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#include <errno.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "cache.h"
#define MAX_RANDOM_ENTRIES 32
struct key_record {
char *key;
char *value;
};
int generate_random_entry(struct key_record **entry);
int generate_random_string(char **dst, const size_t len);
void free_random_entry(void *entry);
void *producer(void *arg)
{
struct foo_cache *cache = arg;
int i;
for (i = 0; i < MAX_RANDOM_ENTRIES; i++) {
struct key_record *entry = NULL;
if (generate_random_entry(&entry)) {
fprintf(stderr, "generate_random_entry() failed\n");
continue;
}
#if defined(DEBUG)
printf("Random Entry:\n");
printf(" key: %s\n", entry->key);
printf(" Key: %s\n", entry->value);
#else
printf("inserted %s (%d)\n", entry->key,
(int)strlen(entry->key));
#endif
if (foo_cache_insert(cache, entry->key, entry)) {
fprintf(stderr, "foo_cache_insert() failed\n");
continue;
}
}
pthread_exit(NULL);
}
void *consumer(void *arg)
{
struct foo_cache *cache = arg;
struct key_record *result = NULL;
char *buffer = malloc(64);
char key[33];
int stop = 0;
if (!buffer)
goto out;
/* give producer time to populate the cache */
sleep(2);
printf("\n\n");
do {
memset(key, 0, 64);
result = NULL;
printf("Enter key for lookup: ");
fgets(buffer, sizeof(key), stdin);
sscanf(buffer, "%s\n", key);
/* read '\n' from stdin */
getchar();
if (strncmp(key, "exit", 4) == 0) {
stop = 1;
continue;
}
printf("Got key %s (%d)\n", key, (int)strlen(key));
if (foo_cache_lookup(cache, key, &result)) {
fprintf(stderr, "Could not retrieve key %s\n", key);
continue;
}
if (!result) {
printf("MISS\n");
continue;
}
printf("HIT\n");
printf("key: %s\n", result->key);
printf("key : %s\n", result->value);
} while (!stop);
out:
if (buffer)
free(buffer);
pthread_exit(NULL);
}
int main()
{
int rv;
struct foo_cache *cache = NULL;
pthread_t workers[2];
rv = foo_cache_create(&cache, MAX_RANDOM_ENTRIES / 2,
free_random_entry);
if (rv) {
fprintf(stderr, "Could not create cache\n");
exit(1);
}
(void)pthread_create(&workers[0], NULL, producer, (void *)cache);
(void)pthread_create(&workers[1], NULL, consumer, (void *)cache);
pthread_join(workers[0], NULL);
pthread_join(workers[1], NULL);
(void)foo_cache_delete(cache, 0);
return 0;
}
int generate_random_entry(struct key_record **entry)
{
struct key_record *new = NULL;
char *key = NULL;
char *value = NULL;
int rv;
if (!entry)
return EINVAL;
rv = generate_random_string(&key, 33);
if (rv)
return rv;
rv = generate_random_string(&value, 129);
if (rv)
return rv;
if ((new = malloc(sizeof(*new))) == NULL) {
free(key);
free(value);
return ENOMEM;
}
new->key = key;
new->value = value;
*entry = new;
return 0;
}
int generate_random_string(char **dst, const size_t len)
{
static const char alphanum[] =
"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
size_t i;
char *s;
if (!dst || len == 0)
return EINVAL;
if ((s = malloc(len)) == NULL)
return ENOMEM;
for (i = 0; i < len - 1; i++) {
s[i] = alphanum[rand() % (sizeof(alphanum) - 1)];
}
s[len - 1] = '\0';
*dst = s;
return 0;
}
void free_random_entry(void *entry)
{
#if defined(DEBUG)
fprintf(stderr, "In %s: entry @ %p\n", __func__, entry);
#endif
struct key_record *record = entry;
if (!record)
return;
if (record->key)
free(record->key);
if (record->value)
free(record->value);
free(record);
record = NULL;
}
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