When we map a file for generating the DAG, we do a simple truncate to e.g. 1Gb. This is fine, even if we have nowhere near 1Gb disk available, as the actual file doesn't take up the full 1Gb, merely a few bytes. When we start generating into it, however, it eventually crashes with a unexpected fault address .

This change fixes it (on linux systems) by using the Fallocate syscall, which preallocates suffcient space on disk to avoid that situation. 
Co-authored-by: Felix Lange <fjl@twurst.com>

This PR offers two more database sub commands for exporting and importing data.
Two exporters are implemented: preimage and snapshot data respectively. 
The import command is generic, it can take any data export and import into leveldb. 
The data format has a 'magic' for disambiguation, and a version field for future compatibility. 

It is because write known block only checks block and state without snapshot, which could lead to gap between newest snapshot and newest block state. However, new blocks which would cause snapshot to become fixed were ignored, since state was already known. 
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>

Co-authored-by: mrx <mrx@mrx.com>

Don't bother fetching genesis
Co-authored-by: wuff1996 <33193253+wuff1996@users.noreply.github.com>

Some benchmarks in eth/filters were not good: they weren't reproducible, relying on geth chaindata to be present.

Another one was rejected because the receipt was lacking a backing transcation.

The p2p simulation benchmark had a lot of the warnings below, due to the framework calling both
Stop() and Close(). Apparently, the simulated adapter is the only implementation which has a Close(),
and there is no need to call both Stop and Close on it.

This PR adds support for ArrowGlacier, as defined by

    https://github.com/ethereum/execution-specs/blob/master/network-upgrades/mainnet-upgrades/arrow-glacier.md
    https://eips.ethereum.org/EIPS/eip-4345

> Starting with FORK_BLOCK_NUMBER the client will calculate the difficulty based on a fake block number suggesting to the client that the difficulty bomb is adjusting 10,700,000 blocks later than the actual block number.

This also adds support for evm t8n to return the calculated difficulty, so it can be used to construct test.

* cmd/evm: handle rlp errors in t9n

* cmd/evm/testdata: fix readme

Fixes crashes in various benchmarks in the core package

This PR also counts the size of the key when calculating the size of a db batch

* core: write test showing that TD is not stored properly at genesis

The ToBlock method applies a default value for an empty
difficulty value. This default is not carried over through the Commit
method because the TotalDifficulty database write writes the
original difficulty value (nil) instead of the defaulty value
present on the genesis Block.

Date: 2021-10-22 08:25:32-07:00
Signed-off-by: meows <b5c6@protonmail.com>

* core: write TD value from Block, not original genesis value

This an issue where a default TD value was not written to
the database, resulting in a 0 value TD at genesis.

A test for this issue was provided at 90e3ffd393

Date: 2021-10-22 08:28:00-07:00
Signed-off-by: meows <b5c6@protonmail.com>

* core: fix tests by adding GenesisDifficulty to expected result

See prior two commits.

Date: 2021-10-22 09:16:01-07:00
Signed-off-by: meows <b5c6@protonmail.com>

* les: fix test with genesis change
Co-authored-by: Martin Holst Swende <martin@swende.se>

xgo is not maintained at this time, so none of these builds work.

Closes #23784

This PR adds a new accessor method to the freezer database. This new view offers a consistent interface, guaranteeing that all individual tables (headers, bodies etc) are all on the same number, and that this number is not changes (added/truncated) while the operation is performing. 

- use Text instead of fmt.Sprintf
- reduced allocs from 6 to 2
- improved speed

This fixes a panic that occurs when HeaderByNumber() returns an error.

* core/state/snapshot: fix BAD BLOCK error when snapshot is generating

* core/state/snapshot: alternative fix for the snapshot generator

* add comments and minor update
Co-authored-by: Martin Holst Swende <martin@swende.se>

* core: fix warning flagging the use of DeepEqual on error

* apply the same change everywhere possible

* revert change that was committed by mistake

* fix build error

* Update config.go

* revert changes to ConfigCompatError

* review feedback
Co-authored-by: Felix Lange <fjl@twurst.com>

* cmd/evm: add 256-bit field validations on transactions (t9n)

* cmd/evm: validate gas*gasPrice, return intrinsic gas usage

* cmd/evm: address review comment

* cmd/utils: update flag description

* Update cmd/utils/flags.go
Co-authored-by: unkonwn-coder <unknown-coder@gmail.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>

* eth/fetcher: fix nilness check https://github.com/ethereum/go-ethereum/issues/23738

* eth/fetcher: Use errors.Is. PR feedback from @holiman.

* cmd/puppeth: use geth's prompt to read input

* remove wizard.in

* cmd/puppeth: fix compilation errors

* reset prompt (don't exit) on receiving ctrl-c

* make promptInput spin until the user enters a value or interrupts (ctrl-d)

* make promptInput use parameter
Co-authored-by: Martin Holst Swende <martin@swende.se>

* internal/ethapi: fix recover sender of pending transaction

* internal/ethapi: check if current exists

This PR adds support for the rlpdump tool to go from text format to RLP.

Adds suppor for passing regular strings to db `put`/`get`/`delete`, to avoid having to hex-encode when operating on fixed-key items like `SnapshotSyncStatus`, `SnapshotRecovery`  etc.
Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>