blob: 07ebfb218f8a6f152d915e448a2c2304a53b9f02 [file] [log] [blame]
Wolfgang Denka6826fb2010-06-20 13:17:12 +02001/*
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>
Jason Hobbs4d91a6e2011-08-23 11:06:54 +000035# include <ctype.h>
Wolfgang Denka6826fb2010-06-20 13:17:12 +020036
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>
Jason Hobbs4d91a6e2011-08-23 11:06:54 +000047# include <linux/ctype.h>
Wolfgang Denka6826fb2010-06-20 13:17:12 +020048#endif
49
Andreas Bießmannfc5fc762010-10-01 22:51:02 +020050#ifndef CONFIG_ENV_MIN_ENTRIES /* minimum number of entries */
51#define CONFIG_ENV_MIN_ENTRIES 64
52#endif
Wolfgang Denkea882ba2010-06-20 23:33:59 +020053#ifndef CONFIG_ENV_MAX_ENTRIES /* maximum number of entries */
54#define CONFIG_ENV_MAX_ENTRIES 512
55#endif
56
Joe Hershberger170ab112012-12-11 22:16:24 -060057#include <env_callback.h>
Joe Hershberger25980902012-12-11 22:16:31 -060058#include <env_flags.h>
Joe Hershberger170ab112012-12-11 22:16:24 -060059#include <search.h>
Wolfgang Denka6826fb2010-06-20 13:17:12 +020060
61/*
62 * [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986
Wolfgang Denk071bc922010-10-27 22:48:30 +020063 * [Knuth] The Art of Computer Programming, part 3 (6.4)
Wolfgang Denka6826fb2010-06-20 13:17:12 +020064 */
65
66/*
Wolfgang Denka6826fb2010-06-20 13:17:12 +020067 * The reentrant version has no static variables to maintain the state.
68 * Instead the interface of all functions is extended to take an argument
69 * which describes the current status.
70 */
Joe Hershberger7afcf3a2012-12-11 22:16:21 -060071
Wolfgang Denka6826fb2010-06-20 13:17:12 +020072typedef struct _ENTRY {
Peter Baradac81c1222011-03-21 19:05:20 -040073 int used;
Wolfgang Denka6826fb2010-06-20 13:17:12 +020074 ENTRY entry;
75} _ENTRY;
76
77
Joe Hershberger7afcf3a2012-12-11 22:16:21 -060078static void _hdelete(const char *key, struct hsearch_data *htab, ENTRY *ep,
79 int idx);
80
Wolfgang Denka6826fb2010-06-20 13:17:12 +020081/*
82 * hcreate()
83 */
84
85/*
86 * For the used double hash method the table size has to be a prime. To
87 * correct the user given table size we need a prime test. This trivial
88 * algorithm is adequate because
89 * a) the code is (most probably) called a few times per program run and
90 * b) the number is small because the table must fit in the core
91 * */
92static int isprime(unsigned int number)
93{
94 /* no even number will be passed */
95 unsigned int div = 3;
96
97 while (div * div < number && number % div != 0)
98 div += 2;
99
100 return number % div != 0;
101}
102
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200103/*
104 * Before using the hash table we must allocate memory for it.
105 * Test for an existing table are done. We allocate one element
106 * more as the found prime number says. This is done for more effective
107 * indexing as explained in the comment for the hsearch function.
108 * The contents of the table is zeroed, especially the field used
109 * becomes zero.
110 */
Mike Frysinger2eb15732010-12-08 06:26:04 -0500111
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200112int hcreate_r(size_t nel, struct hsearch_data *htab)
113{
114 /* Test for correct arguments. */
115 if (htab == NULL) {
116 __set_errno(EINVAL);
117 return 0;
118 }
119
120 /* There is still another table active. Return with error. */
121 if (htab->table != NULL)
122 return 0;
123
124 /* Change nel to the first prime number not smaller as nel. */
125 nel |= 1; /* make odd */
126 while (!isprime(nel))
127 nel += 2;
128
129 htab->size = nel;
130 htab->filled = 0;
131
132 /* allocate memory and zero out */
133 htab->table = (_ENTRY *) calloc(htab->size + 1, sizeof(_ENTRY));
134 if (htab->table == NULL)
135 return 0;
136
137 /* everything went alright */
138 return 1;
139}
140
141
142/*
143 * hdestroy()
144 */
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200145
146/*
147 * After using the hash table it has to be destroyed. The used memory can
148 * be freed and the local static variable can be marked as not used.
149 */
Mike Frysinger2eb15732010-12-08 06:26:04 -0500150
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600151void hdestroy_r(struct hsearch_data *htab)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200152{
153 int i;
154
155 /* Test for correct arguments. */
156 if (htab == NULL) {
157 __set_errno(EINVAL);
158 return;
159 }
160
161 /* free used memory */
162 for (i = 1; i <= htab->size; ++i) {
Peter Baradac81c1222011-03-21 19:05:20 -0400163 if (htab->table[i].used > 0) {
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200164 ENTRY *ep = &htab->table[i].entry;
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600165
Wolfgang Denk84b5e802011-07-29 14:42:18 +0200166 free((void *)ep->key);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200167 free(ep->data);
168 }
169 }
170 free(htab->table);
171
172 /* the sign for an existing table is an value != NULL in htable */
173 htab->table = NULL;
174}
175
176/*
177 * hsearch()
178 */
179
180/*
181 * This is the search function. It uses double hashing with open addressing.
182 * The argument item.key has to be a pointer to an zero terminated, most
183 * probably strings of chars. The function for generating a number of the
184 * strings is simple but fast. It can be replaced by a more complex function
185 * like ajw (see [Aho,Sethi,Ullman]) if the needs are shown.
186 *
187 * We use an trick to speed up the lookup. The table is created by hcreate
188 * with one more element available. This enables us to use the index zero
189 * special. This index will never be used because we store the first hash
190 * index in the field used where zero means not used. Every other value
191 * means used. The used field can be used as a first fast comparison for
192 * equality of the stored and the parameter value. This helps to prevent
193 * unnecessary expensive calls of strcmp.
194 *
195 * This implementation differs from the standard library version of
196 * this function in a number of ways:
197 *
198 * - While the standard version does not make any assumptions about
199 * the type of the stored data objects at all, this implementation
200 * works with NUL terminated strings only.
201 * - Instead of storing just pointers to the original objects, we
202 * create local copies so the caller does not need to care about the
203 * data any more.
204 * - The standard implementation does not provide a way to update an
205 * existing entry. This version will create a new entry or update an
206 * existing one when both "action == ENTER" and "item.data != NULL".
207 * - Instead of returning 1 on success, we return the index into the
208 * internal hash table, which is also guaranteed to be positive.
209 * This allows us direct access to the found hash table slot for
210 * example for functions like hdelete().
211 */
212
Kim Phillipsa000b792011-04-05 07:15:14 +0000213/*
214 * hstrstr_r - return index to entry whose key and/or data contains match
215 */
216int hstrstr_r(const char *match, int last_idx, ENTRY ** retval,
217 struct hsearch_data *htab)
218{
219 unsigned int idx;
220
221 for (idx = last_idx + 1; idx < htab->size; ++idx) {
222 if (htab->table[idx].used <= 0)
223 continue;
224 if (strstr(htab->table[idx].entry.key, match) ||
225 strstr(htab->table[idx].entry.data, match)) {
226 *retval = &htab->table[idx].entry;
227 return idx;
228 }
229 }
230
231 __set_errno(ESRCH);
232 *retval = NULL;
233 return 0;
234}
235
Mike Frysinger560d4242010-12-17 16:51:59 -0500236int hmatch_r(const char *match, int last_idx, ENTRY ** retval,
237 struct hsearch_data *htab)
238{
239 unsigned int idx;
240 size_t key_len = strlen(match);
241
242 for (idx = last_idx + 1; idx < htab->size; ++idx) {
Kim Phillipsaf4d9072011-04-04 15:17:45 +0000243 if (htab->table[idx].used <= 0)
Mike Frysinger560d4242010-12-17 16:51:59 -0500244 continue;
245 if (!strncmp(match, htab->table[idx].entry.key, key_len)) {
246 *retval = &htab->table[idx].entry;
247 return idx;
248 }
249 }
250
251 __set_errno(ESRCH);
252 *retval = NULL;
253 return 0;
254}
255
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600256/*
257 * Compare an existing entry with the desired key, and overwrite if the action
258 * is ENTER. This is simply a helper function for hsearch_r().
259 */
260static inline int _compare_and_overwrite_entry(ENTRY item, ACTION action,
261 ENTRY **retval, struct hsearch_data *htab, int flag,
262 unsigned int hval, unsigned int idx)
263{
264 if (htab->table[idx].used == hval
265 && strcmp(item.key, htab->table[idx].entry.key) == 0) {
266 /* Overwrite existing value? */
267 if ((action == ENTER) && (item.data != NULL)) {
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600268 /* check for permission */
269 if (htab->change_ok != NULL && htab->change_ok(
270 &htab->table[idx].entry, item.data,
271 env_op_overwrite, flag)) {
272 debug("change_ok() rejected setting variable "
273 "%s, skipping it!\n", item.key);
274 __set_errno(EPERM);
275 *retval = NULL;
276 return 0;
277 }
278
Joe Hershberger170ab112012-12-11 22:16:24 -0600279 /* If there is a callback, call it */
280 if (htab->table[idx].entry.callback &&
281 htab->table[idx].entry.callback(item.key,
282 item.data, env_op_overwrite, flag)) {
283 debug("callback() rejected setting variable "
284 "%s, skipping it!\n", item.key);
285 __set_errno(EINVAL);
286 *retval = NULL;
287 return 0;
288 }
289
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600290 free(htab->table[idx].entry.data);
291 htab->table[idx].entry.data = strdup(item.data);
292 if (!htab->table[idx].entry.data) {
293 __set_errno(ENOMEM);
294 *retval = NULL;
295 return 0;
296 }
297 }
298 /* return found entry */
299 *retval = &htab->table[idx].entry;
300 return idx;
301 }
302 /* keep searching */
303 return -1;
304}
305
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200306int hsearch_r(ENTRY item, ACTION action, ENTRY ** retval,
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600307 struct hsearch_data *htab, int flag)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200308{
309 unsigned int hval;
310 unsigned int count;
311 unsigned int len = strlen(item.key);
312 unsigned int idx;
Peter Baradac81c1222011-03-21 19:05:20 -0400313 unsigned int first_deleted = 0;
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600314 int ret;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200315
316 /* Compute an value for the given string. Perhaps use a better method. */
317 hval = len;
318 count = len;
319 while (count-- > 0) {
320 hval <<= 4;
321 hval += item.key[count];
322 }
323
324 /*
325 * First hash function:
326 * simply take the modul but prevent zero.
327 */
328 hval %= htab->size;
329 if (hval == 0)
330 ++hval;
331
332 /* The first index tried. */
333 idx = hval;
334
335 if (htab->table[idx].used) {
336 /*
Wolfgang Denk071bc922010-10-27 22:48:30 +0200337 * Further action might be required according to the
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200338 * action value.
339 */
340 unsigned hval2;
341
Peter Baradac81c1222011-03-21 19:05:20 -0400342 if (htab->table[idx].used == -1
343 && !first_deleted)
344 first_deleted = idx;
345
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600346 ret = _compare_and_overwrite_entry(item, action, retval, htab,
347 flag, hval, idx);
348 if (ret != -1)
349 return ret;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200350
351 /*
352 * Second hash function:
353 * as suggested in [Knuth]
354 */
355 hval2 = 1 + hval % (htab->size - 2);
356
357 do {
358 /*
Wolfgang Denk071bc922010-10-27 22:48:30 +0200359 * Because SIZE is prime this guarantees to
360 * step through all available indices.
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200361 */
362 if (idx <= hval2)
363 idx = htab->size + idx - hval2;
364 else
365 idx -= hval2;
366
367 /*
368 * If we visited all entries leave the loop
369 * unsuccessfully.
370 */
371 if (idx == hval)
372 break;
373
374 /* If entry is found use it. */
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600375 ret = _compare_and_overwrite_entry(item, action, retval,
376 htab, flag, hval, idx);
377 if (ret != -1)
378 return ret;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200379 }
380 while (htab->table[idx].used);
381 }
382
383 /* An empty bucket has been found. */
384 if (action == ENTER) {
385 /*
Wolfgang Denk071bc922010-10-27 22:48:30 +0200386 * If table is full and another entry should be
387 * entered return with error.
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200388 */
389 if (htab->filled == htab->size) {
390 __set_errno(ENOMEM);
391 *retval = NULL;
392 return 0;
393 }
394
395 /*
396 * Create new entry;
397 * create copies of item.key and item.data
398 */
Peter Baradac81c1222011-03-21 19:05:20 -0400399 if (first_deleted)
400 idx = first_deleted;
401
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200402 htab->table[idx].used = hval;
403 htab->table[idx].entry.key = strdup(item.key);
404 htab->table[idx].entry.data = strdup(item.data);
405 if (!htab->table[idx].entry.key ||
406 !htab->table[idx].entry.data) {
407 __set_errno(ENOMEM);
408 *retval = NULL;
409 return 0;
410 }
411
412 ++htab->filled;
413
Joe Hershberger170ab112012-12-11 22:16:24 -0600414 /* This is a new entry, so look up a possible callback */
415 env_callback_init(&htab->table[idx].entry);
Joe Hershberger25980902012-12-11 22:16:31 -0600416 /* Also look for flags */
417 env_flags_init(&htab->table[idx].entry);
Joe Hershberger170ab112012-12-11 22:16:24 -0600418
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600419 /* check for permission */
420 if (htab->change_ok != NULL && htab->change_ok(
421 &htab->table[idx].entry, item.data, env_op_create, flag)) {
422 debug("change_ok() rejected setting variable "
423 "%s, skipping it!\n", item.key);
424 _hdelete(item.key, htab, &htab->table[idx].entry, idx);
425 __set_errno(EPERM);
426 *retval = NULL;
427 return 0;
428 }
429
Joe Hershberger170ab112012-12-11 22:16:24 -0600430 /* If there is a callback, call it */
431 if (htab->table[idx].entry.callback &&
432 htab->table[idx].entry.callback(item.key, item.data,
433 env_op_create, flag)) {
434 debug("callback() rejected setting variable "
435 "%s, skipping it!\n", item.key);
436 _hdelete(item.key, htab, &htab->table[idx].entry, idx);
437 __set_errno(EINVAL);
438 *retval = NULL;
439 return 0;
440 }
441
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200442 /* return new entry */
443 *retval = &htab->table[idx].entry;
444 return 1;
445 }
446
447 __set_errno(ESRCH);
448 *retval = NULL;
449 return 0;
450}
451
452
453/*
454 * hdelete()
455 */
456
457/*
458 * The standard implementation of hsearch(3) does not provide any way
459 * to delete any entries from the hash table. We extend the code to
460 * do that.
461 */
462
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600463static void _hdelete(const char *key, struct hsearch_data *htab, ENTRY *ep,
464 int idx)
465{
466 /* free used ENTRY */
467 debug("hdelete: DELETING key \"%s\"\n", key);
468 free((void *)ep->key);
469 free(ep->data);
Joe Hershberger170ab112012-12-11 22:16:24 -0600470 ep->callback = NULL;
Joe Hershberger25980902012-12-11 22:16:31 -0600471 ep->flags = 0;
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600472 htab->table[idx].used = -1;
473
474 --htab->filled;
475}
476
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600477int hdelete_r(const char *key, struct hsearch_data *htab, int flag)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200478{
479 ENTRY e, *ep;
480 int idx;
481
482 debug("hdelete: DELETE key \"%s\"\n", key);
483
484 e.key = (char *)key;
485
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600486 idx = hsearch_r(e, FIND, &ep, htab, 0);
487 if (idx == 0) {
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200488 __set_errno(ESRCH);
489 return 0; /* not found */
490 }
491
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600492 /* Check for permission */
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600493 if (htab->change_ok != NULL &&
494 htab->change_ok(ep, NULL, env_op_delete, flag)) {
495 debug("change_ok() rejected deleting variable "
496 "%s, skipping it!\n", key);
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600497 __set_errno(EPERM);
498 return 0;
499 }
500
Joe Hershberger170ab112012-12-11 22:16:24 -0600501 /* If there is a callback, call it */
502 if (htab->table[idx].entry.callback &&
503 htab->table[idx].entry.callback(key, NULL, env_op_delete, flag)) {
504 debug("callback() rejected deleting variable "
505 "%s, skipping it!\n", key);
506 __set_errno(EINVAL);
507 return 0;
508 }
509
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600510 _hdelete(key, htab, ep, idx);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200511
512 return 1;
513}
514
515/*
516 * hexport()
517 */
518
Ilya Yanok7ac2fe22012-09-18 00:22:50 +0000519#ifndef CONFIG_SPL_BUILD
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200520/*
521 * Export the data stored in the hash table in linearized form.
522 *
523 * Entries are exported as "name=value" strings, separated by an
524 * arbitrary (non-NUL, of course) separator character. This allows to
525 * use this function both when formatting the U-Boot environment for
526 * external storage (using '\0' as separator), but also when using it
527 * for the "printenv" command to print all variables, simply by using
528 * as '\n" as separator. This can also be used for new features like
529 * exporting the environment data as text file, including the option
530 * for later re-import.
531 *
532 * The entries in the result list will be sorted by ascending key
533 * values.
534 *
535 * If the separator character is different from NUL, then any
536 * separator characters and backslash characters in the values will
537 * be escaped by a preceeding backslash in output. This is needed for
538 * example to enable multi-line values, especially when the output
539 * shall later be parsed (for example, for re-import).
540 *
541 * There are several options how the result buffer is handled:
542 *
543 * *resp size
544 * -----------
545 * NULL 0 A string of sufficient length will be allocated.
546 * NULL >0 A string of the size given will be
547 * allocated. An error will be returned if the size is
548 * not sufficient. Any unused bytes in the string will
549 * be '\0'-padded.
550 * !NULL 0 The user-supplied buffer will be used. No length
551 * checking will be performed, i. e. it is assumed that
552 * the buffer size will always be big enough. DANGEROUS.
553 * !NULL >0 The user-supplied buffer will be used. An error will
554 * be returned if the size is not sufficient. Any unused
555 * bytes in the string will be '\0'-padded.
556 */
557
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200558static int cmpkey(const void *p1, const void *p2)
559{
560 ENTRY *e1 = *(ENTRY **) p1;
561 ENTRY *e2 = *(ENTRY **) p2;
562
563 return (strcmp(e1->key, e2->key));
564}
565
Joe Hershbergerbe112352012-12-11 22:16:23 -0600566ssize_t hexport_r(struct hsearch_data *htab, const char sep, int flag,
Wolfgang Denk37f2fe72011-11-06 22:49:44 +0100567 char **resp, size_t size,
568 int argc, char * const argv[])
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200569{
570 ENTRY *list[htab->size];
571 char *res, *p;
572 size_t totlen;
573 int i, n;
574
575 /* Test for correct arguments. */
576 if ((resp == NULL) || (htab == NULL)) {
577 __set_errno(EINVAL);
578 return (-1);
579 }
580
Simon Glassff856282011-11-21 19:04:23 +0000581 debug("EXPORT table = %p, htab.size = %d, htab.filled = %d, "
582 "size = %zu\n", htab, htab->size, htab->filled, size);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200583 /*
584 * Pass 1:
585 * search used entries,
586 * save addresses and compute total length
587 */
588 for (i = 1, n = 0, totlen = 0; i <= htab->size; ++i) {
589
Peter Baradac81c1222011-03-21 19:05:20 -0400590 if (htab->table[i].used > 0) {
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200591 ENTRY *ep = &htab->table[i].entry;
Wolfgang Denk37f2fe72011-11-06 22:49:44 +0100592 int arg, found = 0;
593
594 for (arg = 0; arg < argc; ++arg) {
595 if (strcmp(argv[arg], ep->key) == 0) {
596 found = 1;
597 break;
598 }
599 }
600 if ((argc > 0) && (found == 0))
601 continue;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200602
Joe Hershbergerbe112352012-12-11 22:16:23 -0600603 if ((flag & H_HIDE_DOT) && ep->key[0] == '.')
604 continue;
605
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200606 list[n++] = ep;
607
608 totlen += strlen(ep->key) + 2;
609
610 if (sep == '\0') {
611 totlen += strlen(ep->data);
612 } else { /* check if escapes are needed */
613 char *s = ep->data;
614
615 while (*s) {
616 ++totlen;
617 /* add room for needed escape chars */
618 if ((*s == sep) || (*s == '\\'))
619 ++totlen;
620 ++s;
621 }
622 }
623 totlen += 2; /* for '=' and 'sep' char */
624 }
625 }
626
627#ifdef DEBUG
628 /* Pass 1a: print unsorted list */
629 printf("Unsorted: n=%d\n", n);
630 for (i = 0; i < n; ++i) {
631 printf("\t%3d: %p ==> %-10s => %s\n",
632 i, list[i], list[i]->key, list[i]->data);
633 }
634#endif
635
636 /* Sort list by keys */
637 qsort(list, n, sizeof(ENTRY *), cmpkey);
638
639 /* Check if the user supplied buffer size is sufficient */
640 if (size) {
641 if (size < totlen + 1) { /* provided buffer too small */
Simon Glassff856282011-11-21 19:04:23 +0000642 printf("Env export buffer too small: %zu, "
643 "but need %zu\n", size, totlen + 1);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200644 __set_errno(ENOMEM);
645 return (-1);
646 }
647 } else {
648 size = totlen + 1;
649 }
650
651 /* Check if the user provided a buffer */
652 if (*resp) {
653 /* yes; clear it */
654 res = *resp;
655 memset(res, '\0', size);
656 } else {
657 /* no, allocate and clear one */
658 *resp = res = calloc(1, size);
659 if (res == NULL) {
660 __set_errno(ENOMEM);
661 return (-1);
662 }
663 }
664 /*
665 * Pass 2:
666 * export sorted list of result data
667 */
668 for (i = 0, p = res; i < n; ++i) {
Wolfgang Denk84b5e802011-07-29 14:42:18 +0200669 const char *s;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200670
671 s = list[i]->key;
672 while (*s)
673 *p++ = *s++;
674 *p++ = '=';
675
676 s = list[i]->data;
677
678 while (*s) {
679 if ((*s == sep) || (*s == '\\'))
680 *p++ = '\\'; /* escape */
681 *p++ = *s++;
682 }
683 *p++ = sep;
684 }
685 *p = '\0'; /* terminate result */
686
687 return size;
688}
Ilya Yanok7ac2fe22012-09-18 00:22:50 +0000689#endif
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200690
691
692/*
693 * himport()
694 */
695
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000696/*
697 * Check whether variable 'name' is amongst vars[],
698 * and remove all instances by setting the pointer to NULL
699 */
700static int drop_var_from_set(const char *name, int nvars, char * vars[])
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000701{
702 int i = 0;
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000703 int res = 0;
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000704
705 /* No variables specified means process all of them */
706 if (nvars == 0)
707 return 1;
708
709 for (i = 0; i < nvars; i++) {
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000710 if (vars[i] == NULL)
711 continue;
712 /* If we found it, delete all of them */
713 if (!strcmp(name, vars[i])) {
714 vars[i] = NULL;
715 res = 1;
716 }
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000717 }
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000718 if (!res)
719 debug("Skipping non-listed variable %s\n", name);
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000720
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000721 return res;
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000722}
723
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200724/*
725 * Import linearized data into hash table.
726 *
727 * This is the inverse function to hexport(): it takes a linear list
728 * of "name=value" pairs and creates hash table entries from it.
729 *
730 * Entries without "value", i. e. consisting of only "name" or
731 * "name=", will cause this entry to be deleted from the hash table.
732 *
733 * The "flag" argument can be used to control the behaviour: when the
734 * H_NOCLEAR bit is set, then an existing hash table will kept, i. e.
735 * new data will be added to an existing hash table; otherwise, old
736 * data will be discarded and a new hash table will be created.
737 *
738 * The separator character for the "name=value" pairs can be selected,
739 * so we both support importing from externally stored environment
740 * data (separated by NUL characters) and from plain text files
741 * (entries separated by newline characters).
742 *
743 * To allow for nicely formatted text input, leading white space
744 * (sequences of SPACE and TAB chars) is ignored, and entries starting
745 * (after removal of any leading white space) with a '#' character are
746 * considered comments and ignored.
747 *
748 * [NOTE: this means that a variable name cannot start with a '#'
749 * character.]
750 *
751 * When using a non-NUL separator character, backslash is used as
752 * escape character in the value part, allowing for example for
753 * multi-line values.
754 *
755 * In theory, arbitrary separator characters can be used, but only
756 * '\0' and '\n' have really been tested.
757 */
758
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200759int himport_r(struct hsearch_data *htab,
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000760 const char *env, size_t size, const char sep, int flag,
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600761 int nvars, char * const vars[])
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200762{
763 char *data, *sp, *dp, *name, *value;
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000764 char *localvars[nvars];
765 int i;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200766
767 /* Test for correct arguments. */
768 if (htab == NULL) {
769 __set_errno(EINVAL);
770 return 0;
771 }
772
773 /* we allocate new space to make sure we can write to the array */
774 if ((data = malloc(size)) == NULL) {
Simon Glassff856282011-11-21 19:04:23 +0000775 debug("himport_r: can't malloc %zu bytes\n", size);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200776 __set_errno(ENOMEM);
777 return 0;
778 }
779 memcpy(data, env, size);
780 dp = data;
781
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000782 /* make a local copy of the list of variables */
783 if (nvars)
784 memcpy(localvars, vars, sizeof(vars[0]) * nvars);
785
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200786 if ((flag & H_NOCLEAR) == 0) {
787 /* Destroy old hash table if one exists */
788 debug("Destroy Hash Table: %p table = %p\n", htab,
789 htab->table);
790 if (htab->table)
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600791 hdestroy_r(htab);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200792 }
793
794 /*
795 * Create new hash table (if needed). The computation of the hash
796 * table size is based on heuristics: in a sample of some 70+
797 * existing systems we found an average size of 39+ bytes per entry
798 * in the environment (for the whole key=value pair). Assuming a
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200799 * size of 8 per entry (= safety factor of ~5) should provide enough
800 * safety margin for any existing environment definitions and still
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200801 * allow for more than enough dynamic additions. Note that the
802 * "size" argument is supposed to give the maximum enviroment size
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200803 * (CONFIG_ENV_SIZE). This heuristics will result in
804 * unreasonably large numbers (and thus memory footprint) for
805 * big flash environments (>8,000 entries for 64 KB
Andreas Bießmannfc5fc762010-10-01 22:51:02 +0200806 * envrionment size), so we clip it to a reasonable value.
807 * On the other hand we need to add some more entries for free
808 * space when importing very small buffers. Both boundaries can
809 * be overwritten in the board config file if needed.
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200810 */
811
812 if (!htab->table) {
Andreas Bießmannfc5fc762010-10-01 22:51:02 +0200813 int nent = CONFIG_ENV_MIN_ENTRIES + size / 8;
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200814
815 if (nent > CONFIG_ENV_MAX_ENTRIES)
816 nent = CONFIG_ENV_MAX_ENTRIES;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200817
818 debug("Create Hash Table: N=%d\n", nent);
819
820 if (hcreate_r(nent, htab) == 0) {
821 free(data);
822 return 0;
823 }
824 }
825
826 /* Parse environment; allow for '\0' and 'sep' as separators */
827 do {
828 ENTRY e, *rv;
829
830 /* skip leading white space */
Jason Hobbs4d91a6e2011-08-23 11:06:54 +0000831 while (isblank(*dp))
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200832 ++dp;
833
834 /* skip comment lines */
835 if (*dp == '#') {
836 while (*dp && (*dp != sep))
837 ++dp;
838 ++dp;
839 continue;
840 }
841
842 /* parse name */
843 for (name = dp; *dp != '=' && *dp && *dp != sep; ++dp)
844 ;
845
846 /* deal with "name" and "name=" entries (delete var) */
847 if (*dp == '\0' || *(dp + 1) == '\0' ||
848 *dp == sep || *(dp + 1) == sep) {
849 if (*dp == '=')
850 *dp++ = '\0';
851 *dp++ = '\0'; /* terminate name */
852
853 debug("DELETE CANDIDATE: \"%s\"\n", name);
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000854 if (!drop_var_from_set(name, nvars, localvars))
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000855 continue;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200856
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600857 if (hdelete_r(name, htab, flag) == 0)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200858 debug("DELETE ERROR ##############################\n");
859
860 continue;
861 }
862 *dp++ = '\0'; /* terminate name */
863
864 /* parse value; deal with escapes */
865 for (value = sp = dp; *dp && (*dp != sep); ++dp) {
866 if ((*dp == '\\') && *(dp + 1))
867 ++dp;
868 *sp++ = *dp;
869 }
870 *sp++ = '\0'; /* terminate value */
871 ++dp;
872
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000873 /* Skip variables which are not supposed to be processed */
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000874 if (!drop_var_from_set(name, nvars, localvars))
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000875 continue;
876
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200877 /* enter into hash table */
878 e.key = name;
879 e.data = value;
880
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600881 hsearch_r(e, ENTER, &rv, htab, flag);
Joe Hershberger170ab112012-12-11 22:16:24 -0600882 if (rv == NULL)
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200883 printf("himport_r: can't insert \"%s=%s\" into hash table\n",
884 name, value);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200885
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200886 debug("INSERT: table %p, filled %d/%d rv %p ==> name=\"%s\" value=\"%s\"\n",
887 htab, htab->filled, htab->size,
888 rv, name, value);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200889 } while ((dp < data + size) && *dp); /* size check needed for text */
890 /* without '\0' termination */
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200891 debug("INSERT: free(data = %p)\n", data);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200892 free(data);
893
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000894 /* process variables which were not considered */
895 for (i = 0; i < nvars; i++) {
896 if (localvars[i] == NULL)
897 continue;
898 /*
899 * All variables which were not deleted from the variable list
900 * were not present in the imported env
901 * This could mean two things:
902 * a) if the variable was present in current env, we delete it
903 * b) if the variable was not present in current env, we notify
904 * it might be a typo
905 */
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600906 if (hdelete_r(localvars[i], htab, flag) == 0)
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000907 printf("WARNING: '%s' neither in running nor in imported env!\n", localvars[i]);
908 else
909 printf("WARNING: '%s' not in imported env, deleting it!\n", localvars[i]);
910 }
911
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200912 debug("INSERT: done\n");
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200913 return 1; /* everything OK */
914}
Joe Hershberger170ab112012-12-11 22:16:24 -0600915
916/*
917 * hwalk_r()
918 */
919
920/*
921 * Walk all of the entries in the hash, calling the callback for each one.
922 * this allows some generic operation to be performed on each element.
923 */
924int hwalk_r(struct hsearch_data *htab, int (*callback)(ENTRY *))
925{
926 int i;
927 int retval;
928
929 for (i = 1; i <= htab->size; ++i) {
930 if (htab->table[i].used > 0) {
931 retval = callback(&htab->table[i].entry);
932 if (retval)
933 return retval;
934 }
935 }
936
937 return 0;
938}