GCC Code Coverage Report

Directory: cvmfs/
File: cvmfs/bigqueue.h
Date: 2026-08-16 02:40:26
Exec Total Coverage
Lines: 76 77 98.7%
Branches: 23 32 71.9%
Line Branch Exec Source
1 /**
2 * This file is part of the CernVM File System.
3 *
4 * Similar to bigvector, but queue semantics. Used by the negative entry
5 * tracker. Allocates with mmap in order to avoid memory fragmentation.
6 */
7
8 #ifndef CVMFS_BIGQUEUE_H_
9 #define CVMFS_BIGQUEUE_H_
10
11 #include <algorithm>
12 #include <cassert>
13 #include <cstdlib>
14 #include <new>
15
16 #include "util/smalloc.h"
17
18 template<class Item>
19 class BigQueue {
20 public:
21 743 BigQueue() {
22 743 Alloc(kNumInit);
23 743 size_ = 0;
24 743 }
25
26 explicit BigQueue(const size_t num_items) {
27 const size_t min_items = kNumInit;
28 Alloc(std::max(num_items, min_items));
29 size_ = 0;
30 }
31
32 4 BigQueue(const BigQueue<Item> &other) { CopyFrom(other); }
33
34 106 BigQueue<Item> &operator=(const BigQueue<Item> &other) {
35
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 106 times.
 106 if (&other == this)
36 ✗ return *this;
37
38 106 Dealloc();
39 106 CopyFrom(other);
40 106 return *this;
41 }
42
43 722 ~BigQueue() { Dealloc(); }
44
45 80063396 void PushBack(const Item &item) {
46
2/2
✓ Branch 1 taken 462 times.
✓ Branch 2 taken 80062934 times.
 80063396 if (GetAvailableSpace() == 0) {
47 462 Migrate(1.9 * static_cast<float>(capacity_));
48
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 462 times.
 462 assert(GetAvailableSpace() > 0);
49 }
50
1/2
✓ Branch 2 taken 55396 times.
✗ Branch 3 not taken.
 80063396 new (head_ + size_) Item(item);
51 80063396 size_++;
52 80063396 }
53
54 80006075 void PopFront() {
55
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 80006075 times.
 80006075 assert(!IsEmpty());
56 80006075 head_++;
57 80006075 size_--;
58
4/4
✓ Branch 0 taken 80005220 times.
✓ Branch 1 taken 855 times.
✓ Branch 2 taken 204 times.
✓ Branch 3 taken 80005016 times.
 80006075 if ((size_ > kCompactThreshold) && (size_ < (capacity_ / 2)))
59 204 Migrate(static_cast<int>(static_cast<float>(capacity_ * 0.6)));
60 80006075 }
61
62 80061945 bool Peek(Item **item) {
63
2/2
✓ Branch 1 taken 291 times.
✓ Branch 2 taken 80061654 times.
 80061945 if (IsEmpty())
64 291 return false;
65 80061654 *item = head_;
66 80061654 return true;
67 }
68
69 160068020 bool IsEmpty() const { return size_ == 0; }
70
71 106 void Clear() {
72 106 Dealloc();
73 106 Alloc(kNumInit);
74 106 }
75
76 34910 size_t size() const { return size_; }
77 40 size_t capacity() const { return capacity_; }
78
79 private:
80 static const size_t kNumInit = 64;
81 static const size_t kCompactThreshold = 64;
82
83 100120779 size_t GetHeadOffset() const { return head_ - buffer_; }
84 80063858 size_t GetAvailableSpace() const {
85 80063858 return capacity_ - (size_ + GetHeadOffset());
86 }
87
88 1625 void Alloc(const size_t num_elements) {
89 1625 size_t const num_bytes = sizeof(Item) * num_elements;
90 1625 buffer_ = static_cast<Item *>(smmap(num_bytes));
91 1625 capacity_ = num_elements;
92 1625 head_ = buffer_;
93 1625 }
94
95 934 void Dealloc() {
96 934 FreeBuffer(buffer_, GetHeadOffset() + size_);
97 934 buffer_ = NULL;
98 934 head_ = NULL;
99 934 capacity_ = 0;
100 934 size_ = 0;
101 934 }
102
103 666 void Migrate(size_t new_capacity) {
104
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 666 times.
 666 assert(new_capacity > 0);
105
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 666 times.
 666 assert(new_capacity >= size_);
106
107 666 size_t const head_offset = GetHeadOffset();
108 666 Item *old_buffer = buffer_;
109
110 666 Alloc(new_capacity);
111
2/2
✓ Branch 0 taken 224240662 times.
✓ Branch 1 taken 666 times.
 224241328 for (size_t i = 0; i < size_; ++i)
112
1/2
✓ Branch 2 taken 90450 times.
✗ Branch 3 not taken.
 224240662 new (buffer_ + i) Item(old_buffer[head_offset + i]);
113
114 666 FreeBuffer(old_buffer, head_offset + size_);
115 666 }
116
117 1600 void FreeBuffer(Item *buf, const size_t nitems) {
118
2/2
✓ Branch 0 taken 324359354 times.
✓ Branch 1 taken 1600 times.
 324360954 for (size_t i = 0; i < nitems; ++i)
119 324359354 buf[i].~Item();
120
121
1/2
✓ Branch 0 taken 1600 times.
✗ Branch 1 not taken.
 1600 if (buf)
122 1600 smunmap(buf);
123 1600 }
124
125 110 void CopyFrom(const BigQueue<Item> &other) {
126 110 size_t const min_items = kNumInit;
127 110 Alloc(std::max(other.size_, min_items));
128
2/2
✓ Branch 0 taken 20055321 times.
✓ Branch 1 taken 110 times.
 20055431 for (size_t i = 0; i < other.size_; ++i) {
129
1/2
✓ Branch 3 taken 55321 times.
✗ Branch 4 not taken.
 20055321 new (buffer_ + i) Item(*(other.buffer_ + other.GetHeadOffset() + i));
130 }
131 110 size_ = other.size_;
132 110 }
133
134 Item *buffer_;
135 Item *head_;
136 size_t size_;
137 size_t capacity_;
138 };
139
140 #endif // CVMFS_BIGQUEUE_H_
141