github.com/quic-go/quic-go@v0.44.0/sys_conn_helper_linux_test.go (about)

     1  //go:build linux
     2  
     3  package quic
     4  
     5  import (
     6  	"errors"
     7  	"net"
     8  	"os"
     9  
    10  	"golang.org/x/sys/unix"
    11  
    12  	. "github.com/onsi/ginkgo/v2"
    13  	. "github.com/onsi/gomega"
    14  )
    15  
    16  var (
    17  	errGSO          = &os.SyscallError{Err: unix.EIO}
    18  	errNotPermitted = &os.SyscallError{Syscall: "sendmsg", Err: unix.EPERM}
    19  )
    20  
    21  var _ = Describe("forcing a change of send and receive buffer sizes", func() {
    22  	It("forces a change of the receive buffer size", func() {
    23  		if os.Getuid() != 0 {
    24  			Skip("Must be root to force change the receive buffer size")
    25  		}
    26  
    27  		c, err := net.ListenPacket("udp", "127.0.0.1:0")
    28  		Expect(err).ToNot(HaveOccurred())
    29  		defer c.Close()
    30  		syscallConn, err := c.(*net.UDPConn).SyscallConn()
    31  		Expect(err).ToNot(HaveOccurred())
    32  
    33  		const small = 256 << 10 // 256 KB
    34  		Expect(forceSetReceiveBuffer(syscallConn, small)).To(Succeed())
    35  
    36  		size, err := inspectReadBuffer(syscallConn)
    37  		Expect(err).ToNot(HaveOccurred())
    38  		//  The kernel doubles this value (to allow space for bookkeeping overhead)
    39  		Expect(size).To(Equal(2 * small))
    40  
    41  		const large = 32 << 20 // 32 MB
    42  		Expect(forceSetReceiveBuffer(syscallConn, large)).To(Succeed())
    43  		size, err = inspectReadBuffer(syscallConn)
    44  		Expect(err).ToNot(HaveOccurred())
    45  		//  The kernel doubles this value (to allow space for bookkeeping overhead)
    46  		Expect(size).To(Equal(2 * large))
    47  	})
    48  
    49  	It("forces a change of the send buffer size", func() {
    50  		if os.Getuid() != 0 {
    51  			Skip("Must be root to force change the send buffer size")
    52  		}
    53  
    54  		c, err := net.ListenPacket("udp", "127.0.0.1:0")
    55  		Expect(err).ToNot(HaveOccurred())
    56  		defer c.Close()
    57  		syscallConn, err := c.(*net.UDPConn).SyscallConn()
    58  		Expect(err).ToNot(HaveOccurred())
    59  
    60  		const small = 256 << 10 // 256 KB
    61  		Expect(forceSetSendBuffer(syscallConn, small)).To(Succeed())
    62  
    63  		size, err := inspectWriteBuffer(syscallConn)
    64  		Expect(err).ToNot(HaveOccurred())
    65  		//  The kernel doubles this value (to allow space for bookkeeping overhead)
    66  		Expect(size).To(Equal(2 * small))
    67  
    68  		const large = 32 << 20 // 32 MB
    69  		Expect(forceSetSendBuffer(syscallConn, large)).To(Succeed())
    70  		size, err = inspectWriteBuffer(syscallConn)
    71  		Expect(err).ToNot(HaveOccurred())
    72  		//  The kernel doubles this value (to allow space for bookkeeping overhead)
    73  		Expect(size).To(Equal(2 * large))
    74  	})
    75  
    76  	It("detects GSO errors", func() {
    77  		Expect(isGSOError(errGSO)).To(BeTrue())
    78  		Expect(isGSOError(nil)).To(BeFalse())
    79  		Expect(isGSOError(errors.New("test"))).To(BeFalse())
    80  	})
    81  })