cpack.c File Reference

#include <include.h>
#include <tcpdump-stdinc.h>
#include "cpack.h"
#include "extract.h"

Include dependency graph for cpack.c:

Go to the source code of this file.

Functions
static u_int8_t *	cpack_next_boundary (u_int8_t *buf, u_int8_t *p, size_t alignment)
static u_int8_t *	cpack_align_and_reserve (struct cpack_state *cs, size_t wordsize)
int	cpack_init (struct cpack_state *cs, u_int8_t *buf, size_t buflen)
int	cpack_uint64 (struct cpack_state *cs, u_int64_t *u)
int	cpack_uint32 (struct cpack_state *cs, u_int32_t *u)
int	cpack_uint16 (struct cpack_state *cs, u_int16_t *u)
int	cpack_uint8 (struct cpack_state *cs, u_int8_t *u)

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Function Documentation

static u_int8_t* cpack_next_boundary	(	u_int8_t *	buf,
		u_int8_t *	p,
		size_t	alignment
	)			[static]

Definition at line 41 of file cpack.c.

Referenced by cpack_align_and_reserve().

{
  size_t misalignment = (size_t)(p - buf) % alignment;

  if (misalignment == 0)
    return p;

  return p + (alignment - misalignment);
}

static u_int8_t* cpack_align_and_reserve	(	struct cpack_state *	cs,
		size_t	wordsize
	)			[static]

Definition at line 56 of file cpack.c.

References cpack_state::c_buf, cpack_state::c_len, cpack_state::c_next, and cpack_next_boundary().

Referenced by cpack_uint16(), cpack_uint32(), and cpack_uint64().

{
  u_int8_t *next;

  /* Ensure alignment. */
  next = cpack_next_boundary(cs->c_buf, cs->c_next, wordsize);

  /* Too little space for wordsize bytes? */
  if (next - cs->c_buf + wordsize > cs->c_len)
    return NULL;

  return next;
}

int cpack_init	(	struct cpack_state *	cs,
		u_int8_t *	buf,
		size_t	buflen
	)

Definition at line 71 of file cpack.c.

References cpack_state::c_buf, cpack_state::c_len, and cpack_state::c_next.

Referenced by FillRadioData().

{
  memset(cs, 0, sizeof(*cs));

  cs->c_buf = buf;
  cs->c_len = buflen;
  cs->c_next = cs->c_buf;

  return 0;
}

int cpack_uint64	(	struct cpack_state *	cs,
		u_int64_t *	u
	)

Definition at line 84 of file cpack.c.

References cpack_state::c_next, cpack_align_and_reserve(), and EXTRACT_LE_64BITS.

Referenced by extract_radiotap_field().

{
  u_int8_t *next;

  if ((next = cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
    return -1;

  *u = EXTRACT_LE_64BITS(next);

  /* Move pointer past the u_int64_t. */
  cs->c_next = next + sizeof(*u);
  return 0;
}

int cpack_uint32	(	struct cpack_state *	cs,
		u_int32_t *	u
	)

Definition at line 100 of file cpack.c.

References cpack_state::c_next, cpack_align_and_reserve(), and EXTRACT_LE_32BITS.

{
  u_int8_t *next;

  if ((next = cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
    return -1;

  *u = EXTRACT_LE_32BITS(next);

  /* Move pointer past the u_int32_t. */
  cs->c_next = next + sizeof(*u);
  return 0;
}

int cpack_uint16	(	struct cpack_state *	cs,
		u_int16_t *	u
	)

Definition at line 116 of file cpack.c.

References cpack_state::c_next, cpack_align_and_reserve(), and EXTRACT_LE_16BITS.

Referenced by extract_radiotap_field().

{
  u_int8_t *next;

  if ((next = cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
    return -1;

  *u = EXTRACT_LE_16BITS(next);

  /* Move pointer past the u_int16_t. */
  cs->c_next = next + sizeof(*u);
  return 0;
}

int cpack_uint8	(	struct cpack_state *	cs,
		u_int8_t *	u
	)

Definition at line 132 of file cpack.c.

References cpack_state::c_buf, cpack_state::c_len, and cpack_state::c_next.

Referenced by extract_radiotap_field().

{
  /* No space left? */
  if ((size_t)(cs->c_next - cs->c_buf) >= cs->c_len)
    return -1;

  *u = *cs->c_next;

  /* Move pointer past the u_int8_t. */
  cs->c_next++;
  return 0;
}