github.com/murrekatt/go-ethereum@v1.5.8-0.20170123175102-fc52f2c007fb/mobile/context.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum 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 go-ethereum 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 go-ethereum 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  	"time"
    24  
    25  	"golang.org/x/net/context"
    26  )
    27  
    28  // Context carries a deadline, a cancelation signal, and other values across API
    29  // boundaries.
    30  type Context struct {
    31  	context context.Context
    32  	cancel  context.CancelFunc
    33  }
    34  
    35  // NewContext returns a non-nil, empty Context. It is never canceled, has no
    36  // values, and has no deadline. It is typically used by the main function,
    37  // initialization, and tests, and as the top-level Context for incoming requests.
    38  func NewContext() *Context {
    39  	return &Context{
    40  		context: context.Background(),
    41  	}
    42  }
    43  
    44  // WithCancel returns a copy of the original context with cancellation mechanism
    45  // included.
    46  //
    47  // Canceling this context releases resources associated with it, so code should
    48  // call cancel as soon as the operations running in this Context complete.
    49  func (c *Context) WithCancel() *Context {
    50  	child, cancel := context.WithCancel(c.context)
    51  	return &Context{
    52  		context: child,
    53  		cancel:  cancel,
    54  	}
    55  }
    56  
    57  // WithDeadline returns a copy of the original context with the deadline adjusted
    58  // to be no later than the specified time.
    59  //
    60  // Canceling this context releases resources associated with it, so code should
    61  // call cancel as soon as the operations running in this Context complete.
    62  func (c *Context) WithDeadline(sec int64, nsec int64) *Context {
    63  	child, cancel := context.WithDeadline(c.context, time.Unix(sec, nsec))
    64  	return &Context{
    65  		context: child,
    66  		cancel:  cancel,
    67  	}
    68  }
    69  
    70  // WithTimeout returns a copy of the original context with the deadline adjusted
    71  // to be no later than now + the duration specified.
    72  //
    73  // Canceling this context releases resources associated with it, so code should
    74  // call cancel as soon as the operations running in this Context complete.
    75  func (c *Context) WithTimeout(nsec int64) *Context {
    76  	child, cancel := context.WithTimeout(c.context, time.Duration(nsec))
    77  	return &Context{
    78  		context: child,
    79  		cancel:  cancel,
    80  	}
    81  }