view audioDB_API.h @ 408:f0a69693eaef api-inversion

The lesser of two evils, part 1.

Most of the body of audiodb_insert_datum() will apply to
"LARGE_ADB"-type insertions: checking for the right flags, checking for
enough space free, synchronizing the header.  Wouldn't it be nice if we
could reuse all that code (or at least the bits that apply) without one
horrible almost-identical cut-and-paste job (see
batchinsert_large_adb(), or if that's not compelling enough, the four
almost-identical query loops from before the Great Refactoring).

Well, yes, it would.  Sadly C makes it mildly difficult, because its
functions are explicitly typed (so we can't pass arbitrary arguments of
other types, even if they're ABI-compatible), while its macros are
textual (which makes writing and maintaining them horrible).  The
thought of a union argument was briefly entertained and then discarded
as being just Too Weird.

So, instead, (ab)use the oldest trick in the book: void *.  Define an
adb_datum_internal_t which has void * instead of double *; the intention
is that this internal data type can be constructed both from an
adb_datum_t and some notional adb_reference_t (which looks very much
like an adb_insert_t at the time of writing, with char * structure
entries representing filenames).  This adb_datum_internal_t structure is
very much an internals-only thing, so put its definition in the
internals header.

Call what was previously audiodb_insert_datum() a new function
audiodb_insert_datum_internal(), made static so that really no-one is
tempted to call it other than ourselves.  audiodb_insert_datum() is then
trivial in terms of this new function, if stupidly tedious.  (If we were
playing dangerously, we could just perform a cast, but relying on the
fact that sizeof(double *) = sizeof(void *) would almost certainly end
up biting when we least expect.

Incidental inclusion in this patch, since I noticed it at the time:
actually check for the O2_FLAG_L2NORM before scribbling all over the
l2norm table.  Somewhat unsurprisingly, there are as yet no tests to
defend against this (harmless, as it turns out) erroneous behaviour.

#include <stdbool.h>
#include <stdint.h>

/* for API questions contact 
 * Christophe Rhodes [e-mail]
 * Ian Knopke [e-mail], [e-mail] */

/* Temporary workarounds */
typedef struct dbTableHeader adb_header_t;
int acquire_lock(int, bool);


/*******************************************************************/
/* Data types for API */

/* The main struct that stores the name of the database, and in future will hold all
 * kinds of other interesting information */
/* This basically gets passed around to all of the other functions */

/* FIXME: it might be that "adb_" isn't such a good prefix to use, and
   that we should prefer "audiodb_" */
typedef struct adb adb_t, *adb_ptr;

struct adb_datum {
  uint32_t nvectors;
  uint32_t dim;
  const char *key;
  double *data;
  double *power;
  double *times;
};
typedef struct adb_datum adb_datum_t;

//used for both insert and batchinsert
struct adbinsert {
  const char *features;
  const char *power;
  const char *key;
  const char *times;
};
typedef struct adbinsert adb_insert_t, *adb_insert_ptr;

/* struct for returning status results */
struct adbstatus {
    unsigned int numFiles;  
    unsigned int dim;
    unsigned int dudCount;
    unsigned int nullCount;
    unsigned int flags;
    uint64_t length;
    uint64_t data_region_size;
};
typedef struct adbstatus adb_status_t, *adb_status_ptr;

/* needed for constructing a query */
struct adbquery {

    char * querytype;
    char * feature; //usually a file of some kind
    char * power; //also a file
    char * keylist; //also a file
    char * qpoint;  //position 
    char * numpoints;
    char * radius; 
    char * resultlength; //how many results to make
    char * sequencelength; 
    char * sequencehop; 
    double absolute_threshold; 
    double relative_threshold;
    int exhaustive; //hidden option in gengetopt
    double expandfactor; //hidden
    int rotate; //hidden

};
typedef struct adbquery adb_query_t,*adb_query_ptr;

/* ... and for getting query results back */
struct adbqueryresult {

    int sizeRlist; /* do I really need to return all 4 sizes here */
    int sizeDist;
    int sizeQpos;
    int sizeSpos;
    char **Rlist;
    double *Dist;
    unsigned int *Qpos;
    unsigned int *Spos;

};
typedef struct adbqueryresult adb_queryresult_t, *adb_queryresult_ptr;


/*******************************************************************/
/* Function prototypes for API */


/* open an existing database */
/* returns a struct or NULL on failure */
adb_ptr audiodb_open(const char *path, int flags);

/* create a new database */
/* returns a struct or NULL on failure */
adb_ptr audiodb_create(const char *path, unsigned datasize, unsigned ntracks, unsigned datadim);

/* close a database */
void audiodb_close(adb_ptr db);

/* You'll need to turn both of these on to do anything useful */
int audiodb_l2norm(adb_ptr mydb);
int audiodb_power(adb_ptr mydb);

/* insert functions */
int audiodb_insert_datum(adb_t *, adb_datum_t *);
int audiodb_insert(adb_ptr mydb, adb_insert_ptr ins);
int audiodb_batchinsert(adb_ptr mydb, adb_insert_ptr ins, unsigned int size);

/* query function */
int audiodb_query(adb_ptr mydb, adb_query_ptr adbq, adb_queryresult_ptr adbqres);
  
/* database status */  
int audiodb_status(adb_ptr mydb, adb_status_ptr status);

/* varoius dump formats */
int audiodb_dump(adb_ptr mydb, const char *outputdir);