diff options
Diffstat (limited to 'src/libutil/strings.cc')
| -rw-r--r-- | src/libutil/strings.cc | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/src/libutil/strings.cc b/src/libutil/strings.cc new file mode 100644 index 000000000..9cb319cce --- /dev/null +++ b/src/libutil/strings.cc @@ -0,0 +1,232 @@ +#include "strings.hh" + +namespace nix { + +std::vector<char *> stringsToCharPtrs(const Strings & ss) +{ + std::vector<char *> res; + for (auto & s : ss) res.push_back((char *) s.c_str()); + res.push_back(0); + return res; +} + + +template<class C> C tokenizeString(std::string_view s, std::string_view separators) +{ + C result; + auto pos = s.find_first_not_of(separators, 0); + while (pos != std::string_view::npos) { + auto end = s.find_first_of(separators, pos + 1); + if (end == std::string_view::npos) end = s.size(); + result.insert(result.end(), std::string(s, pos, end - pos)); + pos = s.find_first_not_of(separators, end); + } + return result; +} + +template Strings tokenizeString(std::string_view s, std::string_view separators); +template StringSet tokenizeString(std::string_view s, std::string_view separators); +template std::vector<std::string> tokenizeString(std::string_view s, std::string_view separators); + + +std::string chomp(std::string_view s) +{ + size_t i = s.find_last_not_of(" \n\r\t"); + return i == std::string_view::npos ? "" : std::string(s, 0, i + 1); +} + + +std::string trim(std::string_view s, std::string_view whitespace) +{ + auto i = s.find_first_not_of(whitespace); + if (i == s.npos) return ""; + auto j = s.find_last_not_of(whitespace); + return std::string(s, i, j == s.npos ? j : j - i + 1); +} + + +std::string replaceStrings( + std::string res, + std::string_view from, + std::string_view to) +{ + if (from.empty()) return res; + size_t pos = 0; + while ((pos = res.find(from, pos)) != std::string::npos) { + res.replace(pos, from.size(), to); + pos += to.size(); + } + return res; +} + + +Rewriter::Rewriter(std::map<std::string, std::string> rewrites) + : rewrites(std::move(rewrites)) +{ + for (const auto & [k, v] : this->rewrites) { + assert(!k.empty()); + initials.push_back(k[0]); + } + std::ranges::sort(initials); + auto [firstDupe, end] = std::ranges::unique(initials); + initials.erase(firstDupe, end); +} + +std::string Rewriter::operator()(std::string s) +{ + size_t j = 0; + while ((j = s.find_first_of(initials, j)) != std::string::npos) { + size_t skip = 1; + for (auto & [from, to] : rewrites) { + if (s.compare(j, from.size(), from) == 0) { + s.replace(j, from.size(), to); + skip = to.size(); + break; + } + } + j += skip; + } + return s; +} + + +std::string toLower(const std::string & s) +{ + std::string r(s); + for (auto & c : r) + c = std::tolower(c); + return r; +} + + +std::string shellEscape(const std::string_view s) +{ + std::string r; + r.reserve(s.size() + 2); + r += "'"; + for (auto & i : s) + if (i == '\'') r += "'\\''"; else r += i; + r += '\''; + return r; +} + +constexpr char base64Chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +std::string base64Encode(std::string_view s) +{ + std::string res; + res.reserve((s.size() + 2) / 3 * 4); + int data = 0, nbits = 0; + + for (char c : s) { + data = data << 8 | (unsigned char) c; + nbits += 8; + while (nbits >= 6) { + nbits -= 6; + res.push_back(base64Chars[data >> nbits & 0x3f]); + } + } + + if (nbits) res.push_back(base64Chars[data << (6 - nbits) & 0x3f]); + while (res.size() % 4) res.push_back('='); + + return res; +} + + +std::string base64Decode(std::string_view s) +{ + constexpr char npos = -1; + constexpr std::array<char, 256> base64DecodeChars = [&]() { + std::array<char, 256> result{}; + for (auto& c : result) + c = npos; + for (int i = 0; i < 64; i++) + result[base64Chars[i]] = i; + return result; + }(); + + std::string res; + // Some sequences are missing the padding consisting of up to two '='. + // vvv + res.reserve((s.size() + 2) / 4 * 3); + unsigned int d = 0, bits = 0; + + for (char c : s) { + if (c == '=') break; + if (c == '\n') continue; + + char digit = base64DecodeChars[(unsigned char) c]; + if (digit == npos) + throw Error("invalid character in Base64 string: '%c'", c); + + bits += 6; + d = d << 6 | digit; + if (bits >= 8) { + res.push_back(d >> (bits - 8) & 0xff); + bits -= 8; + } + } + + return res; +} + + +std::string stripIndentation(std::string_view s) +{ + size_t minIndent = 10000; + size_t curIndent = 0; + bool atStartOfLine = true; + + for (auto & c : s) { + if (atStartOfLine && c == ' ') + curIndent++; + else if (c == '\n') { + if (atStartOfLine) + minIndent = std::max(minIndent, curIndent); + curIndent = 0; + atStartOfLine = true; + } else { + if (atStartOfLine) { + minIndent = std::min(minIndent, curIndent); + atStartOfLine = false; + } + } + } + + std::string res; + + size_t pos = 0; + while (pos < s.size()) { + auto eol = s.find('\n', pos); + if (eol == s.npos) eol = s.size(); + if (eol - pos > minIndent) + res.append(s.substr(pos + minIndent, eol - pos - minIndent)); + res.push_back('\n'); + pos = eol + 1; + } + + return res; +} + + +std::pair<std::string_view, std::string_view> getLine(std::string_view s) +{ + auto newline = s.find('\n'); + + if (newline == s.npos) { + return {s, ""}; + } else { + auto line = s.substr(0, newline); + if (!line.empty() && line[line.size() - 1] == '\r') + line = line.substr(0, line.size() - 1); + return {line, s.substr(newline + 1)}; + } +} + +std::string showBytes(uint64_t bytes) +{ + return fmt("%.2f MiB", bytes / (1024.0 * 1024.0)); +} + +} |