#ifndef STON_FUNC
#define STON_FUNC STON_FUNC_STATIC STON_FUNC_INLINE
#endif //STON_FUNC
-#ifndef STON_NOSTDIO
+#ifdef STON_HT_FREAD
#include <stdio.h>
-#include <string.h> //memcpy
+#include <errno.h>
#include <alloca.h>
-#endif //STON_NOSTDIO
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+ston_ht ston_ht32_fread(FILE*,long,void*(*)(size_t));
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+size_t ston_ht32_fwrite(ston_ht,FILE*,long);
+#else
+#include <stddef.h>
+#endif //STON_HT_FREAD
#include <stdint.h>
+#include <string.h> //mem*
/* STON Hashtable Structure
Hashtables are stored as dynamically sized two dimensional arrays
*/
typedef struct ston_ht_header_t
{ uint16_t ht_columns;
uint8_t ht_2pow, ht_flags;
-}* ston_ht;
+}ston_ht_h,* ston_ht;
STON_FUNC
-size_t ston_up2pow(size_t);
-STON_FUNC_STATIC
-STON_FUNC_NOINLINE
-ston_ht ston_ht32_fread(FILE*,long,void*(*)(size_t));
+uint32_t ston_up2pow(uint32_t);
+STON_FUNC
+uint8_t ston_trailing0(uint32_t);
STON_FUNC
-ston_ht ston_ht32_create(uint16_t,size_t,uint8_t,void*(*)(size_t));
+ston_ht ston_ht32_create(uint16_t,uint8_t,uint8_t,void*(*)(size_t));
STON_FUNC
uint32_t* ston_ht32_row(ston_ht,uint32_t);
STON_FUNC
uint32_t ston_ht32_insert(ston_ht,uint32_t,uint16_t,uint32_t);
+STON_FUNC
+size_t ston_ht32_insertx(ston_ht,uint32_t,uint32_t*,size_t,size_t);
-#define ston_ht32_new(_COL,_N,_FN) ston_ht32_create(_COLS,ston_up2pow(_N << 1),0,_FN)
-#define ston_ht32_col(_HT,_KEY,_COL) (ston_ht32_row(_HT,_KEY) + _COL)
-#define ston_ht32_insertx(_HT,_KEY,_COL,_VAL) *ston_ht32_col(_HT,_KEY,_COL) = _VAL
+#define ston_ht32_new(_COL,_N,_F,_FN) (ston_ht32_create(_COL,ston_trailing0(ston_up2pow(_N << 1)),_F,_FN))
+#define ston_ht32_entry(_HT,_KEY,_COL) (ston_ht32_row(_HT,_KEY) + _COL)
#define ston_ht_size(_HT) ((_HT)->ht_columns << (_HT)->ht_2pow)
#define ston_ht_rows(_HT) (0x1 << (_HT)->ht_2pow)
#define ston_ht_cols(_HT) ((_HT)->ht_columns)
-#define ston_ht_start(_HT) (((uint8_t*)(_HT)) + sizeof(*(_HT)))
+#define ston_ht_start(_HT) ((uint8_t*)((_HT) + 1))
#define ston_ht_keyrow(_HT,_KEY) ((_KEY) & (ston_ht_rows(ht) - 1))
#define ston_ht32_start(_HT) ((uint32_t*)ston_ht_start(_HT))
+#define ston_ht32_end(_HT) (ston_ht32_start(_HT) + ston_ht_size(_HT))
#define ston_ht32_size(_HT) (ston_ht_size(_HT) * sizeof(uint32_t))
/** @see http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2 */
STON_FUNC
-size_t ston_up2pow
-( size_t val )
+uint32_t ston_up2pow
+( uint32_t val )
{ val = (val << 1) - 1;
val |= val >> 1;
val |= val >> 2;
return ++val;
}
+/** @see https://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightParallel */
+STON_FUNC
+uint8_t ston_trailing0
+( uint32_t v )
+{ uint8_t c = 32;
+ v &= -(int32_t)v;
+ if (v) c--;
+ if (v & 0x0000FFFF) c -= 16;
+ if (v & 0x00FF00FF) c -= 8;
+ if (v & 0x0F0F0F0F) c -= 4;
+ if (v & 0x33333333) c -= 2;
+ if (v & 0x55555555) c -= 1;
+ return c;
+}
+
/* Creates a new hash table, provided a memory allocation function that takes a
- single size_t bytes, a column count, and a row count which estimates the
- number of unique keys held in the table. The provided ht_rows is doubled,
- and rounded up to the nearest power of two to create a hash table with
- minimal collisions.
+ single size_t bytes, a column count, and a row count which determines the
+ size of the table.
+
+ use ston_ht32_new to specify the exact or estimated number of unique keys
+ held in the table. With ston_ht32_new, the provided ht_rows is doubled, and
+ rounded up to the nearest power of two to create a hash table with minimal
+ collisions.
*/
STON_FUNC
ston_ht ston_ht32_create
( uint16_t ht_columns,
- size_t ht_rows,
+ uint8_t ht_2pow,
uint8_t ht_flags,
void* (*alloc_fn)(size_t)
)
-{ size_t ht_size = ston_up2pow(ht_rows << 1) * ht_columns * sizeof(uint32_t);
- ston_ht ht = (ston_ht) alloc_fn(sizeof(struct ston_ht_header_t) + ht_size);
+{ size_t ht_bytes = (ht_columns << ht_2pow) * sizeof(uint32_t);
+ ston_ht ht = (ston_ht) alloc_fn(sizeof(ston_ht_h) + ht_bytes);
if (ht != NULL)
- { for (ht->ht_2pow = 0; ht_size; ht->ht_2pow++)
- ht_size = ht_size >> 1;
- ht->ht_columns = ht_columns;
+ { ht->ht_columns = ht_columns;
+ ht->ht_2pow = ht_2pow;
ht->ht_flags = ht_flags;
+ memset(ht + 1, 0, ht_bytes);
}
return ht;
}
-#ifndef STON_NO_STDIO
+#ifdef STON_HT_FREAD
/* Reads a 32-bit hash table out of the provided file at the provide fpos, into
a buffer allocated by alloc_fn. Memory is allocated to the stack until the
entire structure is verified, and all file operations are finished.
ston_ht stack_ht, ht;
long fpos_start;
size_t table_size, alloc_size;
+ int errno_local;
if ((fpos_start = ftell(file)) == -1)
return NULL;
if (fread(&header, sizeof(header), 1, file) != 1)
- return NULL;
+ goto fail_seekback;
table_size = ston_ht32_size(&header);
alloc_size = sizeof(header) + table_size;
stack_ht = (ston_ht) alloca(alloc_size);
memcpy(stack_ht, &header, sizeof(header));
if (fread(stack_ht + sizeof(header), table_size, 1, file) != 1)
- return NULL;
+ goto fail_seekback;
if (fseek(file, fpos_start, SEEK_SET) != 0)
return NULL;
ht = (ston_ht) alloc_fn(alloc_size);
if (ht != NULL)
memcpy(ht, stack_ht, alloc_size);
return ht;
+ fail_seekback:
+ /* Try to seek the file back to origin without clobbering errno */
+ errno_local = errno;
+ fseek(file, fpos_start, SEEK_SET);
+ errno = errno_local;
+ return NULL;
+}
+
+/* Writes a 32-bit hash table from memory into a file at fpos. Returns the
+ number of bytes written to the file, errno is set on error. */
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+size_t ston_ht32_fwrite
+( struct ston_ht_header_t* ht,
+ FILE* file,
+ long fpos
+)
+{ size_t bytes_written;
+ long fpos_start;
+ if ((fpos_start = ftell(file)) == NULL
+ || fseek(file, fpos, SEEK_SET) == 0
+ || (bytes_written = fwrite(file, 1, sizeof(ston_ht_h), file)) < sizeof(ston_ht_h)
+ || (bytes_written += fwrite(file, 1, ston_ht32_bytes(ht), file)) < (sizeof(ston_ht_h) + ston_ht32_bytes(ht))
+ || fseek(file, fpos_start, SEEK_SET) == 0)
+ return 0;
+ return bytes_written;
}
#endif
/* Returns a pointer to the row of data in the hashtable containing the provided
key, inserts if not found. Returns NULL on overflow.
*/
-STON_FUNC_STATIC
+STON_FUNC
uint32_t* ston_ht32_row
( struct ston_ht_header_t* ht,
uint32_t key
)
-{ uint32_t* row,* row_start = ston_ht32_start(ht);
+{ uint32_t* row;
+ uint32_t* row_start = ston_ht32_start(ht);
+ uint32_t* row_end = ston_ht32_end(ht);
uint16_t ht_cols = ston_ht_cols(ht);
size_t row_number = ston_ht_keyrow(ht,key);
- size_t row_max = ston_ht_rows(ht);
uint8_t looped = 0;
- next_row:
row = row_start + (row_number * ht_cols);
+ next_row:
if (row[0] != 0)
goto populated;
write_position:
populated:
if (row[0] == key)
goto write_position;
- if (row_number < row_max)
- row_number++;
+ if (row + ht_cols < row_end)
+ row += ht_cols;
else if (looped)
return NULL;
else
{ looped++;
- row_number = 0;
+ row = row_start;
}
goto next_row;
}
uint32_t value
)
{ uint32_t* value_location, old_value;
- value_location = ston_ht32_col(ht,key,column);
+ value_location = ston_ht32_entry(ht,key,column);
old_value = *value_location;
*value_location = value;
return old_value;
}
+/* Inserts a row of units into a hashtable, starting with the specified column.
+ Returns the number of elements that were written. This function will not
+ overflow internal buffers, but will return a short count (lower than the
+ provided 'units') when truncation of source data occurs. */
+STON_FUNC
+size_t
+ston_ht32_insertx
+( struct ston_ht_header_t* ht,
+ uint32_t key,
+ uint32_t* data_src,
+ size_t start_column,
+ size_t units
+)
+{ uint32_t* data_row = ston_ht32_row(ht,key);
+ uint32_t* data_limit = data_row + ston_ht_cols(ht);
+ uint32_t* data_trg = data_row + start_column;
+ if (data_row == NULL)
+ return 0;
+ while (units-- && data_trg < data_limit)
+ *data_trg++ = *data_src++;
+ return (size_t)(data_trg - data_row);
+}
+
+
/* STON Dynamic Hashtable Structure
A dynamic form of the generic hashtable implementation above which uses
external allocation.
*/
typedef struct ston_dht_header_t
-{ uint16_t ht_columns;
- uint8_t ht_2pow, ht_flags;
- void (*ht_alloc)(size_t);
- void* ht_pages[];
+{ uint16_t val_bytes;
+ uint8_t key_bytes;
+ uint8_t flags;
+}ston_dht_h;
+
+typedef struct ston_dht_t
+{ ston_dht_h header;
+ void* (*ht_alloc)(size_t);
+ void (*ht_free)(void*);
+ void (*ht_iter)(void*,void*,void*);
+ void* ht_user_data;
+ void* bucket_root;
+ size_t rowsize, bucketsize;
}* ston_dht;
+/* STON DHT API
+ Primary functions for creating hashtables, retrieving pointers to values,
+ iterating over all keys and values, and destroying hashtables. */
+STON_FUNC
+ston_dht ston_dht_new(uint16_t,uint8_t,void*(*)(size_t),void(*)(void*));
+STON_FUNC
+void* ston_dht_val(ston_dht,void*);
+STON_FUNC
+ston_dht ston_dht_free(ston_dht);
+STON_FUNC
+void ston_dht_iterate(ston_dht,void(*)(void*,void*,void*),void*);
+/* Recursive functions intended to be called by other functions, above */
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+void ston_dht_free_bucket(ston_dht,void*);
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+void ston_dht_iterate_r(ston_dht,void*);
+// Compatibility macros - Deprecated
+#define ston_dht32_new(_COL,_ALOC,_FRE) (ston_dht_new(4 * _COL, 4, _ALOC, _FRE))
+#define ston_dht32_row(_HT,_K) ((uint32_t*)((uint8_t*)ston_dht_val(_HT,&(_K)) - 4))
+#define ston_dht32_insertx(_HT,_K,_VP,_OFFS,_N) \
+ memcpy((uint32_t*)((uint8_t*)ston_dht_val(_HT,&(_K)) + ((_OFFS - 1) * 4)),_VP,_N * 4)
+
+/* New dynamic hashtable, provided value bytes, key bytes, allocator function,
+ and free function. Value bytes and key bytes are respectively constrained to
+ uint16 and uint8 so they can be aligned to hashtables encoded for
+ streaming */
+STON_FUNC
+ston_dht ston_dht_new
+( uint16_t val_bytes,
+ uint8_t key_bytes,
+ void* (*ht_alloc)(size_t),
+ void (*ht_free)(void*)
+)
+{ ston_dht ht = (ston_dht) ht_alloc(sizeof(struct ston_dht_t));
+ if (ht != NULL)
+ { ht->header.val_bytes = val_bytes;
+ ht->header.key_bytes = key_bytes;
+ ht->rowsize = sizeof(void*) + key_bytes + val_bytes;
+ ht->bucketsize = ht->rowsize * 0x100;
+ ht->ht_alloc = ht_alloc;
+ ht->ht_free = ht_free;
+ ht->bucket_root = ht_alloc(ht->bucketsize);
+ if (ht->bucket_root == NULL && ht_free != NULL)
+ ht_free(ht);
+ else
+ memset((ht->bucket_root), 0, ht->bucketsize);
+ }
+ return ht;
+}
+
-#define ston_dht_size(_HT) (ston_ht_size(_HT))
-#define ston_dht_rows(_HT) (ston_ht_rows(_HT))
-#define ston_dht_cols(_HT) (ston_ht_cols(_HT))
-#define ston_dht_keyrow(_HT,_KEY) (ston_ht_keyrow(_HT,_KEY))
-#define ston_dht_start(_HT) (_HT->ht_pages[0])
-#define ston_dht32_start(_HT) ((_uint32*)ston_dht_start(_HT))
-ston_dht ston_dht32_create(uint16_t,size_t,void*(*)(size_t));
-uint32_t* ston_dht32_row(ston_dht,uint32_t);
-#define ston_dht32_col(_HT,_KEY,_COL) (ston_dht32_row(_HT,_KEY) + _COL)
-uint32_t ston_dht32_insert(ston_dht,uint32_t,uint16_t,uint32_t);
-#define ston_dht32_insertx(_HT,_KEY,_COL,_VAL) *ston_dht32_col(_HT,_KEY,_COL) = _VAL
+/* Returns a pointer to the value in the hashtable matching the provided key,
+ inserting if not found, or NULL if a memory error occurs */
+STON_FUNC
+void* ston_dht_val
+( struct ston_dht_t* ht,
+ void* key
+)
+{ size_t key_bytes = ht->header.key_bytes;
+ uint8_t* key_byte = (uint8_t*)key;
+ uint8_t* bucket = (uint8_t*)ht->bucket_root;
+ uint8_t** bucketp;
+ uint8_t* row,* a,* b;
+ uint8_t a_not_empty;
+ size_t i;
+ next_row:
+ row = bucket + (ht->rowsize * (*key_byte));
+ a = row + sizeof(void*);
+ b = (uint8_t*)key;
+ a_not_empty = 0;
+ for (i = 0; i < key_bytes; i++)
+ { a_not_empty |= a[i];
+ if (a_not_empty && a[i] != b[i])
+ goto next_bucket;
+ }
+ if (!a_not_empty)
+ memcpy(row + sizeof(void*),key,key_bytes);
+ goto done;
+ next_bucket:
+ key_byte++;
+ bucketp = (uint8_t**)row;
+ if (*bucketp == NULL)
+ { if ((*bucketp = ht->ht_alloc(ht->bucketsize)) == NULL)
+ return NULL;
+ else
+ memset(*bucketp,0,ht->bucketsize);
+ }
+ bucket = *bucketp;
+ goto next_row;
+ done:
+ return (void*) row + sizeof(void*) + key_bytes;
+}
+/* Recursively frees all memory stored in the hashtable, and the hashtable
+ itself */
+STON_FUNC
+struct ston_dht_t* ston_dht_free
+( struct ston_dht_t* ht )
+{ void (*ht_free)(void*) = ht->ht_free;
+ if (ht_free == NULL)
+ return NULL;
+ ston_dht_free_bucket(ht, ht->bucket_root);
+ ht_free(ht);
+ return ht;
+}
+
+/* Recursive free function for nested buckets */
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+void ston_dht_free_bucket
+( struct ston_dht_t* ht,
+ void* bucket
+)
+{ void** bucket_cur = (void**)((uint8_t*)bucket);
+ void** bucket_max = (void**)((uint8_t*)bucket_cur + (ht->rowsize * 0x100));
+ while (bucket_cur < bucket_max)
+ { if (*bucket_cur != NULL)
+ ston_dht_free_bucket(ht, *bucket_cur);
+ bucket_cur = (void**)((uint8_t*)bucket_cur + ht->rowsize);
+ }
+ ht->ht_free(bucket);
+}
+
+/* Iterate over each key/value pair and execut 'fn' with key, value and
+ user_data as its arguments. user_data may be anything, even NULL, and is
+ expected to be referenced inside the body of 'fn' as the third argument of
+ 'fn' */
+STON_FUNC
+void ston_dht_iterate
+( struct ston_dht_t* ht,
+ void (*fn)(void*,void*,void*),
+ void* user_data
+)
+{ ht->ht_iter = fn;
+ ht->ht_user_data = user_data;
+ ston_dht_iterate_r(ht,ht->bucket_root);
+}
+
+/* Recursively iterate through the given bucket belonging to hashtable ht */
+STON_FUNC_STATIC
+STON_FUNC_NOINLINE
+void ston_dht_iterate_r
+( struct ston_dht_t* ht,
+ void* bucket
+)
+{ uint8_t* row = (uint8_t*)bucket;
+ uint8_t* row_max = (row + (ht->rowsize * 0x100));
+ while (row < row_max)
+ { if (*(void**)row != NULL)
+ ston_dht_iterate_r(ht, *(void**)row);
+ row += sizeof(void*);
+ ht->ht_iter((void*)row, (void*)(row + ht->header.key_bytes),ht->ht_user_data);
+ row += ht->header.key_bytes + ht->header.val_bytes;
+ }
+}
#endif //_STON_HT_H_