evmc::Host Class Reference

Abstract class to be used by Host implementations. More...

#include <evmc.hpp>

Inheritance diagram for evmc::Host:

Public Member Functions
evmc_host_context *	to_context () noexcept
	Converts the Host object to the opaque host context pointer.
Public Member Functions inherited from evmc::HostInterface
virtual bool	account_exists (const address &addr) const noexcept=0
	Check account existence callback function.
virtual bytes32	get_storage (const address &addr, const bytes32 &key) const noexcept=0
	Get storage callback function.
virtual evmc_storage_status	set_storage (const address &addr, const bytes32 &key, const bytes32 &value) noexcept=0
	Set storage callback function.
virtual uint256be	get_balance (const address &addr) const noexcept=0
	Get balance callback function.
virtual size_t	get_code_size (const address &addr) const noexcept=0
	Get code size callback function.
virtual bytes32	get_code_hash (const address &addr) const noexcept=0
	Get code hash callback function.
virtual size_t	copy_code (const address &addr, size_t code_offset, uint8_t *buffer_data, size_t buffer_size) const noexcept=0
	Copy code callback function.
virtual bool	selfdestruct (const address &addr, const address &beneficiary) noexcept=0
	Selfdestruct callback function.
virtual Result	call (const evmc_message &msg) noexcept=0
	Call callback function.
virtual evmc_tx_context	get_tx_context () const noexcept=0
	Get transaction context callback function.
virtual bytes32	get_block_hash (int64_t block_number) const noexcept=0
	Get block hash callback function.
virtual void	emit_log (const address &addr, const uint8_t *data, size_t data_size, const bytes32 topics[], size_t num_topics) noexcept=0
	Emit log callback function.
virtual evmc_access_status	access_account (const address &addr) noexcept=0
	Access account callback function.
virtual evmc_access_status	access_storage (const address &addr, const bytes32 &key) noexcept=0
	Access storage callback function.
virtual bytes32	get_transient_storage (const address &addr, const bytes32 &key) const noexcept=0
	Get transient storage callback function.
virtual void	set_transient_storage (const address &addr, const bytes32 &key, const bytes32 &value) noexcept=0
	Set transient storage callback function.

Static Public Member Functions
static const evmc_host_interface &	get_interface () noexcept
	Provides access to the global host interface.
template<typename DerivedClass = Host>
static DerivedClass *	from_context (evmc_host_context *context) noexcept
	Converts the opaque host context pointer back to the original Host object.

Detailed Description

Abstract class to be used by Host implementations.

When implementing EVMC Host, you can directly inherit from the evmc::Host class. This way your implementation will be simpler by avoiding manual handling of the evmc_host_context and the evmc_host_interface.

Definition at line 620 of file evmc.hpp.

Member Function Documentation

from_context()

template<typename DerivedClass = Host>

static DerivedClass * evmc::Host::from_context ( evmc_host_context *  context )

inlinestaticnoexcept

Converts the opaque host context pointer back to the original Host object.

Template Parameters

DerivedClass

The class derived from the Host class.

Parameters

context

The opaque host context pointer.

Returns

The pointer to DerivedClass.

Definition at line 636 of file evmc.hpp.

    {
        // Get pointer of the Host base class.
        auto* h = reinterpret_cast<Host*>(context);
 
        // Additional downcast, only possible if DerivedClass inherits from Host.
        return static_cast<DerivedClass*>(h);
    }

get_interface()

const evmc_host_interface & evmc::Host::get_interface ( )

inlinestaticnoexcept

Provides access to the global host interface.

Returns

Reference to the host interface object.

Definition at line 882 of file evmc.hpp.

{
    static constexpr evmc_host_interface interface = {
        ::evmc::internal::account_exists,
        ::evmc::internal::get_storage,
        ::evmc::internal::set_storage,
        ::evmc::internal::get_balance,
        ::evmc::internal::get_code_size,
        ::evmc::internal::get_code_hash,
        ::evmc::internal::copy_code,
        ::evmc::internal::selfdestruct,
        ::evmc::internal::call,
        ::evmc::internal::get_tx_context,
        ::evmc::internal::get_block_hash,
        ::evmc::internal::emit_log,
        ::evmc::internal::access_account,
        ::evmc::internal::access_storage,
        ::evmc::internal::get_transient_storage,
        ::evmc::internal::set_transient_storage,
    };
    return interface;
}

to_context()

evmc_host_context * evmc::Host::to_context ( )

inlinenoexcept

Converts the Host object to the opaque host context pointer.

Returns

Pointer to evmc_host_context.

Definition at line 629 of file evmc.hpp.

{ return reinterpret_cast<evmc_host_context*>(this); }

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The documentation for this class was generated from the following file:

• include/evmc/evmc.hpp