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yap-6.3/packages/myddas/myddas_wkb2prolog.c
2014-01-24 19:59:42 +00:00

383 lines
7.6 KiB
C

#if defined MYDDAS_MYSQL
#include <stdio.h>
#include <stdlib.h>
#include "Yap.h"
#include <netinet/in.h>
#include "myddas_wkb.h"
#include "myddas_wkb2prolog.h"
static void readswap4(uint32 *buf);
static void readswap8(double *buf);
static byte get_hostbyteorder(void);
static byte get_inbyteorder(void);
static uint32 get_wkbType(void);
static Term get_point(char *functor USES_REGS);
static Term get_linestring(char *functor);
static Term get_polygon(char *functor);
static Term get_geometry(uint32 type);
static int swaporder;
static byte inbyteorder, hostbyteorder;
static byte *cursor;
Term wkb2prolog(char *wkb) {
uint32 type;
cursor = wkb;
/*ignore the SRID 4 bytes*/
cursor += 4;
/*byteorder*/
hostbyteorder = get_hostbyteorder();
inbyteorder = get_inbyteorder();
swaporder = 0;
if ( hostbyteorder != inbyteorder )
swaporder = 1;
type = get_wkbType();
return get_geometry(type);
}
static byte get_hostbyteorder(void){
uint16_t host = 5;
uint16_t net;
net = htons(host);
if ( net == host )
return(WKBXDR);
else
return(WKBNDR);
}
static byte get_inbyteorder(void){
byte b = cursor[0];
if (b != WKBNDR && b != WKBXDR) {
fprintf(stderr, "Unknown byteorder: %d\n",b);
exit(0);
}
cursor++;
return(b);
}
static uint32 get_wkbType(void){
uint32 u;
/* read the type */
readswap4(&u);
if (u > WKBMAXTYPE || u < WKBMINTYPE) {
fprintf(stderr, "Unknown type: %d\n",u);
exit(0);
}
return(u);
}
static void readswap4(uint32 *buf){
((byte *) buf)[0] = cursor[0];
((byte *) buf)[1] = cursor[1];
((byte *) buf)[2] = cursor[2];
((byte *) buf)[3] = cursor[3];
if ( swaporder ) {
if ( inbyteorder == WKBXDR ) {
*buf = (uint32)ntohl((u_long)*buf);
} else {
byte u[4];
u[0] = ((byte *) buf)[3];
u[1] = ((byte *) buf)[2];
u[2] = ((byte *) buf)[1];
u[3] = ((byte *) buf)[0];
((byte *) buf)[0] = u[0];
((byte *) buf)[1] = u[1];
((byte *) buf)[2] = u[2];
((byte *) buf)[3] = u[3];
}
}
cursor += 4;
}
static void readswap8(double *buf) {
((byte *) buf)[0] = cursor[0];
((byte *) buf)[1] = cursor[1];
((byte *) buf)[2] = cursor[2];
((byte *) buf)[3] = cursor[3];
((byte *) buf)[4] = cursor[4];
((byte *) buf)[5] = cursor[5];
((byte *) buf)[6] = cursor[6];
((byte *) buf)[7] = cursor[7];
if ( swaporder ) {
if ( inbyteorder == WKBXDR ) {
u_long u[2];
u[0] = ((u_long *) buf)[0];
u[1] = ((u_long *) buf)[1];
((u_long *) buf)[1] = ntohl(u[0]);
((u_long *) buf)[0] = ntohl(u[1]);
} else {
byte u[8];
u[0] = ((byte *) buf)[7];
u[1] = ((byte *) buf)[6];
u[2] = ((byte *) buf)[5];
u[3] = ((byte *) buf)[4];
u[4] = ((byte *) buf)[3];
u[5] = ((byte *) buf)[2];
u[6] = ((byte *) buf)[1];
u[7] = ((byte *) buf)[0];
((byte *) buf)[0] = u[0];
((byte *) buf)[1] = u[1];
((byte *) buf)[2] = u[2];
((byte *) buf)[3] = u[3];
((byte *) buf)[4] = u[4];
((byte *) buf)[5] = u[5];
((byte *) buf)[6] = u[6];
((byte *) buf)[7] = u[7];
}
}
cursor += 8;
}
static Term get_point(char *func USES_REGS){
Term args[2];
Functor functor;
double d;
if(func == NULL)
/*functor "," => (_,_)*/
functor = Yap_MkFunctor(Yap_LookupAtom(","), 2);
else
functor = Yap_MkFunctor(Yap_LookupAtom(func), 2);
/* read the X */
readswap8(&d);
args[0] = MkFloatTerm(d);
/* read the Y */
readswap8(&d);
args[1] = MkFloatTerm(d);
return Yap_MkApplTerm(functor, 2, args);
}
static Term get_linestring(char *func){
CACHE_REGS
Term *c_list;
Term list;
Functor functor;
uint32 n;
int i;
/* read the number of vertices */
readswap4(&n);
/* space for arguments */
c_list = (Term *) calloc(sizeof(Term),n);
for ( i = 0; i < n; i++) {
c_list[i] = get_point(NULL PASS_REGS);
}
list = MkAtomTerm(Yap_LookupAtom("[]"));
for (i = n - 1; i >= 0; i--) {
list = MkPairTerm(c_list[i],list);
}
if(func == NULL)
return list;
else{
functor = Yap_MkFunctor(Yap_LookupAtom(func), 1);
return Yap_MkApplTerm(functor, 1, &list);
}
}
static Term get_polygon(char *func){
CACHE_REGS
uint32 r;
int i;
Functor functor;
Term *c_list;
Term list;
/* read the number of rings */
readswap4(&r);
/* space for rings */
c_list = (Term *) calloc(sizeof(Term),r);
for ( i = 0; i < r; i++ ) {
c_list[i] = get_linestring(NULL);
}
list = MkAtomTerm(Yap_LookupAtom("[]"));
for (i = r - 1; i >= 0; i--) {
list = MkPairTerm(c_list[i],list);
}
if(func == NULL)
return list;
else{
functor = Yap_MkFunctor(Yap_LookupAtom("polygon"), 1);
return Yap_MkApplTerm(functor, 1, &list);
}
}
static Term get_geometry(uint32 type){
CACHE_REGS
switch(type) {
case WKBPOINT:
return get_point("point" PASS_REGS);
case WKBLINESTRING:
return get_linestring("linestring");
case WKBPOLYGON:
return get_polygon("polygon");
case WKBMULTIPOINT:
{
uint32 n;
int i;
Functor functor;
Term *c_list;
Term list;
/* read the number of points */
readswap4(&n);
/* space for points */
c_list = (Term *) calloc(sizeof(Term),n);
for ( i = 0; i < n; i++ ) {
/* read (and ignore) the byteorder and type */
get_inbyteorder();
get_wkbType();
c_list[i] = get_point(NULL PASS_REGS);
}
list = MkAtomTerm(Yap_LookupAtom("[]"));
for (i = n - 1; i >= 0; i--) {
list = MkPairTerm(c_list[i],list);
}
functor = Yap_MkFunctor(Yap_LookupAtom("multipoint"), 1);
return Yap_MkApplTerm(functor, 1, &list);
}
case WKBMULTILINESTRING:
{
uint32 n;
int i;
Functor functor;
Term *c_list;
Term list;
/* read the number of polygons */
readswap4(&n);
/* space for polygons*/
c_list = (Term *) calloc(sizeof(Term),n);
for ( i = 0; i < n; i++ ) {
/* read (and ignore) the byteorder and type */
get_inbyteorder();
get_wkbType();
c_list[i] = get_linestring(NULL);
}
list = MkAtomTerm(Yap_LookupAtom("[]"));
for (i = n - 1; i >= 0; i--) {
list = MkPairTerm(c_list[i],list);
}
functor = Yap_MkFunctor(Yap_LookupAtom("multilinestring"), 1);
return Yap_MkApplTerm(functor, 1, &list);
}
case WKBMULTIPOLYGON:
{
uint32 n;
int i;
Functor functor;
Term *c_list;
Term list;
/* read the number of polygons */
readswap4(&n);
/* space for polygons*/
c_list = (Term *) calloc(sizeof(Term),n);
for ( i = 0; i < n; i++ ) {
/* read (and ignore) the byteorder and type */
get_inbyteorder();
get_wkbType();
c_list[i] = get_polygon(NULL);
}
list = MkAtomTerm(Yap_LookupAtom("[]"));
for (i = n - 1; i >= 0; i--) {
list = MkPairTerm(c_list[i],list);
}
functor = Yap_MkFunctor(Yap_LookupAtom("multipolygon"), 1);
return Yap_MkApplTerm(functor, 1, &list);
}
case WKBGEOMETRYCOLLECTION:
{
uint32 n;
int i;
Functor functor;
Term *c_list;
Term list;
/* read the number of geometries */
readswap4(&n);
/* space for geometries*/
c_list = (Term *) calloc(sizeof(Term),n);
for ( i = 0; i < n; i++ ) {
get_inbyteorder();
c_list[i] = get_geometry(get_wkbType());
}
list = MkAtomTerm(Yap_LookupAtom("[]"));
for (i = n - 1; i >= 0; i--) {
list = MkPairTerm(c_list[i],list);
}
functor = Yap_MkFunctor(Yap_LookupAtom("geometrycollection"), 1);
return Yap_MkApplTerm(functor, 1, &list);
}
}
return MkAtomTerm(Yap_LookupAtom("[]"));
}
#endif /*MYDDAS_MYSQL*/