/*
   (c) Copyright 2001-2009  The world wide DirectFB Open Source Community (directfb.org)
   (c) Copyright 2000-2004  Convergence (integrated media) GmbH

   All rights reserved.

   Written by Denis Oliver Kropp <dok@directfb.org>,
              Andreas Hundt <andi@fischlustig.de>,
              Sven Neumann <neo@directfb.org>,
              Ville Syrjälä <syrjala@sci.fi> and
              Claudio Ciccani <klan@users.sf.net>.

   This 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 the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   This library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, write to the
   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.
*/

#include <config.h>

#include <direct/build.h>


#if DIRECT_BUILD_DEBUGS  /* Build with debug support? */

#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <sys/types.h>
#include <signal.h>

#include <direct/debug.h>
#include <direct/mem.h>
#include <direct/memcpy.h>
#include <direct/messages.h>
#include <direct/trace.h>
#include <direct/util.h>


D_DEBUG_DOMAIN( Direct_Mem, "Direct/Mem", "libdirect memory allocation (debugging)" );

/**********************************************************************************************************************/

typedef struct {
     const void        *mem;
     size_t             bytes;
     const char        *func;
     const char        *file;
     int                line;
     DirectTraceBuffer *trace;
} MemDesc;

/**********************************************************************************************************************/

static int              alloc_count    = 0;
static int              alloc_capacity = 0;
static MemDesc         *alloc_list     = NULL;
static pthread_mutex_t  alloc_lock     = PTHREAD_MUTEX_INITIALIZER;

/**********************************************************************************************************************/

void
direct_print_memleaks( void )
{
     unsigned int i;

     /* Debug only. */
     pthread_mutex_lock( &alloc_lock );

     if (alloc_count && (!direct_config || direct_config->debugmem)) {
          direct_log_printf( NULL, "Local memory allocations remaining (%d): \n", alloc_count );

          for (i=0; i<alloc_count; i++) {
               MemDesc *desc = &alloc_list[i];

               direct_log_printf( NULL, "%7zu bytes at %p allocated in %s (%s: %u)\n",
                                  desc->bytes, desc->mem, desc->func, desc->file, desc->line );

               if (desc->trace)
                    direct_trace_print_stack( desc->trace );
          }
     }

     pthread_mutex_unlock( &alloc_lock );
}

/**********************************************************************************************************************/

/* FIXME: Replace array by linked list, or at least avoid the memmove on free of an item. */

static MemDesc *
allocate_mem_desc( void )
{
     int cap = alloc_capacity;

     if (!cap)
          cap = 64;
     else if (cap == alloc_count)
          cap <<= 1;

     if (cap != alloc_capacity) {
          void *new_list = malloc( sizeof(MemDesc) * cap );

          if (!new_list) {
               D_WARN( "could not allocate more descriptors (%d->%d)", alloc_capacity, cap );
               return NULL;
          }

          direct_memcpy( new_list, alloc_list, sizeof(MemDesc) * alloc_count );

          free( alloc_list );

          alloc_capacity = cap;
          alloc_list     = new_list;
     }

     return &alloc_list[alloc_count++];
}

static inline void
fill_mem_desc( MemDesc *desc, const void *mem, int bytes,
               const char *func, const char *file, int line, DirectTraceBuffer *trace )
{
     desc->mem   = mem;
     desc->bytes = bytes;
     desc->func  = func;
     desc->file  = file;
     desc->line  = line;
     desc->trace = trace;
}

/**********************************************************************************************************************/

void *
direct_malloc( const char* file, int line, const char *func, size_t bytes )
{
     void    *mem;
     MemDesc *desc;

     D_DEBUG_AT( Direct_Mem, "  +%6zu bytes [%s:%d in %s()]\n", bytes, file, line, func );

     mem = malloc( bytes );
     if (!mem)
          return NULL;

     if (!direct_config->debugmem)
          return mem;


     /* Debug only. */
     pthread_mutex_lock( &alloc_lock );
     desc = allocate_mem_desc();
     pthread_mutex_unlock( &alloc_lock );

     if (desc)
          fill_mem_desc( desc, mem, bytes, func, file, line, direct_trace_copy_buffer(NULL) );

     return mem;
}

void *
direct_calloc( const char* file, int line, const char *func, size_t count, size_t bytes )
{
     void    *mem;
     MemDesc *desc;

     D_DEBUG_AT( Direct_Mem, "  +%6zu bytes [%s:%d in %s()]\n", count * bytes, file, line, func );

     mem = calloc( count, bytes );
     if (!mem)
          return NULL;

     if (!direct_config->debugmem)
          return mem;


     /* Debug only. */
     pthread_mutex_lock( &alloc_lock );
     desc = allocate_mem_desc();
     pthread_mutex_unlock( &alloc_lock );

     if (desc)
          fill_mem_desc( desc, mem, count * bytes, func, file, line, direct_trace_copy_buffer(NULL) );

     return mem;
}

void *
direct_realloc( const char *file, int line, const char *func, const char *what, void *mem, size_t bytes )
{
     int i;

     if (!mem)
          return direct_malloc( file, line, func, bytes );

     if (!bytes) {
          direct_free( file, line, func, what, mem );
          return NULL;
     }

     if (!direct_config->debugmem) {
          D_DEBUG_AT( Direct_Mem, "  *%6zu bytes [%s:%d in %s()] '%s'\n", bytes, file, line, func, what );
          return realloc( mem, bytes );
     }


     /* Debug only. */
     pthread_mutex_lock( &alloc_lock );

     for (i=0; i<alloc_count; i++) {
          MemDesc *desc = &alloc_list[i];

          if (desc->mem == mem) {
               void *new_mem = realloc( mem, bytes );

               D_DEBUG_AT( Direct_Mem, "  %c%6zu bytes [%s:%d in %s()] (%s%zu) <- %p -> %p '%s'\n",
                           (bytes > desc->bytes) ? '>' : '<', bytes, file, line, func,
                           (bytes > desc->bytes) ? "+" : "", bytes - desc->bytes, mem, new_mem, what);

               if (desc->trace) {
                    direct_trace_free_buffer( desc->trace );
                    desc->trace = NULL;
               }

               if (!new_mem) {
                    D_WARN( "could not reallocate memory (%p: %zu->%zu)", mem, desc->bytes, bytes );

                    alloc_count--;

                    /* FIXME: This can be very slow. */
                    if (i < alloc_count)
                         direct_memmove( desc, desc + 1, (alloc_count - i) * sizeof(MemDesc) );
               }
               else
                    fill_mem_desc( desc, new_mem, bytes, func, file, line, direct_trace_copy_buffer(NULL) );

               pthread_mutex_unlock( &alloc_lock );

               return new_mem;
          }
     }

     pthread_mutex_unlock( &alloc_lock );

     D_ERROR( "Direct/Mem: Not reallocating unknown %p (%s) from [%s:%d in %s()] - corrupt/incomplete list?\n",
              mem, what, file, line, func );

     return direct_malloc( file, line, func, bytes );
}

void
direct_free( const char *file, int line, const char *func, const char *what, void *mem )
{
     unsigned int i;

     if (!mem) {
          D_WARN( "%s (NULL) called", __FUNCTION__ );
          return;
     }

     if (!direct_config->debugmem) {
          D_DEBUG_AT( Direct_Mem, "  - number of bytes of %s [%s:%d in %s()] -> %p\n", what, file, line, func, mem );
          free( mem );
          return;
     }


     /* Debug only. */
     pthread_mutex_lock( &alloc_lock );

     for (i=0; i<alloc_count; i++) {
          MemDesc *desc = &alloc_list[i];

          if (desc->mem == mem) {
               free( mem );

               D_DEBUG_AT( Direct_Mem, "  -%6zu bytes [%s:%d in %s()] -> %p '%s'\n",
                           desc->bytes, file, line, func, mem, what );

               if (desc->trace)
                    direct_trace_free_buffer( desc->trace );

               alloc_count--;

               /* FIXME: This can be very slow. */
               if (i < alloc_count)
                    direct_memmove( desc, desc + 1, (alloc_count - i) * sizeof(MemDesc) );

               pthread_mutex_unlock( &alloc_lock );

               return;
          }
     }

     pthread_mutex_unlock( &alloc_lock );

     D_ERROR( "Direct/Mem: Not freeing unknown %p (%s) from [%s:%d in %s()] - corrupt/incomplete list?\n",
              mem, what, file, line, func );
}

char *
direct_strdup( const char* file, int line, const char *func, const char *string )
{
     void    *mem;
     MemDesc *desc;
     size_t   length = strlen( string ) + 1;

     mem = malloc( length );
     D_DEBUG_AT( Direct_Mem, "  +%6zu bytes [%s:%d in %s()] -> %p \"%30s\"\n", length, file, line, func, mem, string );
     if (!mem)
          return NULL;

     direct_memcpy( mem, string, length );

     if (!direct_config->debugmem)
          return mem;


     /* Debug only. */
     pthread_mutex_lock( &alloc_lock );
     desc = allocate_mem_desc();
     pthread_mutex_unlock( &alloc_lock );

     if (desc)
          fill_mem_desc( desc, mem, length, func, file, line, direct_trace_copy_buffer(NULL) );

     return mem;
}

/**********************************************************************************************************************/

#else

void
direct_print_memleaks( void )
{
}

#endif