Logo Search packages:      
Sourcecode: wireshark version File versions  Download package

emem.c

/* emem.c
 * Wireshark memory management and garbage collection functions
 * Ronnie Sahlberg 2005
 *
 * $Id: emem.c 32422 2010-04-08 02:26:56Z guy $
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * This program 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
 * of the License, or (at your option) any later version.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <ctype.h>

#include <time.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <glib.h>

#include "proto.h"
#include "emem.h"

#ifdef _WIN32
#include <windows.h>    /* VirtualAlloc, VirtualProtect */
#include <process.h>    /* getpid */
#endif

/* Print out statistics about our memory allocations? */
/*#define SHOW_EMEM_STATS*/

/* Do we want to use guardpages? if available */
#define WANT_GUARD_PAGES 1

#ifdef WANT_GUARD_PAGES
/* Add guard pages at each end of our allocated memory */
#if defined(HAVE_SYSCONF) && defined(HAVE_MMAP) && defined(HAVE_MPROTECT) && defined(HAVE_STDINT_H)
#include <stdint.h>
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#include <sys/mman.h>
#if defined(MAP_ANONYMOUS)
#define ANON_PAGE_MODE  (MAP_ANONYMOUS|MAP_PRIVATE)
#elif defined(MAP_ANON)
#define ANON_PAGE_MODE  (MAP_ANON|MAP_PRIVATE)
#else
#define ANON_PAGE_MODE  (MAP_PRIVATE)     /* have to map /dev/zero */
#define NEED_DEV_ZERO
#endif
#ifdef NEED_DEV_ZERO
#include <fcntl.h>
static int dev_zero_fd;
#define ANON_FD   dev_zero_fd
#else
#define ANON_FD   -1
#endif
#define USE_GUARD_PAGES 1
#endif
#endif

/* When required, allocate more memory from the OS in this size chunks */
#define EMEM_PACKET_CHUNK_SIZE (10 * 1024 * 1024)

#define EMEM_CANARY_SIZE 8
#define EMEM_CANARY_DATA_SIZE (EMEM_CANARY_SIZE * 2 - 1)

typedef struct _emem_chunk_t {
      struct _emem_chunk_t *next;
      char        *buf;
      unsigned int      amount_free_init;
      unsigned int      amount_free;
      unsigned int      free_offset_init;
      unsigned int      free_offset;
      void        *canary_last;
} emem_chunk_t;

typedef struct _emem_header_t {
      emem_chunk_t *free_list;
      emem_chunk_t *used_list;

      emem_tree_t *trees;           /* only used by se_mem allocator */

      guint8 canary[EMEM_CANARY_DATA_SIZE];
      void *(*memory_alloc)(size_t size, struct _emem_header_t *);

      /*
       * Tools like Valgrind and ElectricFence don't work well with memchunks.
       * Export the following environment variables to make {ep|se}_alloc() allocate each
       * object individually.
       *
       * WIRESHARK_DEBUG_EP_NO_CHUNKS
       * WIRESHARK_DEBUG_SE_NO_CHUNKS
       */
      gboolean debug_use_chunks;

      /* Do we want to use canaries?
       * Export the following environment variables to disable/enable canaries
       *
       * WIRESHARK_DEBUG_EP_NO_CANARY
       * For SE memory use of canary is default off as the memory overhead
       * is considerable.
       * WIRESHARK_DEBUG_SE_USE_CANARY
       */
      gboolean debug_use_canary;

} emem_header_t;

static emem_header_t ep_packet_mem;
static emem_header_t se_packet_mem;

/*
 *  Memory scrubbing is expensive but can be useful to ensure we don't:
 *    - use memory before initializing it
 *    - use memory after freeing it
 *  Export WIRESHARK_DEBUG_SCRUB_MEMORY to turn it on.
 */
static gboolean debug_use_memory_scrubber = FALSE;

#if defined (_WIN32)
static SYSTEM_INFO sysinfo;
static OSVERSIONINFO versinfo;
static int pagesize;
#elif defined(USE_GUARD_PAGES)
static intptr_t pagesize;
#endif /* _WIN32 / USE_GUARD_PAGES */

static void *emem_alloc_chunk(size_t size, emem_header_t *mem);
static void *emem_alloc_glib(size_t size, emem_header_t *mem);

/*
 * Set a canary value to be placed between memchunks.
 */
static void
emem_canary_init(guint8 *canary)
{
      int i;
      static GRand *rand_state = NULL;

      if (rand_state == NULL) {
            rand_state = g_rand_new();
      }
      for (i = 0; i < EMEM_CANARY_DATA_SIZE; i ++) {
            canary[i] = (guint8) g_rand_int_range(rand_state, 1, 0x100);
      }
      return;
}

static void *
emem_canary_next(guint8 *mem_canary, guint8 *canary, int *len)
{
      void *ptr;
      int i;

      for (i = 0; i < EMEM_CANARY_SIZE-1; i++)
            if (mem_canary[i] != canary[i])
                  return (void *) -1;

      for (; i < EMEM_CANARY_DATA_SIZE; i++) {
            if (canary[i] == '\0') {
                  memcpy(&ptr, &canary[i+1], sizeof(void *));

                  if (len)
                        *len = i + 1 + sizeof(void *);
                  return ptr;
            }

            if (mem_canary[i] != canary[i])
                  return (void *) -1;
      }

      return (void *) -1;
}

/*
 * Given an allocation size, return the amount of padding needed for
 * the canary value.
 */
static guint8
emem_canary_pad (size_t allocation)
{
      guint8 pad;

      pad = EMEM_CANARY_SIZE - (allocation % EMEM_CANARY_SIZE);
      if (pad < EMEM_CANARY_SIZE)
            pad += EMEM_CANARY_SIZE;

      return pad;
}

/* used for debugging canaries, will block */
#ifdef DEBUG_INTENSE_CANARY_CHECKS
gboolean intense_canary_checking = FALSE;

/*  used to intensivelly check ep canaries
 */
void
ep_check_canary_integrity(const char* fmt, ...)
{
      va_list ap;
      static gchar there[128] = {
            'L','a','u','n','c','h',0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 };
      gchar here[128];
      emem_chunk_t* npc = NULL;

      if (! intense_canary_checking ) return;

      va_start(ap,fmt);
      g_vsnprintf(here, sizeof(here), fmt, ap);
      va_end(ap);

      for (npc = ep_packet_mem.free_list; npc != NULL; npc = npc->next) {
            void *canary_next = npc->canary_last;

            while (canary_next != NULL) {
                  canary_next = emem_canary_next(ep_packet_mem.canary, canary_next, NULL);
                  /* XXX, check if canary_last is inside allocated memory? */

                  if (npc->canary_last == (void *) -1)
                        g_error("Per-packet memory corrupted\nbetween: %s\nand: %s", there, here);
            }
      }

      g_strlcpy(there, here, sizeof(there));
}
#endif

static void
emem_init_chunk(emem_header_t *mem)
{
      if (mem->debug_use_canary)
            emem_canary_init(mem->canary);

      if (mem->debug_use_chunks)
            mem->memory_alloc = emem_alloc_chunk;
      else
            mem->memory_alloc = emem_alloc_glib;
}


/* Initialize the packet-lifetime memory allocation pool.
 * This function should be called only once when Wireshark or TShark starts
 * up.
 */
static void
ep_init_chunk(void)
{
      ep_packet_mem.free_list=NULL;
      ep_packet_mem.used_list=NULL;
      ep_packet_mem.trees=NULL;     /* not used by this allocator */

      ep_packet_mem.debug_use_chunks = (getenv("WIRESHARK_DEBUG_EP_NO_CHUNKS") == NULL);
      ep_packet_mem.debug_use_canary = ep_packet_mem.debug_use_chunks && (getenv("WIRESHARK_DEBUG_EP_NO_CANARY") == NULL);

#ifdef DEBUG_INTENSE_CANARY_CHECKS
      intense_canary_checking = (getenv("WIRESHARK_DEBUG_EP_INTENSE_CANARY") != NULL);
#endif

      emem_init_chunk(&ep_packet_mem);
}

/* Initialize the capture-lifetime memory allocation pool.
 * This function should be called only once when Wireshark or TShark starts
 * up.
 */
static void
se_init_chunk(void)
{
      se_packet_mem.free_list = NULL;
      se_packet_mem.used_list = NULL;
      se_packet_mem.trees = NULL;

      se_packet_mem.debug_use_chunks = (getenv("WIRESHARK_DEBUG_SE_NO_CHUNKS") == NULL);
      se_packet_mem.debug_use_canary = se_packet_mem.debug_use_chunks && (getenv("WIRESHARK_DEBUG_SE_USE_CANARY") != NULL);

      emem_init_chunk(&se_packet_mem);
}

/*  Initialize all the allocators here.
 *  This function should be called only once when Wireshark or TShark starts
 *  up.
 */
void
emem_init(void)
{
      ep_init_chunk();
      se_init_chunk();

      if (getenv("WIRESHARK_DEBUG_SCRUB_MEMORY"))
            debug_use_memory_scrubber  = TRUE;

#if defined (_WIN32)
      /* Set up our guard page info for Win32 */
      GetSystemInfo(&sysinfo);
      pagesize = sysinfo.dwPageSize;

      /* calling GetVersionEx using the OSVERSIONINFO structure.
       * OSVERSIONINFOEX requires Win NT4 with SP6 or newer NT Versions.
       * OSVERSIONINFOEX will fail on Win9x and older NT Versions.
       * See also:
       * http://msdn.microsoft.com/library/en-us/sysinfo/base/getversionex.asp
       * http://msdn.microsoft.com/library/en-us/sysinfo/base/osversioninfo_str.asp
       * http://msdn.microsoft.com/library/en-us/sysinfo/base/osversioninfoex_str.asp
       */
      versinfo.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
      GetVersionEx(&versinfo);

#elif defined(USE_GUARD_PAGES)
      pagesize = sysconf(_SC_PAGESIZE);
#ifdef NEED_DEV_ZERO
      dev_zero_fd = ws_open("/dev/zero", O_RDWR);
      g_assert(dev_zero_fd != -1);
#endif
#endif /* _WIN32 / USE_GUARD_PAGES */
}

#ifdef SHOW_EMEM_STATS
#define NUM_ALLOC_DIST 10
static guint allocations[NUM_ALLOC_DIST] = { 0 };
static guint total_no_chunks = 0;

static void
print_alloc_stats()
{
      guint num_chunks = 0;
      guint num_allocs = 0;
      guint total_used = 0;
      guint total_allocation = 0;
      guint total_free = 0;
      guint used_for_canaries = 0;
      guint total_headers;
      guint i;
      emem_chunk_t *chunk;
      guint total_space_allocated_from_os, total_space_wasted;
      gboolean ep_stat=TRUE;

      fprintf(stderr, "\n-------- EP allocator statistics --------\n");
      fprintf(stderr, "%s chunks, %s canaries, %s memory scrubber\n",
             ep_packet_mem.debug_use_chunks ? "Using" : "Not using",
             ep_packet_mem.debug_use_canary ? "using" : "not using",
             debug_use_memory_scrubber ? "using" : "not using");

      if (! (ep_packet_mem.free_list || !ep_packet_mem.used_list)) {
            fprintf(stderr, "No memory allocated\n");
            ep_stat = FALSE;
      }
      if (ep_packet_mem.debug_use_chunks && ep_stat) {
            /* Nothing interesting without chunks */
            /*  Only look at the used_list since those chunks are fully
             *  used.  Looking at the free list would skew our view of what
             *  we have wasted.
             */
            for (chunk = ep_packet_mem.used_list; chunk; chunk = chunk->next) {
                  num_chunks++;
                  total_used += (chunk->amount_free_init - chunk->amount_free);
                  total_allocation += chunk->amount_free_init;
                  total_free += chunk->amount_free;
            }
            if (num_chunks > 0) {
                  fprintf (stderr, "\n");
                  fprintf (stderr, "\n---- Buffer space ----\n");
                  fprintf (stderr, "\tChunk allocation size: %10u\n", EMEM_PACKET_CHUNK_SIZE);
                  fprintf (stderr, "\t*    Number of chunks: %10u\n", num_chunks);
                  fprintf (stderr, "\t-------------------------------------------\n");
                  fprintf (stderr, "\t= %u (%u including guard pages) total space used for buffers\n",
                  total_allocation, EMEM_PACKET_CHUNK_SIZE * num_chunks);
                  fprintf (stderr, "\t-------------------------------------------\n");
                  total_space_allocated_from_os = total_allocation
                        + sizeof(emem_chunk_t) * num_chunks;
                  fprintf (stderr, "Total allocated from OS: %u\n\n",
                        total_space_allocated_from_os);
            }else{
                  fprintf (stderr, "No fully used chunks, nothing to do\n");
            }
            /* Reset stats */
            num_chunks = 0;
            num_allocs = 0;
            total_used = 0;
            total_allocation = 0;
            total_free = 0;
            used_for_canaries = 0;
      }


      fprintf(stderr, "\n-------- SE allocator statistics --------\n");
      fprintf(stderr, "Total number of chunk allocations %u\n",
            total_no_chunks);
      fprintf(stderr, "%s chunks, %s canaries\n",
             se_packet_mem.debug_use_chunks ? "Using" : "Not using",
             se_packet_mem.debug_use_canary ? "using" : "not using");

      if (! (se_packet_mem.free_list || !se_packet_mem.used_list)) {
            fprintf(stderr, "No memory allocated\n");
            return;
      }

      if (!se_packet_mem.debug_use_chunks )
            return; /* Nothing interesting without chunks?? */

      /*  Only look at the used_list since those chunks are fully used.
       *  Looking at the free list would skew our view of what we have wasted.
       */
      for (chunk = se_packet_mem.used_list; chunk; chunk = chunk->next) {
            num_chunks++;
            total_used += (chunk->amount_free_init - chunk->amount_free);
            total_allocation += chunk->amount_free_init;
            total_free += chunk->amount_free;

            if (se_packet_mem.debug_use_canary){
                  void *ptr = chunk->canary_last;
                  int len;

                  while (ptr != NULL) {
                        ptr = emem_canary_next(se_packet_mem.canary, ptr, &len);

                        if (ptr == (void *) -1)
                              g_error("Memory corrupted");
                        used_for_canaries += len;
                  }
            }
      }

      if (num_chunks == 0) {

            fprintf (stderr, "No fully used chunks, nothing to do\n");
            return;
      }

      fprintf (stderr, "\n");
      fprintf (stderr, "---------- Allocations from the OS ----------\n");
      fprintf (stderr, "---- Headers ----\n");
      fprintf (stderr, "\t(    Chunk header size: %10lu\n",
             sizeof(emem_chunk_t));
      fprintf (stderr, "\t*     Number of chunks: %10u\n", num_chunks);
      fprintf (stderr, "\t-------------------------------------------\n");

      total_headers = sizeof(emem_chunk_t) * num_chunks;
      fprintf (stderr, "\t= %u bytes used for headers\n", total_headers);
      fprintf (stderr, "\n---- Buffer space ----\n");
      fprintf (stderr, "\tChunk allocation size: %10u\n",
             EMEM_PACKET_CHUNK_SIZE);
      fprintf (stderr, "\t*    Number of chunks: %10u\n", num_chunks);
      fprintf (stderr, "\t-------------------------------------------\n");
      fprintf (stderr, "\t= %u (%u including guard pages) bytes used for buffers\n",
            total_allocation, EMEM_PACKET_CHUNK_SIZE * num_chunks);
      fprintf (stderr, "\t-------------------------------------------\n");
      total_space_allocated_from_os = (EMEM_PACKET_CHUNK_SIZE * num_chunks)
                              + total_headers;
      fprintf (stderr, "Total bytes allocated from the OS: %u\n\n",
            total_space_allocated_from_os);

      for (i = 0; i < NUM_ALLOC_DIST; i++)
            num_allocs += allocations[i];

      fprintf (stderr, "---------- Allocations from the SE pool ----------\n");
      fprintf (stderr, "                Number of SE allocations: %10u\n",
             num_allocs);
      fprintf (stderr, "             Bytes used (incl. canaries): %10u\n",
             total_used);
      fprintf (stderr, "                 Bytes used for canaries: %10u\n",
             used_for_canaries);
      fprintf (stderr, "Bytes unused (wasted, excl. guard pages): %10u\n",
             total_allocation - total_used);
      fprintf (stderr, "Bytes unused (wasted, incl. guard pages): %10u\n\n",
             total_space_allocated_from_os - total_used);

      fprintf (stderr, "---------- Statistics ----------\n");
      fprintf (stderr, "Average SE allocation size (incl. canaries): %6.2f\n",
            (float)total_used/(float)num_allocs);
      fprintf (stderr, "Average SE allocation size (excl. canaries): %6.2f\n",
            (float)(total_used - used_for_canaries)/(float)num_allocs);
      fprintf (stderr, "        Average wasted bytes per allocation: %6.2f\n",
            (total_allocation - total_used)/(float)num_allocs);
      total_space_wasted = (total_allocation - total_used)
            + (sizeof(emem_chunk_t));
      fprintf (stderr, " Space used for headers + unused allocation: %8u\n",
            total_space_wasted);
      fprintf (stderr, "--> %% overhead/waste: %4.2f\n",
            100 * (float)total_space_wasted/(float)total_space_allocated_from_os);

      fprintf (stderr, "\nAllocation distribution (sizes include canaries):\n");
      for (i = 0; i < (NUM_ALLOC_DIST-1); i++)
            fprintf (stderr, "size < %5d: %8u\n", 32<<i, allocations[i]);
      fprintf (stderr, "size > %5d: %8u\n", 32<<i, allocations[i]);
}
#endif

static gboolean
emem_verify_pointer(emem_header_t *hdr, const void *ptr)
{
      const gchar *cptr = ptr;
      emem_chunk_t *used_list[2];
      guint8 used_list_idx;
      emem_chunk_t *chunk;

      used_list[0] = hdr->free_list;
      used_list[1] = hdr->used_list;

      for (used_list_idx=0; used_list_idx < G_N_ELEMENTS(used_list); ++used_list_idx) {
            chunk = used_list[used_list_idx];
            for ( ; chunk ; chunk = chunk->next) {
                  if (cptr >= (chunk->buf + chunk->free_offset_init) &&
                        cptr < (chunk->buf + chunk->free_offset))
                        return TRUE;
            }
      }

      return FALSE;
}

gboolean
ep_verify_pointer(const void *ptr)
{
      return emem_verify_pointer(&ep_packet_mem, ptr);
}

gboolean
se_verify_pointer(const void *ptr)
{
      return emem_verify_pointer(&se_packet_mem, ptr);
}

static void
emem_scrub_memory(char *buf, size_t size, gboolean alloc)
{
      guint scrubbed_value;
      guint offset;

      if (!debug_use_memory_scrubber)
            return;

      if (alloc) /* this memory is being allocated */
            scrubbed_value = 0xBADDCAFE;
      else /* this memory is being freed */
            scrubbed_value = 0xDEADBEEF;

      /*  We shouldn't need to check the alignment of the starting address
       *  since this is malloc'd memory (or 'pagesize' bytes into malloc'd
       *  memory).
       */

      /* XXX - We might want to use memset here in order to avoid problems on
       * alignment-sensitive platforms, e.g.
       * http://stackoverflow.com/questions/108866/is-there-memset-that-accepts-integers-larger-than-char
       */

      for (offset = 0; offset + sizeof(guint) <= size; offset += sizeof(guint))
            *(guint*)(buf+offset) = scrubbed_value;

      /* Initialize the last bytes, if any */
      if (offset < size) {
            *(guint8*)(buf+offset) = scrubbed_value >> 24;
            offset++;
            if (offset < size) {
                  *(guint8*)(buf+offset) = (scrubbed_value >> 16) & 0xFF;
                  offset++;
                  if (offset < size) {
                        *(guint8*)(buf+offset) = (scrubbed_value >> 8) & 0xFF;
                        offset++;
                  }
            }
      }


}

static emem_chunk_t *
emem_create_chunk(void) {
#if defined (_WIN32)
      BOOL ret;
      char *buf_end, *prot1, *prot2;
      DWORD oldprot;
#elif defined(USE_GUARD_PAGES)
      int ret;
      char *buf_end, *prot1, *prot2;
#endif /* _WIN32 / USE_GUARD_PAGES */
      emem_chunk_t *npc;

      npc = g_new(emem_chunk_t, 1);
      npc->next = NULL;
      npc->canary_last = NULL;

#if defined (_WIN32)
      /*
       * MSDN documents VirtualAlloc/VirtualProtect at
       * http://msdn.microsoft.com/library/en-us/memory/base/creating_guard_pages.asp
       */

      /* XXX - is MEM_COMMIT|MEM_RESERVE correct? */
      npc->buf = VirtualAlloc(NULL, EMEM_PACKET_CHUNK_SIZE,
            MEM_COMMIT|MEM_RESERVE, PAGE_READWRITE);

      if (npc->buf == NULL) {
            g_free(npc);
            THROW(OutOfMemoryError);
      }

#elif defined(USE_GUARD_PAGES)
      npc->buf = mmap(NULL, EMEM_PACKET_CHUNK_SIZE,
            PROT_READ|PROT_WRITE, ANON_PAGE_MODE, ANON_FD, 0);

      if (npc->buf == MAP_FAILED) {
            g_free(npc);
            THROW(OutOfMemoryError);
      }

#else /* Is there a draft in here? */
      npc->buf = g_malloc(EMEM_PACKET_CHUNK_SIZE);
      /* g_malloc() can't fail */
#endif

#ifdef SHOW_EMEM_STATS
      total_no_chunks++;
#endif

#if defined (_WIN32)
      buf_end = npc->buf + EMEM_PACKET_CHUNK_SIZE;

      /* Align our guard pages on page-sized boundaries */
      prot1 = (char *) ((((int) npc->buf + pagesize - 1) / pagesize) * pagesize);
      prot2 = (char *) ((((int) buf_end - (1 * pagesize)) / pagesize) * pagesize);

      ret = VirtualProtect(prot1, pagesize, PAGE_NOACCESS, &oldprot);
      g_assert(ret != 0 || versinfo.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS);
      ret = VirtualProtect(prot2, pagesize, PAGE_NOACCESS, &oldprot);
      g_assert(ret != 0 || versinfo.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS);

      npc->amount_free_init = (unsigned int) (prot2 - prot1 - pagesize);
      npc->free_offset_init = (unsigned int) (prot1 - npc->buf) + pagesize;
#elif defined(USE_GUARD_PAGES)
      buf_end = npc->buf + EMEM_PACKET_CHUNK_SIZE;

      /* Align our guard pages on page-sized boundaries */
      prot1 = (char *) ((((intptr_t) npc->buf + pagesize - 1) / pagesize) * pagesize);
      prot2 = (char *) ((((intptr_t) buf_end - (1 * pagesize)) / pagesize) * pagesize);

      ret = mprotect(prot1, pagesize, PROT_NONE);
      g_assert(ret != -1);
      ret = mprotect(prot2, pagesize, PROT_NONE);
      g_assert(ret != -1);

      npc->amount_free_init = prot2 - prot1 - pagesize;
      npc->free_offset_init = (prot1 - npc->buf) + pagesize;
#else 
      npc->amount_free_init = EMEM_PACKET_CHUNK_SIZE;
      npc->free_offset_init = 0;
#endif /* USE_GUARD_PAGES */

      npc->amount_free = npc->amount_free_init;
      npc->free_offset = npc->free_offset_init;
      return npc;
}

static void *
emem_alloc_chunk(size_t size, emem_header_t *mem)
{
      void *buf;

      size_t asize = size;
      gboolean use_canary = mem->debug_use_canary;
      guint8 pad;
      emem_chunk_t *free_list;

      /* Round up to an 8 byte boundary. Make sure we have at least
       * 8 pad bytes for our canary.
       */
       if (use_canary) {
            pad = emem_canary_pad(asize);
            asize += sizeof(void *);
      } else
            pad = (G_MEM_ALIGN - (asize & (G_MEM_ALIGN-1))) & (G_MEM_ALIGN-1);

      asize += pad;

#ifdef SHOW_EMEM_STATS
      /* Do this check here so we can include the canary size */
      if (mem == &se_packet_mem) {
            if (asize < 32)
                  allocations[0]++;
            else if (asize < 64)
                  allocations[1]++;
            else if (asize < 128)
                  allocations[2]++;
            else if (asize < 256)
                  allocations[3]++;
            else if (asize < 512)
                  allocations[4]++;
            else if (asize < 1024)
                  allocations[5]++;
            else if (asize < 2048)
                  allocations[6]++;
            else if (asize < 4096)
                  allocations[7]++;
            else if (asize < 8192)
                  allocations[8]++;
            else if (asize < 16384)
                  allocations[8]++;
            else
                  allocations[(NUM_ALLOC_DIST-1)]++;
      }
#endif

      /* make sure we dont try to allocate too much (arbitrary limit) */
      DISSECTOR_ASSERT(size<(EMEM_PACKET_CHUNK_SIZE>>2));

      if (!mem->free_list)
            mem->free_list = emem_create_chunk();

      /* oops, we need to allocate more memory to serve this request
       * than we have free. move this node to the used list and try again
       */
      if(asize > mem->free_list->amount_free) {
            emem_chunk_t *npc;
            npc=mem->free_list;
            mem->free_list=mem->free_list->next;
            npc->next=mem->used_list;
            mem->used_list=npc;

            if (!mem->free_list)
                  mem->free_list = emem_create_chunk();
      }

      free_list = mem->free_list;

      buf = free_list->buf + free_list->free_offset;

      free_list->amount_free -= (unsigned int) asize;
      free_list->free_offset += (unsigned int) asize;

      if (use_canary) {
            char *cptr = (char *)buf + size;

            memcpy(cptr, mem->canary, pad-1);
            cptr[pad-1] = '\0';
            memcpy(cptr + pad, &free_list->canary_last, sizeof(void *));

            free_list->canary_last = cptr;
      }

      return buf;
}

static void *
emem_alloc_glib(size_t size, emem_header_t *mem)
{
      emem_chunk_t *npc;

      npc=g_new(emem_chunk_t, 1);
      npc->next=mem->used_list;
      npc->buf=g_malloc(size);
      npc->canary_last = NULL;
      mem->used_list=npc;
      /* There's no padding/alignment involved (from our point of view) when
       * we fetch the memory directly from the system pool, so WYSIWYG */
      npc->free_offset = npc->free_offset_init = 0;
      npc->amount_free = npc->amount_free_init = (unsigned int) size;

      return npc->buf;
}

/* allocate 'size' amount of memory. */
static void *
emem_alloc(size_t size, emem_header_t *mem)
{
      void *buf = mem->memory_alloc(size, mem);

      /*  XXX - this is a waste of time if the allocator function is going to
       *  memset this straight back to 0.
       */
      emem_scrub_memory(buf, size, TRUE);

      return buf;
}

/* allocate 'size' amount of memory with an allocation lifetime until the
 * next packet.
 */
void *
ep_alloc(size_t size)
{
      return emem_alloc(size, &ep_packet_mem);
}

/* allocate 'size' amount of memory with an allocation lifetime until the
 * next capture.
 */
void *
se_alloc(size_t size)
{
      return emem_alloc(size, &se_packet_mem);
}

void *
ep_alloc0(size_t size)
{
      return memset(ep_alloc(size),'\0',size);
}

gchar *
ep_strdup(const gchar* src)
{
      guint len = (guint) strlen(src);
      gchar* dst;

      dst = memcpy(ep_alloc(len+1), src, len+1);

      return dst;
}

gchar *
ep_strndup(const gchar* src, size_t len)
{
      gchar* dst = ep_alloc(len+1);
      guint i;

      for (i = 0; (i < len) && src[i]; i++)
            dst[i] = src[i];

      dst[i] = '\0';

      return dst;
}

void *
ep_memdup(const void* src, size_t len)
{
      return memcpy(ep_alloc(len), src, len);
}

gchar *
ep_strdup_vprintf(const gchar* fmt, va_list ap)
{
      va_list ap2;
      gsize len;
      gchar* dst;

      G_VA_COPY(ap2, ap);

      len = g_printf_string_upper_bound(fmt, ap);

      dst = ep_alloc(len+1);
      g_vsnprintf (dst, (gulong) len, fmt, ap2);
      va_end(ap2);

      return dst;
}

gchar *
ep_strdup_printf(const gchar* fmt, ...)
{
      va_list ap;
      gchar* dst;

      va_start(ap,fmt);
      dst = ep_strdup_vprintf(fmt, ap);
      va_end(ap);
      return dst;
}

gchar **
ep_strsplit(const gchar* string, const gchar* sep, int max_tokens)
{
      gchar* splitted;
      gchar* s;
      guint tokens;
      guint str_len;
      guint sep_len;
      guint i;
      gchar** vec;
      enum { AT_START, IN_PAD, IN_TOKEN } state;
      guint curr_tok = 0;

      if (    ! string
           || ! sep
           || ! sep[0])
            return NULL;

      s = splitted = ep_strdup(string);
      str_len = (guint) strlen(splitted);
      sep_len = (guint) strlen(sep);

      if (max_tokens < 1) max_tokens = INT_MAX;

      tokens = 1;


      while (tokens <= (guint)max_tokens && ( s = strstr(s,sep) )) {
            tokens++;

            for(i=0; i < sep_len; i++ )
                  s[i] = '\0';

            s += sep_len;

      }

      vec = ep_alloc_array(gchar*,tokens+1);
      state = AT_START;

      for (i=0; i< str_len; i++) {
            switch(state) {
                  case AT_START:
                        switch(splitted[i]) {
                              case '\0':
                                    state  = IN_PAD;
                                    continue;
                              default:
                                    vec[curr_tok] = &(splitted[i]);
                                    curr_tok++;
                                    state = IN_TOKEN;
                                    continue;
                        }
                  case IN_TOKEN:
                        switch(splitted[i]) {
                              case '\0':
                                    state = IN_PAD;
                              default:
                                    continue;
                        }
                  case IN_PAD:
                        switch(splitted[i]) {
                              default:
                                    vec[curr_tok] = &(splitted[i]);
                                    curr_tok++;
                                    state = IN_TOKEN;
                              case '\0':
                                    continue;
                        }
            }
      }

      vec[curr_tok] = NULL;

      return vec;
}



void *
se_alloc0(size_t size)
{
      return memset(se_alloc(size),'\0',size);
}

/* If str is NULL, just return the string "<NULL>" so that the callers dont
 * have to bother checking it.
 */
gchar *
se_strdup(const gchar* src)
{
      guint len;
      gchar* dst;

      if(!src)
            return "<NULL>";

      len = (guint) strlen(src);
      dst = memcpy(se_alloc(len+1), src, len+1);

      return dst;
}

gchar *
se_strndup(const gchar* src, size_t len)
{
      gchar* dst = se_alloc(len+1);
      guint i;

      for (i = 0; (i < len) && src[i]; i++)
            dst[i] = src[i];

      dst[i] = '\0';

      return dst;
}

void *
se_memdup(const void* src, size_t len)
{
      return memcpy(se_alloc(len), src, len);
}

gchar *
se_strdup_vprintf(const gchar* fmt, va_list ap)
{
      va_list ap2;
      gsize len;
      gchar* dst;

      G_VA_COPY(ap2, ap);

      len = g_printf_string_upper_bound(fmt, ap);

      dst = se_alloc(len+1);
      g_vsnprintf (dst, (gulong) len, fmt, ap2);
      va_end(ap2);

      return dst;
}

gchar *
se_strdup_printf(const gchar* fmt, ...)
{
      va_list ap;
      gchar* dst;

      va_start(ap,fmt);
      dst = se_strdup_vprintf(fmt, ap);
      va_end(ap);
      return dst;
}

/* release all allocated memory back to the pool. */
static void
emem_free_all(emem_header_t *mem)
{
      gboolean use_chunks = mem->debug_use_chunks;

      emem_chunk_t *npc;
      emem_tree_t *tree_list;

      /* move all used chunks over to the free list */
      while(mem->used_list){
            npc=mem->used_list;
            mem->used_list=mem->used_list->next;
            npc->next=mem->free_list;
            mem->free_list=npc;
      }

      /* clear them all out */
      npc = mem->free_list;
      while (npc != NULL) {
            if (use_chunks) {
                  while (npc->canary_last != NULL) {
                        npc->canary_last = emem_canary_next(mem->canary, npc->canary_last, NULL);
                        /* XXX, check if canary_last is inside allocated memory? */

                        if (npc->canary_last == (void *) -1)
                              g_error("Memory corrupted");
                  }

                  emem_scrub_memory((npc->buf + npc->free_offset_init),
                                (npc->free_offset - npc->free_offset_init),
                                FALSE);

                  npc->amount_free = npc->amount_free_init;
                  npc->free_offset = npc->free_offset_init;
                  npc = npc->next;
            } else {
                  emem_chunk_t *next = npc->next;

                  emem_scrub_memory(npc->buf, npc->amount_free_init, FALSE);

                  g_free(npc->buf);
                  g_free(npc);
                  npc = next;
            }
      }

      if (!use_chunks) {
            /* We've freed all this memory already */
            mem->free_list = NULL;
      }

      /* release/reset all allocated trees */
      for(tree_list=mem->trees;tree_list;tree_list=tree_list->next){
            tree_list->tree=NULL;
      }
}

/* release all allocated memory back to the pool. */
void
ep_free_all(void)
{
      emem_free_all(&ep_packet_mem);
}

/* release all allocated memory back to the pool. */
void
se_free_all(void)
{
#ifdef SHOW_EMEM_STATS
      print_alloc_stats();
#endif

      emem_free_all(&se_packet_mem);
}

ep_stack_t
ep_stack_new(void) {
      ep_stack_t s = ep_new(struct _ep_stack_frame_t*);
      *s = ep_new0(struct _ep_stack_frame_t);
      return s;
}

/*  for ep_stack_t we'll keep the popped frames so we reuse them instead
of allocating new ones.
*/

void *
ep_stack_push(ep_stack_t stack, void* data)
{
      struct _ep_stack_frame_t* frame;
      struct _ep_stack_frame_t* head = (*stack);

      if (head->above) {
            frame = head->above;
      } else {
            frame = ep_new(struct _ep_stack_frame_t);
            head->above = frame;
            frame->below = head;
            frame->above = NULL;
      }

      frame->payload = data;
      (*stack) = frame;

      return data;
}

void *
ep_stack_pop(ep_stack_t stack)
{

      if ((*stack)->below) {
            (*stack) = (*stack)->below;
            return (*stack)->above->payload;
      } else {
            return NULL;
      }
}

emem_tree_t *
se_tree_create(int type, const char *name)
{
      emem_tree_t *tree_list;

      tree_list=g_malloc(sizeof(emem_tree_t));
      tree_list->next=se_packet_mem.trees;
      tree_list->type=type;
      tree_list->tree=NULL;
      tree_list->name=name;
      tree_list->malloc=se_alloc;
      se_packet_mem.trees=tree_list;

      return tree_list;
}

void *
emem_tree_lookup32(emem_tree_t *se_tree, guint32 key)
{
      emem_tree_node_t *node;

      node=se_tree->tree;

      while(node){
            if(key==node->key32){
                  return node->data;
            }
            if(key<node->key32){
                  node=node->left;
                  continue;
            }
            if(key>node->key32){
                  node=node->right;
                  continue;
            }
      }
      return NULL;
}

void *
emem_tree_lookup32_le(emem_tree_t *se_tree, guint32 key)
{
      emem_tree_node_t *node;

      node=se_tree->tree;

      if(!node){
            return NULL;
      }


      while(node){
            if(key==node->key32){
                  return node->data;
            }
            if(key<node->key32){
                  if(node->left){
                        node=node->left;
                        continue;
                  } else {
                        break;
                  }
            }
            if(key>node->key32){
                  if(node->right){
                        node=node->right;
                        continue;
                  } else {
                        break;
                  }
            }
      }


      if(!node){
            return NULL;
      }

      /* If we are still at the root of the tree this means that this node
       * is either smaller than the search key and then we return this
       * node or else there is no smaller key available and then
       * we return NULL.
       */
      if(!node->parent){
            if(key>node->key32){
                  return node->data;
            } else {
                  return NULL;
            }
      }

      if(node->parent->left==node){
            /* left child */

            if(key>node->key32){
                  /* if this is a left child and its key is smaller than
                   * the search key, then this is the node we want.
                   */
                  return node->data;
            } else {
                  /* if this is a left child and its key is bigger than
                   * the search key, we have to check if any
                   * of our ancestors are smaller than the search key.
                   */
                  while(node){
                        if(key>node->key32){
                              return node->data;
                        }
                        node=node->parent;
                  }
                  return NULL;
            }
      } else {
            /* right child */

            if(node->key32<key){
                  /* if this is the right child and its key is smaller
                   * than the search key then this is the one we want.
                   */
                  return node->data;
            } else {
                  /* if this is the right child and its key is larger
                   * than the search key then our parent is the one we
                   * want.
                   */
                  return node->parent->data;
            }
      }

}


static inline emem_tree_node_t *
emem_tree_parent(emem_tree_node_t *node)
{
      return node->parent;
}

static inline emem_tree_node_t *
emem_tree_grandparent(emem_tree_node_t *node)
{
      emem_tree_node_t *parent;

      parent=emem_tree_parent(node);
      if(parent){
            return parent->parent;
      }
      return NULL;
}

static inline emem_tree_node_t *
emem_tree_uncle(emem_tree_node_t *node)
{
      emem_tree_node_t *parent, *grandparent;

      parent=emem_tree_parent(node);
      if(!parent){
            return NULL;
      }
      grandparent=emem_tree_parent(parent);
      if(!grandparent){
            return NULL;
      }
      if(parent==grandparent->left){
            return grandparent->right;
      }
      return grandparent->left;
}

static inline void rb_insert_case1(emem_tree_t *se_tree, emem_tree_node_t *node);
static inline void rb_insert_case2(emem_tree_t *se_tree, emem_tree_node_t *node);

static inline void
rotate_left(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      if(node->parent){
            if(node->parent->left==node){
                  node->parent->left=node->right;
            } else {
                  node->parent->right=node->right;
            }
      } else {
            se_tree->tree=node->right;
      }
      node->right->parent=node->parent;
      node->parent=node->right;
      node->right=node->right->left;
      if(node->right){
            node->right->parent=node;
      }
      node->parent->left=node;
}

static inline void
rotate_right(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      if(node->parent){
            if(node->parent->left==node){
                  node->parent->left=node->left;
            } else {
                  node->parent->right=node->left;
            }
      } else {
            se_tree->tree=node->left;
      }
      node->left->parent=node->parent;
      node->parent=node->left;
      node->left=node->left->right;
      if(node->left){
            node->left->parent=node;
      }
      node->parent->right=node;
}

static inline void
rb_insert_case5(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      emem_tree_node_t *grandparent;
      emem_tree_node_t *parent;

      parent=emem_tree_parent(node);
      grandparent=emem_tree_parent(parent);
      parent->u.rb_color=EMEM_TREE_RB_COLOR_BLACK;
      grandparent->u.rb_color=EMEM_TREE_RB_COLOR_RED;
      if( (node==parent->left) && (parent==grandparent->left) ){
            rotate_right(se_tree, grandparent);
      } else {
            rotate_left(se_tree, grandparent);
      }
}

static inline void
rb_insert_case4(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      emem_tree_node_t *grandparent;
      emem_tree_node_t *parent;

      parent=emem_tree_parent(node);
      grandparent=emem_tree_parent(parent);
      if(!grandparent){
            return;
      }
      if( (node==parent->right) && (parent==grandparent->left) ){
            rotate_left(se_tree, parent);
            node=node->left;
      } else if( (node==parent->left) && (parent==grandparent->right) ){
            rotate_right(se_tree, parent);
            node=node->right;
      }
      rb_insert_case5(se_tree, node);
}

static inline void
rb_insert_case3(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      emem_tree_node_t *grandparent;
      emem_tree_node_t *parent;
      emem_tree_node_t *uncle;

      uncle=emem_tree_uncle(node);
      if(uncle && (uncle->u.rb_color==EMEM_TREE_RB_COLOR_RED)){
            parent=emem_tree_parent(node);
            parent->u.rb_color=EMEM_TREE_RB_COLOR_BLACK;
            uncle->u.rb_color=EMEM_TREE_RB_COLOR_BLACK;
            grandparent=emem_tree_grandparent(node);
            grandparent->u.rb_color=EMEM_TREE_RB_COLOR_RED;
            rb_insert_case1(se_tree, grandparent);
      } else {
            rb_insert_case4(se_tree, node);
      }
}

static inline void
rb_insert_case2(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      emem_tree_node_t *parent;

      parent=emem_tree_parent(node);
      /* parent is always non-NULL here */
      if(parent->u.rb_color==EMEM_TREE_RB_COLOR_BLACK){
            return;
      }
      rb_insert_case3(se_tree, node);
}

static inline void
rb_insert_case1(emem_tree_t *se_tree, emem_tree_node_t *node)
{
      emem_tree_node_t *parent;

      parent=emem_tree_parent(node);
      if(!parent){
            node->u.rb_color=EMEM_TREE_RB_COLOR_BLACK;
            return;
      }
      rb_insert_case2(se_tree, node);
}

/* insert a new node in the tree. if this node matches an already existing node
 * then just replace the data for that node */
void
emem_tree_insert32(emem_tree_t *se_tree, guint32 key, void *data)
{
      emem_tree_node_t *node;

      node=se_tree->tree;

      /* is this the first node ?*/
      if(!node){
            node=se_tree->malloc(sizeof(emem_tree_node_t));
            switch(se_tree->type){
            case EMEM_TREE_TYPE_RED_BLACK:
                  node->u.rb_color=EMEM_TREE_RB_COLOR_BLACK;
                  break;
            }
            node->parent=NULL;
            node->left=NULL;
            node->right=NULL;
            node->key32=key;
            node->data=data;
            node->u.is_subtree = EMEM_TREE_NODE_IS_DATA;
            se_tree->tree=node;
            return;
      }

      /* it was not the new root so walk the tree until we find where to
       * insert this new leaf.
       */
      while(1){
            /* this node already exists, so just replace the data pointer*/
            if(key==node->key32){
                  node->data=data;
                  return;
            }
            if(key<node->key32) {
                  if(!node->left){
                        /* new node to the left */
                        emem_tree_node_t *new_node;
                        new_node=se_tree->malloc(sizeof(emem_tree_node_t));
                        node->left=new_node;
                        new_node->parent=node;
                        new_node->left=NULL;
                        new_node->right=NULL;
                        new_node->key32=key;
                        new_node->data=data;
                        new_node->u.is_subtree=EMEM_TREE_NODE_IS_DATA;
                        node=new_node;
                        break;
                  }
                  node=node->left;
                  continue;
            }
            if(key>node->key32) {
                  if(!node->right){
                        /* new node to the right */
                        emem_tree_node_t *new_node;
                        new_node=se_tree->malloc(sizeof(emem_tree_node_t));
                        node->right=new_node;
                        new_node->parent=node;
                        new_node->left=NULL;
                        new_node->right=NULL;
                        new_node->key32=key;
                        new_node->data=data;
                        new_node->u.is_subtree=EMEM_TREE_NODE_IS_DATA;
                        node=new_node;
                        break;
                  }
                  node=node->right;
                  continue;
            }
      }

      /* node will now point to the newly created node */
      switch(se_tree->type){
      case EMEM_TREE_TYPE_RED_BLACK:
            node->u.rb_color=EMEM_TREE_RB_COLOR_RED;
            rb_insert_case1(se_tree, node);
            break;
      }
}

static void *
lookup_or_insert32(emem_tree_t *se_tree, guint32 key, void*(*func)(void*),void* ud, int is_subtree)
{
      emem_tree_node_t *node;

      node=se_tree->tree;

      /* is this the first node ?*/
      if(!node){
            node=se_tree->malloc(sizeof(emem_tree_node_t));
            switch(se_tree->type){
                  case EMEM_TREE_TYPE_RED_BLACK:
                        node->u.rb_color=EMEM_TREE_RB_COLOR_BLACK;
                        break;
            }
            node->parent=NULL;
            node->left=NULL;
            node->right=NULL;
            node->key32=key;
            node->data= func(ud);
            node->u.is_subtree = is_subtree;
            se_tree->tree=node;
            return node->data;
      }

      /* it was not the new root so walk the tree until we find where to
            * insert this new leaf.
            */
      while(1){
            /* this node already exists, so just return the data pointer*/
            if(key==node->key32){
                  return node->data;
            }
            if(key<node->key32) {
                  if(!node->left){
                        /* new node to the left */
                        emem_tree_node_t *new_node;
                        new_node=se_tree->malloc(sizeof(emem_tree_node_t));
                        node->left=new_node;
                        new_node->parent=node;
                        new_node->left=NULL;
                        new_node->right=NULL;
                        new_node->key32=key;
                        new_node->data= func(ud);
                        new_node->u.is_subtree = is_subtree;
                        node=new_node;
                        break;
                  }
                  node=node->left;
                  continue;
            }
            if(key>node->key32) {
                  if(!node->right){
                        /* new node to the right */
                        emem_tree_node_t *new_node;
                        new_node=se_tree->malloc(sizeof(emem_tree_node_t));
                        node->right=new_node;
                        new_node->parent=node;
                        new_node->left=NULL;
                        new_node->right=NULL;
                        new_node->key32=key;
                        new_node->data= func(ud);
                        new_node->u.is_subtree = is_subtree;
                        node=new_node;
                        break;
                  }
                  node=node->right;
                  continue;
            }
      }

      /* node will now point to the newly created node */
      switch(se_tree->type){
            case EMEM_TREE_TYPE_RED_BLACK:
                  node->u.rb_color=EMEM_TREE_RB_COLOR_RED;
                  rb_insert_case1(se_tree, node);
                  break;
      }

      return node->data;
}

/* When the se data is released, this entire tree will dissapear as if it
 * never existed including all metadata associated with the tree.
 */
emem_tree_t *
se_tree_create_non_persistent(int type, const char *name)
{
      emem_tree_t *tree_list;

      tree_list=se_alloc(sizeof(emem_tree_t));
      tree_list->next=NULL;
      tree_list->type=type;
      tree_list->tree=NULL;
      tree_list->name=name;
      tree_list->malloc=se_alloc;

      return tree_list;
}

/* This tree is PErmanent and will never be released
 */
emem_tree_t *
pe_tree_create(int type, const char *name)
{
      emem_tree_t *tree_list;

      tree_list=g_new(emem_tree_t, 1);
      tree_list->next=NULL;
      tree_list->type=type;
      tree_list->tree=NULL;
      tree_list->name=name;
      tree_list->malloc=(void *(*)(size_t)) g_malloc;

      return tree_list;
}

/* create another (sub)tree using the same memory allocation scope
 * as the parent tree.
 */
static emem_tree_t *
emem_tree_create_subtree(emem_tree_t *parent_tree, const char *name)
{
      emem_tree_t *tree_list;

      tree_list=parent_tree->malloc(sizeof(emem_tree_t));
      tree_list->next=NULL;
      tree_list->type=parent_tree->type;
      tree_list->tree=NULL;
      tree_list->name=name;
      tree_list->malloc=parent_tree->malloc;

      return tree_list;
}

static void *
create_sub_tree(void* d)
{
      emem_tree_t *se_tree = d;
      return emem_tree_create_subtree(se_tree, "subtree");
}

/* insert a new node in the tree. if this node matches an already existing node
 * then just replace the data for that node */

void
emem_tree_insert32_array(emem_tree_t *se_tree, emem_tree_key_t *key, void *data)
{
      emem_tree_t *next_tree;

      if((key[0].length<1)||(key[0].length>100)){
            DISSECTOR_ASSERT_NOT_REACHED();
      }
      if((key[0].length==1)&&(key[1].length==0)){
            emem_tree_insert32(se_tree, *key[0].key, data);
            return;
      }

      next_tree=lookup_or_insert32(se_tree, *key[0].key, create_sub_tree, se_tree, EMEM_TREE_NODE_IS_SUBTREE);

      if(key[0].length==1){
            key++;
      } else {
            key[0].length--;
            key[0].key++;
      }
      emem_tree_insert32_array(next_tree, key, data);
}

void *
emem_tree_lookup32_array(emem_tree_t *se_tree, emem_tree_key_t *key)
{
      emem_tree_t *next_tree;

      if(!se_tree || !key) return NULL; /* prevent searching on NULL pointer */

      if((key[0].length<1)||(key[0].length>100)){
            DISSECTOR_ASSERT_NOT_REACHED();
      }
      if((key[0].length==1)&&(key[1].length==0)){
            return emem_tree_lookup32(se_tree, *key[0].key);
      }
      next_tree=emem_tree_lookup32(se_tree, *key[0].key);
      if(!next_tree){
            return NULL;
      }
      if(key[0].length==1){
            key++;
      } else {
            key[0].length--;
            key[0].key++;
      }
      return emem_tree_lookup32_array(next_tree, key);
}

void *
emem_tree_lookup32_array_le(emem_tree_t *se_tree, emem_tree_key_t *key)
{
      emem_tree_t *next_tree;

      if(!se_tree || !key) return NULL; /* prevent searching on NULL pointer */

      if((key[0].length<1)||(key[0].length>100)){
            DISSECTOR_ASSERT_NOT_REACHED();
      }
      if((key[0].length==1)&&(key[1].length==0)){ /* last key in key array */
            return emem_tree_lookup32_le(se_tree, *key[0].key);
      }
      next_tree=emem_tree_lookup32(se_tree, *key[0].key);
      /* key[0].key not found so find le and return */
      if(!next_tree)
            return emem_tree_lookup32_le(se_tree, *key[0].key);

      /* key[0].key found so inc key pointer and try again */
      if(key[0].length==1){
            key++;
      } else {
            key[0].length--;
            key[0].key++;
      }
      return emem_tree_lookup32_array_le(next_tree, key);
}

/* Strings are stored as an array of uint32 containing the string characters
   with 4 characters in each uint32.
   The first byte of the string is stored as the most significant byte.
   If the string is not a multiple of 4 characters in length the last
   uint32 containing the string bytes are padded with 0 bytes.
   After the uint32's containing the string, there is one final terminator
   uint32 with the value 0x00000001
*/
void
emem_tree_insert_string(emem_tree_t* se_tree, const gchar* k, void* v, guint32 flags)
{
      emem_tree_key_t key[2];
      guint32 *aligned=NULL;
      guint32 len = (guint32) strlen(k);
      guint32 divx = (len+3)/4+1;
      guint32 i;
      guint32 tmp;

      aligned = g_malloc(divx * sizeof (guint32));

      /* pack the bytes one one by one into guint32s */
      tmp = 0;
      for (i = 0;i < len;i++) {
            unsigned char ch;

            ch = (unsigned char)k[i];
            if (flags & EMEM_TREE_STRING_NOCASE) {
                  if(isupper(ch)) {
                        ch = tolower(ch);
                  }
            }
            tmp <<= 8;
            tmp |= ch;
            if (i%4 == 3) {
                  aligned[i/4] = tmp;
                  tmp = 0;
            }
      }
      /* add required padding to the last uint32 */
      if (i%4 != 0) {
            while (i%4 != 0) {
                  i++;
                  tmp <<= 8;
            }
            aligned[i/4-1] = tmp;
      }

      /* add the terminator */
      aligned[divx-1] = 0x00000001;

      key[0].length = divx;
      key[0].key = aligned;
      key[1].length = 0;
      key[1].key = NULL;


      emem_tree_insert32_array(se_tree, key, v);
      g_free(aligned);
}

void *
emem_tree_lookup_string(emem_tree_t* se_tree, const gchar* k, guint32 flags)
{
      emem_tree_key_t key[2];
      guint32 *aligned=NULL;
      guint32 len = (guint) strlen(k);
      guint32 divx = (len+3)/4+1;
      guint32 i;
      guint32 tmp;
      void *ret;

      aligned = g_malloc(divx * sizeof (guint32));

      /* pack the bytes one one by one into guint32s */
      tmp = 0;
      for (i = 0;i < len;i++) {
            unsigned char ch;

            ch = (unsigned char)k[i];
            if (flags & EMEM_TREE_STRING_NOCASE) {
                  if(isupper(ch)) {
                        ch = tolower(ch);
                  }
            }
            tmp <<= 8;
            tmp |= ch;
            if (i%4 == 3) {
                  aligned[i/4] = tmp;
                  tmp = 0;
            }
      }
      /* add required padding to the last uint32 */
      if (i%4 != 0) {
            while (i%4 != 0) {
                  i++;
                  tmp <<= 8;
            }
            aligned[i/4-1] = tmp;
      }

      /* add the terminator */
      aligned[divx-1] = 0x00000001;

      key[0].length = divx;
      key[0].key = aligned;
      key[1].length = 0;
      key[1].key = NULL;


      ret = emem_tree_lookup32_array(se_tree, key);
      g_free(aligned);
      return ret;
}

static gboolean
emem_tree_foreach_nodes(emem_tree_node_t* node, tree_foreach_func callback, void *user_data)
{
      gboolean stop_traverse = FALSE;

      if (!node)
            return FALSE;

      if(node->left) {
            stop_traverse = emem_tree_foreach_nodes(node->left, callback, user_data);
            if (stop_traverse) {
                  return TRUE;
            }
      }

      if (node->u.is_subtree == EMEM_TREE_NODE_IS_SUBTREE) {
            stop_traverse = emem_tree_foreach(node->data, callback, user_data);
      } else {
            stop_traverse = callback(node->data, user_data);
      }

      if (stop_traverse) {
            return TRUE;
      }

      if(node->right) {
            stop_traverse = emem_tree_foreach_nodes(node->right, callback, user_data);
            if (stop_traverse) {
                  return TRUE;
            }
      }

      return FALSE;
}

gboolean
emem_tree_foreach(emem_tree_t* emem_tree, tree_foreach_func callback, void *user_data)
{
      if (!emem_tree)
            return FALSE;

      if(!emem_tree->tree)
            return FALSE;

      return emem_tree_foreach_nodes(emem_tree->tree, callback, user_data);
}


static void
emem_tree_print_nodes(emem_tree_node_t* node, int level)
{
      int i;

      if (!node)
            return;

      for(i=0;i<level;i++){
            printf("    ");
      }

      printf("NODE:%p parent:%p left:0x%p right:%px key:%d data:%p\n",
            (void *)node,(void *)(node->parent),(void *)(node->left),(void *)(node->right),
            (node->key32),node->data);
      if(node->left)
            emem_tree_print_nodes(node->left, level+1);
      if(node->right)
            emem_tree_print_nodes(node->right, level+1);
}
void
emem_print_tree(emem_tree_t* emem_tree)
{
      if (!emem_tree)
            return;

      printf("EMEM tree type:%d name:%s tree:%p\n",emem_tree->type,emem_tree->name,(void *)(emem_tree->tree));
      if(emem_tree->tree)
            emem_tree_print_nodes(emem_tree->tree, 0);
}

/*
 * String buffers
 */

/*
 * Presumably we're using these routines for building strings for the tree.
 * Use ITEM_LABEL_LENGTH as the basis for our default lengths.
 */

#define DEFAULT_STRBUF_LEN (ITEM_LABEL_LENGTH / 10)
#define MAX_STRBUF_LEN 65536

static gsize
next_size(gsize cur_alloc_len, gsize wanted_alloc_len, gsize max_alloc_len)
{
      if (max_alloc_len < 1 || max_alloc_len > MAX_STRBUF_LEN) {
            max_alloc_len = MAX_STRBUF_LEN;
      }

      if (cur_alloc_len < 1) {
            cur_alloc_len = DEFAULT_STRBUF_LEN;
      }

      while (cur_alloc_len < wanted_alloc_len) {
            cur_alloc_len *= 2;
      }

      return cur_alloc_len < max_alloc_len ? cur_alloc_len : max_alloc_len;
}

static void
ep_strbuf_grow(emem_strbuf_t *strbuf, gsize wanted_alloc_len)
{
      gsize new_alloc_len;
      gchar *new_str;

      if (!strbuf || (wanted_alloc_len <= strbuf->alloc_len) || (strbuf->alloc_len >= strbuf->max_alloc_len)) {
            return;
      }

      new_alloc_len = next_size(strbuf->alloc_len, wanted_alloc_len, strbuf->max_alloc_len);
      new_str = ep_alloc(new_alloc_len);
      g_strlcpy(new_str, strbuf->str, new_alloc_len);

      strbuf->alloc_len = new_alloc_len;
      strbuf->str = new_str;
}

emem_strbuf_t *
ep_strbuf_sized_new(gsize alloc_len, gsize max_alloc_len)
{
      emem_strbuf_t *strbuf;

      strbuf = ep_alloc(sizeof(emem_strbuf_t));

      if ((max_alloc_len == 0) || (max_alloc_len > MAX_STRBUF_LEN))
            max_alloc_len = MAX_STRBUF_LEN;
      if (alloc_len == 0)
            alloc_len = 1;
      else if (alloc_len > max_alloc_len)
            alloc_len = max_alloc_len;

      strbuf->str = ep_alloc(alloc_len);
      strbuf->str[0] = '\0';

      strbuf->len = 0;
      strbuf->alloc_len = alloc_len;
      strbuf->max_alloc_len = max_alloc_len;

      return strbuf;
}

emem_strbuf_t *
ep_strbuf_new(const gchar *init)
{
      emem_strbuf_t *strbuf;

      strbuf = ep_strbuf_sized_new(next_size(0, init?strlen(init):0, 0), 0);
      if (init) {
            gsize full_len;
            full_len = g_strlcpy(strbuf->str, init, strbuf->alloc_len);
            strbuf->len = MIN(full_len, strbuf->alloc_len-1);
      }

      return strbuf;
}

emem_strbuf_t *
ep_strbuf_new_label(const gchar *init)
{
      emem_strbuf_t *strbuf;
      gsize full_len;

      /* Be optimistic: Allocate default size strbuf string and only      */
        /*  request an increase if needed.                                  */
        /* XXX: Is it reasonable to assume that much of the usage of        */
        /*  ep_strbuf_new_label will have  init==NULL or                    */
        /*   strlen(init) < DEFAULT_STRBUF_LEN) ???                         */
      strbuf = ep_strbuf_sized_new(DEFAULT_STRBUF_LEN, ITEM_LABEL_LENGTH);

      if (!init)
            return strbuf;

      /* full_len does not count the trailing '\0'.                       */
      full_len = g_strlcpy(strbuf->str, init, strbuf->alloc_len);
      if (full_len < strbuf->alloc_len) {
            strbuf->len += full_len;
      } else {
            strbuf = ep_strbuf_sized_new(full_len+1, ITEM_LABEL_LENGTH);
            full_len = g_strlcpy(strbuf->str, init, strbuf->alloc_len);
            strbuf->len = MIN(full_len, strbuf->alloc_len-1);
      }

      return strbuf;
}

emem_strbuf_t *
ep_strbuf_append(emem_strbuf_t *strbuf, const gchar *str)
{
      gsize add_len, full_len;

      if (!strbuf || !str || str[0] == '\0') {
            return strbuf;
      }

      /* Be optimistic; try the g_strlcpy first & see if enough room.                 */
      /* Note: full_len doesn't count the trailing '\0'; add_len does allow for same  */
      add_len = strbuf->alloc_len - strbuf->len;
      full_len = g_strlcpy(&strbuf->str[strbuf->len], str, add_len);
      if (full_len < add_len) {
            strbuf->len += full_len;
      } else {
            strbuf->str[strbuf->len] = '\0'; /* end string at original length again */
            ep_strbuf_grow(strbuf, strbuf->len + full_len + 1);
            add_len = strbuf->alloc_len - strbuf->len;
            full_len = g_strlcpy(&strbuf->str[strbuf->len], str, add_len);
            strbuf->len += MIN(add_len-1, full_len);
      }

      return strbuf;
}

void
ep_strbuf_append_vprintf(emem_strbuf_t *strbuf, const gchar *format, va_list ap)
{
      va_list ap2;
      gsize add_len, full_len;

      G_VA_COPY(ap2, ap);

      /* Be optimistic; try the g_vsnprintf first & see if enough room.               */
      /* Note: full_len doesn't count the trailing '\0'; add_len does allow for same. */
      add_len = strbuf->alloc_len - strbuf->len;
      full_len = g_vsnprintf(&strbuf->str[strbuf->len], (gulong) add_len, format, ap);
      if (full_len < add_len) {
            strbuf->len += full_len;
      } else {
            strbuf->str[strbuf->len] = '\0'; /* end string at original length again */
            ep_strbuf_grow(strbuf, strbuf->len + full_len + 1);
            add_len = strbuf->alloc_len - strbuf->len;
            full_len = g_vsnprintf(&strbuf->str[strbuf->len], (gulong) add_len, format, ap2);
            strbuf->len += MIN(add_len-1, full_len);
      }

      va_end(ap2);
}

void
ep_strbuf_append_printf(emem_strbuf_t *strbuf, const gchar *format, ...)
{
      va_list ap;

      va_start(ap, format);
      ep_strbuf_append_vprintf(strbuf, format, ap);
      va_end(ap);
}

void
ep_strbuf_printf(emem_strbuf_t *strbuf, const gchar *format, ...)
{
      va_list ap;
      if (!strbuf) {
            return;
      }

      strbuf->len = 0;

      va_start(ap, format);
      ep_strbuf_append_vprintf(strbuf, format, ap);
      va_end(ap);
}

emem_strbuf_t *
ep_strbuf_append_c(emem_strbuf_t *strbuf, const gchar c)
{
      if (!strbuf) {
            return strbuf;
      }

      /* +1 for the new character & +1 for the trailing '\0'. */
      if (strbuf->alloc_len < strbuf->len + 1 + 1) {
            ep_strbuf_grow(strbuf, strbuf->len + 1 + 1);
      }
      if (strbuf->alloc_len >= strbuf->len + 1 + 1) {
            strbuf->str[strbuf->len] = c;
            strbuf->len++;
            strbuf->str[strbuf->len] = '\0';
      }

      return strbuf;
}

emem_strbuf_t *
ep_strbuf_truncate(emem_strbuf_t *strbuf, gsize len)
{
      if (!strbuf || len >= strbuf->len) {
            return strbuf;
      }

      strbuf->str[len] = '\0';
      strbuf->len = len;

      return strbuf;
}

/*
 * Editor modelines
 *
 * Local Variables:
 * c-basic-offset: 8
 * tab-width: 8
 * indent-tabs-mode: t
 * End:
 *
 * ex: set shiftwidth=8 tabstop=8 noexpandtab
 * :indentSize=8:tabSize=8:noTabs=false:
 */

Generated by  Doxygen 1.6.0   Back to index