lix/src/resolve-system-dependencies/resolve-system-dependencies.cc
2020-06-15 14:12:39 +02:00

211 lines
5.8 KiB
C++

#include "derivations.hh"
#include "globals.hh"
#include "shared.hh"
#include "store-api.hh"
#include <sys/utsname.h>
#include <algorithm>
#include <iostream>
#include <fstream>
#include <sys/mman.h>
#include <fcntl.h>
#include <mach-o/loader.h>
#include <mach-o/swap.h>
#define DO_SWAP(x, y) ((x) ? OSSwapInt32(y) : (y))
using namespace nix;
static auto cacheDir = Path{};
Path resolveCacheFile(Path lib)
{
std::replace(lib.begin(), lib.end(), '/', '%');
return cacheDir + "/" + lib;
}
std::set<string> readCacheFile(const Path & file)
{
return tokenizeString<set<string>>(readFile(file), "\n");
}
std::set<std::string> runResolver(const Path & filename)
{
AutoCloseFD fd = open(filename.c_str(), O_RDONLY);
if (!fd)
throw SysError("opening '%s'", filename);
struct stat st;
if (fstat(fd.get(), &st))
throw SysError("statting '%s'", filename);
if (!S_ISREG(st.st_mode)) {
logError({
.name = "Regular MACH file",
.hint = hintfmt("file '%s' is not a regular file", filename)
});
return {};
}
if (st.st_size < sizeof(mach_header_64)) {
logError({
.name = "File too short",
.hint = hintfmt("file '%s' is too short for a MACH binary", filename)
});
return {};
}
char* obj = (char*) mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, fd.get(), 0);
if (!obj)
throw SysError("mmapping '%s'", filename);
ptrdiff_t mach64_offset = 0;
uint32_t magic = ((mach_header_64*) obj)->magic;
if (magic == FAT_CIGAM || magic == FAT_MAGIC) {
bool should_swap = magic == FAT_CIGAM;
uint32_t narches = DO_SWAP(should_swap, ((fat_header *) obj)->nfat_arch);
for (uint32_t i = 0; i < narches; i++) {
fat_arch* arch = (fat_arch*) (obj + sizeof(fat_header) + sizeof(fat_arch) * i);
if (DO_SWAP(should_swap, arch->cputype) == CPU_TYPE_X86_64) {
mach64_offset = (ptrdiff_t) DO_SWAP(should_swap, arch->offset);
break;
}
}
if (mach64_offset == 0) {
logError({
.name = "No mach64 blobs",
.hint = hintfmt("Could not find any mach64 blobs in file '%1%', continuing...", filename)
});
return {};
}
} else if (magic == MH_MAGIC_64 || magic == MH_CIGAM_64) {
mach64_offset = 0;
} else {
logError({
.name = "Magic number",
.hint = hintfmt("Object file has unknown magic number '%1%', skipping it...", magic)
});
return {};
}
mach_header_64 * m_header = (mach_header_64 *) (obj + mach64_offset);
bool should_swap = magic == MH_CIGAM_64;
ptrdiff_t cmd_offset = mach64_offset + sizeof(mach_header_64);
std::set<string> libs;
for (uint32_t i = 0; i < DO_SWAP(should_swap, m_header->ncmds); i++) {
load_command * cmd = (load_command *) (obj + cmd_offset);
switch(DO_SWAP(should_swap, cmd->cmd)) {
case LC_LOAD_UPWARD_DYLIB:
case LC_LOAD_DYLIB:
case LC_REEXPORT_DYLIB:
libs.insert(std::string((char *) cmd + ((dylib_command*) cmd)->dylib.name.offset));
break;
}
cmd_offset += DO_SWAP(should_swap, cmd->cmdsize);
}
return libs;
}
bool isSymlink(const Path & path)
{
struct stat st;
if (lstat(path.c_str(), &st) == -1)
throw SysError("getting attributes of path '%1%'", path);
return S_ISLNK(st.st_mode);
}
Path resolveSymlink(const Path & path)
{
auto target = readLink(path);
return hasPrefix(target, "/")
? target
: dirOf(path) + "/" + target;
}
std::set<string> resolveTree(const Path & path, PathSet & deps)
{
std::set<string> results;
if (!deps.insert(path).second) return {};
for (auto & lib : runResolver(path)) {
results.insert(lib);
for (auto & p : resolveTree(lib, deps)) {
results.insert(p);
}
}
return results;
}
std::set<string> getPath(const Path & path)
{
if (hasPrefix(path, "/dev")) return {};
Path cacheFile = resolveCacheFile(path);
if (pathExists(cacheFile))
return readCacheFile(cacheFile);
std::set<string> deps, paths;
paths.insert(path);
Path nextPath(path);
while (isSymlink(nextPath)) {
nextPath = resolveSymlink(nextPath);
paths.insert(nextPath);
}
for (auto & t : resolveTree(nextPath, deps))
paths.insert(t);
writeFile(cacheFile, concatStringsSep("\n", paths));
return paths;
}
int main(int argc, char ** argv)
{
return handleExceptions(argv[0], [&]() {
initNix();
struct utsname _uname;
uname(&_uname);
auto cacheParentDir = (format("%1%/dependency-maps") % settings.nixStateDir).str();
cacheDir = (format("%1%/%2%-%3%-%4%")
% cacheParentDir
% _uname.machine
% _uname.sysname
% _uname.release).str();
mkdir(cacheParentDir.c_str(), 0755);
mkdir(cacheDir.c_str(), 0755);
auto store = openStore();
StringSet impurePaths;
if (std::string(argv[1]) == "--test")
impurePaths.insert(argv[2]);
else {
auto drv = store->derivationFromPath(store->parseStorePath(argv[1]));
impurePaths = tokenizeString<StringSet>(get(drv.env, "__impureHostDeps").value_or(""));
impurePaths.insert("/usr/lib/libSystem.dylib");
}
std::set<string> allPaths;
for (auto & path : impurePaths)
for (auto & p : getPath(path))
allPaths.insert(p);
std::cout << "extra-chroot-dirs" << std::endl;
for (auto & path : allPaths)
std::cout << path << std::endl;
std::cout << std::endl;
});
}