我正在尝试使用jnr-ffi与 C 库libzbc交互。第一个函数调用zbc_open起作用并返回一个指向打开设备的指针。然后下一次调用zbc_get_device_info会导致 JVM 崩溃。
原因是什么?如何解决? 我认为错误出现在 zbc 的接口或我的传递参数中,但搜索 JNR 的任何文档在 google 中没有产生任何有用的结果。如果我在结构中省略数组部分,也会发生崩溃。
我使用jnr-fuse项目作为起点,因为我的目标是编写一个 FUSE 文件系统。
C函数:
void zbc_set_log_level( char *log_level )
int zbc_open (const char *filename, int flags, struct zbc_device **dev)
void zbc_get_device_info( struct zbc_device *dev, struct zbc_device_info * info)
C 结构 zbc_device_info:
enum zbc_dev_type zbd_type
enum zbc_dev_model zbd_model
char zbd_vendor_id [ZBC_DEVICE_INFO_LENGTH]
uint32_t zbd_flags
uint64_t zbd_sectors
uint32_t zbd_lblock_size
uint64_t zbd_lblocks
uint32_t zbd_pblock_size
uint64_t zbd_pblocks
uint64_t zbd_max_rw_sectors
uint32_t zbd_opt_nr_open_seq_pref
uint32_t zbd_opt_nr_non_seq_write_seq_pref
uint32_t zbd_max_nr_open_seq_req
JNR接口:
public interface zbc{
public void zbc_set_log_level(String level);
public int zbc_open(String filename,int flags, PointerByReference p);
public void zbc_get_device_info(Pointer dev,zbc_device_info info);
}
public static class zbc_device_info extends Struct {
int zbd_type;
int zbd_model;
byte zbd_vendor_id[]=new byte[32];
u_int32_t zbd_flags;
u_int64_t zbd_sectors;
u_int32_t zbd_lblock_size;
u_int64_t zbd_lblocks;
u_int32_t zbd_pblock_size;
u_int64_t zbd_pblocks;
u_int64_t zbd_max_rw_sectors;
u_int32_t zbd_opt_nr_open_seq_pref;
u_int32_t zbd_opt_nr_non_seq_write_seq_pref;
u_int32_t zbd_max_nr_open_seq_pref;
protected zbc_device_info(Runtime runtime) {
super(runtime);
}
}
主要功能:
public static void main(String[] args) {
zbc z = LibraryLoader.create(zbc.class).load("zbc");
Runtime runtime=Runtime.getRuntime(z);
z.zbc_set_log_level("debug");
PointerByReference pr = new PointerByReference();
int ret=z.zbc_open("/temp/test.img", IO_RDWR,pr);
zbc_device_info info=new zbc_device_info(runtime);
z.zbc_get_device_info(pr.getValue(),info);
}
JVM崩溃:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x00007fa794300c70, pid=29106, tid=0x00007fa7bd4a4700
#
# JRE version: OpenJDK Runtime Environment (8.0_131-b11) (build 1.8.0_131-8u131-b11-2ubuntu1.16.04.3-b11)
# Java VM: OpenJDK 64-Bit Server VM (25.131-b11 mixed mode linux-amd64 compressed oops)
# Problematic frame:
# C [jffi6917022509387828651.so+0x5c70] jffi_releaseArrays+0x60
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
# /home/mmmm/jnr-fuse/hs_err_pid29106.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.java.com/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#