view create.cpp @ 597:fac63f65753e

Remove LIBGSL from library link stage

At present, the library doesn't depend on libgsl.  If Windows porting
goes faster than APIs for sample and index, removing libgsl from the
link equation will help.

extern "C" {
#include "audioDB_API.h"
}
#include "audioDB-internals.h"

/* Make a new database.

(FIXME: this text, in particular the conditional, will not be true 
once we implement create flags rather than defaulting on format based
on the requested size arguments)

IF size(featuredata) < ADB_FIXME_LARGE_ADB_SIZE
   The database consists of:

   * a header (see adb_header_t definition);
   * keyTable: list of keys of tracks;
   * trackTable: Maps implicit feature index to a feature vector
     matrix (sizes of tracks)
   * featureTable: Lots of doubles;
   * timesTable: (start,end) time points for each feature vector;
   * powerTable: associated power for each feature vector;
   * l2normTable: squared l2norms for each feature vector.

ELSE the database consists of:

   * a header (see adb_header_t definition);
   * keyTable: list of keys of tracks
   * trackTable: sizes of tracks
   * featureTable: list of feature file names
   * timesTable: list of times file names
   * powerTable: list of power file names

*/

adb_t *audiodb_create(const char *path, unsigned datasize, unsigned ntracks, unsigned datadim) {
  int fd;
  adb_header_t *header = 0;
  off_t databytes, auxbytes;
  if(datasize == 0) {
    datasize = ADB_DEFAULT_DATASIZE;
  }
  if(ntracks == 0) {
    ntracks = ADB_DEFAULT_NTRACKS;
  }
  if(datadim == 0) {
    datadim = ADB_DEFAULT_DATADIM;
  }

  if ((fd = open(path, O_RDWR|O_CREAT|O_EXCL, ADB_CREAT_PERMISSIONS)) < 0) {
    goto error;
  }

  header = (adb_header_t *) malloc(sizeof(adb_header_t));
  if(!header) {
    goto error;
  }

  // Initialize header
  header->magic = ADB_MAGIC;
  header->version = ADB_FORMAT_VERSION;
  header->numFiles = 0;
  header->dim = 0;
  header->flags = 0;
  header->headerSize = ADB_HEADER_SIZE;
  header->length = 0;
  header->fileTableOffset = align_page_up(ADB_HEADER_SIZE);
  header->trackTableOffset = align_page_up(header->fileTableOffset + ADB_FILETABLE_ENTRY_SIZE*ntracks); //
  header->dataOffset = align_page_up(header->trackTableOffset + ADB_TRACKTABLE_ENTRY_SIZE*ntracks);

  databytes = ((off_t) datasize) * 1024 * 1024;
  auxbytes = databytes / datadim;

  // If database will fit in a single file the vectors are copied into the AudioDB instance
  // Else all the vectors are left on the FileSystem and we use the dataOffset as storage
  // for the location of the features, powers and times files (assuming that arbitrary keys are used for the fileTable)
  if(ntracks < ADB_FIXME_LARGE_ADB_NTRACKS && datasize < ADB_FIXME_LARGE_ADB_SIZE) {
    header->timesTableOffset = align_page_up(header->dataOffset + databytes);
    header->powerTableOffset = align_page_up(header->timesTableOffset + 2*auxbytes);
    header->l2normTableOffset = align_page_up(header->powerTableOffset + auxbytes);
    header->dbSize = align_page_up(header->l2normTableOffset + auxbytes);
  } else { // Create REFERENCES ADB, features and powers kept on filesystem
    header->flags |= ADB_HEADER_FLAG_REFERENCES;
    header->timesTableOffset = align_page_up(header->dataOffset + ADB_FILETABLE_ENTRY_SIZE*ntracks);
    header->powerTableOffset = align_page_up(header->timesTableOffset + ADB_FILETABLE_ENTRY_SIZE*ntracks);
    header->l2normTableOffset = align_page_up(header->powerTableOffset + ADB_FILETABLE_ENTRY_SIZE*ntracks);
    header->dbSize = header->l2normTableOffset;
  }

  write_or_goto_error(fd, header, ADB_HEADER_SIZE);

  // go to the location corresponding to the last byte of the database
  // file, and write a byte there.
  lseek_set_or_goto_error(fd, header->dbSize - 1);
  write_or_goto_error(fd, "", 1);

  free(header);
  return audiodb_open(path, O_RDWR);

 error:
  maybe_free(header);
  return NULL;
}