From ced7238a6597039fb23f36f372bd1cf33d60d4a6 Mon Sep 17 00:00:00 2001
From: Michael Vogt <mvo@ubuntu.com>
Date: Thu, 25 Apr 2019 17:23:42 +0200
Subject: [PATCH] net: set DNSError.IsTemorary from addrinfoErrno errors

DNSErrors that are created via addrinfoErrno(...) currently do not
have the "IsTemporary" set. However the addrinfoErrno type itself
has the Temporary() property.

This PR sets DNSError.IsTemporary to the addrinfoErrno.Temporary
value. This is useful to e.g. detect if a DNSError is of type
EAI_AGAIN (which is currently not possible AFAICT).
---
 src/net/cgo_unix.go | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/net/cgo_unix.go b/src/net/cgo_unix.go
index 2baab5f1933..69c99fe7dbb 100644
--- a/src/net/cgo_unix.go
+++ b/src/net/cgo_unix.go
@@ -106,6 +106,7 @@ func cgoLookupServicePort(hints *C.struct_addrinfo, network, service string) (po
 	var res *C.struct_addrinfo
 	gerrno, err := C.getaddrinfo(nil, (*C.char)(unsafe.Pointer(&cservice[0])), hints, &res)
 	if gerrno != 0 {
+		isTemporary := false
 		switch gerrno {
 		case C.EAI_SYSTEM:
 			if err == nil { // see golang.org/issue/6232
@@ -113,8 +114,9 @@ func cgoLookupServicePort(hints *C.struct_addrinfo, network, service string) (po
 			}
 		default:
 			err = addrinfoErrno(gerrno)
+			isTemporary = addrinfoErrno(gerrno).Temporary()
 		}
-		return 0, &DNSError{Err: err.Error(), Name: network + "/" + service}
+		return 0, &DNSError{Err: err.Error(), Name: network + "/" + service, IsTemporary: isTemporary}
 	}
 	defer C.freeaddrinfo(res)
 
@@ -159,6 +161,7 @@ func cgoLookupIPCNAME(network, name string) (addrs []IPAddr, cname string, err e
 	gerrno, err := C.getaddrinfo((*C.char)(unsafe.Pointer(&h[0])), nil, &hints, &res)
 	if gerrno != 0 {
 		isErrorNoSuchHost := false
+		isTemporary := false
 		switch gerrno {
 		case C.EAI_SYSTEM:
 			if err == nil {
@@ -176,9 +179,10 @@ func cgoLookupIPCNAME(network, name string) (addrs []IPAddr, cname string, err e
 			isErrorNoSuchHost = true
 		default:
 			err = addrinfoErrno(gerrno)
+			isTemporary = addrinfoErrno(gerrno).Temporary()
 		}
 
-		return nil, "", &DNSError{Err: err.Error(), Name: name, IsNotFound: isErrorNoSuchHost}
+		return nil, "", &DNSError{Err: err.Error(), Name: name, IsNotFound: isErrorNoSuchHost, IsTemporary: isTemporary}
 	}
 	defer C.freeaddrinfo(res)
 
@@ -299,6 +303,7 @@ func cgoLookupAddrPTR(addr string, sa *C.struct_sockaddr, salen C.socklen_t) (na
 		}
 	}
 	if gerrno != 0 {
+		isTemporary := false
 		switch gerrno {
 		case C.EAI_SYSTEM:
 			if err == nil { // see golang.org/issue/6232
@@ -306,8 +311,9 @@ func cgoLookupAddrPTR(addr string, sa *C.struct_sockaddr, salen C.socklen_t) (na
 			}
 		default:
 			err = addrinfoErrno(gerrno)
+			isTemporary = addrinfoErrno(gerrno).Temporary()
 		}
-		return nil, &DNSError{Err: err.Error(), Name: addr}
+		return nil, &DNSError{Err: err.Error(), Name: addr, IsTemporary: isTemporary}
 	}
 	for i := 0; i < len(b); i++ {
 		if b[i] == 0 {