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![Pierre Aubert](/assets/img/avatar_default.png)
The env export command doesn't export the first variable of the list
since commit 5a31ea04c9
"env grep" - reimplement command using hexport_r()
Signed-off-by: Pierre Aubert <p.aubert@staubli.com>
963 lines
24 KiB
C
963 lines
24 KiB
C
/*
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* This implementation is based on code from uClibc-0.9.30.3 but was
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* modified and extended for use within U-Boot.
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*
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* Copyright (C) 2010-2013 Wolfgang Denk <wd@denx.de>
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*
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* Original license header:
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*
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* Copyright (C) 1993, 1995, 1996, 1997, 2002 Free Software Foundation, Inc.
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* This file is part of the GNU C Library.
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* Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1993.
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*
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* SPDX-License-Identifier: LGPL-2.1+
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*/
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#include <errno.h>
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#include <malloc.h>
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#ifdef USE_HOSTCC /* HOST build */
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# include <string.h>
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# include <assert.h>
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# include <ctype.h>
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# ifndef debug
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# ifdef DEBUG
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# define debug(fmt,args...) printf(fmt ,##args)
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# else
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# define debug(fmt,args...)
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# endif
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# endif
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#else /* U-Boot build */
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# include <common.h>
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# include <linux/string.h>
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# include <linux/ctype.h>
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#endif
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#ifndef CONFIG_ENV_MIN_ENTRIES /* minimum number of entries */
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#define CONFIG_ENV_MIN_ENTRIES 64
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#endif
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#ifndef CONFIG_ENV_MAX_ENTRIES /* maximum number of entries */
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#define CONFIG_ENV_MAX_ENTRIES 512
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#endif
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#include <env_callback.h>
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#include <env_flags.h>
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#include <search.h>
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#include <slre.h>
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/*
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* [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986
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* [Knuth] The Art of Computer Programming, part 3 (6.4)
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*/
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/*
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* The reentrant version has no static variables to maintain the state.
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* Instead the interface of all functions is extended to take an argument
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* which describes the current status.
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*/
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typedef struct _ENTRY {
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int used;
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ENTRY entry;
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} _ENTRY;
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static void _hdelete(const char *key, struct hsearch_data *htab, ENTRY *ep,
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int idx);
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/*
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* hcreate()
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*/
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/*
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* For the used double hash method the table size has to be a prime. To
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* correct the user given table size we need a prime test. This trivial
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* algorithm is adequate because
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* a) the code is (most probably) called a few times per program run and
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* b) the number is small because the table must fit in the core
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* */
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static int isprime(unsigned int number)
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{
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/* no even number will be passed */
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unsigned int div = 3;
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while (div * div < number && number % div != 0)
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div += 2;
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return number % div != 0;
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}
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/*
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* Before using the hash table we must allocate memory for it.
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* Test for an existing table are done. We allocate one element
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* more as the found prime number says. This is done for more effective
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* indexing as explained in the comment for the hsearch function.
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* The contents of the table is zeroed, especially the field used
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* becomes zero.
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*/
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int hcreate_r(size_t nel, struct hsearch_data *htab)
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{
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/* Test for correct arguments. */
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if (htab == NULL) {
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__set_errno(EINVAL);
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return 0;
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}
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/* There is still another table active. Return with error. */
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if (htab->table != NULL)
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return 0;
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/* Change nel to the first prime number not smaller as nel. */
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nel |= 1; /* make odd */
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while (!isprime(nel))
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nel += 2;
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htab->size = nel;
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htab->filled = 0;
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/* allocate memory and zero out */
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htab->table = (_ENTRY *) calloc(htab->size + 1, sizeof(_ENTRY));
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if (htab->table == NULL)
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return 0;
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/* everything went alright */
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return 1;
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}
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/*
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* hdestroy()
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*/
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/*
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* After using the hash table it has to be destroyed. The used memory can
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* be freed and the local static variable can be marked as not used.
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*/
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void hdestroy_r(struct hsearch_data *htab)
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{
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int i;
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/* Test for correct arguments. */
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if (htab == NULL) {
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__set_errno(EINVAL);
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return;
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}
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/* free used memory */
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for (i = 1; i <= htab->size; ++i) {
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if (htab->table[i].used > 0) {
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ENTRY *ep = &htab->table[i].entry;
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free((void *)ep->key);
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free(ep->data);
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}
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}
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free(htab->table);
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/* the sign for an existing table is an value != NULL in htable */
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htab->table = NULL;
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}
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/*
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* hsearch()
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*/
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/*
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* This is the search function. It uses double hashing with open addressing.
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* The argument item.key has to be a pointer to an zero terminated, most
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* probably strings of chars. The function for generating a number of the
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* strings is simple but fast. It can be replaced by a more complex function
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* like ajw (see [Aho,Sethi,Ullman]) if the needs are shown.
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*
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* We use an trick to speed up the lookup. The table is created by hcreate
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* with one more element available. This enables us to use the index zero
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* special. This index will never be used because we store the first hash
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* index in the field used where zero means not used. Every other value
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* means used. The used field can be used as a first fast comparison for
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* equality of the stored and the parameter value. This helps to prevent
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* unnecessary expensive calls of strcmp.
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*
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* This implementation differs from the standard library version of
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* this function in a number of ways:
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*
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* - While the standard version does not make any assumptions about
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* the type of the stored data objects at all, this implementation
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* works with NUL terminated strings only.
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* - Instead of storing just pointers to the original objects, we
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* create local copies so the caller does not need to care about the
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* data any more.
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* - The standard implementation does not provide a way to update an
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* existing entry. This version will create a new entry or update an
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* existing one when both "action == ENTER" and "item.data != NULL".
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* - Instead of returning 1 on success, we return the index into the
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* internal hash table, which is also guaranteed to be positive.
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* This allows us direct access to the found hash table slot for
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* example for functions like hdelete().
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*/
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int hmatch_r(const char *match, int last_idx, ENTRY ** retval,
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struct hsearch_data *htab)
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{
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unsigned int idx;
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size_t key_len = strlen(match);
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for (idx = last_idx + 1; idx < htab->size; ++idx) {
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if (htab->table[idx].used <= 0)
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continue;
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if (!strncmp(match, htab->table[idx].entry.key, key_len)) {
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*retval = &htab->table[idx].entry;
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return idx;
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}
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}
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__set_errno(ESRCH);
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*retval = NULL;
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return 0;
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}
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/*
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* Compare an existing entry with the desired key, and overwrite if the action
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* is ENTER. This is simply a helper function for hsearch_r().
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*/
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static inline int _compare_and_overwrite_entry(ENTRY item, ACTION action,
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ENTRY **retval, struct hsearch_data *htab, int flag,
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unsigned int hval, unsigned int idx)
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{
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if (htab->table[idx].used == hval
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&& strcmp(item.key, htab->table[idx].entry.key) == 0) {
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/* Overwrite existing value? */
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if ((action == ENTER) && (item.data != NULL)) {
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/* check for permission */
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if (htab->change_ok != NULL && htab->change_ok(
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&htab->table[idx].entry, item.data,
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env_op_overwrite, flag)) {
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debug("change_ok() rejected setting variable "
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"%s, skipping it!\n", item.key);
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__set_errno(EPERM);
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*retval = NULL;
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return 0;
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}
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/* If there is a callback, call it */
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if (htab->table[idx].entry.callback &&
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htab->table[idx].entry.callback(item.key,
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item.data, env_op_overwrite, flag)) {
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debug("callback() rejected setting variable "
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"%s, skipping it!\n", item.key);
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__set_errno(EINVAL);
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*retval = NULL;
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return 0;
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}
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free(htab->table[idx].entry.data);
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htab->table[idx].entry.data = strdup(item.data);
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if (!htab->table[idx].entry.data) {
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__set_errno(ENOMEM);
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*retval = NULL;
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return 0;
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}
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}
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/* return found entry */
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*retval = &htab->table[idx].entry;
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return idx;
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}
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/* keep searching */
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return -1;
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}
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int hsearch_r(ENTRY item, ACTION action, ENTRY ** retval,
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struct hsearch_data *htab, int flag)
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{
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unsigned int hval;
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unsigned int count;
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unsigned int len = strlen(item.key);
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unsigned int idx;
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unsigned int first_deleted = 0;
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int ret;
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/* Compute an value for the given string. Perhaps use a better method. */
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hval = len;
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count = len;
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while (count-- > 0) {
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hval <<= 4;
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hval += item.key[count];
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}
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/*
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* First hash function:
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* simply take the modul but prevent zero.
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*/
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hval %= htab->size;
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if (hval == 0)
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++hval;
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/* The first index tried. */
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idx = hval;
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if (htab->table[idx].used) {
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/*
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* Further action might be required according to the
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* action value.
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*/
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unsigned hval2;
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if (htab->table[idx].used == -1
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&& !first_deleted)
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first_deleted = idx;
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ret = _compare_and_overwrite_entry(item, action, retval, htab,
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flag, hval, idx);
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if (ret != -1)
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return ret;
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/*
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* Second hash function:
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* as suggested in [Knuth]
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*/
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hval2 = 1 + hval % (htab->size - 2);
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do {
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/*
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* Because SIZE is prime this guarantees to
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* step through all available indices.
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*/
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if (idx <= hval2)
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idx = htab->size + idx - hval2;
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else
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idx -= hval2;
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/*
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* If we visited all entries leave the loop
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* unsuccessfully.
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*/
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if (idx == hval)
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break;
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/* If entry is found use it. */
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ret = _compare_and_overwrite_entry(item, action, retval,
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htab, flag, hval, idx);
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if (ret != -1)
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return ret;
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}
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while (htab->table[idx].used);
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}
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/* An empty bucket has been found. */
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if (action == ENTER) {
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/*
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* If table is full and another entry should be
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* entered return with error.
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*/
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if (htab->filled == htab->size) {
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__set_errno(ENOMEM);
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*retval = NULL;
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return 0;
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}
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/*
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* Create new entry;
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* create copies of item.key and item.data
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*/
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if (first_deleted)
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idx = first_deleted;
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htab->table[idx].used = hval;
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htab->table[idx].entry.key = strdup(item.key);
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htab->table[idx].entry.data = strdup(item.data);
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if (!htab->table[idx].entry.key ||
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!htab->table[idx].entry.data) {
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__set_errno(ENOMEM);
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*retval = NULL;
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return 0;
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}
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++htab->filled;
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/* This is a new entry, so look up a possible callback */
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env_callback_init(&htab->table[idx].entry);
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/* Also look for flags */
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env_flags_init(&htab->table[idx].entry);
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/* check for permission */
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if (htab->change_ok != NULL && htab->change_ok(
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&htab->table[idx].entry, item.data, env_op_create, flag)) {
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debug("change_ok() rejected setting variable "
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"%s, skipping it!\n", item.key);
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_hdelete(item.key, htab, &htab->table[idx].entry, idx);
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__set_errno(EPERM);
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*retval = NULL;
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return 0;
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}
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/* If there is a callback, call it */
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if (htab->table[idx].entry.callback &&
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htab->table[idx].entry.callback(item.key, item.data,
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env_op_create, flag)) {
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debug("callback() rejected setting variable "
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"%s, skipping it!\n", item.key);
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_hdelete(item.key, htab, &htab->table[idx].entry, idx);
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__set_errno(EINVAL);
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*retval = NULL;
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return 0;
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}
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/* return new entry */
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*retval = &htab->table[idx].entry;
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return 1;
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}
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__set_errno(ESRCH);
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*retval = NULL;
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return 0;
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}
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/*
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* hdelete()
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*/
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/*
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* The standard implementation of hsearch(3) does not provide any way
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* to delete any entries from the hash table. We extend the code to
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* do that.
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*/
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static void _hdelete(const char *key, struct hsearch_data *htab, ENTRY *ep,
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int idx)
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{
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/* free used ENTRY */
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debug("hdelete: DELETING key \"%s\"\n", key);
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free((void *)ep->key);
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free(ep->data);
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ep->callback = NULL;
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ep->flags = 0;
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htab->table[idx].used = -1;
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--htab->filled;
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}
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int hdelete_r(const char *key, struct hsearch_data *htab, int flag)
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{
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ENTRY e, *ep;
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int idx;
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debug("hdelete: DELETE key \"%s\"\n", key);
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e.key = (char *)key;
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idx = hsearch_r(e, FIND, &ep, htab, 0);
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if (idx == 0) {
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__set_errno(ESRCH);
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return 0; /* not found */
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}
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/* Check for permission */
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if (htab->change_ok != NULL &&
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htab->change_ok(ep, NULL, env_op_delete, flag)) {
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debug("change_ok() rejected deleting variable "
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"%s, skipping it!\n", key);
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__set_errno(EPERM);
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return 0;
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}
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/* If there is a callback, call it */
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if (htab->table[idx].entry.callback &&
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htab->table[idx].entry.callback(key, NULL, env_op_delete, flag)) {
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debug("callback() rejected deleting variable "
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"%s, skipping it!\n", key);
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__set_errno(EINVAL);
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return 0;
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}
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_hdelete(key, htab, ep, idx);
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return 1;
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}
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/*
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* hexport()
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*/
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#ifndef CONFIG_SPL_BUILD
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/*
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* Export the data stored in the hash table in linearized form.
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*
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* Entries are exported as "name=value" strings, separated by an
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* arbitrary (non-NUL, of course) separator character. This allows to
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* use this function both when formatting the U-Boot environment for
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* external storage (using '\0' as separator), but also when using it
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* for the "printenv" command to print all variables, simply by using
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* as '\n" as separator. This can also be used for new features like
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* exporting the environment data as text file, including the option
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* for later re-import.
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*
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* The entries in the result list will be sorted by ascending key
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* values.
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*
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* If the separator character is different from NUL, then any
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* separator characters and backslash characters in the values will
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* be escaped by a preceeding backslash in output. This is needed for
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* example to enable multi-line values, especially when the output
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* shall later be parsed (for example, for re-import).
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*
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* There are several options how the result buffer is handled:
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*
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* *resp size
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* -----------
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* NULL 0 A string of sufficient length will be allocated.
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* NULL >0 A string of the size given will be
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* allocated. An error will be returned if the size is
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* not sufficient. Any unused bytes in the string will
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* be '\0'-padded.
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* !NULL 0 The user-supplied buffer will be used. No length
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* checking will be performed, i. e. it is assumed that
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* the buffer size will always be big enough. DANGEROUS.
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* !NULL >0 The user-supplied buffer will be used. An error will
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* be returned if the size is not sufficient. Any unused
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* bytes in the string will be '\0'-padded.
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*/
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static int cmpkey(const void *p1, const void *p2)
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{
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ENTRY *e1 = *(ENTRY **) p1;
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ENTRY *e2 = *(ENTRY **) p2;
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return (strcmp(e1->key, e2->key));
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}
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static int match_string(int flag, const char *str, const char *pat, void *priv)
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{
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switch (flag & H_MATCH_METHOD) {
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case H_MATCH_IDENT:
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if (strcmp(str, pat) == 0)
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return 1;
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break;
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case H_MATCH_SUBSTR:
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if (strstr(str, pat))
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return 1;
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break;
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#ifdef CONFIG_REGEX
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case H_MATCH_REGEX:
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|
{
|
|
struct slre *slrep = (struct slre *)priv;
|
|
struct cap caps[slrep->num_caps + 2];
|
|
|
|
if (slre_match(slrep, str, strlen(str), caps))
|
|
return 1;
|
|
}
|
|
break;
|
|
#endif
|
|
default:
|
|
printf("## ERROR: unsupported match method: 0x%02x\n",
|
|
flag & H_MATCH_METHOD);
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int match_entry(ENTRY *ep, int flag,
|
|
int argc, char * const argv[])
|
|
{
|
|
int arg;
|
|
void *priv = NULL;
|
|
|
|
for (arg = 0; arg < argc; ++arg) {
|
|
#ifdef CONFIG_REGEX
|
|
struct slre slre;
|
|
|
|
if (slre_compile(&slre, argv[arg]) == 0) {
|
|
printf("Error compiling regex: %s\n", slre.err_str);
|
|
return 0;
|
|
}
|
|
|
|
priv = (void *)&slre;
|
|
#endif
|
|
if (flag & H_MATCH_KEY) {
|
|
if (match_string(flag, ep->key, argv[arg], priv))
|
|
return 1;
|
|
}
|
|
if (flag & H_MATCH_DATA) {
|
|
if (match_string(flag, ep->data, argv[arg], priv))
|
|
return 1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
ssize_t hexport_r(struct hsearch_data *htab, const char sep, int flag,
|
|
char **resp, size_t size,
|
|
int argc, char * const argv[])
|
|
{
|
|
ENTRY *list[htab->size];
|
|
char *res, *p;
|
|
size_t totlen;
|
|
int i, n;
|
|
|
|
/* Test for correct arguments. */
|
|
if ((resp == NULL) || (htab == NULL)) {
|
|
__set_errno(EINVAL);
|
|
return (-1);
|
|
}
|
|
|
|
debug("EXPORT table = %p, htab.size = %d, htab.filled = %d, "
|
|
"size = %zu\n", htab, htab->size, htab->filled, size);
|
|
/*
|
|
* Pass 1:
|
|
* search used entries,
|
|
* save addresses and compute total length
|
|
*/
|
|
for (i = 1, n = 0, totlen = 0; i <= htab->size; ++i) {
|
|
|
|
if (htab->table[i].used > 0) {
|
|
ENTRY *ep = &htab->table[i].entry;
|
|
int found = match_entry(ep, flag, argc, argv);
|
|
|
|
if ((argc > 0) && (found == 0))
|
|
continue;
|
|
|
|
if ((flag & H_HIDE_DOT) && ep->key[0] == '.')
|
|
continue;
|
|
|
|
list[n++] = ep;
|
|
|
|
totlen += strlen(ep->key) + 2;
|
|
|
|
if (sep == '\0') {
|
|
totlen += strlen(ep->data);
|
|
} else { /* check if escapes are needed */
|
|
char *s = ep->data;
|
|
|
|
while (*s) {
|
|
++totlen;
|
|
/* add room for needed escape chars */
|
|
if ((*s == sep) || (*s == '\\'))
|
|
++totlen;
|
|
++s;
|
|
}
|
|
}
|
|
totlen += 2; /* for '=' and 'sep' char */
|
|
}
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
/* Pass 1a: print unsorted list */
|
|
printf("Unsorted: n=%d\n", n);
|
|
for (i = 0; i < n; ++i) {
|
|
printf("\t%3d: %p ==> %-10s => %s\n",
|
|
i, list[i], list[i]->key, list[i]->data);
|
|
}
|
|
#endif
|
|
|
|
/* Sort list by keys */
|
|
qsort(list, n, sizeof(ENTRY *), cmpkey);
|
|
|
|
/* Check if the user supplied buffer size is sufficient */
|
|
if (size) {
|
|
if (size < totlen + 1) { /* provided buffer too small */
|
|
printf("Env export buffer too small: %zu, "
|
|
"but need %zu\n", size, totlen + 1);
|
|
__set_errno(ENOMEM);
|
|
return (-1);
|
|
}
|
|
} else {
|
|
size = totlen + 1;
|
|
}
|
|
|
|
/* Check if the user provided a buffer */
|
|
if (*resp) {
|
|
/* yes; clear it */
|
|
res = *resp;
|
|
memset(res, '\0', size);
|
|
} else {
|
|
/* no, allocate and clear one */
|
|
*resp = res = calloc(1, size);
|
|
if (res == NULL) {
|
|
__set_errno(ENOMEM);
|
|
return (-1);
|
|
}
|
|
}
|
|
/*
|
|
* Pass 2:
|
|
* export sorted list of result data
|
|
*/
|
|
for (i = 0, p = res; i < n; ++i) {
|
|
const char *s;
|
|
|
|
s = list[i]->key;
|
|
while (*s)
|
|
*p++ = *s++;
|
|
*p++ = '=';
|
|
|
|
s = list[i]->data;
|
|
|
|
while (*s) {
|
|
if ((*s == sep) || (*s == '\\'))
|
|
*p++ = '\\'; /* escape */
|
|
*p++ = *s++;
|
|
}
|
|
*p++ = sep;
|
|
}
|
|
*p = '\0'; /* terminate result */
|
|
|
|
return size;
|
|
}
|
|
#endif
|
|
|
|
|
|
/*
|
|
* himport()
|
|
*/
|
|
|
|
/*
|
|
* Check whether variable 'name' is amongst vars[],
|
|
* and remove all instances by setting the pointer to NULL
|
|
*/
|
|
static int drop_var_from_set(const char *name, int nvars, char * vars[])
|
|
{
|
|
int i = 0;
|
|
int res = 0;
|
|
|
|
/* No variables specified means process all of them */
|
|
if (nvars == 0)
|
|
return 1;
|
|
|
|
for (i = 0; i < nvars; i++) {
|
|
if (vars[i] == NULL)
|
|
continue;
|
|
/* If we found it, delete all of them */
|
|
if (!strcmp(name, vars[i])) {
|
|
vars[i] = NULL;
|
|
res = 1;
|
|
}
|
|
}
|
|
if (!res)
|
|
debug("Skipping non-listed variable %s\n", name);
|
|
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* Import linearized data into hash table.
|
|
*
|
|
* This is the inverse function to hexport(): it takes a linear list
|
|
* of "name=value" pairs and creates hash table entries from it.
|
|
*
|
|
* Entries without "value", i. e. consisting of only "name" or
|
|
* "name=", will cause this entry to be deleted from the hash table.
|
|
*
|
|
* The "flag" argument can be used to control the behaviour: when the
|
|
* H_NOCLEAR bit is set, then an existing hash table will kept, i. e.
|
|
* new data will be added to an existing hash table; otherwise, old
|
|
* data will be discarded and a new hash table will be created.
|
|
*
|
|
* The separator character for the "name=value" pairs can be selected,
|
|
* so we both support importing from externally stored environment
|
|
* data (separated by NUL characters) and from plain text files
|
|
* (entries separated by newline characters).
|
|
*
|
|
* To allow for nicely formatted text input, leading white space
|
|
* (sequences of SPACE and TAB chars) is ignored, and entries starting
|
|
* (after removal of any leading white space) with a '#' character are
|
|
* considered comments and ignored.
|
|
*
|
|
* [NOTE: this means that a variable name cannot start with a '#'
|
|
* character.]
|
|
*
|
|
* When using a non-NUL separator character, backslash is used as
|
|
* escape character in the value part, allowing for example for
|
|
* multi-line values.
|
|
*
|
|
* In theory, arbitrary separator characters can be used, but only
|
|
* '\0' and '\n' have really been tested.
|
|
*/
|
|
|
|
int himport_r(struct hsearch_data *htab,
|
|
const char *env, size_t size, const char sep, int flag,
|
|
int nvars, char * const vars[])
|
|
{
|
|
char *data, *sp, *dp, *name, *value;
|
|
char *localvars[nvars];
|
|
int i;
|
|
|
|
/* Test for correct arguments. */
|
|
if (htab == NULL) {
|
|
__set_errno(EINVAL);
|
|
return 0;
|
|
}
|
|
|
|
/* we allocate new space to make sure we can write to the array */
|
|
if ((data = malloc(size)) == NULL) {
|
|
debug("himport_r: can't malloc %zu bytes\n", size);
|
|
__set_errno(ENOMEM);
|
|
return 0;
|
|
}
|
|
memcpy(data, env, size);
|
|
dp = data;
|
|
|
|
/* make a local copy of the list of variables */
|
|
if (nvars)
|
|
memcpy(localvars, vars, sizeof(vars[0]) * nvars);
|
|
|
|
if ((flag & H_NOCLEAR) == 0) {
|
|
/* Destroy old hash table if one exists */
|
|
debug("Destroy Hash Table: %p table = %p\n", htab,
|
|
htab->table);
|
|
if (htab->table)
|
|
hdestroy_r(htab);
|
|
}
|
|
|
|
/*
|
|
* Create new hash table (if needed). The computation of the hash
|
|
* table size is based on heuristics: in a sample of some 70+
|
|
* existing systems we found an average size of 39+ bytes per entry
|
|
* in the environment (for the whole key=value pair). Assuming a
|
|
* size of 8 per entry (= safety factor of ~5) should provide enough
|
|
* safety margin for any existing environment definitions and still
|
|
* allow for more than enough dynamic additions. Note that the
|
|
* "size" argument is supposed to give the maximum environment size
|
|
* (CONFIG_ENV_SIZE). This heuristics will result in
|
|
* unreasonably large numbers (and thus memory footprint) for
|
|
* big flash environments (>8,000 entries for 64 KB
|
|
* envrionment size), so we clip it to a reasonable value.
|
|
* On the other hand we need to add some more entries for free
|
|
* space when importing very small buffers. Both boundaries can
|
|
* be overwritten in the board config file if needed.
|
|
*/
|
|
|
|
if (!htab->table) {
|
|
int nent = CONFIG_ENV_MIN_ENTRIES + size / 8;
|
|
|
|
if (nent > CONFIG_ENV_MAX_ENTRIES)
|
|
nent = CONFIG_ENV_MAX_ENTRIES;
|
|
|
|
debug("Create Hash Table: N=%d\n", nent);
|
|
|
|
if (hcreate_r(nent, htab) == 0) {
|
|
free(data);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Parse environment; allow for '\0' and 'sep' as separators */
|
|
do {
|
|
ENTRY e, *rv;
|
|
|
|
/* skip leading white space */
|
|
while (isblank(*dp))
|
|
++dp;
|
|
|
|
/* skip comment lines */
|
|
if (*dp == '#') {
|
|
while (*dp && (*dp != sep))
|
|
++dp;
|
|
++dp;
|
|
continue;
|
|
}
|
|
|
|
/* parse name */
|
|
for (name = dp; *dp != '=' && *dp && *dp != sep; ++dp)
|
|
;
|
|
|
|
/* deal with "name" and "name=" entries (delete var) */
|
|
if (*dp == '\0' || *(dp + 1) == '\0' ||
|
|
*dp == sep || *(dp + 1) == sep) {
|
|
if (*dp == '=')
|
|
*dp++ = '\0';
|
|
*dp++ = '\0'; /* terminate name */
|
|
|
|
debug("DELETE CANDIDATE: \"%s\"\n", name);
|
|
if (!drop_var_from_set(name, nvars, localvars))
|
|
continue;
|
|
|
|
if (hdelete_r(name, htab, flag) == 0)
|
|
debug("DELETE ERROR ##############################\n");
|
|
|
|
continue;
|
|
}
|
|
*dp++ = '\0'; /* terminate name */
|
|
|
|
/* parse value; deal with escapes */
|
|
for (value = sp = dp; *dp && (*dp != sep); ++dp) {
|
|
if ((*dp == '\\') && *(dp + 1))
|
|
++dp;
|
|
*sp++ = *dp;
|
|
}
|
|
*sp++ = '\0'; /* terminate value */
|
|
++dp;
|
|
|
|
if (*name == 0) {
|
|
debug("INSERT: unable to use an empty key\n");
|
|
__set_errno(EINVAL);
|
|
return 0;
|
|
}
|
|
|
|
/* Skip variables which are not supposed to be processed */
|
|
if (!drop_var_from_set(name, nvars, localvars))
|
|
continue;
|
|
|
|
/* enter into hash table */
|
|
e.key = name;
|
|
e.data = value;
|
|
|
|
hsearch_r(e, ENTER, &rv, htab, flag);
|
|
if (rv == NULL)
|
|
printf("himport_r: can't insert \"%s=%s\" into hash table\n",
|
|
name, value);
|
|
|
|
debug("INSERT: table %p, filled %d/%d rv %p ==> name=\"%s\" value=\"%s\"\n",
|
|
htab, htab->filled, htab->size,
|
|
rv, name, value);
|
|
} while ((dp < data + size) && *dp); /* size check needed for text */
|
|
/* without '\0' termination */
|
|
debug("INSERT: free(data = %p)\n", data);
|
|
free(data);
|
|
|
|
/* process variables which were not considered */
|
|
for (i = 0; i < nvars; i++) {
|
|
if (localvars[i] == NULL)
|
|
continue;
|
|
/*
|
|
* All variables which were not deleted from the variable list
|
|
* were not present in the imported env
|
|
* This could mean two things:
|
|
* a) if the variable was present in current env, we delete it
|
|
* b) if the variable was not present in current env, we notify
|
|
* it might be a typo
|
|
*/
|
|
if (hdelete_r(localvars[i], htab, flag) == 0)
|
|
printf("WARNING: '%s' neither in running nor in imported env!\n", localvars[i]);
|
|
else
|
|
printf("WARNING: '%s' not in imported env, deleting it!\n", localvars[i]);
|
|
}
|
|
|
|
debug("INSERT: done\n");
|
|
return 1; /* everything OK */
|
|
}
|
|
|
|
/*
|
|
* hwalk_r()
|
|
*/
|
|
|
|
/*
|
|
* Walk all of the entries in the hash, calling the callback for each one.
|
|
* this allows some generic operation to be performed on each element.
|
|
*/
|
|
int hwalk_r(struct hsearch_data *htab, int (*callback)(ENTRY *))
|
|
{
|
|
int i;
|
|
int retval;
|
|
|
|
for (i = 1; i <= htab->size; ++i) {
|
|
if (htab->table[i].used > 0) {
|
|
retval = callback(&htab->table[i].entry);
|
|
if (retval)
|
|
return retval;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|