/* Copyright (C) 2010-2014 B.A.T.M.A.N. contributors:

   *
   * Marek Lindner
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of version 2 of the GNU General Public
   * License as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License

   * along with this program; if not, see <http://www.gnu.org/licenses/>.

   */
  
  #include "main.h"
  
  #include <linux/debugfs.h>

  #include "debugfs.h"

  #include "translation-table.h"
  #include "originator.h"
  #include "hard-interface.h"
  #include "gateway_common.h"
  #include "gateway_client.h"
  #include "soft-interface.h"

  #include "icmp_socket.h"

  #include "bridge_loop_avoidance.h"

  #include "distributed-arp-table.h"

  #include "network-coding.h"

  static struct dentry *batadv_debugfs;

  
  #ifdef CONFIG_BATMAN_ADV_DEBUG

  #define BATADV_LOG_BUFF_MASK (batadv_log_buff_len - 1)

  static const int batadv_log_buff_len = BATADV_LOG_BUF_LEN;

  static char *batadv_log_char_addr(struct batadv_priv_debug_log *debug_log,

  				  size_t idx)
  {
  	return &debug_log->log_buff[idx & BATADV_LOG_BUFF_MASK];
  }

  static void batadv_emit_log_char(struct batadv_priv_debug_log *debug_log,
  				 char c)

  {

  	char *char_addr;
  
  	char_addr = batadv_log_char_addr(debug_log, debug_log->log_end);
  	*char_addr = c;

  	debug_log->log_end++;

  	if (debug_log->log_end - debug_log->log_start > batadv_log_buff_len)
  		debug_log->log_start = debug_log->log_end - batadv_log_buff_len;

  }

  __printf(2, 3)

  static int batadv_fdebug_log(struct batadv_priv_debug_log *debug_log,

  			     const char *fmt, ...)

  {

  	va_list args;
  	static char debug_log_buf[256];
  	char *p;
  
  	if (!debug_log)
  		return 0;
  
  	spin_lock_bh(&debug_log->lock);
  	va_start(args, fmt);

  	vscnprintf(debug_log_buf, sizeof(debug_log_buf), fmt, args);

  	va_end(args);
  
  	for (p = debug_log_buf; *p != 0; p++)

  		batadv_emit_log_char(debug_log, *p);

  
  	spin_unlock_bh(&debug_log->lock);
  
  	wake_up(&debug_log->queue_wait);
  
  	return 0;
  }

  int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)

  {
  	va_list args;
  	char tmp_log_buf[256];
  
  	va_start(args, fmt);
  	vscnprintf(tmp_log_buf, sizeof(tmp_log_buf), fmt, args);

  	batadv_fdebug_log(bat_priv->debug_log, "[%10u] %s",
  			  jiffies_to_msecs(jiffies), tmp_log_buf);

  	va_end(args);
  
  	return 0;
  }

  static int batadv_log_open(struct inode *inode, struct file *file)

  {

  	if (!try_module_get(THIS_MODULE))
  		return -EBUSY;

  	nonseekable_open(inode, file);
  	file->private_data = inode->i_private;

  	return 0;
  }

  static int batadv_log_release(struct inode *inode, struct file *file)

  {

  	module_put(THIS_MODULE);

  	return 0;
  }

  static int batadv_log_empty(struct batadv_priv_debug_log *debug_log)

  {
  	return !(debug_log->log_start - debug_log->log_end);
  }

  static ssize_t batadv_log_read(struct file *file, char __user *buf,
  			       size_t count, loff_t *ppos)

  {

  	struct batadv_priv *bat_priv = file->private_data;

  	struct batadv_priv_debug_log *debug_log = bat_priv->debug_log;

  	int error, i = 0;

  	char *char_addr;

  	char c;

  	if ((file->f_flags & O_NONBLOCK) && batadv_log_empty(debug_log))

  		return -EAGAIN;

  	if (!buf)

  		return -EINVAL;
  
  	if (count == 0)
  		return 0;
  
  	if (!access_ok(VERIFY_WRITE, buf, count))
  		return -EFAULT;
  
  	error = wait_event_interruptible(debug_log->queue_wait,

  					 (!batadv_log_empty(debug_log)));

  
  	if (error)
  		return error;
  
  	spin_lock_bh(&debug_log->lock);
  
  	while ((!error) && (i < count) &&
  	       (debug_log->log_start != debug_log->log_end)) {

  		char_addr = batadv_log_char_addr(debug_log,
  						 debug_log->log_start);
  		c = *char_addr;

  
  		debug_log->log_start++;
  
  		spin_unlock_bh(&debug_log->lock);
  
  		error = __put_user(c, buf);
  
  		spin_lock_bh(&debug_log->lock);
  
  		buf++;
  		i++;

  	}
  
  	spin_unlock_bh(&debug_log->lock);
  
  	if (!error)
  		return i;
  
  	return error;
  }

  static unsigned int batadv_log_poll(struct file *file, poll_table *wait)

  {

  	struct batadv_priv *bat_priv = file->private_data;

  	struct batadv_priv_debug_log *debug_log = bat_priv->debug_log;

  
  	poll_wait(file, &debug_log->queue_wait, wait);

  	if (!batadv_log_empty(debug_log))

  		return POLLIN | POLLRDNORM;
  
  	return 0;
  }

  static const struct file_operations batadv_log_fops = {
  	.open           = batadv_log_open,
  	.release        = batadv_log_release,
  	.read           = batadv_log_read,
  	.poll           = batadv_log_poll,

  	.llseek         = no_llseek,
  };

  static int batadv_debug_log_setup(struct batadv_priv *bat_priv)

  {
  	struct dentry *d;
  
  	if (!bat_priv->debug_dir)
  		goto err;

  	bat_priv->debug_log = kzalloc(sizeof(*bat_priv->debug_log), GFP_ATOMIC);

  	if (!bat_priv->debug_log)
  		goto err;
  
  	spin_lock_init(&bat_priv->debug_log->lock);
  	init_waitqueue_head(&bat_priv->debug_log->queue_wait);
  
  	d = debugfs_create_file("log", S_IFREG | S_IRUSR,

  				bat_priv->debug_dir, bat_priv,
  				&batadv_log_fops);

  	if (!d)

  		goto err;
  
  	return 0;
  
  err:

  	return -ENOMEM;

  }

  static void batadv_debug_log_cleanup(struct batadv_priv *bat_priv)

  {
  	kfree(bat_priv->debug_log);
  	bat_priv->debug_log = NULL;
  }
  #else /* CONFIG_BATMAN_ADV_DEBUG */

  static int batadv_debug_log_setup(struct batadv_priv *bat_priv)

  {

  	return 0;
  }

  static void batadv_debug_log_cleanup(struct batadv_priv *bat_priv)

  {
  	return;
  }
  #endif

  static int batadv_algorithms_open(struct inode *inode, struct file *file)

  {

  	return single_open(file, batadv_algo_seq_print_text, NULL);

  }

  static int batadv_originators_open(struct inode *inode, struct file *file)

  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_orig_seq_print_text, net_dev);

  }

  /**
   * batadv_originators_hardif_open - handles debugfs output for the
   *  originator table of an hard interface
   * @inode: inode pointer to debugfs file
   * @file: pointer to the seq_file
   */
  static int batadv_originators_hardif_open(struct inode *inode,
  					  struct file *file)
  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_orig_hardif_seq_print_text, net_dev);
  }

  static int batadv_gateways_open(struct inode *inode, struct file *file)

  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_gw_client_seq_print_text, net_dev);

  }

  static int batadv_transtable_global_open(struct inode *inode, struct file *file)

  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_tt_global_seq_print_text, net_dev);

  }

  #ifdef CONFIG_BATMAN_ADV_BLA

  static int batadv_bla_claim_table_open(struct inode *inode, struct file *file)

  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_bla_claim_table_seq_print_text,
  			   net_dev);

  }

  
  static int batadv_bla_backbone_table_open(struct inode *inode,
  					  struct file *file)
  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_bla_backbone_table_seq_print_text,
  			   net_dev);
  }

  #endif

  #ifdef CONFIG_BATMAN_ADV_DAT

  /**
   * batadv_dat_cache_open - Prepare file handler for reads from dat_chache
   * @inode: inode which was opened
   * @file: file handle to be initialized
   */
  static int batadv_dat_cache_open(struct inode *inode, struct file *file)
  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_dat_cache_seq_print_text, net_dev);
  }

  #endif

  static int batadv_transtable_local_open(struct inode *inode, struct file *file)

  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_tt_local_seq_print_text, net_dev);

  }

  struct batadv_debuginfo {

  	struct attribute attr;
  	const struct file_operations fops;
  };

  #ifdef CONFIG_BATMAN_ADV_NC
  static int batadv_nc_nodes_open(struct inode *inode, struct file *file)
  {
  	struct net_device *net_dev = (struct net_device *)inode->i_private;

  	return single_open(file, batadv_nc_nodes_seq_print_text, net_dev);
  }
  #endif

  #define BATADV_DEBUGINFO(_name, _mode, _open)		\

  struct batadv_debuginfo batadv_debuginfo_##_name = {	\

  	.attr = { .name = __stringify(_name),		\
  		  .mode = _mode, },			\
  	.fops = { .owner = THIS_MODULE,			\
  		  .open = _open,			\
  		  .read	= seq_read,			\
  		  .llseek = seq_lseek,			\
  		  .release = single_release,		\
  		}					\

  }

  /* the following attributes are general and therefore they will be directly
   * placed in the BATADV_DEBUGFS_SUBDIR subdirectory of debugfs
   */

  static BATADV_DEBUGINFO(routing_algos, S_IRUGO, batadv_algorithms_open);

  
  static struct batadv_debuginfo *batadv_general_debuginfos[] = {
  	&batadv_debuginfo_routing_algos,
  	NULL,
  };
  
  /* The following attributes are per soft interface */

  static BATADV_DEBUGINFO(originators, S_IRUGO, batadv_originators_open);
  static BATADV_DEBUGINFO(gateways, S_IRUGO, batadv_gateways_open);
  static BATADV_DEBUGINFO(transtable_global, S_IRUGO,
  			batadv_transtable_global_open);

  #ifdef CONFIG_BATMAN_ADV_BLA

  static BATADV_DEBUGINFO(bla_claim_table, S_IRUGO, batadv_bla_claim_table_open);

  static BATADV_DEBUGINFO(bla_backbone_table, S_IRUGO,
  			batadv_bla_backbone_table_open);

  #endif

  #ifdef CONFIG_BATMAN_ADV_DAT

  static BATADV_DEBUGINFO(dat_cache, S_IRUGO, batadv_dat_cache_open);

  #endif

  static BATADV_DEBUGINFO(transtable_local, S_IRUGO,
  			batadv_transtable_local_open);

  #ifdef CONFIG_BATMAN_ADV_NC
  static BATADV_DEBUGINFO(nc_nodes, S_IRUGO, batadv_nc_nodes_open);
  #endif

  static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {

  	&batadv_debuginfo_originators,
  	&batadv_debuginfo_gateways,
  	&batadv_debuginfo_transtable_global,

  #ifdef CONFIG_BATMAN_ADV_BLA

  	&batadv_debuginfo_bla_claim_table,

  	&batadv_debuginfo_bla_backbone_table,

  #endif

  #ifdef CONFIG_BATMAN_ADV_DAT

  	&batadv_debuginfo_dat_cache,

  #endif

  	&batadv_debuginfo_transtable_local,

  #ifdef CONFIG_BATMAN_ADV_NC
  	&batadv_debuginfo_nc_nodes,
  #endif

  	NULL,
  };

  #define BATADV_HARDIF_DEBUGINFO(_name, _mode, _open)		\
  struct batadv_debuginfo batadv_hardif_debuginfo_##_name = {	\
  	.attr = {						\
  		.name = __stringify(_name),			\
  		.mode = _mode,					\
  	},							\
  	.fops = {						\
  		.owner = THIS_MODULE,				\
  		.open = _open,					\
  		.read	= seq_read,				\
  		.llseek = seq_lseek,				\
  		.release = single_release,			\
  	},							\

  }

  static BATADV_HARDIF_DEBUGINFO(originators, S_IRUGO,
  			       batadv_originators_hardif_open);

  
  static struct batadv_debuginfo *batadv_hardif_debuginfos[] = {

  	&batadv_hardif_debuginfo_originators,

  	NULL,
  };

  void batadv_debugfs_init(void)

  {

  	struct batadv_debuginfo **bat_debug;

  	struct dentry *file;

  	batadv_debugfs = debugfs_create_dir(BATADV_DEBUGFS_SUBDIR, NULL);

  	if (batadv_debugfs == ERR_PTR(-ENODEV))
  		batadv_debugfs = NULL;

  	if (!batadv_debugfs)

  		goto err;

  	for (bat_debug = batadv_general_debuginfos; *bat_debug; ++bat_debug) {
  		file = debugfs_create_file(((*bat_debug)->attr).name,
  					   S_IFREG | ((*bat_debug)->attr).mode,
  					   batadv_debugfs, NULL,
  					   &(*bat_debug)->fops);
  		if (!file) {
  			pr_err("Can't add general debugfs file: %s
  ",
  			       ((*bat_debug)->attr).name);
  			goto err;
  		}
  	}

  	return;

  err:
  	debugfs_remove_recursive(batadv_debugfs);

  	batadv_debugfs = NULL;

  }

  void batadv_debugfs_destroy(void)

  {

  	debugfs_remove_recursive(batadv_debugfs);
  	batadv_debugfs = NULL;

  }

  /**
   * batadv_debugfs_add_hardif - creates the base directory for a hard interface
   *  in debugfs.
   * @hard_iface: hard interface which should be added.
   */
  int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface)
  {
  	struct batadv_debuginfo **bat_debug;
  	struct dentry *file;
  
  	if (!batadv_debugfs)
  		goto out;
  
  	hard_iface->debug_dir = debugfs_create_dir(hard_iface->net_dev->name,
  						   batadv_debugfs);
  	if (!hard_iface->debug_dir)
  		goto out;
  
  	for (bat_debug = batadv_hardif_debuginfos; *bat_debug; ++bat_debug) {
  		file = debugfs_create_file(((*bat_debug)->attr).name,
  					   S_IFREG | ((*bat_debug)->attr).mode,
  					   hard_iface->debug_dir,
  					   hard_iface->net_dev,
  					   &(*bat_debug)->fops);
  		if (!file)
  			goto rem_attr;
  	}
  
  	return 0;
  rem_attr:
  	debugfs_remove_recursive(hard_iface->debug_dir);
  	hard_iface->debug_dir = NULL;
  out:
  #ifdef CONFIG_DEBUG_FS
  	return -ENOMEM;
  #else
  	return 0;
  #endif /* CONFIG_DEBUG_FS */
  }
  
  /**
   * batadv_debugfs_del_hardif - delete the base directory for a hard interface
   *  in debugfs.
   * @hard_iface: hard interface which is deleted.
   */
  void batadv_debugfs_del_hardif(struct batadv_hard_iface *hard_iface)
  {
  	if (batadv_debugfs) {
  		debugfs_remove_recursive(hard_iface->debug_dir);
  		hard_iface->debug_dir = NULL;
  	}
  }

  int batadv_debugfs_add_meshif(struct net_device *dev)

  {

  	struct batadv_priv *bat_priv = netdev_priv(dev);

  	struct batadv_debuginfo **bat_debug;

  	struct dentry *file;

  	if (!batadv_debugfs)

  		goto out;

  	bat_priv->debug_dir = debugfs_create_dir(dev->name, batadv_debugfs);

  	if (!bat_priv->debug_dir)
  		goto out;

  	if (batadv_socket_setup(bat_priv) < 0)

  		goto rem_attr;

  	if (batadv_debug_log_setup(bat_priv) < 0)

  		goto rem_attr;

  	for (bat_debug = batadv_mesh_debuginfos; *bat_debug; ++bat_debug) {

  		file = debugfs_create_file(((*bat_debug)->attr).name,

  					   S_IFREG | ((*bat_debug)->attr).mode,
  					   bat_priv->debug_dir,
  					   dev, &(*bat_debug)->fops);

  		if (!file) {

  			batadv_err(dev, "Can't add debugfs file: %s/%s
  ",
  				   dev->name, ((*bat_debug)->attr).name);

  			goto rem_attr;
  		}
  	}

  	if (batadv_nc_init_debugfs(bat_priv) < 0)
  		goto rem_attr;

  	return 0;
  rem_attr:
  	debugfs_remove_recursive(bat_priv->debug_dir);
  	bat_priv->debug_dir = NULL;
  out:
  #ifdef CONFIG_DEBUG_FS
  	return -ENOMEM;
  #else
  	return 0;
  #endif /* CONFIG_DEBUG_FS */
  }

  void batadv_debugfs_del_meshif(struct net_device *dev)

  {

  	struct batadv_priv *bat_priv = netdev_priv(dev);

  	batadv_debug_log_cleanup(bat_priv);

  	if (batadv_debugfs) {

  		debugfs_remove_recursive(bat_priv->debug_dir);
  		bat_priv->debug_dir = NULL;
  	}
  }