C回调与JNA使JRE崩溃 [英] C callback with JNA makes JRE crash
问题描述
我在处理JNA中的回调时遇到问题。
我试图使用一个使用回调来处理多个会话事件out,连接问题...)。
会话对象(称为 sp_session
)是一个不透明结构。所有回调都注册在 sp_session_callbacks
结构中。根据API,我应该声明callbacks对象,并将其放入创建 sp_session
对象时将提供的Config对象中。如果我不想使用某些回调,我应该用 null
初始化它们。 API使用 __ stdcall
调用约定。
这是一个与我的问题相关的C头文件:
#define SP_CALLCONV __stdcall
typedef struct sp_session sp_session; ///<表示会话
typedef枚举sp_error {
SP_ERROR_OK = 0,
SP_ERROR_BAD_API_VERSION = 1,
/ *更多错误* /
} sp_error;
typedef struct sp_session_callbacks {
/ **
*当登录已处理并成功时调用
* /
void(SP_CALLCONV * logged_in) sp_session * session,sp_error error);
/ **
*处理注销后调用。如果你初始化一个注销操作,或者如果
*是一个永久的连接错误
*
* @param [in] session session
* /
void(SP_CALLCONV * logged_out)(sp_session * session);
/ **
*在出现连接错误时调用,库在重新连接到Spotify服务时出现问题
*。可以多次调用(作为
* long,因为存在问题)
* /
void(SP_CALLCONV * connection_error)(sp_session * session,sp_error error);
/ *更多回调* /
} sp_session_callbacks;
/ **
*初始化会话。返回的会话将被初始化,但您需要
*才能执行任何其他操作
* /
SP_LIBEXPORT(sp_error)sp_session_create(const sp_session_config * config,sp_session ** sess);
这是我的等效JNA代码:
sp_session对象
public class sp_session extends PointerType {
public sp_session(Pointer address){
super(address);
}
public sp_session(){
super();
}
}
sp_session_callbacks对象包含所有回调
public class sp_session_callbacks extends Structure {
public LoggedIn logged_in;
public LoggedOut logged_out;
public ConnectionError connection_error;
}
回调对象(这里是LoggedIn,每个回调一个)
public interface LoggedIn extends StdCallCallback {
public void logged_in(sp_session session, int error);
}
本地库,声明所有方法
public interface JLibspotify extends StdCallLibrary {
int sessionCreate(sp_session_config config,PointerByReference sess);
int sessionLogin(sp_session session,String username,String password);
//由API定义的所有其他方法
}
我的主类,绑定所有在一起
public class Test {
static {
System.loadLibrary(libspotify);
}
public static void main(String [] args){
JLibspotify lib =(JLibspotify)Native.loadLibrary(libspotify,JLibspotify.class);
sp_session_config cfg = new sp_session_config();
}
sp_session_callbacks sessCallbacks = new sp_session_callbacks();
LoggedIn loggedInCallback = new LoggedIn(){
public void logged_in(sp_session session,int error){
System.out.println(logged_in()called);
}
};
sessCallbacks.logged_in = loggedInCallback;
cfg.session_callbacks = sessCallbacks;
PointerByReference sessionPbr = new PointerByReference();
int error_id = sessionCreate(cfg,sessionPbr); // CRASHES HERE
sp_session mySession = new sp_session(sessionPbr.getValue());
}
}
因此,sessionCreate函数调用会使JRE崩溃 EXCEPTION_ACCESS_VIOLATION(0xc0000005)有问题的框架:C [jna3666290841889849729.dll + 0xa3f4]
看起来像logged_in回调是导致这个,因为当我设置为 null
它运行确定。此外,如果我初始化 connection_error
回调,它具有完全相同的签名,它也不会崩溃。
我运行的版本3.2.7的JNA。我试图与前版本(3.0.9),它也失败了。
我运行的JDK 1.7测试版本,但我尝试与1.6和它也失败。
谢谢!
#
#Java运行时环境检测到致命错误:
#
#EXCEPTION_ACCESS_VIOLATION(0xc0000005)at pc = 0x0499a3f4,pid = 1368,tid = 1344
#
#JRE版本:7.0-b129
#Java VM:Java HotSpot TM客户端VM(21.0-b01混合模式,共享windows-x86)
#有问题的框架:
#C [jna3666290841889849729.dll + 0xa3f4]
#
#如果您想提交错误报告,请访问:
#http://java.sun.com/webapps/bugreport/crash.jsp
#崩溃发生在Java虚拟机之外的本机代码中。
#见有问题的框架,在哪里报告错误。
#
--------------- THREAD ---------------
当前线程(0x01b79400):JavaThreadmain[_thread_in_native,id = 1344,stack(0x00340000,0x00390000)]
siginfo:ExceptionCode = 0xc0000005,读取地址0x1993053a
$ b b寄存器:
EAX = 0x19930522,EBX = 0x100dc77c,ECX = 0x00010004,EDX = 0x1008d3e0
ESP = 0x0038f58c,EBP = 0x0038f5b4,ESI = 0x0038f5a4,EDI = 0x100b79b0
EIP = 0x0499a3f4,EFLAGS = 0x00210212
堆栈顶部:(sp = 0x0038f58c)
0x0038f58c:100dc77c 0038f5a4 00010004 0038f688
0x0038f59c:05983de0 05981330 0598289c 05983de0
0x0038f5ac:05983de0 00000014 0038f688 1008d3ea
0x0038f5bc:05983de0 10030d77 0038fc44 100b79b0
0x0038f5cc:ffffffff 1008d334 00000000 05983de0
0x0038f5dc:1008d3e0 05983fc4 1008d9fd 0038f770
0x0038f5ec:00000000 00000000 7275016a 055310b0
0x0038f5fc:00000000 00010001 00000000 00000000
说明:(pc = 0x0499a3f4)
0x0499a3d4:01 00 89 e5 57 56 8d 75 f0 53 83 ec 1c 8b 7d 14
0x0499a3e4:8b 5f 4c 8b 03 89 4c 24 08 89 74 24 04 89 1c 24
0x0499a3f4:ff 50 18 83 ec 0c 85 c0 0f 94 c0 0f b6 c0 85 c0
0x0499a404:89 45 ec 75 19 8b 03 31 d2 89 54 24 08 89 74 24
注册到内存映射:
EAX = 0x19930522是未知值
EBX = 0x100dc77c是未知值
ECX = 0x00010004是未知值
EDX = 0x1008d3e0是未知值
ESP = 0x0038f58c指向线程堆栈:0x01b79400
EBP = 0x0038f5b4指向堆栈线程:0x01b79400
ESI = 0x0038f5a4指向线程的堆栈:0x01b79400
EDI = 0x100b79b0是未知值
堆栈:[0x00340000,0x00390000],sp = 0x0038f58c,自由空间= 317k
本机框架(J =编译的Java代码,j =解释,Vv = VM代码,C =本地代码)
C [jna3666290841889849729.dll + 0xa3f4] Java_com_sun_jna_Native_initialize_1ffi_1type + 0x1054
C [libspotify.dll + 0x8d3ea] sp_error_message + 0x35a
C [jna3666290841889849729.dll + 0xcb77] Java_com_sun_jna_Native_initialize_1ffi_1type + 0x37d7
C [jna3666290841889849729.dll + 0xc7c2] Java_com_sun_jna_Native_initialize_1ffi_1type + 0x3422
C [jna3666290841889849729。 dll + 0x4561] Java_com_sun_jna_Pointer__1getString + 0xa31
C [jna3666290841889849729.dll + 0x4d2e] Java_com_sun_jna_Function_invokeInt + 0x2e
j com.sun.jna.Function.invokeInt(I [Ljava / lang / Object;)I + 0
j com.sun.jna.Function.invoke([Ljava / lang / Object; Ljava / lang / Class; Z)Ljava / lang / Object; +315
j com.sun.jna.Function.invoke / lang / Class; [Ljava / lang / Object; Ljava / util / Map;)Ljava / lang / Object; +214
j com.sun.jna.Library $ Handler.invoke(Ljava / lang / Object; Ljava / lang / reflect / Method; [Ljava / lang / Object;)Ljava / lang / Object; +341
j $ Proxy0.sp_session_create(Lcom / nbarraille / jspotify / model / sp_session_config; Lcom / sun / jna / ptr / PointerByReference;)I + 20
j com.nbarraille.jspotify.main.Test.main([Ljava / lang / String;)V + 273
v〜StubRoutines :: call_stub
V [jvm。 dll + 0x115f6d]
V [jvm.dll + 0x1b788e]
V [jvm.dll + 0x115fed]
V [jvm.dll + 0xa2507]
V [jvm.dll + 0xac867]
C [javaw.exe + 0x209e]
C [javaw.exe + 0xa23b]
C [javaw.exe + 0xa2c5]
C [kernel32.dll + 0x51194] BaseThreadInitThunk + 0x12
C [ntdll.dll + 0x5b429] RtlInitializeExceptionChain + 0x63
C [ntdll.dll + 0x5b3fc] RtlInitializeExceptionChain + 0x36
Java框架: ,j = interpret,Vv = VM代码)
j com.sun.jna.Function.invokeInt(I [Ljava / lang / Object;)I + 0
j com.sun.jna.Function.invoke [Ljava / lang / Object; Ljava / lang / Class; Z] Ljava / lang / Object; +315
j com.sun.jna.Function.invoke(Ljava / lang / Ljava / lang / Object; Ljava / lang / Object; +214
j com.sun.jna.Library $ Handler.invoke(Ljava / lang / Object; Ljava / lang / reflect / Object;)Ljava / lang / Object; +341
j $ Proxy0.sp_session_create(Lcom / nbarraille / jspotify / model / sp_session_config; Lcom / sun / jna / ptr / PointerByReference;)I + 20
j com。 nbarraille.jspotify.main.Test.main([Ljava / lang / String;)V + 273
v〜StubRoutines :: call_stub
------------ --- PROCESS ---------------
Java Threads:(=>当前线程)
0x0182fc00 JavaThread低内存检测器守护程序[_thread_blocked,id = 4664,stack(0x04170000,0x041c0000)]
0x0182ac00 JavaThreadC1 CompilerThread0守护程序[_thread_blocked,id = 1728, ,0x01b70000)]
0x01829800 JavaThreadAttach Listener守护进程[_thread_blocked,id = 112,stack(0x04020000,0x04070000)]
0x01826400 JavaThreadSignal Dispatcher守护进程[_thread_blocked,id = 5836,stack ,0x03ef0000)]
0x01819800 JavaThreadFinalizer守护程序[_thread_blocked,id = 4724,stack(0x03f80000,0x03fd0000)]
0x01817800 JavaThreadReference Handler守护程序[_thread_blocked,id = 3940, 0x01b20000)]
=> 0x01b79400 JavaThreadmain[_thread_in_native,id = 1344,stack(0x00340000,0x00390000)]
其他主题:
0x01816400 VMThread [stack:0x01a30000 ,0x01a80000] [id = 3876]
0x01843000 WatcherThread [stack:0x040d0000,0x04120000] [id = 4636]
虚拟机状态:未处于正常执行状态
VM Mutex / Monitor当前由一个线程拥有:None
Heap
def新一代总计4928K,使用3630K [0x23450000,0x239a0000,0x289a0000)
eden空间4416K,82 %used [0x23450000,0x237db858,0x238a0000)
从空间512K,0%使用[0x238a0000,0x238a0000,0x23920000)
到空间512K,使用0%[0x23920000,0x23920000,0x239a0000]
生成总共10944K,使用0K [0x289a0000,0x29450000,0x33450000)
空间10944K,0%使用[0x289a0000,0x289a0000,0x289a0200,0x29450000)
压缩永久总共12288K,使用860K [0x33450000,0x34050000, 0x37450000)
空间12288K,7%已使用[0x33450000,0x33527190,0x33527200,0x34050000)
ro空间10240K,43%已使用[0x37450000,0x3789ce40,0x3789d000,0x37e50000]
rw空间12288K, 53%used [0x37e50000,0x384c2710,0x384c2800,0x38a50000)
代码缓存[0x01e90000,0x01f20000,0x03e90000)
total_blobs = 234 nmethods = 82 adapters = 88 free_code_cache = 32972224 largest_free_block = 0
动态库:
0x00880000 - 0x008b0000 C:\Program Files\Java\jdk1.7.0\bin\javaw.exe
0x778f0000 - 0x77a2d000 C:\Windows \SYSTEM32\\\
tdll.dll
0x77070000 - 0x77144000 C:\Windows\system32\kernel32.dll
0x75cf0000 - 0x75d3a000 C:\Windows \system32\KERNELBASE.dll
0x60000000 - 0x60041000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\ Midas_00078_002\midas32.dll
0x61000000 - 0x61028000 C:\Program Files\BitDefender\BitDefender 2011 \Active Virus Control\Midas_00078_002\plugin_base.m32
0x67000000 - 0x67048000 C:\Program Files\BitDefender\BitDefender 2011 \Active Virus Control\ Midas_00078_002\plugin_nt.m32
0x64000000 - 0x64021000 C:\Program Files\BitDefender\BitDefender 2011 \Active Virus Control\ Midas_00078_002\plugin_registry.m32
0x62000000 - 0x6202d000 C:\Program Files\BitDefender\BitDefender 2011 \Active Virus Control\Midas_00078_002\plugin_extra.m32
0x65000000 - 0x6501a000 C:\Program Files\BitDefender\BitDefender 2011 \Active Virus Control\ Midas_00078_002\plugin_net.m32
0x63000000 - 0x630a6000 C:\Program Files\BitDefender\BitDefender 2011 \Active Virus Control\ Midas_00078_002\plugin_fragments.m32
0x75e10000 - 0x75eb0000 C:\Windows \system32\ADVAPI32.dll
0x775c0000 - 0x7766c000 C:\Windows \system32 \msvcrt.dll
0x75d50000 - 0x75d69000 C:\Windows \SYSTEM32\sechost.dll
0x77670000 - 0x77711000 C:\ Windows \system32\RPCRT4.dll
0x76f00000 - 0x76fc9000 C:\Windows \system32\USER32.dll
0x77a50000 - 0x77a9e000 C:\Windows \system32\GDI32.dll
0x77a30000 - 0x77a3a000 C:\Windows\system32\LPK.dll
0x75d70000 - 0x75e0d000 C:\Windows \system32\USP10.dll
0x74830000 - 0x749ce000 C:\ Windows\WinSxS\x86_microsoft.windows.common-controls_6595b64144ccf1df_6.0.7600.16661_none_420fe3fa2b8113bd\COMCTL32.dll
0x772f0000 - 0x77347000 C:\Windows\system32\SHLWAPI.dll
0x775a0000 - 0x775bf000 C :\Windows \system32\IMM32.DLL
0x75eb0000 - 0x75f7c000 C:\Windows \system32\MSCTF.dll
0x72740000 - 0x727fe000 C:\Program Files\Java\ jdk1.7.0\jre\bin\msvcr100.dll
0x01b80000 - 0x01e89000 C:\Program Files\Java\jdk1.7.0\jre\bin\client\jvm.dll
0x746c0000 - 0x746f2000 C:\Windows \system32\WINMM.dll
0x73920000 - 0x7392c000 C:\Program Files \Java\jdk1.7.0\\\\\\\\\\ dll
0x73330000 - 0x73350000 C:\Program Files\Java\jdk1.7.0\jre\bin\java.dll
0x75d40000 - 0x75d45000 C:\Windows \system32 \ PSAPI.DLL
0x733a0000 - 0x733b3000 C:\Program Files\Java\jdk1.7.0\jre\bin\zip.dll
0x10000000 - 0x10259000 C:\Windows \System32 \libspotify.dll
0x77150000 - 0x77185000 C:\Windows\system32\WS2_32.dll
0x77a40000 - 0x77a46000 C:\Windows \system32\NSI.dll
0x75ba0000 - 0x75cbc000 C:\Windows\system32\CRYPT32.dll
0x75ab0000 - 0x75abc000 C:\Windows \system32\MSASN1.dll
0x74ee0000 - 0x74f38000 C:\Windows \system32 \WINHTTP.dll
0x74e90000 - 0x74edf000 C:\Windows\system32\webio.dll
0x754c0000 - 0x754d6000 C:\Windows \system32\CRYPTSP.dll
0x75260000 - 0x7529b000 C:\Windows \system32\rsaenh.dll
0x750a0000 - 0x750b7000 C:\Windows \system32\USERENV.dll
0x75a40000 - 0x75a4b000 C:\Windows \system32 \profapi.dll
0x75a30000 - 0x75a3c000 C:\Windows\system32\CRYPTBASE.dll
0x728a0000 - 0x728b6000 C:\Program Files\Java\jdk1.7.0\jre\\ \\bin \\\
et.dll
0x75480000 - 0x754bc000 C:\Windows\system32\mswsock.dll
0x75470000 - 0x75476000 C:\Windows \System32\wship6.dll
0x73950000 - 0x73960000 C:\Windows\system32\NLAapi.dll
0x75340000 - 0x75384000 C:\Windows \system32\DNSAPI.dll
0x71030000 - 0x71038000 C:\Windows \\ \\ System32 \winrnr.dll
0x71020000 - 0x71030000 C:\Windows \system32\\\
apinsp.dll
0x71000000 - 0x71012000 C:\Windows \system32\pnrpnsp.dll
0x74fd0000 - 0x74fd5000 C:\Windows\System32\wshtcpip.dll
0x74d30000 - 0x74d4c000 C:\Windows \system32\IPHLPAPI.DLL
0x74d20000 - 0x74d27000 C:\Windows \\ \\system32\WINNSI.DLL
0x70c60000 - 0x70c66000 C:\Windows \system32\rasadhlp.dll
0x71ba0000 - 0x71bd8000 C:\Windows \System32\fwpuclnt.dll
0x73930000 - 0x7393f000 C:\Program Files\Java\jdk1.7.0\jre\bin\\\
io.dll
0x04990000 - 0x049e5000 C:\Users\\\
barraille\AppData\Local \Temp\jna3666290841889849729.dll
VM参数:
jvm_args:-Djava.library.path = C:\Windows \System32 -Dfile.encoding = Cp1252
java_command:com.nbarraille.jspotify.main.Test
启动程序类型:SUN_STANDARD
环境变量:
PATH = C:/ Program Files / Java / jdk1.7.0 / bin / ../jre/bin/client;C:/Program Files / Java / jdk1.7.0 / bin /../ jre / bin; C:/ Program Files / Java / jdk1.7.0 / bin /../ jre / lib / i386; C:\Windows \System32
USERNAME = nbarraille
OS = Windows_NT
PROCESSOR_IDENTIFIER = x86 Family 6 Model 23 Stepping 10,GenuineIntel
---------------系统---------------
操作系统:Windows 7 Build 7600
CPU:total 2(每个CPU 2个核心,每个核心1个线程)系列6型号23步进10,cmov,cx8,fxsr,mmx,sse,sse2,sse3,ssse3,sse4.1
内存:4k页面,物理3624108k(885020k免费),交换7246452k(3637664k免费)
vm_info:用于Windows的Java HotSpot(TM)客户端VM(21.0-b01) -x86 JRE(1.7.0-ea-b129),建于2011年2月10日07:43:39由java_re与未知的MS VC ++:1600
时间:Mon Mar 07 14:25: 08 2011
已用时间:0秒
EDIT:
* 在C中测试API的代码
#includeapi.h
/ * ---数据--- * /
const uint8_t g_appkey [] = {/ * My appkey * /};
/ * ---------------------------会议呼叫------- ------------------ * /
static void logged_in(sp_session * sess,sp_error error){
printf(logged_in()called:\ n);
}
static void log_message(sp_session * sess,const char * data){
printf(log_message()called%s:\\\
,data);
}
static void notify_main_thread(sp_session * sess){
printf(notify_main_thread()called \\\
}
static sp_session_callbacks session_callbacks = {
//.logged_in =(void *)& logged_in,
//.notify_main_thread =(void *)& notify_main_thread,
//.log_message =(void *)& log_message,
};
static sp_session_config spconfig = {
.api_version = 7,
.cache_location =tmp,
.settings_location =tmp,
.application_key = g_appkey,
.application_key_size = sizeof(g_appkey),
.user_agent =jspotify,
.callbacks =& session_callbacks,
.userdata = NULL
} ;
int main(int argc,char ** argv)
{
sp_session * sp;
const char * username =foo;
const char * password =bar;
spconfig.application_key_size = sizeof(g_appkey);
printf(Creating session \\\
);
sp_error err = sp_session_create(& spconfig,& sp);
if(err!= 0){
printf(错误发生:%d \\\
,err);
return 0;
}
printf(Login \\\
);
sp_session_login(sp,username,password);
Sleep(10000);
return 0;
}
当我像这样(没有回调)运行时,输出是: / p>
创建会话
登录
当我注册回调(取消注释行),它甚至不打印任何东西!
当调用回调时打印任何东西,因为如果我注释 sp_session_login
行,只有 notify_main_thread
是唯一一个打印的)将阻止程序打印...
p>
struct Foo {
pre>
Bar * bar
}
ie一个包含指向另一个结构的指针,你的JNA实现Bar(
class Bar extends Structure
)也必须实现Structure.ByReference
interface - 否则JNA会认为struct Foo
包含struct Bar
的实例,而不是指向astruct Bar
,并且当C代码将Bar实例中的值解释为指针时,将导致非法的内存访问。
您需要向
$ b $感谢您启发我查看JNA - 非常酷!sp_session_callbacks
类添加实现Structure.ByReference
。
这段代码的输出是:
sp_session_create返回0
sp_session_login返回0
log_message()调用:14:16:53.825 I [ap:1388] ap.spotify.com:4070
log_message()调用:14:16:54.061 I [ap:938]连接到AP:193.182.8.11:4070
log_message )调用:14:16:54.765 E [ap:3396]连接错误:401
退出代码0
import com.sun.jna。*;
import com.sun.jna.ptr.PointerByReference;
import java.sql.Connection;
public class JNATest {
// static {
// System.loadLibrary(libspotify);
//}
public interface JLibspotify extends Library {
int sp_session_create(sp_session_config config,PointerByReference sess);
int sp_session_login(sp_session session,String username,String password);
//由API定义的所有其他方法
}
public static class sp_session extends PointerType {
public sp_session(Pointer address){
super(address);
}
public sp_session(){
super();
}
}
public static class sp_session_config extends Structure {
public int api_version = 7; //应用程序编译的Spotify API的版本。
public String cache_location =。;
public String settings_location =。;
public Pointer application_key; //您的应用程序键。
public int application_key_size; //应用程序键的大小(以字节为单位)
public String user_agent =jspotify;
public sp_session_callbacks callbacks; //交付会话事件的回调。 NULL如果不感兴趣任何回调
public Pointer userdata; //用户提供的应用程序数据
public boolean compress_playlists;
public boolean dont_save_metadata_for_playlists;
public boolean initial_unload_playlists;
}
public interface LoggedIn extends Callback {
public void logged_in(sp_session session,int error);
}
public interface LoggedOut extends Callback {
public void logged_out(sp_session session,int error);
}
public interface ConnectionError extends Callback {
public void connection_error(sp_session session,int error);
}
public static class sp_session_callbacks extends结构实现Structure.ByReference {
public LoggedIn logged_in; //在处理登录并成功时调用
public LoggedOut logged_out; //当注销被处理时调用。如果初始化注销操作,则显式调用;如果存在永久连接错误,则隐式调用。
public Callback metadata_updated; //每当元数据更新时调用。如果您的元数据在libspotify之外缓存,您应该清除缓存并获取新版本。
public ConnectionError connection_error; //在出现连接错误时调用,并且库在重新连接到Spotify服务时出现问题。可以多次调用(只要存在问题)
public Callback message_to_user; //当访问点要向用户显示消息时调用。在桌面客户端中,这些都显示在搜索框下方的蓝色工具栏中。
public Callback notify_main_thread; //当需要在主线程上进行处理时调用。你需要在主线程中调用sp_session_process_events()来获得libspotify做更多的工作。否则可能会导致请求超时或丢失连接。
public Callback music_delivery; //当有解压缩的音频数据可用时调用。
public Callback play_token_lost; //音乐已暂停,因为只有一个帐户可能会同时播放音乐。
public Callback log_message; //记录回调
public Callback end_of_track; //轨道结束。当当前播放的曲目到达结束时调用。
public Callback streaming_error; //流式传输错误。在流式传输时无法启动或继续时调用。
public Callback userinfo_updated; //在用户信息(与sp_user对象相关的任何内容)之后调用已更新。
public Callback start_playback; //在音频播放开始时调用。为了正常工作,应用程序还必须实现get_audio_buffer_stats()。此函数从内部会话线程调用 - 您需要有正确的同步。此函数不能阻止。
public Callback stop_playback; //在音频播放停止时调用。为了正常工作,应用程序还必须实现get_audio_buffer_stats()。此函数从内部会话线程调用 - 您需要有正确的同步。此函数不能阻止。
public Callback get_audio_buffer_stats; //调用查询应用程序有关其音频缓冲区。此函数从内部会话线程调用 - 您需要正确的同步!此函数不能阻止。
}
private static final char [] APP_KEY = {/ * Appkey here ** /;
public static void main(String [] args)throws InterruptedException {
JLibspotify lib =(JLibspotify)Native.loadLibrary(spotify,JLibspotify.class)
sp_session_config cfg = new sp_session_config();
Pointer ptr = new Memory(APP_KEY.length);
ptr.write(0,toBytes(APP_KEY),0,APP_KEY.length);
cfg.application_key = ptr;
cfg.application_key_size = APP_KEY.length;
sp_session_callbacks sessCallbacks = new sp_session_callbacks();
LoggedIn loggedInCallback = new LoggedIn(){
public void logged_in(sp_session session,int error){
System.out.println(logged_in()called);
}
};
ConnectionError connectionErrorCallback = new ConnectionError(){
public void connection_error(sp_session session,int error){
System.out.println(connection_error()called);
}
};
LoggedOut loggedOutCallback = new LoggedOut(){
public void logged_out(sp_session session,int error){
System.out.println(logged_out()called);
}
};
sessCallbacks.logged_in = loggedInCallback;
sessCallbacks.connection_error = connectionErrorCallback;
sessCallbacks.logged_out = loggedOutCallback;
sessCallbacks.log_message = new Callback(){
public void callback(sp_session session,String message){
System.out.println(log_message()called:+ message);
}
};
cfg.callbacks = sessCallbacks;
PointerByReference sessionPbr = new PointerByReference();
int error_id = lib.sp_session_create(cfg,sessionPbr); // CRASHES HERE
System.out.println(sp_session_create returned+ error_id);
//
sp_session mySession = new sp_session(sessionPbr.getValue());
error_id = lib.sp_session_login(mySession,foo,bar);
System.out.println(sp_session_login returned+ error_id);
Thread.sleep(1000);
}
public static byte [] toBytes(char [] key){
byte [] b = new byte [key.length];
for(int i = 0; iif(key [i]> 127){
b [i] =(byte [ i] -256);
} else {
b [i] =(byte)key [i];
}
}
return b;
}
}
这里是一个C程序,更少的回调 - 你需要添加更多)。它是为OS X所以你可能需要改变
#include
。由于我在澳大利亚无法获得spotify,我无法测试它是否一个成功的登录命中一个回调,但日志回调工作。#include< stdio.h>
#include< libspotify / api.h>
void SP_CALLCONV log_message(sp_session *session, const char *data) {
fprintf(stderr,\"log_message: %s\n\", data);
fflush(stderr);
}
void SP_CALLCONV connection_error(sp_session *session, sp_error error) {
fprintf(stderr,\"connection_error: %d\n\", error);
fflush(stderr);
}
int main(int argc, char** argv) {
static byte APP_KEY[] = {
/*the API key */};
static sp_session_callbacks callbacks;
callbacks.log_message = log_message;
callbacks.connection_error = connection_error;
static sp_session_config cfg;
cfg.callbacks = &callbacks;
cfg.api_version = 7;
cfg.cache_location = \".\";
cfg.settings_location = \".\";
cfg.user_agent = \"jspotify\";
cfg.application_key = APP_KEY;
cfg.application_key_size = sizeof(APP_KEY);
sp_session* mySession;
int code = sp_session_create(&cfg, &mySession);
printf(\"sp_session_create returned %d\n\", code);
sp_session_login(mySession, \"foo\", \"bar\");
printf(\"sp_session_login returned %d\n\", code);
sleep(10);
}
If the C program calls callbacks which the Java version doesn’t, then perhaps there’s something wrong with the use of jna -- if not, perhaps there’s something more to understand about spotify and when it calls callbacks. I agree that the docs seem to say that a successful login will call a callback, but perhaps they’re out of date?
I'm having problems handling callbacks in JNA.
I'm trying to use a C API that uses callbacks to handle several session events (logged in, logged out, connection problem...).
The session object (calledsp_session
) is an opaque struct. All the callbacks are registered in asp_session_callbacks
structure. According to the API, I am supposed to declare the callbacks object, and put it into a Config object that I will provide when creating thesp_session
object. If I don't want to use certain callbacks, I am supposed to initialize them withnull
. The API is using the__stdcall
calling convention.Here is a snippet of the C header that's relevant to my problem:
#define SP_CALLCONV __stdcall typedef struct sp_session sp_session; ///< Representation of a session typedef enum sp_error { SP_ERROR_OK = 0, SP_ERROR_BAD_API_VERSION = 1, /* More errors */ } sp_error; typedef struct sp_session_callbacks { /** * Called when login has been processed and was successful */ void (SP_CALLCONV *logged_in)(sp_session *session, sp_error error); /** * Called when logout has been processed. Either called explicitly * if you initialize a logout operation, or implicitly if there * is a permanent connection error * * @param[in] session Session */ void (SP_CALLCONV *logged_out)(sp_session *session); /** * Called when there is a connection error, and the library has problems * reconnecting to the Spotify service. Could be called multiple times (as * long as the problem is present) */ void (SP_CALLCONV *connection_error)(sp_session *session, sp_error error); /* More callbacks */ } sp_session_callbacks; /** * Initialize a session. The session returned will be initialized, but you will need * to log in before you can perform any other operation */ SP_LIBEXPORT(sp_error) sp_session_create(const sp_session_config *config, sp_session **sess);
Here is my equivalent JNA code:
The sp_session object
public class sp_session extends PointerType{ public sp_session(Pointer address) { super(address); } public sp_session() { super(); } }
The sp_session_callbacks object, containing all the callbacks
public class sp_session_callbacks extends Structure{ public LoggedIn logged_in; public LoggedOut logged_out; public ConnectionError connection_error; }
The callbacks object (here is LoggedIn, but of course I have one for each callback)
public interface LoggedIn extends StdCallCallback { public void logged_in(sp_session session, int error); }
The native library, with the declaration of all the methods
public interface JLibspotify extends StdCallLibrary{ int sessionCreate(sp_session_config config, PointerByReference sess); int sessionLogin(sp_session session, String username, String password); // All the other methods defined by the API }
And my main class, binding it all together
public class Test{ static{ System.loadLibrary("libspotify"); } public static void main(String[] args){ JLibspotify lib = (JLibspotify)Native.loadLibrary("libspotify", JLibspotify.class); sp_session_config cfg = new sp_session_config(); } sp_session_callbacks sessCallbacks = new sp_session_callbacks(); LoggedIn loggedInCallback = new LoggedIn(){ public void logged_in(sp_session session, int error) { System.out.println("logged_in() called"); } }; sessCallbacks.logged_in = loggedInCallback; cfg.session_callbacks = sessCallbacks; PointerByReference sessionPbr = new PointerByReference(); int error_id = sessionCreate(cfg, sessionPbr); // CRASHES HERE sp_session mySession = new sp_session(sessionPbr.getValue()); } }
So, the sessionCreate function call makes the JRE crash with the trace at the end of the post
EXCEPTION_ACCESS_VIOLATION (0xc0000005) problematic frame: C [jna3666290841889849729.dll+0xa3f4]
.It looks like the logged_in callback is causing this, because when I set it to
null
it runs ok. Plus, if I initialize theconnection_error
callback, that has the exact same signature, it doesn't crash either.I'm running version 3.2.7 of JNA. I tried with an anterior version (3.0.9) and it also failed. I'm running the JDK 1.7 beta version, but I tried with the 1.6 and it also failed.
Thank you!
# # A fatal error has been detected by the Java Runtime Environment: # # EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x0499a3f4, pid=1368, tid=1344 # # JRE version: 7.0-b129 # Java VM: Java HotSpot(TM) Client VM (21.0-b01 mixed mode, sharing windows-x86 ) # Problematic frame: # C [jna3666290841889849729.dll+0xa3f4] # # If you would like to submit a bug report, please visit: # http://java.sun.com/webapps/bugreport/crash.jsp # The crash happened outside the Java Virtual Machine in native code. # See problematic frame for where to report the bug. # --------------- T H R E A D --------------- Current thread (0x01b79400): JavaThread "main" [_thread_in_native, id=1344, stack(0x00340000,0x00390000)] siginfo: ExceptionCode=0xc0000005, reading address 0x1993053a Registers: EAX=0x19930522, EBX=0x100dc77c, ECX=0x00010004, EDX=0x1008d3e0 ESP=0x0038f58c, EBP=0x0038f5b4, ESI=0x0038f5a4, EDI=0x100b79b0 EIP=0x0499a3f4, EFLAGS=0x00210212 Top of Stack: (sp=0x0038f58c) 0x0038f58c: 100dc77c 0038f5a4 00010004 0038f688 0x0038f59c: 05983de0 05981330 0598289c 05983de0 0x0038f5ac: 05983de0 00000014 0038f688 1008d3ea 0x0038f5bc: 05983de0 10030d77 0038fc44 100b79b0 0x0038f5cc: ffffffff 1008d334 00000000 05983de0 0x0038f5dc: 1008d3e0 05983fc4 1008d9fd 0038f770 0x0038f5ec: 00000000 00000000 7275016a 055310b0 0x0038f5fc: 00000000 00010001 00000000 00000000 Instructions: (pc=0x0499a3f4) 0x0499a3d4: 01 00 89 e5 57 56 8d 75 f0 53 83 ec 1c 8b 7d 14 0x0499a3e4: 8b 5f 4c 8b 03 89 4c 24 08 89 74 24 04 89 1c 24 0x0499a3f4: ff 50 18 83 ec 0c 85 c0 0f 94 c0 0f b6 c0 85 c0 0x0499a404: 89 45 ec 75 19 8b 03 31 d2 89 54 24 08 89 74 24 Register to memory mapping: EAX=0x19930522 is an unknown value EBX=0x100dc77c is an unknown value ECX=0x00010004 is an unknown value EDX=0x1008d3e0 is an unknown value ESP=0x0038f58c is pointing into the stack for thread: 0x01b79400 EBP=0x0038f5b4 is pointing into the stack for thread: 0x01b79400 ESI=0x0038f5a4 is pointing into the stack for thread: 0x01b79400 EDI=0x100b79b0 is an unknown value Stack: [0x00340000,0x00390000], sp=0x0038f58c, free space=317k Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code) C [jna3666290841889849729.dll+0xa3f4] Java_com_sun_jna_Native_initialize_1ffi_1type+0x1054 C [libspotify.dll+0x8d3ea] sp_error_message+0x35a C [jna3666290841889849729.dll+0xcb77] Java_com_sun_jna_Native_initialize_1ffi_1type+0x37d7 C [jna3666290841889849729.dll+0xc7c2] Java_com_sun_jna_Native_initialize_1ffi_1type+0x3422 C [jna3666290841889849729.dll+0x4561] Java_com_sun_jna_Pointer__1getString+0xa31 C [jna3666290841889849729.dll+0x4d2e] Java_com_sun_jna_Function_invokeInt+0x2e j com.sun.jna.Function.invokeInt(I[Ljava/lang/Object;)I+0 j com.sun.jna.Function.invoke([Ljava/lang/Object;Ljava/lang/Class;Z)Ljava/lang/Object;+315 j com.sun.jna.Function.invoke(Ljava/lang/Class;[Ljava/lang/Object;Ljava/util/Map;)Ljava/lang/Object;+214 j com.sun.jna.Library$Handler.invoke(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;+341 j $Proxy0.sp_session_create(Lcom/nbarraille/jspotify/model/sp_session_config;Lcom/sun/jna/ptr/PointerByReference;)I+20 j com.nbarraille.jspotify.main.Test.main([Ljava/lang/String;)V+273 v ~StubRoutines::call_stub V [jvm.dll+0x115f6d] V [jvm.dll+0x1b788e] V [jvm.dll+0x115fed] V [jvm.dll+0xa2507] V [jvm.dll+0xac867] C [javaw.exe+0x209e] C [javaw.exe+0xa23b] C [javaw.exe+0xa2c5] C [kernel32.dll+0x51194] BaseThreadInitThunk+0x12 C [ntdll.dll+0x5b429] RtlInitializeExceptionChain+0x63 C [ntdll.dll+0x5b3fc] RtlInitializeExceptionChain+0x36 Java frames: (J=compiled Java code, j=interpreted, Vv=VM code) j com.sun.jna.Function.invokeInt(I[Ljava/lang/Object;)I+0 j com.sun.jna.Function.invoke([Ljava/lang/Object;Ljava/lang/Class;Z)Ljava/lang/Object;+315 j com.sun.jna.Function.invoke(Ljava/lang/Class;[Ljava/lang/Object;Ljava/util/Map;)Ljava/lang/Object;+214 j com.sun.jna.Library$Handler.invoke(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;+341 j $Proxy0.sp_session_create(Lcom/nbarraille/jspotify/model/sp_session_config;Lcom/sun/jna/ptr/PointerByReference;)I+20 j com.nbarraille.jspotify.main.Test.main([Ljava/lang/String;)V+273 v ~StubRoutines::call_stub --------------- P R O C E S S --------------- Java Threads: ( => current thread ) 0x0182fc00 JavaThread "Low Memory Detector" daemon [_thread_blocked, id=4664, stack(0x04170000,0x041c0000)] 0x0182ac00 JavaThread "C1 CompilerThread0" daemon [_thread_blocked, id=1728, stack(0x01b20000,0x01b70000)] 0x01829800 JavaThread "Attach Listener" daemon [_thread_blocked, id=112, stack(0x04020000,0x04070000)] 0x01826400 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=5836, stack(0x03ea0000,0x03ef0000)] 0x01819800 JavaThread "Finalizer" daemon [_thread_blocked, id=4724, stack(0x03f80000,0x03fd0000)] 0x01817800 JavaThread "Reference Handler" daemon [_thread_blocked, id=3940, stack(0x01ad0000,0x01b20000)] =>0x01b79400 JavaThread "main" [_thread_in_native, id=1344, stack(0x00340000,0x00390000)] Other Threads: 0x01816400 VMThread [stack: 0x01a30000,0x01a80000] [id=3876] 0x01843000 WatcherThread [stack: 0x040d0000,0x04120000] [id=4636] VM state:not at safepoint (normal execution) VM Mutex/Monitor currently owned by a thread: None Heap def new generation total 4928K, used 3630K [0x23450000, 0x239a0000, 0x289a0000) eden space 4416K, 82% used [0x23450000, 0x237db858, 0x238a0000) from space 512K, 0% used [0x238a0000, 0x238a0000, 0x23920000) to space 512K, 0% used [0x23920000, 0x23920000, 0x239a0000) tenured generation total 10944K, used 0K [0x289a0000, 0x29450000, 0x33450000) the space 10944K, 0% used [0x289a0000, 0x289a0000, 0x289a0200, 0x29450000) compacting perm gen total 12288K, used 860K [0x33450000, 0x34050000, 0x37450000) the space 12288K, 7% used [0x33450000, 0x33527190, 0x33527200, 0x34050000) ro space 10240K, 43% used [0x37450000, 0x3789ce40, 0x3789d000, 0x37e50000) rw space 12288K, 53% used [0x37e50000, 0x384c2710, 0x384c2800, 0x38a50000) Code Cache [0x01e90000, 0x01f20000, 0x03e90000) total_blobs=234 nmethods=82 adapters=88 free_code_cache=32972224 largest_free_block=0 Dynamic libraries: 0x00880000 - 0x008b0000 C:\Program Files\Java\jdk1.7.0\bin\javaw.exe 0x778f0000 - 0x77a2d000 C:\Windows\SYSTEM32\ntdll.dll 0x77070000 - 0x77144000 C:\Windows\system32\kernel32.dll 0x75cf0000 - 0x75d3a000 C:\Windows\system32\KERNELBASE.dll 0x60000000 - 0x60041000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\midas32.dll 0x61000000 - 0x61028000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\plugin_base.m32 0x67000000 - 0x67048000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\plugin_nt.m32 0x64000000 - 0x64021000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\plugin_registry.m32 0x62000000 - 0x6202d000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\plugin_extra.m32 0x65000000 - 0x6501a000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\plugin_net.m32 0x63000000 - 0x630a6000 C:\Program Files\BitDefender\BitDefender 2011\Active Virus Control\Midas_00078_002\plugin_fragments.m32 0x75e10000 - 0x75eb0000 C:\Windows\system32\ADVAPI32.dll 0x775c0000 - 0x7766c000 C:\Windows\system32\msvcrt.dll 0x75d50000 - 0x75d69000 C:\Windows\SYSTEM32\sechost.dll 0x77670000 - 0x77711000 C:\Windows\system32\RPCRT4.dll 0x76f00000 - 0x76fc9000 C:\Windows\system32\USER32.dll 0x77a50000 - 0x77a9e000 C:\Windows\system32\GDI32.dll 0x77a30000 - 0x77a3a000 C:\Windows\system32\LPK.dll 0x75d70000 - 0x75e0d000 C:\Windows\system32\USP10.dll 0x74830000 - 0x749ce000 C:\Windows\WinSxS\x86_microsoft.windows.common-controls_6595b64144ccf1df_6.0.7600.16661_none_420fe3fa2b8113bd\COMCTL32.dll 0x772f0000 - 0x77347000 C:\Windows\system32\SHLWAPI.dll 0x775a0000 - 0x775bf000 C:\Windows\system32\IMM32.DLL 0x75eb0000 - 0x75f7c000 C:\Windows\system32\MSCTF.dll 0x72740000 - 0x727fe000 C:\Program Files\Java\jdk1.7.0\jre\bin\msvcr100.dll 0x01b80000 - 0x01e89000 C:\Program Files\Java\jdk1.7.0\jre\bin\client\jvm.dll 0x746c0000 - 0x746f2000 C:\Windows\system32\WINMM.dll 0x73920000 - 0x7392c000 C:\Program Files\Java\jdk1.7.0\jre\bin\verify.dll 0x73330000 - 0x73350000 C:\Program Files\Java\jdk1.7.0\jre\bin\java.dll 0x75d40000 - 0x75d45000 C:\Windows\system32\PSAPI.DLL 0x733a0000 - 0x733b3000 C:\Program Files\Java\jdk1.7.0\jre\bin\zip.dll 0x10000000 - 0x10259000 C:\Windows\System32\libspotify.dll 0x77150000 - 0x77185000 C:\Windows\system32\WS2_32.dll 0x77a40000 - 0x77a46000 C:\Windows\system32\NSI.dll 0x75ba0000 - 0x75cbc000 C:\Windows\system32\CRYPT32.dll 0x75ab0000 - 0x75abc000 C:\Windows\system32\MSASN1.dll 0x74ee0000 - 0x74f38000 C:\Windows\system32\WINHTTP.dll 0x74e90000 - 0x74edf000 C:\Windows\system32\webio.dll 0x754c0000 - 0x754d6000 C:\Windows\system32\CRYPTSP.dll 0x75260000 - 0x7529b000 C:\Windows\system32\rsaenh.dll 0x750a0000 - 0x750b7000 C:\Windows\system32\USERENV.dll 0x75a40000 - 0x75a4b000 C:\Windows\system32\profapi.dll 0x75a30000 - 0x75a3c000 C:\Windows\system32\CRYPTBASE.dll 0x728a0000 - 0x728b6000 C:\Program Files\Java\jdk1.7.0\jre\bin\net.dll 0x75480000 - 0x754bc000 C:\Windows\system32\mswsock.dll 0x75470000 - 0x75476000 C:\Windows\System32\wship6.dll 0x73950000 - 0x73960000 C:\Windows\system32\NLAapi.dll 0x75340000 - 0x75384000 C:\Windows\system32\DNSAPI.dll 0x71030000 - 0x71038000 C:\Windows\System32\winrnr.dll 0x71020000 - 0x71030000 C:\Windows\system32\napinsp.dll 0x71000000 - 0x71012000 C:\Windows\system32\pnrpnsp.dll 0x74fd0000 - 0x74fd5000 C:\Windows\System32\wshtcpip.dll 0x74d30000 - 0x74d4c000 C:\Windows\system32\IPHLPAPI.DLL 0x74d20000 - 0x74d27000 C:\Windows\system32\WINNSI.DLL 0x70c60000 - 0x70c66000 C:\Windows\system32\rasadhlp.dll 0x71ba0000 - 0x71bd8000 C:\Windows\System32\fwpuclnt.dll 0x73930000 - 0x7393f000 C:\Program Files\Java\jdk1.7.0\jre\bin\nio.dll 0x04990000 - 0x049e5000 C:\Users\nbarraille\AppData\Local\Temp\jna3666290841889849729.dll VM Arguments: jvm_args: -Djava.library.path=C:\Windows\System32 -Dfile.encoding=Cp1252 java_command: com.nbarraille.jspotify.main.Test Launcher Type: SUN_STANDARD Environment Variables: PATH=C:/Program Files/Java/jdk1.7.0/bin/../jre/bin/client;C:/Program Files/Java/jdk1.7.0/bin/../jre/bin;C:/Program Files/Java/jdk1.7.0/bin/../jre/lib/i386;C:\Windows\System32 USERNAME=nbarraille OS=Windows_NT PROCESSOR_IDENTIFIER=x86 Family 6 Model 23 Stepping 10, GenuineIntel --------------- S Y S T E M --------------- OS: Windows 7 Build 7600 CPU:total 2 (2 cores per cpu, 1 threads per core) family 6 model 23 stepping 10, cmov, cx8, fxsr, mmx, sse, sse2, sse3, ssse3, sse4.1 Memory: 4k page, physical 3624108k(885020k free), swap 7246452k(3637664k free) vm_info: Java HotSpot(TM) Client VM (21.0-b01) for windows-x86 JRE (1.7.0-ea-b129), built on Feb 10 2011 07:43:39 by "java_re" with unknown MS VC++:1600 time: Mon Mar 07 14:25:08 2011 elapsed time: 0 seconds
EDIT: *Code to test the API in C*
#include "api.h" /* --- Data --- */ const uint8_t g_appkey[] = {/*My appkey*/}; /* --------------------------- SESSION CALLBACKS ------------------------- */ static void logged_in(sp_session *sess, sp_error error){ printf("logged_in() called: \n"); } static void log_message(sp_session *sess, const char *data){ printf("log_message() called %s : \n", data); } static void notify_main_thread(sp_session *sess){ printf("notify_main_thread() called \n"); } static sp_session_callbacks session_callbacks = { //.logged_in = (void*)&logged_in, //.notify_main_thread = (void*)¬ify_main_thread, //.log_message = (void*)&log_message, }; static sp_session_config spconfig = { .api_version = 7, .cache_location = "tmp", .settings_location = "tmp", .application_key = g_appkey, .application_key_size = sizeof(g_appkey), .user_agent = "jspotify", .callbacks = &session_callbacks, .userdata = NULL }; int main(int argc, char **argv) { sp_session *sp; const char *username = "foo"; const char *password = "bar"; spconfig.application_key_size = sizeof(g_appkey); printf("Creating session \n"); sp_error err = sp_session_create(&spconfig, &sp); if(err != 0){ printf("Error occured: %d \n", err); return 0; } printf("Login\n"); sp_session_login(sp, username, password); Sleep(10000); return 0; }
When I run it like this (without callbacks), the output is:
Creating session Login
And when I register the callbacks (uncomment the lines), it doesn't even print anything!
It looks like it doesn't print anything when a callback is called, because if I comment the
sp_session_login
line, only the declaration ofnotify_main_thread
(which is the only one printed) will prevent the program from printing...解决方案When you have a C structure like:
struct Foo { Bar* bar }
i.e. one which contains a pointer to another structure, your JNA implementation of Bar (
class Bar extends Structure
) must also implement theStructure.ByReference
interface -- otherwise JNA will think thatstruct Foo
contains an instance ofstruct Bar
instead of a pointer to astruct Bar
, and an illegal memory access will result as the C code interprets a value in the Bar instance as a pointer.You need to add
implements Structure.ByReference
to thesp_session_callbacks
class.Thanks for inspiring me to look at JNA -- it's pretty cool!
Output of this code is:
sp_session_create returned 0 sp_session_login returned 0 log_message() called:14:16:53.825 I [ap:1388] Connecting to AP ap.spotify.com:4070 log_message() called:14:16:54.061 I [ap:938] Connected to AP: 193.182.8.11:4070 log_message() called:14:16:54.765 E [ap:3396] Connection error: 401
Process finished with exit code 0
import com.sun.jna.*; import com.sun.jna.ptr.PointerByReference; import java.sql.Connection; public class JNATest { // static { // System.loadLibrary("libspotify"); // } public interface JLibspotify extends Library { int sp_session_create(sp_session_config config, PointerByReference sess); int sp_session_login(sp_session session, String username, String password); // All the other methods defined by the API } public static class sp_session extends PointerType { public sp_session(Pointer address) { super(address); } public sp_session() { super(); } } public static class sp_session_config extends Structure { public int api_version = 7; // The version of the Spotify API your application is compiled with. public String cache_location = "."; public String settings_location = "."; public Pointer application_key; // Your application key. public int application_key_size; // The size of the application key in bytes public String user_agent = "jspotify"; public sp_session_callbacks callbacks; // Delivery callbacks for session events. NULL if not interested in any callbacks public Pointer userdata; // User supplied data for your application public boolean compress_playlists; public boolean dont_save_metadata_for_playlists; public boolean initially_unload_playlists; } public interface LoggedIn extends Callback { public void logged_in(sp_session session, int error); } public interface LoggedOut extends Callback { public void logged_out(sp_session session, int error); } public interface ConnectionError extends Callback { public void connection_error(sp_session session, int error); } public static class sp_session_callbacks extends Structure implements Structure.ByReference{ public LoggedIn logged_in; // Called when login has been processed and was successful public LoggedOut logged_out; // Called when logout has been processded. Either called explicitly if you initialize a logout operation, or implicitly if there is a permanent connection error. public Callback metadata_updated; // Called whenever metadata has been updated. If you have metadata cached outside of libspotify, you should purge your caches and fetch new versions. public ConnectionError connection_error; // Called when there is a connection error, and the library has problems reconnecting to the Spotify service. Could be called multiple times (as long as the problem is present) public Callback message_to_user; // Called when the acces point wants to display a message to the user. In the desktop client, these are shown in a blueish toolbar just below the search box. public Callback notify_main_thread; // Called when processing needs to take place on the main thread. You need to call sp_session_process_events() in the main thread to get libspotify to do more work. Failure to do so may cause request timeouts, or a lost connections. public Callback music_delivery; // Called when there is decompressed audio data available. public Callback play_token_lost; // Music has been paused because only one account may play music at the same time. public Callback log_message; // Logging callback public Callback end_of_track; // End of track. Called when the currently played track has reached its end. public Callback streaming_error; // Streaming error. Called when streaming cannot start or continue. public Callback userinfo_updated; // Called after user info (anything related to sp_user objects) have been updated. public Callback start_playback; // Called when audio playback should start. For this to work correctly the application must also implement get_audio_buffer_stats(). This function is called from an internal session thread - you need to have proper synchronization. This function must never block. public Callback stop_playback; // Called when audio playback should stop. For this to work correctly the application must also implement get_audio_buffer_stats(). This function is called from an internal session thread - you need to have proper synchronization. This function must never block. public Callback get_audio_buffer_stats; // Called to query application about its audio buffer. This function is called from an internal session thread - you need to have proper synchronization! This function must never block. } private static final char[] APP_KEY ={/* Appkey here**/; public static void main(String[] args) throws InterruptedException { JLibspotify lib = (JLibspotify) Native.loadLibrary("spotify", JLibspotify.class); sp_session_config cfg = new sp_session_config(); Pointer ptr = new Memory(APP_KEY.length); ptr.write(0, toBytes(APP_KEY), 0, APP_KEY.length); cfg.application_key = ptr; cfg.application_key_size = APP_KEY.length; sp_session_callbacks sessCallbacks = new sp_session_callbacks(); LoggedIn loggedInCallback = new LoggedIn() { public void logged_in(sp_session session, int error) { System.out.println("logged_in() called"); } }; ConnectionError connectionErrorCallback = new ConnectionError() { public void connection_error(sp_session session, int error) { System.out.println("connection_error() called"); } }; LoggedOut loggedOutCallback = new LoggedOut() { public void logged_out(sp_session session, int error) { System.out.println("logged_out() called"); } }; sessCallbacks.logged_in = loggedInCallback; sessCallbacks.connection_error = connectionErrorCallback; sessCallbacks.logged_out = loggedOutCallback; sessCallbacks.log_message = new Callback() { public void callback(sp_session session, String message) { System.out.println("log_message() called:" + message); } }; cfg.callbacks = sessCallbacks; PointerByReference sessionPbr = new PointerByReference(); int error_id = lib.sp_session_create(cfg, sessionPbr); // CRASHES HERE System.out.println("sp_session_create returned " + error_id); // sp_session mySession = new sp_session(sessionPbr.getValue()); error_id = lib.sp_session_login(mySession, "foo", "bar"); System.out.println("sp_session_login returned " + error_id); Thread.sleep(1000); } public static byte[] toBytes(char[] key){ byte[] b = new byte[key.length]; for(int i =0; i < key.length; i++){ if(key[i] > 127){ b[i] = (byte)(key[i] - 256); }else{ b[i] = (byte)key[i]; } } return b; } }
Here's a C program which does the same thing (with fewer callbacks -- you'll need to add more). It's for OS X so you may need to change the
#include
. As I can't get spotify in Australia I can't test it to see whether a successful login hits a callback, but the logging callback works.#include <stdio.h> #include <libspotify/api.h> void SP_CALLCONV log_message(sp_session *session, const char *data) { fprintf(stderr,"log_message: %s\n", data); fflush(stderr); } void SP_CALLCONV connection_error(sp_session *session, sp_error error) { fprintf(stderr,"connection_error: %d\n", error); fflush(stderr); } int main(int argc, char** argv) { static byte APP_KEY[] = { /*the API key */}; static sp_session_callbacks callbacks; callbacks.log_message = log_message; callbacks.connection_error = connection_error; static sp_session_config cfg; cfg.callbacks = &callbacks; cfg.api_version = 7; cfg.cache_location = "."; cfg.settings_location = "."; cfg.user_agent = "jspotify"; cfg.application_key = APP_KEY; cfg.application_key_size = sizeof(APP_KEY); sp_session* mySession; int code = sp_session_create(&cfg, &mySession); printf("sp_session_create returned %d\n", code); sp_session_login(mySession, "foo", "bar"); printf("sp_session_login returned %d\n", code); sleep(10); }
If the C program calls callbacks which the Java version doesn't, then perhaps there's something wrong with the use of jna -- if not, perhaps there's something more to understand about spotify and when it calls callbacks. I agree that the docs seem to say that a successful login will call a callback, but perhaps they're out of date?
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