Not able to hit the break point in ndk-gdb in Android

Question

Development Environment:
NDK: r7
SDK & Tools: r15
AVD: GB2.3.3, API Level 10

I wrote a test application in which thread will be launched in the native. I Kept a break point in the thread. (Intially when i tried on Galaxy S2 i was getting an error, "Thread debugging not supported in this Platform". So i created an AVD 2.3.3 Level 10).

After this i was getting an error like this

    #0  0xafd0c51c in epoll_wait () from /Volumes/SecureCode/webos/rta/android/obj/local/armeabi/libc.so
    #1  0xa81216a6 in ?? ()

I googled and found this Solution (Link Here).

I followed the guide lines there

$ adb pull /system/lib lib

$ ndk-gdb
...
(gdb) set solib-search-path lib

But after this also I am not able to hit the break point. I am still getting stuck at this poll_wait() and not moving forward.

D:\EclipseTestWorkspace\CallbackJava>sh
sh-4.1$ ndk-gdb --force --start --verbose
Android NDK installation path: /cygdrive/c/Android/android-ndk
Using default adb command: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb
ADB version found: Android Debug Bridge version 1.0.29
Using final ADB command: '/cygdrive/c/Android/android-sdk-windows/platform-tools/adb'
Using auto-detected project path: .
Found package name: com.callback
ABIs targetted by application: armeabi
Device API Level: 10
Device CPU ABI: armeabi
Compatible device ABI: armeabi
Found debuggable flag: true
Found device gdbserver: /data/data/com.callback/lib/gdbserver
Using gdb setup init: ./libs/armeabi/gdb.setup
Using toolchain prefix: /cygdrive/c/Android/android-ndk/toolchains/arm-linux-androideabi-4.4.3/prebuilt/windows/bin/arm-linux-androideabi-
Using app out directory: ./obj/local/armeabi
Found data directory: '/data/data/com.callback'
Found first launchable activity: .CallbackJavaActivity
Launching activity: com.callback/.CallbackJavaActivity
## COMMAND: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb shell am start -n com.callback/.CallbackJavaActivity
Starting: Intent { cmp=com.callback/.CallbackJavaActivity }
## COMMAND: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb shell sleep 2
Found running PID: 352
Launched gdbserver succesfully.
## COMMAND: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb shell run-as com.callback lib/gdbserver +debug-socket --attach 352
Setup network redirection
## COMMAND: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb forward tcp:5039 localfilesystem:/data/data/com.callback/debug-socket
## COMMAND: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb pull /system/bin/app_process obj/local/armeabi/app_process
Attached; pid = 352
Listening on sockaddr socket debug-socket
19 KB/s (5660 bytes in 0.281s)
Pulled app_process from device/emulator.
## COMMAND: /cygdrive/c/Android/android-sdk-windows/platform-tools/adb pull /system/lib/libc.so obj/local/armeabi/libc.so
80 KB/s (273868 bytes in 3.325s)
Pulled libc.so from device/emulator.
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "--host=i586-mingw32msvc --target=arm-elf-linux".
(no debugging symbols found)
Error while mapping shared library sections:
/system/bin/linker: No such file or directory.
----- So many similar errors -----
Error while mapping shared library sections:
gralloc.default.so: No such file or directory.
(no debugging symbols found)
warning: Unable to find dynamic linker breakpoint function.
GDB will be unable to debug shared library initializers
and track explicitly loaded dynamic code.
warning: shared library handler failed to enable breakpoint
0xafd0c51c in epoll_wait () from D:/EclipseTestWorkspace/CallbackJava/obj/local/armeabi/libc.so
(gdb) set solib-search-path lib
Error while mapping shared library sections:
/system/bin/linker: No such file or directory.
Error while mapping shared library sections:
gralloc.default.so: No such file or directory.
Symbol file not found for /system/bin/linker
Reading symbols from D:\EclipseTestWorkspace\CallbackJava/lib/libc.so...(no debugging symbols found)...done.
Loaded symbols for D:\EclipseTestWorkspace\CallbackJava/lib/libc.so
----- So many similar errors -----
Loaded symbols for D:\EclipseTestWorkspace\CallbackJava/lib/libwebcore.so
Symbol file not found for gralloc.default.so
(gdb) file ./libs/armeabi/libcallbacks.so
A program is being debugged already.
Are you sure you want to change the file? (y or n) y
Reading symbols from D:\EclipseTestWorkspace\CallbackJava/./libs/armeabi/libcallbacks.so...(no debugging symbols found)...done.
(gdb) file ./obj/local/armeabi/libcallbacks.so
A program is being debugged already.
Are you sure you want to change the file? (y or n) y
Reading symbols from D:\EclipseTestWorkspace\CallbackJava/./obj/local/armeabi/libcallbacks.so...done.
(gdb) break callbacks_java.cpp:appcallback_register
Breakpoint 1 at 0x1a64: file D:/EclipseTestWorkspace/CallbackJava/jni/callbacks_java.cpp, line 419.
(gdb) info breakpoints
Num Type           Disp Enb Address    What
1   breakpoint     keep y   0x00001a64 in appcallback_register at D:/EclipseTestWorkspace/CallbackJava/jni/callbacks_java.cpp:419
(gdb) where
#0  0xafd0c51c in epoll_wait () from D:\EclipseTestWorkspace\CallbackJava/lib/libc.so
#1  0xa81211b4 in android::Looper::pollInner () from D:\EclipseTestWorkspace\CallbackJava/lib/libutils.so
#2  0x00000000 in ?? ()
(gdb) where
#0  0xafd0c51c in epoll_wait () from D:\EclipseTestWorkspace\CallbackJava/lib/libc.so
#1  0xa81211b4 in android::Looper::pollInner () from D:\EclipseTestWorkspace\CallbackJava/lib/libutils.so
#2  0x00000000 in ?? ()
(gdb) c
Continuing.
Warning:
Cannot insert breakpoint 1.
Error accessing memory address 0x1a64: Input/output error.

(gdb)

Which i would like to concentrate on main part as

(gdb) file ./libs/armeabi/libcallbacks.so
A program is being debugged already.
Are you sure you want to change the file? (y or n) y
Reading symbols from D:\EclipseTestWorkspace\CallbackJava/./libs/armeabi/libcallbacks.so...(no debugging symbols found)...done.
(gdb) file ./obj/local/armeabi/libcallbacks.so
A program is being debugged already.
Are you sure you want to change the file? (y or n) y
Reading symbols from D:\EclipseTestWorkspace\CallbackJava/./obj/local/armeabi/libcallbacks.so...done.
(gdb) break callbacks_java.cpp:appcallback_register
Breakpoint 1 at 0x1a64: file D:/EclipseTestWorkspace/CallbackJava/jni/callbacks_java.cpp, line 419.
(gdb) info breakpoints
Num Type           Disp Enb Address    What
1   breakpoint     keep y   0x00001a64 in appcallback_register at D:/EclipseTestWorkspace/CallbackJava/jni/callbacks_java.cpp:419
(gdb) where
#0  0xafd0c51c in epoll_wait () from D:\EclipseTestWorkspace\CallbackJava/lib/libc.so
#1  0xa81211b4 in android::Looper::pollInner () from D:\EclipseTestWorkspace\CallbackJava/lib/libutils.so
#2  0x00000000 in ?? ()
(gdb) where
#0  0xafd0c51c in epoll_wait () from D:\EclipseTestWorkspace\CallbackJava/lib/libc.so
#1  0xa81211b4 in android::Looper::pollInner () from D:\EclipseTestWorkspace\CallbackJava/lib/libutils.so
#2  0x00000000 in ?? ()
(gdb) c
Continuing.
Warning:
Cannot insert breakpoint 1.
Error accessing memory address 0x1a64: Input/output error.

(gdb)

So from the last error what i understand is its considering the absolute address 0x1a64. Its not considering the relative address (runtime address), so not able to hit the break point. and also its getting stuck at the epoll_wait () , not moving further.

Will any one please help me how can I proceed further?

Thanks & Regards,
SSuman185

Answer 1

You could try debugging in Eclipse with DS-5 CE plugin. Tutorial how to install and setup it you can find here http://forums.arm.com/index.php?/topic/15575-arm-ds-5-tutorial-for-android/ (last post is how to make it work on SGS2).

I know that is not an exact answer to your question, but if you need NDK debugging on SGS2 you might want to try it, also it's for Eclipse, not a command line gdb (but who could ever prefer command-line debugging instead of debugging in IDE??)

PS. DS-5 CE is a first NDK debugging tool that worked for me with SGS2 (it's not perfect - possibly because of bugs/limitations in SGS2 - but at least works).