1501 lines
52 KiB
HTML
1501 lines
52 KiB
HTML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
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"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
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<head>
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<meta http-equiv="Content-Type" content="application/xhtml+xml; charset=UTF-8" />
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<meta name="generator" content="AsciiDoc 10.2.0" />
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<title>gitprotocol-pack(5)</title>
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<style type="text/css">
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/* Shared CSS for AsciiDoc xhtml11 and html5 backends */
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/* Default font. */
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body {
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font-family: Georgia,serif;
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}
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/* Title font. */
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h1, h2, h3, h4, h5, h6,
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div.title, caption.title,
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thead, p.table.header,
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#toctitle,
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#author, #revnumber, #revdate, #revremark,
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#footer {
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font-family: Arial,Helvetica,sans-serif;
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}
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body {
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margin: 1em 5% 1em 5%;
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}
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a {
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color: blue;
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text-decoration: underline;
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}
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a:visited {
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color: fuchsia;
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}
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em {
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font-style: italic;
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color: navy;
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}
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strong {
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font-weight: bold;
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color: #083194;
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}
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h1, h2, h3, h4, h5, h6 {
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color: #527bbd;
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margin-top: 1.2em;
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margin-bottom: 0.5em;
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line-height: 1.3;
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}
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h1, h2, h3 {
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border-bottom: 2px solid silver;
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}
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h2 {
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padding-top: 0.5em;
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}
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h3 {
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float: left;
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}
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h3 + * {
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clear: left;
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}
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h5 {
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font-size: 1.0em;
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}
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div.sectionbody {
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margin-left: 0;
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}
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hr {
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border: 1px solid silver;
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}
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p {
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margin-top: 0.5em;
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margin-bottom: 0.5em;
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}
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ul, ol, li > p {
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margin-top: 0;
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}
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ul > li { color: #aaa; }
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ul > li > * { color: black; }
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.monospaced, code, pre {
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font-family: "Courier New", Courier, monospace;
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font-size: inherit;
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color: navy;
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padding: 0;
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margin: 0;
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}
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pre {
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white-space: pre-wrap;
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}
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#author {
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color: #527bbd;
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font-weight: bold;
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font-size: 1.1em;
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}
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#email {
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}
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#revnumber, #revdate, #revremark {
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}
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#footer {
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font-size: small;
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border-top: 2px solid silver;
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padding-top: 0.5em;
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margin-top: 4.0em;
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}
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#footer-text {
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float: left;
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padding-bottom: 0.5em;
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}
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#footer-badges {
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float: right;
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padding-bottom: 0.5em;
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}
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#preamble {
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margin-top: 1.5em;
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margin-bottom: 1.5em;
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}
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div.imageblock, div.exampleblock, div.verseblock,
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div.quoteblock, div.literalblock, div.listingblock, div.sidebarblock,
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div.admonitionblock {
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margin-top: 1.0em;
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margin-bottom: 1.5em;
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}
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div.admonitionblock {
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margin-top: 2.0em;
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margin-bottom: 2.0em;
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margin-right: 10%;
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color: #606060;
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}
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div.content { /* Block element content. */
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padding: 0;
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}
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/* Block element titles. */
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div.title, caption.title {
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color: #527bbd;
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font-weight: bold;
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text-align: left;
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margin-top: 1.0em;
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margin-bottom: 0.5em;
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}
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div.title + * {
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margin-top: 0;
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}
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td div.title:first-child {
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margin-top: 0.0em;
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}
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div.content div.title:first-child {
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margin-top: 0.0em;
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}
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div.content + div.title {
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margin-top: 0.0em;
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}
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div.sidebarblock > div.content {
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background: #ffffee;
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border: 1px solid #dddddd;
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border-left: 4px solid #f0f0f0;
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padding: 0.5em;
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}
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div.listingblock > div.content {
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border: 1px solid #dddddd;
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border-left: 5px solid #f0f0f0;
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background: #f8f8f8;
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padding: 0.5em;
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}
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div.quoteblock, div.verseblock {
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padding-left: 1.0em;
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margin-left: 1.0em;
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margin-right: 10%;
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border-left: 5px solid #f0f0f0;
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color: #888;
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}
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div.quoteblock > div.attribution {
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padding-top: 0.5em;
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text-align: right;
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}
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div.verseblock > pre.content {
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font-family: inherit;
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font-size: inherit;
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}
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div.verseblock > div.attribution {
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padding-top: 0.75em;
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text-align: left;
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}
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/* DEPRECATED: Pre version 8.2.7 verse style literal block. */
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div.verseblock + div.attribution {
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text-align: left;
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}
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div.admonitionblock .icon {
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vertical-align: top;
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font-size: 1.1em;
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font-weight: bold;
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text-decoration: underline;
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color: #527bbd;
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padding-right: 0.5em;
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}
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div.admonitionblock td.content {
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padding-left: 0.5em;
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border-left: 3px solid #dddddd;
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}
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div.exampleblock > div.content {
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border-left: 3px solid #dddddd;
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padding-left: 0.5em;
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}
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div.imageblock div.content { padding-left: 0; }
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span.image img { border-style: none; vertical-align: text-bottom; }
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a.image:visited { color: white; }
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dl {
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margin-top: 0.8em;
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margin-bottom: 0.8em;
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}
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dt {
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margin-top: 0.5em;
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margin-bottom: 0;
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font-style: normal;
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color: navy;
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}
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dd > *:first-child {
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margin-top: 0.1em;
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}
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ul, ol {
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list-style-position: outside;
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}
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ol.arabic {
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list-style-type: decimal;
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}
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ol.loweralpha {
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list-style-type: lower-alpha;
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}
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ol.upperalpha {
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list-style-type: upper-alpha;
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}
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ol.lowerroman {
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list-style-type: lower-roman;
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}
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ol.upperroman {
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list-style-type: upper-roman;
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}
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div.compact ul, div.compact ol,
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div.compact p, div.compact p,
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div.compact div, div.compact div {
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margin-top: 0.1em;
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margin-bottom: 0.1em;
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}
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tfoot {
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font-weight: bold;
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}
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td > div.verse {
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white-space: pre;
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}
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div.hdlist {
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margin-top: 0.8em;
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margin-bottom: 0.8em;
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}
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div.hdlist tr {
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padding-bottom: 15px;
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}
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dt.hdlist1.strong, td.hdlist1.strong {
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font-weight: bold;
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}
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td.hdlist1 {
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vertical-align: top;
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font-style: normal;
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padding-right: 0.8em;
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color: navy;
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}
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td.hdlist2 {
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vertical-align: top;
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}
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div.hdlist.compact tr {
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margin: 0;
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padding-bottom: 0;
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}
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.comment {
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background: yellow;
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}
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.footnote, .footnoteref {
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font-size: 0.8em;
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}
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span.footnote, span.footnoteref {
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vertical-align: super;
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}
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#footnotes {
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margin: 20px 0 20px 0;
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padding: 7px 0 0 0;
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}
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#footnotes div.footnote {
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margin: 0 0 5px 0;
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}
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#footnotes hr {
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border: none;
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border-top: 1px solid silver;
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height: 1px;
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text-align: left;
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margin-left: 0;
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width: 20%;
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min-width: 100px;
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}
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div.colist td {
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padding-right: 0.5em;
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padding-bottom: 0.3em;
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vertical-align: top;
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}
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div.colist td img {
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margin-top: 0.3em;
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}
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@media print {
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#footer-badges { display: none; }
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}
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#toc {
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margin-bottom: 2.5em;
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}
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#toctitle {
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color: #527bbd;
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font-size: 1.1em;
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font-weight: bold;
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margin-top: 1.0em;
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margin-bottom: 0.1em;
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}
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div.toclevel0, div.toclevel1, div.toclevel2, div.toclevel3, div.toclevel4 {
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margin-top: 0;
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margin-bottom: 0;
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}
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div.toclevel2 {
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margin-left: 2em;
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font-size: 0.9em;
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}
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div.toclevel3 {
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margin-left: 4em;
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font-size: 0.9em;
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}
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div.toclevel4 {
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margin-left: 6em;
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font-size: 0.9em;
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}
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span.aqua { color: aqua; }
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span.black { color: black; }
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span.blue { color: blue; }
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span.fuchsia { color: fuchsia; }
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span.gray { color: gray; }
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span.green { color: green; }
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span.lime { color: lime; }
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span.maroon { color: maroon; }
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span.navy { color: navy; }
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span.olive { color: olive; }
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span.purple { color: purple; }
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span.red { color: red; }
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span.silver { color: silver; }
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span.teal { color: teal; }
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span.white { color: white; }
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span.yellow { color: yellow; }
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span.aqua-background { background: aqua; }
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span.black-background { background: black; }
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span.blue-background { background: blue; }
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span.fuchsia-background { background: fuchsia; }
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span.gray-background { background: gray; }
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span.green-background { background: green; }
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span.lime-background { background: lime; }
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span.maroon-background { background: maroon; }
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span.navy-background { background: navy; }
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span.olive-background { background: olive; }
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span.purple-background { background: purple; }
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span.red-background { background: red; }
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span.silver-background { background: silver; }
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span.teal-background { background: teal; }
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span.white-background { background: white; }
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span.yellow-background { background: yellow; }
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span.big { font-size: 2em; }
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span.small { font-size: 0.6em; }
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span.underline { text-decoration: underline; }
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span.overline { text-decoration: overline; }
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span.line-through { text-decoration: line-through; }
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div.unbreakable { page-break-inside: avoid; }
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/*
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* xhtml11 specific
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*
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* */
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div.tableblock {
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margin-top: 1.0em;
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margin-bottom: 1.5em;
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}
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div.tableblock > table {
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border: 3px solid #527bbd;
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}
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thead, p.table.header {
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font-weight: bold;
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color: #527bbd;
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}
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p.table {
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margin-top: 0;
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}
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/* Because the table frame attribute is overridden by CSS in most browsers. */
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div.tableblock > table[frame="void"] {
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border-style: none;
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}
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div.tableblock > table[frame="hsides"] {
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border-left-style: none;
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border-right-style: none;
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}
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div.tableblock > table[frame="vsides"] {
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border-top-style: none;
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border-bottom-style: none;
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}
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/*
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* html5 specific
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*
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* */
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table.tableblock {
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margin-top: 1.0em;
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margin-bottom: 1.5em;
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}
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thead, p.tableblock.header {
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font-weight: bold;
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color: #527bbd;
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}
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p.tableblock {
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margin-top: 0;
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}
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table.tableblock {
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border-width: 3px;
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border-spacing: 0px;
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border-style: solid;
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border-color: #527bbd;
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border-collapse: collapse;
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}
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th.tableblock, td.tableblock {
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border-width: 1px;
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padding: 4px;
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border-style: solid;
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border-color: #527bbd;
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}
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table.tableblock.frame-topbot {
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border-left-style: hidden;
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border-right-style: hidden;
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}
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table.tableblock.frame-sides {
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border-top-style: hidden;
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border-bottom-style: hidden;
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}
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table.tableblock.frame-none {
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border-style: hidden;
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}
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th.tableblock.halign-left, td.tableblock.halign-left {
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text-align: left;
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}
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th.tableblock.halign-center, td.tableblock.halign-center {
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text-align: center;
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}
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th.tableblock.halign-right, td.tableblock.halign-right {
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text-align: right;
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}
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th.tableblock.valign-top, td.tableblock.valign-top {
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vertical-align: top;
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}
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th.tableblock.valign-middle, td.tableblock.valign-middle {
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vertical-align: middle;
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}
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th.tableblock.valign-bottom, td.tableblock.valign-bottom {
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vertical-align: bottom;
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}
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|
|
|
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/*
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* manpage specific
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*
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* */
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|
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body.manpage h1 {
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padding-top: 0.5em;
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padding-bottom: 0.5em;
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border-top: 2px solid silver;
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border-bottom: 2px solid silver;
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}
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|
body.manpage h2 {
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border-style: none;
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}
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body.manpage div.sectionbody {
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margin-left: 3em;
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}
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@media print {
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body.manpage div#toc { display: none; }
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}
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|
|
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</style>
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<script type="text/javascript">
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/*<+'])');
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// Function that scans the DOM tree for header elements (the DOM2
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|
// nodeIterator API would be a better technique but not supported by all
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|
// browsers).
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|
var iterate = function (el) {
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|
for (var i = el.firstChild; i != null; i = i.nextSibling) {
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if (i.nodeType == 1 /* Node.ELEMENT_NODE */) {
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var mo = re.exec(i.tagName);
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if (mo && (i.getAttribute("class") || i.getAttribute("className")) != "float") {
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result[result.length] = new TocEntry(i, getText(i), mo[1]-1);
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}
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iterate(i);
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}
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}
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}
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iterate(el);
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return result;
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}
|
|
|
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var toc = document.getElementById("toc");
|
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if (!toc) {
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return;
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}
|
|
|
|
// Delete existing TOC entries in case we're reloading the TOC.
|
|
var tocEntriesToRemove = [];
|
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var i;
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for (i = 0; i < toc.childNodes.length; i++) {
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var entry = toc.childNodes[i];
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if (entry.nodeName.toLowerCase() == 'div'
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&& entry.getAttribute("class")
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&& entry.getAttribute("class").match(/^toclevel/))
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tocEntriesToRemove.push(entry);
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}
|
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for (i = 0; i < tocEntriesToRemove.length; i++) {
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toc.removeChild(tocEntriesToRemove[i]);
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}
|
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|
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// Rebuild TOC entries.
|
|
var entries = tocEntries(document.getElementById("content"), toclevels);
|
|
for (var i = 0; i < entries.length; ++i) {
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var entry = entries[i];
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|
if (entry.element.id == "")
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|
entry.element.id = "_toc_" + i;
|
|
var a = document.createElement("a");
|
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|
/*]]>*/
|
|
</script>
|
|
</head>
|
|
<body class="manpage">
|
|
<div id="header">
|
|
<h1>
|
|
gitprotocol-pack(5) Manual Page
|
|
</h1>
|
|
<h2>NAME</h2>
|
|
<div class="sectionbody">
|
|
<p>gitprotocol-pack -
|
|
How packs are transferred over-the-wire
|
|
</p>
|
|
</div>
|
|
</div>
|
|
<div id="content">
|
|
<div class="sect1">
|
|
<h2 id="_synopsis">SYNOPSIS</h2>
|
|
<div class="sectionbody">
|
|
<div class="verseblock">
|
|
<pre class="content"><over-the-wire-protocol></pre>
|
|
<div class="attribution">
|
|
</div></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_description">DESCRIPTION</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>Git supports transferring data in packfiles over the ssh://, git://, http:// and
|
|
file:// transports. There exist two sets of protocols, one for pushing
|
|
data from a client to a server and another for fetching data from a
|
|
server to a client. The three transports (ssh, git, file) use the same
|
|
protocol to transfer data. http is documented in <a href="gitprotocol-http.html">gitprotocol-http(5)</a>.</p></div>
|
|
<div class="paragraph"><p>The processes invoked in the canonical Git implementation are <em>upload-pack</em>
|
|
on the server side and <em>fetch-pack</em> on the client side for fetching data;
|
|
then <em>receive-pack</em> on the server and <em>send-pack</em> on the client for pushing
|
|
data. The protocol functions to have a server tell a client what is
|
|
currently on the server, then for the two to negotiate the smallest amount
|
|
of data to send in order to fully update one or the other.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_pkt_line_format">pkt-line Format</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>The descriptions below build on the pkt-line format described in
|
|
<a href="gitprotocol-common.html">gitprotocol-common(5)</a>. When the grammar indicates <code>PKT-LINE</code>(<code>...</code>), unless
|
|
otherwise noted the usual pkt-line LF rules apply: the sender SHOULD
|
|
include a LF, but the receiver MUST NOT complain if it is not present.</p></div>
|
|
<div class="paragraph"><p>An error packet is a special pkt-line that contains an error string.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> error-line = PKT-LINE("ERR" SP explanation-text)</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>Throughout the protocol, where <code>PKT-LINE</code>(<code>...</code>) is expected, an error packet MAY
|
|
be sent. Once this packet is sent by a client or a server, the data transfer
|
|
process defined in this protocol is terminated.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_transports">Transports</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>There are three transports over which the packfile protocol is
|
|
initiated. The Git transport is a simple, unauthenticated server that
|
|
takes the command (almost always <em>upload-pack</em>, though Git
|
|
servers can be configured to be globally writable, in which <em>receive-
|
|
pack</em> initiation is also allowed) with which the client wishes to
|
|
communicate and executes it and connects it to the requesting
|
|
process.</p></div>
|
|
<div class="paragraph"><p>In the SSH transport, the client just runs the <em>upload-pack</em>
|
|
or <em>receive-pack</em> process on the server over the SSH protocol and then
|
|
communicates with that invoked process over the SSH connection.</p></div>
|
|
<div class="paragraph"><p>The file:// transport runs the <em>upload-pack</em> or <em>receive-pack</em>
|
|
process locally and communicates with it over a pipe.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_extra_parameters">Extra Parameters</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>The protocol provides a mechanism in which clients can send additional
|
|
information in its first message to the server. These are called "Extra
|
|
Parameters", and are supported by the Git, SSH, and HTTP protocols.</p></div>
|
|
<div class="paragraph"><p>Each Extra Parameter takes the form of <em><key></em><code>=</code><em><value></em> or <em><key></em>.</p></div>
|
|
<div class="paragraph"><p>Servers that receive any such Extra Parameters MUST ignore all
|
|
unrecognized keys. Currently, the only Extra Parameter recognized is
|
|
"version" with a value of <em>1</em> or <em>2</em>. See <a href="gitprotocol-v2.html">gitprotocol-v2(5)</a> for more
|
|
information on protocol version 2.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_git_transport">Git Transport</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>The Git transport starts off by sending the command and repository
|
|
on the wire using the pkt-line format, followed by a NUL byte and a
|
|
hostname parameter, terminated by a NUL byte.</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code>0033git-upload-pack /project.git\0host=myserver.com\0</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>The transport may send Extra Parameters by adding an additional NUL
|
|
byte, and then adding one or more NUL-terminated strings:</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code>003egit-upload-pack /project.git\0host=myserver.com\0\0version=1\0</code></pre>
|
|
</div></div>
|
|
<div class="openblock">
|
|
<div class="content">
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code>git-proto-request = request-command SP pathname NUL
|
|
[ host-parameter NUL ] [ NUL extra-parameters ]
|
|
request-command = "git-upload-pack" / "git-receive-pack" /
|
|
"git-upload-archive" ; case sensitive
|
|
pathname = *( %x01-ff ) ; exclude NUL
|
|
host-parameter = "host=" hostname [ ":" port ]
|
|
extra-parameters = 1*extra-parameter
|
|
extra-parameter = 1*( %x01-ff ) NUL</code></pre>
|
|
</div></div>
|
|
</div></div>
|
|
<div class="paragraph"><p>host-parameter is used for the
|
|
git-daemon name based virtual hosting. See --interpolated-path
|
|
option to git daemon, with the %H/%CH format characters.</p></div>
|
|
<div class="paragraph"><p>Basically what the Git client is doing to connect to an <em>upload-pack</em>
|
|
process on the server side over the Git protocol is this:</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code>$ echo -e -n \
|
|
"003agit-upload-pack /schacon/gitbook.git\0host=example.com\0" |
|
|
nc -v example.com 9418</code></pre>
|
|
</div></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_ssh_transport">SSH Transport</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>Initiating the upload-pack or receive-pack processes over SSH is
|
|
executing the binary on the server via SSH remote execution.
|
|
It is basically equivalent to running this:</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code>$ ssh git.example.com "git-upload-pack '/project.git'"</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>For a server to support Git pushing and pulling for a given user over
|
|
SSH, that user needs to be able to execute one or both of those
|
|
commands via the SSH shell that they are provided on login. On some
|
|
systems, that shell access is limited to only being able to run those
|
|
two commands, or even just one of them.</p></div>
|
|
<div class="paragraph"><p>In an ssh:// format URI, it’s absolute in the URI, so the <em>/</em> after
|
|
the host name (or port number) is sent as an argument, which is then
|
|
read by the remote git-upload-pack exactly as is, so it’s effectively
|
|
an absolute path in the remote filesystem.</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code> git clone ssh://user@example.com/project.git
|
|
|
|
|
v
|
|
ssh user@example.com "git-upload-pack '/project.git'"</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>In a "user@host:path" format URI, it’s relative to the user’s home
|
|
directory, because the Git client will run:</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code> git clone user@example.com:project.git
|
|
|
|
|
v
|
|
ssh user@example.com "git-upload-pack 'project.git'"</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>The exception is if a <em>~</em> is used, in which case
|
|
we execute it without the leading <em>/</em>.</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code> ssh://user@example.com/~alice/project.git,
|
|
|
|
|
v
|
|
ssh user@example.com "git-upload-pack '~alice/project.git'"</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>Depending on the value of the <code>protocol.version</code> configuration variable,
|
|
Git may attempt to send Extra Parameters as a colon-separated string in
|
|
the GIT_PROTOCOL environment variable. This is done only if
|
|
the <code>ssh.variant</code> configuration variable indicates that the ssh command
|
|
supports passing environment variables as an argument.</p></div>
|
|
<div class="paragraph"><p>A few things to remember here:</p></div>
|
|
<div class="ulist"><ul>
|
|
<li>
|
|
<p>
|
|
The "command name" is spelled with dash (e.g. git-upload-pack), but
|
|
this can be overridden by the client;
|
|
</p>
|
|
</li>
|
|
<li>
|
|
<p>
|
|
The repository path is always quoted with single quotes.
|
|
</p>
|
|
</li>
|
|
</ul></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_fetching_data_from_a_server">Fetching Data From a Server</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>When one Git repository wants to get data that a second repository
|
|
has, the first can <em>fetch</em> from the second. This operation determines
|
|
what data the server has that the client does not then streams that
|
|
data down to the client in packfile format.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_reference_discovery">Reference Discovery</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>When the client initially connects the server will immediately respond
|
|
with a version number (if "version=1" is sent as an Extra Parameter),
|
|
and a listing of each reference it has (all branches and tags) along
|
|
with the object name that each reference currently points to.</p></div>
|
|
<div class="literalblock">
|
|
<div class="content">
|
|
<pre><code>$ echo -e -n "0045git-upload-pack /schacon/gitbook.git\0host=example.com\0\0version=1\0" |
|
|
nc -v example.com 9418
|
|
000eversion 1
|
|
00887217a7c7e582c46cec22a130adf4b9d7d950fba0 HEAD\0multi_ack thin-pack
|
|
side-band side-band-64k ofs-delta shallow no-progress include-tag
|
|
00441d3fcd5ced445d1abc402225c0b8a1299641f497 refs/heads/integration
|
|
003f7217a7c7e582c46cec22a130adf4b9d7d950fba0 refs/heads/master
|
|
003cb88d2441cac0977faf98efc80305012112238d9d refs/tags/v0.9
|
|
003c525128480b96c89e6418b1e40909bf6c5b2d580f refs/tags/v1.0
|
|
003fe92df48743b7bc7d26bcaabfddde0a1e20cae47c refs/tags/v1.0^{}
|
|
0000</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>The returned response is a pkt-line stream describing each ref and
|
|
its current value. The stream MUST be sorted by name according to
|
|
the C locale ordering.</p></div>
|
|
<div class="paragraph"><p>If HEAD is a valid ref, HEAD MUST appear as the first advertised
|
|
ref. If HEAD is not a valid ref, HEAD MUST NOT appear in the
|
|
advertisement list at all, but other refs may still appear.</p></div>
|
|
<div class="paragraph"><p>The stream MUST include capability declarations behind a NUL on the
|
|
first ref. The peeled value of a ref (that is "ref^{}") MUST be
|
|
immediately after the ref itself, if presented. A conforming server
|
|
MUST peel the ref if it’s an annotated tag.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> advertised-refs = *1("version 1")
|
|
(no-refs / list-of-refs)
|
|
*shallow
|
|
flush-pkt
|
|
|
|
no-refs = PKT-LINE(zero-id SP "capabilities^{}"
|
|
NUL capability-list)
|
|
|
|
list-of-refs = first-ref *other-ref
|
|
first-ref = PKT-LINE(obj-id SP refname
|
|
NUL capability-list)
|
|
|
|
other-ref = PKT-LINE(other-tip / other-peeled)
|
|
other-tip = obj-id SP refname
|
|
other-peeled = obj-id SP refname "^{}"
|
|
|
|
shallow = PKT-LINE("shallow" SP obj-id)
|
|
|
|
capability-list = capability *(SP capability)
|
|
capability = 1*(LC_ALPHA / DIGIT / "-" / "_")
|
|
LC_ALPHA = %x61-7A</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>Server and client MUST use lowercase for obj-id, both MUST treat obj-id
|
|
as case-insensitive.</p></div>
|
|
<div class="paragraph"><p>See protocol-capabilities.txt for a list of allowed server capabilities
|
|
and descriptions.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_packfile_negotiation">Packfile Negotiation</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>After reference and capabilities discovery, the client can decide to
|
|
terminate the connection by sending a flush-pkt, telling the server it can
|
|
now gracefully terminate, and disconnect, when it does not need any pack
|
|
data. This can happen with the ls-remote command, and also can happen when
|
|
the client already is up to date.</p></div>
|
|
<div class="paragraph"><p>Otherwise, it enters the negotiation phase, where the client and
|
|
server determine what the minimal packfile necessary for transport is,
|
|
by telling the server what objects it wants, its shallow objects
|
|
(if any), and the maximum commit depth it wants (if any). The client
|
|
will also send a list of the capabilities it wants to be in effect,
|
|
out of what the server said it could do with the first <em>want</em> line.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> upload-request = want-list
|
|
*shallow-line
|
|
*1depth-request
|
|
[filter-request]
|
|
flush-pkt
|
|
|
|
want-list = first-want
|
|
*additional-want
|
|
|
|
shallow-line = PKT-LINE("shallow" SP obj-id)
|
|
|
|
depth-request = PKT-LINE("deepen" SP depth) /
|
|
PKT-LINE("deepen-since" SP timestamp) /
|
|
PKT-LINE("deepen-not" SP ref)
|
|
|
|
first-want = PKT-LINE("want" SP obj-id SP capability-list)
|
|
additional-want = PKT-LINE("want" SP obj-id)
|
|
|
|
depth = 1*DIGIT
|
|
|
|
filter-request = PKT-LINE("filter" SP filter-spec)</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>Clients MUST send all the obj-ids it wants from the reference
|
|
discovery phase as <em>want</em> lines. Clients MUST send at least one
|
|
<em>want</em> command in the request body. Clients MUST NOT mention an
|
|
obj-id in a <em>want</em> command which did not appear in the response
|
|
obtained through ref discovery.</p></div>
|
|
<div class="paragraph"><p>The client MUST write all obj-ids which it only has shallow copies
|
|
of (meaning that it does not have the parents of a commit) as
|
|
<em>shallow</em> lines so that the server is aware of the limitations of
|
|
the client’s history.</p></div>
|
|
<div class="paragraph"><p>The client now sends the maximum commit history depth it wants for
|
|
this transaction, which is the number of commits it wants from the
|
|
tip of the history, if any, as a <em>deepen</em> line. A depth of 0 is the
|
|
same as not making a depth request. The client does not want to receive
|
|
any commits beyond this depth, nor does it want objects needed only to
|
|
complete those commits. Commits whose parents are not received as a
|
|
result are defined as shallow and marked as such in the server. This
|
|
information is sent back to the client in the next step.</p></div>
|
|
<div class="paragraph"><p>The client can optionally request that pack-objects omit various
|
|
objects from the packfile using one of several filtering techniques.
|
|
These are intended for use with partial clone and partial fetch
|
|
operations. An object that does not meet a filter-spec value is
|
|
omitted unless explicitly requested in a <em>want</em> line. See <code>rev-list</code>
|
|
for possible filter-spec values.</p></div>
|
|
<div class="paragraph"><p>Once all the <em>want’s and 'shallow’s (and optional 'deepen</em>) are
|
|
transferred, clients MUST send a flush-pkt, to tell the server side
|
|
that it is done sending the list.</p></div>
|
|
<div class="paragraph"><p>Otherwise, if the client sent a positive depth request, the server
|
|
will determine which commits will and will not be shallow and
|
|
send this information to the client. If the client did not request
|
|
a positive depth, this step is skipped.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> shallow-update = *shallow-line
|
|
*unshallow-line
|
|
flush-pkt
|
|
|
|
shallow-line = PKT-LINE("shallow" SP obj-id)
|
|
|
|
unshallow-line = PKT-LINE("unshallow" SP obj-id)</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>If the client has requested a positive depth, the server will compute
|
|
the set of commits which are no deeper than the desired depth. The set
|
|
of commits starts at the client’s wants.</p></div>
|
|
<div class="paragraph"><p>The server writes <em>shallow</em> lines for each
|
|
commit whose parents will not be sent as a result. The server writes
|
|
an <em>unshallow</em> line for each commit which the client has indicated is
|
|
shallow, but is no longer shallow at the currently requested depth
|
|
(that is, its parents will now be sent). The server MUST NOT mark
|
|
as unshallow anything which the client has not indicated was shallow.</p></div>
|
|
<div class="paragraph"><p>Now the client will send a list of the obj-ids it has using <em>have</em>
|
|
lines, so the server can make a packfile that only contains the objects
|
|
that the client needs. In multi_ack mode, the canonical implementation
|
|
will send up to 32 of these at a time, then will send a flush-pkt. The
|
|
canonical implementation will skip ahead and send the next 32 immediately,
|
|
so that there is always a block of 32 "in-flight on the wire" at a time.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> upload-haves = have-list
|
|
compute-end
|
|
|
|
have-list = *have-line
|
|
have-line = PKT-LINE("have" SP obj-id)
|
|
compute-end = flush-pkt / PKT-LINE("done")</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>If the server reads <em>have</em> lines, it then will respond by ACKing any
|
|
of the obj-ids the client said it had that the server also has. The
|
|
server will ACK obj-ids differently depending on which ack mode is
|
|
chosen by the client.</p></div>
|
|
<div class="paragraph"><p>In multi_ack mode:</p></div>
|
|
<div class="ulist"><ul>
|
|
<li>
|
|
<p>
|
|
the server will respond with <em>ACK obj-id continue</em> for any common
|
|
commits.
|
|
</p>
|
|
</li>
|
|
<li>
|
|
<p>
|
|
once the server has found an acceptable common base commit and is
|
|
ready to make a packfile, it will blindly ACK all <em>have</em> obj-ids
|
|
back to the client.
|
|
</p>
|
|
</li>
|
|
<li>
|
|
<p>
|
|
the server will then send a <em>NAK</em> and then wait for another response
|
|
from the client - either a <em>done</em> or another list of <em>have</em> lines.
|
|
</p>
|
|
</li>
|
|
</ul></div>
|
|
<div class="paragraph"><p>In multi_ack_detailed mode:</p></div>
|
|
<div class="ulist"><ul>
|
|
<li>
|
|
<p>
|
|
the server will differentiate the ACKs where it is signaling
|
|
that it is ready to send data with <em>ACK obj-id ready</em> lines, and
|
|
signals the identified common commits with <em>ACK obj-id common</em> lines.
|
|
</p>
|
|
</li>
|
|
</ul></div>
|
|
<div class="paragraph"><p>Without either multi_ack or multi_ack_detailed:</p></div>
|
|
<div class="ulist"><ul>
|
|
<li>
|
|
<p>
|
|
upload-pack sends "ACK obj-id" on the first common object it finds.
|
|
After that it says nothing until the client gives it a "done".
|
|
</p>
|
|
</li>
|
|
<li>
|
|
<p>
|
|
upload-pack sends "NAK" on a flush-pkt if no common object
|
|
has been found yet. If one has been found, and thus an ACK
|
|
was already sent, it’s silent on the flush-pkt.
|
|
</p>
|
|
</li>
|
|
</ul></div>
|
|
<div class="paragraph"><p>After the client has gotten enough ACK responses that it can determine
|
|
that the server has enough information to send an efficient packfile
|
|
(in the canonical implementation, this is determined when it has received
|
|
enough ACKs that it can color everything left in the --date-order queue
|
|
as common with the server, or the --date-order queue is empty), or the
|
|
client determines that it wants to give up (in the canonical implementation,
|
|
this is determined when the client sends 256 <em>have</em> lines without getting
|
|
any of them ACKed by the server - meaning there is nothing in common and
|
|
the server should just send all of its objects), then the client will send
|
|
a <em>done</em> command. The <em>done</em> command signals to the server that the client
|
|
is ready to receive its packfile data.</p></div>
|
|
<div class="paragraph"><p>However, the 256 limit <strong>only</strong> turns on in the canonical client
|
|
implementation if we have received at least one "ACK %s continue"
|
|
during a prior round. This helps to ensure that at least one common
|
|
ancestor is found before we give up entirely.</p></div>
|
|
<div class="paragraph"><p>Once the <em>done</em> line is read from the client, the server will either
|
|
send a final <em>ACK obj-id</em> or it will send a <em>NAK</em>. <em>obj-id</em> is the object
|
|
name of the last commit determined to be common. The server only sends
|
|
ACK after <em>done</em> if there is at least one common base and multi_ack or
|
|
multi_ack_detailed is enabled. The server always sends NAK after <em>done</em>
|
|
if there is no common base found.</p></div>
|
|
<div class="paragraph"><p>Instead of <em>ACK</em> or <em>NAK</em>, the server may send an error message (for
|
|
example, if it does not recognize an object in a <em>want</em> line received
|
|
from the client).</p></div>
|
|
<div class="paragraph"><p>Then the server will start sending its packfile data.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> server-response = *ack_multi ack / nak
|
|
ack_multi = PKT-LINE("ACK" SP obj-id ack_status)
|
|
ack_status = "continue" / "common" / "ready"
|
|
ack = PKT-LINE("ACK" SP obj-id)
|
|
nak = PKT-LINE("NAK")</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>A simple clone may look like this (with no <em>have</em> lines):</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> C: 0054want 74730d410fcb6603ace96f1dc55ea6196122532d multi_ack \
|
|
side-band-64k ofs-delta\n
|
|
C: 0032want 7d1665144a3a975c05f1f43902ddaf084e784dbe\n
|
|
C: 0032want 5a3f6be755bbb7deae50065988cbfa1ffa9ab68a\n
|
|
C: 0032want 7e47fe2bd8d01d481f44d7af0531bd93d3b21c01\n
|
|
C: 0032want 74730d410fcb6603ace96f1dc55ea6196122532d\n
|
|
C: 0000
|
|
C: 0009done\n
|
|
|
|
S: 0008NAK\n
|
|
S: [PACKFILE]</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>An incremental update (fetch) response might look like this:</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> C: 0054want 74730d410fcb6603ace96f1dc55ea6196122532d multi_ack \
|
|
side-band-64k ofs-delta\n
|
|
C: 0032want 7d1665144a3a975c05f1f43902ddaf084e784dbe\n
|
|
C: 0032want 5a3f6be755bbb7deae50065988cbfa1ffa9ab68a\n
|
|
C: 0000
|
|
C: 0032have 7e47fe2bd8d01d481f44d7af0531bd93d3b21c01\n
|
|
C: [30 more have lines]
|
|
C: 0032have 74730d410fcb6603ace96f1dc55ea6196122532d\n
|
|
C: 0000
|
|
|
|
S: 003aACK 7e47fe2bd8d01d481f44d7af0531bd93d3b21c01 continue\n
|
|
S: 003aACK 74730d410fcb6603ace96f1dc55ea6196122532d continue\n
|
|
S: 0008NAK\n
|
|
|
|
C: 0009done\n
|
|
|
|
S: 0031ACK 74730d410fcb6603ace96f1dc55ea6196122532d\n
|
|
S: [PACKFILE]</code></pre>
|
|
</div></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_packfile_data">Packfile Data</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>Now that the client and server have finished negotiation about what
|
|
the minimal amount of data that needs to be sent to the client is, the server
|
|
will construct and send the required data in packfile format.</p></div>
|
|
<div class="paragraph"><p>See <a href="gitformat-pack.html">gitformat-pack(5)</a> for what the packfile itself actually looks like.</p></div>
|
|
<div class="paragraph"><p>If <em>side-band</em> or <em>side-band-64k</em> capabilities have been specified by
|
|
the client, the server will send the packfile data multiplexed.</p></div>
|
|
<div class="paragraph"><p>Each packet starting with the packet-line length of the amount of data
|
|
that follows, followed by a single byte specifying the sideband the
|
|
following data is coming in on.</p></div>
|
|
<div class="paragraph"><p>In <em>side-band</em> mode, it will send up to 999 data bytes plus 1 control
|
|
code, for a total of up to 1000 bytes in a pkt-line. In <em>side-band-64k</em>
|
|
mode it will send up to 65519 data bytes plus 1 control code, for a
|
|
total of up to 65520 bytes in a pkt-line.</p></div>
|
|
<div class="paragraph"><p>The sideband byte will be a <em>1</em>, <em>2</em> or a <em>3</em>. Sideband <em>1</em> will contain
|
|
packfile data, sideband <em>2</em> will be used for progress information that the
|
|
client will generally print to stderr and sideband <em>3</em> is used for error
|
|
information.</p></div>
|
|
<div class="paragraph"><p>If no <em>side-band</em> capability was specified, the server will stream the
|
|
entire packfile without multiplexing.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_pushing_data_to_a_server">Pushing Data To a Server</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>Pushing data to a server will invoke the <em>receive-pack</em> process on the
|
|
server, which will allow the client to tell it which references it should
|
|
update and then send all the data the server will need for those new
|
|
references to be complete. Once all the data is received and validated,
|
|
the server will then update its references to what the client specified.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_authentication">Authentication</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>The protocol itself contains no authentication mechanisms. That is to be
|
|
handled by the transport, such as SSH, before the <em>receive-pack</em> process is
|
|
invoked. If <em>receive-pack</em> is configured over the Git transport, those
|
|
repositories will be writable by anyone who can access that port (9418) as
|
|
that transport is unauthenticated.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_reference_discovery_2">Reference Discovery</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>The reference discovery phase is done nearly the same way as it is in the
|
|
fetching protocol. Each reference obj-id and name on the server is sent
|
|
in packet-line format to the client, followed by a flush-pkt. The only
|
|
real difference is that the capability listing is different - the only
|
|
possible values are <em>report-status</em>, <em>report-status-v2</em>, <em>delete-refs</em>,
|
|
<em>ofs-delta</em>, <em>atomic</em> and <em>push-options</em>.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_reference_update_request_and_packfile_transfer">Reference Update Request and Packfile Transfer</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>Once the client knows what references the server is at, it can send a
|
|
list of reference update requests. For each reference on the server
|
|
that it wants to update, it sends a line listing the obj-id currently on
|
|
the server, the obj-id the client would like to update it to and the name
|
|
of the reference.</p></div>
|
|
<div class="paragraph"><p>This list is followed by a flush-pkt.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> update-requests = *shallow ( command-list | push-cert )
|
|
|
|
shallow = PKT-LINE("shallow" SP obj-id)
|
|
|
|
command-list = PKT-LINE(command NUL capability-list)
|
|
*PKT-LINE(command)
|
|
flush-pkt
|
|
|
|
command = create / delete / update
|
|
create = zero-id SP new-id SP name
|
|
delete = old-id SP zero-id SP name
|
|
update = old-id SP new-id SP name
|
|
|
|
old-id = obj-id
|
|
new-id = obj-id
|
|
|
|
push-cert = PKT-LINE("push-cert" NUL capability-list LF)
|
|
PKT-LINE("certificate version 0.1" LF)
|
|
PKT-LINE("pusher" SP ident LF)
|
|
PKT-LINE("pushee" SP url LF)
|
|
PKT-LINE("nonce" SP nonce LF)
|
|
*PKT-LINE("push-option" SP push-option LF)
|
|
PKT-LINE(LF)
|
|
*PKT-LINE(command LF)
|
|
*PKT-LINE(gpg-signature-lines LF)
|
|
PKT-LINE("push-cert-end" LF)
|
|
|
|
push-option = 1*( VCHAR | SP )</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>If the server has advertised the <em>push-options</em> capability and the client has
|
|
specified <em>push-options</em> as part of the capability list above, the client then
|
|
sends its push options followed by a flush-pkt.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> push-options = *PKT-LINE(push-option) flush-pkt</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>For backwards compatibility with older Git servers, if the client sends a push
|
|
cert and push options, it MUST send its push options both embedded within the
|
|
push cert and after the push cert. (Note that the push options within the cert
|
|
are prefixed, but the push options after the cert are not.) Both these lists
|
|
MUST be the same, modulo the prefix.</p></div>
|
|
<div class="paragraph"><p>After that the packfile that
|
|
should contain all the objects that the server will need to complete the new
|
|
references will be sent.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> packfile = "PACK" 28*(OCTET)</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>If the receiving end does not support delete-refs, the sending end MUST
|
|
NOT ask for delete command.</p></div>
|
|
<div class="paragraph"><p>If the receiving end does not support push-cert, the sending end
|
|
MUST NOT send a push-cert command. When a push-cert command is
|
|
sent, command-list MUST NOT be sent; the commands recorded in the
|
|
push certificate is used instead.</p></div>
|
|
<div class="paragraph"><p>The packfile MUST NOT be sent if the only command used is <em>delete</em>.</p></div>
|
|
<div class="paragraph"><p>A packfile MUST be sent if either create or update command is used,
|
|
even if the server already has all the necessary objects. In this
|
|
case the client MUST send an empty packfile. The only time this
|
|
is likely to happen is if the client is creating
|
|
a new branch or a tag that points to an existing obj-id.</p></div>
|
|
<div class="paragraph"><p>The server will receive the packfile, unpack it, then validate each
|
|
reference that is being updated that it hasn’t changed while the request
|
|
was being processed (the obj-id is still the same as the old-id), and
|
|
it will run any update hooks to make sure that the update is acceptable.
|
|
If all of that is fine, the server will then update the references.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_push_certificate">Push Certificate</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>A push certificate begins with a set of header lines. After the
|
|
header and an empty line, the protocol commands follow, one per
|
|
line. Note that the trailing LF in push-cert PKT-LINEs is <em>not</em>
|
|
optional; it must be present.</p></div>
|
|
<div class="paragraph"><p>Currently, the following header fields are defined:</p></div>
|
|
<div class="dlist"><dl>
|
|
<dt class="hdlist1">
|
|
<code>pusher</code> ident
|
|
</dt>
|
|
<dd>
|
|
<p>
|
|
Identify the GPG key in "Human Readable Name <<a href="mailto:email@address">email@address</a>>"
|
|
format.
|
|
</p>
|
|
</dd>
|
|
<dt class="hdlist1">
|
|
<code>pushee</code> url
|
|
</dt>
|
|
<dd>
|
|
<p>
|
|
The repository URL (anonymized, if the URL contains
|
|
authentication material) the user who ran <code>git</code> <code>push</code>
|
|
intended to push into.
|
|
</p>
|
|
</dd>
|
|
<dt class="hdlist1">
|
|
<code>nonce</code> nonce
|
|
</dt>
|
|
<dd>
|
|
<p>
|
|
The <em>nonce</em> string the receiving repository asked the
|
|
pushing user to include in the certificate, to prevent
|
|
replay attacks.
|
|
</p>
|
|
</dd>
|
|
</dl></div>
|
|
<div class="paragraph"><p>The GPG signature lines are a detached signature for the contents
|
|
recorded in the push certificate before the signature block begins.
|
|
The detached signature is used to certify that the commands were
|
|
given by the pusher, who must be the signer.</p></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_report_status">Report Status</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>After receiving the pack data from the sender, the receiver sends a
|
|
report if <em>report-status</em> or <em>report-status-v2</em> capability is in effect.
|
|
It is a short listing of what happened in that update. It will first
|
|
list the status of the packfile unpacking as either <em>unpack ok</em> or
|
|
<em>unpack [error]</em>. Then it will list the status for each of the references
|
|
that it tried to update. Each line is either <em>ok [refname]</em> if the
|
|
update was successful, or <em>ng [refname] [error]</em> if the update was not.</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> report-status = unpack-status
|
|
1*(command-status)
|
|
flush-pkt
|
|
|
|
unpack-status = PKT-LINE("unpack" SP unpack-result)
|
|
unpack-result = "ok" / error-msg
|
|
|
|
command-status = command-ok / command-fail
|
|
command-ok = PKT-LINE("ok" SP refname)
|
|
command-fail = PKT-LINE("ng" SP refname SP error-msg)
|
|
|
|
error-msg = 1*(OCTET) ; where not "ok"</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>The <em>report-status-v2</em> capability extends the protocol by adding new option
|
|
lines in order to support reporting of reference rewritten by the
|
|
<em>proc-receive</em> hook. The <em>proc-receive</em> hook may handle a command for a
|
|
pseudo-reference which may create or update one or more references, and each
|
|
reference may have different name, different new-oid, and different old-oid.</p></div>
|
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<div class="listingblock">
|
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<div class="content">
|
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<pre><code> report-status-v2 = unpack-status
|
|
1*(command-status-v2)
|
|
flush-pkt
|
|
|
|
unpack-status = PKT-LINE("unpack" SP unpack-result)
|
|
unpack-result = "ok" / error-msg
|
|
|
|
command-status-v2 = command-ok-v2 / command-fail
|
|
command-ok-v2 = command-ok
|
|
*option-line
|
|
|
|
command-ok = PKT-LINE("ok" SP refname)
|
|
command-fail = PKT-LINE("ng" SP refname SP error-msg)
|
|
|
|
error-msg = 1*(OCTET) ; where not "ok"
|
|
|
|
option-line = *1(option-refname)
|
|
*1(option-old-oid)
|
|
*1(option-new-oid)
|
|
*1(option-forced-update)
|
|
|
|
option-refname = PKT-LINE("option" SP "refname" SP refname)
|
|
option-old-oid = PKT-LINE("option" SP "old-oid" SP obj-id)
|
|
option-new-oid = PKT-LINE("option" SP "new-oid" SP obj-id)
|
|
option-force = PKT-LINE("option" SP "forced-update")</code></pre>
|
|
</div></div>
|
|
<div class="paragraph"><p>Updates can be unsuccessful for a number of reasons. The reference can have
|
|
changed since the reference discovery phase was originally sent, meaning
|
|
someone pushed in the meantime. The reference being pushed could be a
|
|
non-fast-forward reference and the update hooks or configuration could be
|
|
set to not allow that, etc. Also, some references can be updated while others
|
|
can be rejected.</p></div>
|
|
<div class="paragraph"><p>An example client/server communication might look like this:</p></div>
|
|
<div class="listingblock">
|
|
<div class="content">
|
|
<pre><code> S: 006274730d410fcb6603ace96f1dc55ea6196122532d refs/heads/local\0report-status delete-refs ofs-delta\n
|
|
S: 003e7d1665144a3a975c05f1f43902ddaf084e784dbe refs/heads/debug\n
|
|
S: 003f74730d410fcb6603ace96f1dc55ea6196122532d refs/heads/master\n
|
|
S: 003d74730d410fcb6603ace96f1dc55ea6196122532d refs/heads/team\n
|
|
S: 0000
|
|
|
|
C: 00677d1665144a3a975c05f1f43902ddaf084e784dbe 74730d410fcb6603ace96f1dc55ea6196122532d refs/heads/debug\n
|
|
C: 006874730d410fcb6603ace96f1dc55ea6196122532d 5a3f6be755bbb7deae50065988cbfa1ffa9ab68a refs/heads/master\n
|
|
C: 0000
|
|
C: [PACKDATA]
|
|
|
|
S: 000eunpack ok\n
|
|
S: 0018ok refs/heads/debug\n
|
|
S: 002ang refs/heads/master non-fast-forward\n</code></pre>
|
|
</div></div>
|
|
</div>
|
|
</div>
|
|
<div class="sect1">
|
|
<h2 id="_git">GIT</h2>
|
|
<div class="sectionbody">
|
|
<div class="paragraph"><p>Part of the <a href="git.html">git(1)</a> suite</p></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div id="footnotes"><hr /></div>
|
|
<div id="footer">
|
|
<div id="footer-text">
|
|
Last updated
|
|
2025-08-18 02:18:23 CEST
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