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-rw-r--r--src/common/ConfUtils.cc347
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diff --git a/src/common/ConfUtils.cc b/src/common/ConfUtils.cc
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+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2011 New Dream Network
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ *
+ */
+// #define BOOST_SPIRIT_DEBUG
+
+#include <algorithm>
+#include <cctype>
+#include <experimental/iterator>
+#include <fstream>
+#include <iostream>
+#include <iterator>
+#include <map>
+#include <sstream>
+
+#if __has_include(<filesystem>)
+#include <filesystem>
+namespace fs = std::filesystem;
+#elif __has_include(<experimental/filesystem>)
+#include <experimental/filesystem>
+namespace fs = std::experimental::filesystem;
+#else
+#error std::filesystem not available!
+#endif
+
+#include <boost/algorithm/string.hpp>
+#include <boost/algorithm/string/trim_all.hpp>
+#include <boost/spirit/include/qi.hpp>
+#include <boost/spirit/include/phoenix.hpp>
+#include <boost/spirit/include/support_line_pos_iterator.hpp>
+
+#include "include/buffer.h"
+#include "common/errno.h"
+#include "common/utf8.h"
+#include "common/ConfUtils.h"
+
+using std::ostringstream;
+using std::string;
+
+#define MAX_CONFIG_FILE_SZ 0x40000000
+
+conf_line_t::conf_line_t(const std::string& key, const std::string& val)
+ : key{ConfFile::normalize_key_name(key)},
+ val{boost::algorithm::trim_copy_if(
+ val,
+ [](unsigned char c) {
+ return std::isspace(c);
+ })}
+{}
+
+bool conf_line_t::operator<(const conf_line_t &rhs) const
+{
+ // We only compare keys.
+ // If you have more than one line with the same key in a given section, the
+ // last one wins.
+ return key < rhs.key;
+}
+
+std::ostream &operator<<(std::ostream& oss, const conf_line_t &l)
+{
+ oss << "conf_line_t(key = '" << l.key << "', val='" << l.val << "')";
+ return oss;
+}
+
+conf_section_t::conf_section_t(const std::string& heading,
+ const std::vector<conf_line_t>& lines)
+ : heading{heading}
+{
+ for (auto& line : lines) {
+ auto [where, inserted] = insert(line);
+ if (!inserted) {
+ erase(where);
+ insert(line);
+ }
+ }
+}
+
+///////////////////////// ConfFile //////////////////////////
+
+ConfFile::ConfFile(const std::vector<conf_section_t>& sections)
+{
+ for (auto& section : sections) {
+ auto [old_sec, sec_inserted] = emplace(section.heading, section);
+ if (!sec_inserted) {
+ // merge lines in section into old_sec
+ for (auto& line : section) {
+ auto [old_line, line_inserted] = old_sec->second.emplace(line);
+ // and replace the existing ones if any
+ if (!line_inserted) {
+ old_sec->second.erase(old_line);
+ old_sec->second.insert(line);
+ }
+ }
+ }
+ }
+}
+
+/* We load the whole file into memory and then parse it. Although this is not
+ * the optimal approach, it does mean that most of this code can be shared with
+ * the bufferlist loading function. Since bufferlists are always in-memory, the
+ * load_from_buffer interface works well for them.
+ * In general, configuration files should be a few kilobytes at maximum, so
+ * loading the whole configuration into memory shouldn't be a problem.
+ */
+int ConfFile::parse_file(const std::string &fname,
+ std::ostream *warnings)
+{
+ clear();
+ try {
+ if (auto file_size = fs::file_size(fname); file_size > MAX_CONFIG_FILE_SZ) {
+ *warnings << __func__ << ": config file '" << fname
+ << "' is " << file_size << " bytes, "
+ << "but the maximum is " << MAX_CONFIG_FILE_SZ;
+ return -EINVAL;
+ }
+ } catch (const fs::filesystem_error& e) {
+ std::error_code ec;
+ auto is_other = fs::is_other(fname, ec);
+ if (!ec && is_other) {
+ // /dev/null?
+ return 0;
+ } else {
+ *warnings << __func__ << ": " << e.what();
+ return -e.code().value();
+ }
+ }
+ std::ifstream ifs{fname};
+ std::string buffer{std::istreambuf_iterator<char>(ifs),
+ std::istreambuf_iterator<char>()};
+ if (parse_buffer(buffer, warnings)) {
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+namespace {
+
+namespace qi = boost::spirit::qi;
+namespace phoenix = boost::phoenix;
+
+template<typename Iterator, typename Skipper>
+struct IniGrammer : qi::grammar<Iterator, ConfFile(), Skipper>
+{
+ struct error_handler_t {
+ std::ostream& os;
+ template<typename Iter>
+ auto operator()(Iter first, Iter last, Iter where,
+ const boost::spirit::info& what) const {
+ auto line_start = boost::spirit::get_line_start(first, where);
+ os << "parse error: expected '" << what
+ << "' in line " << boost::spirit::get_line(where)
+ << " at position " << boost::spirit::get_column(line_start, where) << "\n";
+ return qi::fail;
+ }
+ };
+ IniGrammer(Iterator begin, std::ostream& err)
+ : IniGrammer::base_type{conf_file},
+ report_error{error_handler_t{err}}
+ {
+ using qi::_1;
+ using qi::_2;
+ using qi::_val;
+ using qi::char_;
+ using qi::eoi;
+ using qi::eol;
+ using qi::blank;
+ using qi::lexeme;
+ using qi::lit;
+ using qi::raw;
+
+ blanks = *blank;
+ comment_start = lit('#') | lit(';');
+ continue_marker = lit('\\') >> eol;
+
+ text_char %=
+ (lit('\\') >> (char_ - eol)) |
+ (char_ - (comment_start | eol));
+
+ key %= raw[+(text_char - char_("=[ ")) % +blank];
+ quoted_value %=
+ lexeme[lit('"') >> *(text_char - '"') > '"'] |
+ lexeme[lit('\'') >> *(text_char - '\'') > '\''];
+ unquoted_value %= *text_char;
+ comment = *blank >> comment_start > *(char_ - eol);
+ empty_line = -(blanks|comment) >> eol;
+ value %= quoted_value | unquoted_value;
+ key_val =
+ (blanks >> key >> blanks >> '=' > blanks > value > +empty_line)
+ [_val = phoenix::construct<conf_line_t>(_1, _2)];
+
+ heading %= lit('[') > +(text_char - ']') > ']' > +empty_line;
+ section =
+ (heading >> *(key_val - heading) >> *eol)
+ [_val = phoenix::construct<conf_section_t>(_1, _2)];
+ conf_file =
+ (key_val [_val = phoenix::construct<ConfFile>(_1)]
+ |
+ (*eol >> (*section)[_val = phoenix::construct<ConfFile>(_1)])
+ ) > eoi;
+
+ empty_line.name("empty_line");
+ key.name("key");
+ quoted_value.name("quoted value");
+ unquoted_value.name("unquoted value");
+ key_val.name("key=val");
+ heading.name("section name");
+ section.name("section");
+
+ qi::on_error<qi::fail>(
+ conf_file,
+ report_error(qi::_1, qi::_2, qi::_3, qi::_4));
+
+ BOOST_SPIRIT_DEBUG_NODE(heading);
+ BOOST_SPIRIT_DEBUG_NODE(section);
+ BOOST_SPIRIT_DEBUG_NODE(key);
+ BOOST_SPIRIT_DEBUG_NODE(quoted_value);
+ BOOST_SPIRIT_DEBUG_NODE(unquoted_value);
+ BOOST_SPIRIT_DEBUG_NODE(key_val);
+ BOOST_SPIRIT_DEBUG_NODE(conf_file);
+ }
+
+ qi::rule<Iterator> blanks;
+ qi::rule<Iterator> empty_line;
+ qi::rule<Iterator> comment_start;
+ qi::rule<Iterator> continue_marker;
+ qi::rule<Iterator, char()> text_char;
+ qi::rule<Iterator, std::string(), Skipper> key;
+ qi::rule<Iterator, std::string(), Skipper> quoted_value;
+ qi::rule<Iterator, std::string(), Skipper> unquoted_value;
+ qi::rule<Iterator> comment;
+ qi::rule<Iterator, std::string(), Skipper> value;
+ qi::rule<Iterator, conf_line_t(), Skipper> key_val;
+ qi::rule<Iterator, std::string(), Skipper> heading;
+ qi::rule<Iterator, conf_section_t(), Skipper> section;
+ qi::rule<Iterator, ConfFile(), Skipper> conf_file;
+ boost::phoenix::function<error_handler_t> report_error;
+};
+}
+
+bool ConfFile::parse_buffer(std::string_view buf, std::ostream* err)
+{
+ assert(err);
+#ifdef _WIN32
+ // We'll need to ensure that there's a new line at the end of the buffer,
+ // otherwise the config parsing will fail.
+ std::string _buf = std::string(buf) + "\n";
+#else
+ std::string_view _buf = buf;
+#endif
+ if (int err_pos = check_utf8(_buf.data(), _buf.size()); err_pos > 0) {
+ *err << "parse error: invalid UTF-8 found at line "
+ << std::count(_buf.begin(), std::next(_buf.begin(), err_pos), '\n') + 1;
+ return false;
+ }
+ using iter_t = boost::spirit::line_pos_iterator<decltype(_buf.begin())>;
+ iter_t first{_buf.begin()};
+ using skipper_t = qi::rule<iter_t>;
+ IniGrammer<iter_t, skipper_t> grammar{first, *err};
+ skipper_t skipper = grammar.continue_marker | grammar.comment;
+ return qi::phrase_parse(first, iter_t{_buf.end()},
+ grammar, skipper, *this);
+}
+
+int ConfFile::parse_bufferlist(ceph::bufferlist *bl,
+ std::ostream *warnings)
+{
+ clear();
+ ostringstream oss;
+ if (!warnings) {
+ warnings = &oss;
+ }
+ return parse_buffer({bl->c_str(), bl->length()}, warnings) ? 0 : -EINVAL;
+}
+
+int ConfFile::read(std::string_view section_name,
+ std::string_view key,
+ std::string &val) const
+{
+ string k(normalize_key_name(key));
+
+ if (auto s = base_type::find(section_name); s != end()) {
+ conf_line_t exemplar{k, {}};
+ if (auto line = s->second.find(exemplar); line != s->second.end()) {
+ val = line->val;
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+/* Normalize a key name.
+ *
+ * Normalized key names have no leading or trailing whitespace, and all
+ * whitespace is stored as underscores. The main reason for selecting this
+ * normal form is so that in common/config.cc, we can use a macro to stringify
+ * the field names of md_config_t and get a key in normal form.
+ */
+std::string ConfFile::normalize_key_name(std::string_view key)
+{
+ std::string k{key};
+ boost::algorithm::trim_fill_if(k, "_", isspace);
+ return k;
+}
+
+void ConfFile::check_old_style_section_names(const std::vector<std::string>& prefixes,
+ std::ostream& os)
+{
+ // Warn about section names that look like old-style section names
+ std::vector<std::string> old_style_section_names;
+ for (auto& [name, section] : *this) {
+ for (auto& prefix : prefixes) {
+ if (name.find(prefix) == 0 && name.size() > 3 && name[3] != '.') {
+ old_style_section_names.push_back(name);
+ }
+ }
+ }
+ if (!old_style_section_names.empty()) {
+ os << "ERROR! old-style section name(s) found: ";
+ std::copy(std::begin(old_style_section_names),
+ std::end(old_style_section_names),
+ std::experimental::make_ostream_joiner(os, ", "));
+ os << ". Please use the new style section names that include a period.";
+ }
+}
+
+std::ostream &operator<<(std::ostream &oss, const ConfFile &cf)
+{
+ for (auto& [name, section] : cf) {
+ oss << "[" << name << "]\n";
+ for (auto& [key, val] : section) {
+ if (!key.empty()) {
+ oss << "\t" << key << " = \"" << val << "\"\n";
+ }
+ }
+ }
+ return oss;
+}
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