From 74f6d8767de13980b0e83a249633ee4a7e6fc547 Mon Sep 17 00:00:00 2001 From: Matthew Bauer Date: Tue, 4 Sep 2018 19:32:39 -0500 Subject: [PATCH] Get effective user in Nix commands MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ‘geteuid’ gives us the user that the command is being run as, including in setuid modes. By using geteuid to determind id, we can avoid the ‘sudo -i’ hack when upgrading Nix. So now, upgrading Nix on macOS is as simple as: $ sudo nix-channel --update $ sudo nix-env -u $ sudo launchctl stop org.nixos.nix-daemon $ sudo launchctl start org.nixos.nix-daemon or $ sudo systemctl restart nix-daemon --- src/libutil/util.cc | 2 +- src/nix-channel/nix-channel.cc | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/src/libutil/util.cc b/src/libutil/util.cc index 6bc64ae75..04c98dc80 100644 --- a/src/libutil/util.cc +++ b/src/libutil/util.cc @@ -468,7 +468,7 @@ static Lazy getHome2([]() { std::vector buf(16384); struct passwd pwbuf; struct passwd * pw; - if (getpwuid_r(getuid(), &pwbuf, buf.data(), buf.size(), &pw) != 0 + if (getpwuid_r(geteuid(), &pwbuf, buf.data(), buf.size(), &pw) != 0 || !pw || !pw->pw_dir || !pw->pw_dir[0]) throw Error("cannot determine user's home directory"); homeDir = pw->pw_dir; diff --git a/src/nix-channel/nix-channel.cc b/src/nix-channel/nix-channel.cc index 55ebda438..2083d3df5 100755 --- a/src/nix-channel/nix-channel.cc +++ b/src/nix-channel/nix-channel.cc @@ -169,7 +169,7 @@ int main(int argc, char ** argv) // Figure out the name of the channels profile. ; - auto pw = getpwuid(getuid()); + auto pw = getpwuid(geteuid()); std::string name = pw ? pw->pw_name : getEnv("USER", ""); if (name.empty()) throw Error("cannot figure out user name");