libcouchbase_arithmetic

typedef struct
{
    int   *cntr;
} CounterT;
 
/* the callback invoked by the library when receiving an error */
static void error_callback(libcouchbase_t instance,
        libcouchbase_error_t error,
        const char *errinfo)
{
    (void)instance;
    fprintf(stderr, "Error %d", error);
    if (errinfo) {
        fprintf(stderr, ": %s", errinfo);
    }
    fprintf(stderr, "\n");
    exit(EXIT_FAILURE);
}
 
static void arithmetic_callback(
        libcouchbase_t instance, const void *cookie,
        libcouchbase_error_t err, const void *key, size_t nkey,
        uint64_t value, uint64_t cas)
{
    CounterT* counter = (CounterT*) cookie;
    (void)instance; (void)cookie; (void)cas;
    printf("Get callback received\n");
 
    *(counter->cntr) = value;
    printf("Value : %u", value);
}
 
int incrCounterVal(const char* key, const int keyLen)
{
    libcouchbase_error_t oprc;  /* for checking various responses */
 
    oprc= libcouchbase_arithmetic(mInstance,
            NULL, // cookie
            key,
            keyLen,
            1,
            0,
            1,
            1);
    if (oprc != LIBCOUCHBASE_SUCCESS) {
        printf("\nFailed to do increment operation %d\n", oprc);
        return 0;
    }
 
    /* Wait for the operation to compelete */
    libcouchbase_wait(mInstance);
 
    oprc = libcouchbase_get_last_error(mInstance);
    if (oprc == LIBCOUCHBASE_SUCCESS) {
    } else {
        printf("Could not set hello.  Error received is %d", oprc);
        return 0;
    }
 
    return 1;
}
 
int getCounterValue(const char* key, const int keyLen, int *counter1)
{
    const char* keys[1];
    size_t nkey[1];
 
    CounterT counter;
    libcouchbase_error_t oprc;  /* for checking various responses */
 
 
    keys[0] = key;
    nkey[0] = keyLen;
    counter.cntr = counter1;
 
    oprc = libcouchbase_mget(mInstance,
            &counter,
            1,
            (const void*const*)keys,
            nkey,
            NULL);
 
    if (oprc != LIBCOUCHBASE_SUCCESS) {
        printf("\nFailed to  operation\n");
        return 0;
    }
 
    /* Wait for the operation to compelete */
    libcouchbase_wait(mInstance);
 
 
    return 1;
}
 
int main(int argc, char **argv)
{
 
    const char *host = "localhost:8091";
    const char *username = NULL;
    const char *passwd = NULL;
    const char *bucket = "default";
    char key1[] = "Counter" ;
    unsigned int counter1, counter2;
 
    mInstance = libcouchbase_create(host, username,
            passwd, bucket, NULL);
    if (mInstance == NULL) {
        fprintf(stderr, "Failed to create libcouchbase instance\n");
        return 1;
    }
 
    (void)libcouchbase_set_error_callback(mInstance, error_callback);
    (void)libcouchbase_set_arithmetic_callback(mInstance, arithmetic_callback);
 
    if (libcouchbase_connect(mInstance) != LIBCOUCHBASE_SUCCESS) {
        fprintf(stderr, "Failed to connect libcouchbase instance to server\n");
        return 1;
    }
 
 
   incrCounterVal(key1, strlen(key1));
   incrCounterVal(key1, strlen(key1));
   getCounterValue(key1, strlen(key1), &counter1);
   printf("Counter 1 : %d\n", counter1);
}