1 /*
2 * This library is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU Lesser General Public
4 * License as published by the Free Software Foundation; either
5 * version 2 of the License, or (at your option) any later version.
6 *
7 * This library is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 * Lesser General Public License for more details.
11 *
12 * You should have received a copy of the GNU Lesser General Public
13 * License along with this library; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
15 *
16 * Support for the verb/device/modifier core logic and API,
17 * command line tool and file parser was kindly sponsored by
18 * Texas Instruments Inc.
19 * Support for multiple active modifiers and devices,
20 * transition sequences, multiple client access and user defined use
21 * cases was kindly sponsored by Wolfson Microelectronics PLC.
22 *
23 * Copyright (C) 2019 Red Hat Inc.
24 * Authors: Jaroslav Kysela <perex@perex.cz>
25 */
26
27 #include "ucm_local.h"
28 #include <ctype.h>
29 #include <regex.h>
30
get_string(snd_config_t * compound,const char * key,const char ** str)31 static int get_string(snd_config_t *compound, const char *key, const char **str)
32 {
33 snd_config_t *node;
34 int err;
35
36 err = snd_config_search(compound, key, &node);
37 if (err < 0)
38 return err;
39 return snd_config_get_string(node, str);
40 }
41
extract_substring(const char * data,regmatch_t * match)42 static char *extract_substring(const char *data, regmatch_t *match)
43 {
44 char *s;
45 size_t len;
46
47 len = match->rm_eo - match->rm_so;
48 s = malloc(len + 1);
49 if (s == NULL)
50 return NULL;
51 memcpy(s, data + match->rm_so, len);
52 s[len] = '\0';
53 return s;
54 }
55
set_variables(snd_use_case_mgr_t * uc_mgr,const char * data,unsigned int match_size,regmatch_t * match,const char * name)56 static int set_variables(snd_use_case_mgr_t *uc_mgr, const char *data,
57 unsigned int match_size, regmatch_t *match,
58 const char *name)
59 {
60 size_t name2_len = strlen(name) + 16;
61 char *name2 = alloca(name2_len);
62 char *s;
63 unsigned int i;
64 int err;
65
66 if (match[0].rm_so < 0 || match[0].rm_eo < 0)
67 return 0;
68 s = extract_substring(data, &match[0]);
69 if (s == NULL)
70 return -ENOMEM;
71 err = uc_mgr_set_variable(uc_mgr, name, s);
72 free(s);
73 if (err < 0)
74 return err;
75 for (i = 1; i < match_size; i++) {
76 if (match[0].rm_so < 0 || match[0].rm_eo < 0)
77 return 0;
78 s = extract_substring(data, &match[i]);
79 if (s == NULL)
80 return -ENOMEM;
81 snprintf(name2, name2_len, "%s%u", name, i);
82 err = uc_mgr_set_variable(uc_mgr, name2, s);
83 free(s);
84 if (err < 0)
85 return err;
86 }
87 return 0;
88 }
89
uc_mgr_define_regex(snd_use_case_mgr_t * uc_mgr,const char * name,snd_config_t * eval)90 int uc_mgr_define_regex(snd_use_case_mgr_t *uc_mgr, const char *name,
91 snd_config_t *eval)
92 {
93 const char *string, *regex_string, *flags_string;
94 char *s;
95 regex_t re;
96 int options = 0;
97 regmatch_t match[20];
98 int err;
99
100 if (uc_mgr->conf_format < 3) {
101 uc_error("define regex is supported in v3+ syntax");
102 return -EINVAL;
103 }
104
105 if (snd_config_get_type(eval) != SND_CONFIG_TYPE_COMPOUND) {
106 uc_error("compound type expected for DefineRegex");
107 return -EINVAL;
108 }
109
110 err = get_string(eval, "String", &string);
111 if (err < 0) {
112 uc_error("DefineRegex error (String)");
113 return -EINVAL;
114 }
115
116 err = get_string(eval, "Regex", ®ex_string);
117 if (err < 0) {
118 uc_error("DefineRegex error (Regex string)");
119 return -EINVAL;
120 }
121
122 err = get_string(eval, "Flags", &flags_string);
123 if (err == -ENOENT) {
124 options = REG_EXTENDED;
125 } else if (err < 0) {
126 uc_error("DefineRegex error (Flags string)");
127 return -EINVAL;
128 } else {
129 while (*flags_string) {
130 switch (tolower(*flags_string)) {
131 case 'e':
132 options |= REG_EXTENDED;
133 break;
134 case 'i':
135 options |= REG_ICASE;
136 break;
137 case 's':
138 options |= REG_NOSUB;
139 break;
140 case 'n':
141 options |= REG_NEWLINE;
142 break;
143 default:
144 uc_error("DefineRegex error (unknown flag '%c')", *flags_string);
145 return -EINVAL;
146 }
147 flags_string++;
148 }
149 }
150
151 err = uc_mgr_get_substituted_value(uc_mgr, &s, regex_string);
152 if (err < 0)
153 return err;
154 err = regcomp(&re, s, options);
155 free(s);
156 if (err) {
157 uc_error("Regex '%s' compilation failed (code %d)", err);
158 return -EINVAL;
159 }
160
161 err = uc_mgr_get_substituted_value(uc_mgr, &s, string);
162 if (err < 0) {
163 regfree(&re);
164 return err;
165 }
166 err = regexec(&re, s, ARRAY_SIZE(match), match, 0);
167 if (err < 0)
168 err = -errno;
169 else if (err == REG_NOMATCH)
170 err = 0;
171 else
172 err = set_variables(uc_mgr, s, ARRAY_SIZE(match), match, name);
173 free(s);
174 regfree(&re);
175 return err;
176 }
177