+#include "database-builder.h"
+#include "db.h"
+#include "dprintf.h"
+
+#include <algorithm>
+#include <arpa/inet.h>
+#include <assert.h>
+#include <chrono>
+#include <getopt.h>
+#include <iosfwd>
+#include <math.h>
+#include <memory>
+#include <random>
+#include <stdint.h>
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
-#include <algorithm>
-#include <unordered_map>
#include <string>
-#include <vector>
-#include <chrono>
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/mman.h>
-#include <arpa/inet.h>
-#include <endian.h>
-#include <sys/types.h>
#include <sys/stat.h>
-
-#include "vp4.h"
-
-#define P4NENC_BOUND(n) ((n+127)/128+(n+32)*sizeof(uint32_t))
-#define dprintf(...)
-//#define dprintf(...) fprintf(stderr, __VA_ARGS__);
+#include <utility>
+#include <vector>
using namespace std;
using namespace std::chrono;
-
-static inline uint32_t read_unigram(const string &s, size_t idx)
-{
- if (idx < s.size()) {
- return (unsigned char)s[idx];
- } else {
- return 0;
- }
-}
-static inline uint32_t read_trigram(const string &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 */
- DBE_DIRECTORY = 1, /* A directory */
- DBE_END = 2 /* End of directory contents; contains no name */
+enum {
+ DBE_NORMAL = 0, /* A non-directory file */
+ DBE_DIRECTORY = 1, /* A directory */
+ DBE_END = 2 /* End of directory contents; contains no name */
};
// From mlocate.
-struct db_header
-{
+struct db_header {
uint8_t magic[8];
uint32_t conf_size;
uint8_t version;
};
// From mlocate.
-struct db_directory
-{
+struct db_directory {
uint64_t time_sec;
uint32_t time_nsec;
uint8_t pad[4];
};
-const char *handle_directory(const char *ptr, vector<string> *files)
+string read_cstr(FILE *fp)
{
- ptr += sizeof(db_directory);
+ string ret;
+ for (;;) {
+ int ch = getc(fp);
+ if (ch == -1) {
+ perror("getc");
+ exit(1);
+ }
+ if (ch == 0) {
+ return ret;
+ }
+ ret.push_back(ch);
+ }
+}
+
+void handle_directory(FILE *fp, DatabaseReceiver *receiver)
+{
+ db_directory dummy;
+ if (fread(&dummy, sizeof(dummy), 1, fp) != 1) {
+ if (feof(fp)) {
+ return;
+ } else {
+ perror("fread");
+ }
+ }
- 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++;
+
+ for (;;) {
+ int type = getc(fp);
if (type == DBE_NORMAL) {
- string filename = ptr;
- files->push_back(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;
- files->push_back(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, vector<string> *files)
+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, files);
+ 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);
+ }
}
-void do_build(const char *infile, const char *outfile)
+void do_build(const char *infile, const char *outfile, int block_size, bool plaintext)
{
- //steady_clock::time_point start = steady_clock::now();
-
- vector<string> files;
- read_mlocate(infile, &files);
- 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();
- files.push_back(move(s));
- }
- fclose(fp);
- }
- dprintf("Read %zu files from %s\n", files.size(), infile);
-
- unordered_map<uint32_t, string> pl;
- size_t trigrams = 0, longest_posting_list = 0;
- unordered_map<uint32_t, vector<uint32_t>> invindex;
- for (size_t i = 0; i < files.size(); ++i) {
- const string &s = files[i];
- if (s.size() >= 3) {
- for (size_t j = 0; j < s.size() - 2; ++j) {
- uint32_t trgm = read_trigram(s, j);
- invindex[trgm].push_back(i);
- }
- }
- }
- string buf;
- size_t bytes_used = 0;
- for (auto &[trigram, docids] : invindex) {
- auto last = unique(docids.begin(), docids.end());
- docids.erase(last, docids.end());
- longest_posting_list = max(longest_posting_list, docids.size());
- trigrams += docids.size();
-
- size_t bytes_needed = P4NENC_BOUND(docids.size());
- if (buf.size() < bytes_needed) buf.resize(bytes_needed);
- size_t bytes = p4nd1enc128v32(&docids[0], docids.size(), reinterpret_cast<unsigned char *>(&buf[0]));
- pl[trigram] = string(buf.data(), bytes);
- bytes_used += bytes;
- }
- dprintf("%zu files, %zu different trigrams, %zu entries, avg len %.2f, longest %zu\n",
- files.size(), invindex.size(), trigrams, double(trigrams) / invindex.size(), longest_posting_list);
-
- dprintf("%zu bytes used for posting lists (%.2f bits/entry)\n", bytes_used, 8 * bytes_used / double(trigrams));
- //steady_clock::time_point end = steady_clock::now();
- dprintf("Building posting lists took %.1f ms.\n\n", 1e3 * duration<float>(end - start).count());
-
- vector<uint32_t> all_trigrams;
- for (auto &[trigram, docids] : invindex) {
- all_trigrams.push_back(trigram);
+ FILE *infp = fopen(infile, "rb");
+ if (infp == nullptr) {
+ perror(infile);
+ exit(1);
}
- sort(all_trigrams.begin(), all_trigrams.end());
- umask(0027);
- FILE *outfp = fopen(outfile, "wb");
-
- // Write the header.
- uint64_t num_trigrams = invindex.size(); // 64 to get alignment.
- fwrite(&num_trigrams, sizeof(num_trigrams), 1, outfp);
-
- // Find out where the posting lists will end.
- uint64_t offset = sizeof(uint64_t) * 2 + 16 * all_trigrams.size();
- uint64_t filename_index_offset = offset;
- for (uint32_t trgm : all_trigrams) {
- filename_index_offset += pl[trgm].size();
- }
- fwrite(&filename_index_offset, sizeof(filename_index_offset), 1, outfp);
-
- size_t bytes_for_trigrams = 0, bytes_for_posting_lists = 0, bytes_for_filename_index = 0, bytes_for_filenames = 0;
-
- for (uint32_t trgm : all_trigrams) {
- // 16 bytes: trgm (4), number of docids (4), byte offset (8)
- fwrite(&trgm, sizeof(trgm), 1, outfp); // One byte wasted, but OK.
- uint32_t num_docids = invindex[trgm].size();
- fwrite(&num_docids, sizeof(num_docids), 1, outfp);
- fwrite(&offset, sizeof(offset), 1, outfp);
- offset += pl[trgm].size();
- bytes_for_trigrams += 16;
+ // 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);
}
+ string dictionary = builder.train(1024);
- // Write the actual posting lists.
- for (uint32_t trgm : all_trigrams) {
- fwrite(pl[trgm].data(), pl[trgm].size(), 1, outfp);
- bytes_for_posting_lists += pl[trgm].size();
+ DatabaseBuilder db(outfile, /*owner=*/-1, block_size, dictionary);
+ Corpus *corpus = db.start_corpus(/*store_dir_times=*/false);
+ if (plaintext) {
+ read_plaintext(infp, corpus);
+ } else {
+ read_mlocate(infp, corpus);
}
+ fclose(infp);
- // Write the offsets to the filenames.
- offset = filename_index_offset + files.size() * sizeof(offset);
- for (const string &filename : files) {
- fwrite(&offset, sizeof(offset), 1, outfp);
- offset += filename.size() + 1;
- bytes_for_filename_index += sizeof(offset);
- bytes_for_filenames += filename.size() + 1;
- }
-
- // Write the actual filenames.
- for (const string &filename : files) {
- fwrite(filename.c_str(), filename.size() + 1, 1, outfp);
- }
+ dprintf("Read %zu files from %s\n", corpus->num_files, infile);
+ db.finish_corpus();
+}
- fclose(outfp);
+void usage()
+{
+ 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"
+ " --help print this help\n"
+ " --version print version information\n");
+}
- dprintf("Trigrams: %'7.1f MB\n", bytes_for_trigrams / 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("\n");
+void version()
+{
+ 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");
}
int main(int argc, char **argv)
{
- do_build(argv[1], argv[2]);
+ static const struct option long_options[] = {
+ { "block-size", required_argument, 0, 'b' },
+ { "plaintext", no_argument, 0, 'p' },
+ { "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;
+
+ setlocale(LC_ALL, "");
+ for (;;) {
+ int option_index = 0;
+ int c = getopt_long(argc, argv, "b:hpVD", long_options, &option_index);
+ if (c == -1) {
+ break;
+ }
+ switch (c) {
+ case 'b':
+ block_size = atoi(optarg);
+ break;
+ case 'p':
+ plaintext = true;
+ break;
+ case 'h':
+ usage();
+ exit(0);
+ case 'V':
+ version();
+ exit(0);
+ case 'D':
+ use_debug = true;
+ break;
+ default:
+ exit(1);
+ }
+ }
+
+ if (argc - optind != 2) {
+ usage();
+ exit(1);
+ }
+
+ do_build(argv[optind], argv[optind + 1], block_size, plaintext);
exit(EXIT_SUCCESS);
}