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Diffstat (limited to 'tables/apr_tables.c')
| -rw-r--r-- | tables/apr_tables.c | 1300 |
1 files changed, 1300 insertions, 0 deletions
diff --git a/tables/apr_tables.c b/tables/apr_tables.c new file mode 100644 index 0000000..9dc594c --- /dev/null +++ b/tables/apr_tables.c @@ -0,0 +1,1300 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/* + * Resource allocation code... the code here is responsible for making + * sure that nothing leaks. + * + * rst --- 4/95 --- 6/95 + */ + +#include "apr_private.h" + +#include "apr_general.h" +#include "apr_pools.h" +#include "apr_tables.h" +#include "apr_strings.h" +#include "apr_lib.h" +#if APR_HAVE_STDLIB_H +#include <stdlib.h> +#endif +#if APR_HAVE_STRING_H +#include <string.h> +#endif +#if APR_HAVE_STRINGS_H +#include <strings.h> +#endif + +#if (APR_POOL_DEBUG || defined(MAKE_TABLE_PROFILE)) && APR_HAVE_STDIO_H +#include <stdio.h> +#endif + +/***************************************************************** + * This file contains array and apr_table_t functions only. + */ + +/***************************************************************** + * + * The 'array' functions... + */ + +static void make_array_core(apr_array_header_t *res, apr_pool_t *p, + int nelts, int elt_size, int clear) +{ + /* + * Assure sanity if someone asks for + * array of zero elts. + */ + if (nelts < 1) { + nelts = 1; + } + + if (clear) { + res->elts = apr_pcalloc(p, nelts * elt_size); + } + else { + res->elts = apr_palloc(p, nelts * elt_size); + } + + res->pool = p; + res->elt_size = elt_size; + res->nelts = 0; /* No active elements yet... */ + res->nalloc = nelts; /* ...but this many allocated */ +} + +APR_DECLARE(int) apr_is_empty_array(const apr_array_header_t *a) +{ + return ((a == NULL) || (a->nelts == 0)); +} + +APR_DECLARE(apr_array_header_t *) apr_array_make(apr_pool_t *p, + int nelts, int elt_size) +{ + apr_array_header_t *res; + + res = (apr_array_header_t *) apr_palloc(p, sizeof(apr_array_header_t)); + make_array_core(res, p, nelts, elt_size, 1); + return res; +} + +APR_DECLARE(void) apr_array_clear(apr_array_header_t *arr) +{ + arr->nelts = 0; +} + +APR_DECLARE(void *) apr_array_pop(apr_array_header_t *arr) +{ + if (apr_is_empty_array(arr)) { + return NULL; + } + + return arr->elts + (arr->elt_size * (--arr->nelts)); +} + +APR_DECLARE(void *) apr_array_push(apr_array_header_t *arr) +{ + if (arr->nelts == arr->nalloc) { + int new_size = (arr->nalloc <= 0) ? 1 : arr->nalloc * 2; + char *new_data; + + new_data = apr_palloc(arr->pool, arr->elt_size * new_size); + + memcpy(new_data, arr->elts, arr->nalloc * arr->elt_size); + memset(new_data + arr->nalloc * arr->elt_size, 0, + arr->elt_size * (new_size - arr->nalloc)); + arr->elts = new_data; + arr->nalloc = new_size; + } + + ++arr->nelts; + return arr->elts + (arr->elt_size * (arr->nelts - 1)); +} + +static void *apr_array_push_noclear(apr_array_header_t *arr) +{ + if (arr->nelts == arr->nalloc) { + int new_size = (arr->nalloc <= 0) ? 1 : arr->nalloc * 2; + char *new_data; + + new_data = apr_palloc(arr->pool, arr->elt_size * new_size); + + memcpy(new_data, arr->elts, arr->nalloc * arr->elt_size); + arr->elts = new_data; + arr->nalloc = new_size; + } + + ++arr->nelts; + return arr->elts + (arr->elt_size * (arr->nelts - 1)); +} + +APR_DECLARE(void) apr_array_cat(apr_array_header_t *dst, + const apr_array_header_t *src) +{ + int elt_size = dst->elt_size; + + if (dst->nelts + src->nelts > dst->nalloc) { + int new_size = (dst->nalloc <= 0) ? 1 : dst->nalloc * 2; + char *new_data; + + while (dst->nelts + src->nelts > new_size) { + new_size *= 2; + } + + new_data = apr_pcalloc(dst->pool, elt_size * new_size); + memcpy(new_data, dst->elts, dst->nalloc * elt_size); + + dst->elts = new_data; + dst->nalloc = new_size; + } + + memcpy(dst->elts + dst->nelts * elt_size, src->elts, + elt_size * src->nelts); + dst->nelts += src->nelts; +} + +APR_DECLARE(apr_array_header_t *) apr_array_copy(apr_pool_t *p, + const apr_array_header_t *arr) +{ + apr_array_header_t *res = + (apr_array_header_t *) apr_palloc(p, sizeof(apr_array_header_t)); + make_array_core(res, p, arr->nalloc, arr->elt_size, 0); + + memcpy(res->elts, arr->elts, arr->elt_size * arr->nelts); + res->nelts = arr->nelts; + memset(res->elts + res->elt_size * res->nelts, 0, + res->elt_size * (res->nalloc - res->nelts)); + return res; +} + +/* This cute function copies the array header *only*, but arranges + * for the data section to be copied on the first push or arraycat. + * It's useful when the elements of the array being copied are + * read only, but new stuff *might* get added on the end; we have the + * overhead of the full copy only where it is really needed. + */ + +static APR_INLINE void copy_array_hdr_core(apr_array_header_t *res, + const apr_array_header_t *arr) +{ + res->elts = arr->elts; + res->elt_size = arr->elt_size; + res->nelts = arr->nelts; + res->nalloc = arr->nelts; /* Force overflow on push */ +} + +APR_DECLARE(apr_array_header_t *) + apr_array_copy_hdr(apr_pool_t *p, + const apr_array_header_t *arr) +{ + apr_array_header_t *res; + + res = (apr_array_header_t *) apr_palloc(p, sizeof(apr_array_header_t)); + res->pool = p; + copy_array_hdr_core(res, arr); + return res; +} + +/* The above is used here to avoid consing multiple new array bodies... */ + +APR_DECLARE(apr_array_header_t *) + apr_array_append(apr_pool_t *p, + const apr_array_header_t *first, + const apr_array_header_t *second) +{ + apr_array_header_t *res = apr_array_copy_hdr(p, first); + + apr_array_cat(res, second); + return res; +} + +/* apr_array_pstrcat generates a new string from the apr_pool_t containing + * the concatenated sequence of substrings referenced as elements within + * the array. The string will be empty if all substrings are empty or null, + * or if there are no elements in the array. + * If sep is non-NUL, it will be inserted between elements as a separator. + */ +APR_DECLARE(char *) apr_array_pstrcat(apr_pool_t *p, + const apr_array_header_t *arr, + const char sep) +{ + char *cp, *res, **strpp; + apr_size_t len; + int i; + + if (arr->nelts <= 0 || arr->elts == NULL) { /* Empty table? */ + return (char *) apr_pcalloc(p, 1); + } + + /* Pass one --- find length of required string */ + + len = 0; + for (i = 0, strpp = (char **) arr->elts; ; ++strpp) { + if (strpp && *strpp != NULL) { + len += strlen(*strpp); + } + if (++i >= arr->nelts) { + break; + } + if (sep) { + ++len; + } + } + + /* Allocate the required string */ + + res = (char *) apr_palloc(p, len + 1); + cp = res; + + /* Pass two --- copy the argument strings into the result space */ + + for (i = 0, strpp = (char **) arr->elts; ; ++strpp) { + if (strpp && *strpp != NULL) { + len = strlen(*strpp); + memcpy(cp, *strpp, len); + cp += len; + } + if (++i >= arr->nelts) { + break; + } + if (sep) { + *cp++ = sep; + } + } + + *cp = '\0'; + + /* Return the result string */ + + return res; +} + + +/***************************************************************** + * + * The "table" functions. + */ + +#if APR_CHARSET_EBCDIC +#define CASE_MASK 0xbfbfbfbf +#else +#define CASE_MASK 0xdfdfdfdf +#endif + +#define TABLE_HASH_SIZE 32 +#define TABLE_INDEX_MASK 0x1f +#define TABLE_HASH(key) (TABLE_INDEX_MASK & *(unsigned char *)(key)) +#define TABLE_INDEX_IS_INITIALIZED(t, i) ((t)->index_initialized & (1u << (i))) +#define TABLE_SET_INDEX_INITIALIZED(t, i) ((t)->index_initialized |= (1u << (i))) + +/* Compute the "checksum" for a key, consisting of the first + * 4 bytes, normalized for case-insensitivity and packed into + * an int...this checksum allows us to do a single integer + * comparison as a fast check to determine whether we can + * skip a strcasecmp + */ +#define COMPUTE_KEY_CHECKSUM(key, checksum) \ +{ \ + const char *k = (key); \ + apr_uint32_t c = (apr_uint32_t)*k; \ + (checksum) = c; \ + (checksum) <<= 8; \ + if (c) { \ + c = (apr_uint32_t)*++k; \ + checksum |= c; \ + } \ + (checksum) <<= 8; \ + if (c) { \ + c = (apr_uint32_t)*++k; \ + checksum |= c; \ + } \ + (checksum) <<= 8; \ + if (c) { \ + c = (apr_uint32_t)*++k; \ + checksum |= c; \ + } \ + checksum &= CASE_MASK; \ +} + +/** The opaque string-content table type */ +struct apr_table_t { + /* This has to be first to promote backwards compatibility with + * older modules which cast a apr_table_t * to an apr_array_header_t *... + * they should use the apr_table_elts() function for most of the + * cases they do this for. + */ + /** The underlying array for the table */ + apr_array_header_t a; +#ifdef MAKE_TABLE_PROFILE + /** Who created the array. */ + void *creator; +#endif + /* An index to speed up table lookups. The way this works is: + * - Hash the key into the index: + * - index_first[TABLE_HASH(key)] is the offset within + * the table of the first entry with that key + * - index_last[TABLE_HASH(key)] is the offset within + * the table of the last entry with that key + * - If (and only if) there is no entry in the table whose + * key hashes to index element i, then the i'th bit + * of index_initialized will be zero. (Check this before + * trying to use index_first[i] or index_last[i]!) + */ + apr_uint32_t index_initialized; + int index_first[TABLE_HASH_SIZE]; + int index_last[TABLE_HASH_SIZE]; +}; + +/* keep state for apr_table_getm() */ +typedef struct +{ + apr_pool_t *p; + const char *first; + apr_array_header_t *merged; +} table_getm_t; + +/* + * NOTICE: if you tweak this you should look at is_empty_table() + * and table_elts() in alloc.h + */ +#ifdef MAKE_TABLE_PROFILE +static apr_table_entry_t *do_table_push(const char *func, apr_table_t *t) +{ + if (t->a.nelts == t->a.nalloc) { + fprintf(stderr, "%s: table created by %p hit limit of %u\n", + func ? func : "table_push", t->creator, t->a.nalloc); + } + return (apr_table_entry_t *) apr_array_push_noclear(&t->a); +} +#if defined(__GNUC__) && __GNUC__ >= 2 +#define table_push(t) do_table_push(__FUNCTION__, t) +#else +#define table_push(t) do_table_push(NULL, t) +#endif +#else /* MAKE_TABLE_PROFILE */ +#define table_push(t) ((apr_table_entry_t *) apr_array_push_noclear(&(t)->a)) +#endif /* MAKE_TABLE_PROFILE */ + +APR_DECLARE(const apr_array_header_t *) apr_table_elts(const apr_table_t *t) +{ + return (const apr_array_header_t *)t; +} + +APR_DECLARE(int) apr_is_empty_table(const apr_table_t *t) +{ + return ((t == NULL) || (t->a.nelts == 0)); +} + +APR_DECLARE(apr_table_t *) apr_table_make(apr_pool_t *p, int nelts) +{ + apr_table_t *t = apr_palloc(p, sizeof(apr_table_t)); + + make_array_core(&t->a, p, nelts, sizeof(apr_table_entry_t), 0); +#ifdef MAKE_TABLE_PROFILE + t->creator = __builtin_return_address(0); +#endif + t->index_initialized = 0; + return t; +} + +APR_DECLARE(apr_table_t *) apr_table_copy(apr_pool_t *p, const apr_table_t *t) +{ + apr_table_t *new = apr_palloc(p, sizeof(apr_table_t)); + +#if APR_POOL_DEBUG + /* we don't copy keys and values, so it's necessary that t->a.pool + * have a life span at least as long as p + */ + if (!apr_pool_is_ancestor(t->a.pool, p)) { + fprintf(stderr, "apr_table_copy: t's pool is not an ancestor of p\n"); + abort(); + } +#endif + make_array_core(&new->a, p, t->a.nalloc, sizeof(apr_table_entry_t), 0); + memcpy(new->a.elts, t->a.elts, t->a.nelts * sizeof(apr_table_entry_t)); + new->a.nelts = t->a.nelts; + memcpy(new->index_first, t->index_first, sizeof(int) * TABLE_HASH_SIZE); + memcpy(new->index_last, t->index_last, sizeof(int) * TABLE_HASH_SIZE); + new->index_initialized = t->index_initialized; + return new; +} + +APR_DECLARE(apr_table_t *) apr_table_clone(apr_pool_t *p, const apr_table_t *t) +{ + const apr_array_header_t *array = apr_table_elts(t); + apr_table_entry_t *elts = (apr_table_entry_t *) array->elts; + apr_table_t *new = apr_table_make(p, array->nelts); + int i; + + for (i = 0; i < array->nelts; i++) { + apr_table_add(new, elts[i].key, elts[i].val); + } + + return new; +} + +static void table_reindex(apr_table_t *t) +{ + int i; + int hash; + apr_table_entry_t *next_elt = (apr_table_entry_t *) t->a.elts; + + t->index_initialized = 0; + for (i = 0; i < t->a.nelts; i++, next_elt++) { + hash = TABLE_HASH(next_elt->key); + t->index_last[hash] = i; + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = i; + TABLE_SET_INDEX_INITIALIZED(t, hash); + } + } +} + +APR_DECLARE(void) apr_table_clear(apr_table_t *t) +{ + t->a.nelts = 0; + t->index_initialized = 0; +} + +APR_DECLARE(const char *) apr_table_get(const apr_table_t *t, const char *key) +{ + apr_table_entry_t *next_elt; + apr_table_entry_t *end_elt; + apr_uint32_t checksum; + int hash; + + if (key == NULL) { + return NULL; + } + + hash = TABLE_HASH(key); + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + return NULL; + } + COMPUTE_KEY_CHECKSUM(key, checksum); + next_elt = ((apr_table_entry_t *) t->a.elts) + t->index_first[hash];; + end_elt = ((apr_table_entry_t *) t->a.elts) + t->index_last[hash]; + + for (; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + return next_elt->val; + } + } + + return NULL; +} + +APR_DECLARE(void) apr_table_set(apr_table_t *t, const char *key, + const char *val) +{ + apr_table_entry_t *next_elt; + apr_table_entry_t *end_elt; + apr_table_entry_t *table_end; + apr_uint32_t checksum; + int hash; + + COMPUTE_KEY_CHECKSUM(key, checksum); + hash = TABLE_HASH(key); + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = t->a.nelts; + TABLE_SET_INDEX_INITIALIZED(t, hash); + goto add_new_elt; + } + next_elt = ((apr_table_entry_t *) t->a.elts) + t->index_first[hash];; + end_elt = ((apr_table_entry_t *) t->a.elts) + t->index_last[hash]; + table_end =((apr_table_entry_t *) t->a.elts) + t->a.nelts; + + for (; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + + /* Found an existing entry with the same key, so overwrite it */ + + int must_reindex = 0; + apr_table_entry_t *dst_elt = NULL; + + next_elt->val = apr_pstrdup(t->a.pool, val); + + /* Remove any other instances of this key */ + for (next_elt++; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + t->a.nelts--; + if (!dst_elt) { + dst_elt = next_elt; + } + } + else if (dst_elt) { + *dst_elt++ = *next_elt; + must_reindex = 1; + } + } + + /* If we've removed anything, shift over the remainder + * of the table (note that the previous loop didn't + * run to the end of the table, just to the last match + * for the index) + */ + if (dst_elt) { + for (; next_elt < table_end; next_elt++) { + *dst_elt++ = *next_elt; + } + must_reindex = 1; + } + if (must_reindex) { + table_reindex(t); + } + return; + } + } + +add_new_elt: + t->index_last[hash] = t->a.nelts; + next_elt = (apr_table_entry_t *) table_push(t); + next_elt->key = apr_pstrdup(t->a.pool, key); + next_elt->val = apr_pstrdup(t->a.pool, val); + next_elt->key_checksum = checksum; +} + +APR_DECLARE(void) apr_table_setn(apr_table_t *t, const char *key, + const char *val) +{ + apr_table_entry_t *next_elt; + apr_table_entry_t *end_elt; + apr_table_entry_t *table_end; + apr_uint32_t checksum; + int hash; + + COMPUTE_KEY_CHECKSUM(key, checksum); + hash = TABLE_HASH(key); + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = t->a.nelts; + TABLE_SET_INDEX_INITIALIZED(t, hash); + goto add_new_elt; + } + next_elt = ((apr_table_entry_t *) t->a.elts) + t->index_first[hash];; + end_elt = ((apr_table_entry_t *) t->a.elts) + t->index_last[hash]; + table_end =((apr_table_entry_t *) t->a.elts) + t->a.nelts; + + for (; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + + /* Found an existing entry with the same key, so overwrite it */ + + int must_reindex = 0; + apr_table_entry_t *dst_elt = NULL; + + next_elt->val = (char *)val; + + /* Remove any other instances of this key */ + for (next_elt++; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + t->a.nelts--; + if (!dst_elt) { + dst_elt = next_elt; + } + } + else if (dst_elt) { + *dst_elt++ = *next_elt; + must_reindex = 1; + } + } + + /* If we've removed anything, shift over the remainder + * of the table (note that the previous loop didn't + * run to the end of the table, just to the last match + * for the index) + */ + if (dst_elt) { + for (; next_elt < table_end; next_elt++) { + *dst_elt++ = *next_elt; + } + must_reindex = 1; + } + if (must_reindex) { + table_reindex(t); + } + return; + } + } + +add_new_elt: + t->index_last[hash] = t->a.nelts; + next_elt = (apr_table_entry_t *) table_push(t); + next_elt->key = (char *)key; + next_elt->val = (char *)val; + next_elt->key_checksum = checksum; +} + +APR_DECLARE(void) apr_table_unset(apr_table_t *t, const char *key) +{ + apr_table_entry_t *next_elt; + apr_table_entry_t *end_elt; + apr_table_entry_t *dst_elt; + apr_uint32_t checksum; + int hash; + int must_reindex; + + hash = TABLE_HASH(key); + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + return; + } + COMPUTE_KEY_CHECKSUM(key, checksum); + next_elt = ((apr_table_entry_t *) t->a.elts) + t->index_first[hash]; + end_elt = ((apr_table_entry_t *) t->a.elts) + t->index_last[hash]; + must_reindex = 0; + for (; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + + /* Found a match: remove this entry, plus any additional + * matches for the same key that might follow + */ + apr_table_entry_t *table_end = ((apr_table_entry_t *) t->a.elts) + + t->a.nelts; + t->a.nelts--; + dst_elt = next_elt; + for (next_elt++; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + t->a.nelts--; + } + else { + *dst_elt++ = *next_elt; + } + } + + /* Shift over the remainder of the table (note that + * the previous loop didn't run to the end of the table, + * just to the last match for the index) + */ + for (; next_elt < table_end; next_elt++) { + *dst_elt++ = *next_elt; + } + must_reindex = 1; + break; + } + } + if (must_reindex) { + table_reindex(t); + } +} + +APR_DECLARE(void) apr_table_merge(apr_table_t *t, const char *key, + const char *val) +{ + apr_table_entry_t *next_elt; + apr_table_entry_t *end_elt; + apr_uint32_t checksum; + int hash; + + COMPUTE_KEY_CHECKSUM(key, checksum); + hash = TABLE_HASH(key); + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = t->a.nelts; + TABLE_SET_INDEX_INITIALIZED(t, hash); + goto add_new_elt; + } + next_elt = ((apr_table_entry_t *) t->a.elts) + t->index_first[hash]; + end_elt = ((apr_table_entry_t *) t->a.elts) + t->index_last[hash]; + + for (; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + + /* Found an existing entry with the same key, so merge with it */ + next_elt->val = apr_pstrcat(t->a.pool, next_elt->val, ", ", + val, NULL); + return; + } + } + +add_new_elt: + t->index_last[hash] = t->a.nelts; + next_elt = (apr_table_entry_t *) table_push(t); + next_elt->key = apr_pstrdup(t->a.pool, key); + next_elt->val = apr_pstrdup(t->a.pool, val); + next_elt->key_checksum = checksum; +} + +APR_DECLARE(void) apr_table_mergen(apr_table_t *t, const char *key, + const char *val) +{ + apr_table_entry_t *next_elt; + apr_table_entry_t *end_elt; + apr_uint32_t checksum; + int hash; + +#if APR_POOL_DEBUG + { + apr_pool_t *pool; + pool = apr_pool_find(key); + if ((pool != (apr_pool_t *)key) + && (!apr_pool_is_ancestor(pool, t->a.pool))) { + fprintf(stderr, "apr_table_mergen: key not in ancestor pool of t\n"); + abort(); + } + pool = apr_pool_find(val); + if ((pool != (apr_pool_t *)val) + && (!apr_pool_is_ancestor(pool, t->a.pool))) { + fprintf(stderr, "apr_table_mergen: val not in ancestor pool of t\n"); + abort(); + } + } +#endif + + COMPUTE_KEY_CHECKSUM(key, checksum); + hash = TABLE_HASH(key); + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = t->a.nelts; + TABLE_SET_INDEX_INITIALIZED(t, hash); + goto add_new_elt; + } + next_elt = ((apr_table_entry_t *) t->a.elts) + t->index_first[hash];; + end_elt = ((apr_table_entry_t *) t->a.elts) + t->index_last[hash]; + + for (; next_elt <= end_elt; next_elt++) { + if ((checksum == next_elt->key_checksum) && + !strcasecmp(next_elt->key, key)) { + + /* Found an existing entry with the same key, so merge with it */ + next_elt->val = apr_pstrcat(t->a.pool, next_elt->val, ", ", + val, NULL); + return; + } + } + +add_new_elt: + t->index_last[hash] = t->a.nelts; + next_elt = (apr_table_entry_t *) table_push(t); + next_elt->key = (char *)key; + next_elt->val = (char *)val; + next_elt->key_checksum = checksum; +} + +APR_DECLARE(void) apr_table_add(apr_table_t *t, const char *key, + const char *val) +{ + apr_table_entry_t *elts; + apr_uint32_t checksum; + int hash; + + hash = TABLE_HASH(key); + t->index_last[hash] = t->a.nelts; + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = t->a.nelts; + TABLE_SET_INDEX_INITIALIZED(t, hash); + } + COMPUTE_KEY_CHECKSUM(key, checksum); + elts = (apr_table_entry_t *) table_push(t); + elts->key = apr_pstrdup(t->a.pool, key); + elts->val = apr_pstrdup(t->a.pool, val); + elts->key_checksum = checksum; +} + +APR_DECLARE(void) apr_table_addn(apr_table_t *t, const char *key, + const char *val) +{ + apr_table_entry_t *elts; + apr_uint32_t checksum; + int hash; + +#if APR_POOL_DEBUG + { + if (!apr_pool_is_ancestor(apr_pool_find(key), t->a.pool)) { + fprintf(stderr, "apr_table_addn: key not in ancestor pool of t\n"); + abort(); + } + if (!apr_pool_is_ancestor(apr_pool_find(val), t->a.pool)) { + fprintf(stderr, "apr_table_addn: val not in ancestor pool of t\n"); + abort(); + } + } +#endif + + hash = TABLE_HASH(key); + t->index_last[hash] = t->a.nelts; + if (!TABLE_INDEX_IS_INITIALIZED(t, hash)) { + t->index_first[hash] = t->a.nelts; + TABLE_SET_INDEX_INITIALIZED(t, hash); + } + COMPUTE_KEY_CHECKSUM(key, checksum); + elts = (apr_table_entry_t *) table_push(t); + elts->key = (char *)key; + elts->val = (char *)val; + elts->key_checksum = checksum; +} + +APR_DECLARE(apr_table_t *) apr_table_overlay(apr_pool_t *p, + const apr_table_t *overlay, + const apr_table_t *base) +{ + apr_table_t *res; + +#if APR_POOL_DEBUG + /* we don't copy keys and values, so it's necessary that + * overlay->a.pool and base->a.pool have a life span at least + * as long as p + */ + if (!apr_pool_is_ancestor(overlay->a.pool, p)) { + fprintf(stderr, + "apr_table_overlay: overlay's pool is not an ancestor of p\n"); + abort(); + } + if (!apr_pool_is_ancestor(base->a.pool, p)) { + fprintf(stderr, + "apr_table_overlay: base's pool is not an ancestor of p\n"); + abort(); + } +#endif + + res = apr_palloc(p, sizeof(apr_table_t)); + /* behave like append_arrays */ + res->a.pool = p; + copy_array_hdr_core(&res->a, &overlay->a); + apr_array_cat(&res->a, &base->a); + table_reindex(res); + return res; +} + +/* And now for something completely abstract ... + + * For each key value given as a vararg: + * run the function pointed to as + * int comp(void *r, char *key, char *value); + * on each valid key-value pair in the apr_table_t t that matches the vararg key, + * or once for every valid key-value pair if the vararg list is empty, + * until the function returns false (0) or we finish the table. + * + * Note that we restart the traversal for each vararg, which means that + * duplicate varargs will result in multiple executions of the function + * for each matching key. Note also that if the vararg list is empty, + * only one traversal will be made and will cut short if comp returns 0. + * + * Note that the table_get and table_merge functions assume that each key in + * the apr_table_t is unique (i.e., no multiple entries with the same key). This + * function does not make that assumption, since it (unfortunately) isn't + * true for some of Apache's tables. + * + * Note that rec is simply passed-on to the comp function, so that the + * caller can pass additional info for the task. + * + * ADDENDUM for apr_table_vdo(): + * + * The caching api will allow a user to walk the header values: + * + * apr_status_t apr_cache_el_header_walk(apr_cache_el *el, + * int (*comp)(void *, const char *, const char *), void *rec, ...); + * + * So it can be ..., however from there I use a callback that use a va_list: + * + * apr_status_t (*cache_el_header_walk)(apr_cache_el *el, + * int (*comp)(void *, const char *, const char *), void *rec, va_list); + * + * To pass those ...'s on down to the actual module that will handle walking + * their headers, in the file case this is actually just an apr_table - and + * rather than reimplementing apr_table_do (which IMHO would be bad) I just + * called it with the va_list. For mod_shmem_cache I don't need it since I + * can't use apr_table's, but mod_file_cache should (though a good hash would + * be better, but that's a different issue :). + * + * So to make mod_file_cache easier to maintain, it's a good thing + */ +APR_DECLARE_NONSTD(int) apr_table_do(apr_table_do_callback_fn_t *comp, + void *rec, const apr_table_t *t, ...) +{ + int rv; + + va_list vp; + va_start(vp, t); + rv = apr_table_vdo(comp, rec, t, vp); + va_end(vp); + + return rv; +} + +/* XXX: do the semantics of this routine make any sense? Right now, + * if the caller passed in a non-empty va_list of keys to search for, + * the "early termination" facility only terminates on *that* key; other + * keys will continue to process. Note that this only has any effect + * at all if there are multiple entries in the table with the same key, + * otherwise the called function can never effectively early-terminate + * this function, as the zero return value is effectively ignored. + * + * Note also that this behavior is at odds with the behavior seen if an + * empty va_list is passed in -- in that case, a zero return value terminates + * the entire apr_table_vdo (which is what I think should happen in + * both cases). + * + * If nobody objects soon, I'm going to change the order of the nested + * loops in this function so that any zero return value from the (*comp) + * function will cause a full termination of apr_table_vdo. I'm hesitant + * at the moment because these (funky) semantics have been around for a + * very long time, and although Apache doesn't seem to use them at all, + * some third-party vendor might. I can only think of one possible reason + * the existing semantics would make any sense, and it's very Apache-centric, + * which is this: if (*comp) is looking for matches of a particular + * substring in request headers (let's say it's looking for a particular + * cookie name in the Set-Cookie headers), then maybe it wants to be + * able to stop searching early as soon as it finds that one and move + * on to the next key. That's only an optimization of course, but changing + * the behavior of this function would mean that any code that tried + * to do that would stop working right. + * + * Sigh. --JCW, 06/28/02 + */ +APR_DECLARE(int) apr_table_vdo(apr_table_do_callback_fn_t *comp, + void *rec, const apr_table_t *t, va_list vp) +{ + char *argp; + apr_table_entry_t *elts = (apr_table_entry_t *) t->a.elts; + int vdorv = 1; + + argp = va_arg(vp, char *); + do { + int rv = 1, i; + if (argp) { + /* Scan for entries that match the next key */ + int hash = TABLE_HASH(argp); + if (TABLE_INDEX_IS_INITIALIZED(t, hash)) { + apr_uint32_t checksum; + COMPUTE_KEY_CHECKSUM(argp, checksum); + for (i = t->index_first[hash]; + rv && (i <= t->index_last[hash]); ++i) { + if (elts[i].key && (checksum == elts[i].key_checksum) && + !strcasecmp(elts[i].key, argp)) { + rv = (*comp) (rec, elts[i].key, elts[i].val); + } + } + } + } + else { + /* Scan the entire table */ + for (i = 0; rv && (i < t->a.nelts); ++i) { + if (elts[i].key) { + rv = (*comp) (rec, elts[i].key, elts[i].val); + } + } + } + if (rv == 0) { + vdorv = 0; + } + } while (argp && ((argp = va_arg(vp, char *)) != NULL)); + + return vdorv; +} + +static apr_table_entry_t **table_mergesort(apr_pool_t *pool, + apr_table_entry_t **values, + apr_size_t n) +{ + /* Bottom-up mergesort, based on design in Sedgewick's "Algorithms + * in C," chapter 8 + */ + apr_table_entry_t **values_tmp = + (apr_table_entry_t **)apr_palloc(pool, n * sizeof(apr_table_entry_t*)); + apr_size_t i; + apr_size_t blocksize; + + /* First pass: sort pairs of elements (blocksize=1) */ + for (i = 0; i + 1 < n; i += 2) { + if (strcasecmp(values[i]->key, values[i + 1]->key) > 0) { + apr_table_entry_t *swap = values[i]; + values[i] = values[i + 1]; + values[i + 1] = swap; + } + } + + /* Merge successively larger blocks */ + blocksize = 2; + while (blocksize < n) { + apr_table_entry_t **dst = values_tmp; + apr_size_t next_start; + apr_table_entry_t **swap; + + /* Merge consecutive pairs blocks of the next blocksize. + * Within a block, elements are in sorted order due to + * the previous iteration. + */ + for (next_start = 0; next_start + blocksize < n; + next_start += (blocksize + blocksize)) { + + apr_size_t block1_start = next_start; + apr_size_t block2_start = block1_start + blocksize; + apr_size_t block1_end = block2_start; + apr_size_t block2_end = block2_start + blocksize; + if (block2_end > n) { + /* The last block may be smaller than blocksize */ + block2_end = n; + } + for (;;) { + + /* Merge the next two blocks: + * Pick the smaller of the next element from + * block 1 and the next element from block 2. + * Once either of the blocks is emptied, copy + * over all the remaining elements from the + * other block + */ + if (block1_start == block1_end) { + for (; block2_start < block2_end; block2_start++) { + *dst++ = values[block2_start]; + } + break; + } + else if (block2_start == block2_end) { + for (; block1_start < block1_end; block1_start++) { + *dst++ = values[block1_start]; + } + break; + } + if (strcasecmp(values[block1_start]->key, + values[block2_start]->key) > 0) { + *dst++ = values[block2_start++]; + } + else { + *dst++ = values[block1_start++]; + } + } + } + + /* If n is not a multiple of 2*blocksize, some elements + * will be left over at the end of the array. + */ + for (i = dst - values_tmp; i < n; i++) { + values_tmp[i] = values[i]; + } + + /* The output array of this pass becomes the input + * array of the next pass, and vice versa + */ + swap = values_tmp; + values_tmp = values; + values = swap; + + blocksize += blocksize; + } + + return values; +} + +APR_DECLARE(void) apr_table_compress(apr_table_t *t, unsigned flags) +{ + apr_table_entry_t **sort_array; + apr_table_entry_t **sort_next; + apr_table_entry_t **sort_end; + apr_table_entry_t *table_next; + apr_table_entry_t **last; + int i; + int dups_found; + + if (flags == APR_OVERLAP_TABLES_ADD) { + return; + } + + if (t->a.nelts <= 1) { + return; + } + + /* Copy pointers to all the table elements into an + * array and sort to allow for easy detection of + * duplicate keys + */ + sort_array = (apr_table_entry_t **) + apr_palloc(t->a.pool, t->a.nelts * sizeof(apr_table_entry_t*)); + sort_next = sort_array; + table_next = (apr_table_entry_t *)t->a.elts; + i = t->a.nelts; + do { + *sort_next++ = table_next++; + } while (--i); + + /* Note: the merge is done with mergesort instead of quicksort + * because mergesort is a stable sort and runs in n*log(n) + * time regardless of its inputs (quicksort is quadratic in + * the worst case) + */ + sort_array = table_mergesort(t->a.pool, sort_array, t->a.nelts); + + /* Process any duplicate keys */ + dups_found = 0; + sort_next = sort_array; + sort_end = sort_array + t->a.nelts; + last = sort_next++; + while (sort_next < sort_end) { + if (((*sort_next)->key_checksum == (*last)->key_checksum) && + !strcasecmp((*sort_next)->key, (*last)->key)) { + apr_table_entry_t **dup_last = sort_next + 1; + dups_found = 1; + while ((dup_last < sort_end) && + ((*dup_last)->key_checksum == (*last)->key_checksum) && + !strcasecmp((*dup_last)->key, (*last)->key)) { + dup_last++; + } + dup_last--; /* Elements from last through dup_last, inclusive, + * all have the same key + */ + if (flags == APR_OVERLAP_TABLES_MERGE) { + apr_size_t len = 0; + apr_table_entry_t **next = last; + char *new_val; + char *val_dst; + do { + len += strlen((*next)->val); + len += 2; /* for ", " or trailing null */ + } while (++next <= dup_last); + new_val = (char *)apr_palloc(t->a.pool, len); + val_dst = new_val; + next = last; + for (;;) { + strcpy(val_dst, (*next)->val); + val_dst += strlen((*next)->val); + next++; + if (next > dup_last) { + *val_dst = 0; + break; + } + else { + *val_dst++ = ','; + *val_dst++ = ' '; + } + } + (*last)->val = new_val; + } + else { /* overwrite */ + (*last)->val = (*dup_last)->val; + } + do { + (*sort_next)->key = NULL; + } while (++sort_next <= dup_last); + } + else { + last = sort_next++; + } + } + + /* Shift elements to the left to fill holes left by removing duplicates */ + if (dups_found) { + apr_table_entry_t *src = (apr_table_entry_t *)t->a.elts; + apr_table_entry_t *dst = (apr_table_entry_t *)t->a.elts; + apr_table_entry_t *last_elt = src + t->a.nelts; + do { + if (src->key) { + *dst++ = *src; + } + } while (++src < last_elt); + t->a.nelts -= (int)(last_elt - dst); + } + + table_reindex(t); +} + +static void apr_table_cat(apr_table_t *t, const apr_table_t *s) +{ + const int n = t->a.nelts; + register int idx; + + apr_array_cat(&t->a,&s->a); + + if (n == 0) { + memcpy(t->index_first,s->index_first,sizeof(int) * TABLE_HASH_SIZE); + memcpy(t->index_last, s->index_last, sizeof(int) * TABLE_HASH_SIZE); + t->index_initialized = s->index_initialized; + return; + } + + for (idx = 0; idx < TABLE_HASH_SIZE; ++idx) { + if (TABLE_INDEX_IS_INITIALIZED(s, idx)) { + t->index_last[idx] = s->index_last[idx] + n; + if (!TABLE_INDEX_IS_INITIALIZED(t, idx)) { + t->index_first[idx] = s->index_first[idx] + n; + } + } + } + + t->index_initialized |= s->index_initialized; +} + +APR_DECLARE(void) apr_table_overlap(apr_table_t *a, const apr_table_t *b, + unsigned flags) +{ + if (a->a.nelts + b->a.nelts == 0) { + return; + } + +#if APR_POOL_DEBUG + /* Since the keys and values are not copied, it's required that + * b->a.pool has a lifetime at least as long as a->a.pool. */ + if (!apr_pool_is_ancestor(b->a.pool, a->a.pool)) { + fprintf(stderr, "apr_table_overlap: b's pool is not an ancestor of a's\n"); + abort(); + } +#endif + + apr_table_cat(a, b); + + apr_table_compress(a, flags); +} + +static int table_getm_do(void *v, const char *key, const char *val) +{ + table_getm_t *state = (table_getm_t *) v; + + if (!state->first) { + /** + * The most common case is a single header, and this is covered by + * a fast path that doesn't allocate any memory. On the second and + * subsequent header, an array is created and the array concatenated + * together to form the final value. + */ + state->first = val; + } + else { + const char **elt; + if (!state->merged) { + state->merged = apr_array_make(state->p, 10, sizeof(const char *)); + elt = apr_array_push(state->merged); + *elt = state->first; + } + elt = apr_array_push(state->merged); + *elt = val; + } + return 1; +} + +APR_DECLARE(const char *) apr_table_getm(apr_pool_t *p, const apr_table_t *t, + const char *key) +{ + table_getm_t state; + + state.p = p; + state.first = NULL; + state.merged = NULL; + + apr_table_do(table_getm_do, &state, t, key, NULL); + + if (!state.first) { + return NULL; + } + else if (!state.merged) { + return state.first; + } + else { + return apr_array_pstrcat(p, state.merged, ','); + } +} |