/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define C_LUCY_POSTINGPOOL
#define C_LUCY_RAWPOSTING
#define C_LUCY_MEMORYPOOL
#define C_LUCY_TERMINFO
#define C_LUCY_SKIPSTEPPER
#include "Lucy/Util/ToolSet.h"
#include "Lucy/Index/PostingPool.h"
#include "Lucy/Analysis/Inversion.h"
#include "Lucy/Plan/Architecture.h"
#include "Lucy/Plan/FieldType.h"
#include "Lucy/Index/LexiconReader.h"
#include "Lucy/Index/LexiconWriter.h"
#include "Lucy/Index/PolyReader.h"
#include "Lucy/Index/Posting.h"
#include "Lucy/Index/Posting/RawPosting.h"
#include "Lucy/Index/PostingListReader.h"
#include "Lucy/Index/RawLexicon.h"
#include "Lucy/Index/RawPostingList.h"
#include "Lucy/Index/Segment.h"
#include "Lucy/Index/SegReader.h"
#include "Lucy/Index/Similarity.h"
#include "Lucy/Index/Snapshot.h"
#include "Lucy/Index/SkipStepper.h"
#include "Lucy/Index/TermInfo.h"
#include "Lucy/Index/TermStepper.h"
#include "Lucy/Plan/Schema.h"
#include "Lucy/Store/Folder.h"
#include "Lucy/Store/InStream.h"
#include "Lucy/Store/OutStream.h"
#include "Lucy/Util/MemoryPool.h"
// Prepare to read back postings from disk.
static void
S_fresh_flip(PostingPool *self, InStream *lex_temp_in,
InStream *post_temp_in);
// Main loop.
static void
S_write_terms_and_postings(PostingPool *self, PostingWriter *post_writer,
OutStream *skip_stream);
PostingPool*
PostPool_new(Schema *schema, Snapshot *snapshot, Segment *segment,
PolyReader *polyreader, const CharBuf *field,
LexiconWriter *lex_writer, MemoryPool *mem_pool,
OutStream *lex_temp_out, OutStream *post_temp_out,
OutStream *skip_out) {
PostingPool *self = (PostingPool*)VTable_Make_Obj(POSTINGPOOL);
return PostPool_init(self, schema, snapshot, segment, polyreader, field,
lex_writer, mem_pool, lex_temp_out, post_temp_out,
skip_out);
}
PostingPool*
PostPool_init(PostingPool *self, Schema *schema, Snapshot *snapshot,
Segment *segment, PolyReader *polyreader, const CharBuf *field,
LexiconWriter *lex_writer, MemoryPool *mem_pool,
OutStream *lex_temp_out, OutStream *post_temp_out,
OutStream *skip_out) {
// Init.
SortEx_init((SortExternal*)self, sizeof(Obj*));
self->doc_base = 0;
self->last_doc_id = 0;
self->doc_map = NULL;
self->post_count = 0;
self->lexicon = NULL;
self->plist = NULL;
self->lex_temp_in = NULL;
self->post_temp_in = NULL;
self->lex_start = I64_MAX;
self->post_start = I64_MAX;
self->lex_end = 0;
self->post_end = 0;
self->skip_stepper = SkipStepper_new();
// Assign.
self->schema = (Schema*)INCREF(schema);
self->snapshot = (Snapshot*)INCREF(snapshot);
self->segment = (Segment*)INCREF(segment);
self->polyreader = (PolyReader*)INCREF(polyreader);
self->lex_writer = (LexiconWriter*)INCREF(lex_writer);
self->mem_pool = (MemoryPool*)INCREF(mem_pool);
self->field = CB_Clone(field);
self->lex_temp_out = (OutStream*)INCREF(lex_temp_out);
self->post_temp_out = (OutStream*)INCREF(post_temp_out);
self->skip_out = (OutStream*)INCREF(skip_out);
// Derive.
Similarity *sim = Schema_Fetch_Sim(schema, field);
self->posting = Sim_Make_Posting(sim);
self->type = (FieldType*)INCREF(Schema_Fetch_Type(schema, field));
self->field_num = Seg_Field_Num(segment, field);
return self;
}
void
PostPool_destroy(PostingPool *self) {
DECREF(self->schema);
DECREF(self->snapshot);
DECREF(self->segment);
DECREF(self->polyreader);
DECREF(self->lex_writer);
DECREF(self->mem_pool);
DECREF(self->field);
DECREF(self->doc_map);
DECREF(self->lexicon);
DECREF(self->plist);
DECREF(self->lex_temp_out);
DECREF(self->post_temp_out);
DECREF(self->skip_out);
DECREF(self->lex_temp_in);
DECREF(self->post_temp_in);
DECREF(self->posting);
DECREF(self->skip_stepper);
DECREF(self->type);
SUPER_DESTROY(self, POSTINGPOOL);
}
int
PostPool_compare(PostingPool *self, void *va, void *vb) {
RawPosting *const a = *(RawPosting**)va;
RawPosting *const b = *(RawPosting**)vb;
const size_t a_len = a->content_len;
const size_t b_len = b->content_len;
const size_t len = a_len < b_len ? a_len : b_len;
int comparison = memcmp(a->blob, b->blob, len);
UNUSED_VAR(self);
if (comparison == 0) {
// If a is a substring of b, it's less than b, so return a neg num.
comparison = a_len - b_len;
// Break ties by doc id.
if (comparison == 0) {
comparison = a->doc_id - b->doc_id;
}
}
return comparison;
}
MemoryPool*
PostPool_get_mem_pool(PostingPool *self) {
return self->mem_pool;
}
void
PostPool_flip(PostingPool *self) {
uint32_t num_runs = VA_Get_Size(self->runs);
uint32_t sub_thresh = num_runs > 0
? self->mem_thresh / num_runs
: self->mem_thresh;
if (num_runs) {
Folder *folder = PolyReader_Get_Folder(self->polyreader);
CharBuf *seg_name = Seg_Get_Name(self->segment);
CharBuf *lex_temp_path = CB_newf("%o/lextemp", seg_name);
CharBuf *post_temp_path = CB_newf("%o/ptemp", seg_name);
self->lex_temp_in = Folder_Open_In(folder, lex_temp_path);
if (!self->lex_temp_in) {
RETHROW(INCREF(Err_get_error()));
}
self->post_temp_in = Folder_Open_In(folder, post_temp_path);
if (!self->post_temp_in) {
RETHROW(INCREF(Err_get_error()));
}
DECREF(lex_temp_path);
DECREF(post_temp_path);
}
PostPool_Sort_Cache(self);
if (num_runs && (self->cache_max - self->cache_tick) > 0) {
uint32_t num_items = PostPool_Cache_Count(self);
// Cheap imitation of flush. FIXME.
PostingPool *run
= PostPool_new(self->schema, self->snapshot, self->segment,
self->polyreader, self->field, self->lex_writer,
self->mem_pool, self->lex_temp_out,
self->post_temp_out, self->skip_out);
PostPool_Grow_Cache(run, num_items);
memcpy(run->cache, ((Obj**)self->cache) + self->cache_tick,
num_items * sizeof(Obj*));
run->cache_max = num_items;
PostPool_Add_Run(self, (SortExternal*)run);
self->cache_tick = 0;
self->cache_max = 0;
}
// Assign.
for (uint32_t i = 0; i < num_runs; i++) {
PostingPool *run = (PostingPool*)VA_Fetch(self->runs, i);
if (run != NULL) {
PostPool_Set_Mem_Thresh(run, sub_thresh);
if (!run->lexicon) {
S_fresh_flip(run, self->lex_temp_in, self->post_temp_in);
}
}
}
self->flipped = true;
}
void
PostPool_add_segment(PostingPool *self, SegReader *reader, I32Array *doc_map,
int32_t doc_base) {
LexiconReader *lex_reader = (LexiconReader*)SegReader_Fetch(
reader, VTable_Get_Name(LEXICONREADER));
Lexicon *lexicon = lex_reader
? LexReader_Lexicon(lex_reader, self->field, NULL)
: NULL;
if (lexicon) {
PostingListReader *plist_reader
= (PostingListReader*)SegReader_Fetch(
reader, VTable_Get_Name(POSTINGLISTREADER));
PostingList *plist = plist_reader
? PListReader_Posting_List(plist_reader, self->field, NULL)
: NULL;
if (!plist) {
THROW(ERR, "Got a Lexicon but no PostingList for '%o' in '%o'",
self->field, SegReader_Get_Seg_Name(reader));
}
PostingPool *run
= PostPool_new(self->schema, self->snapshot, self->segment,
self->polyreader, self->field, self->lex_writer,
self->mem_pool, self->lex_temp_out,
self->post_temp_out, self->skip_out);
run->lexicon = lexicon;
run->plist = plist;
run->doc_base = doc_base;
run->doc_map = (I32Array*)INCREF(doc_map);
PostPool_Add_Run(self, (SortExternal*)run);
}
}
void
PostPool_shrink(PostingPool *self) {
if (self->cache_max - self->cache_tick > 0) {
size_t cache_count = PostPool_Cache_Count(self);
size_t size = cache_count * sizeof(Obj*);
if (self->cache_tick > 0) {
Obj **start = ((Obj**)self->cache) + self->cache_tick;
memmove(self->cache, start, size);
}
self->cache = (uint8_t*)REALLOCATE(self->cache, size);
self->cache_tick = 0;
self->cache_max = cache_count;
self->cache_cap = cache_count;
}
else {
FREEMEM(self->cache);
self->cache = NULL;
self->cache_tick = 0;
self->cache_max = 0;
self->cache_cap = 0;
}
self->scratch_cap = 0;
FREEMEM(self->scratch);
self->scratch = NULL;
// It's not necessary to iterate over the runs, because they don't have
// any cache costs until Refill() gets called.
}
void
PostPool_flush(PostingPool *self) {
// Don't add a run unless we have data to put in it.
if (PostPool_Cache_Count(self) == 0) { return; }
PostingPool *run
= PostPool_new(self->schema, self->snapshot, self->segment,
self->polyreader, self->field, self->lex_writer,
self->mem_pool, self->lex_temp_out,
self->post_temp_out, self->skip_out);
PostingWriter *post_writer
= (PostingWriter*)RawPostWriter_new(self->schema, self->snapshot,
self->segment, self->polyreader,
self->post_temp_out);
// Borrow the cache.
run->cache = self->cache;
run->cache_tick = self->cache_tick;
run->cache_max = self->cache_max;
run->cache_cap = self->cache_cap;
// Write to temp files.
LexWriter_Enter_Temp_Mode(self->lex_writer, self->field,
self->lex_temp_out);
run->lex_start = OutStream_Tell(self->lex_temp_out);
run->post_start = OutStream_Tell(self->post_temp_out);
PostPool_Sort_Cache(self);
S_write_terms_and_postings(run, post_writer, NULL);
run->lex_end = OutStream_Tell(self->lex_temp_out);
run->post_end = OutStream_Tell(self->post_temp_out);
LexWriter_Leave_Temp_Mode(self->lex_writer);
// Return the cache and empty it.
run->cache = NULL;
run->cache_tick = 0;
run->cache_max = 0;
run->cache_cap = 0;
PostPool_Clear_Cache(self);
// Add the run to the array.
PostPool_Add_Run(self, (SortExternal*)run);
DECREF(post_writer);
}
void
PostPool_finish(PostingPool *self) {
// Bail if there's no data.
if (!PostPool_Peek(self)) { return; }
Similarity *sim = Schema_Fetch_Sim(self->schema, self->field);
PostingWriter *post_writer
= Sim_Make_Posting_Writer(sim, self->schema, self->snapshot,
self->segment, self->polyreader,
self->field_num);
LexWriter_Start_Field(self->lex_writer, self->field_num);
S_write_terms_and_postings(self, post_writer, self->skip_out);
LexWriter_Finish_Field(self->lex_writer, self->field_num);
DECREF(post_writer);
}
static void
S_write_terms_and_postings(PostingPool *self, PostingWriter *post_writer,
OutStream *skip_stream) {
TermInfo *const tinfo = TInfo_new(0);
TermInfo *const skip_tinfo = TInfo_new(0);
CharBuf *const last_term_text = CB_new(0);
LexiconWriter *const lex_writer = self->lex_writer;
SkipStepper *const skip_stepper = self->skip_stepper;
int32_t last_doc_id = 0;
int32_t last_skip_doc = 0;
int64_t last_skip_filepos = 0;
const int32_t skip_interval
= Arch_Skip_Interval(Schema_Get_Architecture(self->schema));
// Prime heldover variables.
RawPosting *posting = (RawPosting*)CERTIFY(
(*(RawPosting**)PostPool_Fetch(self)),
RAWPOSTING);
CB_Mimic_Str(last_term_text, posting->blob, posting->content_len);
char *last_text_buf = (char*)CB_Get_Ptr8(last_term_text);
uint32_t last_text_size = CB_Get_Size(last_term_text);
SkipStepper_Set_ID_And_Filepos(skip_stepper, 0, 0);
while (1) {
bool_t same_text_as_last = true;
if (posting == NULL) {
// On the last iter, use an empty string to make LexiconWriter
// DTRT.
posting = &RAWPOSTING_BLANK;
same_text_as_last = false;
}
else {
// Compare once.
if (posting->content_len != last_text_size
|| memcmp(&posting->blob, last_text_buf, last_text_size) != 0
) {
same_text_as_last = false;
}
}
// If the term text changes, process the last term.
if (!same_text_as_last) {
// Hand off to LexiconWriter.
LexWriter_Add_Term(lex_writer, last_term_text, tinfo);
// Start each term afresh.
TInfo_Reset(tinfo);
PostWriter_Start_Term(post_writer, tinfo);
// Init skip data in preparation for the next term.
skip_stepper->doc_id = 0;
skip_stepper->filepos = tinfo->post_filepos;
last_skip_doc = 0;
last_skip_filepos = tinfo->post_filepos;
// Remember the term_text so we can write string diffs.
CB_Mimic_Str(last_term_text, posting->blob,
posting->content_len);
last_text_buf = (char*)CB_Get_Ptr8(last_term_text);
last_text_size = CB_Get_Size(last_term_text);
// Starting a new term, thus a new delta doc sequence at 0.
last_doc_id = 0;
}
// Bail on last iter before writing invalid posting data.
if (posting == &RAWPOSTING_BLANK) { break; }
// Write posting data.
PostWriter_Write_Posting(post_writer, posting);
// Doc freq lags by one iter.
tinfo->doc_freq++;
// Write skip data.
if (skip_stream != NULL
&& same_text_as_last
&& tinfo->doc_freq % skip_interval == 0
&& tinfo->doc_freq != 0
) {
// If first skip group, save skip stream pos for term info.
if (tinfo->doc_freq == skip_interval) {
tinfo->skip_filepos = OutStream_Tell(skip_stream);
}
// Write deltas.
last_skip_doc = skip_stepper->doc_id;
last_skip_filepos = skip_stepper->filepos;
skip_stepper->doc_id = posting->doc_id;
PostWriter_Update_Skip_Info(post_writer, skip_tinfo);
skip_stepper->filepos = skip_tinfo->post_filepos;
SkipStepper_Write_Record(skip_stepper, skip_stream,
last_skip_doc, last_skip_filepos);
}
// Remember last doc id because we need it for delta encoding.
last_doc_id = posting->doc_id;
// Retrieve the next posting from the sort pool.
// DECREF(posting); // No!! DON'T destroy!!!
void *address = PostPool_Fetch(self);
posting = address
? *(RawPosting**)address
: NULL;
}
// Clean up.
DECREF(last_term_text);
DECREF(skip_tinfo);
DECREF(tinfo);
}
uint32_t
PostPool_refill(PostingPool *self) {
Lexicon *const lexicon = self->lexicon;
PostingList *const plist = self->plist;
I32Array *const doc_map = self->doc_map;
const uint32_t mem_thresh = self->mem_thresh;
const int32_t doc_base = self->doc_base;
uint32_t num_elems = 0; // number of items recovered
MemoryPool *mem_pool;
CharBuf *term_text = NULL;
if (self->lexicon == NULL) { return 0; }
else { term_text = (CharBuf*)Lex_Get_Term(lexicon); }
// Make sure cache is empty.
if (self->cache_max - self->cache_tick > 0) {
THROW(ERR, "Refill called but cache contains %u32 items",
self->cache_max - self->cache_tick);
}
self->cache_max = 0;
self->cache_tick = 0;
// Ditch old MemoryPool and get another.
DECREF(self->mem_pool);
self->mem_pool = MemPool_new(0);
mem_pool = self->mem_pool;
while (1) {
RawPosting *raw_posting;
if (self->post_count == 0) {
// Read a term.
if (Lex_Next(lexicon)) {
self->post_count = Lex_Doc_Freq(lexicon);
term_text = (CharBuf*)Lex_Get_Term(lexicon);
if (term_text && !Obj_Is_A((Obj*)term_text, CHARBUF)) {
THROW(ERR, "Only CharBuf terms are supported for now");
}
Posting *posting = PList_Get_Posting(plist);
Post_Set_Doc_ID(posting, doc_base);
self->last_doc_id = doc_base;
}
// Bail if we've read everything in this run.
else {
break;
}
}
// Bail if we've hit the ceiling for this run's cache.
if (mem_pool->consumed >= mem_thresh && num_elems > 0) {
break;
}
// Read a posting from the input stream.
raw_posting = PList_Read_Raw(plist, self->last_doc_id, term_text,
mem_pool);
self->last_doc_id = raw_posting->doc_id;
self->post_count--;
// Skip deletions.
if (doc_map != NULL) {
const int32_t remapped
= I32Arr_Get(doc_map, raw_posting->doc_id - doc_base);
if (!remapped) {
continue;
}
raw_posting->doc_id = remapped;
}
// Add to the run's cache.
if (num_elems >= self->cache_cap) {
size_t new_cap = Memory_oversize(num_elems + 1, sizeof(Obj*));
PostPool_Grow_Cache(self, new_cap);
}
Obj **cache = (Obj**)self->cache;
cache[num_elems] = (Obj*)raw_posting;
num_elems++;
}
// Reset the cache array position and length; remember file pos.
self->cache_max = num_elems;
self->cache_tick = 0;
return num_elems;
}
void
PostPool_add_inversion(PostingPool *self, Inversion *inversion, int32_t doc_id,
float doc_boost, float length_norm) {
Post_Add_Inversion_To_Pool(self->posting, self, inversion, self->type,
doc_id, doc_boost, length_norm);
}
static void
S_fresh_flip(PostingPool *self, InStream *lex_temp_in,
InStream *post_temp_in) {
if (self->flipped) { THROW(ERR, "Can't Flip twice"); }
self->flipped = true;
// Sort RawPostings in cache, if any.
PostPool_Sort_Cache(self);
// Bail if never flushed.
if (self->lex_end == 0) { return; }
// Get a Lexicon.
CharBuf *lex_alias = CB_newf("%o-%i64-to-%i64",
InStream_Get_Filename(lex_temp_in),
self->lex_start, self->lex_end);
InStream *lex_temp_in_dupe = InStream_Reopen(
lex_temp_in, lex_alias, self->lex_start,
self->lex_end - self->lex_start);
self->lexicon = (Lexicon*)RawLex_new(
self->schema, self->field, lex_temp_in_dupe, 0,
self->lex_end - self->lex_start);
DECREF(lex_alias);
DECREF(lex_temp_in_dupe);
// Get a PostingList.
CharBuf *post_alias
= CB_newf("%o-%i64-to-%i64", InStream_Get_Filename(post_temp_in),
self->post_start, self->post_end);
InStream *post_temp_in_dupe
= InStream_Reopen(post_temp_in, post_alias, self->post_start,
self->post_end - self->post_start);
self->plist
= (PostingList*)RawPList_new(self->schema, self->field,
post_temp_in_dupe, 0,
self->post_end - self->post_start);
DECREF(post_alias);
DECREF(post_temp_in_dupe);
}