diff options
Diffstat (limited to 'pkgs/build-support/trivial-builders.nix')
| -rw-r--r-- | pkgs/build-support/trivial-builders.nix | 128 |
1 files changed, 96 insertions, 32 deletions
diff --git a/pkgs/build-support/trivial-builders.nix b/pkgs/build-support/trivial-builders.nix index e107db2db5c99..c67f5845135b3 100644 --- a/pkgs/build-support/trivial-builders.nix +++ b/pkgs/build-support/trivial-builders.nix @@ -234,17 +234,48 @@ rec { ''; /* - * Create a forest of symlinks to the files in `paths'. - * - * Examples: - * # adds symlinks of hello to current build. - * { symlinkJoin, hello }: - * symlinkJoin { name = "myhello"; paths = [ hello ]; } - * - * # adds symlinks of hello to current build and prints "links added" - * { symlinkJoin, hello }: - * symlinkJoin { name = "myhello"; paths = [ hello ]; postBuild = "echo links added"; } - */ + * 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. + * + * Examples: + * # 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 @@ -268,6 +299,60 @@ rec { ${postBuild} ''; + /* + * Quickly create a set of symlinks to derivations. + * + * This creates a simple derivation with symlinks to all inputs. + * + * entries is a list of attribute sets like + * { name = "name" ; path = "/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: runCommand name { preferLocalBuild = true; allowSubstitutes = false; } + ''mkdir -p $out + cd $out + ${lib.concatMapStrings (x: '' + mkdir -p "$(dirname ${lib.escapeShellArg x.name})" + ln -s ${lib.escapeShellArg x.path} ${lib.escapeShellArg x.name} + '') entries} + ''; + + /* + * 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); + /* * Make a package that just contains a setup hook with the given contents. @@ -315,27 +400,6 @@ rec { ''; - /* - * Quickly create a set of symlinks to derivations. - * entries is a list of attribute sets like - * { name = "name" ; path = "/nix/store/..."; } - * - * Example: - * - * # Symlinks hello path in store to current $out/hello - * linkFarm "hello" [ { name = "hello"; path = pkgs.hello; } ]; - * - */ - linkFarm = name: entries: runCommand name { preferLocalBuild = true; allowSubstitutes = false; } - ''mkdir -p $out - cd $out - ${lib.concatMapStrings (x: '' - mkdir -p "$(dirname ${lib.escapeShellArg x.name})" - ln -s ${lib.escapeShellArg x.path} ${lib.escapeShellArg x.name} - '') entries} - ''; - - /* Print an error message if the file with the specified name and * hash doesn't exist in the Nix store. This function should only * be used by non-redistributable software with an unfree license |