jsmn_value¶

Synopsis¶

typedef struct jsmn_value;

Jsmn does not favor NULL terminated strings and instead stores string data as a pointer length tuple. This is because jsmn does not allocate new strings to contain json data but instead collects pointers to the original memory. The jsmn_value tuple is a handle to a JSON token.

Members¶

const char *p

Pointer to the start of the JSON value
uint32_t len

Length of the JSON value

Examples¶

Read the “sub” key of a jwt token

const char *jwt = \
   "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9."\
   "eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ."\
   "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c";

jsmn_token_decode_s token;
err = jsmn_token_decode(&token, "your-256-bit-secret", JSMN_ALG_HS256, jwt, strlen(jwt));

if (!err) {
  jsmn_value sub;
  jsmn_token_get_claim_str(&token, "sub", &sub);
  printf("Hello %.*s!", sub.len, sub.p);
}