1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
/*
* FreeRTOS memory safety proofs with CBMC.
* Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* http://aws.amazon.com/freertos
* http://www.FreeRTOS.org
*/
#include "cbmc.h"
/*
* We allocate a TCB and set some members to basic values
*/
TaskHandle_t xUnconstrainedTCB( void )
{
TCB_t * pxTCB = pvPortMalloc(sizeof(TCB_t));
uint8_t ucStaticAllocationFlag;
if ( pxTCB == NULL )
return NULL;
__CPROVER_assume( pxTCB->uxPriority < configMAX_PRIORITIES );
vListInitialiseItem( &( pxTCB->xStateListItem ) );
vListInitialiseItem( &( pxTCB->xEventListItem ) );
listSET_LIST_ITEM_OWNER( &( pxTCB->xStateListItem ), pxTCB );
listSET_LIST_ITEM_OWNER( &( pxTCB->xEventListItem ), pxTCB );
if ( nondet_bool() )
{
listSET_LIST_ITEM_VALUE( &( pxTCB->xStateListItem ), pxTCB->uxPriority );
}
else
{
listSET_LIST_ITEM_VALUE( &( pxTCB->xStateListItem ), portMAX_DELAY );
}
if ( nondet_bool() )
{
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), ( TickType_t ) configMAX_PRIORITIES - ( TickType_t ) pxTCB->uxPriority );
}
else
{
listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), portMAX_DELAY );
}
pxTCB->pxStack = ( StackType_t * ) pvPortMalloc( ( ( ( size_t ) STACK_DEPTH ) * sizeof( StackType_t ) ) );
if ( pxTCB->pxStack == NULL )
{
vPortFree( pxTCB );
return NULL;
}
__CPROVER_assume( ucStaticAllocationFlag <= tskSTATICALLY_ALLOCATED_STACK_AND_TCB );
__CPROVER_assume( ucStaticAllocationFlag >= tskDYNAMICALLY_ALLOCATED_STACK_AND_TCB );
pxTCB->ucStaticallyAllocated = ucStaticAllocationFlag;
return pxTCB;
}
/*
* We set the values of relevant global
* variables to nondeterministic values
*/
void vSetGlobalVariables()
{
xSchedulerRunning = nondet_basetype();
}
/*
* We initialise and fill the task lists so coverage is optimal.
* This initialization is not guaranteed to be minimal, but it
* is quite efficient and it serves the same purpose
*/
BaseType_t xPrepareTaskLists( TaskHandle_t * xTask )
{
TCB_t * pxTCB = NULL;
__CPROVER_assert_zero_allocation();
prvInitialiseTaskLists();
/*
* The task handle passed to TaskDelete can be NULL. In that case, the
* task to delete is the one in `pxCurrentTCB`, see the macro `prvGetTCBFromHandle`
* in line 1165 (tasks.c) for reference. For that reason, we provide a similar
* initialization for an arbitrary task `pxTCB` and `pxCurrentTCB`.
*/
pxTCB = xUnconstrainedTCB();
if ( pxTCB != NULL )
{
if ( nondet_bool() )
{
TCB_t * pxOtherTCB;
pxOtherTCB = xUnconstrainedTCB();
/*
* Nondeterministic insertion of another TCB in the same list
* to guarantee coverage in line 1174 (tasks.c)
*/
if ( pxOtherTCB != NULL )
{
vListInsert( &xPendingReadyList, &( pxOtherTCB->xStateListItem ) );
}
}
vListInsert( &xPendingReadyList, &( pxTCB->xStateListItem ) );
/*
* Nondeterministic insertion of an event list item to guarantee
* coverage in lines 1180-1184 (tasks.c)
*/
if ( nondet_bool() )
{
vListInsert( pxDelayedTaskList, &( pxTCB->xEventListItem ) );
}
}
/* Note that `*xTask = NULL` can happen here, but this is fine -- `pxCurrentTCB` will be used instead */
*xTask = pxTCB;
/*
* `pxCurrentTCB` must be initialized the same way as the previous task, but an
* allocation failure cannot happen in this case (i.e., if the previous task is NULL)
*/
pxCurrentTCB = xUnconstrainedTCB();
if ( pxCurrentTCB == NULL )
{
return pdFAIL;
}
if ( nondet_bool() )
{
TCB_t * pxOtherTCB;
pxOtherTCB = xUnconstrainedTCB();
if ( pxOtherTCB != NULL )
{
vListInsert( &pxReadyTasksLists[ pxOtherTCB->uxPriority ], &( pxOtherTCB->xStateListItem ) );
}
}
vListInsert( &pxReadyTasksLists[ pxCurrentTCB->uxPriority ], &( pxCurrentTCB->xStateListItem ) );
/* Use of this macro ensures coverage on line 185 (list.c) */
listGET_OWNER_OF_NEXT_ENTRY( pxCurrentTCB , &pxReadyTasksLists[ pxCurrentTCB->uxPriority ] );
if ( nondet_bool() )
{
vListInsert( pxDelayedTaskList, &( pxCurrentTCB->xEventListItem ) );
}
return pdPASS;
}
|
