/*
 * Memory management routine
 * Copyright (C) 1998 Kunihiro Ishiguro
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2, or (at your option) any
 * later version.
 *
 * GNU Zebra 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 GNU Zebra; see the file COPYING.  If not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.  
 */

#include <zebra.h>
/* malloc.h is generally obsolete, however GNU Libc mallinfo wants it. */
#if !defined(HAVE_STDLIB_H) || (defined(GNU_LINUX) && defined(HAVE_MALLINFO))
#include <malloc.h>
#endif /* !HAVE_STDLIB_H || HAVE_MALLINFO */

#include "log.h"
#include "memory.h"

static void alloc_inc (int);
static void alloc_dec (int);
static void log_memstats(int log_priority);

static const struct message mstr [] =
{
  { MTYPE_THREAD, "thread" },
  { MTYPE_THREAD_MASTER, "thread_master" },
  { MTYPE_VECTOR, "vector" },
  { MTYPE_VECTOR_INDEX, "vector_index" },
  { MTYPE_IF, "interface" },
  { 0, NULL },
};

/* Fatal memory allocation error occured. */
static void __attribute__ ((noreturn))
zerror (const char *fname, int type, size_t size)
{
  zlog_err ("%s : can't allocate memory for `%s' size %d: %s\n", 
	    fname, lookup (mstr, type), (int) size, safe_strerror(errno));
  log_memstats(LOG_WARNING);
  /* N.B. It might be preferable to call zlog_backtrace_sigsafe here, since
     that function should definitely be safe in an OOM condition.  But
     unfortunately zlog_backtrace_sigsafe does not support syslog logging at
     this time... */
  zlog_backtrace(LOG_WARNING);
  abort();
}

/*
 * Allocate memory of a given size, to be tracked by a given type.
 * Effects: Returns a pointer to usable memory.  If memory cannot
 * be allocated, aborts execution.
 */
void *
zmalloc (int type, size_t size)
{
  void *memory;

  memory = malloc (size);

  if (memory == NULL)
    zerror ("malloc", type, size);

  alloc_inc (type);

  return memory;
}

/*
 * Allocate memory as in zmalloc, and also clear the memory.
 * Add an extra 'z' prefix to function name to avoid collision when linking
 * statically with zlib that exports the 'zcalloc' symbol.
 */
void *
zzcalloc (int type, size_t size)
{
  void *memory;

  memory = calloc (1, size);

  if (memory == NULL)
    zerror ("calloc", type, size);

  alloc_inc (type);

  return memory;
}

/* 
 * Given a pointer returned by zmalloc or zzcalloc, free it and
 * return a pointer to a new size, basically acting like realloc().
 * Requires: ptr was returned by zmalloc, zzcalloc, or zrealloc with the
 * same type.
 * Effects: Returns a pointer to the new memory, or aborts.
 */
void *
zrealloc (int type, void *ptr, size_t size)
{
  void *memory;

  if (ptr == NULL)              /* is really alloc */
      return zzcalloc(type, size);

  memory = realloc (ptr, size);
  if (memory == NULL)
    zerror ("realloc", type, size);
  if (ptr == NULL)
    alloc_inc (type);

  return memory;
}

/*
 * Free memory allocated by z*alloc or zstrdup.
 * Requires: ptr was returned by zmalloc, zzcalloc, or zrealloc with the
 * same type.
 * Effects: The memory is freed and may no longer be referenced.
 */
void
zfree (int type, void *ptr)
{
  if (ptr != NULL)
    {
      alloc_dec (type);
      free (ptr);
    }
}

/*
 * Duplicate a string, counting memory usage by type.
 * Effects: The string is duplicated, and the return value must
 * eventually be passed to zfree with the same type.  The function will
 * succeed or abort.
 */
char *
zstrdup (int type, const char *str)
{
  void *dup;

  dup = strdup (str);
  if (dup == NULL)
    zerror ("strdup", type, strlen (str));
  alloc_inc (type);
  return dup;
}

#ifdef MEMORY_LOG
static struct 
{
  const char *name;
  long alloc;
  unsigned long t_malloc;
  unsigned long c_malloc;
  unsigned long t_calloc;
  unsigned long c_calloc;
  unsigned long t_realloc;
  unsigned long t_free;
  unsigned long c_strdup;
} mstat [MTYPE_MAX];

static void
mtype_log (char *func, void *memory, const char *file, int line, int type)
{
  zlog_debug ("%s: %s %p %s %d", func, lookup (mstr, type), memory, file, line);
}

void *
mtype_zmalloc (const char *file, int line, int type, size_t size)
{
  void *memory;

  mstat[type].c_malloc++;
  mstat[type].t_malloc++;

  memory = zmalloc (type, size);
  mtype_log ("zmalloc", memory, file, line, type);

  return memory;
}

void *
mtype_zcalloc (const char *file, int line, int type, size_t size)
{
  void *memory;

  mstat[type].c_calloc++;
  mstat[type].t_calloc++;

  memory = zzcalloc (type, size);
  mtype_log ("xcalloc", memory, file, line, type);

  return memory;
}

void *
mtype_zrealloc (const char *file, int line, int type, void *ptr, size_t size)
{
  void *memory;

  /* Realloc need before allocated pointer. */
  mstat[type].t_realloc++;

  memory = zrealloc (type, ptr, size);

  mtype_log ("xrealloc", memory, file, line, type);

  return memory;
}

/* Important function. */
void 
mtype_zfree (const char *file, int line, int type, void *ptr)
{
  mstat[type].t_free++;

  mtype_log ("xfree", ptr, file, line, type);

  zfree (type, ptr);
}

char *
mtype_zstrdup (const char *file, int line, int type, const char *str)
{
  char *memory;

  mstat[type].c_strdup++;

  memory = zstrdup (type, str);
  
  mtype_log ("xstrdup", memory, file, line, type);

  return memory;
}
#else
static struct 
{
  char *name;
  long alloc;
} mstat [MTYPE_MAX];
#endif /* MEMORY_LOG */

/* Increment allocation counter. */
static void
alloc_inc (int type)
{
  mstat[type].alloc++;
}

/* Decrement allocation counter. */
static void
alloc_dec (int type)
{
  mstat[type].alloc--;
}

/* Looking up memory status from vty interface. */
#include "vector.h"
#include "vty.h"
#include "command.h"

static void
log_memstats(int pri)
{
  struct mlist *ml;

  for (ml = mlists; ml->list; ml++)
    {
      struct memory_list *m;

      zlog (NULL, pri, "Memory utilization in module %s:", ml->name);
      for (m = ml->list; m->index >= 0; m++)
	if (m->index && mstat[m->index].alloc)
	  zlog (NULL, pri, "  %-30s: %10ld", m->format, mstat[m->index].alloc);
    }
}

void
log_memstats_stderr (const char *prefix)
{
  struct mlist *ml;
  struct memory_list *m;
  int i;
  int j = 0;

  for (ml = mlists; ml->list; ml++)
    {
      i = 0;

      for (m = ml->list; m->index >= 0; m++)
        if (m->index && mstat[m->index].alloc)
          {
            if (!i)
              fprintf (stderr,
                       "%s: memstats: Current memory utilization in module %s:\n",
                       prefix,
                       ml->name);
            fprintf (stderr,
                     "%s: memstats:  %-30s: %10ld%s\n",
                     prefix,
                     m->format,
                     mstat[m->index].alloc,
                     mstat[m->index].alloc < 0 ? " (REPORT THIS BUG!)" : "");
            i = j = 1;
          }
    }

  if (j)
    fprintf (stderr,
             "%s: memstats: NOTE: If configuration exists, utilization may be "
             "expected.\n",
             prefix);
  else
    fprintf (stderr,
             "%s: memstats: No remaining tracked memory utilization.\n",
             prefix);
}

static void
show_separator(struct vty *vty)
{
  vty_out (vty, "-----------------------------\r\n");
}

static int
show_memory_vty (struct vty *vty, struct memory_list *list)
{
  struct memory_list *m;
  int needsep = 0;

  for (m = list; m->index >= 0; m++)
    if (m->index == 0)
      {
	if (needsep)
	  {
	    show_separator (vty);
	    needsep = 0;
	  }
      }
    else if (mstat[m->index].alloc)
      {
	vty_out (vty, "%-30s: %10ld\r\n", m->format, mstat[m->index].alloc);
	needsep = 1;
      }
  return needsep;
}

#ifdef HAVE_MALLINFO
static int
show_memory_mallinfo (struct vty *vty)
{
  struct mallinfo minfo = mallinfo();
  char buf[MTYPE_MEMSTR_LEN];
  
  vty_out (vty, "System allocator statistics:%s", VTY_NEWLINE);
  vty_out (vty, "  Total heap allocated:  %s%s",
           mtype_memstr (buf, MTYPE_MEMSTR_LEN, minfo.arena),
           VTY_NEWLINE);
  vty_out (vty, "  Holding block headers: %s%s",
           mtype_memstr (buf, MTYPE_MEMSTR_LEN, minfo.hblkhd),
           VTY_NEWLINE);
  vty_out (vty, "  Used small blocks:     %s%s",
           mtype_memstr (buf, MTYPE_MEMSTR_LEN, minfo.usmblks),
           VTY_NEWLINE);
  vty_out (vty, "  Used ordinary blocks:  %s%s",
           mtype_memstr (buf, MTYPE_MEMSTR_LEN, minfo.uordblks),
           VTY_NEWLINE);
  vty_out (vty, "  Free small blocks:     %s%s",
           mtype_memstr (buf, MTYPE_MEMSTR_LEN, minfo.fsmblks),
           VTY_NEWLINE);
  vty_out (vty, "  Free ordinary blocks:  %s%s",
           mtype_memstr (buf, MTYPE_MEMSTR_LEN, minfo.fordblks),
           VTY_NEWLINE);
  vty_out (vty, "  Ordinary blocks:       %ld%s",
           (unsigned long)minfo.ordblks,
           VTY_NEWLINE);
  vty_out (vty, "  Small blocks:          %ld%s",
           (unsigned long)minfo.smblks,
           VTY_NEWLINE);
  vty_out (vty, "  Holding blocks:        %ld%s",
           (unsigned long)minfo.hblks,
           VTY_NEWLINE);
  vty_out (vty, "(see system documentation for 'mallinfo' for meaning)%s",
           VTY_NEWLINE);
  return 1;
}
#endif /* HAVE_MALLINFO */

DEFUN (show_memory,
       show_memory_cmd,
       "show memory",
       "Show running system information\n"
       "Memory statistics\n")
{
  struct mlist *ml;
  int needsep = 0;
  
#ifdef HAVE_MALLINFO
  needsep = show_memory_mallinfo (vty);
#endif /* HAVE_MALLINFO */
  
  for (ml = mlists; ml->list; ml++)
    {
      if (needsep)
	show_separator (vty);
      needsep = show_memory_vty (vty, ml->list);
    }

  return CMD_SUCCESS;
}


void
memory_init (void)
{
  install_element (RESTRICTED_NODE, &show_memory_cmd);

  install_element (VIEW_NODE, &show_memory_cmd);
}

/* Stats querying from users */
/* Return a pointer to a human friendly string describing
 * the byte count passed in. E.g:
 * "0 bytes", "2048 bytes", "110kB", "500MiB", "11GiB", etc.
 * Up to 4 significant figures will be given.
 * The pointer returned may be NULL (indicating an error)
 * or point to the given buffer, or point to static storage.
 */
const char *
mtype_memstr (char *buf, size_t len, unsigned long bytes)
{
  unsigned int m, k;

  /* easy cases */
  if (!bytes)
    return "0 bytes";
  if (bytes == 1)
    return "1 byte";

  /*
   * When we pass the 2gb barrier mallinfo() can no longer report
   * correct data so it just does something odd...
   * Reporting like Terrabytes of data.  Which makes users...
   * edgy.. yes edgy that's the term for it.
   * So let's just give up gracefully
   */
  if (bytes > 0x7fffffff)
    return "> 2GB";

  m = bytes >> 20;
  k = bytes >> 10;

 if (m > 10)
    {
      if (bytes & (1 << 19))
        m++;
      snprintf (buf, len, "%d MiB", m);
    }
  else if (k > 10)
    {
      if (bytes & (1 << 9))
        k++;
      snprintf (buf, len, "%d KiB", k);
    }
  else
    snprintf (buf, len, "%ld bytes", bytes);
  
  return buf;
}

unsigned long
mtype_stats_alloc (int type)
{
  return mstat[type].alloc;
}