connect(): Propagate errno from the child process

This is necessary on macOS since addTempRoot() relies on errno.
This commit is contained in:
Eelco Dolstra 2024-01-16 15:23:46 +01:00
parent 0b1d93d2ba
commit d005bade7f

View file

@ -1,6 +1,7 @@
#include "file-system.hh"
#include "processes.hh"
#include "unix-domain-socket.hh"
#include "util.hh"
#include <sys/socket.h>
#include <sys/un.h>
@ -75,21 +76,35 @@ void connect(int fd, const std::string & path)
addr.sun_family = AF_UNIX;
if (path.size() + 1 >= sizeof(addr.sun_path)) {
Pipe pipe;
pipe.create();
Pid pid = startProcess([&]() {
Path dir = dirOf(path);
if (chdir(dir.c_str()) == -1)
throw SysError("chdir to '%s' failed", dir);
std::string base(baseNameOf(path));
if (base.size() + 1 >= sizeof(addr.sun_path))
throw Error("socket path '%s' is too long", base);
memcpy(addr.sun_path, base.c_str(), base.size() + 1);
if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1)
throw SysError("cannot connect to socket at '%s'", path);
_exit(0);
try {
pipe.readSide.close();
Path dir = dirOf(path);
if (chdir(dir.c_str()) == -1)
throw SysError("chdir to '%s' failed", dir);
std::string base(baseNameOf(path));
if (base.size() + 1 >= sizeof(addr.sun_path))
throw Error("socket path '%s' is too long", base);
memcpy(addr.sun_path, base.c_str(), base.size() + 1);
if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1)
throw SysError("cannot connect to socket at '%s'", path);
writeFull(pipe.writeSide.get(), "0\n");
} catch (SysError & e) {
writeFull(pipe.writeSide.get(), fmt("%d\n", e.errNo));
} catch (...) {
writeFull(pipe.writeSide.get(), "-1\n");
}
});
int status = pid.wait();
if (status != 0)
pipe.writeSide.close();
auto errNo = string2Int<int>(chomp(drainFD(pipe.readSide.get())));
if (!errNo || *errNo == -1)
throw Error("cannot connect to socket at '%s'", path);
else if (*errNo > 0) {
errno = *errNo;
throw SysError("cannot connect to socket at '%s'", path);
}
} else {
memcpy(addr.sun_path, path.c_str(), path.size() + 1);
if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1)