensource.apple.com/source/Libc/Libc-594.9.4/darwin/libproc.c
-#[cfg(target_os = "macos")]
-#[link(name = "proc", kind = "dylib")]
-extern {
-    fn proc_pid_rusage(pid: c_int, flavor: c_int, buffer: *mut c_void) -> c_int;
-}
 
 /// C struct for Resource Usage Version 0
 #[repr(C)]
@@ -381,7 +376,7 @@ pub fn pidrusage<T: PIDRUsage>(pid : i32) -> Result<T, String> {
     let ret: i32;
 
     unsafe {
-        ret = proc_pid_rusage(pid, flavor, buffer_ptr);
+        ret = proc_pid_rusage(pid, flavor, buffer_ptr as _);
     };
 
     if ret < 0 {
@@ -427,4 +422,4 @@ mod test {
         let usage: RUsageInfoV0 = pidrusage(std::process::id() as i32).expect("pidrusage() failed");
         assert!(usage.ri_resident_size > 0, "Resident size reports 0")
     }
-}
+}