Expose libssh2_trace function (#209)

* Expose libssh2_trace function and associated
constants, to allow enabling libssh2 trace
output.

* set LIBSSH2_WIN32 on windows build so that
gettimeofday replacement will be compiled.

* libssh2_trace actually returns int, even though
the documentation says it returns void. This
was causing systest to fail.
Changed the FFI to match the C function.

Co-authored-by: eharmic <michael.harris@ericsson.com>

4 files changed, 51 insertions, 1 deletions

diff --git a/libssh2-sys/build.rs b/libssh2-sys/build.rs
index 2150148..0ec2073 100644
--- a/libssh2-sys/build.rs
+++ b/libssh2-sys/build.rs
@@ -39,6 +39,7 @@ fn main() {
     }
 
     let target = env::var("TARGET").unwrap();
+    let profile = env::var("PROFILE").unwrap();
     let dst = PathBuf::from(env::var_os("OUT_DIR").unwrap());
     let mut cfg = cc::Build::new();
 
@@ -91,6 +92,7 @@ fn main() {
     if target.contains("windows") {
         cfg.include("libssh2/win32");
         cfg.define("LIBSSH2_WINCNG", None);
+        cfg.define("LIBSSH2_WIN32", None);
         cfg.file("libssh2/src/wincng.c");
     } else {
         cfg.flag("-fvisibility=hidden");
@@ -108,6 +110,7 @@ fn main() {
         cfg.define("HAVE_LIBCRYPT32", None);
         cfg.define("HAVE_EVP_AES_128_CTR", None);
         cfg.define("HAVE_POLL", None);
+        cfg.define("HAVE_GETTIMEOFDAY", None);
 
         cfg.file("libssh2/src/openssl.c");
 
@@ -126,6 +129,11 @@ fn main() {
     cfg.define("LIBSSH2_DH_GEX_NEW", None);
 
     cfg.define("LIBSSH2_HAVE_ZLIB", None);
+
+    if profile.contains("debug") {
+        cfg.define("LIBSSH2DEBUG", None);
+    }
+    
     println!("cargo:rerun-if-env-changed=DEP_Z_INCLUDE");
     if let Some(path) = env::var_os("DEP_Z_INCLUDE") {
         cfg.include(path);
diff --git a/libssh2-sys/lib.rs b/libssh2-sys/lib.rs
index ad36642..8186fd7 100644
--- a/libssh2-sys/lib.rs
+++ b/libssh2-sys/lib.rs
@@ -188,6 +188,15 @@ pub const LIBSSH2_CHANNEL_EXTENDED_DATA_MERGE: c_int = 2;
 pub const LIBSSH2_SESSION_BLOCK_INBOUND: c_int = 1;
 pub const LIBSSH2_SESSION_BLOCK_OUTBOUND: c_int = 2;
 
+pub const  LIBSSH2_TRACE_TRANS : c_int = 1<<1;
+pub const  LIBSSH2_TRACE_KEX   : c_int = 1<<2;
+pub const  LIBSSH2_TRACE_AUTH  : c_int = 1<<3;
+pub const  LIBSSH2_TRACE_CONN  : c_int = 1<<4;
+pub const  LIBSSH2_TRACE_SCP   : c_int = 1<<5;
+pub const  LIBSSH2_TRACE_SFTP  : c_int = 1<<6;
+pub const  LIBSSH2_TRACE_ERROR : c_int = 1<<7;
+pub const  LIBSSH2_TRACE_PUBLICKEY : c_int = 1<<8;
+pub const  LIBSSH2_TRACE_SOCKET : c_int = 1<<9;
 pub enum LIBSSH2_SESSION {}
 pub enum LIBSSH2_AGENT {}
 pub enum LIBSSH2_CHANNEL {}
@@ -310,6 +319,7 @@ extern "C" {
     pub fn libssh2_exit();
     pub fn libssh2_free(sess: *mut LIBSSH2_SESSION, ptr: *mut c_void);
     pub fn libssh2_hostkey_hash(session: *mut LIBSSH2_SESSION, hash_type: c_int) -> *const c_char;
+    pub fn libssh2_trace(session: *mut LIBSSH2_SESSION, bitmask: c_int) -> c_int;
 
     // session
     pub fn libssh2_session_init_ex(
diff --git a/src/lib.rs b/src/lib.rs
index 47467c7..45f8e6b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -233,7 +233,7 @@ pub use error::{Error, ErrorCode};
 pub use knownhosts::{Host, KnownHosts};
 pub use listener::Listener;
 use session::SessionInner;
-pub use session::{BlockDirections, KeyboardInteractivePrompt, Prompt, ScpFileStat, Session};
+pub use session::{BlockDirections, KeyboardInteractivePrompt, Prompt, ScpFileStat, Session, TraceFlags};
 pub use sftp::{File, FileStat, FileType, OpenType};
 pub use sftp::{OpenFlags, RenameFlags, Sftp};
 pub use DisconnectCode::{AuthCancelledByUser, TooManyConnections};
diff --git a/src/session.rs b/src/session.rs
index 33bb619..a1fa674 100644
--- a/src/session.rs
+++ b/src/session.rs
@@ -18,6 +18,31 @@ use util;
 use {raw, ByApplication, DisconnectCode, Error, ErrorCode, HostKeyType};
 use {Agent, Channel, HashType, KnownHosts, Listener, MethodType, Sftp};
 
+bitflags! {
+    /// Flags which can be used with the session trace method to set
+    /// the trace level.
+    pub struct TraceFlags: c_int {
+        /// Authentication debugging
+        const AUTH      = raw::LIBSSH2_TRACE_AUTH;
+        /// Connection layer debugging
+        const CONN      = raw::LIBSSH2_TRACE_CONN;
+        /// Error debugging
+        const ERROR     = raw::LIBSSH2_TRACE_ERROR;
+        /// Key exchange debugging
+        const KEX       = raw::LIBSSH2_TRACE_KEX;
+        /// Public Key Debugging
+        const PUBLICKEY = raw::LIBSSH2_TRACE_PUBLICKEY;
+        /// SCP debugging
+        const SCP       = raw::LIBSSH2_TRACE_SCP;
+        /// SFTP debugging
+        const SFTP      = raw::LIBSSH2_TRACE_SFTP;
+        /// Socket low-level debugging
+        const SOCKET    = raw::LIBSSH2_TRACE_SOCKET;
+        /// Transport layer debugging
+        const TRANS     = raw::LIBSSH2_TRACE_TRANS;
+    }
+}
+
 /// Called by libssh2 to respond to some number of challenges as part of
 /// keyboard interactive authentication.
 pub trait KeyboardInteractivePrompt {
@@ -1002,6 +1027,13 @@ impl Session {
     fn inner(&self) -> MutexGuard<SessionInner> {
         self.inner.lock()
     }
+
+    /// Sets the trace level for the session.
+    ///
+    pub fn trace(&self, bitmask: TraceFlags) {
+        let inner = self.inner();
+        unsafe { let _ = raw::libssh2_trace(inner.raw, bitmask.bits() as c_int); }
+    }
 }
 
 #[cfg(unix)]