*** empty log message ***

examples/Makefile.am

@@ -1,4 +1,4 @@
-noinst_PROGRAMS = vector_adapter_ex1 file_adapter_ex2
+noinst_PROGRAMS = vector_adapter_ex1 file_adapter_ex2 struct_vector_adapter_ex3
 
 INCLUDES = -I../src/
 
@@ -8,3 +8,5 @@ vector_adapter_ex1_SOURCES = vector_adapter_ex1.c
 file_adapter_ex2_LDADD     = ../src/libcmph.la
 file_adapter_ex2_SOURCES   = file_adapter_ex2.c
 
+struct_vector_adapter_ex3_LDADD     = ../src/libcmph.la
+struct_vector_adapter_ex3_SOURCES   = struct_vector_adapter_ex3.c

examples/struct_vector_adapter_ex3.c

@@ -0,0 +1,52 @@
+#include <cmph.h>
+#include <string.h>
+// Create minimal perfect hash function from in-memory vector
+
+#pragma pack(1)
+typedef struct {
+	cmph_uint32 id;
+	char key[11];
+	cmph_uint32 year;
+} rec_t;
+#pragma pack(0)
+
+int main(int argc, char **argv)
+{   
+	// Creating a filled vector
+    unsigned int i = 0;  
+    rec_t vector[10] = {{1, "aaaaaaaaaa", 1999}, {2, "bbbbbbbbbb", 2000}, {3, "cccccccccc", 2001},
+    					{4, "dddddddddd", 2002}, {5, "eeeeeeeeee", 2003}, {6, "ffffffffff", 2004},
+    					{7, "gggggggggg", 2005}, {8, "hhhhhhhhhh", 2006}, {9, "iiiiiiiiii", 2007},
+    					{10,"jjjjjjjjjj", 2008}};
+	unsigned int nkeys = 10;
+    FILE* mphf_fd = fopen("temp_struct_vector.mph", "w");
+	// Source of keys
+    fprintf(stderr, "sizeof(rec_t) -> %ld\n", sizeof(rec_t));
+	cmph_io_adapter_t *source = cmph_io_struct_vector_adapter(vector, sizeof(rec_t), sizeof(cmph_uint32), 11, nkeys); 
+
+	//Create minimal perfect hash function using the default (chm) algorithm.
+	cmph_config_t *config = cmph_config_new(source);
+	cmph_config_set_algo(config, CMPH_BDZ);
+	cmph_config_set_mphf_fd(config, mphf_fd);
+	cmph_t *hash = cmph_new(config);
+	cmph_config_destroy(config);
+    cmph_dump(hash, mphf_fd); 
+	cmph_destroy(hash);	
+	fclose(mphf_fd);
+   
+	//Find key
+    mphf_fd = fopen("temp_struct_vector.mph", "r");
+    hash = cmph_load(mphf_fd);
+    while (i < nkeys) {
+       const char *key = vector[i].key;
+	   unsigned int id = cmph_search(hash, key, 11);
+	   fprintf(stderr, "key:%s -- hash:%u\n", key, id);
+       i++;
+    }
+    
+	//Destroy hash
+	cmph_destroy(hash);
+	cmph_io_vector_adapter_destroy(source);   
+    fclose(mphf_fd);
+	return 0;
+}

src/cmph.c

@@ -23,9 +23,35 @@ typedef struct
 	cmph_uint32 position; // access position when data is a vector	
 } cmph_vector_t;
 
+
+
+/** 
+ * Support a vector of struct as the source of keys.
+ *
+ * E.g. The keys could be the fieldB's in a vector of struct rec where 
+ * struct rec is defined as:
+ * struct rec {
+ *    fieldA;
+ *    fieldB;
+ *    fieldC;
+ * }
+ */
+typedef struct 
+{
+	void *vector;					/* Pointer to the vector of struct */
+	cmph_uint32 position; 			/* current position */
+	cmph_uint32 struct_size;       	/* The size of the struct */
+	cmph_uint32 key_offset;        	/* The byte offset of the key in the struct */
+	cmph_uint32 key_len;          	/* The length of the key */
+} cmph_struct_vector_t;
+
+
 static cmph_io_adapter_t *cmph_io_vector_new(void * vector, cmph_uint32 nkeys);
 static void cmph_io_vector_destroy(cmph_io_adapter_t * key_source);
 
+static cmph_io_adapter_t *cmph_io_struct_vector_new(void * vector, cmph_uint32 struct_size, cmph_uint32 key_offset, cmph_uint32 key_len, cmph_uint32 nkeys);
+static void cmph_io_struct_vector_destroy(cmph_io_adapter_t * key_source);
+
 static int key_nlfile_read(void *data, char **key, cmph_uint32 *keylen)
 {
 	FILE *fd = (FILE *)data;
@@ -63,6 +89,17 @@ static int key_byte_vector_read(void *data, char **key, cmph_uint32 *keylen)
 
 }
 
+static int key_struct_vector_read(void *data, char **key, cmph_uint32 *keylen)
+{
+    cmph_struct_vector_t *cmph_struct_vector = (cmph_struct_vector_t *)data;
+    char *keys_vd = (char *)cmph_struct_vector->vector;
+    *keylen = cmph_struct_vector->key_len;
+    *key = (char *)malloc(*keylen);
+	memcpy(*key, (keys_vd + (cmph_struct_vector->position * cmph_struct_vector->struct_size) + cmph_struct_vector->key_offset), *keylen);
+	cmph_struct_vector->position = cmph_struct_vector->position + 1;
+	return *keylen;
+}
+
 static int key_vector_read(void *data, char **key, cmph_uint32 *keylen)
 {
         cmph_vector_t *cmph_vector = (cmph_vector_t *)data;
@@ -92,6 +129,12 @@ static void key_nlfile_rewind(void *data)
 	rewind(fd);
 }
 
+static void key_struct_vector_rewind(void *data)
+{
+	cmph_struct_vector_t *cmph_struct_vector = (cmph_struct_vector_t *)data;
+	cmph_struct_vector->position = 0;
+}
+
 static void key_vector_rewind(void *data)
 {
 	cmph_vector_t *cmph_vector = (cmph_vector_t *)data;
@@ -148,6 +191,31 @@ void cmph_io_nlnkfile_adapter_destroy(cmph_io_adapter_t * key_source)
 	free(key_source);
 }
 
+
+static cmph_io_adapter_t *cmph_io_struct_vector_new(void * vector, cmph_uint32 struct_size, cmph_uint32 key_offset, cmph_uint32 key_len, cmph_uint32 nkeys)
+{
+	cmph_io_adapter_t * key_source = (cmph_io_adapter_t *)malloc(sizeof(cmph_io_adapter_t));
+	cmph_struct_vector_t * cmph_struct_vector = (cmph_struct_vector_t *)malloc(sizeof(cmph_struct_vector_t));
+	assert(key_source);
+	assert(cmph_struct_vector);
+	cmph_struct_vector->vector = vector;
+	cmph_struct_vector->position = 0;
+	cmph_struct_vector->struct_size = struct_size;
+	cmph_struct_vector->key_offset = key_offset;
+	cmph_struct_vector->key_len = key_len;
+	key_source->data = (void *)cmph_struct_vector;
+	key_source->nkeys = nkeys;
+	return key_source;
+}
+
+static void cmph_io_struct_vector_destroy(cmph_io_adapter_t * key_source)
+{
+	cmph_struct_vector_t *cmph_struct_vector = (cmph_struct_vector_t *)key_source->data;
+	cmph_struct_vector->vector = NULL;
+	free(cmph_struct_vector);
+	free(key_source);
+}
+
 static cmph_io_adapter_t *cmph_io_vector_new(void * vector, cmph_uint32 nkeys)
 {
 	cmph_io_adapter_t * key_source = (cmph_io_adapter_t *)malloc(sizeof(cmph_io_adapter_t));
@@ -181,6 +249,21 @@ void cmph_io_byte_vector_adapter_destroy(cmph_io_adapter_t * key_source)
 {
 	cmph_io_vector_destroy(key_source);
 }
+
+cmph_io_adapter_t *cmph_io_struct_vector_adapter(void * vector, cmph_uint32 struct_size, cmph_uint32 key_offset, cmph_uint32 key_len, cmph_uint32 nkeys)
+{
+	cmph_io_adapter_t * key_source = cmph_io_struct_vector_new(vector, struct_size, key_offset, key_len, nkeys);
+	key_source->read = key_struct_vector_read;
+	key_source->dispose = key_vector_dispose;
+	key_source->rewind = key_struct_vector_rewind;
+	return key_source;	
+}
+
+void cmph_io_struct_vector_adapter_destroy(cmph_io_adapter_t * key_source)
+{
+	cmph_io_struct_vector_destroy(key_source);	
+}
+
 cmph_io_adapter_t *cmph_io_vector_adapter(char ** vector, cmph_uint32 nkeys)
 {
 	cmph_io_adapter_t * key_source = cmph_io_vector_new(vector, nkeys);

src/cmph.h

@@ -37,6 +37,9 @@ void cmph_io_vector_adapter_destroy(cmph_io_adapter_t * key_source);
 cmph_io_adapter_t *cmph_io_byte_vector_adapter(cmph_uint8 ** vector, cmph_uint32 nkeys);
 void cmph_io_byte_vector_adapter_destroy(cmph_io_adapter_t * key_source);
 
+cmph_io_adapter_t *cmph_io_struct_vector_adapter(void * vector, cmph_uint32 struct_size, cmph_uint32 key_offset, cmph_uint32 key_len, cmph_uint32 nkeys);
+void cmph_io_struct_vector_adapter_destroy(cmph_io_adapter_t * key_source);
+
 /** Hash configuration API **/
 cmph_config_t *cmph_config_new(cmph_io_adapter_t *key_source);
 void cmph_config_set_hashfuncs(cmph_config_t *mph, CMPH_HASH *hashfuncs);