str_parms.c revision fe71a61e5b0cb666675900d206251a7c18ed944b 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "str_params"
18//#define LOG_NDEBUG 0
19
20#define _GNU_SOURCE 1
21#include <errno.h>
22#include <stdint.h>
23#include <stdio.h>
24#include <stdlib.h>
25#include <string.h>
26
27#include <cutils/hashmap.h>
28#include <cutils/log.h>
29#include <cutils/memory.h>
30
31#include <cutils/str_parms.h>
32
33struct str_parms {
34    Hashmap *map;
35};
36
37
38static bool str_eq(void *key_a, void *key_b)
39{
40    return !strcmp((const char *)key_a, (const char *)key_b);
41}
42
43/* use djb hash unless we find it inadequate */
44static int str_hash_fn(void *str)
45{
46    uint32_t hash = 5381;
47    char *p;
48
49    for (p = str; p && *p; p++)
50        hash = ((hash << 5) + hash) + *p;
51    return (int)hash;
52}
53
54struct str_parms *str_parms_create(void)
55{
56    struct str_parms *str_parms;
57
58    str_parms = calloc(1, sizeof(struct str_parms));
59    if (!str_parms)
60        return NULL;
61
62    str_parms->map = hashmapCreate(5, str_hash_fn, str_eq);
63    if (!str_parms->map)
64        goto err;
65
66    return str_parms;
67
68err:
69    free(str_parms);
70    return NULL;
71}
72
73static bool remove_pair(void *key, void *value, void *context)
74{
75    struct str_parms *str_parms = context;
76
77    hashmapRemove(str_parms->map, key);
78    free(key);
79    free(value);
80    return true;
81}
82
83void str_parms_destroy(struct str_parms *str_parms)
84{
85    hashmapForEach(str_parms->map, remove_pair, str_parms);
86    hashmapFree(str_parms->map);
87    free(str_parms);
88}
89
90struct str_parms *str_parms_create_str(const char *_string)
91{
92    struct str_parms *str_parms;
93    char *str;
94    char *kvpair;
95    char *tmpstr;
96    int items = 0;
97
98    str_parms = str_parms_create();
99    if (!str_parms)
100        goto err_create_str_parms;
101
102    str = strdup(_string);
103    if (!str)
104        goto err_strdup;
105
106    ALOGV("%s: source string == '%s'\n", __func__, _string);
107
108    kvpair = strtok_r(str, ";", &tmpstr);
109    while (kvpair && *kvpair) {
110        char *eq = strchr(kvpair, '='); /* would love strchrnul */
111        char *value;
112        char *key;
113        void *old_val;
114
115        if (eq == kvpair)
116            goto next_pair;
117
118        if (eq) {
119            key = strndup(kvpair, eq - kvpair);
120            if (*(++eq))
121                value = strdup(eq);
122            else
123                value = strdup("");
124        } else {
125            key = strdup(kvpair);
126            value = strdup("");
127        }
128
129        /* if we replaced a value, free it */
130        old_val = hashmapPut(str_parms->map, key, value);
131        if (old_val)
132            free(old_val);
133
134        items++;
135next_pair:
136        kvpair = strtok_r(NULL, ";", &tmpstr);
137    }
138
139    if (!items)
140        ALOGV("%s: no items found in string\n", __func__);
141
142    free(str);
143
144    return str_parms;
145
146err_strdup:
147    str_parms_destroy(str_parms);
148err_create_str_parms:
149    return NULL;
150}
151
152void str_parms_del(struct str_parms *str_parms, const char *key)
153{
154    hashmapRemove(str_parms->map, (void *)key);
155}
156
157int str_parms_add_str(struct str_parms *str_parms, const char *key,
158                      const char *value)
159{
160    void *old_val;
161    char *tmp;
162
163    tmp = strdup(value);
164    old_val = hashmapPut(str_parms->map, (void *)key, tmp);
165
166    if (old_val) {
167        free(old_val);
168    } else if (errno == ENOMEM) {
169        free(tmp);
170        return -ENOMEM;
171    }
172    return 0;
173}
174
175int str_parms_add_int(struct str_parms *str_parms, const char *key, int value)
176{
177    char val_str[12];
178    int ret;
179
180    ret = snprintf(val_str, sizeof(val_str), "%d", value);
181    if (ret < 0)
182        return -EINVAL;
183
184    ret = str_parms_add_str(str_parms, key, val_str);
185    return ret;
186}
187
188int str_parms_add_float(struct str_parms *str_parms, const char *key,
189                        float value)
190{
191    char val_str[23];
192    int ret;
193
194    ret = snprintf(val_str, sizeof(val_str), "%.10f", value);
195    if (ret < 0)
196        return -EINVAL;
197
198    ret = str_parms_add_str(str_parms, key, val_str);
199    return ret;
200}
201
202int str_parms_get_str(struct str_parms *str_parms, const char *key, char *val,
203                      int len)
204{
205    char *value;
206
207    value = hashmapGet(str_parms->map, (void *)key);
208    if (value)
209        return strlcpy(val, value, len);
210
211    return -ENOENT;
212}
213
214int str_parms_get_int(struct str_parms *str_parms, const char *key, int *val)
215{
216    char *value;
217    char *end;
218
219    value = hashmapGet(str_parms->map, (void *)key);
220    if (!value)
221        return -ENOENT;
222
223    *val = (int)strtol(value, &end, 0);
224    if (*value != '\0' && *end == '\0')
225        return 0;
226
227    return -EINVAL;
228}
229
230int str_parms_get_float(struct str_parms *str_parms, const char *key,
231                        float *val)
232{
233    float out;
234    char *value;
235    char *end;
236
237    value = hashmapGet(str_parms->map, (void *)key);
238    if (!value)
239        return -ENOENT;
240
241    out = strtof(value, &end);
242    if (*value != '\0' && *end == '\0')
243        return 0;
244
245    return -EINVAL;
246}
247
248static bool combine_strings(void *key, void *value, void *context)
249{
250    char **old_str = context;
251    char *new_str;
252    int ret;
253
254    ret = asprintf(&new_str, "%s%s%s=%s",
255                   *old_str ? *old_str : "",
256                   *old_str ? ";" : "",
257                   (char *)key,
258                   (char *)value);
259    if (*old_str)
260        free(*old_str);
261
262    if (ret >= 0) {
263        *old_str = new_str;
264        return true;
265    }
266
267    *old_str = NULL;
268    return false;
269}
270
271char *str_parms_to_str(struct str_parms *str_parms)
272{
273    char *str = NULL;
274
275    if (hashmapSize(str_parms->map) > 0)
276        hashmapForEach(str_parms->map, combine_strings, &str);
277    else
278        str = strdup("");
279    return str;
280}
281
282static bool dump_entry(void *key, void *value, void *context)
283{
284    ALOGI("key: '%s' value: '%s'\n", (char *)key, (char *)value);
285    return true;
286}
287
288void str_parms_dump(struct str_parms *str_parms)
289{
290    hashmapForEach(str_parms->map, dump_entry, str_parms);
291}
292
293#ifdef TEST_STR_PARMS
294static void test_str_parms_str(const char *str)
295{
296    struct str_parms *str_parms;
297    char *out_str;
298    int ret;
299
300    str_parms = str_parms_create_str(str);
301    str_parms_dump(str_parms);
302    out_str = str_parms_to_str(str_parms);
303    str_parms_destroy(str_parms);
304    ALOGI("%s: '%s' stringified is '%s'", __func__, str, out_str);
305    free(out_str);
306}
307
308int main(void)
309{
310    struct str_parms *str_parms;
311
312    test_str_parms_str("");
313    test_str_parms_str(";");
314    test_str_parms_str("=");
315    test_str_parms_str("=;");
316    test_str_parms_str("=bar");
317    test_str_parms_str("=bar;");
318    test_str_parms_str("foo=");
319    test_str_parms_str("foo=;");
320    test_str_parms_str("foo=bar");
321    test_str_parms_str("foo=bar;");
322    test_str_parms_str("foo=bar;baz");
323    test_str_parms_str("foo=bar;baz=");
324    test_str_parms_str("foo=bar;baz=bat");
325    test_str_parms_str("foo=bar;baz=bat;");
326
327    return 0;
328}
329#endif
330