pyrox.dev
1{
2 runCommand,
3 gitMinimal,
4 coccinelle,
5 python3,
6}:
7
8/*
9 Creates a patch that replaces every instantiation of GSettings in a C project
10 with a code that loads a GSettings schema from a hardcoded path.
11
12 This is useful so that libraries can find schemas even though Nix lacks
13 a standard location like /usr/share, where GSettings system could look for schemas.
14 The derivation is is somewhat dependency-heavy so it is best used as part of an update script.
15
16 For each schema id referenced in the source code (e.g. org.gnome.evolution),
17 a variable name such as `EVOLUTION` must be provided.
18 It will end up in the generated patch as `@EVOLUTION@` placeholder, which should be replaced at build time
19 with a path to the directory containing a `gschemas.compiled` file that includes the schema.
20
21 Arguments:
22 - `src`: source to generate the patch for.
23
24 - `schemaIdToVariableMapping`: attrset assigning schema ids to variable names.
25 All used schemas must be listed.
26
27 For example, `{ "org.gnome.evolution" = "EVOLUTION_SCHEMA_PATH"; }`
28 hardcodes looking for `org.gnome.evolution` into `@EVOLUTION_SCHEMA_PATH@`.
29
30 - `schemaExistsFunction`: name of the function that is used for checking
31 if optional schema exists. Its invocation will be replaced with TRUE
32 for known schemas.
33
34 - `patches`: A list of patches to apply before generating the patch.
35
36 Example:
37 passthru = {
38 hardcodeGsettingsPatch = makeHardcodeGsettingsPatch {
39 inherit (finalAttrs) src;
40 schemaIdToVariableMapping = {
41 ...
42 };
43 };
44
45 updateScript =
46 let
47 updateSource = ...;
48 updatePatch = _experimental-update-script-combinators.copyAttrOutputToFile "evolution-ews.hardcodeGsettingsPatch" ./hardcode-gsettings.patch;
49 in
50 _experimental-update-script-combinators.sequence [
51 updateSource
52 updatePatch
53 ];
54 };
55 }
56*/
57{
58 src,
59 patches ? [ ],
60 schemaIdToVariableMapping,
61 schemaExistsFunction ? null,
62}:
63
64runCommand "hardcode-gsettings.patch"
65 {
66 inherit src patches;
67 nativeBuildInputs = [
68 gitMinimal
69 coccinelle
70 python3 # For patch script
71 ];
72 }
73 ''
74 unpackPhase
75 cd "''${sourceRoot:-.}"
76 patchPhase
77 set -x
78 cp ${builtins.toFile "glib-schema-to-var.json" (builtins.toJSON schemaIdToVariableMapping)} ./glib-schema-to-var.json
79 cp ${builtins.toFile "glib-schema-exists-function.json" (builtins.toJSON schemaExistsFunction)} ./glib-schema-exists-function.json
80 git init
81 git add -A
82 spatch --sp-file "${./hardcode-gsettings.cocci}" --dir . --in-place
83 git diff > "$out"
84 ''