-
Notifications
You must be signed in to change notification settings - Fork 0
/
scan.cc
executable file
·109 lines (92 loc) · 3.54 KB
/
scan.cc
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
#include <fstream>
#include <iostream>
#include <stdlib.h>
#include <string.h>
#include "library.h"
int main(int argc, char** argv) {
if (argc < 3) {
std::cout << "Error, usage must be:\n";
std::cout << "./scan <heapfile> <page_size>\n";
return 1;
}
int page_size = atoi(argv[2]);
FILE *heapfile = fopen(argv[1], "rb");
if (!heapfile)
{
std::cout << "Error, could not find file " << argv[1] << "\n";
return 1;
}
Heapfile *heap = new Heapfile();
heap->page_size = page_size;
heap->file_ptr = heapfile;
int num_pages_in_directory = number_of_pages_per_directory_page(page_size);
int next_directory_offset = 0;
fread(&next_directory_offset, sizeof(int), 1, heapfile);
int page_offset = 0;
int freespace = 0;
int current_directory_position = 0;
Page page;
while (next_directory_offset != 0) {
for (int i = 0; i < num_pages_in_directory; ++i) {
fread(&page_offset, sizeof(int), 1, heapfile);
fread(&freespace, sizeof(int), 1, heapfile);
if (freespace != page_size) {
// jump to page
current_directory_position = ftell(heapfile);
read_page(heap, page_offset, &page);
for (int j = 0; j < fixed_len_page_capacity(&page); ++j) {
Record r = page.data->at(j);
bool empty_record = true;
for (Record::iterator it = r.begin(); it != r.end(); ++it) {
if (strlen(*it) > 0) {
empty_record = false;
std::cout << *it;
if (it + 1 != r.end()) {
std::cout << ",";
}
}
}
if (!empty_record) {
std::cout << "\n";
}
}
// return to directory location
fseek(heapfile, current_directory_position, SEEK_SET);
}
}
}
// one more time for last directory
current_directory_position = ftell(heapfile);
fseek(heapfile, 0, SEEK_END);
if (ftell(heapfile) - (current_directory_position + page_size) >= 0) {
fseek(heapfile, current_directory_position, SEEK_SET);
for (int i = 0; i < num_pages_in_directory; ++i) {
fread(&page_offset, sizeof(int), 1, heapfile);
fread(&freespace, sizeof(int), 1, heapfile);
if (freespace != page_size) {
// jump to page
current_directory_position = ftell(heapfile);
read_page(heap, page_offset, &page);
for (int j = 0; j < fixed_len_page_capacity(&page); ++j) {
Record r = page.data->at(j);
bool empty_record = true;
for (Record::iterator it = r.begin(); it != r.end(); ++it) {
if (strlen(*it) > 0) {
empty_record = false;
std::cout << *it;
if (it + 1 != r.end()) {
std::cout << ",";
}
}
}
if (!empty_record) {
std::cout << "\n";
}
}
// return to directory location
fseek(heapfile, current_directory_position, SEEK_SET);
}
}
}
return 0;
}