eosio-blocklog --trim-blocklog --first always fails

[matthewdarwin]

I tried multiple chains and multiple values for "first" and every time it fails to prune the start off the blocks log. Even got a segfault.

Seems like removing early blocks is really not supported.

Note: starting by copying blocks from a live running system.

rm -r /tmp/b/*; cp /var/lib/nodeos/blocks/blocks.index /var/lib/nodeos/blocks/blocks.log /tmp/b/; eosio-blocklog --trim-blocklog --first 2  --blocks-dir=/tmp/b
info  2020-04-15T13:09:51.451 eosio-blo block_log.cpp:963             trim_blocklog_front  ] In directory /tmp/b will trim all blocks before block 2 from blocks.log and blocks.index.
info  2020-04-15T13:09:51.451 eosio-blo block_log.cpp:1081            trim_data            ] block log version= 3
info  2020-04-15T13:09:51.451 eosio-blo block_log.cpp:1133            trim_data            ] first block= 1
info  2020-04-15T13:09:51.451 eosio-blo block_log.cpp:1134            trim_data            ] last block= 4424933
info  2020-04-15T13:09:51.508 eosio-blo block_log.cpp:888             write                ] block: 4194304      position in file: 806012308
info  2020-04-15T13:09:51.743 eosio-blo block_log.cpp:888             write                ] block: 3145728      position in file: 604684439
[1]    24492 segmentation fault  eosio-blocklog --trim-blocklog --first 2 --blocks-dir=/tmp/b

rm -r /tmp/b/*; cp /var/lib/nodeos/blocks/blocks.index /var/lib/nodeos/blocks/blocks.log /tmp/b/; eosio-blocklog --trim-blocklog --first 1000 --blocks-dir=/tmp/b
info  2020-04-15T13:08:44.752 eosio-blo block_log.cpp:963             trim_blocklog_front  ] In directory /tmp/b will trim all blocks before block 1000 from blocks.log and blocks.index.
info  2020-04-15T13:08:44.752 eosio-blo block_log.cpp:1081            trim_data            ] block log version= 3
info  2020-04-15T13:08:44.753 eosio-blo block_log.cpp:1133            trim_data            ] first block= 1
info  2020-04-15T13:08:44.753 eosio-blo block_log.cpp:1134            trim_data            ] last block= 4424801
info  2020-04-15T13:08:44.811 eosio-blo block_log.cpp:888             write                ] block: 4194304      position in file: 805874442
info  2020-04-15T13:08:45.087 eosio-blo block_log.cpp:888             write                ] block: 3145728      position in file: 604546573
error 2020-04-15T13:08:45.791 eosio-blo main.cpp:324                  main                 ] 3190000 block_log_exception: Block log exception
Failed to write buffer to '/tmp/b/old/blocks.index'
    {"blocks_index":"/tmp/b/old/blocks.index"}
    eosio-blocklog  block_log.cpp:930 complete