Artifact [ec0e54e7cc]

Artifact ec0e54e7cc0cfa42abbb3aafff2e462b1b00e5a3953e715525aba542c94a4611:

• File internal/sync/version.go — part of check-in [6963b0a9dc] at 2026-10-12 23:10:13 on branch main — fix(sync): exchange server-version and gate SHA3 content by peer release (#303) (#358)

  fossil's page_xfer answers a client-version that carries DATE and TIME with pragma server-version, and both sides record the peer's release; send_file, send_compressed_file and send_unversioned_file then append "error Fossil version 2.0 or later required." in place of SHA3-named content for a peer older than 2.0, with a server treating a client that announced no release as one (sections 7.6, 9.1). The server sent no server-version and neither side kept or gated on the peer's release.

  The server gates gimme, clone and uvgimme; the client gates its answer to a gimme. Because a server-version from a current release turns fossil's client to logging in through the x-f-l-c cookie (section 6.5), the HTTP server now reads that cookie: xfer.DecodeRequest puts its login card first with the nonce bound to the whole body, as page_xfer does. Without it a real fossil client's later rounds arrived as nobody. That moves sync.6.5.server-cookie-login, marked for #304, here. (user: [email protected], size: 1914) [annotate] [blame] [check-ins using]

package sync

import (
	"strconv"

	"github.com/danmestas/go-libfossil/internal/xfer"
)

// The release this library announces in pragma client-version and
// server-version (§9.1): the fossil release whose protocol it speaks, and
// that release's check-in date and time.
const (
	releaseVersion = 22800
	releaseDate    = "20260315"
	releaseTime    = "120000"
)

// sha3Version is the first fossil release that accepts SHA3 artifact names.
// Content named by SHA3 is withheld from a peer older than this (§7.6).
const sha3Version = 20000

// sha1NameLen is the length of a SHA1 artifact name; any longer name is SHA3.
const sha1NameLen = 40

// versionPragma is the pragma that announces this library's release: name is
// "client-version" or "server-version".
func versionPragma(name string) *xfer.PragmaCard {
	return &xfer.PragmaCard{
		Name:   name,
		Values: []string{strconv.Itoa(releaseVersion), releaseDate, releaseTime},
	}
}

// peerVersion reads the VERSION of a client-version or server-version pragma
// as fossil's atoi does: leading digits, and 0 when there are none.
func peerVersion(c *xfer.PragmaCard) int {
	if len(c.Values) == 0 {
		panic("sync.peerVersion: pragma has no VERSION")
	}
	v := c.Values[0]
	n := 0
	for n < len(v) && v[n] >= '0' && v[n] <= '9' {
		n++
	}
	version, err := strconv.Atoi(v[:n])
	if err != nil {
		return 0
	}
	return version
}

// sha3Barred reports whether content named name is withheld from a peer of
// the given release: a SHA3 name, to a peer older than SHA3 support (§7.6).
func sha3Barred(name string, version int) bool {
	return len(name) > sha1NameLen && version < sha3Version
}

// sha3Refusal is the error card that takes the place of SHA3 content withheld
// from an older peer, worded as fossil's xfer_cannot_send_sha3_error words it.
func sha3Refusal() *xfer.ErrorCard {
	return &xfer.ErrorCard{Message: "Fossil version 2.0 or later required."}
}