libcoap  4.3.0beta
coap_string(3)
coap_string

NAME

coap_string, coap_new_string, coap_delete_string, coap_new_str_const, coap_delete_str_const, coap_new_binary, coap_delete_binary, coap_resize_binary, coap_new_bin_const — Work with CoAP string functions

SYNOPSIS

#include <coap2/coap.h>

coap_string_t *coap_new_string(size_t size);

void coap_delete_string(coap_string_t *string);

coap_str_const_t *coap_new_str_const(const uint8_t *data, size_t size);

void coap_delete_str_const(coap_str_const_t *string);

coap_str_const_t *coap_make_str_const(const char *string);

int coap_string_equal(coap_string_t string1, coap_string_t string2);

coap_binary_t *coap_new_binary(size_t size);

void coap_delete_binary(coap_binary_t *binary);

coap_binary_t *coap_resize_binary(coap_binary_t *binary, size_t new_size);

coap_bin_const_t *coap_new_bin_const(const uint8_t *data, size_t size);

void coap_delete_bin_const(coap_bin_const_t *binary);

int coap_binary_equal(coap_binary_t binary1, coap_binary_t binary2);

Link with -lcoap-2, -lcoap-2-gnutls, -lcoap-2-openssl, -lcoap-2-mbedtls or -lcoap-2-tinydtls depending on your (D)TLS library type.

DESCRIPTION

There is support for storing strings (usually readable data) and for storing binary data. These are used by a number of functions and provide the information in some of the callbacks.

There are 4 supported string/binary types as follows

/*
 * Coap string data definition
 */
typedef struct coap_string_t {
  size_t length;    /* length of string */
  uint8_t *s;       /* string data */
} coap_string_t;

/*
 * Coap string data definition with const data
 */
typedef struct coap_str_const_t {
  size_t length;    /* length of string */
  const uint8_t *s; /* read-only string data */
} coap_str_const_t;

/*
 * Coap binary data definition
 */
typedef struct coap_binary_t {
  size_t length;    /* length of binary data */
  uint8_t *s;       /* binary data */
} coap_binary_t;

/*
 * Coap binary data definition with const data
 */
typedef struct coap_bin_const_t {
  size_t length;    /* length of binary data */
  const uint8_t *s; /* read-only binary data */
} coap_bin_const_t;

The coap_new_string() function allocates a new coap_string_t of size where s points to uninitialized data of length size with an extra trailing NULL at size + 1. length is set to size.

The coap_delete_string() function is used to delete the coap_string_t created by coap_new_string().

The coap_new_str_const() function allocates a coap_str_const_t of size where s is filled in with data and has a trailing NULL added. length is set to size. s is read-only.

The coap_delete_str_const() function is used to delete the coap_str_const_t created by coap_new_str_const().

The coap_make_str_const() function is used to take some read-only text and uses a static coap_str_const_t for use in different function calls. There are two static entries that are cycled through so that a single function call can call coap_make_str_const() twice.

The coap_string_equal() function is used to compare two different string objects string1 and string2.

The coap_new_binary() function allocates a new coap_binary_t of size where s points to uninitialized data of length size. length is set to size.

The coap_resize_binary() function is used resize the size of s to the new size of new_size. The data between the old length and the new_size is unitialized. length is set to new_size.

The coap_delete_binary() function is used to delete the coap_binary_t created by coap_new_binary().

The coap_new_bin_const() function allocates a coap_bin_const_t of size where s is filled in with in with data and has a trailing NULL added. length is set to size. s is read-only.

The coap_delete_bin_const() function is used to delete the coap_bin_const_t created by coap_new_bin_const().

The coap_binary_equal() function is used to compare two different binary objects binary1 and binary2.

RETURN VALUES

The coap_new_string() function returns a pointer to an allocated coap_string_t or NULL if there was a failure.

The coap_new_str_const() function returns a pointer to an allocated coap_str_const_t or NULL if there was a failure.

The coap_new_binary() function returns a pointer to an allocated coap_binary_t or NULL if there was a failure.

The coap_resize_binary() function returns a pointer to an re-allocated coap_binary_t or NULL if there was a failure.

The coap_new_bin_const() function returns a pointer to an allocated coap_bin_const_t or NULL if there was a failure.

FURTHER INFORMATION

"RFC7252: The Constrained Application Protocol (CoAP)"

BUGS

Please report bugs on the mailing list for libcoap: libcoap-developers@lists.sourceforge.net or raise an issue on GitHub at https://github.com/obgm/libcoap/issues

AUTHORS

The libcoap project <libcoap-developers@lists.sourceforge.net>

coap_string(3)