jni.c

这是一款基于PlaceLab软件开发的导航系统中间件的客户端程序.

#if defined(_WIN32_WCE)
#include <stdio.h>
#include <windows.h>
#include <tchar.h>
#endif

#include <jni.h>
#include <string.h>
#include "org_placelab_spotter_WiFiSpotter.h"
#include "spotter.h"


static int spotter_initialized=0;
static void saw_ap(char *bssid, char *ssid, int rss, int wep, int infrMode);
static void reset_cnt();
static jobjectArray gimme_java_aps(JNIEnv *env, jobject obj);


JNIEXPORT jboolean JNICALL
Java_org_placelab_spotter_WiFiSpotter_spotter_1init(JNIEnv *env,
								jobject cls)
{
	if (spotter_init() < 0) return 0;
	spotter_initialized = 1;
	return 1;
}


JNIEXPORT void JNICALL
Java_org_placelab_spotter_WiFiSpotter_spotter_1shutdown(JNIEnv *e,
								    jobject o)
{
	if (spotter_initialized) spotter_shutdown();
	spotter_initialized = 0;
}


JNIEXPORT jobjectArray JNICALL
Java_org_placelab_spotter_WiFiSpotter_spotter_1poll(JNIEnv *env,
								jobject obj)
{
	if (!spotter_initialized) return NULL;
	
	reset_cnt();
	if (spotter_poll(saw_ap) < 0) return NULL;
	return gimme_java_aps(env, obj);
}






/*********************************************************/

#define SIZEOF_SSID  33
#define SIZEOF_BSSID 18
#define MAX_APS 32
typedef char ssid_type [SIZEOF_SSID ];
typedef char bssid_type[SIZEOF_BSSID];

static char ssids [MAX_APS][SIZEOF_SSID ];
static char bssids[MAX_APS][SIZEOF_BSSID];
static int  rsss  [MAX_APS];
static int  aps   [MAX_APS];
static int  weps  [MAX_APS];
static int sawCnt=0;

static void
reset_cnt()
{
    sawCnt = 0;
}

static void
saw_ap(char *bssid, char *ssid, int rss, int wep, int infrMode)
{
    if (sawCnt > (MAX_APS-1)) {
	return;
    }
    strcpy(ssids[sawCnt],ssid);
    strcpy(bssids[sawCnt],bssid);
    rsss[sawCnt] = rss;
    aps[sawCnt]  = infrMode;
    weps[sawCnt] = wep;
    sawCnt++;
}


static jobjectArray
gimme_java_aps(JNIEnv *env, jobject obj)
{
    jstring str;
    char locStr[64];
    int i;
    //jclass cls = (*env)->GetObjectClass(env, obj);
    jobjectArray newArr = (*env)->NewObjectArray
	(env, sawCnt*5, (*env)->FindClass(env,"java/lang/String"),NULL);

    for (i=0;i<sawCnt;i++) {
	str= (*env)->NewStringUTF(env,bssids[i]);
	(*env)->SetObjectArrayElement(env,newArr,i*5,str);
	(*env)->DeleteLocalRef(env,str); // not really needed

	str= (*env)->NewStringUTF(env,ssids[i]);
	(*env)->SetObjectArrayElement(env,newArr,i*5+1,str);
	(*env)->DeleteLocalRef(env,str); // not really needed

	sprintf(locStr,"%d",rsss[i]);
	str= (*env)->NewStringUTF(env,locStr);
	(*env)->SetObjectArrayElement(env,newArr,i*5+2,str);
	(*env)->DeleteLocalRef(env,str); // not really needed

	sprintf(locStr,"%d",weps[i]);
	str= (*env)->NewStringUTF(env,locStr);
	(*env)->SetObjectArrayElement(env,newArr,i*5+3,str);
	(*env)->DeleteLocalRef(env,str); // not really needed

	sprintf(locStr,"%d",aps[i]);
	str= (*env)->NewStringUTF(env,locStr);
	(*env)->SetObjectArrayElement(env,newArr,i*5+4,str);
	(*env)->DeleteLocalRef(env,str); // not really needed

    }
    return newArr;
}