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-rw-r--r--src/libutil/error.hh10
-rw-r--r--src/libutil/filesystem.cc172
-rw-r--r--src/libutil/json.cc27
-rw-r--r--src/libutil/json.hh11
-rw-r--r--src/libutil/serialise.cc20
-rw-r--r--src/libutil/serialise.hh4
-rw-r--r--src/libutil/tests/json.cc4
-rw-r--r--src/libutil/util.cc151
-rw-r--r--src/libutil/util.hh14
9 files changed, 272 insertions, 141 deletions
diff --git a/src/libutil/error.hh b/src/libutil/error.hh
index a53e9802e..3d1479c54 100644
--- a/src/libutil/error.hh
+++ b/src/libutil/error.hh
@@ -204,13 +204,19 @@ public:
int errNo;
template<typename... Args>
- SysError(const Args & ... args)
+ SysError(int errNo_, const Args & ... args)
: Error("")
{
- errNo = errno;
+ errNo = errNo_;
auto hf = hintfmt(args...);
err.msg = hintfmt("%1%: %2%", normaltxt(hf.str()), strerror(errNo));
}
+
+ template<typename... Args>
+ SysError(const Args & ... args)
+ : SysError(errno, args ...)
+ {
+ }
};
}
diff --git a/src/libutil/filesystem.cc b/src/libutil/filesystem.cc
new file mode 100644
index 000000000..403389e60
--- /dev/null
+++ b/src/libutil/filesystem.cc
@@ -0,0 +1,172 @@
+#include <sys/time.h>
+#include <filesystem>
+
+#include "finally.hh"
+#include "util.hh"
+#include "types.hh"
+
+namespace fs = std::filesystem;
+
+namespace nix {
+
+static Path tempName(Path tmpRoot, const Path & prefix, bool includePid,
+ int & counter)
+{
+ tmpRoot = canonPath(tmpRoot.empty() ? getEnv("TMPDIR").value_or("/tmp") : tmpRoot, true);
+ if (includePid)
+ return (format("%1%/%2%-%3%-%4%") % tmpRoot % prefix % getpid() % counter++).str();
+ else
+ return (format("%1%/%2%-%3%") % tmpRoot % prefix % counter++).str();
+}
+
+Path createTempDir(const Path & tmpRoot, const Path & prefix,
+ bool includePid, bool useGlobalCounter, mode_t mode)
+{
+ static int globalCounter = 0;
+ int localCounter = 0;
+ int & counter(useGlobalCounter ? globalCounter : localCounter);
+
+ while (1) {
+ checkInterrupt();
+ Path tmpDir = tempName(tmpRoot, prefix, includePid, counter);
+ if (mkdir(tmpDir.c_str(), mode) == 0) {
+#if __FreeBSD__
+ /* Explicitly set the group of the directory. This is to
+ work around around problems caused by BSD's group
+ ownership semantics (directories inherit the group of
+ the parent). For instance, the group of /tmp on
+ FreeBSD is "wheel", so all directories created in /tmp
+ will be owned by "wheel"; but if the user is not in
+ "wheel", then "tar" will fail to unpack archives that
+ have the setgid bit set on directories. */
+ if (chown(tmpDir.c_str(), (uid_t) -1, getegid()) != 0)
+ throw SysError("setting group of directory '%1%'", tmpDir);
+#endif
+ return tmpDir;
+ }
+ if (errno != EEXIST)
+ throw SysError("creating directory '%1%'", tmpDir);
+ }
+}
+
+
+std::pair<AutoCloseFD, Path> createTempFile(const Path & prefix)
+{
+ Path tmpl(getEnv("TMPDIR").value_or("/tmp") + "/" + prefix + ".XXXXXX");
+ // Strictly speaking, this is UB, but who cares...
+ // FIXME: use O_TMPFILE.
+ AutoCloseFD fd(mkstemp((char *) tmpl.c_str()));
+ if (!fd)
+ throw SysError("creating temporary file '%s'", tmpl);
+ closeOnExec(fd.get());
+ return {std::move(fd), tmpl};
+}
+
+void createSymlink(const Path & target, const Path & link,
+ std::optional<time_t> mtime)
+{
+ if (symlink(target.c_str(), link.c_str()))
+ throw SysError("creating symlink from '%1%' to '%2%'", link, target);
+ if (mtime) {
+ struct timeval times[2];
+ times[0].tv_sec = *mtime;
+ times[0].tv_usec = 0;
+ times[1].tv_sec = *mtime;
+ times[1].tv_usec = 0;
+ if (lutimes(link.c_str(), times))
+ throw SysError("setting time of symlink '%s'", link);
+ }
+}
+
+void replaceSymlink(const Path & target, const Path & link,
+ std::optional<time_t> mtime)
+{
+ for (unsigned int n = 0; true; n++) {
+ Path tmp = canonPath(fmt("%s/.%d_%s", dirOf(link), n, baseNameOf(link)));
+
+ try {
+ createSymlink(target, tmp, mtime);
+ } catch (SysError & e) {
+ if (e.errNo == EEXIST) continue;
+ throw;
+ }
+
+ renameFile(tmp, link);
+
+ break;
+ }
+}
+
+void setWriteTime(const fs::path & p, const struct stat & st)
+{
+ struct timeval times[2];
+ times[0] = {
+ .tv_sec = st.st_atime,
+ .tv_usec = 0,
+ };
+ times[1] = {
+ .tv_sec = st.st_mtime,
+ .tv_usec = 0,
+ };
+ if (lutimes(p.c_str(), times) != 0)
+ throw SysError("changing modification time of '%s'", p);
+}
+
+void copy(const fs::directory_entry & from, const fs::path & to, bool andDelete)
+{
+ // TODO: Rewrite the `is_*` to use `symlink_status()`
+ auto statOfFrom = lstat(from.path().c_str());
+ auto fromStatus = from.symlink_status();
+
+ // Mark the directory as writable so that we can delete its children
+ if (andDelete && fs::is_directory(fromStatus)) {
+ fs::permissions(from.path(), fs::perms::owner_write, fs::perm_options::add | fs::perm_options::nofollow);
+ }
+
+
+ if (fs::is_symlink(fromStatus) || fs::is_regular_file(fromStatus)) {
+ fs::copy(from.path(), to, fs::copy_options::copy_symlinks | fs::copy_options::overwrite_existing);
+ } else if (fs::is_directory(fromStatus)) {
+ fs::create_directory(to);
+ for (auto & entry : fs::directory_iterator(from.path())) {
+ copy(entry, to / entry.path().filename(), andDelete);
+ }
+ } else {
+ throw Error("file '%s' has an unsupported type", from.path());
+ }
+
+ setWriteTime(to, statOfFrom);
+ if (andDelete) {
+ if (!fs::is_symlink(fromStatus))
+ fs::permissions(from.path(), fs::perms::owner_write, fs::perm_options::add | fs::perm_options::nofollow);
+ fs::remove(from.path());
+ }
+}
+
+void renameFile(const Path & oldName, const Path & newName)
+{
+ fs::rename(oldName, newName);
+}
+
+void moveFile(const Path & oldName, const Path & newName)
+{
+ try {
+ renameFile(oldName, newName);
+ } catch (fs::filesystem_error & e) {
+ auto oldPath = fs::path(oldName);
+ auto newPath = fs::path(newName);
+ // For the move to be as atomic as possible, copy to a temporary
+ // directory
+ fs::path temp = createTempDir(newPath.parent_path(), "rename-tmp");
+ Finally removeTemp = [&]() { fs::remove(temp); };
+ auto tempCopyTarget = temp / "copy-target";
+ if (e.code().value() == EXDEV) {
+ fs::remove(newPath);
+ warn("Can’t rename %s as %s, copying instead", oldName, newName);
+ copy(fs::directory_entry(oldPath), tempCopyTarget, true);
+ renameFile(tempCopyTarget, newPath);
+ }
+ }
+}
+
+}
diff --git a/src/libutil/json.cc b/src/libutil/json.cc
index b0a5d7e75..2f9e97ff5 100644
--- a/src/libutil/json.cc
+++ b/src/libutil/json.cc
@@ -6,7 +6,8 @@
namespace nix {
-void toJSON(std::ostream & str, const char * start, const char * end)
+template<>
+void toJSON<std::string_view>(std::ostream & str, const std::string_view & s)
{
constexpr size_t BUF_SIZE = 4096;
char buf[BUF_SIZE + 7]; // BUF_SIZE + largest single sequence of puts
@@ -21,7 +22,7 @@ void toJSON(std::ostream & str, const char * start, const char * end)
};
put('"');
- for (auto i = start; i != end; i++) {
+ for (auto i = s.begin(); i != s.end(); i++) {
if (bufPos >= BUF_SIZE) flush();
if (*i == '\"' || *i == '\\') { put('\\'); put(*i); }
else if (*i == '\n') { put('\\'); put('n'); }
@@ -44,7 +45,7 @@ void toJSON(std::ostream & str, const char * start, const char * end)
void toJSON(std::ostream & str, const char * s)
{
- if (!s) str << "null"; else toJSON(str, s, s + strlen(s));
+ if (!s) str << "null"; else toJSON(str, std::string_view(s));
}
template<> void toJSON<int>(std::ostream & str, const int & n) { str << n; }
@@ -55,11 +56,7 @@ template<> void toJSON<long long>(std::ostream & str, const long long & n) { str
template<> void toJSON<unsigned long long>(std::ostream & str, const unsigned long long & n) { str << n; }
template<> void toJSON<float>(std::ostream & str, const float & n) { str << n; }
template<> void toJSON<double>(std::ostream & str, const double & n) { str << n; }
-
-template<> void toJSON<std::string>(std::ostream & str, const std::string & s)
-{
- toJSON(str, s.c_str(), s.c_str() + s.size());
-}
+template<> void toJSON<std::string>(std::ostream & str, const std::string & s) { toJSON(str, (std::string_view) s); }
template<> void toJSON<bool>(std::ostream & str, const bool & b)
{
@@ -154,7 +151,7 @@ JSONObject::~JSONObject()
}
}
-void JSONObject::attr(const std::string & s)
+void JSONObject::attr(std::string_view s)
{
comma();
toJSON(state->str, s);
@@ -162,19 +159,19 @@ void JSONObject::attr(const std::string & s)
if (state->indent) state->str << ' ';
}
-JSONList JSONObject::list(const std::string & name)
+JSONList JSONObject::list(std::string_view name)
{
attr(name);
return JSONList(state);
}
-JSONObject JSONObject::object(const std::string & name)
+JSONObject JSONObject::object(std::string_view name)
{
attr(name);
return JSONObject(state);
}
-JSONPlaceholder JSONObject::placeholder(const std::string & name)
+JSONPlaceholder JSONObject::placeholder(std::string_view name)
{
attr(name);
return JSONPlaceholder(state);
@@ -196,7 +193,11 @@ JSONObject JSONPlaceholder::object()
JSONPlaceholder::~JSONPlaceholder()
{
- assert(!first || std::uncaught_exceptions());
+ if (first) {
+ assert(std::uncaught_exceptions());
+ if (state->stack != 0)
+ write(nullptr);
+ }
}
}
diff --git a/src/libutil/json.hh b/src/libutil/json.hh
index 83213ca66..3790b1a2e 100644
--- a/src/libutil/json.hh
+++ b/src/libutil/json.hh
@@ -6,7 +6,6 @@
namespace nix {
-void toJSON(std::ostream & str, const char * start, const char * end);
void toJSON(std::ostream & str, const char * s);
template<typename T>
@@ -107,7 +106,7 @@ private:
open();
}
- void attr(const std::string & s);
+ void attr(std::string_view s);
public:
@@ -128,18 +127,18 @@ public:
~JSONObject();
template<typename T>
- JSONObject & attr(const std::string & name, const T & v)
+ JSONObject & attr(std::string_view name, const T & v)
{
attr(name);
toJSON(state->str, v);
return *this;
}
- JSONList list(const std::string & name);
+ JSONList list(std::string_view name);
- JSONObject object(const std::string & name);
+ JSONObject object(std::string_view name);
- JSONPlaceholder placeholder(const std::string & name);
+ JSONPlaceholder placeholder(std::string_view name);
};
class JSONPlaceholder : JSONWriter
diff --git a/src/libutil/serialise.cc b/src/libutil/serialise.cc
index 8ff904583..2c3597775 100644
--- a/src/libutil/serialise.cc
+++ b/src/libutil/serialise.cc
@@ -48,24 +48,9 @@ FdSink::~FdSink()
}
-size_t threshold = 256 * 1024 * 1024;
-
-static void warnLargeDump()
-{
- warn("dumping very large path (> 256 MiB); this may run out of memory");
-}
-
-
void FdSink::write(std::string_view data)
{
written += data.size();
- static bool warned = false;
- if (warn && !warned) {
- if (written > threshold) {
- warnLargeDump();
- warned = true;
- }
- }
try {
writeFull(fd, data);
} catch (SysError & e) {
@@ -448,11 +433,6 @@ Error readError(Source & source)
void StringSink::operator () (std::string_view data)
{
- static bool warned = false;
- if (!warned && s.size() > threshold) {
- warnLargeDump();
- warned = true;
- }
s.append(data);
}
diff --git a/src/libutil/serialise.hh b/src/libutil/serialise.hh
index 13da26c6a..84847835a 100644
--- a/src/libutil/serialise.hh
+++ b/src/libutil/serialise.hh
@@ -97,19 +97,17 @@ protected:
struct FdSink : BufferedSink
{
int fd;
- bool warn = false;
size_t written = 0;
FdSink() : fd(-1) { }
FdSink(int fd) : fd(fd) { }
FdSink(FdSink&&) = default;
- FdSink& operator=(FdSink && s)
+ FdSink & operator=(FdSink && s)
{
flush();
fd = s.fd;
s.fd = -1;
- warn = s.warn;
written = s.written;
return *this;
}
diff --git a/src/libutil/tests/json.cc b/src/libutil/tests/json.cc
index dea73f53a..156286999 100644
--- a/src/libutil/tests/json.cc
+++ b/src/libutil/tests/json.cc
@@ -102,8 +102,8 @@ namespace nix {
TEST(toJSON, substringEscape) {
std::stringstream out;
- const char *s = "foo\t";
- toJSON(out, s+3, s + strlen(s));
+ std::string_view s = "foo\t";
+ toJSON(out, s.substr(3));
ASSERT_EQ(out.str(), "\"\\t\"");
}
diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index 28df30fef..96ac11ea2 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -35,6 +35,9 @@
#ifdef __linux__
#include <sys/prctl.h>
#include <sys/resource.h>
+
+#include <mntent.h>
+#include <cmath>
#endif
@@ -505,61 +508,6 @@ void deletePath(const Path & path, uint64_t & bytesFreed)
}
-static Path tempName(Path tmpRoot, const Path & prefix, bool includePid,
- int & counter)
-{
- tmpRoot = canonPath(tmpRoot.empty() ? getEnv("TMPDIR").value_or("/tmp") : tmpRoot, true);
- if (includePid)
- return (format("%1%/%2%-%3%-%4%") % tmpRoot % prefix % getpid() % counter++).str();
- else
- return (format("%1%/%2%-%3%") % tmpRoot % prefix % counter++).str();
-}
-
-
-Path createTempDir(const Path & tmpRoot, const Path & prefix,
- bool includePid, bool useGlobalCounter, mode_t mode)
-{
- static int globalCounter = 0;
- int localCounter = 0;
- int & counter(useGlobalCounter ? globalCounter : localCounter);
-
- while (1) {
- checkInterrupt();
- Path tmpDir = tempName(tmpRoot, prefix, includePid, counter);
- if (mkdir(tmpDir.c_str(), mode) == 0) {
-#if __FreeBSD__
- /* Explicitly set the group of the directory. This is to
- work around around problems caused by BSD's group
- ownership semantics (directories inherit the group of
- the parent). For instance, the group of /tmp on
- FreeBSD is "wheel", so all directories created in /tmp
- will be owned by "wheel"; but if the user is not in
- "wheel", then "tar" will fail to unpack archives that
- have the setgid bit set on directories. */
- if (chown(tmpDir.c_str(), (uid_t) -1, getegid()) != 0)
- throw SysError("setting group of directory '%1%'", tmpDir);
-#endif
- return tmpDir;
- }
- if (errno != EEXIST)
- throw SysError("creating directory '%1%'", tmpDir);
- }
-}
-
-
-std::pair<AutoCloseFD, Path> createTempFile(const Path & prefix)
-{
- Path tmpl(getEnv("TMPDIR").value_or("/tmp") + "/" + prefix + ".XXXXXX");
- // Strictly speaking, this is UB, but who cares...
- // FIXME: use O_TMPFILE.
- AutoCloseFD fd(mkstemp((char *) tmpl.c_str()));
- if (!fd)
- throw SysError("creating temporary file '%s'", tmpl);
- closeOnExec(fd.get());
- return {std::move(fd), tmpl};
-}
-
-
std::string getUserName()
{
auto pw = getpwuid(geteuid());
@@ -574,6 +522,7 @@ Path getHome()
{
static Path homeDir = []()
{
+ std::optional<std::string> unownedUserHomeDir = {};
auto homeDir = getEnv("HOME");
if (homeDir) {
// Only use $HOME if doesn't exist or is owned by the current user.
@@ -585,8 +534,7 @@ Path getHome()
homeDir.reset();
}
} else if (st.st_uid != geteuid()) {
- warn("$HOME ('%s') is not owned by you, falling back to the one defined in the 'passwd' file", *homeDir);
- homeDir.reset();
+ unownedUserHomeDir.swap(homeDir);
}
}
if (!homeDir) {
@@ -597,6 +545,9 @@ Path getHome()
|| !pw || !pw->pw_dir || !pw->pw_dir[0])
throw Error("cannot determine user's home directory");
homeDir = pw->pw_dir;
+ if (unownedUserHomeDir.has_value() && unownedUserHomeDir != homeDir) {
+ warn("$HOME ('%s') is not owned by you, falling back to the one defined in the 'passwd' file ('%s')", *unownedUserHomeDir, *homeDir);
+ }
}
return *homeDir;
}();
@@ -678,44 +629,6 @@ Paths createDirs(const Path & path)
}
-void createSymlink(const Path & target, const Path & link,
- std::optional<time_t> mtime)
-{
- if (symlink(target.c_str(), link.c_str()))
- throw SysError("creating symlink from '%1%' to '%2%'", link, target);
- if (mtime) {
- struct timeval times[2];
- times[0].tv_sec = *mtime;
- times[0].tv_usec = 0;
- times[1].tv_sec = *mtime;
- times[1].tv_usec = 0;
- if (lutimes(link.c_str(), times))
- throw SysError("setting time of symlink '%s'", link);
- }
-}
-
-
-void replaceSymlink(const Path & target, const Path & link,
- std::optional<time_t> mtime)
-{
- for (unsigned int n = 0; true; n++) {
- Path tmp = canonPath(fmt("%s/.%d_%s", dirOf(link), n, baseNameOf(link)));
-
- try {
- createSymlink(target, tmp, mtime);
- } catch (SysError & e) {
- if (e.errNo == EEXIST) continue;
- throw;
- }
-
- if (rename(tmp.c_str(), link.c_str()) != 0)
- throw SysError("renaming '%1%' to '%2%'", tmp, link);
-
- break;
- }
-}
-
-
void readFull(int fd, char * buf, size_t count)
{
while (count) {
@@ -788,7 +701,55 @@ void drainFD(int fd, Sink & sink, bool block)
}
}
+//////////////////////////////////////////////////////////////////////
+
+unsigned int getMaxCPU()
+{
+ #if __linux__
+ try {
+ FILE *fp = fopen("/proc/mounts", "r");
+ if (!fp)
+ return 0;
+
+ Strings cgPathParts;
+ struct mntent *ent;
+ while ((ent = getmntent(fp))) {
+ std::string mountType, mountPath;
+
+ mountType = ent->mnt_type;
+ mountPath = ent->mnt_dir;
+
+ if (mountType == "cgroup2") {
+ cgPathParts.push_back(mountPath);
+ break;
+ }
+ }
+
+ fclose(fp);
+
+ if (cgPathParts.size() > 0 && pathExists("/proc/self/cgroup")) {
+ std::string currentCgroup = readFile("/proc/self/cgroup");
+ Strings cgValues = tokenizeString<Strings>(currentCgroup, ":");
+ cgPathParts.push_back(trim(cgValues.back(), "\n"));
+ cgPathParts.push_back("cpu.max");
+ std::string fullCgPath = canonPath(concatStringsSep("/", cgPathParts));
+
+ if (pathExists(fullCgPath)) {
+ std::string cpuMax = readFile(fullCgPath);
+ std::vector<std::string> cpuMaxParts = tokenizeString<std::vector<std::string>>(cpuMax, " ");
+ std::string quota = cpuMaxParts[0];
+ std::string period = trim(cpuMaxParts[1], "\n");
+
+ if (quota != "max")
+ return std::ceil(std::stoi(quota) / std::stof(period));
+ }
+ }
+ } catch (Error &) { ignoreException(); }
+ #endif
+
+ return 0;
+}
//////////////////////////////////////////////////////////////////////
diff --git a/src/libutil/util.hh b/src/libutil/util.hh
index d3ed15b0b..cd83f250f 100644
--- a/src/libutil/util.hh
+++ b/src/libutil/util.hh
@@ -168,6 +168,17 @@ void createSymlink(const Path & target, const Path & link,
void replaceSymlink(const Path & target, const Path & link,
std::optional<time_t> mtime = {});
+void renameFile(const Path & src, const Path & dst);
+
+/**
+ * Similar to 'renameFile', but fallback to a copy+remove if `src` and `dst`
+ * are on a different filesystem.
+ *
+ * Beware that this might not be atomic because of the copy that happens behind
+ * the scenes
+ */
+void moveFile(const Path & src, const Path & dst);
+
/* Wrappers arount read()/write() that read/write exactly the
requested number of bytes. */
@@ -182,6 +193,9 @@ std::string drainFD(int fd, bool block = true, const size_t reserveSize=0);
void drainFD(int fd, Sink & sink, bool block = true);
+/* If cgroups are active, attempt to calculate the number of CPUs available.
+ If cgroups are unavailable or if cpu.max is set to "max", return 0. */
+unsigned int getMaxCPU();
/* Automatic cleanup of resources. */
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-23 14:27:38 +0000