1// Copyright 2016 Google Inc. All rights reserved. 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15package android 16 17import ( 18 "github.com/google/blueprint" 19) 20 21// This file implements hooks that external module types can use to inject logic into existing 22// module types. Each hook takes an interface as a parameter so that new methods can be added 23// to the interface without breaking existing module types. 24 25// Load hooks are run after the module's properties have been filled from the blueprint file, but 26// before the module has been split into architecture variants, and before defaults modules have 27// been applied. 28type LoadHookContext interface { 29 // TODO: a new context that includes Config() but not Target(), etc.? 30 BaseContext 31 AppendProperties(...interface{}) 32 PrependProperties(...interface{}) 33 CreateModule(blueprint.ModuleFactory, ...interface{}) 34} 35 36// Arch hooks are run after the module has been split into architecture variants, and can be used 37// to add architecture-specific properties. 38type ArchHookContext interface { 39 BaseContext 40 AppendProperties(...interface{}) 41 PrependProperties(...interface{}) 42} 43 44func AddLoadHook(m blueprint.Module, hook func(LoadHookContext)) { 45 h := &m.(Module).base().hooks 46 h.load = append(h.load, hook) 47} 48 49func AddArchHook(m blueprint.Module, hook func(ArchHookContext)) { 50 h := &m.(Module).base().hooks 51 h.arch = append(h.arch, hook) 52} 53 54func (x *hooks) runLoadHooks(ctx LoadHookContext, m *ModuleBase) { 55 if len(x.load) > 0 { 56 for _, x := range x.load { 57 x(ctx) 58 if ctx.Failed() { 59 return 60 } 61 } 62 } 63} 64 65func (x *hooks) runArchHooks(ctx ArchHookContext, m *ModuleBase) { 66 if len(x.arch) > 0 { 67 for _, x := range x.arch { 68 x(ctx) 69 if ctx.Failed() { 70 return 71 } 72 } 73 } 74} 75 76type InstallHookContext interface { 77 ModuleContext 78 Path() OutputPath 79 Symlink() bool 80} 81 82// Install hooks are run after a module creates a rule to install a file or symlink. 83// The installed path is available from InstallHookContext.Path(), and 84// InstallHookContext.Symlink() will be true if it was a symlink. 85func AddInstallHook(m blueprint.Module, hook func(InstallHookContext)) { 86 h := &m.(Module).base().hooks 87 h.install = append(h.install, hook) 88} 89 90type installHookContext struct { 91 ModuleContext 92 path OutputPath 93 symlink bool 94} 95 96func (x *installHookContext) Path() OutputPath { 97 return x.path 98} 99 100func (x *installHookContext) Symlink() bool { 101 return x.symlink 102} 103 104func (x *hooks) runInstallHooks(ctx ModuleContext, path OutputPath, symlink bool) { 105 if len(x.install) > 0 { 106 mctx := &installHookContext{ 107 ModuleContext: ctx, 108 path: path, 109 symlink: symlink, 110 } 111 for _, x := range x.install { 112 x(mctx) 113 if mctx.Failed() { 114 return 115 } 116 } 117 } 118} 119 120type hooks struct { 121 load []func(LoadHookContext) 122 arch []func(ArchHookContext) 123 install []func(InstallHookContext) 124} 125 126func LoadHookMutator(ctx TopDownMutatorContext) { 127 if m, ok := ctx.Module().(Module); ok { 128 // Cast through *androidTopDownMutatorContext because AppendProperties is implemented 129 // on *androidTopDownMutatorContext but not exposed through TopDownMutatorContext 130 var loadHookCtx LoadHookContext = ctx.(*androidTopDownMutatorContext) 131 m.base().hooks.runLoadHooks(loadHookCtx, m.base()) 132 } 133} 134 135func archHookMutator(ctx TopDownMutatorContext) { 136 if m, ok := ctx.Module().(Module); ok { 137 // Cast through *androidTopDownMutatorContext because AppendProperties is implemented 138 // on *androidTopDownMutatorContext but not exposed through TopDownMutatorContext 139 var archHookCtx ArchHookContext = ctx.(*androidTopDownMutatorContext) 140 m.base().hooks.runArchHooks(archHookCtx, m.base()) 141 } 142} 143