diff options
Diffstat (limited to 'src/libutil/util.cc')
| -rw-r--r-- | src/libutil/util.cc | 200 |
1 files changed, 131 insertions, 69 deletions
diff --git a/src/libutil/util.cc b/src/libutil/util.cc index cd359cfee..c075a14b4 100644 --- a/src/libutil/util.cc +++ b/src/libutil/util.cc @@ -71,13 +71,11 @@ void clearEnv() unsetenv(name.first.c_str()); } -void replaceEnv(std::map<std::string, std::string> newEnv) +void replaceEnv(const std::map<std::string, std::string> & newEnv) { clearEnv(); - for (auto newEnvVar : newEnv) - { + for (auto & newEnvVar : newEnv) setenv(newEnvVar.first.c_str(), newEnvVar.second.c_str(), 1); - } } @@ -110,13 +108,13 @@ Path canonPath(PathView path, bool resolveSymlinks) { assert(path != ""); - string s; + std::string s; s.reserve(256); if (path[0] != '/') throw Error("not an absolute path: '%1%'", path); - string temp; + std::string temp; /* Count the number of times we follow a symlink and stop at some arbitrary (but high) limit to prevent infinite loops. */ @@ -142,7 +140,7 @@ Path canonPath(PathView path, bool resolveSymlinks) /* Normal component; copy it. */ else { s += '/'; - if (const auto slash = path.find('/'); slash == string::npos) { + if (const auto slash = path.find('/'); slash == std::string::npos) { s += path; path = {}; } else { @@ -175,7 +173,7 @@ Path canonPath(PathView path, bool resolveSymlinks) Path dirOf(const PathView path) { Path::size_type pos = path.rfind('/'); - if (pos == string::npos) + if (pos == std::string::npos) return "."; return pos == 0 ? "/" : Path(path, 0, pos); } @@ -191,7 +189,7 @@ std::string_view baseNameOf(std::string_view path) last -= 1; auto pos = path.rfind('/', last); - if (pos == string::npos) + if (pos == std::string::npos) pos = 0; else pos += 1; @@ -249,7 +247,7 @@ Path readLink(const Path & path) else throw SysError("reading symbolic link '%1%'", path); else if (rlSize < bufSize) - return string(buf.data(), rlSize); + return std::string(buf.data(), rlSize); } } @@ -269,7 +267,7 @@ DirEntries readDirectory(DIR *dir, const Path & path) struct dirent * dirent; while (errno = 0, dirent = readdir(dir)) { /* sic */ checkInterrupt(); - string name = dirent->d_name; + std::string name = dirent->d_name; if (name == "." || name == "..") continue; entries.emplace_back(name, dirent->d_ino, #ifdef HAVE_STRUCT_DIRENT_D_TYPE @@ -303,7 +301,7 @@ unsigned char getFileType(const Path & path) } -string readFile(int fd) +std::string readFile(int fd) { struct stat st; if (fstat(fd, &st) == -1) @@ -313,7 +311,7 @@ string readFile(int fd) } -string readFile(const Path & path) +std::string readFile(const Path & path) { AutoCloseFD fd = open(path.c_str(), O_RDONLY | O_CLOEXEC); if (!fd) @@ -366,9 +364,9 @@ void writeFile(const Path & path, Source & source, mode_t mode) } } -string readLine(int fd) +std::string readLine(int fd) { - string s; + std::string s; while (1) { checkInterrupt(); char ch; @@ -387,7 +385,7 @@ string readLine(int fd) } -void writeLine(int fd, string s) +void writeLine(int fd, std::string s) { s += '\n'; writeFull(fd, s); @@ -398,7 +396,7 @@ static void _deletePath(int parentfd, const Path & path, uint64_t & bytesFreed) { checkInterrupt(); - string name(baseNameOf(path)); + std::string name(baseNameOf(path)); struct stat st; if (fstatat(parentfd, name.c_str(), &st, AT_SYMLINK_NOFOLLOW) == -1) { @@ -406,8 +404,29 @@ static void _deletePath(int parentfd, const Path & path, uint64_t & bytesFreed) throw SysError("getting status of '%1%'", path); } - if (!S_ISDIR(st.st_mode) && st.st_nlink == 1) - bytesFreed += st.st_size; + if (!S_ISDIR(st.st_mode)) { + /* We are about to delete a file. Will it likely free space? */ + + switch (st.st_nlink) { + /* Yes: last link. */ + case 1: + bytesFreed += st.st_size; + break; + /* Maybe: yes, if 'auto-optimise-store' or manual optimisation + was performed. Instead of checking for real let's assume + it's an optimised file and space will be freed. + + In worst case we will double count on freed space for files + with exactly two hardlinks for unoptimised packages. + */ + case 2: + bytesFreed += st.st_size; + break; + /* No: 3+ links. */ + default: + break; + } + } if (S_ISDIR(st.st_mode)) { /* Make the directory accessible. */ @@ -566,8 +585,8 @@ Path getConfigDir() std::vector<Path> getConfigDirs() { Path configHome = getConfigDir(); - string configDirs = getEnv("XDG_CONFIG_DIRS").value_or("/etc/xdg"); - std::vector<Path> result = tokenizeString<std::vector<string>>(configDirs, ":"); + auto configDirs = getEnv("XDG_CONFIG_DIRS").value_or("/etc/xdg"); + std::vector<Path> result = tokenizeString<std::vector<std::string>>(configDirs, ":"); result.insert(result.begin(), configHome); return result; } @@ -670,7 +689,7 @@ void writeFull(int fd, std::string_view s, bool allowInterrupts) } -string drainFD(int fd, bool block, const size_t reserveSize) +std::string drainFD(int fd, bool block, const size_t reserveSize) { // the parser needs two extra bytes to append terminating characters, other users will // not care very much about the extra memory. @@ -682,7 +701,14 @@ string drainFD(int fd, bool block, const size_t reserveSize) void drainFD(int fd, Sink & sink, bool block) { - int saved; + // silence GCC maybe-uninitialized warning in finally + int saved = 0; + + if (!block) { + saved = fcntl(fd, F_GETFL); + if (fcntl(fd, F_SETFL, saved | O_NONBLOCK) == -1) + throw SysError("making file descriptor non-blocking"); + } Finally finally([&]() { if (!block) { @@ -691,12 +717,6 @@ void drainFD(int fd, Sink & sink, bool block) } }); - if (!block) { - saved = fcntl(fd, F_GETFL); - if (fcntl(fd, F_SETFL, saved | O_NONBLOCK) == -1) - throw SysError("making file descriptor non-blocking"); - } - std::vector<unsigned char> buf(64 * 1024); while (1) { checkInterrupt(); @@ -719,7 +739,7 @@ void drainFD(int fd, Sink & sink, bool block) AutoDelete::AutoDelete() : del{false} {} -AutoDelete::AutoDelete(const string & p, bool recursive) : path(p) +AutoDelete::AutoDelete(const std::string & p, bool recursive) : path(p) { del = true; this->recursive = recursive; @@ -1036,7 +1056,7 @@ std::vector<char *> stringsToCharPtrs(const Strings & ss) return res; } -string runProgram(Path program, bool searchPath, const Strings & args, +std::string runProgram(Path program, bool searchPath, const Strings & args, const std::optional<std::string> & input) { auto res = runProgram(RunOptions {.program = program, .searchPath = searchPath, .args = args, .input = input}); @@ -1174,7 +1194,7 @@ void runProgram2(const RunOptions & options) } -void closeMostFDs(const set<int> & exceptions) +void closeMostFDs(const std::set<int> & exceptions) { #if __linux__ try { @@ -1238,11 +1258,11 @@ void _interrupted() template<class C> C tokenizeString(std::string_view s, std::string_view separators) { C result; - string::size_type pos = s.find_first_not_of(separators, 0); - while (pos != string::npos) { - string::size_type end = s.find_first_of(separators, pos + 1); - if (end == string::npos) end = s.size(); - result.insert(result.end(), string(s, pos, end - pos)); + 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; @@ -1250,29 +1270,30 @@ template<class C> C tokenizeString(std::string_view s, std::string_view separato template Strings tokenizeString(std::string_view s, std::string_view separators); template StringSet tokenizeString(std::string_view s, std::string_view separators); -template vector<string> tokenizeString(std::string_view s, std::string_view separators); +template std::vector<std::string> tokenizeString(std::string_view s, std::string_view separators); -string chomp(std::string_view s) +std::string chomp(std::string_view s) { size_t i = s.find_last_not_of(" \n\r\t"); - return i == string::npos ? "" : string(s, 0, i + 1); + return i == std::string_view::npos ? "" : std::string(s, 0, i + 1); } -string trim(const string & s, const string & whitespace) +std::string trim(std::string_view s, std::string_view whitespace) { auto i = s.find_first_not_of(whitespace); - if (i == string::npos) return ""; + if (i == s.npos) return ""; auto j = s.find_last_not_of(whitespace); - return string(s, i, j == string::npos ? j : j - i + 1); + return std::string(s, i, j == s.npos ? j : j - i + 1); } -string replaceStrings(std::string_view s, - const std::string & from, const std::string & to) +std::string replaceStrings( + std::string res, + std::string_view from, + std::string_view to) { - string res(s); if (from.empty()) return res; size_t pos = 0; while ((pos = res.find(from, pos)) != std::string::npos) { @@ -1283,20 +1304,19 @@ string replaceStrings(std::string_view s, } -std::string rewriteStrings(const std::string & _s, const StringMap & rewrites) +std::string rewriteStrings(std::string s, const StringMap & rewrites) { - auto s = _s; for (auto & i : rewrites) { if (i.first == i.second) continue; size_t j = 0; - while ((j = s.find(i.first, j)) != string::npos) + while ((j = s.find(i.first, j)) != std::string::npos) s.replace(j, i.first.size(), i.second); } return s; } -string statusToString(int status) +std::string statusToString(int status) { if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { if (WIFEXITED(status)) @@ -1358,11 +1378,15 @@ std::string shellEscape(const std::string_view s) void ignoreException() { + /* Make sure no exceptions leave this function. + printError() also throws when remote is closed. */ try { - throw; - } catch (std::exception & e) { - printError("error (ignored): %1%", e.what()); - } + try { + throw; + } catch (std::exception & e) { + printError("error (ignored): %1%", e.what()); + } + } catch (...) { } } bool shouldANSI() @@ -1408,7 +1432,7 @@ std::string filterANSIEscapes(const std::string & s, bool filterAll, unsigned in } } - else if (*i == '\r') + else if (*i == '\r' || *i == '\a') // do nothing for now i++; @@ -1444,9 +1468,10 @@ std::string filterANSIEscapes(const std::string & s, bool filterAll, unsigned in constexpr char base64Chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; -string base64Encode(std::string_view s) +std::string base64Encode(std::string_view s) { - string res; + std::string res; + res.reserve((s.size() + 2) / 3 * 4); int data = 0, nbits = 0; for (char c : s) { @@ -1465,7 +1490,7 @@ string base64Encode(std::string_view s) } -string base64Decode(std::string_view s) +std::string base64Decode(std::string_view s) { constexpr char npos = -1; constexpr std::array<char, 256> base64DecodeChars = [&]() { @@ -1477,7 +1502,10 @@ string base64Decode(std::string_view s) return result; }(); - string res; + 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) { @@ -1561,7 +1589,22 @@ std::pair<unsigned short, unsigned short> getWindowSize() } -static Sync<std::list<std::function<void()>>> _interruptCallbacks; +/* We keep track of interrupt callbacks using integer tokens, so we can iterate + safely without having to lock the data structure while executing arbitrary + functions. + */ +struct InterruptCallbacks { + typedef int64_t Token; + + /* We use unique tokens so that we can't accidentally delete the wrong + handler because of an erroneous double delete. */ + Token nextToken = 0; + + /* Used as a list, see InterruptCallbacks comment. */ + std::map<Token, std::function<void()>> callbacks; +}; + +static Sync<InterruptCallbacks> _interruptCallbacks; static void signalHandlerThread(sigset_t set) { @@ -1583,8 +1626,19 @@ void triggerInterrupt() _isInterrupted = true; { - auto interruptCallbacks(_interruptCallbacks.lock()); - for (auto & callback : *interruptCallbacks) { + InterruptCallbacks::Token i = 0; + while (true) { + std::function<void()> callback; + { + auto interruptCallbacks(_interruptCallbacks.lock()); + auto lb = interruptCallbacks->callbacks.lower_bound(i); + if (lb == interruptCallbacks->callbacks.end()) + break; + + callback = lb->second; + i = lb->first + 1; + } + try { callback(); } catch (...) { @@ -1638,7 +1692,9 @@ void setStackSize(size_t stackSize) #endif } +#if __linux__ static AutoCloseFD fdSavedMountNamespace; +#endif void saveMountNamespace() { @@ -1657,8 +1713,13 @@ void restoreMountNamespace() { #if __linux__ try { + auto savedCwd = absPath("."); + if (fdSavedMountNamespace && setns(fdSavedMountNamespace.get(), CLONE_NEWNS) == -1) throw SysError("restoring parent mount namespace"); + if (chdir(savedCwd.c_str()) == -1) { + throw SysError("restoring cwd"); + } } catch (Error & e) { debug(e.msg()); } @@ -1694,21 +1755,22 @@ void restoreProcessContext(bool restoreMounts) /* RAII helper to automatically deregister a callback. */ struct InterruptCallbackImpl : InterruptCallback { - std::list<std::function<void()>>::iterator it; + InterruptCallbacks::Token token; ~InterruptCallbackImpl() override { - _interruptCallbacks.lock()->erase(it); + auto interruptCallbacks(_interruptCallbacks.lock()); + interruptCallbacks->callbacks.erase(token); } }; std::unique_ptr<InterruptCallback> createInterruptCallback(std::function<void()> callback) { auto interruptCallbacks(_interruptCallbacks.lock()); - interruptCallbacks->push_back(callback); + auto token = interruptCallbacks->nextToken++; + interruptCallbacks->callbacks.emplace(token, callback); auto res = std::make_unique<InterruptCallbackImpl>(); - res->it = interruptCallbacks->end(); - res->it--; + res->token = token; return std::unique_ptr<InterruptCallback>(res.release()); } @@ -1804,7 +1866,7 @@ void connect(int fd, const std::string & path) } -string showBytes(uint64_t bytes) +std::string showBytes(uint64_t bytes) { return fmt("%.2f MiB", bytes / (1024.0 * 1024.0)); } @@ -1815,7 +1877,7 @@ void commonChildInit(Pipe & logPipe) { logger = makeSimpleLogger(); - const static string pathNullDevice = "/dev/null"; + const static std::string pathNullDevice = "/dev/null"; restoreProcessContext(false); /* Put the child in a separate session (and thus a separate |