view power.cpp @ 580:633614461994

API for retrieving a track's data.

A new function, audiodb_retrieve_datum() fills a provided adb_datum_t
structure with the data corresponding to a given database key; the
companion audiodb_free_datum() function frees the data in a given datum
appropriately.

Just in case, I continue to require passing in the adb_t * as the first
argument to audiodb_free_datum(), even though it's not currently used:
I couldn't convince myself that _all_ possible implementations could
free a datum without reference to the adb_t.

This meant rewriting the internal code to use a new internal
audiodb_really_free_datum() function, which audiodb_free_datum() also
calls.

Sanity-checked by implementing a binding in sb-alien to this function,
lightly-tested.

All this fixes ticket:20 in Trac.

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

int audiodb_power(adb_t *adb) {
  if(!(adb->flags & O_RDWR)) {
    return 1;
  }
  if(adb->header->length > 0) {
    return 1;
  }

  adb->header->flags |= ADB_HEADER_FLAG_POWER;
  return audiodb_sync_header(adb);
}