For text files it is possible to do it like so:
`builtins.hashString "sha256" (builtins.readFile /tmp/a)`
but that doesn't work for binary files.
With builtins.hashFile any kind of file can be conveniently hashed.
To determine which seccomp filters to install, we were incorrectly
using settings.thisSystem, which doesn't denote the actual system when
--system is used.
Fixes#2791.
Thus
$ nix dev-shell
will now build the 'provides.devShell' attribute from the flake in the
current directory. If it doesn't exist, it falls back to
'provides.defaultPackage'.
'nix dev-shell' is intended to replace nix-shell. It supports flakes,
e.g.
$ nix dev-shell nixpkgs:hello
starts a bash shell providing an environment for building 'hello'.
Like Lorri (and unlike nix-shell), it computes the build environment
by building a modified top-level derivation that writes the
environment after running $stdenv/setup to $out and exits. This
provides some caching, so it's faster than nix-shell in some cases
(especially for packages with lots of dependencies, where the setup
script takes a long time).
There also is a command 'nix print-dev-env' that prints out shell code
for setting up the build environment in an existing shell, e.g.
$ . <(nix print-dev-env nixpkgs:hello)
https://github.com/tweag/nix/issues/21
Example:
$ nix flake info dwarffs
ID: dwarffs
URI: github:edolstra/dwarffs/a83d182fe3fe528ed6366a5cec3458bcb1a5f6e1
Description: A filesystem that fetches DWARF debug info from the Internet on demand
Revision: a83d182fe3fe528ed6366a5cec3458bcb1a5f6e1
Path: /nix/store/grgd14kxxk8q4n503j87mpz48gcqpqw7-source
This ensures that the lock file is updated *before* evaluating it, and
that it gets updated for any nix command, not just 'nix build'.
Also, while computing the lock file, allow arbitrary registry lookups,
not just at top-level.
Also, improve some error messages slightly.
Also allow "." as an installable to refer to the flake in the current
directory. E.g.
$ nix build .
will build 'provides.defaultPackage' in the flake in the current
directory.
Unlike file://<path>, this allows the path to be a dirty Git tree, so
nix build /path/to/flake:attr
is a convenient way to test building a local flake.
The general syntax for an installable is now
<flakeref>:<attrpath>. The attrpath is relative to the flake's
'provides.packages' or 'provides' if the former doesn't yield a
result. E.g.
$ nix build nixpkgs:hello
is equivalent to
$ nix build nixpkgs:packages.hello
Also, '<flakeref>:' can be omitted, in which case it defaults to
'nixpkgs', e.g.
$ nix build hello
Scanning of /proc/<pid>/{exe,cwd} was broken because '{memory:' was
prepended twice. Also, get rid of the whole '{memory:...}' thing
because it's unnecessary, we can just list the file in /proc directly.
This new structure makes more sense as there may be many sources rooting
the same store path. Many profiles can reference the same path but this
is even more true with /proc/<pid>/maps where distinct pids can and
often do map the same store path.
This implementation is also more efficient as the `Roots` map contains
only one entry per rooted store path.
It could happen that the local builder match the system but lacks some features.
Now it results a failure.
The fix gracefully excludes the local builder from the set of available builders for derivation which requires the feature, so the derivation is built on remote builders only (as though it has incompatible system, like ```aarch64-linux``` when local is x86)
This allows using an arbitrary "provides" attribute from the specified
flake. For example:
nix build --flake nixpkgs packages.hello
(Maybe provides.packages should be used for consistency...)
We want to encourage a brave new world of hermetic evaluation for
source-level reproducibility, so flakes should not poke around in the
filesystem outside of their explicit dependencies.
Note that the default installation source remains impure in that it
can refer to mutable flakes, so "nix build nixpkgs.hello" still works
(and fetches the latest nixpkgs, unless it has been pinned by the
user).
A problem with pure evaluation is that builtins.currentSystem is
unavailable. For the moment, I've hard-coded "x86_64-linux" in the
nixpkgs flake. Eventually, "system" should be a flake function
argument.
For example, github:edolstra/dwarffs is more-or-less equivalent to
https://github.com/edolstra/dwarffs.git. It's a much faster way to get
GitHub repositories: it fetches tarballs rather than entire Git
repositories. It also allows fetching specific revisions by hash
without specifying a ref (e.g. a branch name):
github:edolstra/dwarffs/41c0c1bf292ea3ac3858ff393b49ca1123dbd553
This reverts commit a0ef21262f. This
doesn't work in 'nix run' and nix-shell because setns() fails in
multithreaded programs, and Boehm GC mark threads are uncancellable.
Fixes#2646.
Inside a derivation, exportReferencesGraph already provides a way to
dump the Nix database for a specific closure. On the command line,
--dump-db gave us the same information, but only for the entire Nix
database at once.
With this change, one can now pass a list of paths to --dump-db to get
the Nix database dumped for just those paths. (The user is responsible
for ensuring this is a closure, like for --export).
Among other things, this is useful for deploying a closure to a new
host without using --import/--export; one can use tar to transfer the
store paths, and --dump-db/--load-db to transfer the validity
information. This is useful if the new host doesn't actually have Nix
yet, and the closure that is being deployed itself contains Nix.
Previously, plain derivation paths in the string context (e.g. those
that arose from builtins.storePath on a drv file, not those that arose
from accessing .drvPath of a derivation) were treated somewhat like
derivaiton paths derived from .drvPath, except their dependencies
weren't recursively added to the input set. With this change, such
plain derivation paths are simply treated as paths and added to the
source inputs set accordingly, simplifying context handling code and
removing the inconsistency. If drvPath-like behavior is desired, the
.drv file can be imported and then .drvPath can be accessed.
This is a backwards-incompatibility, but storePath is never used on
drv files within nixpkgs and almost never used elsewhere.
Trying to fetch refs that are not in refs/heads currently fails because
it looks for refs/heads/refs/foo instead of refs/foo.
eg.
builtins.fetchGit {
url = https://github.com/NixOS/nixpkgs.git;
ref = "refs/pull/1024/head;
}
SRI hashes (https://www.w3.org/TR/SRI/) combine the hash algorithm and
a base-64 hash. This allows more concise and standard hash
specifications. For example, instead of
import <nix/fetchurl.nl> {
url = https://nixos.org/releases/nix/nix-2.1.3/nix-2.1.3.tar.xz;
sha256 = "5d22dad058d5c800d65a115f919da22938c50dd6ba98c5e3a183172d149840a4";
};
you can write
import <nix/fetchurl.nl> {
url = https://nixos.org/releases/nix/nix-2.1.3/nix-2.1.3.tar.xz;
hash = "sha256-XSLa0FjVyADWWhFfkZ2iKTjFDda6mMXjoYMXLRSYQKQ=";
};
In fixed-output derivations, the outputHashAlgo is no longer mandatory
if outputHash specifies the hash (either as an SRI or in the old
"<type>:<hash>" format).
'nix hash-{file,path}' now print hashes in SRI format by default. I
also reverted them to use SHA-256 by default because that's what we're
using most of the time in Nixpkgs.
Suggested by @zimbatm.
Use the same output ordering and format everywhere.
This is such a common issue that we trade the single-line error message for
more readability.
Old message:
```
fixed-output derivation produced path '/nix/store/d4nw9x2sy9q3r32f3g5l5h1k833c01vq-example.com' with sha256 hash '08y4734bm2zahw75b16bcmcg587vvyvh0n11gwiyir70divwp1rm' instead of the expected hash '1xzwnipjd54wl8g93vpw6hxnpmdabq0wqywriiwmh7x8k0lvpq5m'
```
New message:
```
hash mismatch in fixed-output derivation '/nix/store/d4nw9x2sy9q3r32f3g5l5h1k833c01vq-example.com':
wanted: sha256:1xzwnipjd54wl8g93vpw6hxnpmdabq0wqywriiwmh7x8k0lvpq5m
got: sha256:08y4734bm2zahw75b16bcmcg587vvyvh0n11gwiyir70divwp1rm
```
Without this information the content addressable state and hashes are
lost after the first request, this causes signatures to be required for
everything even tho the path could be verified without signing.
This enables using for http for S3 request for debugging or
implementations that don't have https configured. This is not a problem
for binary caches since they should not contain sensitive information.
Both package signatures and AWS auth already protect against tampering.
The goal is to support libeditline AND libreadline and let the user
decide at compile time which one to use.
Add a compile time option to use libreadline instead of
libeditline. If compiled against libreadline completion functionality
is lost because of a incompatibility between libeditlines and
libreadlines completion function. Completion with libreadline is
possible and can be added later.
To use libreadline instead of libeditline the environment
variables 'EDITLINE_LIBS' and 'EDITLINE_CFLAGS' have to been set
during the ./configure step.
Example:
EDITLINE_LIBS="/usr/lib/x86_64-linux-gnu/libhistory.so /usr/lib/x86_64-linux-gnu/libreadline.so"
EDITLINE_CFLAGS="-DREADLINE"
The reason for this change is that for example on Debian already three
different editline libraries exist but none of those is compatible the
flavor used by nix. My hope is that with this change it would be
easier to port nix to systems that have already libreadline available.
