1 /****************************************************************************
2 * Copyright (C) 2014-2015 Intel Corporation. All Rights Reserved.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * 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
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * @file knobs_init.h
24 *
25 * @brief Dynamic Knobs Initialization for Core.
26 *
27 ******************************************************************************/
28 #pragma once
29
30 #include <core/knobs.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <ctype.h>
34 #include <stdio.h>
35
36 // Assume the type is compatible with a 32-bit integer
37 template <typename T>
ConvertEnvToKnob(const char * pOverride,T & knobValue)38 static inline void ConvertEnvToKnob(const char* pOverride, T& knobValue)
39 {
40 uint32_t value = 0;
41 char* pStopped = nullptr;
42 value = strtoul(pOverride, &pStopped, 0);
43 if (pStopped != pOverride)
44 {
45 knobValue = static_cast<T>(value);
46 }
47 }
48
ConvertEnvToKnob(const char * pOverride,bool & knobValue)49 static inline void ConvertEnvToKnob(const char* pOverride, bool& knobValue)
50 {
51 size_t len = strlen(pOverride);
52 if (len == 1)
53 {
54 auto c = tolower(pOverride[0]);
55 if (c == 'y' || c == 't' || c == '1')
56 {
57 knobValue = true;
58 return;
59 }
60 if (c == 'n' || c == 'f' || c == '0')
61 {
62 knobValue = false;
63 return;
64 }
65 }
66
67 // Try converting to a number and casting to bool
68 uint32_t value = 0;
69 char* pStopped = nullptr;
70 value = strtoul(pOverride, &pStopped, 0);
71 if (pStopped != pOverride)
72 {
73 knobValue = value != 0;
74 }
75 }
76
ConvertEnvToKnob(const char * pOverride,float & knobValue)77 static inline void ConvertEnvToKnob(const char* pOverride, float& knobValue)
78 {
79 float value = knobValue;
80 if (sscanf(pOverride, "%f", &value))
81 {
82 knobValue = value;
83 }
84 }
85
ConvertEnvToKnob(const char * pOverride,std::string & knobValue)86 static inline void ConvertEnvToKnob(const char* pOverride, std::string& knobValue)
87 {
88 knobValue = pOverride;
89 }
90
91 template <typename T>
InitKnob(T & knob)92 static inline void InitKnob(T& knob)
93 {
94
95 // TODO, read registry first
96
97 // Second, read environment variables
98 const char* pOverride = getenv(knob.Name());
99
100 if (pOverride)
101 {
102 auto knobValue = knob.Value();
103 ConvertEnvToKnob(pOverride, knobValue);
104 knob.Value(knobValue);
105 }
106 }
107