-#include "vp4.h"
+#include "database-builder.h"
+#include "db.h"
+#include "dprintf.h"
#include <algorithm>
#include <arpa/inet.h>
#include <assert.h>
#include <chrono>
-#include <endian.h>
-#include <fcntl.h>
+#include <getopt.h>
+#include <iosfwd>
+#include <locale.h>
#include <math.h>
#include <memory>
+#include <random>
+#include <stdint.h>
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
#include <string>
-#include <sys/mman.h>
#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include <unordered_map>
+#include <utility>
#include <vector>
-#include <zstd.h>
-
-#include "db.h"
-
-#define P4NENC_BOUND(n) ((n + 127) / 128 + (n + 32) * sizeof(uint32_t))
-#define dprintf(...)
-//#define dprintf(...) fprintf(stderr, __VA_ARGS__);
using namespace std;
using namespace std::chrono;
-string zstd_compress(const string &src, string *tempbuf);
-
-static inline uint32_t read_unigram(const string_view s, size_t idx)
-{
- if (idx < s.size()) {
- return (unsigned char)s[idx];
- } else {
- return 0;
- }
-}
-
-static inline uint32_t read_trigram(const string_view s, size_t start)
-{
- return read_unigram(s, start) |
- (read_unigram(s, start + 1) << 8) |
- (read_unigram(s, start + 2) << 16);
-}
+bool use_debug = false;
enum {
DBE_NORMAL = 0, /* A non-directory file */
uint8_t pad[4];
};
-class PostingListBuilder {
-public:
- void add_docid(uint32_t docid);
- void finish();
-
- string encoded;
- size_t num_docids = 0;
-
-private:
- void write_header(uint32_t docid);
- void append_block();
-
- vector<uint32_t> pending_docids;
-
- uint32_t last_block_end;
-};
-
-void PostingListBuilder::add_docid(uint32_t docid)
+string read_cstr(FILE *fp)
{
- // Deduplicate against the last inserted value, if any.
- if (pending_docids.empty()) {
- if (encoded.empty()) {
- // Very first docid.
- write_header(docid);
- ++num_docids;
- last_block_end = docid;
- return;
- } else if (docid == last_block_end) {
- return;
+ string ret;
+ for (;;) {
+ int ch = getc(fp);
+ if (ch == -1) {
+ perror("getc");
+ exit(1);
}
- } else {
- if (docid == pending_docids.back()) {
- return;
+ if (ch == 0) {
+ return ret;
}
+ ret.push_back(ch);
}
-
- pending_docids.push_back(docid);
- if (pending_docids.size() == 128) {
- append_block();
- pending_docids.clear();
- last_block_end = docid;
- }
- ++num_docids;
-}
-
-void PostingListBuilder::finish()
-{
- if (pending_docids.empty()) {
- return;
- }
-
- assert(!encoded.empty()); // write_header() should already have run.
-
- // No interleaving for partial blocks.
- unsigned char buf[P4NENC_BOUND(128)];
- unsigned char *end = p4d1enc32(pending_docids.data(), pending_docids.size(), buf, last_block_end);
- encoded.append(reinterpret_cast<char *>(buf), reinterpret_cast<char *>(end));
}
-void PostingListBuilder::append_block()
+void handle_directory(FILE *fp, DatabaseReceiver *receiver)
{
- unsigned char buf[P4NENC_BOUND(128)];
- assert(pending_docids.size() == 128);
- unsigned char *end = p4d1enc128v32(pending_docids.data(), 128, buf, last_block_end);
- encoded.append(reinterpret_cast<char *>(buf), reinterpret_cast<char *>(end));
-}
-
-void PostingListBuilder::write_header(uint32_t docid)
-{
- unsigned char buf[P4NENC_BOUND(1)];
- size_t bytes = p4nd1enc128v32(&docid, 1, buf);
- encoded.append(reinterpret_cast<char *>(buf), bytes);
-}
-
-class Corpus {
-public:
- Corpus(size_t block_size)
- : block_size(block_size) {}
- void add_file(string filename);
- void flush_block();
-
- vector<string> filename_blocks;
- unordered_map<uint32_t, PostingListBuilder> invindex;
- size_t num_files = 0, num_files_in_block = 0, num_blocks = 0;
-
-private:
- string current_block;
- string tempbuf;
- const size_t block_size;
-};
-
-void Corpus::add_file(string filename)
-{
- ++num_files;
- if (!current_block.empty()) {
- current_block.push_back('\0');
- }
- current_block += filename;
- if (++num_files_in_block == block_size) {
- flush_block();
- }
-}
-
-void Corpus::flush_block()
-{
- if (current_block.empty()) {
- return;
- }
-
- uint32_t docid = num_blocks;
-
- // Create trigrams.
- const char *ptr = current_block.c_str();
- while (ptr < current_block.c_str() + current_block.size()) {
- string_view s(ptr);
- if (s.size() >= 3) {
- for (size_t j = 0; j < s.size() - 2; ++j) {
- uint32_t trgm = read_trigram(s, j);
- invindex[trgm].add_docid(docid);
- }
+ db_directory dummy;
+ if (fread(&dummy, sizeof(dummy), 1, fp) != 1) {
+ if (feof(fp)) {
+ return;
+ } else {
+ perror("fread");
}
- ptr += s.size() + 1;
}
- // Compress and add the filename block.
- filename_blocks.push_back(zstd_compress(current_block, &tempbuf));
-
- current_block.clear();
- num_files_in_block = 0;
- ++num_blocks;
-}
-
-const char *handle_directory(const char *ptr, Corpus *corpus)
-{
- ptr += sizeof(db_directory);
-
- string dir_path = ptr;
- ptr += dir_path.size() + 1;
+ string dir_path = read_cstr(fp);
if (dir_path == "/") {
dir_path = "";
}
for (;;) {
- uint8_t type = *ptr++;
+ int type = getc(fp);
if (type == DBE_NORMAL) {
- string filename = ptr;
- corpus->add_file(dir_path + "/" + filename);
- ptr += filename.size() + 1;
+ string filename = read_cstr(fp);
+ receiver->add_file(dir_path + "/" + filename, unknown_dir_time);
} else if (type == DBE_DIRECTORY) {
- string dirname = ptr;
- corpus->add_file(dir_path + "/" + dirname);
- ptr += dirname.size() + 1;
+ string dirname = read_cstr(fp);
+ receiver->add_file(dir_path + "/" + dirname, unknown_dir_time);
} else {
- return ptr;
+ return; // Probably end.
}
}
}
-void read_mlocate(const char *filename, Corpus *corpus)
+void read_plaintext(FILE *fp, DatabaseReceiver *receiver)
{
- int fd = open(filename, O_RDONLY);
- if (fd == -1) {
- perror(filename);
+ if (fseek(fp, 0, SEEK_SET) != 0) {
+ perror("fseek");
exit(1);
}
- off_t len = lseek(fd, 0, SEEK_END);
- if (len == -1) {
- perror("lseek");
- exit(1);
+
+ while (!feof(fp)) {
+ char buf[1024];
+ if (fgets(buf, sizeof(buf), fp) == nullptr) {
+ break;
+ }
+ string s(buf);
+ assert(!s.empty());
+ while (s.back() != '\n' && !feof(fp)) {
+ // The string was longer than the buffer, so read again.
+ if (fgets(buf, sizeof(buf), fp) == nullptr) {
+ break;
+ }
+ s += buf;
+ }
+ if (!s.empty() && s.back() == '\n')
+ s.pop_back();
+ receiver->add_file(move(s), unknown_dir_time);
}
- const char *data = (char *)mmap(nullptr, len, PROT_READ, MAP_SHARED, fd, /*offset=*/0);
- if (data == MAP_FAILED) {
- perror("mmap");
+}
+
+void read_mlocate(FILE *fp, DatabaseReceiver *receiver)
+{
+ if (fseek(fp, 0, SEEK_SET) != 0) {
+ perror("fseek");
exit(1);
}
- const db_header *hdr = (const db_header *)data;
+ db_header hdr;
+ if (fread(&hdr, sizeof(hdr), 1, fp) != 1) {
+ perror("short read");
+ exit(1);
+ }
// TODO: Care about the base path.
- string path = data + sizeof(db_header);
- uint64_t offset = sizeof(db_header) + path.size() + 1 + ntohl(hdr->conf_size);
+ string path = read_cstr(fp);
- const char *ptr = data + offset;
- while (ptr < data + len) {
- ptr = handle_directory(ptr, corpus);
+ if (fseek(fp, ntohl(hdr.conf_size), SEEK_CUR) != 0) {
+ perror("skip conf block");
+ exit(1);
}
- munmap((void *)data, len);
- close(fd);
+ while (!feof(fp)) {
+ handle_directory(fp, receiver);
+ }
}
-string zstd_compress(const string &src, string *tempbuf)
+void do_build(const char *infile, const char *outfile, int block_size, bool plaintext, bool check_visibility)
{
- size_t max_size = ZSTD_compressBound(src.size());
- if (tempbuf->size() < max_size) {
- tempbuf->resize(max_size);
+ FILE *infp = fopen(infile, "rb");
+ if (infp == nullptr) {
+ perror(infile);
+ exit(1);
}
- size_t size = ZSTD_compress(&(*tempbuf)[0], max_size, src.data(), src.size(), /*level=*/6);
- return string(tempbuf->data(), size);
-}
-bool is_prime(uint32_t x)
-{
- if ((x % 2) == 0 || (x % 3) == 0) {
- return false;
+ // Train the dictionary by sampling real blocks.
+ // The documentation for ZDICT_trainFromBuffer() claims that a reasonable
+ // dictionary size is ~100 kB, but 1 kB seems to actually compress better for us,
+ // and decompress just as fast.
+ DictionaryBuilder builder(/*blocks_to_keep=*/1000, block_size);
+ if (plaintext) {
+ read_plaintext(infp, &builder);
+ } else {
+ read_mlocate(infp, &builder);
}
- uint32_t limit = ceil(sqrt(x));
- for (uint32_t factor = 5; factor <= limit; ++factor) {
- if ((x % factor) == 0) {
- return false;
- }
+ string dictionary = builder.train(1024);
+
+ DatabaseBuilder db(outfile, /*owner=*/-1, block_size, dictionary, check_visibility);
+ DatabaseReceiver *corpus = db.start_corpus(/*store_dir_times=*/false);
+ if (plaintext) {
+ read_plaintext(infp, corpus);
+ } else {
+ read_mlocate(infp, corpus);
}
- return true;
+ fclose(infp);
+
+ dprintf("Read %zu files from %s\n", corpus->num_files_seen(), infile);
+ db.finish_corpus();
}
-uint32_t next_prime(uint32_t x)
+void usage()
{
- if ((x % 2) == 0) {
- ++x;
- }
- while (!is_prime(x)) {
- x += 2;
- }
- return x;
+ printf(
+ "Usage: plocate-build MLOCATE_DB PLOCATE_DB\n"
+ "\n"
+ "Generate plocate index from mlocate.db, typically /var/lib/mlocate/mlocate.db.\n"
+ "Normally, the destination should be /var/lib/mlocate/plocate.db.\n"
+ "\n"
+ " -b, --block-size SIZE number of filenames to store in each block (default 32)\n"
+ " -p, --plaintext input is a plaintext file, not an mlocate database\n"
+ " -l, --require-visibility FLAG check visibility before reporting files\n"
+ " --help print this help\n"
+ " --version print version information\n");
}
-unique_ptr<Trigram[]> create_hashtable(const Corpus &corpus, const vector<uint32_t> &all_trigrams, uint32_t ht_size, uint32_t num_overflow_slots)
+void version()
{
- unique_ptr<Trigram[]> ht(new Trigram[ht_size + num_overflow_slots + 1]); // 1 for the sentinel element at the end.
- for (unsigned i = 0; i < ht_size + num_overflow_slots + 1; ++i) {
- ht[i].trgm = uint32_t(-1);
- ht[i].num_docids = 0;
- ht[i].offset = 0;
- }
- for (uint32_t trgm : all_trigrams) {
- // We don't know offset yet, so set it to zero.
- Trigram to_insert{trgm, uint32_t(corpus.invindex.find(trgm)->second.num_docids), 0};
-
- uint32_t bucket = hash_trigram(trgm, ht_size);
- unsigned distance = 0;
- while (ht[bucket].num_docids != 0) {
- // Robin Hood hashing; reduces the longest distance by a lot.
- unsigned other_distance = bucket - hash_trigram(ht[bucket].trgm, ht_size);
- if (distance > other_distance) {
- swap(to_insert, ht[bucket]);
- distance = other_distance;
- }
-
- ++bucket, ++distance;
- if (distance > num_overflow_slots) {
- return nullptr;
- }
- }
- ht[bucket] = to_insert;
- }
- return ht;
+ printf("plocate-build %s\n", PACKAGE_VERSION);
+ printf("Copyright 2020 Steinar H. Gunderson\n");
+ printf("License GPLv2+: GNU GPL version 2 or later <https://gnu.org/licenses/gpl.html>.\n");
+ printf("This is free software: you are free to change and redistribute it.\n");
+ printf("There is NO WARRANTY, to the extent permitted by law.\n");
}
-void do_build(const char *infile, const char *outfile, int block_size)
+bool parse_bool(const string &str, bool *result)
{
- steady_clock::time_point start __attribute__((unused)) = steady_clock::now();
-
- Corpus corpus(block_size);
-
- read_mlocate(infile, &corpus);
- if (false) { // To read a plain text file.
- FILE *fp = fopen(infile, "r");
- while (!feof(fp)) {
- char buf[1024];
- if (fgets(buf, 1024, fp) == nullptr || feof(fp)) {
- break;
- }
- string s(buf);
- if (s.back() == '\n')
- s.pop_back();
- corpus.add_file(move(s));
- }
- fclose(fp);
+ if (str == "0" || str == "no") {
+ *result = false;
+ return true;
}
- corpus.flush_block();
- dprintf("Read %zu files from %s\n", corpus.num_files, infile);
-
- size_t trigrams = 0, longest_posting_list = 0;
- size_t bytes_used = 0;
- for (auto &[trigram, pl_builder] : corpus.invindex) {
- pl_builder.finish();
- longest_posting_list = max(longest_posting_list, pl_builder.num_docids);
- trigrams += pl_builder.num_docids;
- bytes_used += pl_builder.encoded.size();
+ if (str == "1" || str == "yes") {
+ *result = true;
+ return true;
}
- dprintf("%zu files, %zu different trigrams, %zu entries, avg len %.2f, longest %zu\n",
- corpus.num_files, corpus.invindex.size(), trigrams, double(trigrams) / corpus.invindex.size(), longest_posting_list);
- dprintf("%zu bytes used for posting lists (%.2f bits/entry)\n", bytes_used, 8 * bytes_used / double(trigrams));
-
- dprintf("Building posting lists took %.1f ms.\n\n", 1e3 * duration<float>(steady_clock::now() - start).count());
-
- // Sort the trigrams, mostly to get a consistent result every time
- // (the hash table will put things in random order anyway).
- vector<uint32_t> all_trigrams;
- for (auto &[trigram, pl_builder] : corpus.invindex) {
- all_trigrams.push_back(trigram);
- }
- sort(all_trigrams.begin(), all_trigrams.end());
+ return false;
+}
- unique_ptr<Trigram[]> hashtable;
- uint32_t ht_size = next_prime(all_trigrams.size());
- constexpr unsigned num_overflow_slots = 16;
- for ( ;; ) {
- hashtable = create_hashtable(corpus, all_trigrams, ht_size, num_overflow_slots);
- if (hashtable == nullptr) {
- dprintf("Failed creating hash table of size %u, increasing by 5%% and trying again.\n", ht_size);
- ht_size = next_prime(ht_size * 1.05);
- } else {
- dprintf("Created hash table of size %u.\n\n", ht_size);
+int main(int argc, char **argv)
+{
+ static const struct option long_options[] = {
+ { "block-size", required_argument, 0, 'b' },
+ { "plaintext", no_argument, 0, 'p' },
+ { "require-visibility", required_argument, 0, 'l' },
+ { "help", no_argument, 0, 'h' },
+ { "version", no_argument, 0, 'V' },
+ { "debug", no_argument, 0, 'D' }, // Not documented.
+ { 0, 0, 0, 0 }
+ };
+
+ int block_size = 32;
+ bool plaintext = false;
+ bool check_visibility = true;
+
+ setlocale(LC_ALL, "");
+ for (;;) {
+ int option_index = 0;
+ int c = getopt_long(argc, argv, "b:hpl:VD", long_options, &option_index);
+ if (c == -1) {
break;
}
- }
-
- umask(0027);
- FILE *outfp = fopen(outfile, "wb");
-
- // Find the offsets for each posting list.
- size_t bytes_for_hashtable = (ht_size + num_overflow_slots + 1) * sizeof(Trigram);
- uint64_t offset = sizeof(Header) + bytes_for_hashtable;
- for (unsigned i = 0; i < ht_size + num_overflow_slots + 1; ++i) {
- hashtable[i].offset = offset; // Needs to be there even for empty slots.
- if (hashtable[i].num_docids == 0) {
- continue;
- }
-
- const PostingListBuilder &pl_builder = corpus.invindex[hashtable[i].trgm];
- offset += pl_builder.encoded.size();
- }
-
- // Write the header.
- Header hdr;
- memcpy(hdr.magic, "\0plocate", 8);
- hdr.version = 0;
- hdr.hashtable_size = ht_size;
- hdr.extra_ht_slots = num_overflow_slots;
- hdr.hash_table_offset_bytes = sizeof(hdr); // This member is just there for flexibility.
- hdr.filename_index_offset_bytes = offset;
- fwrite(&hdr, sizeof(hdr), 1, outfp);
-
- // Write the hash table.
- fwrite(hashtable.get(), ht_size + num_overflow_slots + 1, sizeof(Trigram), outfp);
-
- // Write the actual posting lists.
- size_t bytes_for_posting_lists = 0;
- for (unsigned i = 0; i < ht_size + num_overflow_slots + 1; ++i) {
- if (hashtable[i].num_docids == 0) {
- continue;
+ switch (c) {
+ case 'b':
+ block_size = atoi(optarg);
+ break;
+ case 'p':
+ plaintext = true;
+ break;
+ case 'l':
+ if (!parse_bool(optarg, &check_visibility) != 0) {
+ fprintf(stderr, "plocate-build: invalid value `%s' for --%s\n",
+ optarg, "require-visibility");
+ exit(EXIT_FAILURE);
+ }
+ break;
+ case 'h':
+ usage();
+ exit(0);
+ case 'V':
+ version();
+ exit(0);
+ case 'D':
+ use_debug = true;
+ break;
+ default:
+ exit(1);
}
- const string &encoded = corpus.invindex[hashtable[i].trgm].encoded;
- fwrite(encoded.data(), encoded.size(), 1, outfp);
- bytes_for_posting_lists += encoded.size();
- }
-
- // Stick an empty block at the end as sentinel.
- corpus.filename_blocks.push_back("");
-
- // Write the offsets to the filenames.
- size_t bytes_for_filename_index = 0, bytes_for_filenames = 0;
- offset = hdr.filename_index_offset_bytes + corpus.filename_blocks.size() * sizeof(offset);
- for (const string &filename : corpus.filename_blocks) {
- fwrite(&offset, sizeof(offset), 1, outfp);
- offset += filename.size();
- bytes_for_filename_index += sizeof(offset);
- bytes_for_filenames += filename.size();
}
- // Write the actual filenames.
- for (const string &filename : corpus.filename_blocks) {
- fwrite(filename.data(), filename.size(), 1, outfp);
+ if (argc - optind != 2) {
+ usage();
+ exit(1);
}
- fclose(outfp);
-
- size_t total_bytes __attribute__((unused)) = (bytes_for_hashtable + bytes_for_posting_lists + bytes_for_filename_index + bytes_for_filenames);
-
- dprintf("Block size: %7d files\n", block_size);
- dprintf("Hash table: %'7.1f MB\n", bytes_for_hashtable / 1048576.0);
- dprintf("Posting lists: %'7.1f MB\n", bytes_for_posting_lists / 1048576.0);
- dprintf("Filename index: %'7.1f MB\n", bytes_for_filename_index / 1048576.0);
- dprintf("Filenames: %'7.1f MB\n", bytes_for_filenames / 1048576.0);
- dprintf("Total: %'7.1f MB\n", total_bytes / 1048576.0);
- dprintf("\n");
-}
-
-int main(int argc, char **argv)
-{
- do_build(argv[1], argv[2], 32);
+ do_build(argv[optind], argv[optind + 1], block_size, plaintext, check_visibility);
exit(EXIT_SUCCESS);
}
projects / plocate / blobdiff