github.com/SmartMeshFoundation/Spectrum@v0.0.0-20220621030607-452a266fee1e/mobile/context.go (about)

     1  // Copyright 2016 The Spectrum Authors
     2  // This file is part of the Spectrum library.
     3  //
     4  // The Spectrum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The Spectrum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the Spectrum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  // Contains all the wrappers from the golang.org/x/net/context package to support
    18  // client side context management on mobile platforms.
    19  
    20  package geth
    21  
    22  import (
    23  	"context"
    24  	"time"
    25  )
    26  
    27  // Context carries a deadline, a cancelation signal, and other values across API
    28  // boundaries.
    29  type Context struct {
    30  	context context.Context
    31  	cancel  context.CancelFunc
    32  }
    33  
    34  // NewContext returns a non-nil, empty Context. It is never canceled, has no
    35  // values, and has no deadline. It is typically used by the main function,
    36  // initialization, and tests, and as the top-level Context for incoming requests.
    37  func NewContext() *Context {
    38  	return &Context{
    39  		context: context.Background(),
    40  	}
    41  }
    42  
    43  // WithCancel returns a copy of the original context with cancellation mechanism
    44  // included.
    45  //
    46  // Canceling this context releases resources associated with it, so code should
    47  // call cancel as soon as the operations running in this Context complete.
    48  func (c *Context) WithCancel() *Context {
    49  	child, cancel := context.WithCancel(c.context)
    50  	return &Context{
    51  		context: child,
    52  		cancel:  cancel,
    53  	}
    54  }
    55  
    56  // WithDeadline returns a copy of the original context with the deadline adjusted
    57  // to be no later than the specified time.
    58  //
    59  // Canceling this context releases resources associated with it, so code should
    60  // call cancel as soon as the operations running in this Context complete.
    61  func (c *Context) WithDeadline(sec int64, nsec int64) *Context {
    62  	child, cancel := context.WithDeadline(c.context, time.Unix(sec, nsec))
    63  	return &Context{
    64  		context: child,
    65  		cancel:  cancel,
    66  	}
    67  }
    68  
    69  // WithTimeout returns a copy of the original context with the deadline adjusted
    70  // to be no later than now + the duration specified.
    71  //
    72  // Canceling this context releases resources associated with it, so code should
    73  // call cancel as soon as the operations running in this Context complete.
    74  func (c *Context) WithTimeout(nsec int64) *Context {
    75  	child, cancel := context.WithTimeout(c.context, time.Duration(nsec))
    76  	return &Context{
    77  		context: child,
    78  		cancel:  cancel,
    79  	}
    80  }