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author | Guillaume Ballet <gballet@gmail.com> | 2018-02-22 18:25:07 +0800 |
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committer | Péter Szilágyi <peterke@gmail.com> | 2018-02-22 18:25:07 +0800 |
commit | bb5349b15463255d269870fec9839a942eeecc1a (patch) | |
tree | 5b16e3a0abaa72daeab54d51d9997210bbd47f45 /whisper/whisperv2/topic.go | |
parent | 724a915470573ead1902df39150107ee1ff4f949 (diff) | |
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whisper: Support for v2 has long been discontinued, remove it. (#16153)
Diffstat (limited to 'whisper/whisperv2/topic.go')
-rw-r--r-- | whisper/whisperv2/topic.go | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/whisper/whisperv2/topic.go b/whisper/whisperv2/topic.go deleted file mode 100644 index 3e2b47bd3..000000000 --- a/whisper/whisperv2/topic.go +++ /dev/null @@ -1,140 +0,0 @@ -// Copyright 2015 The go-ethereum Authors -// This file is part of the go-ethereum library. -// -// The go-ethereum library is free software: you can redistribute it and/or modify -// it under the terms of the GNU Lesser General Public License as published by -// the Free Software Foundation, either version 3 of the License, or -// (at your option) any later version. -// -// The go-ethereum library is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -// GNU Lesser General Public License for more details. -// -// You should have received a copy of the GNU Lesser General Public License -// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. - -// Contains the Whisper protocol Topic element. For formal details please see -// the specs at https://github.com/ethereum/wiki/wiki/Whisper-PoC-1-Protocol-Spec#topics. - -package whisperv2 - -import "github.com/ethereum/go-ethereum/crypto" - -// Topic represents a cryptographically secure, probabilistic partial -// classifications of a message, determined as the first (left) 4 bytes of the -// SHA3 hash of some arbitrary data given by the original author of the message. -type Topic [4]byte - -// NewTopic creates a topic from the 4 byte prefix of the SHA3 hash of the data. -// -// Note, empty topics are considered the wildcard, and cannot be used in messages. -func NewTopic(data []byte) Topic { - prefix := [4]byte{} - copy(prefix[:], crypto.Keccak256(data)[:4]) - return Topic(prefix) -} - -// NewTopics creates a list of topics from a list of binary data elements, by -// iteratively calling NewTopic on each of them. -func NewTopics(data ...[]byte) []Topic { - topics := make([]Topic, len(data)) - for i, element := range data { - topics[i] = NewTopic(element) - } - return topics -} - -// NewTopicFromString creates a topic using the binary data contents of the -// specified string. -func NewTopicFromString(data string) Topic { - return NewTopic([]byte(data)) -} - -// NewTopicsFromStrings creates a list of topics from a list of textual data -// elements, by iteratively calling NewTopicFromString on each of them. -func NewTopicsFromStrings(data ...string) []Topic { - topics := make([]Topic, len(data)) - for i, element := range data { - topics[i] = NewTopicFromString(element) - } - return topics -} - -// String converts a topic byte array to a string representation. -func (self *Topic) String() string { - return string(self[:]) -} - -// topicMatcher is a filter expression to verify if a list of topics contained -// in an arriving message matches some topic conditions. The topic matcher is -// built up of a list of conditions, each of which must be satisfied by the -// corresponding topic in the message. Each condition may require: a) an exact -// topic match; b) a match from a set of topics; or c) a wild-card matching all. -// -// If a message contains more topics than required by the matcher, those beyond -// the condition count are ignored and assumed to match. -// -// Consider the following sample topic matcher: -// sample := { -// {TopicA1, TopicA2, TopicA3}, -// {TopicB}, -// nil, -// {TopicD1, TopicD2} -// } -// In order for a message to pass this filter, it should enumerate at least 4 -// topics, the first any of [TopicA1, TopicA2, TopicA3], the second mandatory -// "TopicB", the third is ignored by the filter and the fourth either "TopicD1" -// or "TopicD2". If the message contains further topics, the filter will match -// them too. -type topicMatcher struct { - conditions []map[Topic]struct{} -} - -// newTopicMatcher create a topic matcher from a list of topic conditions. -func newTopicMatcher(topics ...[]Topic) *topicMatcher { - matcher := make([]map[Topic]struct{}, len(topics)) - for i, condition := range topics { - matcher[i] = make(map[Topic]struct{}) - for _, topic := range condition { - matcher[i][topic] = struct{}{} - } - } - return &topicMatcher{conditions: matcher} -} - -// newTopicMatcherFromBinary create a topic matcher from a list of binary conditions. -func newTopicMatcherFromBinary(data ...[][]byte) *topicMatcher { - topics := make([][]Topic, len(data)) - for i, condition := range data { - topics[i] = NewTopics(condition...) - } - return newTopicMatcher(topics...) -} - -// newTopicMatcherFromStrings creates a topic matcher from a list of textual -// conditions. -func newTopicMatcherFromStrings(data ...[]string) *topicMatcher { - topics := make([][]Topic, len(data)) - for i, condition := range data { - topics[i] = NewTopicsFromStrings(condition...) - } - return newTopicMatcher(topics...) -} - -// Matches checks if a list of topics matches this particular condition set. -func (self *topicMatcher) Matches(topics []Topic) bool { - // Mismatch if there aren't enough topics - if len(self.conditions) > len(topics) { - return false - } - // Check each topic condition for existence (skip wild-cards) - for i := 0; i < len(topics) && i < len(self.conditions); i++ { - if len(self.conditions[i]) > 0 { - if _, ok := self.conditions[i][topics[i]]; !ok { - return false - } - } - } - return true -} |