1 files changed, 381 insertions, 0 deletions
diff --git a/girepository/cmph/chm.c b/girepository/cmph/chm.c
new file mode 100644
index 00000000..e03cca80
--- /dev/null
+++ b/girepository/cmph/chm.c
@@ -0,0 +1,381 @@
+#include "graph.h"
+#include "chm.h"
+#include "cmph_structs.h"
+#include "chm_structs.h"
+#include "hash.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 chm_gen_edges(cmph_config_t *mph);
+static void chm_traverse(chm_config_data_t *chm, cmph_uint8 *visited, cmph_uint32 v);
+
+chm_config_data_t *chm_config_new()
+{
+	chm_config_data_t *chm = NULL;
+	chm = (chm_config_data_t *)malloc(sizeof(chm_config_data_t));
+	assert(chm);
+	memset(chm, 0, sizeof(chm_config_data_t));
+	chm->hashfuncs[0] = CMPH_HASH_JENKINS;
+	chm->hashfuncs[1] = CMPH_HASH_JENKINS;
+	chm->g = NULL;
+	chm->graph = NULL;
+	chm->hashes = NULL;
+	return chm;
+}
+void chm_config_destroy(cmph_config_t *mph)
+{
+	chm_config_data_t *data = (chm_config_data_t *)mph->data;
+	DEBUGP("Destroying algorithm dependent data\n");
+	free(data);
+}
+
+void chm_config_set_hashfuncs(cmph_config_t *mph, CMPH_HASH *hashfuncs)
+{
+	chm_config_data_t *chm = (chm_config_data_t *)mph->data;
+	CMPH_HASH *hashptr = hashfuncs;
+	cmph_uint32 i = 0;
+	while(*hashptr != CMPH_HASH_COUNT)
+	{
+		if (i >= 2) break; //chm only uses two hash functions
+		chm->hashfuncs[i] = *hashptr;	
+		++i, ++hashptr;
+	}
+}
+
+cmph_t *chm_new(cmph_config_t *mph, double c)
+{
+	cmph_t *mphf = NULL;
+	chm_data_t *chmf = NULL;
+
+	cmph_uint32 i;
+	cmph_uint32 iterations = 20;
+	cmph_uint8 *visited = NULL;
+	chm_config_data_t *chm = (chm_config_data_t *)mph->data;
+	chm->m = mph->key_source->nkeys;
+	if (c == 0) c = 2.09;
+	chm->n = (cmph_uint32)ceil(c * mph->key_source->nkeys);	
+	DEBUGP("m (edges): %u n (vertices): %u c: %f\n", chm->m, chm->n, c);
+	chm->graph = graph_new(chm->n, chm->m);
+	DEBUGP("Created graph\n");
+
+	chm->hashes = (hash_state_t **)malloc(sizeof(hash_state_t *)*3);
+	for(i = 0; i < 3; ++i) chm->hashes[i] = NULL;
+	//Mapping step
+	if (mph->verbosity)
+	{
+		fprintf(stderr, "Entering mapping step for mph creation of %u keys with graph sized %u\n", chm->m, chm->n);
+	}
+	while(1)
+	{
+		int ok;
+		chm->hashes[0] = hash_state_new(chm->hashfuncs[0], chm->n);
+		chm->hashes[1] = hash_state_new(chm->hashfuncs[1], chm->n);
+		ok = chm_gen_edges(mph);
+		if (!ok)
+		{
+			--iterations;
+			hash_state_destroy(chm->hashes[0]);
+			chm->hashes[0] = NULL;
+			hash_state_destroy(chm->hashes[1]);
+			chm->hashes[1] = NULL;
+			DEBUGP("%u iterations remaining\n", iterations);
+			if (mph->verbosity)
+			{
+				fprintf(stderr, "Acyclic graph creation failure - %u iterations remaining\n", iterations);
+			}
+			if (iterations == 0) break;
+		} 
+		else break;	
+	}
+	if (iterations == 0)
+	{
+		graph_destroy(chm->graph);	
+		return NULL;
+	}
+
+	//Assignment step
+	if (mph->verbosity)
+	{
+		fprintf(stderr, "Starting assignment step\n");
+	}
+	DEBUGP("Assignment step\n");
+ 	visited = (cmph_uint8 *)malloc((size_t)(chm->n/8 + 1));
+	memset(visited, 0, (size_t)(chm->n/8 + 1));
+	free(chm->g);
+	chm->g = (cmph_uint32 *)malloc(chm->n * sizeof(cmph_uint32));
+	assert(chm->g);
+	for (i = 0; i < chm->n; ++i)
+	{
+	        if (!GETBIT(visited,i))
+		{
+			chm->g[i] = 0;
+			chm_traverse(chm, visited, i);
+		}
+	}
+	graph_destroy(chm->graph);	
+	free(visited);
+	chm->graph = NULL;
+
+	mphf = (cmph_t *)malloc(sizeof(cmph_t));
+	mphf->algo = mph->algo;
+	chmf = (chm_data_t *)malloc(sizeof(chm_data_t));
+	chmf->g = chm->g;
+	chm->g = NULL; //transfer memory ownership
+	chmf->hashes = chm->hashes;
+	chm->hashes = NULL; //transfer memory ownership
+	chmf->n = chm->n;
+	chmf->m = chm->m;
+	mphf->data = chmf;
+	mphf->size = chm->m;
+	DEBUGP("Successfully generated minimal perfect hash\n");
+	if (mph->verbosity)
+	{
+		fprintf(stderr, "Successfully generated minimal perfect hash function\n");
+	}
+	return mphf;
+}
+
+static void chm_traverse(chm_config_data_t *chm, cmph_uint8 *visited, cmph_uint32 v)
+{
+
+	graph_iterator_t it = graph_neighbors_it(chm->graph, v);
+	cmph_uint32 neighbor = 0;
+	SETBIT(visited,v);
+	
+	DEBUGP("Visiting vertex %u\n", v);
+	while((neighbor = graph_next_neighbor(chm->graph, &it)) != GRAPH_NO_NEIGHBOR)
+	{
+		DEBUGP("Visiting neighbor %u\n", neighbor);
+		if(GETBIT(visited,neighbor)) continue;
+		DEBUGP("Visiting neighbor %u\n", neighbor);
+		DEBUGP("Visiting edge %u->%u with id %u\n", v, neighbor, graph_edge_id(chm->graph, v, neighbor));
+		chm->g[neighbor] = graph_edge_id(chm->graph, v, neighbor) - chm->g[v];
+		DEBUGP("g is %u (%u - %u mod %u)\n", chm->g[neighbor], graph_edge_id(chm->graph, v, neighbor), chm->g[v], chm->m);
+		chm_traverse(chm, visited, neighbor);
+	}
+}
+		
+static int chm_gen_edges(cmph_config_t *mph)
+{
+	cmph_uint32 e;
+	chm_config_data_t *chm = (chm_config_data_t *)mph->data;
+	int cycles = 0;
+
+	DEBUGP("Generating edges for %u vertices with hash functions %s and %s\n", chm->n, cmph_hash_names[chm->hashfuncs[0]], cmph_hash_names[chm->hashfuncs[1]]);
+	graph_clear_edges(chm->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;
+		mph->key_source->read(mph->key_source->data, &key, &keylen);
+		h1 = hash(chm->hashes[0], key, keylen) % chm->n;
+		h2 = hash(chm->hashes[1], key, keylen) % chm->n;
+		if (h1 == h2) if (++h2 >= chm->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);
+		graph_add_edge(chm->graph, h1, h2);
+	}
+	cycles = graph_is_cyclic(chm->graph);
+	if (mph->verbosity && cycles) fprintf(stderr, "Cyclic graph generated\n");
+	DEBUGP("Looking for cycles: %u\n", cycles);
+
+	return ! cycles;
+}
+
+int chm_dump(cmph_t *mphf, FILE *fd)
+{
+	char *buf = NULL;
+	cmph_uint32 buflen;
+	cmph_uint32 two = 2; //number of hash functions
+	chm_data_t *data = (chm_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
+	fprintf(stderr, "G: ");
+	for (i = 0; i < data->n; ++i) fprintf(stderr, "%u ", data->g[i]);
+	fprintf(stderr, "\n");
+	#endif*/
+	return 1;
+}
+
+void chm_load(FILE *f, cmph_t *mphf)
+{
+	cmph_uint32 nhashes;
+	char *buf = NULL;
+	cmph_uint32 buflen;
+	cmph_uint32 i;
+	chm_data_t *chm = (chm_data_t *)malloc(sizeof(chm_data_t));
+	register size_t nbytes;
+	DEBUGP("Loading chm mphf\n");
+	mphf->data = chm;
+	nbytes = fread(&nhashes, sizeof(cmph_uint32), (size_t)1, f);
+	chm->hashes = (hash_state_t **)malloc(sizeof(hash_state_t *)*(nhashes + 1));
+	chm->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);
+		chm->hashes[i] = state;
+		free(buf);
+	}
+
+	DEBUGP("Reading m and n\n");
+	nbytes = fread(&(chm->n), sizeof(cmph_uint32), (size_t)1, f);	
+	nbytes = fread(&(chm->m), sizeof(cmph_uint32), (size_t)1, f);	
+
+	chm->g = (cmph_uint32 *)malloc(sizeof(cmph_uint32)*chm->n);
+	nbytes = fread(chm->g, chm->n*sizeof(cmph_uint32), (size_t)1, f);
+	#ifdef DEBUG
+	fprintf(stderr, "G: ");
+	for (i = 0; i < chm->n; ++i) fprintf(stderr, "%u ", chm->g[i]);
+	fprintf(stderr, "\n");
+	#endif
+	return;
+}
+		
+
+cmph_uint32 chm_search(cmph_t *mphf, const char *key, cmph_uint32 keylen)
+{
+	chm_data_t *chm = mphf->data;
+	cmph_uint32 h1 = hash(chm->hashes[0], key, keylen) % chm->n;
+	cmph_uint32 h2 = hash(chm->hashes[1], key, keylen) % chm->n;
+	DEBUGP("key: %s h1: %u h2: %u\n", key, h1, h2);
+	if (h1 == h2 && ++h2 >= chm->n) h2 = 0;
+	DEBUGP("key: %s g[h1]: %u g[h2]: %u edges: %u\n", key, chm->g[h1], chm->g[h2], chm->m);
+	return (chm->g[h1] + chm->g[h2]) % chm->m;
+}
+void chm_destroy(cmph_t *mphf)
+{
+	chm_data_t *data = (chm_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 chm_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 chm_pack(cmph_t *mphf, void *packed_mphf)
+{
+	chm_data_t *data = (chm_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 m
+	*((cmph_uint32 *) ptr) = data->m;
+	ptr += sizeof(data->m);
+
+	// packing g
+	memcpy(ptr, data->g, sizeof(cmph_uint32)*data->n);	
+}
+
+/** \fn cmph_uint32 chm_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 chm_packed_size(cmph_t *mphf)
+{
+	chm_data_t *data = (chm_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) + 
+			4*sizeof(cmph_uint32) + sizeof(cmph_uint32)*data->n);
+}
+
+/** cmph_uint32 chm_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 chm_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 m = *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; 
+	DEBUGP("key: %s h1: %u h2: %u\n", key, h1, h2);
+	if (h1 == h2 && ++h2 >= n) h2 = 0;
+	DEBUGP("key: %s g[h1]: %u g[h2]: %u edges: %u\n", key, g_ptr[h1], g_ptr[h2], m);
+	return (g_ptr[h1] + g_ptr[h2]) % m;	
+}