summaryrefslogtreecommitdiffstats
path: root/build/android/adb_gdb
blob: f0e5ccda1eb983d1651afe11f181a6464a43b1cc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
#!/bin/bash
#
# Copyright (c) 2012 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
#

# A generic script used to attach to a running Chromium process and
# debug it. Most users should not use this directly, but one of the
# wrapper scripts like adb_gdb_content_shell
#
# Use --help to print full usage instructions.
#

PROGNAME=$(basename "$0")
PROGDIR=$(dirname "$0")

# Force locale to C to allow recognizing output from subprocesses.
LC_ALL=C

# Location of Chromium-top-level sources.
CHROMIUM_SRC=$(cd "$PROGDIR"/../.. >/dev/null && pwd 2>/dev/null)

TMPDIR=
GDBSERVER_PIDFILE=
TARGET_GDBSERVER=
COMMAND_PREFIX=

clean_exit () {
  if [ "$TMPDIR" ]; then
    GDBSERVER_PID=$(cat $GDBSERVER_PIDFILE 2>/dev/null)
    if [ "$GDBSERVER_PID" ]; then
      log "Killing background gdbserver process: $GDBSERVER_PID"
      kill -9 $GDBSERVER_PID >/dev/null 2>&1
    fi
    if [ "$TARGET_GDBSERVER" ]; then
      log "Removing target gdbserver binary: $TARGET_GDBSERVER."
      "$ADB" shell "$COMMAND_PREFIX" rm "$TARGET_GDBSERVER" >/dev/null 2>&1
    fi
    log "Cleaning up: $TMPDIR"
    rm -rf "$TMPDIR"
  fi
  trap "" EXIT
  exit $1
}

# Ensure clean exit on Ctrl-C or normal exit.
trap "clean_exit 1" INT HUP QUIT TERM
trap "clean_exit \$?" EXIT

panic () {
  echo "ERROR: $@" >&2
  exit 1
}

fail_panic () {
  if [ $? != 0 ]; then panic "$@"; fi
}

log () {
  if [ "$VERBOSE" -gt 0 ]; then
    echo "$@"
  fi
}

DEFAULT_PULL_LIBS_DIR=/tmp/$USER-adb-gdb-libs

# NOTE: Allow wrapper scripts to set various default through ADB_GDB_XXX
# environment variables. This is only for cosmetic reasons, i.e. to
# display proper

# Allow wrapper scripts to set the default activity through
# the ADB_GDB_ACTIVITY variable. Users are still able to change the
# final activity name through --activity=<name> option.
#
# This is only for cosmetic reasons, i.e. to display the proper default
# in the --help output.
#
DEFAULT_ACTIVITY=${ADB_GDB_ACTIVITY:-".Main"}

# Allow wrapper scripts to set the program name through ADB_GDB_PROGNAME
PROGNAME=${ADB_GDB_PROGNAME:-$(basename "$0")}

ACTIVITY=$DEFAULT_ACTIVITY
ADB=
ANNOTATE=
FORCE=
GDBEXEPOSTFIX=gdb
GDBINIT=
GDBSERVER=
HELP=
NDK_DIR=
NO_PULL_LIBS=
PACKAGE_NAME=
PID=
PORT=
PRIVILEGED=
PRIVILEGED_INDEX=
PROGRAM_NAME="activity"
PULL_LIBS=
PULL_LIBS_DIR=
SANDBOXED=
SANDBOXED_INDEX=
START=
ATTACH_DELAY=1
SU_PREFIX=
SYMBOL_DIR=
TARGET_ARCH=
TOOLCHAIN=
VERBOSE=0

for opt; do
  optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
  case $opt in
    --adb=*)
      ADB=$optarg
      ;;
    --device=*)
      export ANDROID_SERIAL=$optarg
      ;;
    --activity=*)
      ACTIVITY=$optarg
      ;;
    --annotate=3)
      ANNOTATE=$optarg
      ;;
    --force)
      FORCE=true
      ;;
    --gdbserver=*)
      GDBSERVER=$optarg
      ;;
    --gdb=*)
      GDB=$optarg
      ;;
    --help|-h|-?)
      HELP=true
      ;;
    --ndk-dir=*)
      NDK_DIR=$optarg
      ;;
    --no-pull-libs)
      NO_PULL_LIBS=true
      ;;
    --package-name=*)
      PACKAGE_NAME=$optarg
      ;;
    --pid=*)
      PID=$optarg
      ;;
    --port=*)
      PORT=$optarg
      ;;
    --privileged)
      PRIVILEGED=true
      ;;
    --privileged=*)
      PRIVILEGED=true
      PRIVILEGED_INDEX=$optarg
      ;;
    --program-name=*)
      PROGRAM_NAME=$optarg
      ;;
    --pull-libs)
      PULL_LIBS=true
      ;;
    --pull-libs-dir=*)
      PULL_LIBS_DIR=$optarg
      ;;
    --sandboxed)
      SANDBOXED=true
      ;;
    --sandboxed=*)
      SANDBOXED=true
      SANDBOXED_INDEX=$optarg
      ;;
    --script=*)
      GDBINIT=$optarg
      ;;
    --start)
      START=true
      ;;
    --attach-delay=*)
      ATTACH_DELAY=$optarg
      ;;
    --su-prefix=*)
      SU_PREFIX=$optarg
      ;;
    --symbol-dir=*)
      SYMBOL_DIR=$optarg
      ;;
    --output-directory=*)
      CHROMIUM_OUTPUT_DIR=$optarg
      ;;
    --target-arch=*)
      TARGET_ARCH=$optarg
      ;;
    --toolchain=*)
      TOOLCHAIN=$optarg
      ;;
    --ui)
      GDBEXEPOSTFIX=gdbtui
      ;;
    --verbose)
      VERBOSE=$(( $VERBOSE + 1 ))
      ;;
    -*)
      panic "Unknown option $opt, see --help." >&2
      ;;
    *)
      if [ "$PACKAGE_NAME" ]; then
        panic "You can only provide a single package name as argument!\
 See --help."
      fi
      PACKAGE_NAME=$opt
      ;;
  esac
done

if [ "$HELP" ]; then
  if [ "$ADB_GDB_PROGNAME" ]; then
    # Assume wrapper scripts all provide a default package name.
    cat <<EOF
Usage: $PROGNAME [options]

Attach gdb to a running Android $PROGRAM_NAME process.
EOF
  else
    # Assume this is a direct call to adb_gdb
  cat <<EOF
Usage: $PROGNAME [options] [<package-name>]

Attach gdb to a running Android $PROGRAM_NAME process.

If provided, <package-name> must be the name of the Android application's
package name to be debugged. You can also use --package-name=<name> to
specify it.
EOF
  fi

  cat <<EOF

This script is used to debug a running $PROGRAM_NAME process.
This can be a regular Android application process, sandboxed (if you use the
--sandboxed or --sandboxed=<num> option) or a privileged (--privileged or
--privileged=<num>) service.

This script needs several things to work properly. It will try to pick
them up automatically for you though:

   - target gdbserver binary
   - host gdb client (e.g. arm-linux-androideabi-gdb)
   - directory with symbolic version of $PROGRAM_NAME's shared libraries.

You can also use --ndk-dir=<path> to specify an alternative NDK installation
directory.

The script tries to find the most recent version of the debug version of
shared libraries under one of the following directories:

  \$CHROMIUM_SRC/<out>/lib/                (used by GYP builds)
  \$CHROMIUM_SRC/<out>/lib.unstripped/     (used by GN builds)

Where <out> is determined by CHROMIUM_OUTPUT_DIR, or --output-directory.

You can set the path manually via --symbol-dir.

The script tries to extract the target architecture from your target device,
but if this fails, will default to 'arm'. Use --target-arch=<name> to force
its value.

Otherwise, the script will complain, but you can use the --gdbserver,
--gdb and --symbol-lib options to specify everything manually.

An alternative to --gdb=<file> is to use --toollchain=<path> to specify
the path to the host target-specific cross-toolchain.

You will also need the 'adb' tool in your path. Otherwise, use the --adb
option. The script will complain if there is more than one device connected
and a device is not specified with either --device or ANDROID_SERIAL).

The first time you use it on a device, the script will pull many system
libraries required by the process into a temporary directory. This
is done to strongly improve the debugging experience, like allowing
readable thread stacks and more. The libraries are copied to the following
directory by default:

  $DEFAULT_PULL_LIBS_DIR/

But you can use the --pull-libs-dir=<path> option to specify an
alternative. The script can detect when you change the connected device,
and will re-pull the libraries only in this case. You can however force it
with the --pull-libs option.

Any local .gdbinit script will be ignored, but it is possible to pass a
gdb command script with the --script=<file> option. Note that its commands
will be passed to gdb after the remote connection and library symbol
loading have completed.

Valid options:
  --help|-h|-?          Print this message.
  --verbose             Increase verbosity.

  --sandboxed           Debug first sandboxed process we find.
  --sandboxed=<num>     Debug specific sandboxed process.
  --symbol-dir=<path>   Specify directory with symbol shared libraries.
  --output-directory=<path> Specify the output directory (e.g. "out/Debug").
  --package-name=<name> Specify package name (alternative to 1st argument).
  --privileged          Debug first privileged process we find.
  --privileged=<num>    Debug specific privileged process.
  --program-name=<name> Specify program name (cosmetic only).
  --pid=<pid>           Specify application process pid.
  --force               Kill any previous debugging session, if any.
  --start               Start package's activity on device.
  --attach-delay=<num>  Seconds to wait for gdbserver to attach to the
                        remote process before starting gdb. Default 1.
                        <num> may be a float if your sleep(1) supports it.
  --ui                  Use gdbtui instead of gdb
  --activity=<name>     Activity name for --start [$DEFAULT_ACTIVITY].
  --annotate=<num>      Enable gdb annotation.
  --script=<file>       Specify extra GDB init script.

  --gdbserver=<file>    Specify target gdbserver binary.
  --gdb=<file>          Specify host gdb client binary.
  --target-arch=<name>  Specify NDK target arch.
  --adb=<file>          Specify host ADB binary.
  --device=<file>       ADB device serial to use (-s flag).
  --port=<port>         Specify the tcp port to use.

  --su-prefix=<prefix>  Prepend <prefix> to 'adb shell' commands that are
                        run by this script. This can be useful to use
                        the 'su' program on rooted production devices.
                        e.g. --su-prefix="su -c"

  --pull-libs           Force system libraries extraction.
  --no-pull-libs        Do not extract any system library.
  --libs-dir=<path>     Specify system libraries extraction directory.

EOF
  exit 0
fi

if [ -z "$PACKAGE_NAME" ]; then
  panic "Please specify a package name on the command line. See --help."
fi

if [[ -z "$CHROMIUM_OUTPUT_DIR" ]]; then
  if [[ -e "build.ninja" ]]; then
    CHROMIUM_OUTPUT_DIR=$PWD
  else
    panic "Please specify an output directory by using one of:
       --output-directory=out/Debug
       CHROMIUM_OUTPUT_DIR=out/Debug
       Setting working directory to an output directory.
       See --help."
   fi
fi

if [ -z "$NDK_DIR" ]; then
  ANDROID_NDK_ROOT=$(PYTHONPATH=$CHROMIUM_SRC/build/android python -c \
'from pylib.constants import ANDROID_NDK_ROOT; print ANDROID_NDK_ROOT,')
else
  if [ ! -d "$NDK_DIR" ]; then
    panic "Invalid directory: $NDK_DIR"
  fi
  if [ ! -f "$NDK_DIR/ndk-build" ]; then
    panic "Not a valid NDK directory: $NDK_DIR"
  fi
  ANDROID_NDK_ROOT=$NDK_DIR
fi

if [ "$GDBINIT" -a ! -f "$GDBINIT" ]; then
  panic "Unknown --script file: $GDBINIT"
fi

# Check that ADB is in our path
if [ -z "$ADB" ]; then
  ADB=$(which adb 2>/dev/null)
  if [ -z "$ADB" ]; then
    panic "Can't find 'adb' tool in your path. Install it or use \
--adb=<file>"
  fi
  log "Auto-config: --adb=$ADB"
fi

# Check that it works minimally
ADB_VERSION=$($ADB version 2>/dev/null)
echo "$ADB_VERSION" | fgrep -q -e "Android Debug Bridge"
if [ $? != 0 ]; then
  panic "Your 'adb' tool seems invalid, use --adb=<file> to specify a \
different one: $ADB"
fi

# If there are more than one device connected, and ANDROID_SERIAL is not
# defined, print an error message.
NUM_DEVICES_PLUS2=$($ADB devices 2>/dev/null | wc -l)
if [ "$NUM_DEVICES_PLUS2" -gt 3 -a -z "$ANDROID_SERIAL" ]; then
  echo "ERROR: There is more than one Android device connected to ADB."
  echo "Please define ANDROID_SERIAL to specify which one to use."
  exit 1
fi

# Run a command through adb shell, strip the extra \r from the output
# and return the correct status code to detect failures. This assumes
# that the adb shell command prints a final \n to stdout.
# $1+: command to run
# Out: command's stdout
# Return: command's status
# Note: the command's stderr is lost
adb_shell () {
  local TMPOUT="$(mktemp)"
  local LASTLINE RET
  local ADB=${ADB:-adb}

  # The weird sed rule is to strip the final \r on each output line
  # Since 'adb shell' never returns the command's proper exit/status code,
  # we force it to print it as '%%<status>' in the temporary output file,
  # which we will later strip from it.
  $ADB shell $@ ";" echo "%%\$?" 2>/dev/null | \
      sed -e 's![[:cntrl:]]!!g' > $TMPOUT
  # Get last line in log, which contains the exit code from the command
  LASTLINE=$(sed -e '$!d' $TMPOUT)
  # Extract the status code from the end of the line, which must
  # be '%%<code>'.
  RET=$(echo "$LASTLINE" | \
    awk '{ if (match($0, "%%[0-9]+$")) { print substr($0,RSTART+2); } }')
  # Remove the status code from the last line. Note that this may result
  # in an empty line.
  LASTLINE=$(echo "$LASTLINE" | \
    awk '{ if (match($0, "%%[0-9]+$")) { print substr($0,1,RSTART-1); } }')
  # The output itself: all lines except the status code.
  sed -e '$d' $TMPOUT && printf "%s" "$LASTLINE"
  # Remove temp file.
  rm -f $TMPOUT
  # Exit with the appropriate status.
  return $RET
}

# Find the target architecture from the target device.
# This returns an NDK-compatible architecture name.
# out: NDK Architecture name, or empty string.
get_gyp_target_arch () {
  local ARCH=$(adb_shell getprop ro.product.cpu.abi)
  case $ARCH in
    mips|x86|x86_64) echo "$ARCH";;
    arm64*) echo "arm64";;
    arm*) echo "arm";;
    *) echo "";
  esac
}

if [ -z "$TARGET_ARCH" ]; then
  TARGET_ARCH=$(get_gyp_target_arch)
  if [ -z "$TARGET_ARCH" ]; then
    TARGET_ARCH=arm
  fi
else
  # Nit: accept Chromium's 'ia32' as a valid target architecture. This
  # script prefers the NDK 'x86' name instead because it uses it to find
  # NDK-specific files (host gdb) with it.
  if [ "$TARGET_ARCH" = "ia32" ]; then
    TARGET_ARCH=x86
    log "Auto-config: --arch=$TARGET_ARCH  (equivalent to ia32)"
  fi
fi

# Detect the NDK system name, i.e. the name used to identify the host.
# out: NDK system name (e.g. 'linux' or 'darwin')
get_ndk_host_system () {
  local HOST_OS
  if [ -z "$NDK_HOST_SYSTEM" ]; then
    HOST_OS=$(uname -s)
    case $HOST_OS in
      Linux) NDK_HOST_SYSTEM=linux;;
      Darwin) NDK_HOST_SYSTEM=darwin;;
      *) panic "You can't run this script on this system: $HOST_OS";;
    esac
  fi
  echo "$NDK_HOST_SYSTEM"
}

# Detect the NDK host architecture name.
# out: NDK arch name (e.g. 'x86' or 'x86_64')
get_ndk_host_arch () {
  local HOST_ARCH HOST_OS
  if [ -z "$NDK_HOST_ARCH" ]; then
    HOST_OS=$(get_ndk_host_system)
    HOST_ARCH=$(uname -p)
    case $HOST_ARCH in
      i?86) NDK_HOST_ARCH=x86;;
      x86_64|amd64) NDK_HOST_ARCH=x86_64;;
      *) panic "You can't run this script on this host architecture: $HOST_ARCH";;
    esac
    # Darwin trick: "uname -p" always returns i386 on 64-bit installations.
    if [ "$HOST_OS" = darwin -a "$NDK_HOST_ARCH" = "x86" ]; then
      # Use '/usr/bin/file', not just 'file' to avoid buggy MacPorts
      # implementations of the tool. See http://b.android.com/53769
      HOST_64BITS=$(/usr/bin/file -L "$SHELL" | grep -e "x86[_-]64")
      if [ "$HOST_64BITS" ]; then
        NDK_HOST_ARCH=x86_64
      fi
    fi
  fi
  echo "$NDK_HOST_ARCH"
}

# Convert an NDK architecture name into a GNU configure triplet.
# $1: NDK architecture name (e.g. 'arm')
# Out: Android GNU configure triplet (e.g. 'arm-linux-androideabi')
get_arch_gnu_config () {
  case $1 in
    arm)
      echo "arm-linux-androideabi"
      ;;
    arm64)
      echo "aarch64-linux-android"
      ;;
    x86)
      echo "i686-linux-android"
      ;;
    x86_64)
      echo "x86_64-linux-android"
      ;;
    mips)
      echo "mipsel-linux-android"
      ;;
    *)
      echo "$ARCH-linux-android"
      ;;
  esac
}

# Convert an NDK architecture name into a toolchain name prefix
# $1: NDK architecture name (e.g. 'arm')
# Out: NDK toolchain name prefix (e.g. 'arm-linux-androideabi')
get_arch_toolchain_prefix () {
  # Return the configure triplet, except for x86!
  if [ "$1" = "x86" ]; then
    echo "$1"
  else
    get_arch_gnu_config $1
  fi
}

# Find a NDK toolchain prebuilt file or sub-directory.
# This will probe the various arch-specific toolchain directories
# in the NDK for the needed file.
# $1: NDK install path
# $2: NDK architecture name
# $3: prebuilt sub-path to look for.
# Out: file path, or empty if none is found.
get_ndk_toolchain_prebuilt () {
  local NDK_DIR="${1%/}"
  local ARCH="$2"
  local SUBPATH="$3"
  local NAME="$(get_arch_toolchain_prefix $ARCH)"
  local FILE TARGET
  FILE=$NDK_DIR/toolchains/$NAME-4.9/prebuilt/$SUBPATH
  if [ ! -f "$FILE" ]; then
    FILE=$NDK_DIR/toolchains/$NAME-4.8/prebuilt/$SUBPATH
    if [ ! -f "$FILE" ]; then
      FILE=
    fi
  fi
  echo "$FILE"
}

# Find the path to an NDK's toolchain full prefix for a given architecture
# $1: NDK install path
# $2: NDK target architecture name
# Out: install path + binary prefix (e.g.
#      ".../path/to/bin/arm-linux-androideabi-")
get_ndk_toolchain_fullprefix () {
  local NDK_DIR="$1"
  local ARCH="$2"
  local TARGET NAME HOST_OS HOST_ARCH GCC CONFIG

  # NOTE: This will need to be updated if the NDK changes the names or moves
  #        the location of its prebuilt toolchains.
  #
  GCC=
  HOST_OS=$(get_ndk_host_system)
  HOST_ARCH=$(get_ndk_host_arch)
  CONFIG=$(get_arch_gnu_config $ARCH)
  GCC=$(get_ndk_toolchain_prebuilt \
        "$NDK_DIR" "$ARCH" "$HOST_OS-$HOST_ARCH/bin/$CONFIG-gcc")
  if [ -z "$GCC" -a "$HOST_ARCH" = "x86_64" ]; then
    GCC=$(get_ndk_toolchain_prebuilt \
          "$NDK_DIR" "$ARCH" "$HOST_OS-x86/bin/$CONFIG-gcc")
  fi
  if [ ! -f "$GCC" -a "$ARCH" = "x86" ]; then
    # Special case, the x86 toolchain used to be incorrectly
    # named i686-android-linux-gcc!
    GCC=$(get_ndk_toolchain_prebuilt \
          "$NDK_DIR" "$ARCH" "$HOST_OS-x86/bin/i686-android-linux-gcc")
  fi
  if [ -z "$GCC" ]; then
    panic "Cannot find Android NDK toolchain for '$ARCH' architecture. \
Please verify your NDK installation!"
  fi
  echo "${GCC%%gcc}"
}

# $1: NDK install path
# $2: target architecture.
get_ndk_gdbserver () {
  local NDK_DIR="$1"
  local ARCH=$2
  local BINARY

  # The location has moved after NDK r8
  BINARY=$NDK_DIR/prebuilt/android-$ARCH/gdbserver/gdbserver
  if [ ! -f "$BINARY" ]; then
    BINARY=$(get_ndk_toolchain_prebuilt "$NDK_DIR" "$ARCH" gdbserver)
  fi
  echo "$BINARY"
}

# Check/probe the path to the Android toolchain installation. Always
# use the NDK versions of gdb and gdbserver. They must match to avoid
# issues when both binaries do not speak the same wire protocol.
#
if [ -z "$TOOLCHAIN" ]; then
  ANDROID_TOOLCHAIN=$(get_ndk_toolchain_fullprefix \
                      "$ANDROID_NDK_ROOT" "$TARGET_ARCH")
  ANDROID_TOOLCHAIN=$(dirname "$ANDROID_TOOLCHAIN")
  log "Auto-config: --toolchain=$ANDROID_TOOLCHAIN"
else
  # Be flexible, allow one to specify either the install path or the bin
  # sub-directory in --toolchain:
  #
  if [ -d "$TOOLCHAIN/bin" ]; then
    TOOLCHAIN=$TOOLCHAIN/bin
  fi
  ANDROID_TOOLCHAIN=$TOOLCHAIN
fi

# Cosmetic: Remove trailing directory separator.
ANDROID_TOOLCHAIN=${ANDROID_TOOLCHAIN%/}

# Find host GDB client binary
if [ -z "$GDB" ]; then
  GDB=$(which $ANDROID_TOOLCHAIN/*-$GDBEXEPOSTFIX 2>/dev/null | head -1)
  if [ -z "$GDB" ]; then
    panic "Can't find Android gdb client in your path, check your \
--toolchain or --gdb path."
  fi
  log "Host gdb client: $GDB"
fi

# Find gdbserver binary, we will later push it to /data/local/tmp
# This ensures that both gdbserver and $GDB talk the same binary protocol,
# otherwise weird problems will appear.
#
if [ -z "$GDBSERVER" ]; then
  GDBSERVER=$(get_ndk_gdbserver "$ANDROID_NDK_ROOT" "$TARGET_ARCH")
  if [ -z "$GDBSERVER" ]; then
    panic "Can't find NDK gdbserver binary. use --gdbserver to specify \
valid one!"
  fi
  log "Auto-config: --gdbserver=$GDBSERVER"
fi

# A unique ID for this script's session. This needs to be the same in all
# sub-shell commands we're going to launch, so take the PID of the launcher
# process.
TMP_ID=$$

# Temporary directory, will get cleaned up on exit.
TMPDIR=/tmp/$USER-adb-gdb-tmp-$TMP_ID
mkdir -p "$TMPDIR" && rm -rf "$TMPDIR"/*

GDBSERVER_PIDFILE="$TMPDIR"/gdbserver-$TMP_ID.pid

# If --force is specified, try to kill any gdbserver process started by the
# same user on the device. Normally, these are killed automatically by the
# script on exit, but there are a few corner cases where this would still
# be needed.
if [ "$FORCE" ]; then
  GDBSERVER_PIDS=$(adb_shell ps | awk '$9 ~ /gdbserver/ { print $2; }')
  for GDB_PID in $GDBSERVER_PIDS; do
    log "Killing previous gdbserver (PID=$GDB_PID)"
    adb_shell kill -9 $GDB_PID
  done
fi

if [ "$START" ]; then
  log "Starting $PROGRAM_NAME on device."
  adb_shell am start -n $PACKAGE_NAME/$ACTIVITY 2>/dev/null
  adb_shell ps | grep -q $PACKAGE_NAME
  fail_panic "Could not start $PROGRAM_NAME on device. Are you sure the \
package is installed?"
fi

# Return the timestamp of a given file, as number of seconds since epoch.
# $1: file path
# Out: file timestamp
get_file_timestamp () {
  stat -c %Y "$1" 2>/dev/null
}

# Detect the build type and symbol directory. This is done by finding
# the most recent sub-directory containing debug shared libraries under
# $CHROMIUM_OUTPUT_DIR.
#
# Out: nothing, but this sets SYMBOL_DIR
#
detect_symbol_dir () {
  # GYP places unstripped libraries under out/lib
  # GN places them under out/lib.unstripped
  local PARENT_DIR="$CHROMIUM_OUTPUT_DIR"
  if [[ ! -e "$PARENT_DIR" ]]; then
    PARENT_DIR="$CHROMIUM_SRC/$PARENT_DIR"
  fi
  SYMBOL_DIR="$PARENT_DIR/lib.unstripped"
  if [[ -z "$(ls "$SYMBOL_DIR"/lib*.so 2>/dev/null)" ]]; then
    SYMBOL_DIR="$PARENT_DIR/lib"
    if [[ -z "$(ls "$SYMBOL_DIR"/lib*.so 2>/dev/null)" ]]; then
      panic "Could not find any symbols under \
$PARENT_DIR/lib{.unstripped}. Please build the program first!"
    fi
  fi
  log "Auto-config: --symbol-dir=$SYMBOL_DIR"
}

if [ -z "$SYMBOL_DIR" ]; then
  detect_symbol_dir
fi

# Allow several concurrent debugging sessions
TARGET_GDBSERVER=/data/data/$PACKAGE_NAME/gdbserver-adb-gdb-$TMP_ID
TMP_TARGET_GDBSERVER=/data/local/tmp/gdbserver-adb-gdb-$TMP_ID

# Return the build fingerprint contained in a build.prop file.
# $1: path to build.prop file
get_build_fingerprint_from () {
  cat "$1" | grep -e '^ro.build.fingerprint=' | cut -d= -f2
}


ORG_PULL_LIBS_DIR=$PULL_LIBS_DIR
PULL_LIBS_DIR=${PULL_LIBS_DIR:-$DEFAULT_PULL_LIBS_DIR}

HOST_FINGERPRINT=
DEVICE_FINGERPRINT=$(adb_shell getprop ro.build.fingerprint)
[[ "$DEVICE_FINGERPRINT" ]] || panic "Failed to get the device fingerprint"
log "Device build fingerprint: $DEVICE_FINGERPRINT"

# If --pull-libs-dir is not specified, and this is a platform build, look
# if we can use the symbolic libraries under $ANDROID_PRODUCT_OUT/symbols/
# directly, if the build fingerprint matches the device.
if [ -z "$ORG_PULL_LIBS_DIR" -a \
     "$ANDROID_PRODUCT_OUT" -a \
     -f "$ANDROID_PRODUCT_OUT/system/build.prop" ]; then
  ANDROID_FINGERPRINT=$(get_build_fingerprint_from \
                        "$ANDROID_PRODUCT_OUT"/system/build.prop)
  log "Android build fingerprint:  $ANDROID_FINGERPRINT"
  if [ "$ANDROID_FINGERPRINT" = "$DEVICE_FINGERPRINT" ]; then
    log "Perfect match!"
    PULL_LIBS_DIR=$ANDROID_PRODUCT_OUT/symbols
    HOST_FINGERPRINT=$ANDROID_FINGERPRINT
    if [ "$PULL_LIBS" ]; then
      log "Ignoring --pull-libs since the device and platform build \
fingerprints match."
      NO_PULL_LIBS=true
    fi
  fi
fi

# If neither --pull-libs an --no-pull-libs were specified, check the build
# fingerprints of the device, and the cached system libraries on the host.
#
if [ -z "$NO_PULL_LIBS" -a -z "$PULL_LIBS" ]; then
  if [ ! -f "$PULL_LIBS_DIR/build.fingerprint" ]; then
    log "Auto-config: --pull-libs  (no cached libraries)"
    PULL_LIBS=true
  else
    HOST_FINGERPRINT=$(< "$PULL_LIBS_DIR/build.fingerprint")
    log "Host build fingerprint:   $HOST_FINGERPRINT"
    if [ "$HOST_FINGERPRINT" == "$DEVICE_FINGERPRINT" ]; then
      log "Auto-config: --no-pull-libs (fingerprint match)"
      NO_PULL_LIBS=true
    else
      log "Auto-config: --pull-libs  (fingerprint mismatch)"
      PULL_LIBS=true
    fi
  fi
fi

# Extract the system libraries from the device if necessary.
if [ "$PULL_LIBS" -a -z "$NO_PULL_LIBS" ]; then
  echo "Extracting system libraries into: $PULL_LIBS_DIR"
fi

mkdir -p "$PULL_LIBS_DIR"
fail_panic "Can't create --libs-dir directory: $PULL_LIBS_DIR"

# If requested, work for M-x gdb.  The gdb indirections make it
# difficult to pass --annotate=3 to the gdb binary itself.
GDB_ARGS=
if [ "$ANNOTATE" ]; then
  GDB_ARGS=$GDB_ARGS" --annotate=$ANNOTATE"
fi

# Get the PID from the first argument or else find the PID of the
# browser process.
if [ -z "$PID" ]; then
  PROCESSNAME=$PACKAGE_NAME
  if [ "$SANDBOXED_INDEX" ]; then
    PROCESSNAME=$PROCESSNAME:sandboxed_process$SANDBOXED_INDEX
  elif [ "$SANDBOXED" ]; then
    PROCESSNAME=$PROCESSNAME:sandboxed_process
    PID=$(adb_shell ps | \
          awk '$9 ~ /^'$PROCESSNAME'/ { print $2; }' | head -1)
  elif [ "$PRIVILEGED_INDEX" ]; then
    PROCESSNAME=$PROCESSNAME:privileged_process$PRIVILEGED_INDEX
  elif [ "$PRIVILEGED" ]; then
    PROCESSNAME=$PROCESSNAME:privileged_process
    PID=$(adb_shell ps | \
          awk '$9 ~ /^'$PROCESSNAME'/ { print $2; }' | head -1)
  fi
  if [ -z "$PID" ]; then
    PID=$(adb_shell ps | \
          awk '$9 == "'$PROCESSNAME'" { print $2; }' | head -1)
  fi
  if [ -z "$PID" ]; then
    if [ "$START" ]; then
      panic "Can't find application process PID, did it crash?"
    else
      panic "Can't find application process PID, are you sure it is \
running? Try using --start."
    fi
  fi
  log "Found process PID: $PID"
elif [ "$SANDBOXED" ]; then
  echo "WARNING: --sandboxed option ignored due to use of --pid."
elif [ "$PRIVILEGED" ]; then
  echo "WARNING: --privileged option ignored due to use of --pid."
fi

# Determine if 'adb shell' runs as root or not.
# If so, we can launch gdbserver directly, otherwise, we have to
# use run-as $PACKAGE_NAME ..., which requires the package to be debuggable.
#
if [ "$SU_PREFIX" ]; then
  # Need to check that this works properly.
  SU_PREFIX_TEST_LOG=$TMPDIR/su-prefix.log
  adb_shell $SU_PREFIX \"echo "foo"\" > $SU_PREFIX_TEST_LOG 2>&1
  if [ $? != 0 -o "$(cat $SU_PREFIX_TEST_LOG)" != "foo" ]; then
    echo "ERROR: Cannot use '$SU_PREFIX' as a valid su prefix:"
    echo "$ adb shell $SU_PREFIX \"echo foo\""
    cat $SU_PREFIX_TEST_LOG
    exit 1
  fi
  COMMAND_PREFIX="$SU_PREFIX \""
  COMMAND_SUFFIX="\""
else
  SHELL_UID=$(adb shell cat /proc/self/status | \
              awk '$1 == "Uid:" { print $2; }')
  log "Shell UID: $SHELL_UID"
  if [ "$SHELL_UID" != 0 -o -n "$NO_ROOT" ]; then
    COMMAND_PREFIX="run-as $PACKAGE_NAME"
    COMMAND_SUFFIX=
  else
    COMMAND_PREFIX=
    COMMAND_SUFFIX=
  fi
fi
log "Command prefix: '$COMMAND_PREFIX'"
log "Command suffix: '$COMMAND_SUFFIX'"

# Pull device's system libraries that are mapped by our process.
# Pulling all system libraries is too long, so determine which ones
# we need by looking at /proc/$PID/maps instead
if [ "$PULL_LIBS" -a -z "$NO_PULL_LIBS" ]; then
  echo "Extracting system libraries into: $PULL_LIBS_DIR"
  MAPPINGS=$(adb_shell $COMMAND_PREFIX cat /proc/$PID/maps $COMMAND_SUFFIX)
  if [ $? != 0 ]; then
    echo "ERROR: Could not list process's memory mappings."
    if [ "$SU_PREFIX" ]; then
      panic "Are you sure your --su-prefix is correct?"
    else
      panic "Use --su-prefix if the application is not debuggable."
    fi
  fi
  # Remove the fingerprint file in case pulling one of the libs fails.
  rm -f "$PULL_LIBS_DIR/build.fingerprint"
  SYSTEM_LIBS=$(echo "$MAPPINGS" | \
      awk '$6 ~ /\/system\/.*\.so$/ { print $6; }' | sort -u)
  for SYSLIB in /system/bin/linker $SYSTEM_LIBS; do
    echo "Pulling from device: $SYSLIB"
    DST_FILE=$PULL_LIBS_DIR$SYSLIB
    DST_DIR=$(dirname "$DST_FILE")
    mkdir -p "$DST_DIR" && adb pull $SYSLIB "$DST_FILE" 2>/dev/null
    fail_panic "Could not pull $SYSLIB from device !?"
  done
  echo "Writing the device fingerprint"
  echo "$DEVICE_FINGERPRINT" > "$PULL_LIBS_DIR/build.fingerprint"
fi

# Find all the sub-directories of $PULL_LIBS_DIR, up to depth 4
# so we can add them to solib-search-path later.
SOLIB_DIRS=$(find $PULL_LIBS_DIR -mindepth 1 -maxdepth 4 -type d | \
             grep -v "^$" | tr '\n' ':')

# This is a re-implementation of gdbclient, where we use compatible
# versions of gdbserver and $GDBNAME to ensure that everything works
# properly.
#

# Push gdbserver to the device
log "Pushing gdbserver $GDBSERVER to $TARGET_GDBSERVER"
adb push $GDBSERVER $TMP_TARGET_GDBSERVER &>/dev/null
adb shell $COMMAND_PREFIX cp $TMP_TARGET_GDBSERVER $TARGET_GDBSERVER
adb shell rm $TMP_TARGET_GDBSERVER
fail_panic "Could not copy gdbserver to the device!"

if [ -z "$PORT" ]; then
    PORT=5039
fi
HOST_PORT=$PORT
TARGET_PORT=$PORT

# Select correct app_process for architecture.
case $TARGET_ARCH in
      arm|x86|mips) GDBEXEC=app_process32;;
      arm64|x86_64) GDBEXEC=app_process64;;
      *) fail_panic "Unknown app_process for architecture!";;
esac

# Default to app_process if bit-width specific process isn't found.
adb_shell ls /system/bin/$GDBEXEC
if [ $? != 0 ]; then
    GDBEXEC=app_process
fi

# Detect AddressSanitizer setup on the device. In that case app_process is a
# script, and the real executable is app_process.real.
GDBEXEC_ASAN=app_process.real
adb_shell ls /system/bin/$GDBEXEC_ASAN
if [ $? == 0 ]; then
    GDBEXEC=$GDBEXEC_ASAN
fi

# Pull the app_process binary from the device.
log "Pulling $GDBEXEC from device"
adb pull /system/bin/$GDBEXEC "$TMPDIR"/$GDBEXEC &>/dev/null
fail_panic "Could not retrieve $GDBEXEC from the device!"

# Setup network redirection
log "Setting network redirection (host:$HOST_PORT -> device:$TARGET_PORT)"
adb forward tcp:$HOST_PORT tcp:$TARGET_PORT
fail_panic "Could not setup network redirection from \
host:localhost:$HOST_PORT to device:localhost:$TARGET_PORT!"

# Start gdbserver in the background
# Note that using run-as requires the package to be debuggable.
#
# If not, this will fail horribly. The alternative is to run the
# program as root, which requires of course root privileges.
# Maybe we should add a --root option to enable this?
#
log "Starting gdbserver in the background:"
GDBSERVER_LOG=$TMPDIR/gdbserver-$TMP_ID.log
log "adb shell $COMMAND_PREFIX $TARGET_GDBSERVER :$TARGET_PORT \
  --attach $PID $COMMAND_SUFFIX"
"$ADB" shell $COMMAND_PREFIX $TARGET_GDBSERVER :$TARGET_PORT \
  --attach $PID $COMMAND_SUFFIX > $GDBSERVER_LOG 2>&1 &
GDBSERVER_PID=$!
echo "$GDBSERVER_PID" > $GDBSERVER_PIDFILE
log "background job pid: $GDBSERVER_PID"

# Sleep to allow gdbserver to attach to the remote process and be
# ready to connect to.
log "Sleeping ${ATTACH_DELAY}s to allow gdbserver to attach."
sleep "$ATTACH_DELAY"
log "Job control: $(jobs -l)"
STATE=$(jobs -l | awk '$2 == "'$GDBSERVER_PID'" { print $3; }')
if [ "$STATE" != "Running" ]; then
  echo "ERROR: GDBServer either failed to run or attach to PID $PID!"
  if [ $(adb_shell su -c getenforce) != "Permissive" ];  then
    echo "Device mode is Enforcing. Changing Device mode to Permissive "
    $(adb_shell su -c setenforce 0)
    if [ $(adb_shell su -c getenforce) != "Permissive" ]; then
      echo "ERROR: Failed to Change Device mode to Permissive"
      echo "Failure log (use --verbose for more information):"
      cat $GDBSERVER_LOG
      exit 1
    fi
  else
    echo "Failure log (use --verbose for more information):"
    cat $GDBSERVER_LOG
    exit 1
  fi
fi

# Generate a file containing useful GDB initialization commands
readonly COMMANDS=$TMPDIR/gdb.init
log "Generating GDB initialization commands file: $COMMANDS"
echo -n "" > $COMMANDS
echo "set print pretty 1" >> $COMMANDS
echo "python" >> $COMMANDS
echo "import sys" >> $COMMANDS
echo "sys.path.insert(0, '$CHROMIUM_SRC/tools/gdb/')" >> $COMMANDS
echo "try:" >> $COMMANDS
echo "  import gdb_chrome" >> $COMMANDS
echo "finally:" >> $COMMANDS
echo "  sys.path.pop(0)" >> $COMMANDS
echo "end" >> $COMMANDS
echo "file $TMPDIR/$GDBEXEC" >> $COMMANDS
echo "directory $CHROMIUM_SRC" >> $COMMANDS
echo "set solib-absolute-prefix $PULL_LIBS_DIR" >> $COMMANDS
echo "set solib-search-path $SOLIB_DIRS:$PULL_LIBS_DIR:$SYMBOL_DIR" \
    >> $COMMANDS
echo "echo Attaching and reading symbols, this may take a while.." \
    >> $COMMANDS
echo "target remote :$HOST_PORT" >> $COMMANDS

if [ "$GDBINIT" ]; then
  cat "$GDBINIT" >> $COMMANDS
fi

if [ "$VERBOSE" -gt 0 ]; then
  echo "### START $COMMANDS"
  cat $COMMANDS
  echo "### END $COMMANDS"
fi

log "Launching gdb client: $GDB $GDB_ARGS -x $COMMANDS"
$GDB $GDB_ARGS -x $COMMANDS &&
rm -f "$GDBSERVER_PIDFILE"