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-rw-r--r--girepository/cmph/fch.c517
1 files changed, 517 insertions, 0 deletions
diff --git a/girepository/cmph/fch.c b/girepository/cmph/fch.c
new file mode 100644
index 00000000..67b68fbb
--- /dev/null
+++ b/girepository/cmph/fch.c
@@ -0,0 +1,517 @@
+#include "fch.h"
+#include "cmph_structs.h"
+#include "fch_structs.h"
+#include "hash.h"
+#include "bitbool.h"
+#include "fch_buckets.h"
+#include <math.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include <string.h>
+#define INDEX 0 /* alignment index within a bucket */
+//#define DEBUG
+#include "debug.h"
+
+static fch_buckets_t * mapping(cmph_config_t *mph);
+static cmph_uint32 * ordering(fch_buckets_t * buckets);
+static cmph_uint8 check_for_collisions_h2(fch_config_data_t *fch, fch_buckets_t * buckets, cmph_uint32 *sorted_indexes);
+static void permut(cmph_uint32 * vector, cmph_uint32 n);
+static cmph_uint8 searching(fch_config_data_t *fch, fch_buckets_t *buckets, cmph_uint32 *sorted_indexes);
+
+fch_config_data_t *fch_config_new()
+{
+ fch_config_data_t *fch;
+ fch = (fch_config_data_t *)malloc(sizeof(fch_config_data_t));
+ assert(fch);
+ memset(fch, 0, sizeof(fch_config_data_t));
+ fch->hashfuncs[0] = CMPH_HASH_JENKINS;
+ fch->hashfuncs[1] = CMPH_HASH_JENKINS;
+ fch->m = fch->b = 0;
+ fch->c = fch->p1 = fch->p2 = 0.0;
+ fch->g = NULL;
+ fch->h1 = NULL;
+ fch->h2 = NULL;
+ return fch;
+}
+
+void fch_config_destroy(cmph_config_t *mph)
+{
+ fch_config_data_t *data = (fch_config_data_t *)mph->data;
+ //DEBUGP("Destroying algorithm dependent data\n");
+ free(data);
+}
+
+void fch_config_set_hashfuncs(cmph_config_t *mph, CMPH_HASH *hashfuncs)
+{
+ fch_config_data_t *fch = (fch_config_data_t *)mph->data;
+ CMPH_HASH *hashptr = hashfuncs;
+ cmph_uint32 i = 0;
+ while(*hashptr != CMPH_HASH_COUNT)
+ {
+ if (i >= 2) break; //fch only uses two hash functions
+ fch->hashfuncs[i] = *hashptr;
+ ++i, ++hashptr;
+ }
+}
+
+cmph_uint32 mixh10h11h12(cmph_uint32 b, double p1, double p2, cmph_uint32 initial_index)
+{
+ register cmph_uint32 int_p2 = (cmph_uint32)p2;
+ if (initial_index < p1) initial_index %= int_p2; /* h11 o h10 */
+ else { /* h12 o h10 */
+ initial_index %= b;
+ if(initial_index < p2) initial_index += int_p2;
+ }
+ return initial_index;
+}
+
+
+cmph_uint32 fch_calc_b(double c, cmph_uint32 m)
+{
+ return (cmph_uint32)ceil((c*m)/(log((double)m)/log(2.0) + 1));
+}
+
+double fch_calc_p1(cmph_uint32 m)
+{
+ return ceil(0.55*m);
+}
+
+double fch_calc_p2(cmph_uint32 b)
+{
+ return ceil(0.3*b);
+}
+
+static fch_buckets_t * mapping(cmph_config_t *mph)
+{
+ cmph_uint32 i = 0;
+ fch_buckets_t *buckets = NULL;
+ fch_config_data_t *fch = (fch_config_data_t *)mph->data;
+ if (fch->h1) hash_state_destroy(fch->h1);
+ fch->h1 = hash_state_new(fch->hashfuncs[0], fch->m);
+ fch->b = fch_calc_b(fch->c, fch->m);
+ fch->p1 = fch_calc_p1(fch->m);
+ fch->p2 = fch_calc_p2(fch->b);
+ //DEBUGP("b:%u p1:%f p2:%f\n", fch->b, fch->p1, fch->p2);
+ buckets = fch_buckets_new(fch->b);
+
+ mph->key_source->rewind(mph->key_source->data);
+ for(i = 0; i < fch->m; i++)
+ {
+ cmph_uint32 h1, keylen;
+ char *key = NULL;
+ mph->key_source->read(mph->key_source->data, &key, &keylen);
+ h1 = hash(fch->h1, key, keylen) % fch->m;
+ h1 = mixh10h11h12 (fch->b, fch->p1, fch->p2, h1);
+ fch_buckets_insert(buckets, h1, key, keylen);
+ key = NULL; // transger memory ownership
+
+ }
+ return buckets;
+}
+
+
+// returns the buckets indexes sorted by their sizes.
+static cmph_uint32 * ordering(fch_buckets_t * buckets)
+{
+ return fch_buckets_get_indexes_sorted_by_size(buckets);
+}
+
+/* Check whether function h2 causes collisions among the keys of each bucket */
+static cmph_uint8 check_for_collisions_h2(fch_config_data_t *fch, fch_buckets_t * buckets, cmph_uint32 *sorted_indexes)
+{
+ //cmph_uint32 max_size = fch_buckets_get_max_size(buckets);
+ cmph_uint8 * hashtable = (cmph_uint8 *)calloc((size_t)fch->m, sizeof(cmph_uint8));
+ cmph_uint32 nbuckets = fch_buckets_get_nbuckets(buckets);
+ cmph_uint32 i = 0, index = 0, j =0;
+ for (i = 0; i < nbuckets; i++)
+ {
+ cmph_uint32 nkeys = fch_buckets_get_size(buckets, sorted_indexes[i]);
+ memset(hashtable, 0, (size_t)fch->m);
+ //DEBUGP("bucket %u -- nkeys: %u\n", i, nkeys);
+ for (j = 0; j < nkeys; j++)
+ {
+ char * key = fch_buckets_get_key(buckets, sorted_indexes[i], j);
+ cmph_uint32 keylen = fch_buckets_get_keylength(buckets, sorted_indexes[i], j);
+ index = hash(fch->h2, key, keylen) % fch->m;
+ if(hashtable[index]) { // collision detected
+ free(hashtable);
+ return 1;
+ }
+ hashtable[index] = 1;
+ }
+ }
+ free(hashtable);
+ return 0;
+}
+
+static void permut(cmph_uint32 * vector, cmph_uint32 n)
+{
+ cmph_uint32 i, j, b;
+ for (i = 0; i < n; i++) {
+ j = (cmph_uint32) rand() % n;
+ b = vector[i];
+ vector[i] = vector[j];
+ vector[j] = b;
+ }
+}
+
+static cmph_uint8 searching(fch_config_data_t *fch, fch_buckets_t *buckets, cmph_uint32 *sorted_indexes)
+{
+ cmph_uint32 * random_table = (cmph_uint32 *) calloc((size_t)fch->m, sizeof(cmph_uint32));
+ cmph_uint32 * map_table = (cmph_uint32 *) calloc((size_t)fch->m, sizeof(cmph_uint32));
+ cmph_uint32 iteration_to_generate_h2 = 0;
+ cmph_uint32 searching_iterations = 0;
+ cmph_uint8 restart = 0;
+ cmph_uint32 nbuckets = fch_buckets_get_nbuckets(buckets);
+ cmph_uint32 i, j, z, counter = 0, filled_count = 0;
+ if (fch->g) free (fch->g);
+ fch->g = (cmph_uint32 *) calloc((size_t)fch->b, sizeof(cmph_uint32));
+
+ //DEBUGP("max bucket size: %u\n", fch_buckets_get_max_size(buckets));
+
+ for(i = 0; i < fch->m; i++)
+ {
+ random_table[i] = i;
+ }
+ permut(random_table, fch->m);
+ for(i = 0; i < fch->m; i++)
+ {
+ map_table[random_table[i]] = i;
+ }
+ do {
+ if (fch->h2) hash_state_destroy(fch->h2);
+ fch->h2 = hash_state_new(fch->hashfuncs[1], fch->m);
+ restart = check_for_collisions_h2(fch, buckets, sorted_indexes);
+ filled_count = 0;
+ if (!restart)
+ {
+ searching_iterations++; iteration_to_generate_h2 = 0;
+ //DEBUGP("searching_iterations: %u\n", searching_iterations);
+ }
+ else {
+ iteration_to_generate_h2++;
+ //DEBUGP("iteration_to_generate_h2: %u\n", iteration_to_generate_h2);
+ }
+ for(i = 0; (i < nbuckets) && !restart; i++) {
+ cmph_uint32 bucketsize = fch_buckets_get_size(buckets, sorted_indexes[i]);
+ if (bucketsize == 0)
+ {
+ restart = 0; // false
+ break;
+ }
+ else restart = 1; // true
+ for(z = 0; (z < (fch->m - filled_count)) && restart; z++) {
+ char * key = fch_buckets_get_key(buckets, sorted_indexes[i], INDEX);
+ cmph_uint32 keylen = fch_buckets_get_keylength(buckets, sorted_indexes[i], INDEX);
+ cmph_uint32 h2 = hash(fch->h2, key, keylen) % fch->m;
+ counter = 0;
+ restart = 0; // false
+ fch->g[sorted_indexes[i]] = (fch->m + random_table[filled_count + z] - h2) % fch->m;
+ //DEBUGP("g[%u]: %u\n", sorted_indexes[i], fch->g[sorted_indexes[i]]);
+ j = INDEX;
+ do {
+ cmph_uint32 index = 0;
+ key = fch_buckets_get_key(buckets, sorted_indexes[i], j);
+ keylen = fch_buckets_get_keylength(buckets, sorted_indexes[i], j);
+ h2 = hash(fch->h2, key, keylen) % fch->m;
+ index = (h2 + fch->g[sorted_indexes[i]]) % fch->m;
+ //DEBUGP("key:%s keylen:%u index: %u h2:%u bucketsize:%u\n", key, keylen, index, h2, bucketsize);
+ if (map_table[index] >= filled_count) {
+ cmph_uint32 y = map_table[index];
+ cmph_uint32 ry = random_table[y];
+ random_table[y] = random_table[filled_count];
+ random_table[filled_count] = ry;
+ map_table[random_table[y]] = y;
+ map_table[random_table[filled_count]] = filled_count;
+ filled_count++;
+ counter ++;
+ }
+ else {
+ restart = 1; // true
+ filled_count = filled_count - counter;
+ counter = 0;
+ break;
+ }
+ j = (j + 1) % bucketsize;
+ } while(j % bucketsize != INDEX);
+ }
+ //getchar();
+ }
+ } while(restart && (searching_iterations < 10) && (iteration_to_generate_h2 < 1000));
+ free(map_table);
+ free(random_table);
+ return restart;
+}
+
+
+
+cmph_t *fch_new(cmph_config_t *mph, double c)
+{
+ cmph_t *mphf = NULL;
+ fch_data_t *fchf = NULL;
+ cmph_uint32 iterations = 100;
+ cmph_uint8 restart_mapping = 0;
+ fch_buckets_t * buckets = NULL;
+ cmph_uint32 * sorted_indexes = NULL;
+ fch_config_data_t *fch = (fch_config_data_t *)mph->data;
+ fch->m = mph->key_source->nkeys;
+ //DEBUGP("m: %f\n", fch->m);
+ if (c <= 2) c = 2.6; // validating restrictions over parameter c.
+ fch->c = c;
+ //DEBUGP("c: %f\n", fch->c);
+ fch->h1 = NULL;
+ fch->h2 = NULL;
+ fch->g = NULL;
+ do
+ {
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Entering mapping step for mph creation of %u keys\n", fch->m);
+ }
+ if (buckets) fch_buckets_destroy(buckets);
+ buckets = mapping(mph);
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Starting ordering step\n");
+ }
+ if (sorted_indexes) free (sorted_indexes);
+ sorted_indexes = ordering(buckets);
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Starting searching step.\n");
+ }
+ restart_mapping = searching(fch, buckets, sorted_indexes);
+ iterations--;
+
+ } while(restart_mapping && iterations > 0);
+ if (buckets) fch_buckets_destroy(buckets);
+ if (sorted_indexes) free (sorted_indexes);
+ if (iterations == 0) return NULL;
+ mphf = (cmph_t *)malloc(sizeof(cmph_t));
+ mphf->algo = mph->algo;
+ fchf = (fch_data_t *)malloc(sizeof(fch_data_t));
+ fchf->g = fch->g;
+ fch->g = NULL; //transfer memory ownership
+ fchf->h1 = fch->h1;
+ fch->h1 = NULL; //transfer memory ownership
+ fchf->h2 = fch->h2;
+ fch->h2 = NULL; //transfer memory ownership
+ fchf->p2 = fch->p2;
+ fchf->p1 = fch->p1;
+ fchf->b = fch->b;
+ fchf->c = fch->c;
+ fchf->m = fch->m;
+ mphf->data = fchf;
+ mphf->size = fch->m;
+ //DEBUGP("Successfully generated minimal perfect hash\n");
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Successfully generated minimal perfect hash function\n");
+ }
+ return mphf;
+}
+
+int fch_dump(cmph_t *mphf, FILE *fd)
+{
+ char *buf = NULL;
+ cmph_uint32 buflen;
+ register size_t nbytes;
+
+ fch_data_t *data = (fch_data_t *)mphf->data;
+ __cmph_dump(mphf, fd);
+
+ hash_state_dump(data->h1, &buf, &buflen);
+ //DEBUGP("Dumping hash state with %u bytes to disk\n", buflen);
+ nbytes = fwrite(&buflen, sizeof(cmph_uint32), (size_t)1, fd);
+ nbytes = fwrite(buf, (size_t)buflen, (size_t)1, fd);
+ free(buf);
+
+ hash_state_dump(data->h2, &buf, &buflen);
+ //DEBUGP("Dumping hash state with %u bytes to disk\n", buflen);
+ nbytes = fwrite(&buflen, sizeof(cmph_uint32), (size_t)1, fd);
+ nbytes = fwrite(buf, (size_t)buflen, (size_t)1, fd);
+ free(buf);
+
+ nbytes = fwrite(&(data->m), sizeof(cmph_uint32), (size_t)1, fd);
+ nbytes = fwrite(&(data->c), sizeof(double), (size_t)1, fd);
+ nbytes = fwrite(&(data->b), sizeof(cmph_uint32), (size_t)1, fd);
+ nbytes = fwrite(&(data->p1), sizeof(double), (size_t)1, fd);
+ nbytes = fwrite(&(data->p2), sizeof(double), (size_t)1, fd);
+ nbytes = fwrite(data->g, sizeof(cmph_uint32)*(data->b), (size_t)1, fd);
+ #ifdef DEBUG
+ cmph_uint32 i;
+ fprintf(stderr, "G: ");
+ for (i = 0; i < data->b; ++i) fprintf(stderr, "%u ", data->g[i]);
+ fprintf(stderr, "\n");
+ #endif
+ return 1;
+}
+
+void fch_load(FILE *f, cmph_t *mphf)
+{
+ char *buf = NULL;
+ cmph_uint32 buflen;
+ register size_t nbytes;
+ fch_data_t *fch = (fch_data_t *)malloc(sizeof(fch_data_t));
+
+ //DEBUGP("Loading fch mphf\n");
+ mphf->data = fch;
+ //DEBUGP("Reading h1\n");
+ fch->h1 = NULL;
+ nbytes = fread(&buflen, sizeof(cmph_uint32), (size_t)1, f);
+ //DEBUGP("Hash state of h1 has %u bytes\n", buflen);
+ buf = (char *)malloc((size_t)buflen);
+ nbytes = fread(buf, (size_t)buflen, (size_t)1, f);
+ fch->h1 = hash_state_load(buf, buflen);
+ free(buf);
+
+ //DEBUGP("Loading fch mphf\n");
+ mphf->data = fch;
+ //DEBUGP("Reading h2\n");
+ fch->h2 = NULL;
+ nbytes = fread(&buflen, sizeof(cmph_uint32), (size_t)1, f);
+ //DEBUGP("Hash state of h2 has %u bytes\n", buflen);
+ buf = (char *)malloc((size_t)buflen);
+ nbytes = fread(buf, (size_t)buflen, (size_t)1, f);
+ fch->h2 = hash_state_load(buf, buflen);
+ free(buf);
+
+
+ //DEBUGP("Reading m and n\n");
+ nbytes = fread(&(fch->m), sizeof(cmph_uint32), (size_t)1, f);
+ nbytes = fread(&(fch->c), sizeof(double), (size_t)1, f);
+ nbytes = fread(&(fch->b), sizeof(cmph_uint32), (size_t)1, f);
+ nbytes = fread(&(fch->p1), sizeof(double), (size_t)1, f);
+ nbytes = fread(&(fch->p2), sizeof(double), (size_t)1, f);
+
+ fch->g = (cmph_uint32 *)malloc(sizeof(cmph_uint32)*fch->b);
+ nbytes = fread(fch->g, fch->b*sizeof(cmph_uint32), (size_t)1, f);
+ #ifdef DEBUG
+ cmph_uint32 i;
+ fprintf(stderr, "G: ");
+ for (i = 0; i < fch->b; ++i) fprintf(stderr, "%u ", fch->g[i]);
+ fprintf(stderr, "\n");
+ #endif
+ return;
+}
+
+cmph_uint32 fch_search(cmph_t *mphf, const char *key, cmph_uint32 keylen)
+{
+ fch_data_t *fch = mphf->data;
+ cmph_uint32 h1 = hash(fch->h1, key, keylen) % fch->m;
+ cmph_uint32 h2 = hash(fch->h2, key, keylen) % fch->m;
+ h1 = mixh10h11h12 (fch->b, fch->p1, fch->p2, h1);
+ //DEBUGP("key: %s h1: %u h2: %u g[h1]: %u\n", key, h1, h2, fch->g[h1]);
+ return (h2 + fch->g[h1]) % fch->m;
+}
+void fch_destroy(cmph_t *mphf)
+{
+ fch_data_t *data = (fch_data_t *)mphf->data;
+ free(data->g);
+ hash_state_destroy(data->h1);
+ hash_state_destroy(data->h2);
+ free(data);
+ free(mphf);
+}
+
+/** \fn void fch_pack(cmph_t *mphf, void *packed_mphf);
+ * \brief Support the ability to pack a perfect hash function into a preallocated contiguous memory space pointed by packed_mphf.
+ * \param mphf pointer to the resulting mphf
+ * \param packed_mphf pointer to the contiguous memory area used to store the resulting mphf. The size of packed_mphf must be at least cmph_packed_size()
+ */
+void fch_pack(cmph_t *mphf, void *packed_mphf)
+{
+ fch_data_t *data = (fch_data_t *)mphf->data;
+ cmph_uint8 * ptr = packed_mphf;
+
+ // packing h1 type
+ CMPH_HASH h1_type = hash_get_type(data->h1);
+ *((cmph_uint32 *) ptr) = h1_type;
+ ptr += sizeof(cmph_uint32);
+
+ // packing h1
+ hash_state_pack(data->h1, ptr);
+ ptr += hash_state_packed_size(h1_type);
+
+ // packing h2 type
+ CMPH_HASH h2_type = hash_get_type(data->h2);
+ *((cmph_uint32 *) ptr) = h2_type;
+ ptr += sizeof(cmph_uint32);
+
+ // packing h2
+ hash_state_pack(data->h2, ptr);
+ ptr += hash_state_packed_size(h2_type);
+
+ // packing m
+ *((cmph_uint32 *) ptr) = data->m;
+ ptr += sizeof(data->m);
+
+ // packing b
+ *((cmph_uint32 *) ptr) = data->b;
+ ptr += sizeof(data->b);
+
+ // packing p1
+ *((cmph_uint64 *)ptr) = (cmph_uint64)data->p1;
+ ptr += sizeof(data->p1);
+
+ // packing p2
+ *((cmph_uint64 *)ptr) = (cmph_uint64)data->p2;
+ ptr += sizeof(data->p2);
+
+ // packing g
+ memcpy(ptr, data->g, sizeof(cmph_uint32)*(data->b));
+}
+
+/** \fn cmph_uint32 fch_packed_size(cmph_t *mphf);
+ * \brief Return the amount of space needed to pack mphf.
+ * \param mphf pointer to a mphf
+ * \return the size of the packed function or zero for failures
+ */
+cmph_uint32 fch_packed_size(cmph_t *mphf)
+{
+ fch_data_t *data = (fch_data_t *)mphf->data;
+ CMPH_HASH h1_type = hash_get_type(data->h1);
+ CMPH_HASH h2_type = hash_get_type(data->h2);
+
+ return (cmph_uint32)(sizeof(CMPH_ALGO) + hash_state_packed_size(h1_type) + hash_state_packed_size(h2_type) +
+ 4*sizeof(cmph_uint32) + 2*sizeof(double) + sizeof(cmph_uint32)*(data->b));
+}
+
+
+/** cmph_uint32 fch_search(void *packed_mphf, const char *key, cmph_uint32 keylen);
+ * \brief Use the packed mphf to do a search.
+ * \param packed_mphf pointer to the packed mphf
+ * \param key key to be hashed
+ * \param keylen key legth in bytes
+ * \return The mphf value
+ */
+cmph_uint32 fch_search_packed(void *packed_mphf, const char *key, cmph_uint32 keylen)
+{
+ register cmph_uint8 *h1_ptr = packed_mphf;
+ register CMPH_HASH h1_type = *((cmph_uint32 *)h1_ptr);
+ h1_ptr += 4;
+
+ register cmph_uint8 *h2_ptr = h1_ptr + hash_state_packed_size(h1_type);
+ register CMPH_HASH h2_type = *((cmph_uint32 *)h2_ptr);
+ h2_ptr += 4;
+
+ register cmph_uint32 *g_ptr = (cmph_uint32 *)(h2_ptr + hash_state_packed_size(h2_type));
+
+ register cmph_uint32 m = *g_ptr++;
+
+ register cmph_uint32 b = *g_ptr++;
+
+ register double p1 = (double)(*((cmph_uint64 *)g_ptr));
+ g_ptr += 2;
+
+ register double p2 = (double)(*((cmph_uint64 *)g_ptr));
+ g_ptr += 2;
+
+ register cmph_uint32 h1 = hash_packed(h1_ptr, h1_type, key, keylen) % m;
+ register cmph_uint32 h2 = hash_packed(h2_ptr, h2_type, key, keylen) % m;
+
+ h1 = mixh10h11h12 (b, p1, p2, h1);
+ return (h2 + g_ptr[h1]) % m;
+}
+
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