view open.cpp @ 524:469b50a3dd84 multiprobeLSH

Fixed a bug in LSH hashtable writing to disk that doesn't always sort the t2 entries into strict weak ordering. Now it does. Lots of debugging informational code inserted.
author mas01mc
date Wed, 28 Jan 2009 16:02:17 +0000
parents cc2b97d020b1
children cfa74bcc1249
line wrap: on
line source
extern "C" {
#include "audioDB_API.h"
}
#include "audioDB-internals.h"

static bool audiodb_check_header(adb_header_t *header) {
  /* FIXME: use syslog() or write to stderr or something to give the
     poor user some diagnostics. */
  if(header->magic == ADB_OLD_MAGIC) {
    return false;
  }
  if(header->magic != ADB_MAGIC) {
    return false;
  }
  if(header->version != ADB_FORMAT_VERSION) {
    return false;
  }
  if(header->headerSize != ADB_HEADER_SIZE) {
    return false;
  }
  return true;
}

static int audiodb_collect_keys(adb_t *adb) {
  char *key_table = 0;
  size_t key_table_length = 0;

  if(adb->header->length > 0) {
    unsigned nfiles = adb->header->numFiles;
    key_table_length = align_page_up(nfiles * ADB_FILETABLE_ENTRY_SIZE);
    mmap_or_goto_error(char *, key_table, adb->header->fileTableOffset, key_table_length);
    for (unsigned int k = 0; k < nfiles; k++) {
      adb->keys->push_back(key_table + k*ADB_FILETABLE_ENTRY_SIZE);
      (*adb->keymap)[(key_table + k*ADB_FILETABLE_ENTRY_SIZE)] = k;
    }
    munmap(key_table, key_table_length);
  }

  return 0;

 error:
  maybe_munmap(key_table, key_table_length);
  return 1;
}

static int audiodb_collect_track_lengths(adb_t *adb) {
  uint32_t *track_table = 0;
  size_t track_table_length = 0;
  if(adb->header->length > 0) {
    unsigned nfiles = adb->header->numFiles;
    track_table_length = align_page_up(nfiles * ADB_TRACKTABLE_ENTRY_SIZE);
    mmap_or_goto_error(uint32_t *, track_table, adb->header->trackTableOffset, track_table_length);
    off_t offset = 0;
    for (unsigned int k = 0; k < nfiles; k++) {
      uint32_t track_length = track_table[k];
      adb->track_lengths->push_back(track_length);
      adb->track_offsets->push_back(offset);
      offset += track_length * adb->header->dim * sizeof(double);
    }
    munmap(track_table, track_table_length);
  }

  return 0;

 error:
  maybe_munmap(track_table, track_table_length);
  return 1;
}

adb_t *audiodb_open(const char *path, int flags) {
  adb_t *adb = 0;
  int fd = -1;

  flags &= (O_RDONLY|O_RDWR);
  fd = open(path, flags);
  if(fd == -1) {
    goto error;
  }
  if(acquire_lock(fd, flags == O_RDWR)) {
    goto error;
  }

  adb = (adb_t *) calloc(1, sizeof(adb_t));
  if(!adb) {
    goto error;
  }
  adb->fd = fd;
  adb->flags = flags;
  adb->path = (char *) malloc(1+strlen(path));
  if(!(adb->path)) {
    goto error;
  }
  strcpy(adb->path, path);

  adb->header = (adb_header_t *) malloc(sizeof(adb_header_t));
  if(!(adb->header)) {
    goto error;
  }
  if(read(fd, (char *) adb->header, ADB_HEADER_SIZE) != ADB_HEADER_SIZE) {
    goto error;
  }
  if(!audiodb_check_header(adb->header)) {
    goto error;
  }

  adb->keys = new std::vector<std::string>;
  if(!adb->keys) {
    goto error;
  }
  adb->keymap = new std::map<std::string,uint32_t>;
  if(!adb->keymap) {
    goto error;
  }
  if(audiodb_collect_keys(adb)) {
    goto error;
  }
  adb->track_lengths = new std::vector<uint32_t>;
  if(!adb->track_lengths) {
    goto error;
  }
  adb->track_lengths->reserve(adb->header->numFiles);
  adb->track_offsets = new std::vector<off_t>;
  if(!adb->track_offsets) {
    goto error;
  }
  adb->track_offsets->reserve(adb->header->numFiles);
  if(audiodb_collect_track_lengths(adb)) {
    goto error;
  }
  adb->cached_lsh = 0;
  return adb;

 error:
  if(adb) {
    if(adb->header) {
      free(adb->header);
    }
    if(adb->path) {
      free(adb->path);
    }
    if(adb->keys) {
      delete adb->keys;
    }
    if(adb->keymap) {
      delete adb->keymap;
    }
    if(adb->track_lengths) {
      delete adb->track_lengths;
    }
    free(adb);
  }
  if(fd != -1) {
    close(fd);
  }
  return NULL;
}