From 917f78ce4ef2a4156d0291c36047689de1764c3f Mon Sep 17 00:00:00 2001 From: aimuz Date: Fri, 17 Nov 2023 16:44:12 +0800 Subject: [PATCH] net/netip: optimize parseIPv4 and refactor IPv6 embedded IPv4 parsing MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This change refactors the parseIPv4 function to extract a new helper function, parseIPv4Fields, which is now used by both parseIPv4 and parseIPv6 functions. The extraction of this logic into a separate helper function removes code duplication and improves the performance of parsing IPv6 addresses that contain an embedded IPv4 address. Additionally, the error handling within the IP address parsing logic has been streamlined to provide clearer messages when encountering incorrect formats or values in IPv4 fields. Benchmark: benchstat old.out new.out goos: darwin goarch: amd64 pkg: net/netip cpu: Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz │ old.out │ new.out │ │ sec/op │ sec/op vs base │ ParseAddr/v4-12 22.23n ± 2% 21.86n ± 2% ~ (p=0.127 n=10) ParseAddr/v6-12 69.67n ± 7% 70.31n ± 1% ~ (p=0.128 n=10) ParseAddr/v6_ellipsis-12 48.22n ± 17% 48.58n ± 1% ~ (p=0.739 n=10) ParseAddr/v6_v4-12 60.73n ± 36% 51.54n ± 1% -15.14% (p=0.000 n=10) ParseAddr/v6_zone-12 102.50n ± 22% 93.50n ± 0% -8.79% (p=0.000 n=10) ParseAddrPort/v4-12 38.07n ± 1% 36.84n ± 2% -3.22% (p=0.000 n=10) ParseAddrPort/v6-12 84.61n ± 1% 87.21n ± 1% +3.07% (p=0.000 n=10) ParseAddrPort/v6_ellipsis-12 69.65n ± 8% 64.56n ± 2% -7.31% (p=0.023 n=10) ParseAddrPort/v6_v4-12 71.88n ± 1% 70.61n ± 1% -1.76% (p=0.000 n=10) ParseAddrPort/v6_zone-12 119.0n ± 2% 118.0n ± 2% ~ (p=0.108 n=10) geomean 62.38n 60.17n -3.54% │ old.out │ new.out │ │ B/op │ B/op vs base │ ParseAddr/v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6_ellipsis-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6_v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6_zone-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6_ellipsis-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6_v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6_zone-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ geomean ² +0.00% ² ¹ all samples are equal ² summaries must be >0 to compute geomean │ old.out │ new.out │ │ allocs/op │ allocs/op vs base │ ParseAddr/v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6_ellipsis-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6_v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddr/v6_zone-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6_ellipsis-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6_v4-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ ParseAddrPort/v6_zone-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ geomean ² +0.00% ² ¹ all samples are equal ² summaries must be >0 to compute geomean --- src/net/netip/netip.go | 45 +++++++++++++++++++++---------------- src/net/netip/netip_test.go | 7 +++++- 2 files changed, 32 insertions(+), 20 deletions(-) diff --git a/src/net/netip/netip.go b/src/net/netip/netip.go index 46f466c076..3bda4ecc0f 100644 --- a/src/net/netip/netip.go +++ b/src/net/netip/netip.go @@ -152,44 +152,53 @@ func (err parseAddrError) Error() string { return "ParseAddr(" + q(err.in) + "): " + err.msg } -// parseIPv4 parses s as an IPv4 address (in form "192.168.0.1"). -func parseIPv4(s string) (ip Addr, err error) { - var fields [4]uint8 +func parseIPv4Fields(in string, off, end int, fields []uint8) error { var val, pos int var digLen int // number of digits in current octet + s := in[off:end] for i := 0; i < len(s); i++ { if s[i] >= '0' && s[i] <= '9' { if digLen == 1 && val == 0 { - return Addr{}, parseAddrError{in: s, msg: "IPv4 field has octet with leading zero"} + return parseAddrError{in: in, msg: "IPv4 field has octet with leading zero"} } val = val*10 + int(s[i]) - '0' digLen++ if val > 255 { - return Addr{}, parseAddrError{in: s, msg: "IPv4 field has value >255"} + return parseAddrError{in: in, msg: "IPv4 field has value >255"} } } else if s[i] == '.' { // .1.2.3 // 1.2.3. // 1..2.3 if i == 0 || i == len(s)-1 || s[i-1] == '.' { - return Addr{}, parseAddrError{in: s, msg: "IPv4 field must have at least one digit", at: s[i:]} + return parseAddrError{in: in, msg: "IPv4 field must have at least one digit", at: s[i:]} } // 1.2.3.4.5 if pos == 3 { - return Addr{}, parseAddrError{in: s, msg: "IPv4 address too long"} + return parseAddrError{in: in, msg: "IPv4 address too long"} } fields[pos] = uint8(val) pos++ val = 0 digLen = 0 } else { - return Addr{}, parseAddrError{in: s, msg: "unexpected character", at: s[i:]} + return parseAddrError{in: in, msg: "unexpected character", at: s[i:]} } } if pos < 3 { - return Addr{}, parseAddrError{in: s, msg: "IPv4 address too short"} + return parseAddrError{in: in, msg: "IPv4 address too short"} } fields[3] = uint8(val) + return nil +} + +// parseIPv4 parses s as an IPv4 address (in form "192.168.0.1"). +func parseIPv4(s string) (ip Addr, err error) { + var fields [4]uint8 + err = parseIPv4Fields(s, 0, len(s), fields[:]) + if err != nil { + return Addr{}, err + } return AddrFrom4(fields), nil } @@ -262,17 +271,15 @@ func parseIPv6(in string) (Addr, error) { // Not enough room. return Addr{}, parseAddrError{in: in, msg: "too many hex fields to fit an embedded IPv4 at the end of the address", at: s} } - // TODO: could make this a bit faster by having a helper - // that parses to a [4]byte, and have both parseIPv4 and - // parseIPv6 use it. - ip4, err := parseIPv4(s) - if err != nil { - return Addr{}, parseAddrError{in: in, msg: err.Error(), at: s} + + end := len(in) + if len(zone) > 0 { + end -= len(zone) + 1 + } + err := parseIPv4Fields(in, end-len(s), end, ip[i:i+4]) + if err != nil { + return Addr{}, err } - ip[i] = ip4.v4(0) - ip[i+1] = ip4.v4(1) - ip[i+2] = ip4.v4(2) - ip[i+3] = ip4.v4(3) s = "" i += 4 break diff --git a/src/net/netip/netip_test.go b/src/net/netip/netip_test.go index 36e57ce171..a3219886f3 100644 --- a/src/net/netip/netip_test.go +++ b/src/net/netip/netip_test.go @@ -60,7 +60,12 @@ func TestParseAddr(t *testing.T) { // 4-in-6 with octet with leading zero { in: "::ffff:1.2.03.4", - wantErr: `ParseAddr("::ffff:1.2.03.4"): ParseAddr("1.2.03.4"): IPv4 field has octet with leading zero (at "1.2.03.4")`, + wantErr: `ParseAddr("::ffff:1.2.03.4"): IPv4 field has octet with leading zero`, + }, + // 4-in-6 with octet with unexpected character + { + in: "::ffff:1.2.3.z", + wantErr: `ParseAddr("::ffff:1.2.3.z"): unexpected character (at "z")`, }, // Basic zero IPv6 address. {