net: change SetTimeout to SetDeadline
Previously, a timeout (in int64 nanoseconds) applied to a granularity
even smaller than one operation: a 100 byte read with a 1 second timeout
could take 100 seconds, if the bytes all arrived on the network 1 second
apart. This was confusing.
Rather than making the timeout granularity be per-Read/Write,
this CL makes callers set an absolute deadline (in time.Time)
after which operations will fail. This makes it possible to
set deadlines at higher levels, without knowing exactly how
many read/write operations will happen in e.g. reading an HTTP
request.
Fixes #2723
R=r, rsc, dave
CC=golang-dev
https://golang.org/cl/5555048
diff --git a/src/pkg/net/net.go b/src/pkg/net/net.go
index b236dfd..7db7dfd 100644
--- a/src/pkg/net/net.go
+++ b/src/pkg/net/net.go
@@ -9,7 +9,10 @@
// TODO(rsc):
// support for raw ethernet sockets
-import "errors"
+import (
+ "errors"
+ "time"
+)
// Addr represents a network end point address.
type Addr interface {
@@ -38,21 +41,23 @@
// RemoteAddr returns the remote network address.
RemoteAddr() Addr
- // SetTimeout sets the read and write deadlines associated
+ // SetDeadline sets the read and write deadlines associated
// with the connection.
- SetTimeout(nsec int64) error
+ SetDeadline(t time.Time) error
- // SetReadTimeout sets the time (in nanoseconds) that
- // Read will wait for data before returning an error with Timeout() == true.
- // Setting nsec == 0 (the default) disables the deadline.
- SetReadTimeout(nsec int64) error
+ // SetReadDeadline sets the deadline for all Read calls to return.
+ // If the deadline is reached, Read will fail with a timeout
+ // (see type Error) instead of blocking.
+ // A zero value for t means Read will not time out.
+ SetReadDeadline(t time.Time) error
- // SetWriteTimeout sets the time (in nanoseconds) that
- // Write will wait to send its data before returning an error with Timeout() == true.
- // Setting nsec == 0 (the default) disables the deadline.
+ // SetWriteDeadline sets the deadline for all Write calls to return.
+ // If the deadline is reached, Write will fail with a timeout
+ // (see type Error) instead of blocking.
+ // A zero value for t means Write will not time out.
// Even if write times out, it may return n > 0, indicating that
// some of the data was successfully written.
- SetWriteTimeout(nsec int64) error
+ SetWriteDeadline(t time.Time) error
}
// An Error represents a network error.
@@ -70,13 +75,13 @@
// was on the packet.
// ReadFrom can be made to time out and return
// an error with Timeout() == true after a fixed time limit;
- // see SetTimeout and SetReadTimeout.
+ // see SetDeadline and SetReadDeadline.
ReadFrom(b []byte) (n int, addr Addr, err error)
// WriteTo writes a packet with payload b to addr.
// WriteTo can be made to time out and return
// an error with Timeout() == true after a fixed time limit;
- // see SetTimeout and SetWriteTimeout.
+ // see SetDeadline and SetWriteDeadline.
// On packet-oriented connections, write timeouts are rare.
WriteTo(b []byte, addr Addr) (n int, err error)
@@ -86,21 +91,23 @@
// LocalAddr returns the local network address.
LocalAddr() Addr
- // SetTimeout sets the read and write deadlines associated
+ // SetDeadline sets the read and write deadlines associated
// with the connection.
- SetTimeout(nsec int64) error
+ SetDeadline(t time.Time) error
- // SetReadTimeout sets the time (in nanoseconds) that
- // Read will wait for data before returning an error with Timeout() == true.
- // Setting nsec == 0 (the default) disables the deadline.
- SetReadTimeout(nsec int64) error
+ // SetReadDeadline sets the deadline for all Read calls to return.
+ // If the deadline is reached, Read will fail with a timeout
+ // (see type Error) instead of blocking.
+ // A zero value for t means Read will not time out.
+ SetReadDeadline(t time.Time) error
- // SetWriteTimeout sets the time (in nanoseconds) that
- // Write will wait to send its data before returning an error with Timeout() == true.
- // Setting nsec == 0 (the default) disables the deadline.
+ // SetWriteDeadline sets the deadline for all Write calls to return.
+ // If the deadline is reached, Write will fail with a timeout
+ // (see type Error) instead of blocking.
+ // A zero value for t means Write will not time out.
// Even if write times out, it may return n > 0, indicating that
// some of the data was successfully written.
- SetWriteTimeout(nsec int64) error
+ SetWriteDeadline(t time.Time) error
}
// A Listener is a generic network listener for stream-oriented protocols.
