1 /**
2  * Copyright 2017 Google Inc.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "sysfs/util.hpp"
18 
19 #include <experimental/filesystem>
20 #include <iostream>
21 #include <string>
22 
23 /*
24  * There are two basic paths I want to support:
25  * 1. /sys/class/hwmon/hwmon0/pwm1
26  * 2. /sys/devices/platform/ahb/1e786000.pwm-tacho-controller/hwmon/<asterisk
27  * asterisk>/pwm1
28  *
29  * In this latter case, I want to fill in that gap.  Assuming because it's this
30  * path that it'll only have one directory there.
31  */
32 
33 static constexpr auto platform = "/sys/devices/platform/";
34 namespace fs = std::experimental::filesystem;
35 
36 std::string FixupPath(std::string original)
37 {
38     std::string::size_type n, x;
39 
40     /* TODO: Consider the merits of using regex for this. */
41     n = original.find("**");
42     x = original.find(platform);
43 
44     if ((n != std::string::npos) && (x != std::string::npos))
45     {
46         /* This path has some missing pieces and we support it. */
47         std::string base = original.substr(0, n);
48         std::string fldr;
49         std::string f = original.substr(n + 2, original.size() - (n + 2));
50 
51         /* Equivalent to glob and grab 0th entry. */
52         for (const auto& folder : fs::directory_iterator(base))
53         {
54             fldr = folder.path();
55             break;
56         }
57 
58         if (!fldr.length())
59         {
60             return original;
61         }
62 
63         return fldr + f;
64     }
65     else
66     {
67         /* It'll throw an exception when we use it if it's still bad. */
68         return original;
69     }
70 }
71