nixpkgs/pkgs/build-support/trivial-builders/default.nix
Yueh-Shun Li e9fd4389d2 writeClosure: init, replacing writeReferencesToFile
Replace writeReferencesToFile with writeClosure.

Make writeClosure accept a list of paths instead of a path.

Re-implement with JSON-based exportReferencesGraph interface provided by
__structuredAttrs = true.

Reword the documentation.

Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Someone Serge <sergei.kozlukov@aalto.fi>
2024-03-19 02:45:50 +08:00

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{ lib, config, stdenv, stdenvNoCC, jq, lndir, runtimeShell, shellcheck-minimal }:
let
inherit (lib)
optionalAttrs
warn
;
in
rec {
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-runCommand
runCommand = name: env: runCommandWith {
stdenv = stdenvNoCC;
runLocal = false;
inherit name;
derivationArgs = env;
};
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-runCommandLocal
runCommandLocal = name: env: runCommandWith {
stdenv = stdenvNoCC;
runLocal = true;
inherit name;
derivationArgs = env;
};
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-runCommandCC
runCommandCC = name: env: runCommandWith {
stdenv = stdenv;
runLocal = false;
inherit name;
derivationArgs = env;
};
# `runCommandCCLocal` left out on purpose.
# We shouldnt force the user to have a cc in scope.
# TODO: Move documentation for runCommandWith to the Nixpkgs manual
/*
Generalized version of the `runCommand`-variants
which does customized behavior via a single
attribute set passed as the first argument
instead of having a lot of variants like
`runCommand*`. Additionally it allows changing
the used `stdenv` freely and has a more explicit
approach to changing the arguments passed to
`stdenv.mkDerivation`.
*/
runCommandWith =
let
# prevent infinite recursion for the default stdenv value
defaultStdenv = stdenv;
in
{
# which stdenv to use, defaults to a stdenv with a C compiler, pkgs.stdenv
stdenv ? defaultStdenv
# whether to build this derivation locally instead of substituting
, runLocal ? false
# extra arguments to pass to stdenv.mkDerivation
, derivationArgs ? { }
# name of the resulting derivation
, name
# TODO(@Artturin): enable strictDeps always
}: buildCommand:
stdenv.mkDerivation ({
enableParallelBuilding = true;
inherit buildCommand name;
passAsFile = [ "buildCommand" ]
++ (derivationArgs.passAsFile or [ ]);
}
// lib.optionalAttrs (! derivationArgs?meta) {
pos = let args = builtins.attrNames derivationArgs; in
if builtins.length args > 0
then builtins.unsafeGetAttrPos (builtins.head args) derivationArgs
else null;
}
// (lib.optionalAttrs runLocal {
preferLocalBuild = true;
allowSubstitutes = false;
})
// builtins.removeAttrs derivationArgs [ "passAsFile" ]);
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-writeTextFile
writeTextFile =
{ name
, text
, executable ? false
, destination ? ""
, checkPhase ? ""
, meta ? { }
, allowSubstitutes ? false
, preferLocalBuild ? true
, derivationArgs ? { }
}:
let
matches = builtins.match "/bin/([^/]+)" destination;
in
runCommand name
({
inherit text executable checkPhase allowSubstitutes preferLocalBuild;
passAsFile = [ "text" ]
++ derivationArgs.passAsFile or [ ];
meta = lib.optionalAttrs (executable && matches != null)
{
mainProgram = lib.head matches;
} // meta // derivationArgs.meta or {};
} // removeAttrs derivationArgs [ "passAsFile" "meta" ])
''
target=$out${lib.escapeShellArg destination}
mkdir -p "$(dirname "$target")"
if [ -e "$textPath" ]; then
mv "$textPath" "$target"
else
echo -n "$text" > "$target"
fi
if [ -n "$executable" ]; then
chmod +x "$target"
fi
eval "$checkPhase"
'';
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-text-writing
writeText = name: text: writeTextFile { inherit name text; };
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-text-writing
writeTextDir = path: text: writeTextFile {
inherit text;
name = builtins.baseNameOf path;
destination = "/${path}";
};
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-text-writing
writeScript = name: text: writeTextFile { inherit name text; executable = true; };
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-text-writing
writeScriptBin = name: text: writeTextFile {
inherit name text;
executable = true;
destination = "/bin/${name}";
};
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-text-writing
writeShellScript = name: text:
writeTextFile {
inherit name;
executable = true;
text = ''
#!${runtimeShell}
${text}
'';
checkPhase = ''
${stdenv.shellDryRun} "$target"
'';
};
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-text-writing
writeShellScriptBin = name: text:
writeTextFile {
inherit name;
executable = true;
destination = "/bin/${name}";
text = ''
#!${runtimeShell}
${text}
'';
checkPhase = ''
${stdenv.shellDryRun} "$target"
'';
meta.mainProgram = name;
};
# TODO: move parameter documentation to the Nixpkgs manual
# See doc/build-helpers/trivial-build-helpers.chapter.md
# or https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-writeShellApplication
writeShellApplication =
{
/*
The name of the script to write.
Type: String
*/
name,
/*
The shell script's text, not including a shebang.
Type: String
*/
text,
/*
Inputs to add to the shell script's `$PATH` at runtime.
Type: [String|Derivation]
*/
runtimeInputs ? [ ],
/*
Extra environment variables to set at runtime.
Type: AttrSet
*/
runtimeEnv ? null,
/*
`stdenv.mkDerivation`'s `meta` argument.
Type: AttrSet
*/
meta ? { },
/*
The `checkPhase` to run. Defaults to `shellcheck` on supported
platforms and `bash -n`.
The script path will be given as `$target` in the `checkPhase`.
Type: String
*/
checkPhase ? null,
/*
Checks to exclude when running `shellcheck`, e.g. `[ "SC2016" ]`.
See <https://www.shellcheck.net/wiki/> for a list of checks.
Type: [String]
*/
excludeShellChecks ? [ ],
/*
Bash options to activate with `set -o` at the start of the script.
Defaults to `[ "errexit" "nounset" "pipefail" ]`.
Type: [String]
*/
bashOptions ? [ "errexit" "nounset" "pipefail" ],
/* Extra arguments to pass to `stdenv.mkDerivation`.
:::{.caution}
Certain derivation attributes are used internally,
overriding those could cause problems.
:::
Type: AttrSet
*/
derivationArgs ? { },
}:
writeTextFile {
inherit name meta derivationArgs;
executable = true;
destination = "/bin/${name}";
allowSubstitutes = true;
preferLocalBuild = false;
text = ''
#!${runtimeShell}
${lib.concatMapStringsSep "\n" (option: "set -o ${option}") bashOptions}
'' + lib.optionalString (runtimeEnv != null)
(lib.concatStrings
(lib.mapAttrsToList
(name: value: ''
${lib.toShellVar name value}
export ${name}
'')
runtimeEnv))
+ lib.optionalString (runtimeInputs != [ ]) ''
export PATH="${lib.makeBinPath runtimeInputs}:$PATH"
'' + ''
${text}
'';
checkPhase =
# GHC (=> shellcheck) isn't supported on some platforms (such as risc-v)
# but we still want to use writeShellApplication on those platforms
let
shellcheckSupported = lib.meta.availableOn stdenv.buildPlatform shellcheck-minimal.compiler;
excludeOption = lib.optionalString (excludeShellChecks != [ ]) "--exclude '${lib.concatStringsSep "," excludeShellChecks}'";
shellcheckCommand = lib.optionalString shellcheckSupported ''
# use shellcheck which does not include docs
# pandoc takes long to build and documentation isn't needed for just running the cli
${lib.getExe shellcheck-minimal} ${excludeOption} "$target"
'';
in
if checkPhase == null then ''
runHook preCheck
${stdenv.shellDryRun} "$target"
${shellcheckCommand}
runHook postCheck
''
else checkPhase;
};
# Create a C binary
# TODO: add to writers? pkgs/build-support/writers
writeCBin = pname: code:
runCommandCC pname
{
inherit pname code;
executable = true;
passAsFile = [ "code" ];
# Pointless to do this on a remote machine.
preferLocalBuild = true;
allowSubstitutes = false;
meta = {
mainProgram = pname;
};
}
''
n=$out/bin/${pname}
mkdir -p "$(dirname "$n")"
mv "$codePath" code.c
$CC -x c code.c -o "$n"
'';
# TODO: deduplicate with documentation in doc/build-helpers/trivial-build-helpers.chapter.md
# see also https://github.com/NixOS/nixpkgs/pull/249721
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-concatText
/* concat a list of files to the nix store.
The contents of files are added to the file in the store.
Example:
# Writes my-file to /nix/store/<store path>
concatTextFile {
name = "my-file";
files = [ drv1 "${drv2}/path/to/file" ];
}
See also the `concatText` helper function below.
# Writes executable my-file to /nix/store/<store path>/bin/my-file
concatTextFile {
name = "my-file";
files = [ drv1 "${drv2}/path/to/file" ];
executable = true;
destination = "/bin/my-file";
}
*/
concatTextFile =
{ name # the name of the derivation
, files
, executable ? false # run chmod +x ?
, destination ? "" # relative path appended to $out eg "/bin/foo"
, checkPhase ? "" # syntax checks, e.g. for scripts
, meta ? { }
}:
runCommandLocal name
{ inherit files executable checkPhase meta destination; }
''
file=$out$destination
mkdir -p "$(dirname "$file")"
cat $files > "$file"
if [ -n "$executable" ]; then
chmod +x "$file"
fi
eval "$checkPhase"
'';
# TODO: deduplicate with documentation in doc/build-helpers/trivial-build-helpers.chapter.md
# see also https://github.com/NixOS/nixpkgs/pull/249721
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-concatText
/*
Writes a text file to nix store with no optional parameters available.
Example:
# Writes contents of files to /nix/store/<store path>
concatText "my-file" [ file1 file2 ]
*/
concatText = name: files: concatTextFile { inherit name files; };
# TODO: deduplicate with documentation in doc/build-helpers/trivial-build-helpers.chapter.md
# see also https://github.com/NixOS/nixpkgs/pull/249721
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-concatText
/*
Writes a text file to nix store with and mark it as executable.
Example:
# Writes contents of files to /nix/store/<store path>
concatScript "my-file" [ file1 file2 ]
*/
concatScript = name: files: concatTextFile { inherit name files; executable = true; };
/*
TODO: Deduplicate this documentation.
More docs in doc/build-helpers/trivial-build-helpers.chapter.md
See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-symlinkJoin
Create a forest of symlinks to the files in `paths`.
This creates a single derivation that replicates the directory structure
of all the input paths.
BEWARE: it may not "work right" when the passed paths contain symlinks to directories.
Example:
# adds symlinks of hello to current build.
symlinkJoin { name = "myhello"; paths = [ pkgs.hello ]; }
# adds symlinks of hello and stack to current build and prints "links added"
symlinkJoin { name = "myexample"; paths = [ pkgs.hello pkgs.stack ]; postBuild = "echo links added"; }
This creates a derivation with a directory structure like the following:
/nix/store/sglsr5g079a5235hy29da3mq3hv8sjmm-myexample
|-- bin
| |-- hello -> /nix/store/qy93dp4a3rqyn2mz63fbxjg228hffwyw-hello-2.10/bin/hello
| `-- stack -> /nix/store/6lzdpxshx78281vy056lbk553ijsdr44-stack-2.1.3.1/bin/stack
`-- share
|-- bash-completion
| `-- completions
| `-- stack -> /nix/store/6lzdpxshx78281vy056lbk553ijsdr44-stack-2.1.3.1/share/bash-completion/completions/stack
|-- fish
| `-- vendor_completions.d
| `-- stack.fish -> /nix/store/6lzdpxshx78281vy056lbk553ijsdr44-stack-2.1.3.1/share/fish/vendor_completions.d/stack.fish
...
symlinkJoin and linkFarm are similar functions, but they output
derivations with different structure.
symlinkJoin is used to create a derivation with a familiar directory
structure (top-level bin/, share/, etc), but with all actual files being symlinks to
the files in the input derivations.
symlinkJoin is used many places in nixpkgs to create a single derivation
that appears to contain binaries, libraries, documentation, etc from
multiple input derivations.
linkFarm is instead used to create a simple derivation with symlinks to
other derivations. A derivation created with linkFarm is often used in CI
as a easy way to build multiple derivations at once.
*/
symlinkJoin =
args_@{ name
, paths
, preferLocalBuild ? true
, allowSubstitutes ? false
, postBuild ? ""
, ...
}:
let
args = removeAttrs args_ [ "name" "postBuild" ]
// {
inherit preferLocalBuild allowSubstitutes;
passAsFile = [ "paths" ];
}; # pass the defaults
in
runCommand name args
''
mkdir -p $out
for i in $(cat $pathsPath); do
${lndir}/bin/lndir -silent $i $out
done
${postBuild}
'';
# TODO: move linkFarm docs to the Nixpkgs manual
/*
Quickly create a set of symlinks to derivations.
This creates a simple derivation with symlinks to all inputs.
entries can be a list of attribute sets like
[ { name = "name" ; path = "/nix/store/..."; } ]
or an attribute set name -> path like:
{ name = "/nix/store/..."; other = "/nix/store/..."; }
Example:
# Symlinks hello and stack paths in store to current $out/hello-test and
# $out/foobar.
linkFarm "myexample" [ { name = "hello-test"; path = pkgs.hello; } { name = "foobar"; path = pkgs.stack; } ]
This creates a derivation with a directory structure like the following:
/nix/store/qc5728m4sa344mbks99r3q05mymwm4rw-myexample
|-- foobar -> /nix/store/6lzdpxshx78281vy056lbk553ijsdr44-stack-2.1.3.1
`-- hello-test -> /nix/store/qy93dp4a3rqyn2mz63fbxjg228hffwyw-hello-2.10
See the note on symlinkJoin for the difference between linkFarm and symlinkJoin.
*/
linkFarm = name: entries:
let
entries' =
if (lib.isAttrs entries) then entries
# We do this foldl to have last-wins semantics in case of repeated entries
else if (lib.isList entries) then lib.foldl (a: b: a // { "${b.name}" = b.path; }) { } entries
else throw "linkFarm entries must be either attrs or a list!";
linkCommands = lib.mapAttrsToList
(name: path: ''
mkdir -p "$(dirname ${lib.escapeShellArg "${name}"})"
ln -s ${lib.escapeShellArg "${path}"} ${lib.escapeShellArg "${name}"}
'')
entries';
in
runCommand name
{
preferLocalBuild = true;
allowSubstitutes = false;
passthru.entries = entries';
} ''
mkdir -p $out
cd $out
${lib.concatStrings linkCommands}
'';
# TODO: move linkFarmFromDrvs docs to the Nixpkgs manual
/*
Easily create a linkFarm from a set of derivations.
This calls linkFarm with a list of entries created from the list of input
derivations. It turns each input derivation into an attribute set
like { name = drv.name ; path = drv }, and passes this to linkFarm.
Example:
# Symlinks the hello, gcc, and ghc derivations in $out
linkFarmFromDrvs "myexample" [ pkgs.hello pkgs.gcc pkgs.ghc ]
This creates a derivation with a directory structure like the following:
/nix/store/m3s6wkjy9c3wy830201bqsb91nk2yj8c-myexample
|-- gcc-wrapper-9.2.0 -> /nix/store/fqhjxf9ii4w4gqcsx59fyw2vvj91486a-gcc-wrapper-9.2.0
|-- ghc-8.6.5 -> /nix/store/gnf3s07bglhbbk4y6m76sbh42siym0s6-ghc-8.6.5
`-- hello-2.10 -> /nix/store/k0ll91c4npk4lg8lqhx00glg2m735g74-hello-2.10
*/
linkFarmFromDrvs = name: drvs:
let mkEntryFromDrv = drv: { name = drv.name; path = drv; };
in linkFarm name (map mkEntryFromDrv drvs);
# TODO: move onlyBin docs to the Nixpkgs manual
/*
Produce a derivation that links to the target derivation's `/bin`,
and *only* `/bin`.
This is useful when your favourite package doesn't have a separate
bin output and other contents of the package's output (e.g. setup
hooks) cause trouble when used in your environment.
*/
onlyBin = drv: runCommand "${drv.name}-only-bin" { } ''
mkdir -p $out
ln -s ${lib.getBin drv}/bin $out/bin
'';
# Docs in doc/builders/special/makesetuphook.section.md
# See https://nixos.org/manual/nixpkgs/unstable/#sec-pkgs.makeSetupHook
makeSetupHook =
{ name ? lib.warn "calling makeSetupHook without passing a name is deprecated." "hook"
, deps ? [ ]
# hooks go in nativeBuildInput so these will be nativeBuildInput
, propagatedBuildInputs ? [ ]
# these will be buildInputs
, depsTargetTargetPropagated ? [ ]
, meta ? { }
, passthru ? { }
, substitutions ? { }
}:
script:
runCommand name
(substitutions // {
# TODO(@Artturin:) substitutions should be inside the env attrset
# but users are likely passing non-substitution arguments through substitutions
# turn off __structuredAttrs to unbreak substituteAll
__structuredAttrs = false;
inherit meta;
inherit depsTargetTargetPropagated;
propagatedBuildInputs =
# remove list conditionals before 23.11
lib.warnIf (!lib.isList deps) "'deps' argument to makeSetupHook must be a list. content of deps: ${toString deps}"
(lib.warnIf (deps != [ ]) "'deps' argument to makeSetupHook is deprecated and will be removed in release 23.11., Please use propagatedBuildInputs instead. content of deps: ${toString deps}"
propagatedBuildInputs ++ (if lib.isList deps then deps else [ deps ]));
strictDeps = true;
# TODO 2023-01, no backport: simplify to inherit passthru;
passthru = passthru
// optionalAttrs (substitutions?passthru)
(warn "makeSetupHook (name = ${lib.strings.escapeNixString name}): `substitutions.passthru` is deprecated. Please set `passthru` directly."
substitutions.passthru);
})
(''
mkdir -p $out/nix-support
cp ${script} $out/nix-support/setup-hook
recordPropagatedDependencies
'' + lib.optionalString (substitutions != { }) ''
substituteAll ${script} $out/nix-support/setup-hook
'');
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-writeReferencesToFile
# TODO: Convert to throw after Nixpkgs 24.05 branch-off.
writeReferencesToFile = (if config.allowAliases then lib.warn else throw)
"writeReferencesToFile is deprecated in favour of writeClosure"
(path: writeClosure [ path ]);
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-writeClosure
writeClosure = paths: runCommand "runtime-deps"
{
# Get the cleaner exportReferencesGraph interface
__structuredAttrs = true;
exportReferencesGraph.graph = paths;
nativeBuildInputs = [ jq ];
}
''
jq -r ".graph | map(.path) | sort | .[]" "$NIX_ATTRS_JSON_FILE" > "$out"
'';
# Docs in doc/build-helpers/trivial-build-helpers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#trivial-builder-writeDirectReferencesToFile
writeDirectReferencesToFile = path: runCommand "runtime-references"
{
exportReferencesGraph = [ "graph" path ];
inherit path;
}
''
touch ./references
while read p; do
read dummy
read nrRefs
if [[ $p == $path ]]; then
for ((i = 0; i < nrRefs; i++)); do
read ref;
echo $ref >>./references
done
else
for ((i = 0; i < nrRefs; i++)); do
read ref;
done
fi
done < graph
sort ./references >$out
'';
# TODO: move writeStringReferencesToFile docs to the Nixpkgs manual
/*
Extract a string's references to derivations and paths (its
context) and write them to a text file, removing the input string
itself from the dependency graph. This is useful when you want to
make a derivation depend on the string's references, but not its
contents (to avoid unnecessary rebuilds, for example).
Note that this only works as intended on Nix >= 2.3.
*/
writeStringReferencesToFile = string:
/*
The basic operation this performs is to copy the string context
from `string` to a second string and wrap that string in a
derivation. However, that alone is not enough, since nothing in the
string refers to the output paths of the derivations/paths in its
context, meaning they'll be considered build-time dependencies and
removed from the wrapper derivation's closure. Putting the
necessary output paths in the new string is however not very
straightforward - the attrset returned by `getContext` contains
only references to derivations' .drv-paths, not their output
paths. In order to "convert" them, we try to extract the
corresponding paths from the original string using regex.
*/
let
# Taken from https://github.com/NixOS/nix/blob/130284b8508dad3c70e8160b15f3d62042fc730a/src/libutil/hash.cc#L84
nixHashChars = "0123456789abcdfghijklmnpqrsvwxyz";
context = builtins.getContext string;
derivations = lib.filterAttrs (n: v: v ? outputs) context;
# Objects copied from outside of the store, such as paths and
# `builtins.fetch*`ed ones
sources = lib.attrNames (lib.filterAttrs (n: v: v ? path) context);
packages =
lib.mapAttrs'
(name: value:
{
inherit value;
name = lib.head (builtins.match "${builtins.storeDir}/[${nixHashChars}]+-(.*)\.drv" name);
})
derivations;
# The syntax of output paths differs between outputs named `out`
# and other, explicitly named ones. For explicitly named ones,
# the output name is suffixed as `-name`, but `out` outputs
# aren't suffixed at all, and thus aren't easily distinguished
# from named output paths. Therefore, we find all the named ones
# first so we can use them to remove false matches when looking
# for `out` outputs (see the definition of `outputPaths`).
namedOutputPaths =
lib.flatten
(lib.mapAttrsToList
(name: value:
(map
(output:
lib.filter
lib.isList
(builtins.split "(${builtins.storeDir}/[${nixHashChars}]+-${name}-${output})" string))
(lib.remove "out" value.outputs)))
packages);
# Only `out` outputs
outputPaths =
lib.flatten
(lib.mapAttrsToList
(name: value:
if lib.elem "out" value.outputs then
lib.filter
(x: lib.isList x &&
# If the matched path is in `namedOutputPaths`,
# it's a partial match of an output path where
# the output name isn't `out`
lib.all (o: !lib.hasPrefix (lib.head x) o) namedOutputPaths)
(builtins.split "(${builtins.storeDir}/[${nixHashChars}]+-${name})" string)
else
[ ])
packages);
allPaths = lib.concatStringsSep "\n" (lib.unique (sources ++ namedOutputPaths ++ outputPaths));
allPathsWithContext = builtins.appendContext allPaths context;
in
if builtins ? getContext then
writeText "string-references" allPathsWithContext
else
writeDirectReferencesToFile (writeText "string-file" string);
# Docs in doc/build-helpers/fetchers.chapter.md
# See https://nixos.org/manual/nixpkgs/unstable/#requirefile
requireFile =
{ name ? null
, sha256 ? null
, sha1 ? null
, hash ? null
, url ? null
, message ? null
, hashMode ? "flat"
}:
assert (message != null) || (url != null);
assert (sha256 != null) || (sha1 != null) || (hash != null);
assert (name != null) || (url != null);
let
msg =
if message != null then message
else ''
Unfortunately, we cannot download file ${name_} automatically.
Please go to ${url} to download it yourself, and add it to the Nix store
using either
nix-store --add-fixed ${hashAlgo} ${name_}
or
nix-prefetch-url --type ${hashAlgo} file:///path/to/${name_}
'';
hashAlgo =
if hash != null then (builtins.head (lib.strings.splitString "-" hash))
else if sha256 != null then "sha256"
else "sha1";
hashAlgo_ = if hash != null then "" else hashAlgo;
hash_ =
if hash != null then hash
else if sha256 != null then sha256
else sha1;
name_ = if name == null then baseNameOf (toString url) else name;
in
stdenvNoCC.mkDerivation {
name = name_;
outputHashMode = hashMode;
outputHashAlgo = hashAlgo_;
outputHash = hash_;
preferLocalBuild = true;
allowSubstitutes = false;
builder = writeScript "restrict-message" ''
source ${stdenvNoCC}/setup
cat <<_EOF_
***
${msg}
***
_EOF_
exit 1
'';
};
# TODO: move copyPathToStore docs to the Nixpkgs manual
/*
Copy a path to the Nix store.
Nix automatically copies files to the store before stringifying paths.
If you need the store path of a file, ${copyPathToStore <path>} can be
shortened to ${<path>}.
*/
copyPathToStore = builtins.filterSource (p: t: true);
# TODO: move copyPathsToStore docs to the Nixpkgs manual
/*
Copy a list of paths to the Nix store.
*/
copyPathsToStore = builtins.map copyPathToStore;
# TODO: move applyPatches docs to the Nixpkgs manual
/* Applies a list of patches to a source directory.
Example:
# Patching nixpkgs:
applyPatches {
src = pkgs.path;
patches = [
(pkgs.fetchpatch {
url = "https://github.com/NixOS/nixpkgs/commit/1f770d20550a413e508e081ddc08464e9d08ba3d.patch";
sha256 = "1nlzx171y3r3jbk0qhvnl711kmdk57jlq4na8f8bs8wz2pbffymr";
})
];
}
*/
applyPatches =
{ src
, name ? (if builtins.typeOf src == "path"
then builtins.baseNameOf src
else
if builtins.isAttrs src && builtins.hasAttr "name" src
then src.name
else throw "applyPatches: please supply a `name` argument because a default name can only be computed when the `src` is a path or is an attribute set with a `name` attribute."
) + "-patched"
, patches ? [ ]
, prePatch ? ""
, postPatch ? ""
, ...
}@args:
if patches == [ ] && prePatch == "" && postPatch == ""
then src # nothing to do, so use original src to avoid additional drv
else stdenvNoCC.mkDerivation
({
inherit name src patches prePatch postPatch;
preferLocalBuild = true;
allowSubstitutes = false;
phases = "unpackPhase patchPhase installPhase";
installPhase = "cp -R ./ $out";
}
# Carry `meta` information from the underlying `src` if present.
// (optionalAttrs (src?meta) { inherit (src) meta; })
// (removeAttrs args [ "src" "name" "patches" "prePatch" "postPatch" ]));
# TODO: move docs to Nixpkgs manual
/* An immutable file in the store with a length of 0 bytes. */
emptyFile = runCommand "empty-file"
{
outputHashAlgo = "sha256";
outputHashMode = "recursive";
outputHash = "0ip26j2h11n1kgkz36rl4akv694yz65hr72q4kv4b3lxcbi65b3p";
preferLocalBuild = true;
} "touch $out";
# TODO: move docs to Nixpkgs manual
/* An immutable empty directory in the store. */
emptyDirectory = runCommand "empty-directory"
{
outputHashAlgo = "sha256";
outputHashMode = "recursive";
outputHash = "0sjjj9z1dhilhpc8pq4154czrb79z9cm044jvn75kxcjv6v5l2m5";
preferLocalBuild = true;
} "mkdir $out";
}