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Sourcecode: samba-doc-ja version File versions

parser.c

#include "parser.h"

/*******************************************************************
 Attempt, if needed, to grow a data buffer.
 Also depends on the data stream mode (io).
 ********************************************************************/

BOOL io_grow(io_struct *ps, uint32 extra_space)
{
      uint32 new_size;
      char *new_data;

      ps->grow_size = MAX(ps->grow_size, ps->data_offset + extra_space);

      if(ps->data_offset + extra_space <= ps->buffer_size)
            return True;

      /*
       * We cannot grow the buffer if we're not reading
       * into the io_struct, or if we don't own the memory.
       */

      if(UNMARSHALLING(ps) || !ps->is_dynamic) {
            DEBUG(0,("io_grow: Buffer overflow - unable to expand buffer by %u bytes.\n",
                        (unsigned int)extra_space));
            return False;
      }
      
      /*
       * Decide how much extra space we really need.
       */

      extra_space -= (ps->buffer_size - ps->data_offset);
      if(ps->buffer_size == 0) {
            new_size = extra_space;

            if((new_data = (char *)malloc(new_size)) == NULL) {
                  DEBUG(0,("io_grow: Malloc failure for size %u.\n", (unsigned int)new_size));
                  return False;
            }
            memset(new_data, '\0', new_size );
      } else {
            /*
             * If the current buffer size is bigger than the space needed, just 
             * double it, else add extra_space.
             */
            new_size = MAX(ps->buffer_size*2, ps->buffer_size + extra_space);       

            if ((new_data = Realloc(ps->data_p, new_size)) == NULL) {
                  DEBUG(0,("io_grow: Realloc failure for size %u.\n",
                        (unsigned int)new_size));
                  return False;
            }
      }
      ps->buffer_size = new_size;
      ps->data_p = new_data;

      return True;
}


/*******************************************************************
 Ensure we can read/write to a given offset.
 ********************************************************************/

char *io_mem_get(io_struct *ps, uint32 extra_size)
{
      if(UNMARSHALLING(ps)) {
            /*
             * If reading, ensure that we can read the requested size item.
             */
            if (ps->data_offset + extra_size > ps->buffer_size) {
                  DEBUG(0,("io_mem_get: reading data of size %u would overrun buffer.\n",
                              (unsigned int)extra_size ));
                  return NULL;
            }
      } else {
            /*
             * Writing - grow the buffer if needed.
             */
            if(!io_grow(ps, extra_size))
                  return False;
      }
      return &ps->data_p[ps->data_offset];
}

/*******************************************************************
 Initialise a parse structure - malloc the data if requested.
 ********************************************************************/

BOOL io_init(io_struct *ps, uint32 size, BOOL io)
{
      ZERO_STRUCTP(ps);
      ps->io = io;
      ps->bigendian_data = False;
      ps->is_dynamic = False;
      ps->data_offset = 0;
      ps->buffer_size = 0;
      ps->data_p = NULL;

      if (size != 0) {
            ps->buffer_size = size;
            if((ps->data_p = (char *)malloc((size_t)size)) == NULL) {
                  DEBUG(0,("io_init: malloc fail for %u bytes.\n", (unsigned int)size));
                  return False;
            }
            ps->is_dynamic = True; /* We own this memory. */
      }

      return True;
}

/*******************************************************************
 debug output for parsing info.

 XXXX side-effect of this function is to increase the debug depth XXXX

 ********************************************************************/
void io_debug(io_struct *ps, int depth, char *desc, char *fn_name)
{
      DEBUG(5+depth, ("%s%06x %s %s\n", tab_depth(depth), ps->data_offset, fn_name, desc));
}

/*******************************************************************
 Align a the data_len to a multiple of align bytes - filling with
 zeros.
 ********************************************************************/

BOOL io_align2(io_struct *ps, int offset)
{
      uint32 mod = (ps->data_offset + offset) & (2-1);

      if (mod != 0) {
            uint32 extra_space = (2 - mod);
            if(!io_grow(ps, extra_space))
                  return False;
            memset(&ps->data_p[ps->data_offset], '\0', (size_t)extra_space);
            ps->data_offset += extra_space;
      }

      return True;
}

BOOL io_align4(io_struct *ps, int offset)
{
      uint32 mod = (ps->data_offset + offset) & (4-1);

      if (mod != 0) {
            uint32 extra_space = (4 - mod);
            if(!io_grow(ps, extra_space))
                  return False;
            memset(&ps->data_p[ps->data_offset], '\0', (size_t)extra_space);
            ps->data_offset += extra_space;
      }

      return True;
}

/*******************************************************************
 Align a the data_len to a multiple of align bytes - filling with
 zeros.
 ********************************************************************/

BOOL io_align(io_struct *ps, int align)
{
      uint32 mod;

      if (!ps->autoalign) return True;

      mod = ps->data_offset & (align-1);

      if (align != 0 && mod != 0) {
            uint32 extra_space = (align - mod);
            if(!io_grow(ps, extra_space))
                  return False;
            memset(&ps->data_p[ps->data_offset], '\0', (size_t)extra_space);
            ps->data_offset += extra_space;
      }

      return True;
}


/*******************************************************************
 read from a socket into memory.
 ********************************************************************/
BOOL io_read(io_struct *ps, int fd, size_t len, int timeout)
{
      BOOL ok;
      size_t prev_size = ps->buffer_size;
      if (!io_grow(ps, len))
      {
            return False;
      }

      if (timeout > 0)
      {
            ok = (read(fd, &ps->data_p[prev_size], len) == len);
      }
      else 
      {
            ok = (read(fd, &ps->data_p[prev_size], len) == len);
      }
      return ok;
}


/*******************************************************************
 do IO on a uint32.
 ********************************************************************/
BOOL io_uint32(char *name, io_struct *ps, int depth, uint32 *data32, unsigned flags)
{
      char *q;

      if (!(flags & PARSE_SCALARS)) return True;

      if (!io_align(ps, 4)) return False;

      q = io_mem_get(ps, sizeof(uint32));
      if (q == NULL) return False;

      DBG_RW_IVAL(name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, *data32)
      ps->data_offset += sizeof(uint32);

      return True;
}

/*******************************************************************
 do IO on a uint16.
 ********************************************************************/
BOOL io_uint16(char *name, io_struct *ps, int depth, uint16 *data16, unsigned flags)
{
      char *q;

      if (!(flags & PARSE_SCALARS)) return True;

      if (!io_align(ps, 2)) return False;

      q = io_mem_get(ps, sizeof(uint16));
      if (q == NULL) return False;

      DBG_RW_SVAL(name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, *data16)
      ps->data_offset += sizeof(uint16);

      return True;
}

/*******************************************************************
 do IO on a uint8.
 ********************************************************************/
BOOL io_uint8(char *name, io_struct *ps, int depth, uint8 *data8, unsigned flags)
{
      char *q;

      if (!(flags & PARSE_SCALARS)) return True;

      q = io_mem_get(ps, sizeof(uint8));
      if (q == NULL) return False;

      DBG_RW_IVAL(name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, *data8)
      ps->data_offset += sizeof(uint8);

      return True;
}

/*******************************************************************
 do IO on a pointer
 ********************************************************************/
BOOL io_pointer(char *desc, io_struct *ps, int depth, void **p, unsigned flags)
{
      uint32 v;

      if (!(flags & PARSE_SCALARS)) return True;

      v = (*p) ? 0xdeadbeef : 0;
      if (!io_uint32(desc, ps, depth, &v, flags)) return False;
      *p = (void *) (v ? 0xdeadbeef : 0);
      return True;
}

/*******************************************************************
 Stream a null-terminated string.  
 ********************************************************************/
BOOL io_SMBSTR(char *name, io_struct *ps, int depth, char **str, unsigned flags)
{
      char *q;
      uint8 *start;
      int i;
      size_t len;
      int start_offset = ps->data_offset;

      if (!(flags & PARSE_SCALARS)) return True;
      
      if (UNMARSHALLING(ps)) {
            *str = io_mem_get(ps, 0);
            if (*str == NULL)
                  return False;
            len = strlen(*str);
            ps->data_offset += len + 1;
      }
      else
      {
            len = strlen(*str)+1;
            start = (uint8*)q;

            for(i = 0; i < len; i++) {
                  q = io_mem_get(ps, 1);
                  if (q == NULL)
                        return False;

                  RW_CVAL(ps->io, q, (*str)[i],0);
                  ps->data_offset++;
            }
      }

      DEBUG(5,("%s%04x %s: %s\n", tab_depth(depth),
                        start_offset, name, *str));
      return True;
}

/******************************************************************
 do IO on a byte array
 ********************************************************************/
BOOL io_uint8s(char *name, io_struct *ps, int depth, uint8 **data8s, int len, unsigned flags)
{
      char *q;
      size_t num_bytes = len * sizeof(uint8);

      if (!(flags & PARSE_SCALARS)) return True;

      q = io_mem_get(ps, num_bytes);
      if (q == NULL) return False;

      if (MARSHALLING(ps))
      {
            DBG_RW_PCVAL(True, name, depth, ps->data_offset, ps->io, q, *data8s, len)
      }
      else
      {
            *data8s = q;
            dump_data(depth+5, *data8s, num_bytes);
      }
      ps->data_offset += num_bytes;

      return True;
}
/******************************************************************
 do IO on a fixed-size byte array
 ********************************************************************/
BOOL io_uint8s_fixed(char *name, io_struct *ps, int depth, uint8 *data8s, int len, unsigned flags)
{
      char *q;
      size_t num_bytes = len * sizeof(uint8);

      if (!(flags & PARSE_SCALARS)) return True;

      q = io_mem_get(ps, num_bytes);
      if (q == NULL) return False;

      DBG_RW_PCVAL(True, name, depth, ps->data_offset, ps->io, q, data8s, len)
      ps->data_offset += num_bytes;

      return True;
}


/******************************************************************
 do IO on an io (eh?? :)
 ********************************************************************/
BOOL io_io_struct(char *name, io_struct *ps, int depth, io_struct *io, unsigned flags)
{
      char *q;
      uint16 len;

      if (!(flags & PARSE_SCALARS)) return True;

      q = io_mem_get(ps, sizeof(uint16));
      if (q == NULL) return False;

      /* length first */
      if (MARSHALLING(ps))
      {
            len = io->data_offset;
      }
      if (!io_uint16("len", ps, depth+1, &len, flags))
      {
            return False;
      }
      if (UNMARSHALLING(ps))
      {
            if (!io_init(io, len, UNMARSHALL))
            {
                  return False;
            }
      }

      /* now data */
      q = io_mem_get(ps, len * sizeof(uint8));
      if (q == NULL) return False;

      if (MARSHALLING(ps))
      {
            DBG_RW_PCVAL(False, name, depth+1, ps->data_offset, ps->io, q, io->data_p, len)
      }
      else
      {
            io->data_p = q;
            dump_data(depth+5, q, len);
      }
      ps->data_offset += len;

      return True;
}

/******************************************************************
 do IO on a unicode array
 ********************************************************************/
BOOL io_wstring(char *name, io_struct *ps, int depth, uint16 *data16s, int len, unsigned flags)
{
      char *q;

      if (!(flags & PARSE_SCALARS)) return True;

      if (!io_align(ps, 2)) return False;

      q = io_mem_get(ps, len * sizeof(uint16));
      if (q == NULL) return False;

      DBG_RW_PSVAL(True, name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, data16s, len)
      ps->data_offset += (len * sizeof(uint16));

      return True;
}


/******************************************************************
allocate some memory for a parse structure
 ********************************************************************/
void io_free(io_struct *ps)
{
      if (ps->is_dynamic && ps->data_p)
      {
            free(ps->data_p);
            ps->data_p = NULL;
      }
}

/******************************************************************
allocate some memory for a parse structure
 ********************************************************************/
BOOL io_alloc(char *name, io_struct *ps, void **ptr, unsigned size)
{
      (*ptr) = (void *)malloc(size);
      if (*ptr) return True;
      return False;
}

/******************************************************************
realloc some memory for a parse structure
 ********************************************************************/
BOOL io_realloc(char *name, io_struct *ps, void **ptr, unsigned size)
{
      (*ptr) = (void *)Realloc(*ptr, size);
      if (*ptr) return True;
      return False;
}


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