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a6826fbc WD |
1 | /* |
2 | * This implementation is based on code from uClibc-0.9.30.3 but was | |
3 | * modified and extended for use within U-Boot. | |
4 | * | |
5 | * Copyright (C) 2010 Wolfgang Denk <wd@denx.de> | |
6 | * | |
7 | * Original license header: | |
8 | * | |
9 | * Copyright (C) 1993, 1995, 1996, 1997, 2002 Free Software Foundation, Inc. | |
10 | * This file is part of the GNU C Library. | |
11 | * Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1993. | |
12 | * | |
13 | * The GNU C Library is free software; you can redistribute it and/or | |
14 | * modify it under the terms of the GNU Lesser General Public | |
15 | * License as published by the Free Software Foundation; either | |
16 | * version 2.1 of the License, or (at your option) any later version. | |
17 | * | |
18 | * The GNU C Library is distributed in the hope that it will be useful, | |
19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
21 | * Lesser General Public License for more details. | |
22 | * | |
23 | * You should have received a copy of the GNU Lesser General Public | |
24 | * License along with the GNU C Library; if not, write to the Free | |
25 | * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |
26 | * 02111-1307 USA. | |
27 | */ | |
28 | ||
29 | #include <errno.h> | |
30 | #include <malloc.h> | |
31 | ||
32 | #ifdef USE_HOSTCC /* HOST build */ | |
33 | # include <string.h> | |
34 | # include <assert.h> | |
4d91a6ec | 35 | # include <ctype.h> |
a6826fbc WD |
36 | |
37 | # ifndef debug | |
38 | # ifdef DEBUG | |
39 | # define debug(fmt,args...) printf(fmt ,##args) | |
40 | # else | |
41 | # define debug(fmt,args...) | |
42 | # endif | |
43 | # endif | |
44 | #else /* U-Boot build */ | |
45 | # include <common.h> | |
46 | # include <linux/string.h> | |
4d91a6ec | 47 | # include <linux/ctype.h> |
a6826fbc WD |
48 | #endif |
49 | ||
fc5fc76b AB |
50 | #ifndef CONFIG_ENV_MIN_ENTRIES /* minimum number of entries */ |
51 | #define CONFIG_ENV_MIN_ENTRIES 64 | |
52 | #endif | |
ea882baf WD |
53 | #ifndef CONFIG_ENV_MAX_ENTRIES /* maximum number of entries */ |
54 | #define CONFIG_ENV_MAX_ENTRIES 512 | |
55 | #endif | |
56 | ||
a6826fbc WD |
57 | #include "search.h" |
58 | ||
59 | /* | |
60 | * [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986 | |
071bc923 | 61 | * [Knuth] The Art of Computer Programming, part 3 (6.4) |
a6826fbc WD |
62 | */ |
63 | ||
a6826fbc WD |
64 | /* |
65 | * The reentrant version has no static variables to maintain the state. | |
66 | * Instead the interface of all functions is extended to take an argument | |
67 | * which describes the current status. | |
68 | */ | |
69 | typedef struct _ENTRY { | |
c81c1222 | 70 | int used; |
a6826fbc WD |
71 | ENTRY entry; |
72 | } _ENTRY; | |
73 | ||
74 | ||
75 | /* | |
76 | * hcreate() | |
77 | */ | |
78 | ||
79 | /* | |
80 | * For the used double hash method the table size has to be a prime. To | |
81 | * correct the user given table size we need a prime test. This trivial | |
82 | * algorithm is adequate because | |
83 | * a) the code is (most probably) called a few times per program run and | |
84 | * b) the number is small because the table must fit in the core | |
85 | * */ | |
86 | static int isprime(unsigned int number) | |
87 | { | |
88 | /* no even number will be passed */ | |
89 | unsigned int div = 3; | |
90 | ||
91 | while (div * div < number && number % div != 0) | |
92 | div += 2; | |
93 | ||
94 | return number % div != 0; | |
95 | } | |
96 | ||
a6826fbc WD |
97 | /* |
98 | * Before using the hash table we must allocate memory for it. | |
99 | * Test for an existing table are done. We allocate one element | |
100 | * more as the found prime number says. This is done for more effective | |
101 | * indexing as explained in the comment for the hsearch function. | |
102 | * The contents of the table is zeroed, especially the field used | |
103 | * becomes zero. | |
104 | */ | |
2eb1573f | 105 | |
a6826fbc WD |
106 | int hcreate_r(size_t nel, struct hsearch_data *htab) |
107 | { | |
108 | /* Test for correct arguments. */ | |
109 | if (htab == NULL) { | |
110 | __set_errno(EINVAL); | |
111 | return 0; | |
112 | } | |
113 | ||
114 | /* There is still another table active. Return with error. */ | |
115 | if (htab->table != NULL) | |
116 | return 0; | |
117 | ||
118 | /* Change nel to the first prime number not smaller as nel. */ | |
119 | nel |= 1; /* make odd */ | |
120 | while (!isprime(nel)) | |
121 | nel += 2; | |
122 | ||
123 | htab->size = nel; | |
124 | htab->filled = 0; | |
125 | ||
126 | /* allocate memory and zero out */ | |
127 | htab->table = (_ENTRY *) calloc(htab->size + 1, sizeof(_ENTRY)); | |
128 | if (htab->table == NULL) | |
129 | return 0; | |
130 | ||
131 | /* everything went alright */ | |
132 | return 1; | |
133 | } | |
134 | ||
135 | ||
136 | /* | |
137 | * hdestroy() | |
138 | */ | |
a6826fbc WD |
139 | |
140 | /* | |
141 | * After using the hash table it has to be destroyed. The used memory can | |
142 | * be freed and the local static variable can be marked as not used. | |
143 | */ | |
2eb1573f | 144 | |
152874b6 | 145 | void hdestroy_r(struct hsearch_data *htab, int do_apply) |
a6826fbc WD |
146 | { |
147 | int i; | |
148 | ||
149 | /* Test for correct arguments. */ | |
150 | if (htab == NULL) { | |
151 | __set_errno(EINVAL); | |
152 | return; | |
153 | } | |
154 | ||
155 | /* free used memory */ | |
156 | for (i = 1; i <= htab->size; ++i) { | |
c81c1222 | 157 | if (htab->table[i].used > 0) { |
a6826fbc | 158 | ENTRY *ep = &htab->table[i].entry; |
152874b6 GF |
159 | if (do_apply && htab->apply != NULL) { |
160 | /* deletion is always forced */ | |
161 | htab->apply(ep->key, ep->data, NULL, H_FORCE); | |
162 | } | |
84b5e802 | 163 | free((void *)ep->key); |
a6826fbc WD |
164 | free(ep->data); |
165 | } | |
166 | } | |
167 | free(htab->table); | |
168 | ||
169 | /* the sign for an existing table is an value != NULL in htable */ | |
170 | htab->table = NULL; | |
171 | } | |
172 | ||
173 | /* | |
174 | * hsearch() | |
175 | */ | |
176 | ||
177 | /* | |
178 | * This is the search function. It uses double hashing with open addressing. | |
179 | * The argument item.key has to be a pointer to an zero terminated, most | |
180 | * probably strings of chars. The function for generating a number of the | |
181 | * strings is simple but fast. It can be replaced by a more complex function | |
182 | * like ajw (see [Aho,Sethi,Ullman]) if the needs are shown. | |
183 | * | |
184 | * We use an trick to speed up the lookup. The table is created by hcreate | |
185 | * with one more element available. This enables us to use the index zero | |
186 | * special. This index will never be used because we store the first hash | |
187 | * index in the field used where zero means not used. Every other value | |
188 | * means used. The used field can be used as a first fast comparison for | |
189 | * equality of the stored and the parameter value. This helps to prevent | |
190 | * unnecessary expensive calls of strcmp. | |
191 | * | |
192 | * This implementation differs from the standard library version of | |
193 | * this function in a number of ways: | |
194 | * | |
195 | * - While the standard version does not make any assumptions about | |
196 | * the type of the stored data objects at all, this implementation | |
197 | * works with NUL terminated strings only. | |
198 | * - Instead of storing just pointers to the original objects, we | |
199 | * create local copies so the caller does not need to care about the | |
200 | * data any more. | |
201 | * - The standard implementation does not provide a way to update an | |
202 | * existing entry. This version will create a new entry or update an | |
203 | * existing one when both "action == ENTER" and "item.data != NULL". | |
204 | * - Instead of returning 1 on success, we return the index into the | |
205 | * internal hash table, which is also guaranteed to be positive. | |
206 | * This allows us direct access to the found hash table slot for | |
207 | * example for functions like hdelete(). | |
208 | */ | |
209 | ||
a000b795 KP |
210 | /* |
211 | * hstrstr_r - return index to entry whose key and/or data contains match | |
212 | */ | |
213 | int hstrstr_r(const char *match, int last_idx, ENTRY ** retval, | |
214 | struct hsearch_data *htab) | |
215 | { | |
216 | unsigned int idx; | |
217 | ||
218 | for (idx = last_idx + 1; idx < htab->size; ++idx) { | |
219 | if (htab->table[idx].used <= 0) | |
220 | continue; | |
221 | if (strstr(htab->table[idx].entry.key, match) || | |
222 | strstr(htab->table[idx].entry.data, match)) { | |
223 | *retval = &htab->table[idx].entry; | |
224 | return idx; | |
225 | } | |
226 | } | |
227 | ||
228 | __set_errno(ESRCH); | |
229 | *retval = NULL; | |
230 | return 0; | |
231 | } | |
232 | ||
560d424b MF |
233 | int hmatch_r(const char *match, int last_idx, ENTRY ** retval, |
234 | struct hsearch_data *htab) | |
235 | { | |
236 | unsigned int idx; | |
237 | size_t key_len = strlen(match); | |
238 | ||
239 | for (idx = last_idx + 1; idx < htab->size; ++idx) { | |
af4d9074 | 240 | if (htab->table[idx].used <= 0) |
560d424b MF |
241 | continue; |
242 | if (!strncmp(match, htab->table[idx].entry.key, key_len)) { | |
243 | *retval = &htab->table[idx].entry; | |
244 | return idx; | |
245 | } | |
246 | } | |
247 | ||
248 | __set_errno(ESRCH); | |
249 | *retval = NULL; | |
250 | return 0; | |
251 | } | |
252 | ||
a6826fbc WD |
253 | int hsearch_r(ENTRY item, ACTION action, ENTRY ** retval, |
254 | struct hsearch_data *htab) | |
255 | { | |
256 | unsigned int hval; | |
257 | unsigned int count; | |
258 | unsigned int len = strlen(item.key); | |
259 | unsigned int idx; | |
c81c1222 | 260 | unsigned int first_deleted = 0; |
a6826fbc WD |
261 | |
262 | /* Compute an value for the given string. Perhaps use a better method. */ | |
263 | hval = len; | |
264 | count = len; | |
265 | while (count-- > 0) { | |
266 | hval <<= 4; | |
267 | hval += item.key[count]; | |
268 | } | |
269 | ||
270 | /* | |
271 | * First hash function: | |
272 | * simply take the modul but prevent zero. | |
273 | */ | |
274 | hval %= htab->size; | |
275 | if (hval == 0) | |
276 | ++hval; | |
277 | ||
278 | /* The first index tried. */ | |
279 | idx = hval; | |
280 | ||
281 | if (htab->table[idx].used) { | |
282 | /* | |
071bc923 | 283 | * Further action might be required according to the |
a6826fbc WD |
284 | * action value. |
285 | */ | |
286 | unsigned hval2; | |
287 | ||
c81c1222 PB |
288 | if (htab->table[idx].used == -1 |
289 | && !first_deleted) | |
290 | first_deleted = idx; | |
291 | ||
a6826fbc WD |
292 | if (htab->table[idx].used == hval |
293 | && strcmp(item.key, htab->table[idx].entry.key) == 0) { | |
294 | /* Overwrite existing value? */ | |
295 | if ((action == ENTER) && (item.data != NULL)) { | |
296 | free(htab->table[idx].entry.data); | |
297 | htab->table[idx].entry.data = | |
298 | strdup(item.data); | |
299 | if (!htab->table[idx].entry.data) { | |
300 | __set_errno(ENOMEM); | |
301 | *retval = NULL; | |
302 | return 0; | |
303 | } | |
304 | } | |
305 | /* return found entry */ | |
306 | *retval = &htab->table[idx].entry; | |
307 | return idx; | |
308 | } | |
309 | ||
310 | /* | |
311 | * Second hash function: | |
312 | * as suggested in [Knuth] | |
313 | */ | |
314 | hval2 = 1 + hval % (htab->size - 2); | |
315 | ||
316 | do { | |
317 | /* | |
071bc923 WD |
318 | * Because SIZE is prime this guarantees to |
319 | * step through all available indices. | |
a6826fbc WD |
320 | */ |
321 | if (idx <= hval2) | |
322 | idx = htab->size + idx - hval2; | |
323 | else | |
324 | idx -= hval2; | |
325 | ||
326 | /* | |
327 | * If we visited all entries leave the loop | |
328 | * unsuccessfully. | |
329 | */ | |
330 | if (idx == hval) | |
331 | break; | |
332 | ||
333 | /* If entry is found use it. */ | |
334 | if ((htab->table[idx].used == hval) | |
335 | && strcmp(item.key, htab->table[idx].entry.key) == 0) { | |
336 | /* Overwrite existing value? */ | |
337 | if ((action == ENTER) && (item.data != NULL)) { | |
338 | free(htab->table[idx].entry.data); | |
339 | htab->table[idx].entry.data = | |
340 | strdup(item.data); | |
341 | if (!htab->table[idx].entry.data) { | |
342 | __set_errno(ENOMEM); | |
343 | *retval = NULL; | |
344 | return 0; | |
345 | } | |
346 | } | |
347 | /* return found entry */ | |
348 | *retval = &htab->table[idx].entry; | |
349 | return idx; | |
350 | } | |
351 | } | |
352 | while (htab->table[idx].used); | |
353 | } | |
354 | ||
355 | /* An empty bucket has been found. */ | |
356 | if (action == ENTER) { | |
357 | /* | |
071bc923 WD |
358 | * If table is full and another entry should be |
359 | * entered return with error. | |
a6826fbc WD |
360 | */ |
361 | if (htab->filled == htab->size) { | |
362 | __set_errno(ENOMEM); | |
363 | *retval = NULL; | |
364 | return 0; | |
365 | } | |
366 | ||
367 | /* | |
368 | * Create new entry; | |
369 | * create copies of item.key and item.data | |
370 | */ | |
c81c1222 PB |
371 | if (first_deleted) |
372 | idx = first_deleted; | |
373 | ||
a6826fbc WD |
374 | htab->table[idx].used = hval; |
375 | htab->table[idx].entry.key = strdup(item.key); | |
376 | htab->table[idx].entry.data = strdup(item.data); | |
377 | if (!htab->table[idx].entry.key || | |
378 | !htab->table[idx].entry.data) { | |
379 | __set_errno(ENOMEM); | |
380 | *retval = NULL; | |
381 | return 0; | |
382 | } | |
383 | ||
384 | ++htab->filled; | |
385 | ||
386 | /* return new entry */ | |
387 | *retval = &htab->table[idx].entry; | |
388 | return 1; | |
389 | } | |
390 | ||
391 | __set_errno(ESRCH); | |
392 | *retval = NULL; | |
393 | return 0; | |
394 | } | |
395 | ||
396 | ||
397 | /* | |
398 | * hdelete() | |
399 | */ | |
400 | ||
401 | /* | |
402 | * The standard implementation of hsearch(3) does not provide any way | |
403 | * to delete any entries from the hash table. We extend the code to | |
404 | * do that. | |
405 | */ | |
406 | ||
152874b6 | 407 | int hdelete_r(const char *key, struct hsearch_data *htab, int do_apply) |
a6826fbc WD |
408 | { |
409 | ENTRY e, *ep; | |
410 | int idx; | |
411 | ||
412 | debug("hdelete: DELETE key \"%s\"\n", key); | |
413 | ||
414 | e.key = (char *)key; | |
415 | ||
416 | if ((idx = hsearch_r(e, FIND, &ep, htab)) == 0) { | |
417 | __set_errno(ESRCH); | |
418 | return 0; /* not found */ | |
419 | } | |
420 | ||
421 | /* free used ENTRY */ | |
422 | debug("hdelete: DELETING key \"%s\"\n", key); | |
152874b6 GF |
423 | if (do_apply && htab->apply != NULL) |
424 | htab->apply(ep->key, ep->data, NULL, H_FORCE); | |
84b5e802 | 425 | free((void *)ep->key); |
a6826fbc | 426 | free(ep->data); |
c81c1222 | 427 | htab->table[idx].used = -1; |
a6826fbc WD |
428 | |
429 | --htab->filled; | |
430 | ||
431 | return 1; | |
432 | } | |
433 | ||
434 | /* | |
435 | * hexport() | |
436 | */ | |
437 | ||
438 | /* | |
439 | * Export the data stored in the hash table in linearized form. | |
440 | * | |
441 | * Entries are exported as "name=value" strings, separated by an | |
442 | * arbitrary (non-NUL, of course) separator character. This allows to | |
443 | * use this function both when formatting the U-Boot environment for | |
444 | * external storage (using '\0' as separator), but also when using it | |
445 | * for the "printenv" command to print all variables, simply by using | |
446 | * as '\n" as separator. This can also be used for new features like | |
447 | * exporting the environment data as text file, including the option | |
448 | * for later re-import. | |
449 | * | |
450 | * The entries in the result list will be sorted by ascending key | |
451 | * values. | |
452 | * | |
453 | * If the separator character is different from NUL, then any | |
454 | * separator characters and backslash characters in the values will | |
455 | * be escaped by a preceeding backslash in output. This is needed for | |
456 | * example to enable multi-line values, especially when the output | |
457 | * shall later be parsed (for example, for re-import). | |
458 | * | |
459 | * There are several options how the result buffer is handled: | |
460 | * | |
461 | * *resp size | |
462 | * ----------- | |
463 | * NULL 0 A string of sufficient length will be allocated. | |
464 | * NULL >0 A string of the size given will be | |
465 | * allocated. An error will be returned if the size is | |
466 | * not sufficient. Any unused bytes in the string will | |
467 | * be '\0'-padded. | |
468 | * !NULL 0 The user-supplied buffer will be used. No length | |
469 | * checking will be performed, i. e. it is assumed that | |
470 | * the buffer size will always be big enough. DANGEROUS. | |
471 | * !NULL >0 The user-supplied buffer will be used. An error will | |
472 | * be returned if the size is not sufficient. Any unused | |
473 | * bytes in the string will be '\0'-padded. | |
474 | */ | |
475 | ||
a6826fbc WD |
476 | static int cmpkey(const void *p1, const void *p2) |
477 | { | |
478 | ENTRY *e1 = *(ENTRY **) p1; | |
479 | ENTRY *e2 = *(ENTRY **) p2; | |
480 | ||
481 | return (strcmp(e1->key, e2->key)); | |
482 | } | |
483 | ||
484 | ssize_t hexport_r(struct hsearch_data *htab, const char sep, | |
37f2fe74 WD |
485 | char **resp, size_t size, |
486 | int argc, char * const argv[]) | |
a6826fbc WD |
487 | { |
488 | ENTRY *list[htab->size]; | |
489 | char *res, *p; | |
490 | size_t totlen; | |
491 | int i, n; | |
492 | ||
493 | /* Test for correct arguments. */ | |
494 | if ((resp == NULL) || (htab == NULL)) { | |
495 | __set_errno(EINVAL); | |
496 | return (-1); | |
497 | } | |
498 | ||
ff856286 SG |
499 | debug("EXPORT table = %p, htab.size = %d, htab.filled = %d, " |
500 | "size = %zu\n", htab, htab->size, htab->filled, size); | |
a6826fbc WD |
501 | /* |
502 | * Pass 1: | |
503 | * search used entries, | |
504 | * save addresses and compute total length | |
505 | */ | |
506 | for (i = 1, n = 0, totlen = 0; i <= htab->size; ++i) { | |
507 | ||
c81c1222 | 508 | if (htab->table[i].used > 0) { |
a6826fbc | 509 | ENTRY *ep = &htab->table[i].entry; |
37f2fe74 WD |
510 | int arg, found = 0; |
511 | ||
512 | for (arg = 0; arg < argc; ++arg) { | |
513 | if (strcmp(argv[arg], ep->key) == 0) { | |
514 | found = 1; | |
515 | break; | |
516 | } | |
517 | } | |
518 | if ((argc > 0) && (found == 0)) | |
519 | continue; | |
a6826fbc WD |
520 | |
521 | list[n++] = ep; | |
522 | ||
523 | totlen += strlen(ep->key) + 2; | |
524 | ||
525 | if (sep == '\0') { | |
526 | totlen += strlen(ep->data); | |
527 | } else { /* check if escapes are needed */ | |
528 | char *s = ep->data; | |
529 | ||
530 | while (*s) { | |
531 | ++totlen; | |
532 | /* add room for needed escape chars */ | |
533 | if ((*s == sep) || (*s == '\\')) | |
534 | ++totlen; | |
535 | ++s; | |
536 | } | |
537 | } | |
538 | totlen += 2; /* for '=' and 'sep' char */ | |
539 | } | |
540 | } | |
541 | ||
542 | #ifdef DEBUG | |
543 | /* Pass 1a: print unsorted list */ | |
544 | printf("Unsorted: n=%d\n", n); | |
545 | for (i = 0; i < n; ++i) { | |
546 | printf("\t%3d: %p ==> %-10s => %s\n", | |
547 | i, list[i], list[i]->key, list[i]->data); | |
548 | } | |
549 | #endif | |
550 | ||
551 | /* Sort list by keys */ | |
552 | qsort(list, n, sizeof(ENTRY *), cmpkey); | |
553 | ||
554 | /* Check if the user supplied buffer size is sufficient */ | |
555 | if (size) { | |
556 | if (size < totlen + 1) { /* provided buffer too small */ | |
ff856286 SG |
557 | printf("Env export buffer too small: %zu, " |
558 | "but need %zu\n", size, totlen + 1); | |
a6826fbc WD |
559 | __set_errno(ENOMEM); |
560 | return (-1); | |
561 | } | |
562 | } else { | |
563 | size = totlen + 1; | |
564 | } | |
565 | ||
566 | /* Check if the user provided a buffer */ | |
567 | if (*resp) { | |
568 | /* yes; clear it */ | |
569 | res = *resp; | |
570 | memset(res, '\0', size); | |
571 | } else { | |
572 | /* no, allocate and clear one */ | |
573 | *resp = res = calloc(1, size); | |
574 | if (res == NULL) { | |
575 | __set_errno(ENOMEM); | |
576 | return (-1); | |
577 | } | |
578 | } | |
579 | /* | |
580 | * Pass 2: | |
581 | * export sorted list of result data | |
582 | */ | |
583 | for (i = 0, p = res; i < n; ++i) { | |
84b5e802 | 584 | const char *s; |
a6826fbc WD |
585 | |
586 | s = list[i]->key; | |
587 | while (*s) | |
588 | *p++ = *s++; | |
589 | *p++ = '='; | |
590 | ||
591 | s = list[i]->data; | |
592 | ||
593 | while (*s) { | |
594 | if ((*s == sep) || (*s == '\\')) | |
595 | *p++ = '\\'; /* escape */ | |
596 | *p++ = *s++; | |
597 | } | |
598 | *p++ = sep; | |
599 | } | |
600 | *p = '\0'; /* terminate result */ | |
601 | ||
602 | return size; | |
603 | } | |
604 | ||
605 | ||
606 | /* | |
607 | * himport() | |
608 | */ | |
609 | ||
d5370feb GF |
610 | /* |
611 | * Check whether variable 'name' is amongst vars[], | |
612 | * and remove all instances by setting the pointer to NULL | |
613 | */ | |
614 | static int drop_var_from_set(const char *name, int nvars, char * vars[]) | |
348b1f1c GF |
615 | { |
616 | int i = 0; | |
d5370feb | 617 | int res = 0; |
348b1f1c GF |
618 | |
619 | /* No variables specified means process all of them */ | |
620 | if (nvars == 0) | |
621 | return 1; | |
622 | ||
623 | for (i = 0; i < nvars; i++) { | |
d5370feb GF |
624 | if (vars[i] == NULL) |
625 | continue; | |
626 | /* If we found it, delete all of them */ | |
627 | if (!strcmp(name, vars[i])) { | |
628 | vars[i] = NULL; | |
629 | res = 1; | |
630 | } | |
348b1f1c | 631 | } |
d5370feb GF |
632 | if (!res) |
633 | debug("Skipping non-listed variable %s\n", name); | |
348b1f1c | 634 | |
d5370feb | 635 | return res; |
348b1f1c GF |
636 | } |
637 | ||
a6826fbc WD |
638 | /* |
639 | * Import linearized data into hash table. | |
640 | * | |
641 | * This is the inverse function to hexport(): it takes a linear list | |
642 | * of "name=value" pairs and creates hash table entries from it. | |
643 | * | |
644 | * Entries without "value", i. e. consisting of only "name" or | |
645 | * "name=", will cause this entry to be deleted from the hash table. | |
646 | * | |
647 | * The "flag" argument can be used to control the behaviour: when the | |
648 | * H_NOCLEAR bit is set, then an existing hash table will kept, i. e. | |
649 | * new data will be added to an existing hash table; otherwise, old | |
650 | * data will be discarded and a new hash table will be created. | |
651 | * | |
652 | * The separator character for the "name=value" pairs can be selected, | |
653 | * so we both support importing from externally stored environment | |
654 | * data (separated by NUL characters) and from plain text files | |
655 | * (entries separated by newline characters). | |
656 | * | |
657 | * To allow for nicely formatted text input, leading white space | |
658 | * (sequences of SPACE and TAB chars) is ignored, and entries starting | |
659 | * (after removal of any leading white space) with a '#' character are | |
660 | * considered comments and ignored. | |
661 | * | |
662 | * [NOTE: this means that a variable name cannot start with a '#' | |
663 | * character.] | |
664 | * | |
665 | * When using a non-NUL separator character, backslash is used as | |
666 | * escape character in the value part, allowing for example for | |
667 | * multi-line values. | |
668 | * | |
669 | * In theory, arbitrary separator characters can be used, but only | |
670 | * '\0' and '\n' have really been tested. | |
671 | */ | |
672 | ||
a6826fbc | 673 | int himport_r(struct hsearch_data *htab, |
348b1f1c | 674 | const char *env, size_t size, const char sep, int flag, |
c5983592 | 675 | int nvars, char * const vars[], int do_apply) |
a6826fbc WD |
676 | { |
677 | char *data, *sp, *dp, *name, *value; | |
d5370feb GF |
678 | char *localvars[nvars]; |
679 | int i; | |
a6826fbc WD |
680 | |
681 | /* Test for correct arguments. */ | |
682 | if (htab == NULL) { | |
683 | __set_errno(EINVAL); | |
684 | return 0; | |
685 | } | |
686 | ||
687 | /* we allocate new space to make sure we can write to the array */ | |
688 | if ((data = malloc(size)) == NULL) { | |
ff856286 | 689 | debug("himport_r: can't malloc %zu bytes\n", size); |
a6826fbc WD |
690 | __set_errno(ENOMEM); |
691 | return 0; | |
692 | } | |
693 | memcpy(data, env, size); | |
694 | dp = data; | |
695 | ||
d5370feb GF |
696 | /* make a local copy of the list of variables */ |
697 | if (nvars) | |
698 | memcpy(localvars, vars, sizeof(vars[0]) * nvars); | |
699 | ||
a6826fbc WD |
700 | if ((flag & H_NOCLEAR) == 0) { |
701 | /* Destroy old hash table if one exists */ | |
702 | debug("Destroy Hash Table: %p table = %p\n", htab, | |
703 | htab->table); | |
704 | if (htab->table) | |
152874b6 | 705 | hdestroy_r(htab, do_apply); |
a6826fbc WD |
706 | } |
707 | ||
708 | /* | |
709 | * Create new hash table (if needed). The computation of the hash | |
710 | * table size is based on heuristics: in a sample of some 70+ | |
711 | * existing systems we found an average size of 39+ bytes per entry | |
712 | * in the environment (for the whole key=value pair). Assuming a | |
ea882baf WD |
713 | * size of 8 per entry (= safety factor of ~5) should provide enough |
714 | * safety margin for any existing environment definitions and still | |
a6826fbc WD |
715 | * allow for more than enough dynamic additions. Note that the |
716 | * "size" argument is supposed to give the maximum enviroment size | |
ea882baf WD |
717 | * (CONFIG_ENV_SIZE). This heuristics will result in |
718 | * unreasonably large numbers (and thus memory footprint) for | |
719 | * big flash environments (>8,000 entries for 64 KB | |
fc5fc76b AB |
720 | * envrionment size), so we clip it to a reasonable value. |
721 | * On the other hand we need to add some more entries for free | |
722 | * space when importing very small buffers. Both boundaries can | |
723 | * be overwritten in the board config file if needed. | |
a6826fbc WD |
724 | */ |
725 | ||
726 | if (!htab->table) { | |
fc5fc76b | 727 | int nent = CONFIG_ENV_MIN_ENTRIES + size / 8; |
ea882baf WD |
728 | |
729 | if (nent > CONFIG_ENV_MAX_ENTRIES) | |
730 | nent = CONFIG_ENV_MAX_ENTRIES; | |
a6826fbc WD |
731 | |
732 | debug("Create Hash Table: N=%d\n", nent); | |
733 | ||
734 | if (hcreate_r(nent, htab) == 0) { | |
735 | free(data); | |
736 | return 0; | |
737 | } | |
738 | } | |
739 | ||
740 | /* Parse environment; allow for '\0' and 'sep' as separators */ | |
741 | do { | |
742 | ENTRY e, *rv; | |
743 | ||
744 | /* skip leading white space */ | |
4d91a6ec | 745 | while (isblank(*dp)) |
a6826fbc WD |
746 | ++dp; |
747 | ||
748 | /* skip comment lines */ | |
749 | if (*dp == '#') { | |
750 | while (*dp && (*dp != sep)) | |
751 | ++dp; | |
752 | ++dp; | |
753 | continue; | |
754 | } | |
755 | ||
756 | /* parse name */ | |
757 | for (name = dp; *dp != '=' && *dp && *dp != sep; ++dp) | |
758 | ; | |
759 | ||
760 | /* deal with "name" and "name=" entries (delete var) */ | |
761 | if (*dp == '\0' || *(dp + 1) == '\0' || | |
762 | *dp == sep || *(dp + 1) == sep) { | |
763 | if (*dp == '=') | |
764 | *dp++ = '\0'; | |
765 | *dp++ = '\0'; /* terminate name */ | |
766 | ||
767 | debug("DELETE CANDIDATE: \"%s\"\n", name); | |
d5370feb | 768 | if (!drop_var_from_set(name, nvars, localvars)) |
348b1f1c | 769 | continue; |
a6826fbc | 770 | |
152874b6 | 771 | if (hdelete_r(name, htab, do_apply) == 0) |
a6826fbc WD |
772 | debug("DELETE ERROR ##############################\n"); |
773 | ||
774 | continue; | |
775 | } | |
776 | *dp++ = '\0'; /* terminate name */ | |
777 | ||
778 | /* parse value; deal with escapes */ | |
779 | for (value = sp = dp; *dp && (*dp != sep); ++dp) { | |
780 | if ((*dp == '\\') && *(dp + 1)) | |
781 | ++dp; | |
782 | *sp++ = *dp; | |
783 | } | |
784 | *sp++ = '\0'; /* terminate value */ | |
785 | ++dp; | |
786 | ||
348b1f1c | 787 | /* Skip variables which are not supposed to be processed */ |
d5370feb | 788 | if (!drop_var_from_set(name, nvars, localvars)) |
348b1f1c GF |
789 | continue; |
790 | ||
a6826fbc WD |
791 | /* enter into hash table */ |
792 | e.key = name; | |
793 | e.data = value; | |
794 | ||
c5983592 GF |
795 | /* if there is an apply function, check what it has to say */ |
796 | if (do_apply && htab->apply != NULL) { | |
797 | debug("searching before calling cb function" | |
798 | " for %s\n", name); | |
799 | /* | |
800 | * Search for variable in existing env, so to pass | |
801 | * its previous value to the apply callback | |
802 | */ | |
803 | hsearch_r(e, FIND, &rv, htab); | |
804 | debug("previous value was %s\n", rv ? rv->data : ""); | |
805 | if (htab->apply(name, rv ? rv->data : NULL, | |
806 | value, flag)) { | |
807 | debug("callback function refused to set" | |
808 | " variable %s, skipping it!\n", name); | |
809 | continue; | |
810 | } | |
811 | } | |
812 | ||
a6826fbc WD |
813 | hsearch_r(e, ENTER, &rv, htab); |
814 | if (rv == NULL) { | |
ea882baf WD |
815 | printf("himport_r: can't insert \"%s=%s\" into hash table\n", |
816 | name, value); | |
a6826fbc WD |
817 | return 0; |
818 | } | |
819 | ||
ea882baf WD |
820 | debug("INSERT: table %p, filled %d/%d rv %p ==> name=\"%s\" value=\"%s\"\n", |
821 | htab, htab->filled, htab->size, | |
822 | rv, name, value); | |
a6826fbc WD |
823 | } while ((dp < data + size) && *dp); /* size check needed for text */ |
824 | /* without '\0' termination */ | |
ea882baf | 825 | debug("INSERT: free(data = %p)\n", data); |
a6826fbc WD |
826 | free(data); |
827 | ||
d5370feb GF |
828 | /* process variables which were not considered */ |
829 | for (i = 0; i < nvars; i++) { | |
830 | if (localvars[i] == NULL) | |
831 | continue; | |
832 | /* | |
833 | * All variables which were not deleted from the variable list | |
834 | * were not present in the imported env | |
835 | * This could mean two things: | |
836 | * a) if the variable was present in current env, we delete it | |
837 | * b) if the variable was not present in current env, we notify | |
838 | * it might be a typo | |
839 | */ | |
840 | if (hdelete_r(localvars[i], htab, do_apply) == 0) | |
841 | printf("WARNING: '%s' neither in running nor in imported env!\n", localvars[i]); | |
842 | else | |
843 | printf("WARNING: '%s' not in imported env, deleting it!\n", localvars[i]); | |
844 | } | |
845 | ||
ea882baf | 846 | debug("INSERT: done\n"); |
a6826fbc WD |
847 | return 1; /* everything OK */ |
848 | } |