github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
github.com/hashicorp/go-retryablehttp v0.7.0 // indirect
github.com/hashicorp/go-version v1.3.1
+ github.com/hashicorp/golang-lru v0.5.1
github.com/huandu/xstrings v1.3.2
github.com/issue9/identicon v1.2.0
github.com/jaytaylor/html2text v0.0.0-20200412013138-3577fbdbcff7
github.com/hashicorp/go-uuid v1.0.1/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
github.com/hashicorp/go.net v0.0.1/go.mod h1:hjKkEWcCURg++eb33jQU7oqQcI9XDCnUzHA0oac0k90=
github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
+github.com/hashicorp/golang-lru v0.5.1 h1:0hERBMJE1eitiLkihrMvRVBYAkpHzc/J3QdDN+dAcgU=
github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
import (
"bufio"
"bytes"
+ "fmt"
gohtml "html"
"path/filepath"
"strings"
"github.com/alecthomas/chroma/formatters/html"
"github.com/alecthomas/chroma/lexers"
"github.com/alecthomas/chroma/styles"
+ lru "github.com/hashicorp/golang-lru"
)
// don't index files larger than this many bytes for performance purposes
highlightMapping = map[string]string{}
once sync.Once
+
+ cache *lru.ARCCache
)
// NewContext loads custom highlight map from local config
for i := range keys {
highlightMapping[keys[i].Name()] = keys[i].Value()
}
+
+ // The size 512 is simply a conservative rule of thumb
+ c, err := lru.NewARC(512)
+ if err != nil {
+ panic(fmt.Sprintf("failed to initialize LRU cache for highlighter: %s", err))
+ }
+ cache = c
})
}
lexer = lexers.Get(val)
}
+ if lexer == nil {
+ if l, ok := cache.Get(fileName); ok {
+ lexer = l.(chroma.Lexer)
+ }
+ }
+
if lexer == nil {
lexer = lexers.Match(fileName)
if lexer == nil {
lexer = lexers.Fallback
}
+ cache.Add(fileName, lexer)
}
iterator, err := lexer.Tokenise(nil, string(code))
--- /dev/null
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test
--- /dev/null
+package lru
+
+import (
+ "fmt"
+ "sync"
+
+ "github.com/hashicorp/golang-lru/simplelru"
+)
+
+const (
+ // Default2QRecentRatio is the ratio of the 2Q cache dedicated
+ // to recently added entries that have only been accessed once.
+ Default2QRecentRatio = 0.25
+
+ // Default2QGhostEntries is the default ratio of ghost
+ // entries kept to track entries recently evicted
+ Default2QGhostEntries = 0.50
+)
+
+// TwoQueueCache is a thread-safe fixed size 2Q cache.
+// 2Q is an enhancement over the standard LRU cache
+// in that it tracks both frequently and recently used
+// entries separately. This avoids a burst in access to new
+// entries from evicting frequently used entries. It adds some
+// additional tracking overhead to the standard LRU cache, and is
+// computationally about 2x the cost, and adds some metadata over
+// head. The ARCCache is similar, but does not require setting any
+// parameters.
+type TwoQueueCache struct {
+ size int
+ recentSize int
+
+ recent simplelru.LRUCache
+ frequent simplelru.LRUCache
+ recentEvict simplelru.LRUCache
+ lock sync.RWMutex
+}
+
+// New2Q creates a new TwoQueueCache using the default
+// values for the parameters.
+func New2Q(size int) (*TwoQueueCache, error) {
+ return New2QParams(size, Default2QRecentRatio, Default2QGhostEntries)
+}
+
+// New2QParams creates a new TwoQueueCache using the provided
+// parameter values.
+func New2QParams(size int, recentRatio float64, ghostRatio float64) (*TwoQueueCache, error) {
+ if size <= 0 {
+ return nil, fmt.Errorf("invalid size")
+ }
+ if recentRatio < 0.0 || recentRatio > 1.0 {
+ return nil, fmt.Errorf("invalid recent ratio")
+ }
+ if ghostRatio < 0.0 || ghostRatio > 1.0 {
+ return nil, fmt.Errorf("invalid ghost ratio")
+ }
+
+ // Determine the sub-sizes
+ recentSize := int(float64(size) * recentRatio)
+ evictSize := int(float64(size) * ghostRatio)
+
+ // Allocate the LRUs
+ recent, err := simplelru.NewLRU(size, nil)
+ if err != nil {
+ return nil, err
+ }
+ frequent, err := simplelru.NewLRU(size, nil)
+ if err != nil {
+ return nil, err
+ }
+ recentEvict, err := simplelru.NewLRU(evictSize, nil)
+ if err != nil {
+ return nil, err
+ }
+
+ // Initialize the cache
+ c := &TwoQueueCache{
+ size: size,
+ recentSize: recentSize,
+ recent: recent,
+ frequent: frequent,
+ recentEvict: recentEvict,
+ }
+ return c, nil
+}
+
+// Get looks up a key's value from the cache.
+func (c *TwoQueueCache) Get(key interface{}) (value interface{}, ok bool) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ // Check if this is a frequent value
+ if val, ok := c.frequent.Get(key); ok {
+ return val, ok
+ }
+
+ // If the value is contained in recent, then we
+ // promote it to frequent
+ if val, ok := c.recent.Peek(key); ok {
+ c.recent.Remove(key)
+ c.frequent.Add(key, val)
+ return val, ok
+ }
+
+ // No hit
+ return nil, false
+}
+
+// Add adds a value to the cache.
+func (c *TwoQueueCache) Add(key, value interface{}) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ // Check if the value is frequently used already,
+ // and just update the value
+ if c.frequent.Contains(key) {
+ c.frequent.Add(key, value)
+ return
+ }
+
+ // Check if the value is recently used, and promote
+ // the value into the frequent list
+ if c.recent.Contains(key) {
+ c.recent.Remove(key)
+ c.frequent.Add(key, value)
+ return
+ }
+
+ // If the value was recently evicted, add it to the
+ // frequently used list
+ if c.recentEvict.Contains(key) {
+ c.ensureSpace(true)
+ c.recentEvict.Remove(key)
+ c.frequent.Add(key, value)
+ return
+ }
+
+ // Add to the recently seen list
+ c.ensureSpace(false)
+ c.recent.Add(key, value)
+ return
+}
+
+// ensureSpace is used to ensure we have space in the cache
+func (c *TwoQueueCache) ensureSpace(recentEvict bool) {
+ // If we have space, nothing to do
+ recentLen := c.recent.Len()
+ freqLen := c.frequent.Len()
+ if recentLen+freqLen < c.size {
+ return
+ }
+
+ // If the recent buffer is larger than
+ // the target, evict from there
+ if recentLen > 0 && (recentLen > c.recentSize || (recentLen == c.recentSize && !recentEvict)) {
+ k, _, _ := c.recent.RemoveOldest()
+ c.recentEvict.Add(k, nil)
+ return
+ }
+
+ // Remove from the frequent list otherwise
+ c.frequent.RemoveOldest()
+}
+
+// Len returns the number of items in the cache.
+func (c *TwoQueueCache) Len() int {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ return c.recent.Len() + c.frequent.Len()
+}
+
+// Keys returns a slice of the keys in the cache.
+// The frequently used keys are first in the returned slice.
+func (c *TwoQueueCache) Keys() []interface{} {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ k1 := c.frequent.Keys()
+ k2 := c.recent.Keys()
+ return append(k1, k2...)
+}
+
+// Remove removes the provided key from the cache.
+func (c *TwoQueueCache) Remove(key interface{}) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ if c.frequent.Remove(key) {
+ return
+ }
+ if c.recent.Remove(key) {
+ return
+ }
+ if c.recentEvict.Remove(key) {
+ return
+ }
+}
+
+// Purge is used to completely clear the cache.
+func (c *TwoQueueCache) Purge() {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ c.recent.Purge()
+ c.frequent.Purge()
+ c.recentEvict.Purge()
+}
+
+// Contains is used to check if the cache contains a key
+// without updating recency or frequency.
+func (c *TwoQueueCache) Contains(key interface{}) bool {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ return c.frequent.Contains(key) || c.recent.Contains(key)
+}
+
+// Peek is used to inspect the cache value of a key
+// without updating recency or frequency.
+func (c *TwoQueueCache) Peek(key interface{}) (value interface{}, ok bool) {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ if val, ok := c.frequent.Peek(key); ok {
+ return val, ok
+ }
+ return c.recent.Peek(key)
+}
--- /dev/null
+Mozilla Public License, version 2.0
+
+1. Definitions
+
+1.1. "Contributor"
+
+ means each individual or legal entity that creates, contributes to the
+ creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+
+ means the combination of the Contributions of others (if any) used by a
+ Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+
+ means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+
+ means Source Code Form to which the initial Contributor has attached the
+ notice in Exhibit A, the Executable Form of such Source Code Form, and
+ Modifications of such Source Code Form, in each case including portions
+ thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+ means
+
+ a. that the initial Contributor has attached the notice described in
+ Exhibit B to the Covered Software; or
+
+ b. that the Covered Software was made available under the terms of
+ version 1.1 or earlier of the License, but not also under the terms of
+ a Secondary License.
+
+1.6. "Executable Form"
+
+ means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+
+ means a work that combines Covered Software with other material, in a
+ separate file or files, that is not Covered Software.
+
+1.8. "License"
+
+ means this document.
+
+1.9. "Licensable"
+
+ means having the right to grant, to the maximum extent possible, whether
+ at the time of the initial grant or subsequently, any and all of the
+ rights conveyed by this License.
+
+1.10. "Modifications"
+
+ means any of the following:
+
+ a. any file in Source Code Form that results from an addition to,
+ deletion from, or modification of the contents of Covered Software; or
+
+ b. any new file in Source Code Form that contains any Covered Software.
+
+1.11. "Patent Claims" of a Contributor
+
+ means any patent claim(s), including without limitation, method,
+ process, and apparatus claims, in any patent Licensable by such
+ Contributor that would be infringed, but for the grant of the License,
+ by the making, using, selling, offering for sale, having made, import,
+ or transfer of either its Contributions or its Contributor Version.
+
+1.12. "Secondary License"
+
+ means either the GNU General Public License, Version 2.0, the GNU Lesser
+ General Public License, Version 2.1, the GNU Affero General Public
+ License, Version 3.0, or any later versions of those licenses.
+
+1.13. "Source Code Form"
+
+ means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+
+ means an individual or a legal entity exercising rights under this
+ License. For legal entities, "You" includes any entity that controls, is
+ controlled by, or is under common control with You. For purposes of this
+ definition, "control" means (a) the power, direct or indirect, to cause
+ the direction or management of such entity, whether by contract or
+ otherwise, or (b) ownership of more than fifty percent (50%) of the
+ outstanding shares or beneficial ownership of such entity.
+
+
+2. License Grants and Conditions
+
+2.1. Grants
+
+ Each Contributor hereby grants You a world-wide, royalty-free,
+ non-exclusive license:
+
+ a. under intellectual property rights (other than patent or trademark)
+ Licensable by such Contributor to use, reproduce, make available,
+ modify, display, perform, distribute, and otherwise exploit its
+ Contributions, either on an unmodified basis, with Modifications, or
+ as part of a Larger Work; and
+
+ b. under Patent Claims of such Contributor to make, use, sell, offer for
+ sale, have made, import, and otherwise transfer either its
+ Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+ The licenses granted in Section 2.1 with respect to any Contribution
+ become effective for each Contribution on the date the Contributor first
+ distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+ The licenses granted in this Section 2 are the only rights granted under
+ this License. No additional rights or licenses will be implied from the
+ distribution or licensing of Covered Software under this License.
+ Notwithstanding Section 2.1(b) above, no patent license is granted by a
+ Contributor:
+
+ a. for any code that a Contributor has removed from Covered Software; or
+
+ b. for infringements caused by: (i) Your and any other third party's
+ modifications of Covered Software, or (ii) the combination of its
+ Contributions with other software (except as part of its Contributor
+ Version); or
+
+ c. under Patent Claims infringed by Covered Software in the absence of
+ its Contributions.
+
+ This License does not grant any rights in the trademarks, service marks,
+ or logos of any Contributor (except as may be necessary to comply with
+ the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+ No Contributor makes additional grants as a result of Your choice to
+ distribute the Covered Software under a subsequent version of this
+ License (see Section 10.2) or under the terms of a Secondary License (if
+ permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+ Each Contributor represents that the Contributor believes its
+ Contributions are its original creation(s) or it has sufficient rights to
+ grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+ This License is not intended to limit any rights You have under
+ applicable copyright doctrines of fair use, fair dealing, or other
+ equivalents.
+
+2.7. Conditions
+
+ Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in
+ Section 2.1.
+
+
+3. Responsibilities
+
+3.1. Distribution of Source Form
+
+ All distribution of Covered Software in Source Code Form, including any
+ Modifications that You create or to which You contribute, must be under
+ the terms of this License. You must inform recipients that the Source
+ Code Form of the Covered Software is governed by the terms of this
+ License, and how they can obtain a copy of this License. You may not
+ attempt to alter or restrict the recipients' rights in the Source Code
+ Form.
+
+3.2. Distribution of Executable Form
+
+ If You distribute Covered Software in Executable Form then:
+
+ a. such Covered Software must also be made available in Source Code Form,
+ as described in Section 3.1, and You must inform recipients of the
+ Executable Form how they can obtain a copy of such Source Code Form by
+ reasonable means in a timely manner, at a charge no more than the cost
+ of distribution to the recipient; and
+
+ b. You may distribute such Executable Form under the terms of this
+ License, or sublicense it under different terms, provided that the
+ license for the Executable Form does not attempt to limit or alter the
+ recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+ You may create and distribute a Larger Work under terms of Your choice,
+ provided that You also comply with the requirements of this License for
+ the Covered Software. If the Larger Work is a combination of Covered
+ Software with a work governed by one or more Secondary Licenses, and the
+ Covered Software is not Incompatible With Secondary Licenses, this
+ License permits You to additionally distribute such Covered Software
+ under the terms of such Secondary License(s), so that the recipient of
+ the Larger Work may, at their option, further distribute the Covered
+ Software under the terms of either this License or such Secondary
+ License(s).
+
+3.4. Notices
+
+ You may not remove or alter the substance of any license notices
+ (including copyright notices, patent notices, disclaimers of warranty, or
+ limitations of liability) contained within the Source Code Form of the
+ Covered Software, except that You may alter any license notices to the
+ extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+ You may choose to offer, and to charge a fee for, warranty, support,
+ indemnity or liability obligations to one or more recipients of Covered
+ Software. However, You may do so only on Your own behalf, and not on
+ behalf of any Contributor. You must make it absolutely clear that any
+ such warranty, support, indemnity, or liability obligation is offered by
+ You alone, and You hereby agree to indemnify every Contributor for any
+ liability incurred by such Contributor as a result of warranty, support,
+ indemnity or liability terms You offer. You may include additional
+ disclaimers of warranty and limitations of liability specific to any
+ jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+
+ If it is impossible for You to comply with any of the terms of this License
+ with respect to some or all of the Covered Software due to statute,
+ judicial order, or regulation then You must: (a) comply with the terms of
+ this License to the maximum extent possible; and (b) describe the
+ limitations and the code they affect. Such description must be placed in a
+ text file included with all distributions of the Covered Software under
+ this License. Except to the extent prohibited by statute or regulation,
+ such description must be sufficiently detailed for a recipient of ordinary
+ skill to be able to understand it.
+
+5. Termination
+
+5.1. The rights granted under this License will terminate automatically if You
+ fail to comply with any of its terms. However, if You become compliant,
+ then the rights granted under this License from a particular Contributor
+ are reinstated (a) provisionally, unless and until such Contributor
+ explicitly and finally terminates Your grants, and (b) on an ongoing
+ basis, if such Contributor fails to notify You of the non-compliance by
+ some reasonable means prior to 60 days after You have come back into
+ compliance. Moreover, Your grants from a particular Contributor are
+ reinstated on an ongoing basis if such Contributor notifies You of the
+ non-compliance by some reasonable means, this is the first time You have
+ received notice of non-compliance with this License from such
+ Contributor, and You become compliant prior to 30 days after Your receipt
+ of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+ infringement claim (excluding declaratory judgment actions,
+ counter-claims, and cross-claims) alleging that a Contributor Version
+ directly or indirectly infringes any patent, then the rights granted to
+ You by any and all Contributors for the Covered Software under Section
+ 2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all end user
+ license agreements (excluding distributors and resellers) which have been
+ validly granted by You or Your distributors under this License prior to
+ termination shall survive termination.
+
+6. Disclaimer of Warranty
+
+ Covered Software is provided under this License on an "as is" basis,
+ without warranty of any kind, either expressed, implied, or statutory,
+ including, without limitation, warranties that the Covered Software is free
+ of defects, merchantable, fit for a particular purpose or non-infringing.
+ The entire risk as to the quality and performance of the Covered Software
+ is with You. Should any Covered Software prove defective in any respect,
+ You (not any Contributor) assume the cost of any necessary servicing,
+ repair, or correction. This disclaimer of warranty constitutes an essential
+ part of this License. No use of any Covered Software is authorized under
+ this License except under this disclaimer.
+
+7. Limitation of Liability
+
+ Under no circumstances and under no legal theory, whether tort (including
+ negligence), contract, or otherwise, shall any Contributor, or anyone who
+ distributes Covered Software as permitted above, be liable to You for any
+ direct, indirect, special, incidental, or consequential damages of any
+ character including, without limitation, damages for lost profits, loss of
+ goodwill, work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses, even if such party shall have been
+ informed of the possibility of such damages. This limitation of liability
+ shall not apply to liability for death or personal injury resulting from
+ such party's negligence to the extent applicable law prohibits such
+ limitation. Some jurisdictions do not allow the exclusion or limitation of
+ incidental or consequential damages, so this exclusion and limitation may
+ not apply to You.
+
+8. Litigation
+
+ Any litigation relating to this License may be brought only in the courts
+ of a jurisdiction where the defendant maintains its principal place of
+ business and such litigation shall be governed by laws of that
+ jurisdiction, without reference to its conflict-of-law provisions. Nothing
+ in this Section shall prevent a party's ability to bring cross-claims or
+ counter-claims.
+
+9. Miscellaneous
+
+ This License represents the complete agreement concerning the subject
+ matter hereof. If any provision of this License is held to be
+ unenforceable, such provision shall be reformed only to the extent
+ necessary to make it enforceable. Any law or regulation which provides that
+ the language of a contract shall be construed against the drafter shall not
+ be used to construe this License against a Contributor.
+
+
+10. Versions of the License
+
+10.1. New Versions
+
+ Mozilla Foundation is the license steward. Except as provided in Section
+ 10.3, no one other than the license steward has the right to modify or
+ publish new versions of this License. Each version will be given a
+ distinguishing version number.
+
+10.2. Effect of New Versions
+
+ You may distribute the Covered Software under the terms of the version
+ of the License under which You originally received the Covered Software,
+ or under the terms of any subsequent version published by the license
+ steward.
+
+10.3. Modified Versions
+
+ If you create software not governed by this License, and you want to
+ create a new license for such software, you may create and use a
+ modified version of this License if you rename the license and remove
+ any references to the name of the license steward (except to note that
+ such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+ Licenses If You choose to distribute Source Code Form that is
+ Incompatible With Secondary Licenses under the terms of this version of
+ the License, the notice described in Exhibit B of this License must be
+ attached.
+
+Exhibit A - Source Code Form License Notice
+
+ This Source Code Form is subject to the
+ terms of the Mozilla Public License, v.
+ 2.0. If a copy of the MPL was not
+ distributed with this file, You can
+ obtain one at
+ http://mozilla.org/MPL/2.0/.
+
+If it is not possible or desirable to put the notice in a particular file,
+then You may include the notice in a location (such as a LICENSE file in a
+relevant directory) where a recipient would be likely to look for such a
+notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+
+ This Source Code Form is "Incompatible
+ With Secondary Licenses", as defined by
+ the Mozilla Public License, v. 2.0.
--- /dev/null
+golang-lru
+==========
+
+This provides the `lru` package which implements a fixed-size
+thread safe LRU cache. It is based on the cache in Groupcache.
+
+Documentation
+=============
+
+Full docs are available on [Godoc](http://godoc.org/github.com/hashicorp/golang-lru)
+
+Example
+=======
+
+Using the LRU is very simple:
+
+```go
+l, _ := New(128)
+for i := 0; i < 256; i++ {
+ l.Add(i, nil)
+}
+if l.Len() != 128 {
+ panic(fmt.Sprintf("bad len: %v", l.Len()))
+}
+```
--- /dev/null
+package lru
+
+import (
+ "sync"
+
+ "github.com/hashicorp/golang-lru/simplelru"
+)
+
+// ARCCache is a thread-safe fixed size Adaptive Replacement Cache (ARC).
+// ARC is an enhancement over the standard LRU cache in that tracks both
+// frequency and recency of use. This avoids a burst in access to new
+// entries from evicting the frequently used older entries. It adds some
+// additional tracking overhead to a standard LRU cache, computationally
+// it is roughly 2x the cost, and the extra memory overhead is linear
+// with the size of the cache. ARC has been patented by IBM, but is
+// similar to the TwoQueueCache (2Q) which requires setting parameters.
+type ARCCache struct {
+ size int // Size is the total capacity of the cache
+ p int // P is the dynamic preference towards T1 or T2
+
+ t1 simplelru.LRUCache // T1 is the LRU for recently accessed items
+ b1 simplelru.LRUCache // B1 is the LRU for evictions from t1
+
+ t2 simplelru.LRUCache // T2 is the LRU for frequently accessed items
+ b2 simplelru.LRUCache // B2 is the LRU for evictions from t2
+
+ lock sync.RWMutex
+}
+
+// NewARC creates an ARC of the given size
+func NewARC(size int) (*ARCCache, error) {
+ // Create the sub LRUs
+ b1, err := simplelru.NewLRU(size, nil)
+ if err != nil {
+ return nil, err
+ }
+ b2, err := simplelru.NewLRU(size, nil)
+ if err != nil {
+ return nil, err
+ }
+ t1, err := simplelru.NewLRU(size, nil)
+ if err != nil {
+ return nil, err
+ }
+ t2, err := simplelru.NewLRU(size, nil)
+ if err != nil {
+ return nil, err
+ }
+
+ // Initialize the ARC
+ c := &ARCCache{
+ size: size,
+ p: 0,
+ t1: t1,
+ b1: b1,
+ t2: t2,
+ b2: b2,
+ }
+ return c, nil
+}
+
+// Get looks up a key's value from the cache.
+func (c *ARCCache) Get(key interface{}) (value interface{}, ok bool) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ // If the value is contained in T1 (recent), then
+ // promote it to T2 (frequent)
+ if val, ok := c.t1.Peek(key); ok {
+ c.t1.Remove(key)
+ c.t2.Add(key, val)
+ return val, ok
+ }
+
+ // Check if the value is contained in T2 (frequent)
+ if val, ok := c.t2.Get(key); ok {
+ return val, ok
+ }
+
+ // No hit
+ return nil, false
+}
+
+// Add adds a value to the cache.
+func (c *ARCCache) Add(key, value interface{}) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ // Check if the value is contained in T1 (recent), and potentially
+ // promote it to frequent T2
+ if c.t1.Contains(key) {
+ c.t1.Remove(key)
+ c.t2.Add(key, value)
+ return
+ }
+
+ // Check if the value is already in T2 (frequent) and update it
+ if c.t2.Contains(key) {
+ c.t2.Add(key, value)
+ return
+ }
+
+ // Check if this value was recently evicted as part of the
+ // recently used list
+ if c.b1.Contains(key) {
+ // T1 set is too small, increase P appropriately
+ delta := 1
+ b1Len := c.b1.Len()
+ b2Len := c.b2.Len()
+ if b2Len > b1Len {
+ delta = b2Len / b1Len
+ }
+ if c.p+delta >= c.size {
+ c.p = c.size
+ } else {
+ c.p += delta
+ }
+
+ // Potentially need to make room in the cache
+ if c.t1.Len()+c.t2.Len() >= c.size {
+ c.replace(false)
+ }
+
+ // Remove from B1
+ c.b1.Remove(key)
+
+ // Add the key to the frequently used list
+ c.t2.Add(key, value)
+ return
+ }
+
+ // Check if this value was recently evicted as part of the
+ // frequently used list
+ if c.b2.Contains(key) {
+ // T2 set is too small, decrease P appropriately
+ delta := 1
+ b1Len := c.b1.Len()
+ b2Len := c.b2.Len()
+ if b1Len > b2Len {
+ delta = b1Len / b2Len
+ }
+ if delta >= c.p {
+ c.p = 0
+ } else {
+ c.p -= delta
+ }
+
+ // Potentially need to make room in the cache
+ if c.t1.Len()+c.t2.Len() >= c.size {
+ c.replace(true)
+ }
+
+ // Remove from B2
+ c.b2.Remove(key)
+
+ // Add the key to the frequently used list
+ c.t2.Add(key, value)
+ return
+ }
+
+ // Potentially need to make room in the cache
+ if c.t1.Len()+c.t2.Len() >= c.size {
+ c.replace(false)
+ }
+
+ // Keep the size of the ghost buffers trim
+ if c.b1.Len() > c.size-c.p {
+ c.b1.RemoveOldest()
+ }
+ if c.b2.Len() > c.p {
+ c.b2.RemoveOldest()
+ }
+
+ // Add to the recently seen list
+ c.t1.Add(key, value)
+ return
+}
+
+// replace is used to adaptively evict from either T1 or T2
+// based on the current learned value of P
+func (c *ARCCache) replace(b2ContainsKey bool) {
+ t1Len := c.t1.Len()
+ if t1Len > 0 && (t1Len > c.p || (t1Len == c.p && b2ContainsKey)) {
+ k, _, ok := c.t1.RemoveOldest()
+ if ok {
+ c.b1.Add(k, nil)
+ }
+ } else {
+ k, _, ok := c.t2.RemoveOldest()
+ if ok {
+ c.b2.Add(k, nil)
+ }
+ }
+}
+
+// Len returns the number of cached entries
+func (c *ARCCache) Len() int {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ return c.t1.Len() + c.t2.Len()
+}
+
+// Keys returns all the cached keys
+func (c *ARCCache) Keys() []interface{} {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ k1 := c.t1.Keys()
+ k2 := c.t2.Keys()
+ return append(k1, k2...)
+}
+
+// Remove is used to purge a key from the cache
+func (c *ARCCache) Remove(key interface{}) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ if c.t1.Remove(key) {
+ return
+ }
+ if c.t2.Remove(key) {
+ return
+ }
+ if c.b1.Remove(key) {
+ return
+ }
+ if c.b2.Remove(key) {
+ return
+ }
+}
+
+// Purge is used to clear the cache
+func (c *ARCCache) Purge() {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ c.t1.Purge()
+ c.t2.Purge()
+ c.b1.Purge()
+ c.b2.Purge()
+}
+
+// Contains is used to check if the cache contains a key
+// without updating recency or frequency.
+func (c *ARCCache) Contains(key interface{}) bool {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ return c.t1.Contains(key) || c.t2.Contains(key)
+}
+
+// Peek is used to inspect the cache value of a key
+// without updating recency or frequency.
+func (c *ARCCache) Peek(key interface{}) (value interface{}, ok bool) {
+ c.lock.RLock()
+ defer c.lock.RUnlock()
+ if val, ok := c.t1.Peek(key); ok {
+ return val, ok
+ }
+ return c.t2.Peek(key)
+}
--- /dev/null
+// Package lru provides three different LRU caches of varying sophistication.
+//
+// Cache is a simple LRU cache. It is based on the
+// LRU implementation in groupcache:
+// https://github.com/golang/groupcache/tree/master/lru
+//
+// TwoQueueCache tracks frequently used and recently used entries separately.
+// This avoids a burst of accesses from taking out frequently used entries,
+// at the cost of about 2x computational overhead and some extra bookkeeping.
+//
+// ARCCache is an adaptive replacement cache. It tracks recent evictions as
+// well as recent usage in both the frequent and recent caches. Its
+// computational overhead is comparable to TwoQueueCache, but the memory
+// overhead is linear with the size of the cache.
+//
+// ARC has been patented by IBM, so do not use it if that is problematic for
+// your program.
+//
+// All caches in this package take locks while operating, and are therefore
+// thread-safe for consumers.
+package lru
--- /dev/null
+module github.com/hashicorp/golang-lru
--- /dev/null
+package lru
+
+import (
+ "sync"
+
+ "github.com/hashicorp/golang-lru/simplelru"
+)
+
+// Cache is a thread-safe fixed size LRU cache.
+type Cache struct {
+ lru simplelru.LRUCache
+ lock sync.RWMutex
+}
+
+// New creates an LRU of the given size.
+func New(size int) (*Cache, error) {
+ return NewWithEvict(size, nil)
+}
+
+// NewWithEvict constructs a fixed size cache with the given eviction
+// callback.
+func NewWithEvict(size int, onEvicted func(key interface{}, value interface{})) (*Cache, error) {
+ lru, err := simplelru.NewLRU(size, simplelru.EvictCallback(onEvicted))
+ if err != nil {
+ return nil, err
+ }
+ c := &Cache{
+ lru: lru,
+ }
+ return c, nil
+}
+
+// Purge is used to completely clear the cache.
+func (c *Cache) Purge() {
+ c.lock.Lock()
+ c.lru.Purge()
+ c.lock.Unlock()
+}
+
+// Add adds a value to the cache. Returns true if an eviction occurred.
+func (c *Cache) Add(key, value interface{}) (evicted bool) {
+ c.lock.Lock()
+ evicted = c.lru.Add(key, value)
+ c.lock.Unlock()
+ return evicted
+}
+
+// Get looks up a key's value from the cache.
+func (c *Cache) Get(key interface{}) (value interface{}, ok bool) {
+ c.lock.Lock()
+ value, ok = c.lru.Get(key)
+ c.lock.Unlock()
+ return value, ok
+}
+
+// Contains checks if a key is in the cache, without updating the
+// recent-ness or deleting it for being stale.
+func (c *Cache) Contains(key interface{}) bool {
+ c.lock.RLock()
+ containKey := c.lru.Contains(key)
+ c.lock.RUnlock()
+ return containKey
+}
+
+// Peek returns the key value (or undefined if not found) without updating
+// the "recently used"-ness of the key.
+func (c *Cache) Peek(key interface{}) (value interface{}, ok bool) {
+ c.lock.RLock()
+ value, ok = c.lru.Peek(key)
+ c.lock.RUnlock()
+ return value, ok
+}
+
+// ContainsOrAdd checks if a key is in the cache without updating the
+// recent-ness or deleting it for being stale, and if not, adds the value.
+// Returns whether found and whether an eviction occurred.
+func (c *Cache) ContainsOrAdd(key, value interface{}) (ok, evicted bool) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ if c.lru.Contains(key) {
+ return true, false
+ }
+ evicted = c.lru.Add(key, value)
+ return false, evicted
+}
+
+// Remove removes the provided key from the cache.
+func (c *Cache) Remove(key interface{}) {
+ c.lock.Lock()
+ c.lru.Remove(key)
+ c.lock.Unlock()
+}
+
+// RemoveOldest removes the oldest item from the cache.
+func (c *Cache) RemoveOldest() {
+ c.lock.Lock()
+ c.lru.RemoveOldest()
+ c.lock.Unlock()
+}
+
+// Keys returns a slice of the keys in the cache, from oldest to newest.
+func (c *Cache) Keys() []interface{} {
+ c.lock.RLock()
+ keys := c.lru.Keys()
+ c.lock.RUnlock()
+ return keys
+}
+
+// Len returns the number of items in the cache.
+func (c *Cache) Len() int {
+ c.lock.RLock()
+ length := c.lru.Len()
+ c.lock.RUnlock()
+ return length
+}
--- /dev/null
+package simplelru
+
+import (
+ "container/list"
+ "errors"
+)
+
+// EvictCallback is used to get a callback when a cache entry is evicted
+type EvictCallback func(key interface{}, value interface{})
+
+// LRU implements a non-thread safe fixed size LRU cache
+type LRU struct {
+ size int
+ evictList *list.List
+ items map[interface{}]*list.Element
+ onEvict EvictCallback
+}
+
+// entry is used to hold a value in the evictList
+type entry struct {
+ key interface{}
+ value interface{}
+}
+
+// NewLRU constructs an LRU of the given size
+func NewLRU(size int, onEvict EvictCallback) (*LRU, error) {
+ if size <= 0 {
+ return nil, errors.New("Must provide a positive size")
+ }
+ c := &LRU{
+ size: size,
+ evictList: list.New(),
+ items: make(map[interface{}]*list.Element),
+ onEvict: onEvict,
+ }
+ return c, nil
+}
+
+// Purge is used to completely clear the cache.
+func (c *LRU) Purge() {
+ for k, v := range c.items {
+ if c.onEvict != nil {
+ c.onEvict(k, v.Value.(*entry).value)
+ }
+ delete(c.items, k)
+ }
+ c.evictList.Init()
+}
+
+// Add adds a value to the cache. Returns true if an eviction occurred.
+func (c *LRU) Add(key, value interface{}) (evicted bool) {
+ // Check for existing item
+ if ent, ok := c.items[key]; ok {
+ c.evictList.MoveToFront(ent)
+ ent.Value.(*entry).value = value
+ return false
+ }
+
+ // Add new item
+ ent := &entry{key, value}
+ entry := c.evictList.PushFront(ent)
+ c.items[key] = entry
+
+ evict := c.evictList.Len() > c.size
+ // Verify size not exceeded
+ if evict {
+ c.removeOldest()
+ }
+ return evict
+}
+
+// Get looks up a key's value from the cache.
+func (c *LRU) Get(key interface{}) (value interface{}, ok bool) {
+ if ent, ok := c.items[key]; ok {
+ c.evictList.MoveToFront(ent)
+ return ent.Value.(*entry).value, true
+ }
+ return
+}
+
+// Contains checks if a key is in the cache, without updating the recent-ness
+// or deleting it for being stale.
+func (c *LRU) Contains(key interface{}) (ok bool) {
+ _, ok = c.items[key]
+ return ok
+}
+
+// Peek returns the key value (or undefined if not found) without updating
+// the "recently used"-ness of the key.
+func (c *LRU) Peek(key interface{}) (value interface{}, ok bool) {
+ var ent *list.Element
+ if ent, ok = c.items[key]; ok {
+ return ent.Value.(*entry).value, true
+ }
+ return nil, ok
+}
+
+// Remove removes the provided key from the cache, returning if the
+// key was contained.
+func (c *LRU) Remove(key interface{}) (present bool) {
+ if ent, ok := c.items[key]; ok {
+ c.removeElement(ent)
+ return true
+ }
+ return false
+}
+
+// RemoveOldest removes the oldest item from the cache.
+func (c *LRU) RemoveOldest() (key interface{}, value interface{}, ok bool) {
+ ent := c.evictList.Back()
+ if ent != nil {
+ c.removeElement(ent)
+ kv := ent.Value.(*entry)
+ return kv.key, kv.value, true
+ }
+ return nil, nil, false
+}
+
+// GetOldest returns the oldest entry
+func (c *LRU) GetOldest() (key interface{}, value interface{}, ok bool) {
+ ent := c.evictList.Back()
+ if ent != nil {
+ kv := ent.Value.(*entry)
+ return kv.key, kv.value, true
+ }
+ return nil, nil, false
+}
+
+// Keys returns a slice of the keys in the cache, from oldest to newest.
+func (c *LRU) Keys() []interface{} {
+ keys := make([]interface{}, len(c.items))
+ i := 0
+ for ent := c.evictList.Back(); ent != nil; ent = ent.Prev() {
+ keys[i] = ent.Value.(*entry).key
+ i++
+ }
+ return keys
+}
+
+// Len returns the number of items in the cache.
+func (c *LRU) Len() int {
+ return c.evictList.Len()
+}
+
+// removeOldest removes the oldest item from the cache.
+func (c *LRU) removeOldest() {
+ ent := c.evictList.Back()
+ if ent != nil {
+ c.removeElement(ent)
+ }
+}
+
+// removeElement is used to remove a given list element from the cache
+func (c *LRU) removeElement(e *list.Element) {
+ c.evictList.Remove(e)
+ kv := e.Value.(*entry)
+ delete(c.items, kv.key)
+ if c.onEvict != nil {
+ c.onEvict(kv.key, kv.value)
+ }
+}
--- /dev/null
+package simplelru
+
+// LRUCache is the interface for simple LRU cache.
+type LRUCache interface {
+ // Adds a value to the cache, returns true if an eviction occurred and
+ // updates the "recently used"-ness of the key.
+ Add(key, value interface{}) bool
+
+ // Returns key's value from the cache and
+ // updates the "recently used"-ness of the key. #value, isFound
+ Get(key interface{}) (value interface{}, ok bool)
+
+ // Check if a key exsists in cache without updating the recent-ness.
+ Contains(key interface{}) (ok bool)
+
+ // Returns key's value without updating the "recently used"-ness of the key.
+ Peek(key interface{}) (value interface{}, ok bool)
+
+ // Removes a key from the cache.
+ Remove(key interface{}) bool
+
+ // Removes the oldest entry from cache.
+ RemoveOldest() (interface{}, interface{}, bool)
+
+ // Returns the oldest entry from the cache. #key, value, isFound
+ GetOldest() (interface{}, interface{}, bool)
+
+ // Returns a slice of the keys in the cache, from oldest to newest.
+ Keys() []interface{}
+
+ // Returns the number of items in the cache.
+ Len() int
+
+ // Clear all cache entries
+ Purge()
+}
# github.com/hashicorp/go-version v1.3.1 => github.com/6543/go-version v1.3.1
## explicit
github.com/hashicorp/go-version
+# github.com/hashicorp/golang-lru v0.5.1
+## explicit
+github.com/hashicorp/golang-lru
+github.com/hashicorp/golang-lru/simplelru
# github.com/hashicorp/hcl v1.0.0
github.com/hashicorp/hcl
github.com/hashicorp/hcl/hcl/ast