惊讶有趣的事情
1、gdb调试无任何有用信息
1-1、CMake添加-g编译选项/CMake编译Debug版本
在文件 CMakeLists.txt添加下面一条语句
add_definitions("-Wall -g")
命令行配置
cmake -DCMAKE_BUILD_TYPE=Debug ..
1-2、coredump文件配置
cat /proc/sys/kernel/core_pattern
| /usr/local/bin/gzip_core_dump.sh /other/core/%e.core.%s.%p
gzip_core_dump.sh
#!/bin/bash
/bin/cat > "$1"
#/bin/gzip > "$1"
1-3、gdb调试无任何有用信息
gdb example example.core.7.30798
or
gdb example & r
正常的情况：
root@adesk:~# ldd example
linux-vdso.so.1 (0x00007fff8350d000)
libuvc.so.0 => /usr/lib/libuvc.so.0 (0x00007fc28893a000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fc28871d000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fc28837e000)
libusb-1.0.so.0 => /usr/local/lib/libusb-1.0.so.0 (0x00007fc288167000)
libjpeg.so.62 => /usr/local/lib/libjpeg.so.62 (0x00007fc287eff000)
/lib64/ld-linux-x86-64.so.2 (0x00007fc288b4e000)
libudev.so.1 => /lib/x86_64-linux-gnu/libudev.so.1 (0x00007fc288d38000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007fc287cf7000)
root@adesk:~# rm /usr/lib/libuvc.so.0
root@adesk:~# ldd example
linux-vdso.so.1 (0x00007ffcc776f000)
libuvc.so.0 => not found
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f8e1ffbd000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f8e1fc1e000)
/lib64/ld-linux-x86-64.so.2 (0x00007f8e201da000)
异常的情况：
root@adesk:~# ldd libuvc.so.0
ldd: exited with unknown exit code (135)
root@adesk:~# file libuvc.so.0
libuvc.so.0: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, missing section headers
root@adesk:~# readelf libuvc.so.0 -h
ELF Header:
Magic: 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: Advanced Micro Devices X86-64
Version: 0x1
Entry point address: 0x4a60
Start of program headers: 64 (bytes into file)
Start of section headers: 91504 (bytes into file)
Flags: 0x0
Size of this header: 64 (bytes)
Size of program headers: 56 (bytes)
Number of program headers: 6
Size of section headers: 64 (bytes)
Number of section headers: 29
Section header string table index: 26
readelf: Error: Reading 0x740 bytes extends past end of file for section headers
readelf: Error: the dynamic segment offset + size exceeds the size of the file
root@adesk:~# ldd example
root@adesk:~# nm libuvc.so.0
nm: libuvc.so.0: File truncated
root@adesk:~# ./example
Bus error (core dumped)
(gdb) bt
#0 0x00007ffff7df4d41 in ?? () from /lib64/ld-linux-x86-64.so.2
#1 0x00007ffff7ddf406 in ?? () from /lib64/ld-linux-x86-64.so.2
#2 0x00007ffff7de180c in ?? () from /lib64/ld-linux-x86-64.so.2
#3 0x00007ffff7de6080 in ?? () from /lib64/ld-linux-x86-64.so.2
#4 0x00007ffff7de8704 in ?? () from /lib64/ld-linux-x86-64.so.2
#5 0x00007ffff7de62ef in ?? () from /lib64/ld-linux-x86-64.so.2
#6 0x00007ffff7ddc6c2 in ?? () from /lib64/ld-linux-x86-64.so.2
#7 0x00007ffff7df085e in ?? () from /lib64/ld-linux-x86-64.so.2
#8 0x00007ffff7ddaae8 in ?? () from /lib64/ld-linux-x86-64.so.2
#9 0x00007ffff7dd9c28 in ?? () from /lib64/ld-linux-x86-64.so.2
#10 0x0000000000000001 in ?? ()
#11 0x00007fffffffedcb in ?? ()
#12 0x0000000000000000 in ?? ()
结论：损坏的ELF库文件，程序链接到损坏的so文件后，自身也会发生莫名其妙的化学反应。 https://blog.csdn.net/epubit17/article/details/121138474
2、微软程序匹配很迷糊
D:\Github\Storage\batch>devcon find "USB*4*"
USB\ROOT_HUB\4&F9F7C6&0 : USB Root Hub
USB\ROOT_HUB\4&2002FA77&0 : USB Root Hub
2 matching device(s) found.
D:\Github\Storage\batch>devcon find "USB*"
USB\ROOT_HUB\4&32218256&0 : USB Root Hub
USB\ROOT_HUB\4&36880E1&0 : USB Root Hub
USB\ROOT_HUB\4&F9F7C6&0 : USB Root Hub
USB\ROOT_HUB20\4&2ACC3A04&0 : USB Root Hub
USB\ROOT_HUB20\4&326BD9DE&0 : USB Root Hub
USB\ROOT_HUB\4&17BD5F01&0 : USB Root Hub
USB\ROOT_HUB\4&192D568&0 : USB Root Hub
USB\ROOT_HUB\4&1CB239E3&0 : USB Root Hub
USB\ROOT_HUB\4&2002FA77&0 : USB Root Hub
9 matching device(s) found.