1 // SPDX-License-Identifier: GPL-2.0+ OR Apache-2.0
2 /*
3 * Created by Li Guifu <bluce.lee@aliyun.com>
4 */
5 #include <string.h>
6 #include <stdlib.h>
7 #include "erofs/err.h"
8 #include "erofs/list.h"
9 #include "erofs/print.h"
10 #include "erofs/exclude.h"
11 #include "erofs/internal.h"
12
13 #define EXCLUDE_RULE_EXACT_SIZE offsetof(struct erofs_exclude_rule, reg)
14 #define EXCLUDE_RULE_REGEX_SIZE sizeof(struct erofs_exclude_rule)
15
16 static LIST_HEAD(exclude_head);
17 static LIST_HEAD(regex_exclude_head);
18
dump_regerror(int errcode,const char * s,const regex_t * preg)19 static void dump_regerror(int errcode, const char *s, const regex_t *preg)
20 {
21 char str[512];
22
23 regerror(errcode, preg, str, sizeof(str));
24 erofs_err("invalid regex %s (%s)\n", s, str);
25 }
26
erofs_insert_exclude(const char * s,bool is_regex)27 static struct erofs_exclude_rule *erofs_insert_exclude(const char *s,
28 bool is_regex)
29 {
30 struct erofs_exclude_rule *r;
31 int ret;
32 struct list_head *h;
33
34 r = malloc(is_regex ? EXCLUDE_RULE_REGEX_SIZE :
35 EXCLUDE_RULE_EXACT_SIZE);
36 if (!r)
37 return ERR_PTR(-ENOMEM);
38
39 r->pattern = strdup(s);
40 if (!r->pattern) {
41 ret = -ENOMEM;
42 goto err_rule;
43 }
44
45 if (is_regex) {
46 ret = regcomp(&r->reg, s, REG_EXTENDED|REG_NOSUB);
47 if (ret) {
48 dump_regerror(ret, s, &r->reg);
49 goto err_rule;
50 }
51 h = ®ex_exclude_head;
52 } else {
53 h = &exclude_head;
54 }
55
56 list_add_tail(&r->list, h);
57 erofs_info("insert exclude %s: %s\n",
58 is_regex ? "regex" : "path", s);
59 return r;
60
61 err_rule:
62 if (r->pattern)
63 free(r->pattern);
64 free(r);
65 return ERR_PTR(ret);
66 }
67
erofs_cleanup_exclude_rules(void)68 void erofs_cleanup_exclude_rules(void)
69 {
70 struct erofs_exclude_rule *r, *n;
71 struct list_head *h;
72
73 h = &exclude_head;
74 list_for_each_entry_safe(r, n, h, list) {
75 list_del(&r->list);
76 free(r->pattern);
77 free(r);
78 }
79
80 h = ®ex_exclude_head;
81 list_for_each_entry_safe(r, n, h, list) {
82 list_del(&r->list);
83 free(r->pattern);
84 regfree(&r->reg);
85 free(r);
86 }
87 }
88
erofs_parse_exclude_path(const char * args,bool is_regex)89 int erofs_parse_exclude_path(const char *args, bool is_regex)
90 {
91 struct erofs_exclude_rule *r = erofs_insert_exclude(args, is_regex);
92
93 if (IS_ERR(r)) {
94 erofs_cleanup_exclude_rules();
95 return PTR_ERR(r);
96 }
97 return 0;
98 }
99
erofs_is_exclude_path(const char * dir,const char * name)100 struct erofs_exclude_rule *erofs_is_exclude_path(const char *dir,
101 const char *name)
102 {
103 char buf[PATH_MAX];
104 const char *s;
105 struct erofs_exclude_rule *r;
106
107 if (!dir) {
108 /* no prefix */
109 s = name;
110 } else {
111 sprintf(buf, "%s/%s", dir, name);
112 s = buf;
113 }
114
115 s = erofs_fspath(s);
116 list_for_each_entry(r, &exclude_head, list) {
117 if (!strcmp(r->pattern, s))
118 return r;
119 }
120
121 list_for_each_entry(r, ®ex_exclude_head, list) {
122 int ret = regexec(&r->reg, s, (size_t)0, NULL, 0);
123
124 if (!ret)
125 return r;
126 if (ret != REG_NOMATCH)
127 dump_regerror(ret, s, &r->reg);
128 }
129 return NULL;
130 }
131