diff --git a/libssh/channels1.c b/libssh/channels1.c
index 9a827e39..6a7a3f26 100644
--- a/libssh/channels1.c
+++ b/libssh/channels1.c
@@ -4,6 +4,7 @@
  * This file is part of the SSH Library
  *
  * Copyright (c) 2003-2008 by Aris Adamantiadis
+ * Copyright (c) 2009      by Andreas Schneider <mail@cynapses.org>
  *
  * The SSH Library is free software; you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published by
@@ -68,156 +69,257 @@ int channel_open_session1(CHANNEL *chan){
  */
 
 int channel_request_pty_size1(CHANNEL *channel, char *terminal, int col,
-        int row){
-    STRING *str;
-    SSH_SESSION *session=channel->session;
-    str=string_from_char(terminal);
-    buffer_add_u8(session->out_buffer,SSH_CMSG_REQUEST_PTY);
-    buffer_add_ssh_string(session->out_buffer,str);
-    free(str);
-    buffer_add_u32(session->out_buffer,ntohl(row));
-    buffer_add_u32(session->out_buffer,ntohl(col));
-    buffer_add_u32(session->out_buffer,0); /* x */
-    buffer_add_u32(session->out_buffer,0); /* y */
-    buffer_add_u8(session->out_buffer,0); /* tty things */
-    ssh_log(session, SSH_LOG_FUNCTIONS, "Opening a ssh1 pty");
-    if(packet_send(session))
-        return -1;
-    if(packet_read(session))
-        return -1;
-    if(packet_translate(session))
-        return -1;
-    switch (session->in_packet.type){
-        case SSH_SMSG_SUCCESS:
-            ssh_log(session, SSH_LOG_RARE, "pty: Success");
-            return 0;
-            break;
-        case SSH_SMSG_FAILURE:
-            ssh_set_error(session,SSH_REQUEST_DENIED,
-                    "Server denied PTY allocation");
-            ssh_log(session, SSH_LOG_RARE, "pty : denied\n");
-            break;
-        default:
-            ssh_log(session, SSH_LOG_RARE, "pty : error\n");
-            ssh_set_error(session,SSH_FATAL,
-                    "Received unexpected packet type %d",
-                    session->in_packet.type);
-            return -1;
-    }
+    int row) {
+  SSH_SESSION *session = channel->session;
+  STRING *str = NULL;
+
+  str = string_from_char(terminal);
+  if (str == NULL) {
     return -1;
-}
+  }
 
-int channel_change_pty_size1(CHANNEL *channel, int cols, int rows){
-    SSH_SESSION *session=channel->session;
-    buffer_add_u8(session->out_buffer,SSH_CMSG_WINDOW_SIZE);
-    buffer_add_u32(session->out_buffer,ntohl(rows));
-    buffer_add_u32(session->out_buffer,ntohl(cols));
-    buffer_add_u32(session->out_buffer,0);
-    buffer_add_u32(session->out_buffer,0);
-    if(packet_send(session))
-        return -1;
-    ssh_log(session, SSH_LOG_RARE, "Change pty size send");
-    packet_wait(session,SSH_SMSG_SUCCESS,1);
-    switch (session->in_packet.type){
-        case SSH_SMSG_SUCCESS:
-            ssh_log(session, SSH_LOG_RARE, "pty size changed");
-            return 0;
-            break;
-        case SSH_SMSG_FAILURE:
-            ssh_log(session, SSH_LOG_RARE, "pty size change denied");
-            ssh_set_error(session,SSH_REQUEST_DENIED,"pty size change denied");
-            return -1;
-    }
-    ssh_set_error(session,SSH_FATAL,"Received unexpected packet type %d",
-            session->in_packet.type);
+  if (buffer_add_u8(session->out_buffer, SSH_CMSG_REQUEST_PTY) < 0) {
+    string_free(str);
     return -1;
+  }
+  if (buffer_add_ssh_string(session->out_buffer, str) < 0) {
+    string_free(str);
+    return -1;
+  }
+  string_free(str);
+
+  if (buffer_add_u32(session->out_buffer, ntohl(row)) < 0) {
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, ntohl(col)) < 0) {
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, 0) < 0) { /* x */
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, 0) < 0) { /* y */
+    return -1;
+  }
+  if (buffer_add_u8(session->out_buffer, 0); < 0) { /* tty things */
+    return -1;
+  }
+
+  ssh_log(session, SSH_LOG_FUNCTIONS, "Opening a ssh1 pty");
+  if (packet_send(session) != SSH_OK) {
+    return -1;
+  }
+  if (packet_read(session) != SSH_OK) {
+    return -1;
+  }
+  if (packet_translate(session) != SSH_OK) {
+    return -1;
+  }
+
+  switch (session->in_packet.type) {
+    case SSH_SMSG_SUCCESS:
+      ssh_log(session, SSH_LOG_RARE, "PTY: Success");
+      return 0;
+      break;
+    case SSH_SMSG_FAILURE:
+      ssh_set_error(session, SSH_REQUEST_DENIED,
+          "Server denied PTY allocation");
+      ssh_log(session, SSH_LOG_RARE, "PTY: denied\n");
+      break;
+    default:
+      ssh_log(session, SSH_LOG_RARE, "PTY: error\n");
+      ssh_set_error(session, SSH_FATAL,
+          "Received unexpected packet type %d",
+          session->in_packet.type);
+      return -1;
+  }
+
+  return -1;
 }
 
-int channel_request_shell1(CHANNEL *channel){
-    SSH_SESSION *session=channel->session;
-    buffer_add_u8(session->out_buffer,SSH_CMSG_EXEC_SHELL);
-    if(packet_send(session))
-        return -1;
-    ssh_log(session, SSH_LOG_RARE, "Launched a shell");
-    return 0;
+int channel_change_pty_size1(CHANNEL *channel, int cols, int rows) {
+  SSH_SESSION *session=channel->session;
+
+  if (buffer_add_u8(session->out_buffer, SSH_CMSG_WINDOW_SIZE) < 0) {
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, ntohl(rows)) < 0) {
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, ntohl(cols)) < 0) {
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, 0) < 0) {
+    return -1;
+  }
+  if (buffer_add_u32(session->out_buffer, 0) < 0) {
+    return -1;
+  }
+
+  if (packet_send(session)) {
+    return -1;
+  }
+
+  ssh_log(session, SSH_LOG_RARE, "Change pty size send");
+
+  if (packet_wait(session, SSH_SMSG_SUCCESS, 1) < 0) {
+    return -1;
+  }
+
+  switch (session->in_packet.type) {
+    case SSH_SMSG_SUCCESS:
+      ssh_log(session, SSH_LOG_RARE, "pty size changed");
+      return 0;
+    case SSH_SMSG_FAILURE:
+      ssh_log(session, SSH_LOG_RARE, "pty size change denied");
+      ssh_set_error(session, SSH_REQUEST_DENIED, "pty size change denied");
+      return -1;
+  }
+
+  ssh_set_error(session, SSH_FATAL, "Received unexpected packet type %d",
+      session->in_packet.type);
+
+  return -1;
 }
 
-int channel_request_exec1(CHANNEL *channel, char *cmd){
-    SSH_SESSION *session=channel->session;
-    STRING *command=string_from_char(cmd);
-    buffer_add_u8(session->out_buffer,SSH_CMSG_EXEC_CMD);
-    buffer_add_ssh_string(session->out_buffer,command);
-    free(command);
-    if(packet_send(session))
-        return -1;
-    ssh_log(session, SSH_LOG_RARE, "Executing %s ...",cmd);
-    return 0;
+int channel_request_shell1(CHANNEL *channel) {
+  SSH_SESSION *session = channel->session;
+
+  if (buffer_add_u8(session->out_buffer,SSH_CMSG_EXEC_SHELL) < 0) {
+    return -1;
+  }
+
+  if (packet_send(session) != SSH_OK) {
+    return -1;
+  }
+
+  ssh_log(session, SSH_LOG_RARE, "Launched a shell");
+
+  return 0;
 }
 
-static void channel_rcv_data1(SSH_SESSION *session, int is_stderr){
-    CHANNEL *channel;
-    STRING *str;
-    channel=session->channels; // Easy. hack this when multiple channel
-                               // are comming
-    str=buffer_get_ssh_string(session->in_buffer);
-    if(!str){
-        ssh_log(session, SSH_LOG_FUNCTIONS, "Invalid data packet !\n");
-        return;
+int channel_request_exec1(CHANNEL *channel, const char *cmd) {
+  SSH_SESSION *session = channel->session;
+  STRING *command = NULL;
+
+  command = string_from_char(cmd);
+  if (command == NULL) {
+    return -1;
+  }
+
+  if (buffer_add_u8(session->out_buffer, SSH_CMSG_EXEC_CMD) < 0) {
+    string_free(command);
+    return -1;
+  }
+  if (buffer_add_ssh_string(session->out_buffer, command) < 0) {
+    string_free(command);
+    return -1;
+  }
+  string_free(command);
+
+  if(packet_send(session) != SSH_OK) {
+    return -1;
+  }
+
+  ssh_log(session, SSH_LOG_RARE, "Executing %s ...", cmd);
+
+  return 0;
+}
+
+static int channel_rcv_data1(SSH_SESSION *session, int is_stderr) {
+    CHANNEL *channel = session->channels;
+    STRING *str = NULL;
+
+    str = buffer_get_ssh_string(session->in_buffer);
+    if (str == NULL) {
+      ssh_log(session, SSH_LOG_FUNCTIONS, "Invalid data packet !\n");
+      return -1;
     }
+
     ssh_log(session, SSH_LOG_RARE,
-        "Adding %zd bytes data in %d", string_len(str), is_stderr);
-    channel_default_bufferize(channel,str->string,string_len(str),
-                    is_stderr);
-    free(str);
-}
-
-static void channel_rcv_close1(SSH_SESSION *session){
-    CHANNEL *channel=session->channels;
-    u32 status;
-    buffer_get_u32(session->in_buffer,&status);
-    /* it's much more than a channel closing. spec says it's the last
-     * message sent by server (strange)
-     */
-    /* actually status is lost somewhere */
-    channel->open=0;
-    channel->remote_eof=1;
-    buffer_add_u8(session->out_buffer,SSH_CMSG_EXIT_CONFIRMATION);
-    packet_send(session);
-}
-
-void channel_handle1(SSH_SESSION *session, int type){
-    ssh_log(session, SSH_LOG_RARE, "Channel_handle1(%d)", type);
-    switch (type){
-        case SSH_SMSG_STDOUT_DATA:
-            channel_rcv_data1(session,0);
-            break;
-        case SSH_SMSG_EXITSTATUS:
-            channel_rcv_close1(session);
-            break;
-        default:
-            ssh_log(session, SSH_LOG_FUNCTIONS, "Unexepected message %d", type);
+        "Adding %zu bytes data in %d",
+        string_len(str), is_stderr);
 
+    if (channel_default_bufferize(channel, str->string, string_len(str),
+          is_stderr) < 0) {
+      string_free(str);
+      return -1;
     }
+    string_free(str);
+
+    return 0;
 }
 
-int channel_write1(CHANNEL *channel, void *data, int len){
-    SSH_SESSION *session=channel->session;
-    int origlen=len;
-    int effectivelen;
-    while(len>0){
-        buffer_add_u8(session->out_buffer,SSH_CMSG_STDIN_DATA);
-        if(len > 32000)
-            effectivelen=32000;
-        else
-            effectivelen=len;
-        buffer_add_u32(session->out_buffer,htonl(effectivelen));
-        buffer_add_data(session->out_buffer,data,effectivelen);
-        data+=effectivelen;
-        len-=effectivelen;
-        if(packet_send(session))
-            return -1;
+static int channel_rcv_close1(SSH_SESSION *session) {
+  CHANNEL *channel = session->channels;
+  u32 status;
+
+  buffer_get_u32(session->in_buffer, &status);
+  /*
+   * It's much more than a channel closing. spec says it's the last
+   * message sent by server (strange)
+   */
+
+  /* actually status is lost somewhere */
+  channel->open = 0;
+  channel->remote_eof = 1;
+
+  if (buffer_add_u8(session->out_buffer, SSH_CMSG_EXIT_CONFIRMATION) < 0) {
+    return -1;
+  }
+
+  if (packet_send(session) != SSH_OK) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int channel_handle1(SSH_SESSION *session, int type) {
+  ssh_log(session, SSH_LOG_RARE, "Channel_handle1(%d)", type);
+  switch (type) {
+    case SSH_SMSG_STDOUT_DATA:
+      if (channel_rcv_data1(session,0) < 0) {
+        return -1;
+      }
+      break;
+    case SSH_SMSG_EXITSTATUS:
+      channel_rcv_close1(session);
+      break;
+    default:
+      ssh_log(session, SSH_LOG_FUNCTIONS, "Unexepected message %d", type);
+  }
+
+  return 0;
+}
+
+int channel_write1(CHANNEL *channel, void *data, int len) {
+  SSH_SESSION *session = channel->session;
+  int origlen = len;
+  int effectivelen;
+
+  while (len > 0) {
+    if (buffer_add_u8(session->out_buffer, SSH_CMSG_STDIN_DATA) < 0) {
+      return -1;
     }
-    return origlen;
+
+    effectivelen = len > 32000 ? 32000 : len;
+
+    if (buffer_add_u32(session->out_buffer, htonl(effectivelen)) < 0) {
+      return -1;
+    }
+    if (buffer_add_data(session->out_buffer, data, effectivelen) < 0) {
+      return -1;
+    }
+
+    data += effectivelen;
+    len -= effectivelen;
+
+    if (packet_send(session) != SSH_OK) {
+      return -1;
+    }
+  }
+
+  return origlen;
 }
 
 #endif /* HAVE_SSH1 */