view l2norm.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"

static int audiodb_l2norm_existing(adb_t *adb) {
  double *data_buffer = 0, *l2norm_buffer = 0;
  size_t data_buffer_size = align_page_up(adb->header->length);
  size_t nvectors = adb->header->length / (sizeof(double) * adb->header->dim);
  /* FIXME: this allocation of the vector data buffer will lose if we
   * ever turn the l2norm flag on when we have already inserted a
   * large number of vectors, as the malloc() will fail.  "Don't do
   * that, then" is one possible answer. */
  data_buffer = (double *) malloc(data_buffer_size);
  if (!data_buffer) {
    goto error;
  }
  lseek_set_or_goto_error(adb->fd, adb->header->dataOffset);
  read_or_goto_error(adb->fd, data_buffer, data_buffer_size);

  l2norm_buffer = (double *) malloc(nvectors * sizeof(double));
  if(!l2norm_buffer) {
    goto error;
  }
  audiodb_l2norm_buffer(data_buffer, adb->header->dim, nvectors, l2norm_buffer);
  lseek_set_or_goto_error(adb->fd, adb->header->l2normTableOffset);
  write_or_goto_error(adb->fd, l2norm_buffer, nvectors * sizeof(double));

  free(l2norm_buffer);
  free(data_buffer);

  return 0;

 error:
  if(data_buffer) {
    free(data_buffer);
  }
  if(l2norm_buffer) {
    free(l2norm_buffer);
  }
  return 1;
}

int audiodb_l2norm(adb_t *adb) {
  if(!(adb->flags & O_RDWR)) {
    return 1;
  }
  if(adb->header->flags & ADB_HEADER_FLAG_L2NORM) {
    /* non-error code for forthcoming backwards-compatibility
     * reasons */
    return 0;
  }
  if((!(adb->header->flags & ADB_HEADER_FLAG_REFERENCES)) && 
     (adb->header->length > 0)) {
    if(audiodb_l2norm_existing(adb)) {
      goto error;
    }
  }
  adb->header->flags |= ADB_HEADER_FLAG_L2NORM;
  return audiodb_sync_header(adb);

 error:
  return 1;
}