yap-6.3/C/blobs.c

//
//  blobs.c
//  yap
//
//  Created by VITOR SANTOS COSTA on 09/05/15.
//  Copyright (c) 2015 VITOR SANTOS COSTA. All rights reserved.
//

#include <stdio.h>
#include <string.h>

#include  "Yap.h"
#include  "Yatom.h"
#include "iopreds.h"
#include  "yapio.h"

/* for freeBSD9.1 */
#define _WITH_DPRINTF

#ifdef __APPLE__
#include "fmemopen.h"
#endif

#include "blobs.h"

static blob_type_t unregistered_blob_atom =
{ YAP_BLOB_MAGIC_B,
  PL_BLOB_NOCOPY|PL_BLOB_TEXT,
    "unregistered"
};

char * Yap_blob_to_string(AtomEntry *ref, const char *s0, size_t sz)
{
    int rc;
    char *s = (char *)s0;
    
    blob_type_t *type = RepBlobProp(ref->PropsOfAE)->blob_type;
    if (type->write) {
        FILE *f = fmemopen( s, sz, "w");
        if (f == NULL){
        // could not find stream;
        return NULL;
    }
    Atom at = AbsAtom(ref);
    rc = type->write(f, at, 0);
        fclose(f);    // return the final result.
    return s;
    } else {
        size_t sz0 = strlcpy( s, (char *)RepAtom( AtomSWIStream )->StrOfAE, sz);
        s = s+sz0;
        sz -= sz0;
#if defined(__linux__) || defined(__APPLE__)
        snprintf(s+strlen(s), sz0, "(%p)", ref);
#else
        snprintf(s+strlen(s), sz0, "(0x%p)", ref);
#endif
        return s;
    }
    return NULL;
}

int Yap_write_blob(AtomEntry *ref, FILE *stream)
{
    blob_type_t *type = RepBlobProp(ref->PropsOfAE)->blob_type;
    
    if (type->write) {
        
        Atom at = AbsAtom(ref);
        return type->write(stream, at, 0);
    } else {
#if defined(__linux__) || defined(__APPLE__)
            return fprintf(stream, "\'%s\'(%p)", RepAtom(AtomSWIStream)->StrOfAE, ref);
#else
            return fprintf(stream, "\'%s\'(0x%p)", RepAtom(AtomSWIStream)->StrOfAE, ref);
#endif
        
        }
    return 0;
    }


bool
YAP_is_blob(Term t, blob_type_t **type)
{
    CACHE_REGS
    Term yt = Yap_GetFromSlot(t);
    Atom a;
    BlobPropEntry *b;
    
    if (IsVarTerm(yt))
        return FALSE;
    if (!IsAtomTerm(yt))
        return FALSE;
    a = AtomOfTerm(yt);
    if (!IsBlob(a))
        return FALSE;
    b = RepBlobProp(a->PropsOfAE);
    *type = b->blob_type;
    return TRUE;
}


/* void check_chain(void); */

/* void check_chain(void) { */
/*   AtomEntry *ae, *old; */
/*     ae = Blobs; */
/*     old = NULL; */
/*     while (ae) { */
/*       old = ae; */
/*       ae = RepAtom(ae->NextOfAE); */
/*     } */
/* } */

AtomEntry *
Yap_lookupBlob(void *blob, size_t len, void *type0, int *new)
{
    BlobPropEntry *b;
    AtomEntry *ae;
    blob_type_t *type = type0;
    if (new)
        *new = FALSE;
    
    LOCK(Blobs_Lock);
    if (type->flags & PL_BLOB_UNIQUE) {
        /* just keep a linked chain for now */
        ae = Blobs;
        while (ae) {
            if (ae->PropsOfAE &&
                RepBlobProp(ae->PropsOfAE)->blob_type == type &&
                ae->rep.blob->length == len &&
                !memcmp(ae->rep.blob->data, blob, len)) {
                UNLOCK(Blobs_Lock);
                return ae;
            }
            ae = RepAtom(ae->NextOfAE);
        }
    }
    if (new)
        *new = TRUE;
    b = (BlobPropEntry *)Yap_AllocCodeSpace(sizeof(BlobPropEntry));
    if (!b) {
        UNLOCK(Blobs_Lock);
        return NULL;
    }
    b->NextOfPE = NIL;
    b->KindOfPE = BlobProperty;
    b->blob_type = type;
    ae = (AtomEntry *)Yap_AllocCodeSpace(sizeof(AtomEntry)+len+sizeof(size_t));
    if (!ae) {
        UNLOCK(Blobs_Lock);
        return NULL;
    }
    NOfBlobs++;
    INIT_RWLOCK(ae->ARWLock);
    ae->PropsOfAE = AbsBlobProp(b);
    ae->NextOfAE = AbsAtom(Blobs);
    ae->rep.blob->length = len;
    memcpy(ae->rep.blob->data, blob, len);
    Blobs = ae;
    if (NOfBlobs > NOfBlobsMax) {
        Yap_signal(YAP_CDOVF_SIGNAL);
    }
    UNLOCK(Blobs_Lock);
    return ae;
}

bool
YAP_unify_blob(Term *t, void *blob, size_t len, blob_type_t *type)
{
    AtomEntry *ae;
    
    if (!blob)
        return FALSE;
    ae = Yap_lookupBlob(blob, len, type, NULL);
    if (!ae) {
        return FALSE;
    }
    if (type->acquire) {
        type->acquire(AbsAtom(ae));
    }
    *t = MkAtomTerm(AbsAtom(ae));
    return true;
}

bool
YAP_get_blob(Term t, void **blob, size_t *len, blob_type_t **type)
{
    CACHE_REGS
    Atom a;
    Term tt;
    AtomEntry *ae;
    
    tt = Yap_GetFromSlot(t);
    if (IsVarTerm(tt))
        return FALSE;
    if (!IsAtomTerm(tt))
        return FALSE;
    a = AtomOfTerm(tt);
    if (!IsBlob(a))
        return FALSE;
    ae = RepAtom(a);
    if (type)
        *type = RepBlobProp(ae->PropsOfAE)->blob_type;
    if (len)
        *len = ae->rep.blob[0].length;
    if (blob)
        *blob = ae->rep.blob[0].data;
    return TRUE;
}

void *
YAP_blob_data(Atom x, size_t *len, blob_type_t **type)
{
    
    if (!IsBlob(x)) {
        if (IsWideAtom(x)) {
            if ( len )
                *len = wcslen(x->WStrOfAE);
            if ( type )
                *type = &unregistered_blob_atom;
            return x->WStrOfAE;
        }
        if ( len )
            *len = strlen((char *)x->StrOfAE);
        if ( type )
            *type = &unregistered_blob_atom;
        return x->StrOfAE;
    }
    if ( len )
        *len = x->rep.blob[0].length;
    if ( type )
        *type = RepBlobProp(x->PropsOfAE)->blob_type;
    return x->rep.blob[0].data;
}

void
YAP_register_blob_type(blob_type_t *type)
{
  type->next = (void *)BlobTypes;
  BlobTypes = (void*)type;
}

blob_type_t*
YAP_find_blob_type(const char* name)
{
  AtomEntry *a = RepAtom(Yap_LookupAtom(name));
    if (!IsBlob(a)) {
        return &unregistered_blob_atom;
    }
    return RepBlobProp(a->PropsOfAE)->blob_type;
}

bool
YAP_unregister_blob_type(blob_type_t *type)
{
    fprintf(stderr,"YAP_unregister_blob_type not implemented yet\n");
    return FALSE;
}

void
Yap_install_blobs(void)
{
    
}

/**
 * @}
 */