Added a userdata generic pointer to the log callback function.

include/libssh/libssh.h

@@ -376,6 +376,9 @@ LIBSSH_API int channel_get_exit_status(ssh_channel channel);
 typedef int (*ssh_auth_callback) (const char *prompt, char *buf, size_t len,
     int echo, int verify, void *userdata);
 
+typedef void (*ssh_log_callback) (ssh_session session, int priority,
+    const char *message, void *userdata);
+
 LIBSSH_API SSH_OPTIONS *ssh_options_new(void);
 LIBSSH_API SSH_OPTIONS *ssh_options_copy(SSH_OPTIONS *opt);
 LIBSSH_API void ssh_options_free(SSH_OPTIONS *opt);
@@ -396,7 +399,7 @@ LIBSSH_API int ssh_options_set_timeout(SSH_OPTIONS *opt, long seconds, long usec
 LIBSSH_API int ssh_options_allow_ssh1(SSH_OPTIONS *opt, int allow);
 LIBSSH_API int ssh_options_allow_ssh2(SSH_OPTIONS *opt, int allow);
 LIBSSH_API int ssh_options_set_log_function(SSH_OPTIONS *opt,
-    void (*callback)(const char *message, SSH_SESSION *session, int verbosity));
+    ssh_log_callback cb, void *userdata);
 LIBSSH_API int ssh_options_set_log_verbosity(SSH_OPTIONS *opt, int verbosity);
 LIBSSH_API int ssh_options_set_dsa_server_key(SSH_OPTIONS *opt, const char *dsakey);
 LIBSSH_API int ssh_options_set_rsa_server_key(SSH_OPTIONS *opt, const char *rsakey);

include/libssh/priv.h

@@ -296,7 +296,8 @@ struct ssh_options_struct {
     char *dsakey;
     char *rsakey; /* host key for server implementation */
     int log_verbosity;
-    void (*log_function)(const char *message, SSH_SESSION *session, int verbosity); //log callback
+    ssh_log_callback log_function; //log callback
+    void *log_userdata;
 };
 
 typedef struct ssh_crypto_struct {

libssh/log.c

@@ -56,7 +56,8 @@ void ssh_log(SSH_SESSION *session, int verbosity, const char *format, ...) {
     va_end(va);
 
     if (session->options->log_function) {
-      session->options->log_function(buffer, session, verbosity);
+      session->options->log_function(session, verbosity, buffer,
+          session->options->log_userdata);
     } else if (verbosity == SSH_LOG_FUNCTIONS) {
       if (session->log_indent > 255) {
         min = 255;

libssh/options.c

@@ -762,13 +762,14 @@ int ssh_options_allow_ssh2(SSH_OPTIONS *opt, int allow) {
  *
  * @warning The message string may contain format string characters.
  */
-int ssh_options_set_log_function(SSH_OPTIONS *opt,
-    void (*callback)(const char *message, SSH_SESSION *session, int priority)) {
-  if (opt == NULL || callback == NULL) {
+int ssh_options_set_log_function(SSH_OPTIONS *opt, ssh_log_callback cb,
+      void *userdata) {
+  if (opt == NULL || cb == NULL) {
     return -1;
   }
 
-  opt->log_function = callback;
+  opt->log_function = cb;
+  opt->log_userdata = userdata;
 
   return 0;
 }