msg_parser_util.c

this is simple sip stack.

      if (strncasecmp(maybe, param, n) == 0) {
	if (maybe[n] == '=' || maybe[n] == 0) {
	  params[i] = param;	
	  return 1;
	}
      }
    }
  }

  /* Not found on list */
  return msg_params_add(home, inout_params, param);
}

/** Remove a parameter from a list. 
 *
 * @retval 1 if parameter was removed
 * @retval 0 if parameter was not found
 * @retval -1 upon an error
 */
int msg_params_remove(msg_param_t *params, msg_param_t param)
{
  int i, n;

  if (!params || !param || !param[0])
    return -1;

  n = strcspn(param, "=");
  assert(n > 0);

  for (i = 0; params[i]; i++) {
    msg_param_t maybe = params[i];

    if (strncasecmp(maybe, param, n) == 0) {
      if (maybe[n] == '=' || maybe[n] == 0) {
	/* Remove */
	do {
	  params[i] = params[i + 1];
	} while (params[i++]);
	return 1;
      }
    }
  }

  return 0;
}

/** Calculate number of parameters in a parameter list */
size_t msg_params_length(char const * const * params)
{
  size_t len;

  if (!params)
    return 0;

  for (len = 0; params[len]; len++)
    ;

  return len;
}


/**
 * Add a parameter to a list.
 *
 * Add a parameter to the list; the list must have been created by @c
 * msg_params_d() or by @c msg_params_dup() (or it may contain only @c
 * NULL).
 *
 * @note This function does not duplicate @p param.
 *
 * @param home      memory home
 * @param inout_params   pointer to pointer to parameter list
 * @param param     parameter to be added
 *
 * @retval 0 if parameter was added 
 * @retval -1 upon an error
 */
int msg_params_add(su_home_t *home,
		   msg_param_t **inout_params,
		   msg_param_t param)
{
  int n, m_before, m_after;
  msg_param_t *p = *inout_params;  

  if (param == NULL)
    return -1;

  /* Count number of parameters */
  for (n = 0; p && p[n]; n++)
    ;

  m_before = MSG_PARAMS_NUM(n + 1);
  m_after =  MSG_PARAMS_NUM(n + 2);
  
  if (m_before != m_after || !p) {
    p = su_alloc(home, m_after * sizeof(*p)); 
    assert(p); if (!p) return -1;
    if (n)
      memcpy(p, *inout_params, n * sizeof(*p));
    *inout_params = p;
  }

  p[n] = param;
  p[n + 1] = NULL;

  return 0;
}

static 
int msg_param_prune(msg_param_t const d[], msg_param_t p, unsigned prune)
{
  int i, nlen;

  if (prune == 1)
    nlen = strcspn(p, "=");
  else
    nlen = 0;

  for (i = 0; d[i]; i++) {
    if ((prune == 1 && 
	 strncasecmp(p, d[i], nlen) == 0 
	 && (d[i][nlen] == '=' || d[i][nlen] == '\0'))
	|| 
	(prune == 2 && strcasecmp(p, d[i]) == 0)
	||
	(prune == 3 && strcmp(p, d[i]) == 0))
      return 1;
  }

  return 0;
}

/**Join two parameter lists.
 *
 * The function @c msg_params_join() joins two parameter lists; the
 * first list must have been created by @c msg_params_d() or by @c
 * msg_params_dup() (or it may contain only @c NULL).
 *
 * @param home    memory home
 * @param dst     pointer to pointer to destination parameter list
 * @param src     source list
 * @param prune   prune duplicates 
 * @param dup     duplicate parameters in src list
 *
 * @par Pruning 
 * <table>
 * <tr><td>0<td>do not prune</tr>
 * <tr><td>1<td>prune parameters with identical names</tr>
 * <tr><td>2<td>case-insensitive values</tr>
 * <tr><td>3<td>case-sensitive values</tr>
 * </table>
 *
 * @return
 * The function @c msg_params_join() returns 0 if successful, or a negative
 * value upon an error.
 */
int msg_params_join(su_home_t *home,
		    msg_param_t **dst,
		    msg_param_t const *src,
		    unsigned prune,
		    int dup)
{
  int n, m, n_before, n_after, pruned, total = 0;
  msg_param_t *d = *dst;  

  if (prune > 3)
    return -1;

  if (src == NULL || *src == NULL)
    return 0;

  /* Count number of parameters */
  for (n = 0; d && d[n]; n++)
    ;

  n_before = MSG_PARAMS_NUM(n + 1);

  for (m = 0, pruned = 0; src[m]; m++) {
    if (n > 0 && prune > 0 && msg_param_prune(d, src[m], prune)) {
      pruned++;
      if (prune > 1)
	continue;
    }
    if (dup)
      total += strlen(src[m]) + 1;
  }

  n_after = MSG_PARAMS_NUM(n + m - pruned + 1);
  
  if (n_before != n_after || !d) {
    d = su_alloc(home, n_after * sizeof(*d)); 
    assert(d); if (!d) return -1;
    if (n)
      memcpy(d, *dst, n * sizeof(*d));
    *dst = d;
  }

  for (m = 0; src[m]; m++) {
    if (pruned && msg_param_prune(d, src[m], prune)) {
      pruned--;
      if (prune > 1)
	continue;
    }

    if (dup)
      d[n++] = su_strdup(home, src[m]);	/* XXX */
    else
      d[n++] = src[m];
  }  

  d[n] = NULL;

  return 0;
}

/**Compare parameter lists.
 * 
 * Compares parameter lists.
 *
 * @param a pointer to a parameter list
 * @param b pointer to a parameter list
 *
 * @retval an integer less than zero if @a is less than @a b
 * @retval an integer zero if @a match with @a b
 * @retval an integer greater than zero if @a is greater than @a b
 */
int msg_params_cmp(char const * const a[], char const * const b[])
{
  int c;
  int nlen;

  if (a == NULL || b == NULL)
    return (a != NULL) - (b != NULL);

  for (;;) {
    if (*a == NULL || *b == NULL)
      return (*a != NULL) - (*b != NULL);
    nlen = strcspn(*a, "=");
    if ((c = strncasecmp(*a, *b, nlen)))
      return c;
    if ((c = strcmp(*a + nlen, *b + nlen)))
      return c;
    a++, b++;
  }
}


/** Unquote string 
 *
 * Duplicates the string @a q in unquoted form.
 */
char *msg_unquote_dup(su_home_t *home, char const *q)
{
  char *d;
  int total, n, m;

  /* First, easy case */
  if (q[0] == '"')
    q++;
  n = strcspn(q, "\"\\");
  if (q[n] == '\0' || q[n] == '"')
    return su_strndup(home, q, n);

  /* Hairy case - backslash-escaped chars */
  total = n;
  for (;;) {
    if (q[n] == '\0' || q[n] == '"' || q[n + 1] == '\0')
      break;
    m = strcspn(q + n + 2, "\"\\");
    total += m + 1;
    n += m + 2; 
  }

  if (!(d = su_alloc(home, total + 1)))
    return NULL;

  for (n = 0;;) {
    m = strcspn(q, "\"\\");
    memcpy(d + n, q, m); 
    n += m, q += m;
    if (q[0] == '\0' || q[0] == '"' || q[1] == '\0')
      break;
    d[n++] = q[1]; 
    q += 2;
  }
  assert(total == n);
  d[n] = '\0';
  
  return d;
}

/** Unquote string */
char *msg_unquote(char *dst, char const *s)
{
  int copy = dst != NULL;
  char *d = dst;

  if (*s++ != '"')
    return NULL;

  for (;;) {
    int n = strcspn(s, "\"\\");
    if (copy)
      memmove(d, s, n);
    s += n;
    d += n;

    if (*s == '\0')
      return NULL;
    else if (*s == '"') {
      if (copy) *d = '\0';
      return dst;
    }
    else {
      /* Copy quoted char */
      if ((copy ? (*d++ = *++s) : *++s) == '\0')
	return NULL;
      s++;
    }
  }
}

/** Quote string */
int msg_unquoted_e(char *b, int bsiz, char const *s)
{
  char *begin = b;
  char *end = b + bsiz;

  if (b && b + 1 < end)
    *b = '"';
  b++;
  
  for (;*s;) {
    int n = strcspn(s, "\"\\");

    if (n == 0) {
      if (b && b + 2 < end)
	b[0] = '\\', b[1] = s[0];
      b += 2;
      s++;
    }
    else {
      if (b && b + n < end)
	memcpy(b, s, n);
      b += n;
      s += n;
    }
  }

  if (b && b + 1 < end)
    *b = '"';
  b++;

  return b - begin;
}


/** Calculate a simple hash over a string. */
unsigned long msg_hash_string(char const *id)
{
  unsigned long hash = 0;

  if (id)
    for (; *id; id++) {
      hash += (unsigned)*id;
      hash *= 38501U;
    }
  else
    hash *= 38501U;

  if (hash == 0)
    hash = (unsigned long)-1;
  
  return hash;
}


/** Calculate the size of a duplicate of a header structure. */
int msg_header_size(msg_header_t const *h)
{
  if (h == NULL || h == MSG_HEADER_NONE)
    return 0;
  else
    return h->sh_class->hc_dxtra(h, h->sh_class->hc_size);
}


/** Encode a message to the buffer. 
 *
 * The function msg_encode_e encodes a message to a given buffer.
 * It returns the length of the message to be encoded, even if the
 * buffer is too small (just like snprintf() is supposed to do).
 *
 * @param b        buffer (may be NULL)
 * @param size     size of buffer 
 * @param mo       public message structure (#sip_t, #http_t)
 * @param flags    see #
 */
int msg_object_e(char b[], int size, msg_pub_t const *mo, int flags)
{
  int rv = 0, n;
  msg_header_t const *h;

  if (mo->msg_request)
    h = mo->msg_request;
  else
    h = mo->msg_status;

  for (; h; h = h->sh_succ) {
    n = msg_header_e(b, size, h, flags);
    if ((unsigned)n < (unsigned)size)
      b += n, size -= n;
    else
      b = NULL, size = 0;
    rv += n;
  }

  return rv;
}

/** Encode header contents. */
int msg_header_field_e(char b[], int bsiz, msg_header_t const *h, int flags)
{
  assert(h); assert(h->sh_class); 

  return h->sh_class->hc_print(b, bsiz, h, flags);
}

/** Get offset of header @a h from structure @a mo. */
msg_header_t **
msg_header_offset(msg_t const *msg, msg_pub_t const *mo, msg_header_t const *h)
{
  if (h == NULL || h->sh_class == NULL) 
    return NULL;

  return msg_hclass_offset(msg->m_class, mo, h->sh_class);
}

/**Get a header from the public message structure.
 *
 * Gets a pointer to header from a message structure.
 *
 * @param pub public message structure from which header is obtained
 * @param hc  header class
 */
msg_header_t *
msg_header_access(msg_pub_t const *pub, msg_hclass_t *hc)
{
  msg_header_t * const * hh;

  if (pub == NULL || hc == NULL)
    return NULL;

  hh = msg_hclass_offset((void *)pub->msg_ident, (msg_pub_t *)pub, hc);

  if (hh)
    return *hh;
  else 
    return NULL;
}

#include <sofia-sip/su_uniqueid.h>

/** Generates a random token.
 *
 */
int msg_random_token(char token[], int tlen, 
		     void const *rmemp, int rsize)
{
  uint32_t random = 0, rword;
  uint8_t rbyte;
  uint8_t const *rmem = rmemp;
  int i, n;

  static char const token_chars[32] = 
    /* Create aesthetically pleasing raNDom capS LooK */
    "aBcDeFgHjKmNpQrStUvXyZ0123456789";

  if (rmem == NULL && rsize == 0)
    rsize = UINT_MAX;

  if (rsize == 0) {
    if (token && tlen > 0)
      strcpy(token, "+");
    return 1;
  }

  if (token == NULL) {
    if (rsize >= tlen * 5 / 8)
      return tlen;
    else
      return rsize / 5 * 8;
  }
    
  for (i = 0, n = 0; i < tlen;) {
    if (n < 5) {
      if (rsize == 0)
	;
      else if (rmem) {
	rbyte = *rmem++, rsize--;
	random = random | (rbyte << n);
	n += 8;
      } else {
	rword = su_randint(0, UINT_MAX);
	random = (rword >> 13) & 31;
	n = 6;
      }
    }

    token[i] = token_chars[random & 31];
    random >>= 5;
    i++, n -= 5;

    if (n < 0 || (n == 0 && rsize == 0))
      break;
  }
  
  token[i] = 0;

  return i;
}