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#include <cerrno>
#include <algorithm>
#include <vector>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <dirent.h>
#include <fcntl.h>
#include "archive.hh"
#include "util.hh"
namespace nix {
static string archiveVersion1 = "nix-archive-1";
PathFilter defaultPathFilter;
static void dump(const string & path, Sink & sink, PathFilter & filter);
static void dumpEntries(const Path & path, Sink & sink, PathFilter & filter)
{
Strings names = readDirectory(path);
vector<string> names2(names.begin(), names.end());
sort(names2.begin(), names2.end());
for (vector<string>::iterator i = names2.begin();
i != names2.end(); ++i)
{
Path entry = path + "/" + *i;
if (filter(entry)) {
writeString("entry", sink);
writeString("(", sink);
writeString("name", sink);
writeString(*i, sink);
writeString("node", sink);
dump(entry, sink, filter);
writeString(")", sink);
}
}
}
static void dumpContents(const Path & path, unsigned int size,
Sink & sink)
{
writeString("contents", sink);
writeInt(size, sink);
AutoCloseFD fd = open(path.c_str(), O_RDONLY);
if (fd == -1) throw SysError(format("opening file `%1%'") % path);
unsigned char buf[65536];
unsigned int left = size;
while (left > 0) {
size_t n = left > sizeof(buf) ? sizeof(buf) : left;
readFull(fd, buf, n);
left -= n;
sink(buf, n);
}
writePadding(size, sink);
}
static void dump(const Path & path, Sink & sink, PathFilter & filter)
{
struct stat st;
if (lstat(path.c_str(), &st))
throw SysError(format("getting attributes of path `%1%'") % path);
writeString("(", sink);
if (S_ISREG(st.st_mode)) {
writeString("type", sink);
writeString("regular", sink);
if (st.st_mode & S_IXUSR) {
writeString("executable", sink);
writeString("", sink);
}
dumpContents(path, st.st_size, sink);
}
else if (S_ISDIR(st.st_mode)) {
writeString("type", sink);
writeString("directory", sink);
dumpEntries(path, sink, filter);
}
else if (S_ISLNK(st.st_mode)) {
writeString("type", sink);
writeString("symlink", sink);
writeString("target", sink);
writeString(readLink(path), sink);
}
else throw Error("unknown file type: " + path);
writeString(")", sink);
}
void dumpPath(const Path & path, Sink & sink, PathFilter & filter)
{
writeString(archiveVersion1, sink);
dump(path, sink, filter);
}
static Error badArchive(string s)
{
return Error("bad archive: " + s);
}
static void skipGeneric(Source & source)
{
if (readString(source) == "(") {
while (readString(source) != ")")
skipGeneric(source);
}
}
static void restore(const Path & path, Source & source);
static void restoreEntry(const Path & path, Source & source)
{
string s, name;
s = readString(source);
if (s != "(") throw badArchive("expected open tag");
while (1) {
checkInterrupt();
s = readString(source);
if (s == ")") {
break;
} else if (s == "name") {
name = readString(source);
} else if (s == "node") {
if (s == "") throw badArchive("entry name missing");
restore(path + "/" + name, source);
} else {
throw badArchive("unknown field " + s);
skipGeneric(source);
}
}
}
static void restoreContents(int fd, const Path & path, Source & source)
{
unsigned int size = readInt(source);
unsigned int left = size;
unsigned char buf[65536];
while (left) {
checkInterrupt();
unsigned int n = sizeof(buf);
if (n > left) n = left;
source(buf, n);
writeFull(fd, buf, n);
left -= n;
}
readPadding(size, source);
}
static void restore(const Path & path, Source & source)
{
string s;
s = readString(source);
if (s != "(") throw badArchive("expected open tag");
enum { tpUnknown, tpRegular, tpDirectory, tpSymlink } type = tpUnknown;
AutoCloseFD fd;
while (1) {
checkInterrupt();
s = readString(source);
if (s == ")") {
break;
}
else if (s == "type") {
if (type != tpUnknown)
throw badArchive("multiple type fields");
string t = readString(source);
if (t == "regular") {
type = tpRegular;
fd = open(path.c_str(), O_CREAT | O_EXCL | O_WRONLY, 0666);
if (fd == -1)
throw SysError("creating file " + path);
}
else if (t == "directory") {
type = tpDirectory;
if (mkdir(path.c_str(), 0777) == -1)
throw SysError("creating directory " + path);
}
else if (t == "symlink") {
type = tpSymlink;
}
else throw badArchive("unknown file type " + t);
}
else if (s == "contents" && type == tpRegular) {
restoreContents(fd, path, source);
}
else if (s == "executable" && type == tpRegular) {
readString(source);
struct stat st;
if (fstat(fd, &st) == -1)
throw SysError("fstat");
if (fchmod(fd, st.st_mode | (S_IXUSR | S_IXGRP | S_IXOTH)) == -1)
throw SysError("fchmod");
}
else if (s == "entry" && type == tpDirectory) {
restoreEntry(path, source);
}
else if (s == "target" && type == tpSymlink) {
string target = readString(source);
if (symlink(target.c_str(), path.c_str()) == -1)
throw SysError("creating symlink " + path);
}
else {
throw badArchive("unknown field " + s);
skipGeneric(source);
}
}
}
void restorePath(const Path & path, Source & source)
{
if (readString(source) != archiveVersion1)
throw badArchive("expected Nix archive");
restore(path, source);
}
}
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