Android下用gdb遠端偵錯辦法

 　　Host: ubuntu

　　Target: Android ICS

　　1. 將gdbserver和gdbclient分別放入target和host。兩者都可在android原始碼的prebuilt目錄下找到。

　　2. 在Target上啟動gdbserver，在adb shell中執行

　　$ /path/to/gdbserver :1111--attach PID

　　其中PID為想要debug程式的進程號，可以通過ps得到。1111為連接埠號碼，可以自訂。

　　3. 在Host上啟動gdbclient，首先將target上的庫pull到host上(如/home/jzj/debug/gdb)

　　$cd /home/jzj/debug/gdb

　　$adb pull /system/lib

　　$adb pull /system/bin/app_process

　　然後寫啟動指令碼init.gdb(這裡假設程式要用到的庫放在/home/jzj/debug/gdb/下，android的symbol放在/home/jzj/debug/ics/symbols/system/lib/下，android的源碼放在/home/jzj/workspace/ics下)

　　file /home/jzj/debug/gdb/app_process

　　set solib-absolute-prefix /home/jzj/debug/ics/symbols/

　　set solib-search-path /home/jzj/debug/ics/symbols/system/lib/:/home/jzj/debug/gdb

　　dir /home/jzj/workspace/ics

　　shell adb forward tcp:1111 tcp:1111

　　target remote :1111

　　最後執行

　　$ gdb -x init.gdb

　　就可以啟動gdb了。一切正常的話這時候就可以用gdb的準系統，如設斷點或者查看記憶體了。這時有些so庫的符號表可能還沒載入，可以執行

　　(gdb) shared

　　載入這些符號表。

　　最後附個關於gdb設定指令碼中兩個變數的官方解釋，一般solib-absolute-prefix先於solib-search-path尋找。

　　solib-absolute-prefix ：

　　If this variable is set, path will be used as a prefix for any absolute shared library paths; many runtime loaders store the absolute paths to the shared library in the target program's memory. If you use `solib-absolute-prefix' to find shared libraries, they need to be laid out in the same way that they are on the target, with e.g. a `/usr/lib' hierarchy under path. You can set the default value of `solib-absolute-prefix' by using the configure-time `--with-sysroot' option.

　　solib-search-path ：

　　If this variable is set, path is a colon-separated list of directories to search for shared libraries. `solib-search-path' is used after `solib-absolute-prefix' fails to locate the library, or if the path to the library is relative instead of absolute. If you want to use `solib-search-path' instead of `solib-absolute-prefix', be sure to set `solib-absolute-prefix' to a nonexistant directory to prevent GDB from finding your host's libraries.