- store_path() previously only worked for cross compilation packages, we
remove this assumption here
- Add CROSS_GCC_LIB variable which points to where gcc libs/headers are
located
- Add gcc libs/headers to our CROSS_*_PATH environment variables
- Check that all directories in CROSS_*_PATH are sane
Flagged by flake8 v3.6.0, as W605, plus a few others identified
incidentally, e.g. 59ffecf66cf4d08c4b431e457b083878d66a3fd6.
Note that r"\n" matches to "\n" under re.match/search.
f3b57f4a1c Unrecommend making config file owned by bitcoin (setpill)
870d4152df Set ProtectHome in systemd service file (setpill)
639a416e37 Chgrp config dir to bitcoin in systemd service (setpill)
aded0528f0 Improve clarity of systemd service file comments (setpill)
Pull request description:
Rationale: ran into a bug with the systemd service file, fixed it locally and figured I might as well contribute my fix.
Also fixed some unrelated confusing phrasing in the comments of the same file, after discussion in IRC.
ACKs for top commit:
sipsorcery:
tACK f3b57f4a1c (nothing changed since previous tACK).
ryanofsky:
utACK f3b57f4a1c. Only change since last review is removing ConfigurationDirectoryMode churn in early commits
Tree-SHA512: 2188345878925b9e8a5c2c3df8dfba443720e2252a164db54a8e1d8007846721497b2d98c56f1d9b60a9a9ed4fdb1156c7b02c699616b220a9b614671617d32a
Rather than making the config dir world-readable, which potentially
leaks RPC credentials, the group of the directory is changed to the one
the service is executed as.
The phrasing seemed to indicate that the options specified in
ExecStart= could not be specified in the config file, necessitating
their inclusion in the service file. However, the options in the
config file simply get overridden by any specified in ExecStart=.
- Clearer and more accurate prose
- Pin `guix pull' to commit rather than branch
- Just use `use-module' instead of `define-module'
- Use `bash-minimal' instead of `bash'
- Remove unneeded `tcsh' from manifest
- Explicitly use `python-3.7'
- Add comments about how {native,cross}-toolchains are produced and
why
1ac454a384 Enable ShellCheck rules (Hennadii Stepanov)
Pull request description:
Enable some simple ShellCheck rules.
Note for reviewers: `bash` and `shellcheck` on macOS are different from ones on Ubuntu.
For local tests the latest `shellcheck` version 0.6.0 should be used (see #15166).
ACKs for top commit:
practicalswift:
utACK 1ac454a384
dongcarl:
utACK 1ac454a
fanquake:
ACK 1ac454a384
Tree-SHA512: 8d0a3a5c09fe1a0c22120178f5e6b80f81f746f8c3356b7701ff301c117acb2edea8fe08f08fb54ed73f94b1617515fb239fa28e7ab4121f74872e6494b6f20e
88fd556a96 Use placeholder instead of key expiration date (Hennadii Stepanov)
Pull request description:
Use a placeholder instead of the actual expiration date, so that the documentation doesn't require updating every time an expiry date changes.
ACKs for top commit:
fanquake:
ACK 88fd556a96
Tree-SHA512: 391707833cc0e701cf560ec82fd91368468c90a95f85e4ce2a211b20d12463c85775142f28a3536b57c5f6950b9e6e0785632f6f071fa2180bc8aab53008603b
0e01e4522e devtools: Fetch and display ACKs at sign-off time in github-merge (Wladimir J. van der Laan)
Pull request description:
- Fetch the ACKs only at sign-off time. This makes sure that any last-minute ACKs are included (fixes#16200)
- Show a list of ACKs that will be included and their author before signing off, and warn if there are none
There's a slight change to the merge commit format—before it was
```
ACKs for commit 88884c:
(list of ACKs, could be empty)
```
now it is
```
ACKs for top commit:
jnewbery:
ACK 5ebc6b0eb
... (list of ACKs cannot be empty)
```
or
```
Top commit has no ACKs.
```
I don't think there's a reason to have the abbreviated commit ID there, after all the full commit id is already in the beginning of the merge commit message, and at least the abbreviated one is in every single ACK message.
ACKs for commit 0e01e4:
fanquake:
ACK 0e01e4522e
Tree-SHA512: 8576de016137d71cfc101747e9bb6779c13e0953cf2babee7afc9972bf2bd46f6912be4982b54fa5abf4d91e98e8fdae6b4ca3eef7d6892b7a5f04a7017b6882
- Fetch the ACKs only at sign-off time. This makes sure that any
last-minute ACKs are included (fixes#16200)
- Show a list of ACKs and their author before signing off, and warn if
there are none
b748bf6f50 Fix spelling errors identified by codespell 1.15.0 (Ben Woosley)
Pull request description:
Note all changes are to comments / documentation.
After this commit, the only remaining output is:
```
$ test/lint/lint-spelling.sh
src/test/base32_tests.cpp:14: fo ==> of, for
src/test/base64_tests.cpp:14: fo ==> of, for
^ Warning: codespell identified likely spelling errors. Any false positives? Add them to the list of ignored words in test/lint/lint-spelling.ignore-words.txt
```
Note:
* I ignore several valid alternative spellings ~, but changed homogenous
to homogeneous as the latter is a more specific term according to the
Google dictionary definitions I found~
* homogenous is present in tinyformat, hence should be addressed upstream
* process' is correct only if there are plural processes
ACKs for commit b748bf:
practicalswift:
ACK b748bf6f50
fanquake:
ACK b748bf6f50
Tree-SHA512: 9add7044643ce015e0a44d8b27a3f300d72c485ffff550fb6491a17f14528085289ec5caddfe02f291ea9b2cded38a0dd3079652a054e2d7fe2ff4f7b53db5d7
067fba563 devtools: Always use unabbreviated commit IDs in github-merge.py (Wladimir J. van der Laan)
Pull request description:
Always put the unabbreviated commit IDs in the generated commit messages and other places. This prevents the developer's `core.abbrev` git setting from leaking through and is better against ambiguity too.
ACKs for commit 067fba:
MarcoFalke:
ACK 067fba5631 (replaces `h` with `H`, didn't test)
promag:
ACK 067fba5631, from the documentation https://git-scm.com/docs/pretty-formats:
fanquake:
ACK 067fba5631. Tested by merging this PR into master, then merging a second PR ontop and checking that full commit hashes were being used. Also checked documentation linked to above. Did not check that this works when a different `core.abbrev` is set locally.
Tree-SHA512: a851d10490cd8bcd8bca29094b08a6b9f883cfe1b0767ccda7ca789e4c8eff6260a4d82c33cb3d9bab01dd30ac8c9100cb7adbcb1911bb399d9385c1e1f15ecd
Always put the unabbreviated commit IDs in the generated commit messages
and other places. This prevents the developer's `core.abbrev` git setting
from leaking through and is better against ambiguity too.
993aa414d3 scripted-diff: gitian: Use REFERENCE_DATETIME directly. (Carl Dong)
Pull request description:
Fixes regression introduced by #16141.
```
-BEGIN VERIFY SCRIPT-
sed -i 's#\$REFERENCE_DATE\\\\\\ \$REFERENCE_TIME#\$REFERENCE_DATETIME#g' contrib/gitian-descriptors/*
-END VERIFY SCRIPT-
```
-----
Note that this could have been fixed by escaping properly, but using `REFERENCE_DATETIME` directly is simpler.
Future note: `REFERENCE_{DATE{,DATETIME},TIME}` is a bit ridiculous. At the very _least_ gitian should use epoch, as it is the most parse-able, and preferably set SOURCE_DATE_EPOCH.
ACKs for commit 993aa4:
Tree-SHA512: 8457e5fffde66e1d2b846547b6807416b884c171f63569f76dfefd498d2a58ad6f9eb93931eb6cfc7ff38c6b460b0c488ca87d1a68bc630c48f365a74b6ee163
After this commit, the only remaining output is:
$ test/lint/lint-spelling.sh
src/test/base32_tests.cpp:14: fo ==> of, for
src/test/base64_tests.cpp:14: fo ==> of, for
^ Warning: codespell identified likely spelling errors. Any false positives? Add them to the list of ignored words in test/lint/lint-spelling.ignore-words.txt
Note:
* I ignore several valid alternative spellings
* homogenous is present in tinyformat, hence should be addressed upstream
* process' is correct only if there are plural processes
c061be1e2f tests: Mark unit test blockfilter_index_initial_sync as non-deterministic (practicalswift)
Pull request description:
Mark unit test `blockfilter_index_tests/blockfilter_index_initial_sync` as non-deterministic.
Before this PR:
```
$ contrib/devtools/test_deterministic_coverage.sh 500
[2019-06-04 09:58:57] Measuring coverage, run #1 of 500
[2019-06-04 10:00:33] Measuring coverage, run #2 of 500
[2019-06-04 10:02:19] Measuring coverage, run #3 of 500
The line coverage is non-deterministic between runs. Exiting.
The test suite must be deterministic in the sense that the set of lines executed at least
once must be identical between runs. This is a necessary condition for meaningful
coverage measuring.
--- gcovr.run-1.txt 2019-06-04 10:00:33.389059973 +0000
+++ gcovr.run-3.txt 2019-06-04 10:03:45.619491207 +0000
@@ -72,7 +72,7 @@
hash.h 54 33 61% 71,74-77,82,85-89,111,113,128,147-148,175,178-181
httprpc.cpp 120 3 2% 31,34-35,38-40,46,49,52,54,56,58,70,73-74,76,78-79,81,83-84,89,91,94-95,97,99-101,103,106-107,111-112,117-119,121-122,125,128,130,132,134-136,138-139,142,145,148,151-153,156-160,163-166,171,173-175,180-182,185,187,189-190,192,195,198-199,201,203-204,212,215,217,219-222,224,227-228,230,232,237,239-240,243-245,247-251,254,256,259,261-264,266-267 [* 205-206,208-209]
httpserver.cpp 312 6 1% 46,49-50,53,55,80-81,90,92-93,96-98,101,104,106-109,111-112,114,118,120-122,126,128-129,153,155,157-158,164,166-178,180,182,184-188,192,194-196,198-199,201-202,204-205,207-208,213,216-221,225,228-232,236-239,243-244,247-254,256-258,264-267,270-271,274,279,281-282,286,288-290,292-293,297,299-300,303-307,309-310,312-317,322-328,330,332,335,339,341-342,346,352-353,355,358,360,364,368-369,375,378,381-384,388-391,393-394,398-400,402,404-406,409,411-412,414,416,426,428-431,433-434,438,440-441,443,445-446,449,451-455,457-459,463-464,466-469,471-473,475-477,479,482,484,487,490-493,496-497,499-500,502,504,506,508-509,511,513-514,517,519,521-522,527,529-533,535,538,540-543,550-555,558,560-562,570,572-574,577-582,585-590,594-597,600,602-604,606-609,611,614,616,619,621,625-626,628-629,631-632,634-635,640,642-643,646,648-651,653,655-656
-index/base.cpp 149 94 63% 20,22-25,28,66,98,102-103,117-118,140-141,145-146,155,163,175,177-178,181-182,184-185,200-201,203,212,214-215,219-221,228-229,234,236,240,243-244,247-249,258-260,262,270,292-294,308-309 [* 263]
+index/base.cpp 149 97 65% 20,22-25,28,66,98,102-103,117-118,140-141,145-146,155,163,175,177-178,181-182,184-185,200-201,203,212,214-215,219-221,228-229,234,236,240,243-244,247-249,258-260,262,270,308-309 [* 263]
index/base.h 3 2 66% 77
index/blockfilterindex.cpp 199 134 67% 70,79,81,84-88,91,122,139,142,179-181,184-185,188-189,193-194,201-202,207,233,258,262-263,265-266,268,271-272,274,277,279,284,286,288-289,294,301-302,304,322,329,332-333,350,371,373,438,440-441,444,446,449,455-456,459,461,464,466 [* 162-163]
index/blockfilterindex.h 4 4 100%
@@ -358,7 +358,7 @@
util/validation.cpp 5 1 20% 12,15-17
validation.cpp 2167 808 37% 291,293,297-300,302,330,332,340,348,355-357,359,362,364-365,368,371,380,382-383,385-386,388-389,396,398-402,406-413,415,417,419,422-425,439-440,442-443,446,449,455-458,461-464,467,469-470,472,474,476,492,494-495,502-503,505-507,511-513,515,517,523,526,528,533,535,540,542-544,550,552-556,558-560,564,574,578-583,586,590-591,594-596,601-602,607-608,611-612,616-617,619-621,635-636,638,640,647-648,651,657-658,660-662,665-667,673,675,677-678,682-683,690,693,700-701,703-705,709-710,713-714,716,719-720,724-727,733-735,737-739,741-743,747-748,751-752,754,757-764,771,773-774,776-779,785-788,793-794,796-800,815-816,818-822,825,827,830,835,838-839,841-843,846-848,850,853,859,864-867,875,877-879,884-885,887-891,895,899-900,904-906,908-909,911,930-931,933,936,942,944-950,952,959,962,965-968,972,978,982-984,990-991,994-996,999,1003-1004,1011,1013,1015-1019,1022-1023,1026-1032,1056,1065,1079,1091,1108,1112,1114-1118,1125,1127-1130,1133-1135,1138-1139,1147,1149,1151-1152,1155,1197,1199-1201,1206-1209,1211-1212,1226,1230,1232-1234,1236,1238-1241,1245-1246,1256,1258,1260-1262,1264-1266,1268,1278-1280,1282-1283,1286,1289,1291-1292,1294-1302,1305-1311,1319-1323,1330,1332-1333,1336-1339,1379,1383-1384,1395,1401,1405-1407,1411-1414,1423-1428,1438-1440,1451,1455,1458,1471,1480,1497,1503,1519,1525,1527-1530,1532-1533,1536,1538-1539,1549,1551,1553,1555,1559-1562,1571,1573,1578,1580,1582-1584,1588-1589,1594-1597,1601-1606,1613-1616,1619-1623,1630,1632,1635,1637,1639-1640,1642-1646,1658,1660,1675,1688,1711,1713-1715,1742,1755,1760,1765,1769,1811,1815,1817,1841-1845,1855,1942,1946-1947,1956,1984-1986,1991-1992,1994,1996-1999,2005-2007,2010-2012,2022-2023,2028-2031,2038-2039,2042,2044,2049,2058-2061,2064,2114-2115,2117-2118,2120-2124,2152-2153,2156,2159-2163,2165-2169,2171-2172,2176-2178,2187-2188,2191-2194,2199,2207-2211,2215-2220,2224,2227-2230,2235,2237-2238,2261-2263,2265,2274,2278,2286,2301,2303-2304,2306-2309,2311,2313-2318,2320,2322,2325,2327-2328,2330,2332-2334,2338,2340,2343-2344,2407-2410,2430,2445-2447,2507-2509,2511-2514,2518,2520-2521,2523-2524,2561,2564,2590,2592-2593,2595-2598,2603,2620,2626,2658,2719,2724,2773,2776-2777,2779,2781,2783,2785-2788,2791,2793-2795,2799,2801-2802,2805,2807-2809,2813,2816,2818-2821,2825-2826,2832-2834,2841-2845,2848,2854,2858-2859,2861,2865-2868,2872-2875,2880,2884-2885,2890-2891,2894-2895,2897,2900-2906,2908,2910,2912,2918-2922,2924,2928-2929,2940,3002-3005,3009-3010,3026-3028,3036-3037,3039-3040,3045,3053,3056,3077,3080,3090,3112,3118,3129,3133,3135-3136,3141-3142,3150,3190-3193,3259,3268,3273,3277,3282-3285,3303,3314,3321-3324,3338-3341,3345-3346,3348-3350,3360,3372,3392,3397,3403,3406,3408,3435-3441,3443,3468-3469,3485,3487-3488,3492-3493,3534-3536,3542,3547-3549,3552,3565-3566,3601-3602,3610,3628,3630,3632,3645,3647,3649-3651,3653,3657,3659,3661-3669,3675-3680,3686-3687,3691,3693-3697,3702,3704,3706-3708,3711-3718,3720,3724,3726-3729,3748,3750-3752,3754,3758-3759,3763,3765,3767,3772,3774,3777-3778,3780-3781,3783,3787-3788,3790,3792-3794,3798-3800,3823,3825,3828,3830,3832,3836-3838,3841-3843,3845,3848,3850,3854-3856,3858-3859,3861-3862,3864-3867,3870-3873,3875-3876,3879,3882-3883,3886-3893,3899,3901,3905-3909,3911-3915,3922-3924,3926-3928,3931,3933-3934,3940-3942,3945-3947,3952,3954-3955,3957,3960-3961,3964,3966,3968-3972,3975,3977,3980,3982,3985,3987-3988,3992-3996,3998-4006,4008-4009,4011-4012,4014,4016,4019,4021-4022,4024-4026,4028-4032,4037-4041,4043-4045,4047,4050,4053-4054,4057,4060-4064,4066-4067,4069-4075,4079-4080,4086,4089-4091,4094-4097,4101,4106,4108,4110,4112-4114,4116-4117,4119,4121,4123-4124,4126,4128-4130,4132-4134,4138-4142,4144-4147,4154,4158-4163,4166-4169,4172-4173,4177,4179-4180,4183,4185,4187-4189,4191-4193,4195,4197-4201,4207-4208,4212,4220-4223,4230,4232-4233,4237,4240,4243,4247,4249,4251,4253-4255,4265-4266,4277,4279,4282,4285-4287,4292-4293,4296,4298,4302,4305-4306,4310-4311,4315-4318,4360,4363-4367,4370,4377,4397,4412,4415-4416,4418,4421-4422,4424,4426-4429,4433-4437,4439-4441,4448-4452,4454-4456,4458,4460,4462-4467,4471-4475,4477,4480-4481,4486-4488,4493,4496-4503,4505,4507-4511,4513-4514,4517-4519,4529-4531,4546,4600,4638-4639,4647,4653,4662-4664,4696,4703-4704,4718,4720,4723,4725,4727,4730,4732-4733,4736,4738-4739,4742,4744-4745,4750,4752-4757,4761-4765,4769-4770,4774-4776,4779-4781,4783-4785,4787-4790,4793-4794,4800-4801,4803,4807,4809-4810,4812-4813,4815-4816,4823,4827,4829,4831-4832,4834-4835,4838-4840,4842,4845,4848-4849,4853,4855-4856,4858-4863,4866-4872,4877,4891,4907 [* 1085-1086,1140-1141,1513-1514,2201-2202,2428,3569-3570,4400-4401,4442,4453,4504,4522-4523,4526-4527,4818-4819,4873-4874]
validation.h 19 5 26% 338,350-352,356-363,366,484
-validationinterface.cpp 81 50 61% 78-82,85-86,112-113,116,119-120,123-124,126-128,130,133-136,151-153,163-165,169-171
+validationinterface.cpp 83 60 72% 78-82,85-86,112-113,116,133-136,151-153,163-165,169-171
validationinterface.h 9 4 44% 94,105,112,118,135
versionbits.cpp 92 27 29% 33,35-36,38-39,48-50,52-54,56-57,61-62,67-71,73,75-76,80,82-83,91,98,100,102-103,105,109-110,113-118,121-122,124,127,129-130,134,137,141,149,151,153-155,159,177,179,184,194,196,199,201,204,206 [* 26]
versionbits.h 1 1 100%
@@ -400,5 +400,5 @@
zmq/zmqpublishnotifier.h 5 0 0% 12,31,37,43,49
zmq/zmqrpc.cpp 23 3 13% 16,18,20,23,33-35,37,40-47,51,62,64-65
------------------------------------------------------------------------------
-TOTAL 52472 7784 14%
+TOTAL 52474 7797 14%
------------------------------------------------------------------------------
$
```
After this PR:
```
$ contrib/devtools/test_deterministic_coverage.sh 500
[2019-06-03 14:45:25] Measuring coverage, run #1 of 500
[2019-06-03 14:48:15] Measuring coverage, run #2 of 500
[2019-06-03 14:50:49] Measuring coverage, run #3 of 500
[2019-06-03 14:52:20] Measuring coverage, run #4 of 500
[2019-06-03 14:53:49] Measuring coverage, run #5 of 500
…
[2019-06-04 09:04:58] Measuring coverage, run #496 of 500
[2019-06-04 09:07:42] Measuring coverage, run #497 of 500
[2019-06-04 09:10:32] Measuring coverage, run #498 of 500
[2019-06-04 09:13:26] Measuring coverage, run #499 of 500
[2019-06-04 09:16:32] Measuring coverage, run #500 of 500
Coverage test passed: Deterministic coverage across 500 runs.
$
```
ACKs for commit c061be:
Tree-SHA512: 00cd55b4371290d8587ab667c64249bc31d26cc9dc3dd519677eb91ddb9dbc5333dfbdef5e90c7a0d74eecd24757113e7ec3eda836859ddc033b1de715df81b6
8081927c33 scripts: add key for fanquake to trusted keys list (fanquake)
Pull request description:
Adding my key to the [trusted keys list](https://github.com/bitcoin/bitcoin/blob/master/contrib/verify-commits/trusted-keys) to join the maintainer group. I'll gain merge access and will continue with all triage/repo management work. I'll be focusing primarily on build system development with some guidance from theuni.
Some maintainer related discussion from the Core Dev meetup in Amsterdam is available [here](http://diyhpl.us/wiki/transcripts/bitcoin-core-dev-tech/2019-06-06-maintainers/).
ACKs for commit 808192:
MarcoFalke:
ACK 8081927c33
laanwj:
ACK, this matches the key I have 8081927c33:
meshcollider:
ACK, this matches the key I have from the CoreDev New York 2018 keysigning party 8081927c33
IlyasRidhuan:
ACK. 8081927c33 matches the key I have.
Tree-SHA512: 63c390f5ede316263def2f9a897a1046d4ae58e4ea758f379164c6c5afce4928e2c9463fbcac004742838fd4ac1e48679e7a2a0f9095fd134a900f9064584056
00fade007c contrib: use newer config.guess & config.sub in install_db4.sh (fanquake)
Pull request description:
The `config.guess` and `config.sub` packaged with `db-4.8.30.NC.tar.gz` are fairly old (2009) and fail to identify some system types i.e `ppc64le`. Replace them with more modern versions before configuring `db4`.
Fixes#16064.
ACKs for commit 00fade:
jamesob:
tACK 00fade007c
dongcarl:
utACK 00fade007c
laanwj:
Tested ACK 00fade007c
Tree-SHA512: 54f9f2b0fcf802e6a284214035fcb3833577aa5881beb293921b6036b71d0bcd0872f06d14ddc76a4f8c0eee7ba71461dcc99dc907e7ddb5ae403fc02b245538
0f22a0cf2f Fix gitian-build.py --verify option (Hennadii Stepanov)
4c56a798c0 Set/unset USE_LXC, USE_VBOX, USE_DOCKER explicitly (Hennadii Stepanov)
cbbd98863b Fix Docker related issues for gitian-build.py (Hennadii Stepanov)
Pull request description:
1. The Docker does not depend on `apt-cacher-ng` package. Ref: #14002.
2. Do not try to install the Docker if `docker.service` is detected on the system (e.g., the Docker was installed manually). Fix https://github.com/bitcoin/bitcoin/pull/13623#issuecomment-405684241 by **Sjors**.
3. Prevent the setting of more than one environment variable for the `gitian-builder` (an alternative to #13999). E.g., USE_LXC being set shadows USE_DOCKER; for details see [`gitian-builder/libexec/make-clean-vm`](93a62c7d7d/libexec/make-clean-vm (L7)):
```sh
VMSW=KVM
if [ -n "$USE_LXC" ]; then
VMSW=LXC
elif [ -n "$USE_VBOX" ]; then
VMSW=VBOX
elif [ -n "$USE_DOCKER" ]; then
VMSW=DOCKER
fi
```
4. The [`gitian-builder/bin/gverify`](https://github.com/devrandom/gitian-builder/blob/master/bin/gverify) script returns the exit code 1 if a signature verification ends with 'BAD SIGNATURE' or 'MISMATCH' by design. This PR allows to see the verification results for all signatures without a premature fail of the `gitian-build.py` script. Ref: #14014.
ACKs for commit 0f22a0:
Tree-SHA512: 55f8a5cffa20d0c745f51a687f3199cea015fa616e56a0aee4c25b5ca0985036c61e8cf1922515338d8c6a85f873674ebe7a9a56a5069d65a187e383150f1a83
The gitian-builder/bin/gverify script returns the exit code 1 if a
signature verification ends with 'BAD SIGNATURE' or 'MISMATCH' by
design. This commit allows to see the verification results for all
signatures without a premature fail of the gitian-build.py script.
This prevents the setting of more than one environment variable for the
gitian-builder (e.g., USE_LXC being set shadows USE_DOCKER; for details
see gitian-builder/libexec/make-clean-vm).
The Docker does not depend on apt-cacher-ng package.
Do not try to install the Docker if docker.service is detected on the
system (e.g., the Docker was installed manually).
Also small style corrections were applied.
