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-rw-r--r--girepository/cmph/bmz.c620
1 files changed, 620 insertions, 0 deletions
diff --git a/girepository/cmph/bmz.c b/girepository/cmph/bmz.c
new file mode 100644
index 00000000..51798a18
--- /dev/null
+++ b/girepository/cmph/bmz.c
@@ -0,0 +1,620 @@
+#include "graph.h"
+#include "bmz.h"
+#include "cmph_structs.h"
+#include "bmz_structs.h"
+#include "hash.h"
+#include "vqueue.h"
+#include "bitbool.h"
+
+#include <math.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include <string.h>
+
+//#define DEBUG
+#include "debug.h"
+
+static int bmz_gen_edges(cmph_config_t *mph);
+static cmph_uint8 bmz_traverse_critical_nodes(bmz_config_data_t *bmz, cmph_uint32 v, cmph_uint32 * biggest_g_value, cmph_uint32 * biggest_edge_value, cmph_uint8 * used_edges, cmph_uint8 * visited);
+static cmph_uint8 bmz_traverse_critical_nodes_heuristic(bmz_config_data_t *bmz, cmph_uint32 v, cmph_uint32 * biggest_g_value, cmph_uint32 * biggest_edge_value, cmph_uint8 * used_edges, cmph_uint8 * visited);
+static void bmz_traverse_non_critical_nodes(bmz_config_data_t *bmz, cmph_uint8 * used_edges, cmph_uint8 * visited);
+
+bmz_config_data_t *bmz_config_new()
+{
+ bmz_config_data_t *bmz = NULL;
+ bmz = (bmz_config_data_t *)malloc(sizeof(bmz_config_data_t));
+ assert(bmz);
+ memset(bmz, 0, sizeof(bmz_config_data_t));
+ bmz->hashfuncs[0] = CMPH_HASH_JENKINS;
+ bmz->hashfuncs[1] = CMPH_HASH_JENKINS;
+ bmz->g = NULL;
+ bmz->graph = NULL;
+ bmz->hashes = NULL;
+ return bmz;
+}
+
+void bmz_config_destroy(cmph_config_t *mph)
+{
+ bmz_config_data_t *data = (bmz_config_data_t *)mph->data;
+ DEBUGP("Destroying algorithm dependent data\n");
+ free(data);
+}
+
+void bmz_config_set_hashfuncs(cmph_config_t *mph, CMPH_HASH *hashfuncs)
+{
+ bmz_config_data_t *bmz = (bmz_config_data_t *)mph->data;
+ CMPH_HASH *hashptr = hashfuncs;
+ cmph_uint32 i = 0;
+ while(*hashptr != CMPH_HASH_COUNT)
+ {
+ if (i >= 2) break; //bmz only uses two hash functions
+ bmz->hashfuncs[i] = *hashptr;
+ ++i, ++hashptr;
+ }
+}
+
+cmph_t *bmz_new(cmph_config_t *mph, double c)
+{
+ cmph_t *mphf = NULL;
+ bmz_data_t *bmzf = NULL;
+ cmph_uint32 i;
+ cmph_uint32 iterations;
+ cmph_uint32 iterations_map = 20;
+ cmph_uint8 *used_edges = NULL;
+ cmph_uint8 restart_mapping = 0;
+ cmph_uint8 * visited = NULL;
+
+ bmz_config_data_t *bmz = (bmz_config_data_t *)mph->data;
+ if (c == 0) c = 1.15; // validating restrictions over parameter c.
+ DEBUGP("c: %f\n", c);
+ bmz->m = mph->key_source->nkeys;
+ bmz->n = (cmph_uint32)ceil(c * mph->key_source->nkeys);
+ DEBUGP("m (edges): %u n (vertices): %u c: %f\n", bmz->m, bmz->n, c);
+ bmz->graph = graph_new(bmz->n, bmz->m);
+ DEBUGP("Created graph\n");
+
+ bmz->hashes = (hash_state_t **)malloc(sizeof(hash_state_t *)*3);
+ for(i = 0; i < 3; ++i) bmz->hashes[i] = NULL;
+
+ do
+ {
+ // Mapping step
+ cmph_uint32 biggest_g_value = 0;
+ cmph_uint32 biggest_edge_value = 1;
+ iterations = 100;
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Entering mapping step for mph creation of %u keys with graph sized %u\n", bmz->m, bmz->n);
+ }
+ while(1)
+ {
+ int ok;
+ DEBUGP("hash function 1\n");
+ bmz->hashes[0] = hash_state_new(bmz->hashfuncs[0], bmz->n);
+ DEBUGP("hash function 2\n");
+ bmz->hashes[1] = hash_state_new(bmz->hashfuncs[1], bmz->n);
+ DEBUGP("Generating edges\n");
+ ok = bmz_gen_edges(mph);
+ if (!ok)
+ {
+ --iterations;
+ hash_state_destroy(bmz->hashes[0]);
+ bmz->hashes[0] = NULL;
+ hash_state_destroy(bmz->hashes[1]);
+ bmz->hashes[1] = NULL;
+ DEBUGP("%u iterations remaining\n", iterations);
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "simple graph creation failure - %u iterations remaining\n", iterations);
+ }
+ if (iterations == 0) break;
+ }
+ else break;
+ }
+ if (iterations == 0)
+ {
+ graph_destroy(bmz->graph);
+ return NULL;
+ }
+ // Ordering step
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Starting ordering step\n");
+ }
+ graph_obtain_critical_nodes(bmz->graph);
+
+ // Searching step
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Starting Searching step.\n");
+ fprintf(stderr, "\tTraversing critical vertices.\n");
+ }
+ DEBUGP("Searching step\n");
+ visited = (cmph_uint8 *)malloc((size_t)bmz->n/8 + 1);
+ memset(visited, 0, (size_t)bmz->n/8 + 1);
+ used_edges = (cmph_uint8 *)malloc((size_t)bmz->m/8 + 1);
+ memset(used_edges, 0, (size_t)bmz->m/8 + 1);
+ free(bmz->g);
+ bmz->g = (cmph_uint32 *)calloc((size_t)bmz->n, sizeof(cmph_uint32));
+ assert(bmz->g);
+ for (i = 0; i < bmz->n; ++i) // critical nodes
+ {
+ if (graph_node_is_critical(bmz->graph, i) && (!GETBIT(visited,i)))
+ {
+ if(c > 1.14) restart_mapping = bmz_traverse_critical_nodes(bmz, i, &biggest_g_value, &biggest_edge_value, used_edges, visited);
+ else restart_mapping = bmz_traverse_critical_nodes_heuristic(bmz, i, &biggest_g_value, &biggest_edge_value, used_edges, visited);
+ if(restart_mapping) break;
+ }
+ }
+ if(!restart_mapping)
+ {
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "\tTraversing non critical vertices.\n");
+ }
+ bmz_traverse_non_critical_nodes(bmz, used_edges, visited); // non_critical_nodes
+ }
+ else
+ {
+ iterations_map--;
+ if (mph->verbosity) fprintf(stderr, "Restarting mapping step. %u iterations remaining.\n", iterations_map);
+ }
+ free(used_edges);
+ free(visited);
+ }while(restart_mapping && iterations_map > 0);
+ graph_destroy(bmz->graph);
+ bmz->graph = NULL;
+ if (iterations_map == 0)
+ {
+ return NULL;
+ }
+ mphf = (cmph_t *)malloc(sizeof(cmph_t));
+ mphf->algo = mph->algo;
+ bmzf = (bmz_data_t *)malloc(sizeof(bmz_data_t));
+ bmzf->g = bmz->g;
+ bmz->g = NULL; //transfer memory ownership
+ bmzf->hashes = bmz->hashes;
+ bmz->hashes = NULL; //transfer memory ownership
+ bmzf->n = bmz->n;
+ bmzf->m = bmz->m;
+ mphf->data = bmzf;
+ mphf->size = bmz->m;
+
+ DEBUGP("Successfully generated minimal perfect hash\n");
+ if (mph->verbosity)
+ {
+ fprintf(stderr, "Successfully generated minimal perfect hash function\n");
+ }
+ return mphf;
+}
+
+static cmph_uint8 bmz_traverse_critical_nodes(bmz_config_data_t *bmz, cmph_uint32 v, cmph_uint32 * biggest_g_value, cmph_uint32 * biggest_edge_value, cmph_uint8 * used_edges, cmph_uint8 * visited)
+{
+ cmph_uint32 next_g;
+ cmph_uint32 u; /* Auxiliary vertex */
+ cmph_uint32 lav; /* lookahead vertex */
+ cmph_uint8 collision;
+ vqueue_t * q = vqueue_new((cmph_uint32)(graph_ncritical_nodes(bmz->graph)) + 1);
+ graph_iterator_t it, it1;
+
+ DEBUGP("Labelling critical vertices\n");
+ bmz->g[v] = (cmph_uint32)ceil ((double)(*biggest_edge_value)/2) - 1;
+ SETBIT(visited, v);
+ next_g = (cmph_uint32)floor((double)(*biggest_edge_value/2)); /* next_g is incremented in the do..while statement*/
+ vqueue_insert(q, v);
+ while(!vqueue_is_empty(q))
+ {
+ v = vqueue_remove(q);
+ it = graph_neighbors_it(bmz->graph, v);
+ while ((u = graph_next_neighbor(bmz->graph, &it)) != GRAPH_NO_NEIGHBOR)
+ {
+ if (graph_node_is_critical(bmz->graph, u) && (!GETBIT(visited,u)))
+ {
+ collision = 1;
+ while(collision) // lookahead to resolve collisions
+ {
+ next_g = *biggest_g_value + 1;
+ it1 = graph_neighbors_it(bmz->graph, u);
+ collision = 0;
+ while((lav = graph_next_neighbor(bmz->graph, &it1)) != GRAPH_NO_NEIGHBOR)
+ {
+ if (graph_node_is_critical(bmz->graph, lav) && GETBIT(visited,lav))
+ {
+ if(next_g + bmz->g[lav] >= bmz->m)
+ {
+ vqueue_destroy(q);
+ return 1; // restart mapping step.
+ }
+ if (GETBIT(used_edges, (next_g + bmz->g[lav])))
+ {
+ collision = 1;
+ break;
+ }
+ }
+ }
+ if (next_g > *biggest_g_value) *biggest_g_value = next_g;
+ }
+ // Marking used edges...
+ it1 = graph_neighbors_it(bmz->graph, u);
+ while((lav = graph_next_neighbor(bmz->graph, &it1)) != GRAPH_NO_NEIGHBOR)
+ {
+ if (graph_node_is_critical(bmz->graph, lav) && GETBIT(visited, lav))
+ {
+ SETBIT(used_edges,(next_g + bmz->g[lav]));
+ if(next_g + bmz->g[lav] > *biggest_edge_value) *biggest_edge_value = next_g + bmz->g[lav];
+ }
+ }
+ bmz->g[u] = next_g; // Labelling vertex u.
+ SETBIT(visited,u);
+ vqueue_insert(q, u);
+ }
+ }
+
+ }
+ vqueue_destroy(q);
+ return 0;
+}
+
+static cmph_uint8 bmz_traverse_critical_nodes_heuristic(bmz_config_data_t *bmz, cmph_uint32 v, cmph_uint32 * biggest_g_value, cmph_uint32 * biggest_edge_value, cmph_uint8 * used_edges, cmph_uint8 * visited)
+{
+ cmph_uint32 next_g;
+ cmph_uint32 u; /* Auxiliary vertex */
+ cmph_uint32 lav; /* lookahead vertex */
+ cmph_uint8 collision;
+ cmph_uint32 * unused_g_values = NULL;
+ cmph_uint32 unused_g_values_capacity = 0;
+ cmph_uint32 nunused_g_values = 0;
+ vqueue_t * q = vqueue_new((cmph_uint32)(0.5*graph_ncritical_nodes(bmz->graph))+1);
+ graph_iterator_t it, it1;
+
+ DEBUGP("Labelling critical vertices\n");
+ bmz->g[v] = (cmph_uint32)ceil ((double)(*biggest_edge_value)/2) - 1;
+ SETBIT(visited, v);
+ next_g = (cmph_uint32)floor((double)(*biggest_edge_value/2)); /* next_g is incremented in the do..while statement*/
+ vqueue_insert(q, v);
+ while(!vqueue_is_empty(q))
+ {
+ v = vqueue_remove(q);
+ it = graph_neighbors_it(bmz->graph, v);
+ while ((u = graph_next_neighbor(bmz->graph, &it)) != GRAPH_NO_NEIGHBOR)
+ {
+ if (graph_node_is_critical(bmz->graph, u) && (!GETBIT(visited,u)))
+ {
+ cmph_uint32 next_g_index = 0;
+ collision = 1;
+ while(collision) // lookahead to resolve collisions
+ {
+ if (next_g_index < nunused_g_values)
+ {
+ next_g = unused_g_values[next_g_index++];
+ }
+ else
+ {
+ next_g = *biggest_g_value + 1;
+ next_g_index = UINT_MAX;
+ }
+ it1 = graph_neighbors_it(bmz->graph, u);
+ collision = 0;
+ while((lav = graph_next_neighbor(bmz->graph, &it1)) != GRAPH_NO_NEIGHBOR)
+ {
+ if (graph_node_is_critical(bmz->graph, lav) && GETBIT(visited,lav))
+ {
+ if(next_g + bmz->g[lav] >= bmz->m)
+ {
+ vqueue_destroy(q);
+ free(unused_g_values);
+ return 1; // restart mapping step.
+ }
+ if (GETBIT(used_edges, (next_g + bmz->g[lav])))
+ {
+ collision = 1;
+ break;
+ }
+ }
+ }
+ if(collision && (next_g > *biggest_g_value)) // saving the current g value stored in next_g.
+ {
+ if(nunused_g_values == unused_g_values_capacity)
+ {
+ unused_g_values = (cmph_uint32 *)realloc(unused_g_values, (unused_g_values_capacity + BUFSIZ)*sizeof(cmph_uint32));
+ unused_g_values_capacity += BUFSIZ;
+ }
+ unused_g_values[nunused_g_values++] = next_g;
+
+ }
+ if (next_g > *biggest_g_value) *biggest_g_value = next_g;
+ }
+ next_g_index--;
+ if (next_g_index < nunused_g_values) unused_g_values[next_g_index] = unused_g_values[--nunused_g_values];
+
+ // Marking used edges...
+ it1 = graph_neighbors_it(bmz->graph, u);
+ while((lav = graph_next_neighbor(bmz->graph, &it1)) != GRAPH_NO_NEIGHBOR)
+ {
+ if (graph_node_is_critical(bmz->graph, lav) && GETBIT(visited, lav))
+ {
+ SETBIT(used_edges,(next_g + bmz->g[lav]));
+ if(next_g + bmz->g[lav] > *biggest_edge_value) *biggest_edge_value = next_g + bmz->g[lav];
+ }
+ }
+ bmz->g[u] = next_g; // Labelling vertex u.
+ SETBIT(visited, u);
+ vqueue_insert(q, u);
+ }
+ }
+
+ }
+ vqueue_destroy(q);
+ free(unused_g_values);
+ return 0;
+}
+
+static cmph_uint32 next_unused_edge(bmz_config_data_t *bmz, cmph_uint8 * used_edges, cmph_uint32 unused_edge_index)
+{
+ while(1)
+ {
+ assert(unused_edge_index < bmz->m);
+ if(GETBIT(used_edges, unused_edge_index)) unused_edge_index ++;
+ else break;
+ }
+ return unused_edge_index;
+}
+
+static void bmz_traverse(bmz_config_data_t *bmz, cmph_uint8 * used_edges, cmph_uint32 v, cmph_uint32 * unused_edge_index, cmph_uint8 * visited)
+{
+ graph_iterator_t it = graph_neighbors_it(bmz->graph, v);
+ cmph_uint32 neighbor = 0;
+ while((neighbor = graph_next_neighbor(bmz->graph, &it)) != GRAPH_NO_NEIGHBOR)
+ {
+ if(GETBIT(visited,neighbor)) continue;
+ //DEBUGP("Visiting neighbor %u\n", neighbor);
+ *unused_edge_index = next_unused_edge(bmz, used_edges, *unused_edge_index);
+ bmz->g[neighbor] = *unused_edge_index - bmz->g[v];
+ //if (bmz->g[neighbor] >= bmz->m) bmz->g[neighbor] += bmz->m;
+ SETBIT(visited, neighbor);
+ (*unused_edge_index)++;
+ bmz_traverse(bmz, used_edges, neighbor, unused_edge_index, visited);
+
+ }
+}
+
+static void bmz_traverse_non_critical_nodes(bmz_config_data_t *bmz, cmph_uint8 * used_edges, cmph_uint8 * visited)
+{
+
+ cmph_uint32 i, v1, v2, unused_edge_index = 0;
+ DEBUGP("Labelling non critical vertices\n");
+ for(i = 0; i < bmz->m; i++)
+ {
+ v1 = graph_vertex_id(bmz->graph, i, 0);
+ v2 = graph_vertex_id(bmz->graph, i, 1);
+ if((GETBIT(visited,v1) && GETBIT(visited,v2)) || (!GETBIT(visited,v1) && !GETBIT(visited,v2))) continue;
+ if(GETBIT(visited,v1)) bmz_traverse(bmz, used_edges, v1, &unused_edge_index, visited);
+ else bmz_traverse(bmz, used_edges, v2, &unused_edge_index, visited);
+
+ }
+
+ for(i = 0; i < bmz->n; i++)
+ {
+ if(!GETBIT(visited,i))
+ {
+ bmz->g[i] = 0;
+ SETBIT(visited, i);
+ bmz_traverse(bmz, used_edges, i, &unused_edge_index, visited);
+ }
+ }
+
+}
+
+static int bmz_gen_edges(cmph_config_t *mph)
+{
+ cmph_uint32 e;
+ bmz_config_data_t *bmz = (bmz_config_data_t *)mph->data;
+ cmph_uint8 multiple_edges = 0;
+ DEBUGP("Generating edges for %u vertices\n", bmz->n);
+ graph_clear_edges(bmz->graph);
+ mph->key_source->rewind(mph->key_source->data);
+ for (e = 0; e < mph->key_source->nkeys; ++e)
+ {
+ cmph_uint32 h1, h2;
+ cmph_uint32 keylen;
+ char *key = NULL;
+ mph->key_source->read(mph->key_source->data, &key, &keylen);
+
+// if (key == NULL)fprintf(stderr, "key = %s -- read BMZ\n", key);
+ h1 = hash(bmz->hashes[0], key, keylen) % bmz->n;
+ h2 = hash(bmz->hashes[1], key, keylen) % bmz->n;
+ if (h1 == h2) if (++h2 >= bmz->n) h2 = 0;
+ if (h1 == h2)
+ {
+ if (mph->verbosity) fprintf(stderr, "Self loop for key %u\n", e);
+ mph->key_source->dispose(mph->key_source->data, key, keylen);
+ return 0;
+ }
+ //DEBUGP("Adding edge: %u -> %u for key %s\n", h1, h2, key);
+ mph->key_source->dispose(mph->key_source->data, key, keylen);
+// fprintf(stderr, "key = %s -- dispose BMZ\n", key);
+ multiple_edges = graph_contains_edge(bmz->graph, h1, h2);
+ if (mph->verbosity && multiple_edges) fprintf(stderr, "A non simple graph was generated\n");
+ if (multiple_edges) return 0; // checking multiple edge restriction.
+ graph_add_edge(bmz->graph, h1, h2);
+ }
+ return !multiple_edges;
+}
+
+int bmz_dump(cmph_t *mphf, FILE *fd)
+{
+ char *buf = NULL;
+ cmph_uint32 buflen;
+ cmph_uint32 two = 2; //number of hash functions
+ bmz_data_t *data = (bmz_data_t *)mphf->data;
+ register size_t nbytes;
+ __cmph_dump(mphf, fd);
+
+ nbytes = fwrite(&two, sizeof(cmph_uint32), (size_t)1, fd);
+
+ hash_state_dump(data->hashes[0], &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->hashes[1], &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->n), sizeof(cmph_uint32), (size_t)1, fd);
+ nbytes = fwrite(&(data->m), sizeof(cmph_uint32), (size_t)1, fd);
+
+ nbytes = fwrite(data->g, sizeof(cmph_uint32)*(data->n), (size_t)1, fd);
+ #ifdef DEBUG
+ cmph_uint32 i;
+ fprintf(stderr, "G: ");
+ for (i = 0; i < data->n; ++i) fprintf(stderr, "%u ", data->g[i]);
+ fprintf(stderr, "\n");
+ #endif
+ return 1;
+}
+
+void bmz_load(FILE *f, cmph_t *mphf)
+{
+ cmph_uint32 nhashes;
+ char *buf = NULL;
+ cmph_uint32 buflen;
+ cmph_uint32 i;
+ bmz_data_t *bmz = (bmz_data_t *)malloc(sizeof(bmz_data_t));
+ register size_t nbytes;
+ DEBUGP("Loading bmz mphf\n");
+ mphf->data = bmz;
+ nbytes = fread(&nhashes, sizeof(cmph_uint32), (size_t)1, f);
+ bmz->hashes = (hash_state_t **)malloc(sizeof(hash_state_t *)*(nhashes + 1));
+ bmz->hashes[nhashes] = NULL;
+ DEBUGP("Reading %u hashes\n", nhashes);
+ for (i = 0; i < nhashes; ++i)
+ {
+ hash_state_t *state = NULL;
+ nbytes = fread(&buflen, sizeof(cmph_uint32), (size_t)1, f);
+ DEBUGP("Hash state has %u bytes\n", buflen);
+ buf = (char *)malloc((size_t)buflen);
+ nbytes = fread(buf, (size_t)buflen, (size_t)1, f);
+ state = hash_state_load(buf, buflen);
+ bmz->hashes[i] = state;
+ free(buf);
+ }
+
+ DEBUGP("Reading m and n\n");
+ nbytes = fread(&(bmz->n), sizeof(cmph_uint32), (size_t)1, f);
+ nbytes = fread(&(bmz->m), sizeof(cmph_uint32), (size_t)1, f);
+
+ bmz->g = (cmph_uint32 *)malloc(sizeof(cmph_uint32)*bmz->n);
+ nbytes = fread(bmz->g, bmz->n*sizeof(cmph_uint32), (size_t)1, f);
+ #ifdef DEBUG
+ fprintf(stderr, "G: ");
+ for (i = 0; i < bmz->n; ++i) fprintf(stderr, "%u ", bmz->g[i]);
+ fprintf(stderr, "\n");
+ #endif
+ return;
+}
+
+
+cmph_uint32 bmz_search(cmph_t *mphf, const char *key, cmph_uint32 keylen)
+{
+ bmz_data_t *bmz = mphf->data;
+ cmph_uint32 h1 = hash(bmz->hashes[0], key, keylen) % bmz->n;
+ cmph_uint32 h2 = hash(bmz->hashes[1], key, keylen) % bmz->n;
+ DEBUGP("key: %s h1: %u h2: %u\n", key, h1, h2);
+ if (h1 == h2 && ++h2 > bmz->n) h2 = 0;
+ DEBUGP("key: %s g[h1]: %u g[h2]: %u edges: %u\n", key, bmz->g[h1], bmz->g[h2], bmz->m);
+ return bmz->g[h1] + bmz->g[h2];
+}
+void bmz_destroy(cmph_t *mphf)
+{
+ bmz_data_t *data = (bmz_data_t *)mphf->data;
+ free(data->g);
+ hash_state_destroy(data->hashes[0]);
+ hash_state_destroy(data->hashes[1]);
+ free(data->hashes);
+ free(data);
+ free(mphf);
+}
+
+/** \fn void bmz_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 bmz_pack(cmph_t *mphf, void *packed_mphf)
+{
+
+ bmz_data_t *data = (bmz_data_t *)mphf->data;
+ cmph_uint8 * ptr = packed_mphf;
+
+ // packing h1 type
+ CMPH_HASH h1_type = hash_get_type(data->hashes[0]);
+ *((cmph_uint32 *) ptr) = h1_type;
+ ptr += sizeof(cmph_uint32);
+
+ // packing h1
+ hash_state_pack(data->hashes[0], ptr);
+ ptr += hash_state_packed_size(h1_type);
+
+ // packing h2 type
+ CMPH_HASH h2_type = hash_get_type(data->hashes[1]);
+ *((cmph_uint32 *) ptr) = h2_type;
+ ptr += sizeof(cmph_uint32);
+
+ // packing h2
+ hash_state_pack(data->hashes[1], ptr);
+ ptr += hash_state_packed_size(h2_type);
+
+ // packing n
+ *((cmph_uint32 *) ptr) = data->n;
+ ptr += sizeof(data->n);
+
+ // packing g
+ memcpy(ptr, data->g, sizeof(cmph_uint32)*data->n);
+}
+
+/** \fn cmph_uint32 bmz_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 bmz_packed_size(cmph_t *mphf)
+{
+ bmz_data_t *data = (bmz_data_t *)mphf->data;
+ CMPH_HASH h1_type = hash_get_type(data->hashes[0]);
+ CMPH_HASH h2_type = hash_get_type(data->hashes[1]);
+
+ return (cmph_uint32)(sizeof(CMPH_ALGO) + hash_state_packed_size(h1_type) + hash_state_packed_size(h2_type) +
+ 3*sizeof(cmph_uint32) + sizeof(cmph_uint32)*data->n);
+}
+
+/** cmph_uint32 bmz_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 bmz_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 n = *g_ptr++;
+
+ register cmph_uint32 h1 = hash_packed(h1_ptr, h1_type, key, keylen) % n;
+ register cmph_uint32 h2 = hash_packed(h2_ptr, h2_type, key, keylen) % n;
+ if (h1 == h2 && ++h2 > n) h2 = 0;
+ return (g_ptr[h1] + g_ptr[h2]);
+}
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