blob: 644330a17e8ce7a6bdb8f0112094d5c1e884435e [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 *
Wolfgang Denkea009d42013-03-23 23:50:28 +00005 * Copyright (C) 2010-2013 Wolfgang Denk <wd@denx.de>
Wolfgang Denka6826fb2010-06-20 13:17:12 +02006 *
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 *
Wolfgang Denkeee479c2013-07-08 11:48:07 +020013 * SPDX-License-Identifier: LGPL-2.1+
Wolfgang Denka6826fb2010-06-20 13:17:12 +020014 */
15
16#include <errno.h>
17#include <malloc.h>
18
19#ifdef USE_HOSTCC /* HOST build */
20# include <string.h>
21# include <assert.h>
Jason Hobbs4d91a6e2011-08-23 11:06:54 +000022# include <ctype.h>
Wolfgang Denka6826fb2010-06-20 13:17:12 +020023
24# ifndef debug
25# ifdef DEBUG
26# define debug(fmt,args...) printf(fmt ,##args)
27# else
28# define debug(fmt,args...)
29# endif
30# endif
31#else /* U-Boot build */
32# include <common.h>
33# include <linux/string.h>
Jason Hobbs4d91a6e2011-08-23 11:06:54 +000034# include <linux/ctype.h>
Wolfgang Denka6826fb2010-06-20 13:17:12 +020035#endif
36
Andreas Bießmannfc5fc762010-10-01 22:51:02 +020037#ifndef CONFIG_ENV_MIN_ENTRIES /* minimum number of entries */
38#define CONFIG_ENV_MIN_ENTRIES 64
39#endif
Wolfgang Denkea882ba2010-06-20 23:33:59 +020040#ifndef CONFIG_ENV_MAX_ENTRIES /* maximum number of entries */
41#define CONFIG_ENV_MAX_ENTRIES 512
42#endif
43
Joe Hershberger170ab112012-12-11 22:16:24 -060044#include <env_callback.h>
Joe Hershberger25980902012-12-11 22:16:31 -060045#include <env_flags.h>
Joe Hershberger170ab112012-12-11 22:16:24 -060046#include <search.h>
Wolfgang Denkbe29df62013-03-23 23:50:32 +000047#include <slre.h>
Wolfgang Denka6826fb2010-06-20 13:17:12 +020048
49/*
50 * [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986
Wolfgang Denk071bc922010-10-27 22:48:30 +020051 * [Knuth] The Art of Computer Programming, part 3 (6.4)
Wolfgang Denka6826fb2010-06-20 13:17:12 +020052 */
53
54/*
Wolfgang Denka6826fb2010-06-20 13:17:12 +020055 * The reentrant version has no static variables to maintain the state.
56 * Instead the interface of all functions is extended to take an argument
57 * which describes the current status.
58 */
Joe Hershberger7afcf3a2012-12-11 22:16:21 -060059
Wolfgang Denka6826fb2010-06-20 13:17:12 +020060typedef struct _ENTRY {
Peter Baradac81c1222011-03-21 19:05:20 -040061 int used;
Wolfgang Denka6826fb2010-06-20 13:17:12 +020062 ENTRY entry;
63} _ENTRY;
64
65
Joe Hershberger7afcf3a2012-12-11 22:16:21 -060066static void _hdelete(const char *key, struct hsearch_data *htab, ENTRY *ep,
67 int idx);
68
Wolfgang Denka6826fb2010-06-20 13:17:12 +020069/*
70 * hcreate()
71 */
72
73/*
74 * For the used double hash method the table size has to be a prime. To
75 * correct the user given table size we need a prime test. This trivial
76 * algorithm is adequate because
77 * a) the code is (most probably) called a few times per program run and
78 * b) the number is small because the table must fit in the core
79 * */
80static int isprime(unsigned int number)
81{
82 /* no even number will be passed */
83 unsigned int div = 3;
84
85 while (div * div < number && number % div != 0)
86 div += 2;
87
88 return number % div != 0;
89}
90
Wolfgang Denka6826fb2010-06-20 13:17:12 +020091/*
92 * Before using the hash table we must allocate memory for it.
93 * Test for an existing table are done. We allocate one element
94 * more as the found prime number says. This is done for more effective
95 * indexing as explained in the comment for the hsearch function.
96 * The contents of the table is zeroed, especially the field used
97 * becomes zero.
98 */
Mike Frysinger2eb15732010-12-08 06:26:04 -050099
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200100int hcreate_r(size_t nel, struct hsearch_data *htab)
101{
102 /* Test for correct arguments. */
103 if (htab == NULL) {
104 __set_errno(EINVAL);
105 return 0;
106 }
107
108 /* There is still another table active. Return with error. */
109 if (htab->table != NULL)
110 return 0;
111
112 /* Change nel to the first prime number not smaller as nel. */
113 nel |= 1; /* make odd */
114 while (!isprime(nel))
115 nel += 2;
116
117 htab->size = nel;
118 htab->filled = 0;
119
120 /* allocate memory and zero out */
121 htab->table = (_ENTRY *) calloc(htab->size + 1, sizeof(_ENTRY));
122 if (htab->table == NULL)
123 return 0;
124
125 /* everything went alright */
126 return 1;
127}
128
129
130/*
131 * hdestroy()
132 */
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200133
134/*
135 * After using the hash table it has to be destroyed. The used memory can
136 * be freed and the local static variable can be marked as not used.
137 */
Mike Frysinger2eb15732010-12-08 06:26:04 -0500138
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600139void hdestroy_r(struct hsearch_data *htab)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200140{
141 int i;
142
143 /* Test for correct arguments. */
144 if (htab == NULL) {
145 __set_errno(EINVAL);
146 return;
147 }
148
149 /* free used memory */
150 for (i = 1; i <= htab->size; ++i) {
Peter Baradac81c1222011-03-21 19:05:20 -0400151 if (htab->table[i].used > 0) {
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200152 ENTRY *ep = &htab->table[i].entry;
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600153
Wolfgang Denk84b5e802011-07-29 14:42:18 +0200154 free((void *)ep->key);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200155 free(ep->data);
156 }
157 }
158 free(htab->table);
159
160 /* the sign for an existing table is an value != NULL in htable */
161 htab->table = NULL;
162}
163
164/*
165 * hsearch()
166 */
167
168/*
169 * This is the search function. It uses double hashing with open addressing.
170 * The argument item.key has to be a pointer to an zero terminated, most
171 * probably strings of chars. The function for generating a number of the
172 * strings is simple but fast. It can be replaced by a more complex function
173 * like ajw (see [Aho,Sethi,Ullman]) if the needs are shown.
174 *
175 * We use an trick to speed up the lookup. The table is created by hcreate
176 * with one more element available. This enables us to use the index zero
177 * special. This index will never be used because we store the first hash
178 * index in the field used where zero means not used. Every other value
179 * means used. The used field can be used as a first fast comparison for
180 * equality of the stored and the parameter value. This helps to prevent
181 * unnecessary expensive calls of strcmp.
182 *
183 * This implementation differs from the standard library version of
184 * this function in a number of ways:
185 *
186 * - While the standard version does not make any assumptions about
187 * the type of the stored data objects at all, this implementation
188 * works with NUL terminated strings only.
189 * - Instead of storing just pointers to the original objects, we
190 * create local copies so the caller does not need to care about the
191 * data any more.
192 * - The standard implementation does not provide a way to update an
193 * existing entry. This version will create a new entry or update an
194 * existing one when both "action == ENTER" and "item.data != NULL".
195 * - Instead of returning 1 on success, we return the index into the
196 * internal hash table, which is also guaranteed to be positive.
197 * This allows us direct access to the found hash table slot for
198 * example for functions like hdelete().
199 */
200
Mike Frysinger560d4242010-12-17 16:51:59 -0500201int hmatch_r(const char *match, int last_idx, ENTRY ** retval,
202 struct hsearch_data *htab)
203{
204 unsigned int idx;
205 size_t key_len = strlen(match);
206
207 for (idx = last_idx + 1; idx < htab->size; ++idx) {
Kim Phillipsaf4d9072011-04-04 15:17:45 +0000208 if (htab->table[idx].used <= 0)
Mike Frysinger560d4242010-12-17 16:51:59 -0500209 continue;
210 if (!strncmp(match, htab->table[idx].entry.key, key_len)) {
211 *retval = &htab->table[idx].entry;
212 return idx;
213 }
214 }
215
216 __set_errno(ESRCH);
217 *retval = NULL;
218 return 0;
219}
220
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600221/*
222 * Compare an existing entry with the desired key, and overwrite if the action
223 * is ENTER. This is simply a helper function for hsearch_r().
224 */
225static inline int _compare_and_overwrite_entry(ENTRY item, ACTION action,
226 ENTRY **retval, struct hsearch_data *htab, int flag,
227 unsigned int hval, unsigned int idx)
228{
229 if (htab->table[idx].used == hval
230 && strcmp(item.key, htab->table[idx].entry.key) == 0) {
231 /* Overwrite existing value? */
232 if ((action == ENTER) && (item.data != NULL)) {
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600233 /* check for permission */
234 if (htab->change_ok != NULL && htab->change_ok(
235 &htab->table[idx].entry, item.data,
236 env_op_overwrite, flag)) {
237 debug("change_ok() rejected setting variable "
238 "%s, skipping it!\n", item.key);
239 __set_errno(EPERM);
240 *retval = NULL;
241 return 0;
242 }
243
Joe Hershberger170ab112012-12-11 22:16:24 -0600244 /* If there is a callback, call it */
245 if (htab->table[idx].entry.callback &&
246 htab->table[idx].entry.callback(item.key,
247 item.data, env_op_overwrite, flag)) {
248 debug("callback() rejected setting variable "
249 "%s, skipping it!\n", item.key);
250 __set_errno(EINVAL);
251 *retval = NULL;
252 return 0;
253 }
254
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600255 free(htab->table[idx].entry.data);
256 htab->table[idx].entry.data = strdup(item.data);
257 if (!htab->table[idx].entry.data) {
258 __set_errno(ENOMEM);
259 *retval = NULL;
260 return 0;
261 }
262 }
263 /* return found entry */
264 *retval = &htab->table[idx].entry;
265 return idx;
266 }
267 /* keep searching */
268 return -1;
269}
270
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200271int hsearch_r(ENTRY item, ACTION action, ENTRY ** retval,
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600272 struct hsearch_data *htab, int flag)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200273{
274 unsigned int hval;
275 unsigned int count;
276 unsigned int len = strlen(item.key);
277 unsigned int idx;
Peter Baradac81c1222011-03-21 19:05:20 -0400278 unsigned int first_deleted = 0;
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600279 int ret;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200280
281 /* Compute an value for the given string. Perhaps use a better method. */
282 hval = len;
283 count = len;
284 while (count-- > 0) {
285 hval <<= 4;
286 hval += item.key[count];
287 }
288
289 /*
290 * First hash function:
291 * simply take the modul but prevent zero.
292 */
293 hval %= htab->size;
294 if (hval == 0)
295 ++hval;
296
297 /* The first index tried. */
298 idx = hval;
299
300 if (htab->table[idx].used) {
301 /*
Wolfgang Denk071bc922010-10-27 22:48:30 +0200302 * Further action might be required according to the
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200303 * action value.
304 */
305 unsigned hval2;
306
Peter Baradac81c1222011-03-21 19:05:20 -0400307 if (htab->table[idx].used == -1
308 && !first_deleted)
309 first_deleted = idx;
310
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600311 ret = _compare_and_overwrite_entry(item, action, retval, htab,
312 flag, hval, idx);
313 if (ret != -1)
314 return ret;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200315
316 /*
317 * Second hash function:
318 * as suggested in [Knuth]
319 */
320 hval2 = 1 + hval % (htab->size - 2);
321
322 do {
323 /*
Wolfgang Denk071bc922010-10-27 22:48:30 +0200324 * Because SIZE is prime this guarantees to
325 * step through all available indices.
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200326 */
327 if (idx <= hval2)
328 idx = htab->size + idx - hval2;
329 else
330 idx -= hval2;
331
332 /*
333 * If we visited all entries leave the loop
334 * unsuccessfully.
335 */
336 if (idx == hval)
337 break;
338
339 /* If entry is found use it. */
Joe Hershberger3d3b52f2012-12-11 22:16:20 -0600340 ret = _compare_and_overwrite_entry(item, action, retval,
341 htab, flag, hval, idx);
342 if (ret != -1)
343 return ret;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200344 }
345 while (htab->table[idx].used);
346 }
347
348 /* An empty bucket has been found. */
349 if (action == ENTER) {
350 /*
Wolfgang Denk071bc922010-10-27 22:48:30 +0200351 * If table is full and another entry should be
352 * entered return with error.
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200353 */
354 if (htab->filled == htab->size) {
355 __set_errno(ENOMEM);
356 *retval = NULL;
357 return 0;
358 }
359
360 /*
361 * Create new entry;
362 * create copies of item.key and item.data
363 */
Peter Baradac81c1222011-03-21 19:05:20 -0400364 if (first_deleted)
365 idx = first_deleted;
366
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200367 htab->table[idx].used = hval;
368 htab->table[idx].entry.key = strdup(item.key);
369 htab->table[idx].entry.data = strdup(item.data);
370 if (!htab->table[idx].entry.key ||
371 !htab->table[idx].entry.data) {
372 __set_errno(ENOMEM);
373 *retval = NULL;
374 return 0;
375 }
376
377 ++htab->filled;
378
Joe Hershberger170ab112012-12-11 22:16:24 -0600379 /* This is a new entry, so look up a possible callback */
380 env_callback_init(&htab->table[idx].entry);
Joe Hershberger25980902012-12-11 22:16:31 -0600381 /* Also look for flags */
382 env_flags_init(&htab->table[idx].entry);
Joe Hershberger170ab112012-12-11 22:16:24 -0600383
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600384 /* check for permission */
385 if (htab->change_ok != NULL && htab->change_ok(
386 &htab->table[idx].entry, item.data, env_op_create, flag)) {
387 debug("change_ok() rejected setting variable "
388 "%s, skipping it!\n", item.key);
389 _hdelete(item.key, htab, &htab->table[idx].entry, idx);
390 __set_errno(EPERM);
391 *retval = NULL;
392 return 0;
393 }
394
Joe Hershberger170ab112012-12-11 22:16:24 -0600395 /* If there is a callback, call it */
396 if (htab->table[idx].entry.callback &&
397 htab->table[idx].entry.callback(item.key, item.data,
398 env_op_create, flag)) {
399 debug("callback() rejected setting variable "
400 "%s, skipping it!\n", item.key);
401 _hdelete(item.key, htab, &htab->table[idx].entry, idx);
402 __set_errno(EINVAL);
403 *retval = NULL;
404 return 0;
405 }
406
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200407 /* return new entry */
408 *retval = &htab->table[idx].entry;
409 return 1;
410 }
411
412 __set_errno(ESRCH);
413 *retval = NULL;
414 return 0;
415}
416
417
418/*
419 * hdelete()
420 */
421
422/*
423 * The standard implementation of hsearch(3) does not provide any way
424 * to delete any entries from the hash table. We extend the code to
425 * do that.
426 */
427
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600428static void _hdelete(const char *key, struct hsearch_data *htab, ENTRY *ep,
429 int idx)
430{
431 /* free used ENTRY */
432 debug("hdelete: DELETING key \"%s\"\n", key);
433 free((void *)ep->key);
434 free(ep->data);
Joe Hershberger170ab112012-12-11 22:16:24 -0600435 ep->callback = NULL;
Joe Hershberger25980902012-12-11 22:16:31 -0600436 ep->flags = 0;
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600437 htab->table[idx].used = -1;
438
439 --htab->filled;
440}
441
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600442int hdelete_r(const char *key, struct hsearch_data *htab, int flag)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200443{
444 ENTRY e, *ep;
445 int idx;
446
447 debug("hdelete: DELETE key \"%s\"\n", key);
448
449 e.key = (char *)key;
450
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600451 idx = hsearch_r(e, FIND, &ep, htab, 0);
452 if (idx == 0) {
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200453 __set_errno(ESRCH);
454 return 0; /* not found */
455 }
456
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600457 /* Check for permission */
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600458 if (htab->change_ok != NULL &&
459 htab->change_ok(ep, NULL, env_op_delete, flag)) {
460 debug("change_ok() rejected deleting variable "
461 "%s, skipping it!\n", key);
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600462 __set_errno(EPERM);
463 return 0;
464 }
465
Joe Hershberger170ab112012-12-11 22:16:24 -0600466 /* If there is a callback, call it */
467 if (htab->table[idx].entry.callback &&
468 htab->table[idx].entry.callback(key, NULL, env_op_delete, flag)) {
469 debug("callback() rejected deleting variable "
470 "%s, skipping it!\n", key);
471 __set_errno(EINVAL);
472 return 0;
473 }
474
Joe Hershberger7afcf3a2012-12-11 22:16:21 -0600475 _hdelete(key, htab, ep, idx);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200476
477 return 1;
478}
479
480/*
481 * hexport()
482 */
483
Ilya Yanok7ac2fe22012-09-18 00:22:50 +0000484#ifndef CONFIG_SPL_BUILD
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200485/*
486 * Export the data stored in the hash table in linearized form.
487 *
488 * Entries are exported as "name=value" strings, separated by an
489 * arbitrary (non-NUL, of course) separator character. This allows to
490 * use this function both when formatting the U-Boot environment for
491 * external storage (using '\0' as separator), but also when using it
492 * for the "printenv" command to print all variables, simply by using
493 * as '\n" as separator. This can also be used for new features like
494 * exporting the environment data as text file, including the option
495 * for later re-import.
496 *
497 * The entries in the result list will be sorted by ascending key
498 * values.
499 *
500 * If the separator character is different from NUL, then any
501 * separator characters and backslash characters in the values will
502 * be escaped by a preceeding backslash in output. This is needed for
503 * example to enable multi-line values, especially when the output
504 * shall later be parsed (for example, for re-import).
505 *
506 * There are several options how the result buffer is handled:
507 *
508 * *resp size
509 * -----------
510 * NULL 0 A string of sufficient length will be allocated.
511 * NULL >0 A string of the size given will be
512 * allocated. An error will be returned if the size is
513 * not sufficient. Any unused bytes in the string will
514 * be '\0'-padded.
515 * !NULL 0 The user-supplied buffer will be used. No length
516 * checking will be performed, i. e. it is assumed that
517 * the buffer size will always be big enough. DANGEROUS.
518 * !NULL >0 The user-supplied buffer will be used. An error will
519 * be returned if the size is not sufficient. Any unused
520 * bytes in the string will be '\0'-padded.
521 */
522
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200523static int cmpkey(const void *p1, const void *p2)
524{
525 ENTRY *e1 = *(ENTRY **) p1;
526 ENTRY *e2 = *(ENTRY **) p2;
527
528 return (strcmp(e1->key, e2->key));
529}
530
Wolfgang Denkbe29df62013-03-23 23:50:32 +0000531static int match_string(int flag, const char *str, const char *pat, void *priv)
Wolfgang Denk5a31ea02013-03-23 23:50:29 +0000532{
533 switch (flag & H_MATCH_METHOD) {
534 case H_MATCH_IDENT:
535 if (strcmp(str, pat) == 0)
536 return 1;
537 break;
538 case H_MATCH_SUBSTR:
539 if (strstr(str, pat))
540 return 1;
541 break;
Wolfgang Denkbe29df62013-03-23 23:50:32 +0000542#ifdef CONFIG_REGEX
543 case H_MATCH_REGEX:
544 {
545 struct slre *slrep = (struct slre *)priv;
546 struct cap caps[slrep->num_caps + 2];
547
548 if (slre_match(slrep, str, strlen(str), caps))
549 return 1;
550 }
551 break;
552#endif
Wolfgang Denk5a31ea02013-03-23 23:50:29 +0000553 default:
554 printf("## ERROR: unsupported match method: 0x%02x\n",
555 flag & H_MATCH_METHOD);
556 break;
557 }
558 return 0;
559}
560
561static int match_entry(ENTRY *ep, int flag,
Wolfgang Denkea009d42013-03-23 23:50:28 +0000562 int argc, char * const argv[])
563{
564 int arg;
Wolfgang Denkbe29df62013-03-23 23:50:32 +0000565 void *priv = NULL;
Wolfgang Denkea009d42013-03-23 23:50:28 +0000566
Wolfgang Denk5a31ea02013-03-23 23:50:29 +0000567 for (arg = 1; arg < argc; ++arg) {
Wolfgang Denkbe29df62013-03-23 23:50:32 +0000568#ifdef CONFIG_REGEX
569 struct slre slre;
570
571 if (slre_compile(&slre, argv[arg]) == 0) {
572 printf("Error compiling regex: %s\n", slre.err_str);
573 return 0;
574 }
575
576 priv = (void *)&slre;
577#endif
Wolfgang Denkea009d42013-03-23 23:50:28 +0000578 if (flag & H_MATCH_KEY) {
Wolfgang Denkbe29df62013-03-23 23:50:32 +0000579 if (match_string(flag, ep->key, argv[arg], priv))
Wolfgang Denk5a31ea02013-03-23 23:50:29 +0000580 return 1;
581 }
582 if (flag & H_MATCH_DATA) {
Wolfgang Denkbe29df62013-03-23 23:50:32 +0000583 if (match_string(flag, ep->data, argv[arg], priv))
Wolfgang Denk5a31ea02013-03-23 23:50:29 +0000584 return 1;
Wolfgang Denkea009d42013-03-23 23:50:28 +0000585 }
586 }
587 return 0;
588}
589
Joe Hershbergerbe112352012-12-11 22:16:23 -0600590ssize_t hexport_r(struct hsearch_data *htab, const char sep, int flag,
Wolfgang Denk37f2fe72011-11-06 22:49:44 +0100591 char **resp, size_t size,
592 int argc, char * const argv[])
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200593{
594 ENTRY *list[htab->size];
595 char *res, *p;
596 size_t totlen;
597 int i, n;
598
599 /* Test for correct arguments. */
600 if ((resp == NULL) || (htab == NULL)) {
601 __set_errno(EINVAL);
602 return (-1);
603 }
604
Simon Glassff856282011-11-21 19:04:23 +0000605 debug("EXPORT table = %p, htab.size = %d, htab.filled = %d, "
606 "size = %zu\n", htab, htab->size, htab->filled, size);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200607 /*
608 * Pass 1:
609 * search used entries,
610 * save addresses and compute total length
611 */
612 for (i = 1, n = 0, totlen = 0; i <= htab->size; ++i) {
613
Peter Baradac81c1222011-03-21 19:05:20 -0400614 if (htab->table[i].used > 0) {
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200615 ENTRY *ep = &htab->table[i].entry;
Wolfgang Denk5a31ea02013-03-23 23:50:29 +0000616 int found = match_entry(ep, flag, argc, argv);
Wolfgang Denk37f2fe72011-11-06 22:49:44 +0100617
Wolfgang Denk37f2fe72011-11-06 22:49:44 +0100618 if ((argc > 0) && (found == 0))
619 continue;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200620
Joe Hershbergerbe112352012-12-11 22:16:23 -0600621 if ((flag & H_HIDE_DOT) && ep->key[0] == '.')
622 continue;
623
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200624 list[n++] = ep;
625
626 totlen += strlen(ep->key) + 2;
627
628 if (sep == '\0') {
629 totlen += strlen(ep->data);
630 } else { /* check if escapes are needed */
631 char *s = ep->data;
632
633 while (*s) {
634 ++totlen;
635 /* add room for needed escape chars */
636 if ((*s == sep) || (*s == '\\'))
637 ++totlen;
638 ++s;
639 }
640 }
641 totlen += 2; /* for '=' and 'sep' char */
642 }
643 }
644
645#ifdef DEBUG
646 /* Pass 1a: print unsorted list */
647 printf("Unsorted: n=%d\n", n);
648 for (i = 0; i < n; ++i) {
649 printf("\t%3d: %p ==> %-10s => %s\n",
650 i, list[i], list[i]->key, list[i]->data);
651 }
652#endif
653
654 /* Sort list by keys */
655 qsort(list, n, sizeof(ENTRY *), cmpkey);
656
657 /* Check if the user supplied buffer size is sufficient */
658 if (size) {
659 if (size < totlen + 1) { /* provided buffer too small */
Simon Glassff856282011-11-21 19:04:23 +0000660 printf("Env export buffer too small: %zu, "
661 "but need %zu\n", size, totlen + 1);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200662 __set_errno(ENOMEM);
663 return (-1);
664 }
665 } else {
666 size = totlen + 1;
667 }
668
669 /* Check if the user provided a buffer */
670 if (*resp) {
671 /* yes; clear it */
672 res = *resp;
673 memset(res, '\0', size);
674 } else {
675 /* no, allocate and clear one */
676 *resp = res = calloc(1, size);
677 if (res == NULL) {
678 __set_errno(ENOMEM);
679 return (-1);
680 }
681 }
682 /*
683 * Pass 2:
684 * export sorted list of result data
685 */
686 for (i = 0, p = res; i < n; ++i) {
Wolfgang Denk84b5e802011-07-29 14:42:18 +0200687 const char *s;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200688
689 s = list[i]->key;
690 while (*s)
691 *p++ = *s++;
692 *p++ = '=';
693
694 s = list[i]->data;
695
696 while (*s) {
697 if ((*s == sep) || (*s == '\\'))
698 *p++ = '\\'; /* escape */
699 *p++ = *s++;
700 }
701 *p++ = sep;
702 }
703 *p = '\0'; /* terminate result */
704
705 return size;
706}
Ilya Yanok7ac2fe22012-09-18 00:22:50 +0000707#endif
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200708
709
710/*
711 * himport()
712 */
713
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000714/*
715 * Check whether variable 'name' is amongst vars[],
716 * and remove all instances by setting the pointer to NULL
717 */
718static int drop_var_from_set(const char *name, int nvars, char * vars[])
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000719{
720 int i = 0;
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000721 int res = 0;
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000722
723 /* No variables specified means process all of them */
724 if (nvars == 0)
725 return 1;
726
727 for (i = 0; i < nvars; i++) {
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000728 if (vars[i] == NULL)
729 continue;
730 /* If we found it, delete all of them */
731 if (!strcmp(name, vars[i])) {
732 vars[i] = NULL;
733 res = 1;
734 }
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000735 }
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000736 if (!res)
737 debug("Skipping non-listed variable %s\n", name);
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000738
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000739 return res;
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000740}
741
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200742/*
743 * Import linearized data into hash table.
744 *
745 * This is the inverse function to hexport(): it takes a linear list
746 * of "name=value" pairs and creates hash table entries from it.
747 *
748 * Entries without "value", i. e. consisting of only "name" or
749 * "name=", will cause this entry to be deleted from the hash table.
750 *
751 * The "flag" argument can be used to control the behaviour: when the
752 * H_NOCLEAR bit is set, then an existing hash table will kept, i. e.
753 * new data will be added to an existing hash table; otherwise, old
754 * data will be discarded and a new hash table will be created.
755 *
756 * The separator character for the "name=value" pairs can be selected,
757 * so we both support importing from externally stored environment
758 * data (separated by NUL characters) and from plain text files
759 * (entries separated by newline characters).
760 *
761 * To allow for nicely formatted text input, leading white space
762 * (sequences of SPACE and TAB chars) is ignored, and entries starting
763 * (after removal of any leading white space) with a '#' character are
764 * considered comments and ignored.
765 *
766 * [NOTE: this means that a variable name cannot start with a '#'
767 * character.]
768 *
769 * When using a non-NUL separator character, backslash is used as
770 * escape character in the value part, allowing for example for
771 * multi-line values.
772 *
773 * In theory, arbitrary separator characters can be used, but only
774 * '\0' and '\n' have really been tested.
775 */
776
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200777int himport_r(struct hsearch_data *htab,
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000778 const char *env, size_t size, const char sep, int flag,
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600779 int nvars, char * const vars[])
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200780{
781 char *data, *sp, *dp, *name, *value;
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000782 char *localvars[nvars];
783 int i;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200784
785 /* Test for correct arguments. */
786 if (htab == NULL) {
787 __set_errno(EINVAL);
788 return 0;
789 }
790
791 /* we allocate new space to make sure we can write to the array */
792 if ((data = malloc(size)) == NULL) {
Simon Glassff856282011-11-21 19:04:23 +0000793 debug("himport_r: can't malloc %zu bytes\n", size);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200794 __set_errno(ENOMEM);
795 return 0;
796 }
797 memcpy(data, env, size);
798 dp = data;
799
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000800 /* make a local copy of the list of variables */
801 if (nvars)
802 memcpy(localvars, vars, sizeof(vars[0]) * nvars);
803
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200804 if ((flag & H_NOCLEAR) == 0) {
805 /* Destroy old hash table if one exists */
806 debug("Destroy Hash Table: %p table = %p\n", htab,
807 htab->table);
808 if (htab->table)
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600809 hdestroy_r(htab);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200810 }
811
812 /*
813 * Create new hash table (if needed). The computation of the hash
814 * table size is based on heuristics: in a sample of some 70+
815 * existing systems we found an average size of 39+ bytes per entry
816 * in the environment (for the whole key=value pair). Assuming a
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200817 * size of 8 per entry (= safety factor of ~5) should provide enough
818 * safety margin for any existing environment definitions and still
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200819 * allow for more than enough dynamic additions. Note that the
820 * "size" argument is supposed to give the maximum enviroment size
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200821 * (CONFIG_ENV_SIZE). This heuristics will result in
822 * unreasonably large numbers (and thus memory footprint) for
823 * big flash environments (>8,000 entries for 64 KB
Andreas Bießmannfc5fc762010-10-01 22:51:02 +0200824 * envrionment size), so we clip it to a reasonable value.
825 * On the other hand we need to add some more entries for free
826 * space when importing very small buffers. Both boundaries can
827 * be overwritten in the board config file if needed.
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200828 */
829
830 if (!htab->table) {
Andreas Bießmannfc5fc762010-10-01 22:51:02 +0200831 int nent = CONFIG_ENV_MIN_ENTRIES + size / 8;
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200832
833 if (nent > CONFIG_ENV_MAX_ENTRIES)
834 nent = CONFIG_ENV_MAX_ENTRIES;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200835
836 debug("Create Hash Table: N=%d\n", nent);
837
838 if (hcreate_r(nent, htab) == 0) {
839 free(data);
840 return 0;
841 }
842 }
843
844 /* Parse environment; allow for '\0' and 'sep' as separators */
845 do {
846 ENTRY e, *rv;
847
848 /* skip leading white space */
Jason Hobbs4d91a6e2011-08-23 11:06:54 +0000849 while (isblank(*dp))
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200850 ++dp;
851
852 /* skip comment lines */
853 if (*dp == '#') {
854 while (*dp && (*dp != sep))
855 ++dp;
856 ++dp;
857 continue;
858 }
859
860 /* parse name */
861 for (name = dp; *dp != '=' && *dp && *dp != sep; ++dp)
862 ;
863
864 /* deal with "name" and "name=" entries (delete var) */
865 if (*dp == '\0' || *(dp + 1) == '\0' ||
866 *dp == sep || *(dp + 1) == sep) {
867 if (*dp == '=')
868 *dp++ = '\0';
869 *dp++ = '\0'; /* terminate name */
870
871 debug("DELETE CANDIDATE: \"%s\"\n", name);
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000872 if (!drop_var_from_set(name, nvars, localvars))
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000873 continue;
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200874
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600875 if (hdelete_r(name, htab, flag) == 0)
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200876 debug("DELETE ERROR ##############################\n");
877
878 continue;
879 }
880 *dp++ = '\0'; /* terminate name */
881
882 /* parse value; deal with escapes */
883 for (value = sp = dp; *dp && (*dp != sep); ++dp) {
884 if ((*dp == '\\') && *(dp + 1))
885 ++dp;
886 *sp++ = *dp;
887 }
888 *sp++ = '\0'; /* terminate value */
889 ++dp;
890
Lucian Cojocare4fdcad2013-04-28 11:31:57 +0000891 if (*name == 0) {
892 debug("INSERT: unable to use an empty key\n");
893 __set_errno(EINVAL);
894 return 0;
895 }
896
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000897 /* Skip variables which are not supposed to be processed */
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000898 if (!drop_var_from_set(name, nvars, localvars))
Gerlando Falauto348b1f12012-08-24 00:11:38 +0000899 continue;
900
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200901 /* enter into hash table */
902 e.key = name;
903 e.data = value;
904
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600905 hsearch_r(e, ENTER, &rv, htab, flag);
Joe Hershberger170ab112012-12-11 22:16:24 -0600906 if (rv == NULL)
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200907 printf("himport_r: can't insert \"%s=%s\" into hash table\n",
908 name, value);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200909
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200910 debug("INSERT: table %p, filled %d/%d rv %p ==> name=\"%s\" value=\"%s\"\n",
911 htab, htab->filled, htab->size,
912 rv, name, value);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200913 } while ((dp < data + size) && *dp); /* size check needed for text */
914 /* without '\0' termination */
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200915 debug("INSERT: free(data = %p)\n", data);
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200916 free(data);
917
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000918 /* process variables which were not considered */
919 for (i = 0; i < nvars; i++) {
920 if (localvars[i] == NULL)
921 continue;
922 /*
923 * All variables which were not deleted from the variable list
924 * were not present in the imported env
925 * This could mean two things:
926 * a) if the variable was present in current env, we delete it
927 * b) if the variable was not present in current env, we notify
928 * it might be a typo
929 */
Joe Hershbergerc4e00572012-12-11 22:16:19 -0600930 if (hdelete_r(localvars[i], htab, flag) == 0)
Gerlando Falautod5370fe2012-08-26 21:53:00 +0000931 printf("WARNING: '%s' neither in running nor in imported env!\n", localvars[i]);
932 else
933 printf("WARNING: '%s' not in imported env, deleting it!\n", localvars[i]);
934 }
935
Wolfgang Denkea882ba2010-06-20 23:33:59 +0200936 debug("INSERT: done\n");
Wolfgang Denka6826fb2010-06-20 13:17:12 +0200937 return 1; /* everything OK */
938}
Joe Hershberger170ab112012-12-11 22:16:24 -0600939
940/*
941 * hwalk_r()
942 */
943
944/*
945 * Walk all of the entries in the hash, calling the callback for each one.
946 * this allows some generic operation to be performed on each element.
947 */
948int hwalk_r(struct hsearch_data *htab, int (*callback)(ENTRY *))
949{
950 int i;
951 int retval;
952
953 for (i = 1; i <= htab->size; ++i) {
954 if (htab->table[i].used > 0) {
955 retval = callback(&htab->table[i].entry);
956 if (retval)
957 return retval;
958 }
959 }
960
961 return 0;
962}