github.com/m3db/m3@v1.5.1-0.20231129193456-75a402aa583b/src/x/resource/types.go (about) 1 // Copyright (c) 2018 Uber Technologies, Inc. 2 // 3 // Permission is hereby granted, free of charge, to any person obtaining a copy 4 // of this software and associated documentation files (the "Software"), to deal 5 // in the Software without restriction, including without limitation the rights 6 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 // copies of the Software, and to permit persons to whom the Software is 8 // furnished to do so, subject to the following conditions: 9 // 10 // The above copyright notice and this permission notice shall be included in 11 // all copies or substantial portions of the Software. 12 // 13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 // THE SOFTWARE. 20 21 // Package resource describes require for object lifecycle management. 22 // Both Finalizer and Closer have similar concepts, they both exist so that 23 // different types can be used for resource cleanup with different method names 24 // as for some things like iterators, the verb close makes more sense than 25 // finalize and is more consistent with other types. 26 package resource 27 28 // Finalizer finalizes a checked resource. 29 type Finalizer interface { 30 Finalize() 31 } 32 33 // FinalizerFn is a function literal that is a finalizer. 34 type FinalizerFn func() 35 36 // Finalize will call the function literal as a finalizer. 37 func (fn FinalizerFn) Finalize() { 38 fn() 39 } 40 41 // SimpleCloser is an object that can be closed. 42 type SimpleCloser interface { 43 Close() 44 } 45 46 // SimpleCloserFn is a function literal that is a closer. 47 type SimpleCloserFn func() 48 49 // Close will call the function literal as a closer. 50 func (fn SimpleCloserFn) Close() { 51 fn() 52 } 53 54 // Closer is an object that can be closed which returns an error. 55 type Closer interface { 56 Close() error 57 } 58 59 // CloserFn is a function literal that is a closer which returns an error. 60 type CloserFn func() error 61 62 // Close will call the function literal as a closer. 63 func (fn CloserFn) Close() error { 64 return fn() 65 } 66 67 // NoopCloser is a no-op closer. 68 type NoopCloser struct { 69 // Calls is the number of times this closer was called. 70 Calls int 71 } 72 73 // Close closes the no-op closer. 74 func (c *NoopCloser) Close() { c.Calls++ }