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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
* fstree.h
*
* Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
*/
#ifndef FSTREE_H
#define FSTREE_H
#include "config.h"
#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
#include "sqfs/predef.h"
#include "io/istream.h"
#include "compat.h"
#define FSTREE_MODE_HARD_LINK (0)
#define FSTREE_MODE_HARD_LINK_RESOLVED (1)
typedef struct fstree_defaults_t fstree_defaults_t;
typedef struct tree_node_t tree_node_t;
typedef struct file_info_t file_info_t;
typedef struct dir_info_t dir_info_t;
typedef struct fstree_t fstree_t;
#define container_of(ptr, type, member) \
((type *)((char *)ptr - offsetof(type, member)))
/* Additional meta data stored in a tree_node_t for regular files. */
struct file_info_t {
/* Linked list pointer for files in fstree_t */
file_info_t *next;
/* Path to the input file. */
char *input_file;
sqfs_inode_generic_t *inode;
/* used by sort file processing */
sqfs_s64 priority;
int flags;
bool already_matched;
};
/* Additional meta data stored in a tree_node_t for directories */
struct dir_info_t {
/* Linked list head for children in the directory */
tree_node_t *children;
/* Set to true for implicitly generated directories. */
bool created_implicitly;
};
/* A node in a file system tree */
struct tree_node_t {
/* Parent directory children linked list pointer. */
tree_node_t *next;
/* Root node has this set to NULL. */
tree_node_t *parent;
/* For the root node, this points to an empty string. */
char *name;
sqfs_u32 xattr_idx;
sqfs_u32 uid;
sqfs_u32 gid;
sqfs_u32 inode_num;
sqfs_u32 mod_time;
sqfs_u32 link_count;
sqfs_u16 mode;
/* SquashFS inode refernce number. 32 bit offset of the meta data
block start (relative to inode table start), shifted left by 16
and ored with a 13 bit offset into the uncompressed meta data block.
Generated on the fly when writing inodes. */
sqfs_u64 inode_ref;
/* Type specific data. "target" pointer is into payload area below. */
union {
dir_info_t dir;
file_info_t file;
char *target;
sqfs_u64 devno;
tree_node_t *target_node;
} data;
sqfs_u8 payload[];
};
/* Default settings for new nodes */
struct fstree_defaults_t {
sqfs_u32 uid;
sqfs_u32 gid;
sqfs_u32 mtime;
sqfs_u16 mode;
};
/* Encapsulates a file system tree */
struct fstree_t {
fstree_defaults_t defaults;
size_t unique_inode_count;
/* flat array of all nodes that have an inode number */
tree_node_t **inodes;
tree_node_t *root;
/* linear linked list of all regular files */
file_info_t *files;
};
/*
Initializing means copying over the default values and creating a root node.
On error, an error message is written to stderr.
Returns 0 on success.
*/
int fstree_init(fstree_t *fs, const fstree_defaults_t *defaults);
void fstree_cleanup(fstree_t *fs);
/*
Create a tree node from a struct stat, node name and extra data.
For symlinks, the extra part is interpreted as target. For regular files, it
is interpreted as input path (can be NULL). The name doesn't have to be null
terminated, a length has to be specified.
This function does not print anything to stderr, instead it sets an
appropriate errno value.
The resulting node can be freed with a single free() call.
*/
tree_node_t *fstree_mknode(tree_node_t *parent, const char *name,
size_t name_len, const char *extra,
const struct stat *sb);
/*
Add a node to an fstree at a specific path.
If some components of the path don't exist, they are created as directories
with default permissions, like mkdir -p would, and marked as implcitily
created. A subsequent call that tries to create an existing tree node will
fail, except if the target is an implicitly created directory node and the
call tries to create it as a directory (this will simply overwrite the
permissions and ownership). The implicitly created flag is then cleared.
Subsequent attempts to create an existing directory again will then also
fail.
This function does not print anything to stderr, instead it sets an
appropriate errno value. Internally it uses fstree_mknode to create the node.
*/
tree_node_t *fstree_add_generic(fstree_t *fs, const char *path,
const struct stat *sb, const char *extra);
/*
This function performs all the necessary post processing steps on the file
system tree, i.e. recursively sorting all directory entries by name,
allocating inode numbers, resolving hard links and stringing all files nodes
together into a linked list.
The total inode count is stored in unique_inode_count. The head of the file
list is pointed to by fs->files.
The "inodes" array is allocated and each node that has an inode number is
mapped into the array at index inode_num - 1.
Returns 0 on success, prints to stderr on failure.
*/
int fstree_post_process(fstree_t *fs);
/*
Generate a string holding the full path of a node. Returned
string must be freed.
Returns NULL on failure and sets errno.
*/
char *fstree_get_path(tree_node_t *node);
/*
Resolve a path to a tree node. Returns NULL on failure and sets errno.
If "create_implicitly" is set to true, the function acts essentially like
mkdir_p if part of the path doesn't exist yet.
If "stop_at_parent" is true, the function stops at the last component and
returns the parent or would-be-parent of the last path component, but doesn't
check if the last path component exists or not.
*/
tree_node_t *fstree_get_node_by_path(fstree_t *fs, tree_node_t *root,
const char *path, bool create_implicitly,
bool stop_at_parent);
/*
Add a hard link node. Returns NULL on failure and sets errno.
*/
tree_node_t *fstree_add_hard_link(fstree_t *fs, const char *path,
const char *target);
/*
Try to resolve all hard links in the tree.
Returns 0 on success. On failure, errno is set.
*/
int fstree_resolve_hard_links(fstree_t *fs);
void fstree_insert_sorted(tree_node_t *root, tree_node_t *n);
#endif /* FSTREE_H */
|
