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
|
#include "fs.h"
#include "ata.h"
#include "string.h"
#include "memory.h"
#include "heap.h"
#define FS_WALKER(X) bool (X)(str filename, u64 lba, usize fsize, usize fsect, void *varg)
void fs_walk(FS_WALKER(*fun), void *arg)
{
u64 lba = (*(u32 *) (0x1000-10-8))/512;
for (;;) {
u8 *info = ata_read_full(lba, 1);
if (memcmp(info+257, "ustar", 5) != 0) {
kfree(info);
break;
}
u64 fsize;
str_parse_num((str) { 11, (char *) info+124 }, 8, &fsize);
usize fsect = (fsize+511)/512;
str filename = str_intro((char *) info);
bool done = fun(filename, lba, fsize, fsect, arg);
kfree(info);
if (done)
break;
lba += 1 + fsect;
}
}
typedef struct {
str path;
str result;
} fs_read_arg;
static FS_WALKER(fs_read_walker)
{
fs_read_arg *arg = varg;
if (str_cmp(filename, arg->path) != 0)
return false;
arg->result = (str) { .len = fsize, .data = ata_read_full(lba+1, fsect) };
return true;
}
str fs_read(str path)
{
fs_read_arg arg = {
.path = path,
.result = NILS,
};
fs_walk(&fs_read_walker, &arg);
return arg.result;
}
typedef struct {
str path;
usize cap;
dir result;
} fs_readdir_arg;
static str strip_trail(str x)
{
while (x.len > 0 && x.data[x.len-1] == '/')
x.len--;
return x;
}
static FS_WALKER(fs_readdir_walker)
{
(void) lba, (void) fsect;
fs_readdir_arg *arg = varg;
enum {
HER_SELF,
HER_CHILD,
HER_GRANDCHILD,
} heritage;
str entn;
str iter = filename;
bool match = str_start(iter, arg->path);
if (!match)
return false;
iter = str_advance(iter, arg->path.len);
if (iter.len == 0) {
entn = filename;
heritage = HER_SELF;
} else {
if (arg->path.len != 0) {
if (iter.data[0] != '/')
return false;
iter = str_advance(iter, 1);
}
if (iter.len == 0) {
entn = strip_trail(filename);
heritage = HER_SELF;
} else {
entn = str_walk(&iter, S("/"));
if (iter.len == 0)
heritage = HER_CHILD;
else
heritage = HER_GRANDCHILD;
}
}
bool is_dir = filename.len == 0 || filename.data[filename.len-1] == '/';
switch (heritage) {
case HER_SELF:
if (is_dir)
return false;
__attribute__((fallthrough));
case HER_CHILD:
if (arg->result.len == arg->cap)
arg->result.data = krealloc(arg->result.data,
sizeof(dirent) * (arg->cap = arg->cap ? arg->cap*2 : 1));
arg->result.data[arg->result.len++] = (dirent) {
.name = str_clone(entn),
.size = fsize,
.is_dir = is_dir,
.children = 0,
};
return heritage == HER_SELF;
case HER_GRANDCHILD:
for (usize i = 0; i < arg->result.len; i++) {
dirent *d = &arg->result.data[i];
if (str_cmp(d->name, entn) == 0) {
d->size += fsize;
d->children++;
return false;
}
}
// orphan. this shouldn't happen
return false;
};
return false;
}
dir fs_readdir(str path)
{
fs_readdir_arg arg = {
.path = strip_trail(path),
.cap = 0,
.result = { 0, nil },
};
fs_walk(&fs_readdir_walker, &arg);
return arg.result;
}
|
