--- /dev/null
+#include <stdio.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <string.h>
+#include <assert.h>
+
+#include "adu.h"
+#include "string.h"
+#include "bloom.h"
+
+#ifdef TEST_BLOOM
+void *adu_calloc(size_t size)
+{
+ void *ret = malloc(size);
+ memset(ret, 0, size);
+ return ret;
+}
+#undef INFO_LOG
+#define INFO_LOG printf
+#endif
+
+static inline uint64_t filter_bits(struct bloom *b)
+{
+ return 1ULL << b->order;
+}
+
+/*
+ * SuperFastHash, by Paul Hsieh.
+ * http://www.azillionmonkeys.com/qed/hash.html
+ */
+
+#if (defined(__GNUC__) && defined(__i386__))
+#define get16bits(d) (*((const uint16_t *) (d)))
+#else
+#define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8)\
+ +(uint32_t)(((const uint8_t *)(d))[0]) )
+#endif
+
+
+static uint32_t super_fast_hash(const uint8_t *data, uint32_t len, uint32_t hash)
+{
+ uint32_t tmp;
+ int rem = len & 3;
+
+ len >>= 2;
+
+ for (;len > 0; len--) {
+ hash += get16bits (data);
+ tmp = (get16bits (data+2) << 11) ^ hash;
+ hash = (hash << 16) ^ tmp;
+ data += 2*sizeof (uint16_t);
+ hash += hash >> 11;
+ }
+
+ /* Handle end cases */
+ switch (rem) {
+ case 3:
+ hash += get16bits (data);
+ hash ^= hash << 16;
+ hash ^= data[sizeof (uint16_t)] << 18;
+ hash += hash >> 11;
+ break;
+ case 2:
+ hash += get16bits (data);
+ hash ^= hash << 11;
+ hash += hash >> 17;
+ break;
+ case 1:
+ hash += *data;
+ hash ^= hash << 10;
+ hash += hash >> 1;
+ }
+ /* Force "avalanching" of final 127 bits */
+ hash ^= hash << 3;
+ hash += hash >> 5;
+ hash ^= hash << 4;
+ hash += hash >> 17;
+ hash ^= hash << 25;
+ hash += hash >> 6;
+ return hash;
+}
+
+static int test_and_set_bit(uint64_t bitnum, struct bloom *b)
+{
+ uint64_t byte = bitnum / 8;
+ uint8_t bit = 1 << (bitnum % 8);
+ int ret = b->filter[byte] & bit;
+
+ b->filter[byte] |= bit;
+
+ if (!ret)
+ b->num_set_bits++;
+ return ret;
+}
+
+int bloom_test_and_insert(const uint8_t *data, size_t len, struct bloom *b)
+{
+ int i, ret = 0;
+ uint32_t h = 0xb11924e1; /* some arbitrary value */
+
+ for (i = 1; i < b->num_hash_functions; i++) {
+ uint64_t bitnum = super_fast_hash(data, len, h);
+ h = bitnum;
+ if (b->order > 32) {
+ bitnum = bitnum << 32;
+ h = super_fast_hash(data, len, h);
+ bitnum |= h;
+ }
+ bitnum &= filter_bits(b) - 1;
+ ret |= !test_and_set_bit(bitnum, b);
+ }
+ if (ret)
+ b->num_entries++;
+ return !ret;
+}
+
+int bloom_test_and_insert_string(const char *str, struct bloom *b)
+{
+ uint32_t len = strlen(str);
+
+ return bloom_test_and_insert((const uint8_t *)str, len, b);
+}
+
+void bloom_free(struct bloom *b)
+{
+ if (!b)
+ return;
+ free(b->filter);
+ free(b);
+}
+
+int bloom_init(unsigned order, unsigned num_hash_functions,
+ struct bloom **result)
+{
+ struct bloom *b = adu_calloc(sizeof(*b));
+
+ INFO_LOG("allocating bloom filter (order: %u, %u hash functions)\n",
+ order, num_hash_functions);
+ b->order = order;
+ b->num_hash_functions = num_hash_functions;
+ b->filter = adu_calloc(filter_bits(b) / 8);
+ *result = b;
+ return 1;
+}
+
+#ifdef TEST_BLOOM
+
+void add_stdin(struct bloom *b)
+{
+ char buf[255];
+ unsigned false_positives = 0;
+
+ while (fgets(buf, sizeof(buf) - 1, stdin)) {
+ size_t len = strlen(buf);
+ if (!len)
+ continue;
+ if (buf[len - 1] == '\n')
+ buf[len - 1] = '\0';
+ if (bloom_test_and_insert_string(buf, b))
+ false_positives++;
+ }
+ INFO_LOG("filter contains %llu entries\n", b->num_entries);
+ printf("%u possible false positives\n", false_positives);
+}
+
+int main(int argc, char **argv)
+{
+ struct bloom *b;
+
+ if (argc != 3) {
+ printf("usage: $0 j k\n");
+ printf("j: set bloom filter size to m=2^j bits\n");
+ printf("k: # of hash functions to use\n");
+ exit(1);
+ }
+ bloom_init(atoi(argv[1]), atoi(argv[2]), &b);
+ add_stdin(b);
+ INFO_LOG("%u%% of bits are set\n", (unsigned)
+ (b->num_set_bits * 100ULL / filter_bits(b)));
+ return 1;
+}
+
+#endif /* TEST_BLOOM */
#include "string.h"
#include "error.h"
#include "user.h"
+#include "bloom.h"
/* Id of the device containing the base dir. */
static dev_t device_id;
+static struct bloom *global_bloom_filter;
+static struct bloom *user_bloom_filter;
+
+static int consider_bloom(struct stat64 *s)
+{
+ if (!global_bloom_filter)
+ return 0;
+ if (s->st_nlink <= 1)
+ return 0;
+ return 1;
+}
+
+#define GLOBAL_BLOOM_BUF_SIZE (sizeof(ino_t) + sizeof(dev_t) + sizeof(off_t))
+#define USER_BLOOM_BUF_SIZE (GLOBAL_BLOOM_BUF_SIZE + sizeof(uid_t))
+
+static void make_bloom_buf(struct stat64 *s, uint8_t buf[USER_BLOOM_BUF_SIZE])
+{
+ uint8_t *p = buf;
+
+ if (!consider_bloom(s))
+ return;
+ memcpy(p, &s->st_ino, sizeof(ino_t));
+ p += sizeof(ino_t);
+ memcpy(p, &s->st_dev, sizeof(dev_t));
+ p += sizeof(dev_t);
+ memcpy(p, &s->st_size, sizeof(off_t));
+ p += sizeof(off_t);
+ memcpy(p, &s->st_uid, sizeof(uid_t));
+}
+
+static int insert_global_bloom(struct stat64 *s,
+ uint8_t buf[USER_BLOOM_BUF_SIZE])
+{
+ if (!consider_bloom(s))
+ return 0;
+ return bloom_test_and_insert(buf, GLOBAL_BLOOM_BUF_SIZE,
+ global_bloom_filter);
+}
+
+static int insert_user_bloom(struct stat64 *s,
+ uint8_t buf[USER_BLOOM_BUF_SIZE])
+{
+ if (!consider_bloom(s))
+ return 0;
+ return bloom_test_and_insert(buf, USER_BLOOM_BUF_SIZE,
+ user_bloom_filter);
+}
static int add_directory(char *dirname, uint64_t *dir_num, uint64_t *parent_dir_num,
uint64_t *dir_size, uint64_t *dir_files)
}
static int update_user_row(struct osl_table *t, uint64_t dir_num,
- uint64_t *add)
+ uint64_t add)
{
struct osl_row *row;
struct osl_object obj = {.data = &dir_num, .size = sizeof(dir_num)};
objects[UT_DIR_NUM].data = &dir_num;
objects[UT_DIR_NUM].size = sizeof(dir_num);
- objects[UT_BYTES].data = add;
- objects[UT_BYTES].size = sizeof(*add);
+ objects[UT_BYTES].data = &add;
+ objects[UT_BYTES].size = sizeof(add);
objects[UT_FILES].data = &num_files;
objects[UT_FILES].size = sizeof(num_files);
ret = osl(osl_add_row(t, objects));
ret = osl(osl_get_object(t, row, UT_BYTES, &obj1));
if (ret < 0)
return ret;
- num = *(uint64_t *)obj1.data + *add;
+ num = *(uint64_t *)obj1.data + add;
ret = osl(osl_update_object(t, row, UT_BYTES, &obj2));
if (ret < 0)
return ret;
uint64_t dir_size = 0, dir_files = 0;
/* dir count. */
static uint64_t current_dir_num;
-
uint64_t this_dir_num = ++current_dir_num;
check_signals();
while ((entry = readdir(dir))) {
mode_t m;
struct stat64 s;
- uint32_t uid;
- uint64_t size;
struct user_info *ui;
+ uint8_t bloom_buf[USER_BLOOM_BUF_SIZE];
if (!strcmp(entry->d_name, "."))
continue;
if (S_ISDIR(m)) {
if (conf.one_file_system_given && s.st_dev != device_id)
continue;
+ dir_size += s.st_size;
+ dir_files++;
+ ret = create_user_table(s.st_uid, &ui);
+ if (ret < 0)
+ goto out;
+ ret = update_user_row(ui->table, this_dir_num,
+ s.st_size);
+ if (ret < 0)
+ goto out;
ret = scan_dir(entry->d_name, &this_dir_num);
if (ret < 0)
goto out;
continue;
}
+
/* regular file */
- size = s.st_size;
- dir_size += size;
+ make_bloom_buf(&s, bloom_buf);
+ if (insert_global_bloom(&s, bloom_buf))
+ DEBUG_LOG("global hard link: %s/%s\n", dirname,
+ entry->d_name);
+ else
+ dir_size += s.st_size;
dir_files++;
- uid = s.st_uid;
- ret = create_user_table(uid, &ui);
+ ret = create_user_table(s.st_uid, &ui);
if (ret < 0)
goto out;
- ret = update_user_row(ui->table, this_dir_num, &size);
+ ret = insert_user_bloom(&s, bloom_buf);
+ if (ret)
+ DEBUG_LOG("hard link for uid %d: %s/%s\n",
+ (unsigned)s.st_uid, dirname, entry->d_name);
+ ret = update_user_row(ui->table, this_dir_num,
+ ret? 0 : s.st_size);
if (ret < 0)
goto out;
}
return ret;
}
+static void log_bloom_stat(struct bloom *b)
+{
+ unsigned percent;
+
+ NOTICE_LOG("\tfilter contains %llu entries\n",
+ (long long unsigned)b->num_entries);
+ percent = b->num_set_bits * 100ULL / (1ULL << b->order);
+ NOTICE_LOG("\t%u%% of bits are set\n", percent);
+ if (percent > 50) {
+ WARNING_LOG("results may be unreliable!\n");
+ WARNING_LOG("consider incrasing bllom filter size\n");
+ }
+}
+
+static void log_bloom_stats(void)
+{
+ struct bloom *b = global_bloom_filter;
+ if (!b)
+ return;
+ NOTICE_LOG("global bloom filter statistics:\n");
+ log_bloom_stat(b);
+ NOTICE_LOG("user bloom filter statistics:\n");
+ b = user_bloom_filter;
+ log_bloom_stat(b);
+}
+
/**
* The main function of the create mode.
*
int com_create(void)
{
uint64_t zero = 0ULL;
- int ret;
+ int ret, order = conf.bloom_filter_order_arg,
+ num = conf.num_bloom_filter_hash_functions_arg;
struct stat statbuf;
if (lstat(conf.base_dir_arg, &statbuf) == -1)
return -ERRNO_TO_ERROR(errno);
if (!S_ISDIR(statbuf.st_mode))
return -ERRNO_TO_ERROR(ENOTDIR);
+ if (order >= 10 && num > 0) {
+ bloom_init(order, num, &global_bloom_filter);
+ bloom_init(order, num, &user_bloom_filter);
+ } else
+ WARNING_LOG("hard link detection deactivated\n");
device_id = statbuf.st_dev;
create_hash_table(conf.hash_table_bits_arg);
ret = open_dir_table(1);
if (ret < 0)
- return ret;
+ goto out;
check_signals();
ret = scan_dir(conf.base_dir_arg, &zero);
if (ret < 0)
goto out;
ret = write_uid_file();
+ log_bloom_stats();
out:
+ bloom_free(global_bloom_filter);
+ bloom_free(user_bloom_filter);
return ret;
}
projects / adu.git / commitdiff