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
173
174
175
176
|
/* Interface between GRUB's fs drivers and application code */
#include <console/console.h>
#include <fs/fs.h>
#include <string.h>
#include <stdlib.h>
int filepos;
int filemax;
fs_error_t errnum;
void (*disk_read_hook) (int, int, int);
void (*disk_read_func) (int, int, int);
char FSYS_BUF[FSYS_BUFLEN];
int fsmax;
struct fsys_entry {
char *name;
int (*mount_func) (void);
int (*read_func) (char *buf, int len);
int (*dir_func) (char *dirname);
void (*close_func) (void);
int (*embed_func) (int *start_sector, int needed_sectors);
};
struct fsys_entry fsys_table[] = {
# if CONFIG_FS_FAT == 1
{"fat", fat_mount, fat_read, fat_dir, 0, 0},
# endif
# if CONFIG_FS_EXT2 == 1
{"ext2fs", ext2fs_mount, ext2fs_read, ext2fs_dir, 0, 0},
# endif
# if CONFIG_FS_ISO9660 == 1
{"iso9660", iso9660_mount, iso9660_read, iso9660_dir, 0, 0},
# endif
};
/* NULLFS is used to read images from raw device */
static int nullfs_dir(char *name)
{
uint64_t dev_size;
if (name) {
printk_debug("can't have a named file\n");
return 0;
}
dev_size = (uint64_t) part_length << 9;
/* GRUB code doesn't like 2GB or bigger files */
if (dev_size > 0x7fffffff)
dev_size = 0x7fffffff;
filemax = dev_size;
return 1;
}
static int nullfs_read(char *buf, int len)
{
if (devread(filepos>>9, filepos&0x1ff, len, buf)) {
filepos += len;
return len;
} else
return 0;
}
static struct fsys_entry nullfs =
{"nullfs", 0, nullfs_read, nullfs_dir, 0, 0};
static struct fsys_entry *fsys;
int mount_fs(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(fsys_table); i++) {
if (fsys_table[i].mount_func()) {
fsys = &fsys_table[i];
printk_info("Mounted %s\n", fsys->name);
return 1;
}
}
fsys = 0;
printk_info("Unknown filesystem type\n");
return 0;
}
int file_open(const char *filename)
{
char *dev = 0;
const char *path;
int len;
int retval = 0;
int reopen;
path = strchr(filename, ':');
if (path) {
len = path - filename;
path++;
dev = malloc(len + 1);
memcpy(dev, filename, len);
dev[len] = '\0';
} else {
/* No colon is given. Is this device or filename? */
if (filename[0] == '/') {
/* Anything starts with '/' must be a filename */
dev = 0;
path = filename;
} else {
dev = strdup(filename);
path = 0;
}
}
if (dev && dev[0]) {
if (!devopen(dev, &reopen)) {
fsys = 0;
goto out;
}
if (!reopen)
fsys = 0;
}
if (path) {
if (!fsys || fsys==&nullfs) {
if (!mount_fs())
goto out;
}
using_devsize = 0;
if (!path[0]) {
printk_info("No filename is given\n");
goto out;
}
} else
fsys = &nullfs;
filepos = 0;
errnum = 0;
if (!fsys->dir_func((char *) path)) {
printk_info("File not found\n");
goto out;
}
retval = 1;
out:
if (dev)
free(dev);
return retval;
}
int file_read(void *buf, unsigned long len)
{
if (filepos < 0 || filepos > filemax)
filepos = filemax;
if (len < 0 || len > filemax-filepos)
len = filemax - filepos;
errnum = 0;
return fsys->read_func(buf, len);
}
int file_seek(unsigned long offset)
{
filepos = offset;
return filepos;
}
unsigned long file_pos(void)
{
return filepos;
}
unsigned long file_size(void)
{
return filemax;
}
void file_close(void)
{
}
|
