GCC Code Coverage Report

Directory: cvmfs/
File: cvmfs/bigqueue.h
Date: 2026-10-18 02:40:11
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:
21 666 BigQueue() {
22 666 Alloc(kNumInit);
23 666 size_ = 0;
24 666 }
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 2 BigQueue(const BigQueue<Item> &other) { CopyFrom(other); }
33
34 22 BigQueue<Item> &operator=(const BigQueue<Item> &other) {
35
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 22 times.
 22 if (&other == this)
36 ✗ return *this;
37
38 22 Dealloc();
39 22 CopyFrom(other);
40 22 return *this;
41 }
42
43 668 ~BigQueue() { Dealloc(); }
44
45 40010202 void PushBack(const Item &item) {
46
2/2
✓ Branch 1 taken 126 times.
✓ Branch 2 taken 40010076 times.
 40010202 if (GetAvailableSpace() == 0) {
47 126 Migrate(1.9 * static_cast<float>(capacity_));
48
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 126 times.
 126 assert(GetAvailableSpace() > 0);
49 }
50
1/2
✓ Branch 2 taken 6202 times.
✗ Branch 3 not taken.
 40010202 new (head_ + size_) Item(item);
51 40010202 size_++;
52 40010202 }
53
54 40003045 void PopFront() {
55
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 40003045 times.
 40003045 assert(!IsEmpty());
56 40003045 head_++;
57 40003045 size_--;
58
4/4
✓ Branch 0 taken 40002610 times.
✓ Branch 1 taken 435 times.
✓ Branch 2 taken 102 times.
✓ Branch 3 taken 40002508 times.
 40003045 if ((size_ > kCompactThreshold) && (size_ < (capacity_ / 2)))
59 102 Migrate(static_cast<int>(static_cast<float>(capacity_ * 0.6)));
60 40003045 }
61
62 40009447 bool Peek(Item **item) {
63
2/2
✓ Branch 1 taken 145 times.
✓ Branch 2 taken 40009302 times.
 40009447 if (IsEmpty())
64 145 return false;
65 40009302 *item = head_;
66 40009302 return true;
67 }
68
69 80012492 bool IsEmpty() const { return size_ == 0; }
70
71 22 void Clear() {
72 22 Dealloc();
73 22 Alloc(kNumInit);
74 22 }
75
76 3982 size_t size() const { return size_; }
77 20 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 50017425 size_t GetHeadOffset() const { return head_ - buffer_; }
84 40010328 size_t GetAvailableSpace() const {
85 40010328 return capacity_ - (size_ + GetHeadOffset());
86 }
87
88 940 void Alloc(const size_t num_elements) {
89 940 size_t const num_bytes = sizeof(Item) * num_elements;
90 940 buffer_ = static_cast<Item *>(smmap(num_bytes));
91 940 capacity_ = num_elements;
92 940 head_ = buffer_;
93 940 }
94
95 712 void Dealloc() {
96 712 FreeBuffer(buffer_, GetHeadOffset() + size_);
97 712 buffer_ = NULL;
98 712 head_ = NULL;
99 712 capacity_ = 0;
100 712 size_ = 0;
101 712 }
102
103 228 void Migrate(size_t new_capacity) {
104
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 228 times.
 228 assert(new_capacity > 0);
105
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 228 times.
 228 assert(new_capacity >= size_);
106
107 228 size_t const head_offset = GetHeadOffset();
108 228 Item *old_buffer = buffer_;
109
110 228 Alloc(new_capacity);
111
2/2
✓ Branch 0 taken 112085156 times.
✓ Branch 1 taken 228 times.
 112085384 for (size_t i = 0; i < size_; ++i)
112
1/2
✓ Branch 2 taken 10050 times.
✗ Branch 3 not taken.
 112085156 new (buffer_ + i) Item(old_buffer[head_offset + i]);
113
114 228 FreeBuffer(old_buffer, head_offset + size_);
115 228 }
116
117 940 void FreeBuffer(Item *buf, const size_t nitems) {
118
2/2
✓ Branch 0 taken 162101515 times.
✓ Branch 1 taken 940 times.
 162102455 for (size_t i = 0; i < nitems; ++i)
119 162101515 buf[i].~Item();
120
121
1/2
✓ Branch 0 taken 940 times.
✗ Branch 1 not taken.
 940 if (buf)
122 940 smunmap(buf);
123 940 }
124
125 24 void CopyFrom(const BigQueue<Item> &other) {
126 24 size_t const min_items = kNumInit;
127 24 Alloc(std::max(other.size_, min_items));
128
2/2
✓ Branch 0 taken 10006157 times.
✓ Branch 1 taken 24 times.
 10006181 for (size_t i = 0; i < other.size_; ++i) {
129
1/2
✓ Branch 3 taken 6157 times.
✗ Branch 4 not taken.
 10006157 new (buffer_ + i) Item(*(other.buffer_ + other.GetHeadOffset() + i));
130 }
131 24 size_ = other.size_;
132 24 }
133
134 Item *buffer_;
135 Item *head_;
136 size_t size_;
137 size_t capacity_;
138 };
139
140 #endif // CVMFS_BIGQUEUE_H_
141