1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
#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;
}
|