1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * erofs-utils/lib/exclude.c
4 *
5 * Created by Li Guifu <bluce.lee@aliyun.com>
6 */
7 #include <string.h>
8 #include <stdlib.h>
9 #include "erofs/err.h"
10 #include "erofs/list.h"
11 #include "erofs/print.h"
12 #include "erofs/exclude.h"
13
14 #define EXCLUDE_RULE_EXACT_SIZE offsetof(struct erofs_exclude_rule, reg)
15 #define EXCLUDE_RULE_REGEX_SIZE sizeof(struct erofs_exclude_rule)
16
17 static LIST_HEAD(exclude_head);
18 static LIST_HEAD(regex_exclude_head);
19
dump_regerror(int errcode,const char * s,const regex_t * preg)20 static void dump_regerror(int errcode, const char *s, const regex_t *preg)
21 {
22 char str[512];
23
24 regerror(errcode, preg, str, sizeof(str));
25 erofs_err("invalid regex %s (%s)\n", s, str);
26 }
27
erofs_insert_exclude(const char * s,bool is_regex)28 static struct erofs_exclude_rule *erofs_insert_exclude(const char *s,
29 bool is_regex)
30 {
31 struct erofs_exclude_rule *r;
32 int ret;
33 struct list_head *h;
34
35 r = malloc(is_regex ? EXCLUDE_RULE_REGEX_SIZE :
36 EXCLUDE_RULE_EXACT_SIZE);
37 if (!r)
38 return ERR_PTR(-ENOMEM);
39
40 r->pattern = strdup(s);
41 if (!r->pattern) {
42 ret = -ENOMEM;
43 goto err_rule;
44 }
45
46 if (is_regex) {
47 ret = regcomp(&r->reg, s, REG_EXTENDED|REG_NOSUB);
48 if (ret) {
49 dump_regerror(ret, s, &r->reg);
50 goto err_rule;
51 }
52 h = ®ex_exclude_head;
53 } else {
54 h = &exclude_head;
55 }
56
57 list_add_tail(&r->list, h);
58 erofs_info("insert exclude %s: %s\n",
59 is_regex ? "regex" : "path", s);
60 return r;
61
62 err_rule:
63 if (r->pattern)
64 free(r->pattern);
65 free(r);
66 return ERR_PTR(ret);
67 }
68
erofs_cleanup_exclude_rules(void)69 void erofs_cleanup_exclude_rules(void)
70 {
71 struct erofs_exclude_rule *r, *n;
72 struct list_head *h;
73
74 h = &exclude_head;
75 list_for_each_entry_safe(r, n, h, list) {
76 list_del(&r->list);
77 free(r->pattern);
78 free(r);
79 }
80
81 h = ®ex_exclude_head;
82 list_for_each_entry_safe(r, n, h, list) {
83 list_del(&r->list);
84 free(r->pattern);
85 regfree(&r->reg);
86 free(r);
87 }
88 }
89
erofs_parse_exclude_path(const char * args,bool is_regex)90 int erofs_parse_exclude_path(const char *args, bool is_regex)
91 {
92 struct erofs_exclude_rule *r = erofs_insert_exclude(args, is_regex);
93
94 if (IS_ERR(r)) {
95 erofs_cleanup_exclude_rules();
96 return PTR_ERR(r);
97 }
98 return 0;
99 }
100
erofs_is_exclude_path(const char * dir,const char * name)101 struct erofs_exclude_rule *erofs_is_exclude_path(const char *dir,
102 const char *name)
103 {
104 char buf[PATH_MAX];
105 const char *s;
106 struct erofs_exclude_rule *r;
107
108 if (!dir) {
109 /* no prefix */
110 s = name;
111 } else {
112 sprintf(buf, "%s/%s", dir, name);
113 s = buf;
114 }
115
116 s = erofs_fspath(s);
117 list_for_each_entry(r, &exclude_head, list) {
118 if (!strcmp(r->pattern, s))
119 return r;
120 }
121
122 list_for_each_entry(r, ®ex_exclude_head, list) {
123 int ret = regexec(&r->reg, s, (size_t)0, NULL, 0);
124
125 if (!ret)
126 return r;
127 if (ret != REG_NOMATCH)
128 dump_regerror(ret, s, &r->reg);
129 }
130 return NULL;
131 }
132
133