dxx.app.workbench source code

1 /**
2 Copyright: 2018 Mark Fisher
3 
4 License:
5 Permission is hereby granted, free of charge, to any person obtaining a copy of
6 this software and associated documentation files (the "Software"), to deal in
7 the Software without restriction, including without limitation the rights to
8 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
9 of the Software, and to permit persons to whom the Software is furnished to do
10 so, subject to the following conditions:
11 
12 The above copyright notice and this permission notice shall be included in all
13 copies or substantial portions of the Software.
14 
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 SOFTWARE.
22 **/
23 module dxx.app.workbench;
24 
25 private import std.exception;
26 
27 /* private import hunt.cache; */
28 
29 private import dxx.util;
30 
31 private import dxx.app.resource.workspace;
32 private import dxx.app.job;
33 private import dxx.app.platform;
34 
35 /++
36 The Workbench provides a framework for synchronizing job access to
37 platform resources.
38 
39 Only one single workbench job can run over a particular
40 workbench. The `waitLock` method blocks until the previous job has
41 terminated.  The `lock` method throws an exception if the previous job
42 has not terminated.
43 
44 The idea is that we don't have to worry about serializing access to the
45 underlying resources (for example, the Workspace). We can create
46 instances of WorkbenchJob and execute these in a thread pool - the
47 workbench ensures that no conflicts occur.
48 +/
49 interface Workbench {
50     static Workbench getCurrent() {
51         return resolveInjector!Workbench("app.workbench");
52     }
53     //Workbench getWorkbench();
54     void lock(shared(WorkbenchJob)) shared;
55     void unlock(shared(WorkbenchJob)) shared;
56     void waitLock(shared(WorkbenchJob)) shared;
57     bool isLocked() shared;
58 }
59 
60 final class WorkbenchDefault :
61               SyncNotificationSource, Workbench {
62     /* UCache resourceCache;
63     this() {
64         resourceCache = UCache.CreateUCache();
65     } */
66     shared(WorkbenchJob)* currentJob;
67     shared
68     void lock(shared(WorkbenchJob) j) {
69       enforce(this.currentJob is null);
70       this.currentJob = &j;
71     }
72     shared
73     void unlock(shared(WorkbenchJob) j) {
74       enforce(this.currentJob == &j);
75       this.currentJob = null;
76     }
77     shared
78     void waitLock(shared(WorkbenchJob) j) {
79       while(currentJob !is null) {
80         JobBase.join(*currentJob);
81       }
82       lock(j);
83     }
84     shared
85     bool isLocked() {
86       return (currentJob is null);
87     }
88 }
89 
90 class WorkbenchJob : PlatformJobBase {
91   override shared
92   void processPlatformJob() {
93     workbench.waitLock(this);
94     scope(exit)workbench.unlock(this);
95     processWorkbenchJob;
96   }
97   override
98   void setup() shared {
99     DXXPlatform.clearLocalCache;
100     super.setup;
101   }
102   abstract shared
103   void processWorkbenchJob();
104 }
105 
106 class WorkbenchJobDefault : WorkbenchJob {
107   Job job;
108   shared this(shared(Job) j) {
109     enforce(cast(WorkbenchJob)j is null);
110     this.job = j;
111   }
112   override shared
113   void processWorkbenchJob() {
114     job.execute;
115   }
116 }