vector.h

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2013, Digium, Inc.
 *
 * David M. Lee, II <dlee@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
#ifndef _ASTERISK_VECTOR_H
#define _ASTERISK_VECTOR_H
 
#include "asterisk/lock.h"
 
/*! \file
 *
 * \brief Vector container support.
 *
 * A vector is a variable length array, with properties that can be useful when
 * order doesn't matter.
 *  - Appends are asymptotically constant time.
 *  - Unordered removes are constant time.
 *  - Search is linear time
 *
 * \author David M. Lee, II <dlee@digium.com>
 * \since 12
 */
 
/*!
 * \brief Define a vector structure
 *
 * \param name Optional vector struct name.
 * \param type Vector element type.
 */
#define AST_VECTOR(name, type)          \
    struct name {               \
        type *elems;            \
        size_t max;         \
        size_t current;         \
    }
 
/*! \brief Integer vector definition */
AST_VECTOR(ast_vector_int, int);
 
/*! \brief String vector definitions */
AST_VECTOR(ast_vector_string, char *);
AST_VECTOR(ast_vector_const_string, const char *);
 
/*! Options to override default processing of ast_vector_string_split. */
enum ast_vector_string_split_flags {
    /*! Do not trim whitespace from values. */
    AST_VECTOR_STRING_SPLIT_NO_TRIM = 0x01,
    /*! Append empty strings to the vector. */
    AST_VECTOR_STRING_SPLIT_ALLOW_EMPTY = 0x02,
};
 
/*!
 * \brief Append a string vector by splitting a string.
 *
 * \param dest Pointer to an initialized vector.
 * \param input String buffer to split.
 * \param delim String delimeter passed to strsep.
 * \param flags Processing options defined by \ref ast_vector_string_split_flags.
 * \param excludes_cmp NULL or a function like strcmp to exclude duplicate strings.
 *
 * \retval 0 Success
 * \retval -1 Failure
 *
 * \note All elements added to the vector are allocated.  The caller is always
 *       responsible for calling ast_free on each element in the vector even
 *       after failure.  It's possible for this function to successfully add
 *       some elements before failing.
 */
int ast_vector_string_split(struct ast_vector_string *dest,
    const char *input, const char *delim, int flags,
    int (*excludes_cmp)(const char *s1, const char *s2));
 
/*!
 * \brief Join the elements of a string vector into a single string.
 *
 * \param vec Pointer to the vector.
 * \param delim String to separate elements with.
 *
 * \retval Resulting string.  Must be freed with ast_free.
 *
 */
char *ast_vector_string_join(struct ast_vector_string *vec, const char *delim);
 
/*!
 * \brief Define a vector structure with a read/write lock
 *
 * \param name Optional vector struct name.
 * \param type Vector element type.
 */
#define AST_VECTOR_RW(name, type) \
    struct name {            \
        type *elems;         \
        size_t max;          \
        size_t current;      \
        ast_rwlock_t lock;   \
    }
 
/*!
 * \brief Initialize a vector
 *
 * If \a size is 0, then no space will be allocated until the vector is
 * appended to.
 *
 * \param vec Vector to initialize.
 * \param size Initial size of the vector.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 */
#define AST_VECTOR_INIT(vec, size) ({                   \
    size_t __size = (size);                     \
    size_t alloc_size = __size * sizeof(*((vec)->elems));       \
    (vec)->elems = alloc_size ? ast_calloc(1, alloc_size) : NULL;   \
    (vec)->current = 0;                     \
    if ((vec)->elems) {                     \
        (vec)->max = __size;                    \
    } else {                            \
        (vec)->max = 0;                     \
    }                               \
    (alloc_size == 0 || (vec)->elems != NULL) ? 0 : -1;     \
})
 
/*!
 * \brief Steal the elements from a vector and reinitialize.
 *
 * \param vec Vector to operate on.
 *
 * This allows you to use vector.h to construct a list and use the
 * data as a bare array.
 *
 * \note The stolen array must eventually be released using ast_free.
 *
 * \warning AST_VECTOR_SIZE and AST_VECTOR_MAX_SIZE are both reset
 *          to 0.  If either are needed they must be saved to a local
 *          variable before stealing the elements.
 */
#define AST_VECTOR_STEAL_ELEMENTS(vec) ({ \
    typeof((vec)->elems) __elems = (vec)->elems; \
    AST_VECTOR_INIT((vec), 0); \
    (__elems); \
})
 
/*!
 * \brief Initialize a vector with a read/write lock
 *
 * If \a size is 0, then no space will be allocated until the vector is
 * appended to.
 *
 * \param vec Vector to initialize.
 * \param size Initial size of the vector.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 */
#define AST_VECTOR_RW_INIT(vec, size) ({ \
    int res = -1; \
    if (AST_VECTOR_INIT(vec, size) == 0) { \
        res = ast_rwlock_init(&(vec)->lock); \
    } \
    res; \
})
 
/*!
 * \brief Deallocates this vector.
 *
 * If any code to free the elements of this vector needs to be run, that should
 * be done prior to this call.
 *
 * \param vec Vector to deallocate.
 */
#define AST_VECTOR_FREE(vec) do {       \
    ast_free((vec)->elems);         \
    (vec)->elems = NULL;            \
    (vec)->max = 0;             \
    (vec)->current = 0;         \
} while (0)
 
/*!
 * \brief Deallocates this vector pointer.
 *
 * If any code to free the elements of this vector need to be run, that should
 * be done prior to this call.
 *
 * \param vec Pointer to a malloc'd vector structure.
 */
#define AST_VECTOR_PTR_FREE(vec) do { \
    AST_VECTOR_FREE(vec); \
    ast_free(vec); \
} while (0)
 
/*!
 * \brief Deallocates this locked vector
 *
 * If any code to free the elements of this vector need to be run, that should
 * be done prior to this call.
 *
 * \param vec Vector to deallocate.
 */
#define AST_VECTOR_RW_FREE(vec) do { \
    AST_VECTOR_FREE(vec); \
    ast_rwlock_destroy(&(vec)->lock); \
} while(0)
 
/*!
 * \brief Deallocates this locked vector pointer.
 *
 * If any code to free the elements of this vector need to be run, that should
 * be done prior to this call.
 *
 * \param vec Pointer to a malloc'd vector structure.
 */
#define AST_VECTOR_RW_PTR_FREE(vec) do { \
    AST_VECTOR_RW_FREE(vec); \
    ast_free(vec); \
} while(0)
 
/*!
 * \internal
 */
#define __make_room(idx, vec) ({ \
    int res = 0;                                \
    do {                                                        \
        if ((idx) >= (vec)->max) {                              \
            size_t new_max = ((idx) + 1) * 2;               \
            typeof((vec)->elems) new_elems = ast_calloc(1,      \
                new_max * sizeof(*new_elems));                  \
            if (new_elems) {                                    \
                if ((vec)->elems) {                             \
                    memcpy(new_elems, (vec)->elems,             \
                        (vec)->current * sizeof(*new_elems));   \
                    ast_free((vec)->elems);                     \
                }                                               \
                (vec)->elems = new_elems;                       \
                (vec)->max = new_max;                           \
            } else {                                            \
                res = -1;                                       \
                break;                                          \
            }                                                   \
        }                                                       \
    } while(0);                                                 \
    res;                                                        \
})
 
/*!
 * \brief Append an element to a vector, growing the vector if needed.
 *
 * \param vec Vector to append to.
 * \param elem Element to append.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 */
#define AST_VECTOR_APPEND(vec, elem) ({                     \
    int res = 0;                                            \
    do {                                                    \
        if (__make_room((vec)->current, vec) != 0) {        \
            res = -1;                                       \
            break;                                          \
        }                                                   \
        (vec)->elems[(vec)->current++] = (elem);            \
    } while (0);                                            \
    res;                                                    \
})
 
/*!
 * \brief Replace an element at a specific position in a vector, growing the vector if needed.
 *
 * \param vec Vector to replace into.
 * \param idx Position to replace.
 * \param elem Element to replace.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 *
 * \warning This macro will overwrite anything already present at the position provided.
 *
 * \warning Use of this macro with the expectation that the element will remain at the provided
 * index means you can not use the UNORDERED assortment of macros. These macros alter the ordering
 * of the vector itself.
 */
#define AST_VECTOR_REPLACE(vec, idx, elem) ({       \
    int res = 0;                                    \
    do {                                            \
        if (__make_room((idx), vec) != 0) {         \
            res = -1;                               \
            break;                                  \
        }                                           \
        (vec)->elems[(idx)] = (elem);               \
        if (((idx) + 1) > (vec)->current) {         \
            (vec)->current = (idx) + 1;             \
        }                                           \
    } while(0);                                     \
    res;                                            \
})
 
/*!
 * \brief Default a vector up to size with the given value.
 *
 * \note If a size of 0 is given then all elements in the given vector are set.
 * \note The vector will grow to the given size if needed.
 *
 * \param vec Vector to default.
 * \param size The number of elements to default
 * \param value The default value to set each element to
 */
#define AST_VECTOR_DEFAULT(vec, size, value) ({ \
    int res = 0;                            \
    typeof((size)) __size = (size) ? (size) : AST_VECTOR_SIZE(vec); \
    size_t idx;                         \
    for (idx = 0; idx < __size; ++idx) {                \
        res = AST_VECTOR_REPLACE(vec, idx, value);      \
        if (res == -1) {                    \
            break;                      \
        }                           \
    }                               \
    res;                                \
})
 
/*!
 * \brief Insert an element at a specific position in a vector, growing the vector if needed.
 *
 * \param vec Vector to insert into.
 * \param idx Position to insert at.
 * \param elem Element to insert.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 *
 * \warning This macro will shift existing elements right to make room for the new element.
 *
 * \warning Use of this macro with the expectation that the element will remain at the provided
 * index means you can not use the UNORDERED assortment of macros. These macros alter the ordering
 * of the vector itself.
 */
#define AST_VECTOR_INSERT_AT(vec, idx, elem) ({ \
    int res = 0; \
    size_t __move; \
    do { \
        if (__make_room(((idx) > (vec)->current ? (idx) : (vec)->current), vec) != 0) {                         \
            res = -1;                                       \
            break;                                          \
        }                                                       \
        if ((vec)->current > 0 && (idx) < (vec)->current) { \
            __move = ((vec)->current - (idx)) * sizeof(typeof((vec)->elems[0])); \
            memmove(&(vec)->elems[(idx) + 1], &(vec)->elems[(idx)], __move); \
        } \
        (vec)->elems[(idx)] = (elem); \
        (vec)->current = ((idx) > (vec)->current ? (idx) : (vec)->current) + 1; \
    } while (0); \
    res; \
})
 
/*!
 * \brief Add an element into a sorted vector
 *
 * \param vec Sorted vector to add to.
 * \param elem Element to insert. Must not be an array type.
 * \param cmp A strcmp compatible compare function.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 *
 * \warning Use of this macro on an unsorted vector will produce unpredictable results
 * \warning 'elem' must not be an array type so passing 'x' where 'x' is defined as
 *          'char x[4]' will fail to compile. However casting 'x' as 'char *' does
 *          result in a value that CAN be used.
 */
#define AST_VECTOR_ADD_SORTED(vec, elem, cmp) ({ \
    int res = 0; \
    size_t __idx = (vec)->current; \
    typeof(elem) __elem = (elem); \
    do { \
        if (__make_room((vec)->current, vec) != 0) { \
            res = -1; \
            break; \
        } \
        while (__idx > 0 && (cmp((vec)->elems[__idx - 1], __elem) > 0)) { \
            (vec)->elems[__idx] = (vec)->elems[__idx - 1]; \
            __idx--; \
        } \
        (vec)->elems[__idx] = __elem; \
        (vec)->current++; \
    } while (0); \
    res; \
})
 
/*!
 * \brief Sort a vector in-place
 *
 * \param vec Vector to sort
 * \param cmp A memcmp compatible compare function
 */
#define AST_VECTOR_SORT(vec, cmp) ({ \
    qsort((vec)->elems, (vec)->current, sizeof(typeof((vec)->elems[0])), cmp); \
})
 
/*!
 * \brief Remove an element from a vector by index.
 *
 * Note that elements in the vector may be reordered, so that the remove can
 * happen in constant time.
 *
 * \param vec Vector to remove from.
 * \param idx Index of the element to remove.
 * \param preserve_ordered Preserve the vector order.
 *
 * \return The element that was removed.
 */
#define AST_VECTOR_REMOVE(vec, idx, preserve_ordered) ({ \
    typeof((vec)->elems[0]) res; \
    size_t __idx = (idx); \
    ast_assert(__idx < (vec)->current); \
    res = (vec)->elems[__idx]; \
    if ((preserve_ordered)) { \
        size_t __move; \
        __move = ((vec)->current - (__idx) - 1) * sizeof(typeof((vec)->elems[0])); \
        memmove(&(vec)->elems[__idx], &(vec)->elems[__idx + 1], __move); \
        (vec)->current--; \
    } else { \
        (vec)->elems[__idx] = (vec)->elems[--(vec)->current];   \
    }; \
    res;                            \
})
 
/*!
 * \brief Remove an element from an unordered vector by index.
 *
 * Note that elements in the vector may be reordered, so that the remove can
 * happen in constant time.
 *
 * \param vec Vector to remove from.
 * \param idx Index of the element to remove.
 * \return The element that was removed.
 */
#define AST_VECTOR_REMOVE_UNORDERED(vec, idx) \
    AST_VECTOR_REMOVE(vec, idx, 0)
 
/*!
 * \brief Remove an element from a vector by index while maintaining order.
 *
 * \param vec Vector to remove from.
 * \param idx Index of the element to remove.
 * \return The element that was removed.
 */
#define AST_VECTOR_REMOVE_ORDERED(vec, idx) \
    AST_VECTOR_REMOVE(vec, idx, 1)
 
/*!
 * \brief Remove all elements from a vector that matches the given comparison
 *
 * \param vec Vector to remove from.
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 * \param cleanup How to cleanup a removed element macro/function.
 *
 * \return the number of deleted elements.
 */
#define AST_VECTOR_REMOVE_ALL_CMP_UNORDERED(vec, value, cmp, cleanup) ({    \
    int count = 0;                          \
    size_t idx;                         \
    typeof(value) __value = (value);                \
    for (idx = 0; idx < (vec)->current; ) {             \
        if (cmp((vec)->elems[idx], __value)) {          \
            cleanup((vec)->elems[idx]);         \
            AST_VECTOR_REMOVE_UNORDERED((vec), idx);    \
            ++count;                    \
        } else {                        \
            ++idx;                      \
        }                           \
    }                               \
    count;                              \
})
 
/*!
 * \brief Remove an element from a vector that matches the given comparison
 *
 * \param vec Vector to remove from.
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 * \param cleanup How to cleanup a removed element macro/function.
 *
 * \retval 0 if element was removed.
 * \retval Non-zero if element was not in the vector.
 */
#define AST_VECTOR_REMOVE_CMP_UNORDERED(vec, value, cmp, cleanup) ({    \
    int res = -1;                           \
    size_t idx;                         \
    typeof(value) __value = (value);                \
    for (idx = 0; idx < (vec)->current; ++idx) {            \
        if (cmp((vec)->elems[idx], __value)) {          \
            cleanup((vec)->elems[idx]);         \
            AST_VECTOR_REMOVE_UNORDERED((vec), idx);    \
            res = 0;                    \
            break;                      \
        }                           \
    }                               \
    res;                                \
})
 
/*!
 * \brief Remove all elements from a vector that matches the given comparison while maintaining order
 *
 * \param vec Vector to remove from.
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 * \param cleanup How to cleanup a removed element macro/function.
 *
 * \return the number of deleted elements.
 */
#define AST_VECTOR_REMOVE_ALL_CMP_ORDERED(vec, value, cmp, cleanup) ({  \
    int count = 0;                          \
    size_t idx;                         \
    typeof(value) __value = (value);                \
    for (idx = 0; idx < (vec)->current; ) {             \
        if (cmp((vec)->elems[idx], __value)) {          \
            cleanup((vec)->elems[idx]);         \
            AST_VECTOR_REMOVE_ORDERED((vec), idx);      \
            ++count;                    \
        } else {                        \
            ++idx;                      \
        }                           \
    }                               \
    count;                              \
})
 
/*!
 * \brief Remove an element from a vector that matches the given comparison while maintaining order
 *
 * \param vec Vector to remove from.
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 * \param cleanup How to cleanup a removed element macro/function.
 *
 * \retval 0 if element was removed.
 * \retval Non-zero if element was not in the vector.
 */
#define AST_VECTOR_REMOVE_CMP_ORDERED(vec, value, cmp, cleanup) ({  \
    int res = -1;                           \
    size_t idx;                         \
    typeof(value) __value = (value);                \
    for (idx = 0; idx < (vec)->current; ++idx) {            \
        if (cmp((vec)->elems[idx], __value)) {          \
            cleanup((vec)->elems[idx]);         \
            AST_VECTOR_REMOVE_ORDERED((vec), idx);      \
            res = 0;                    \
            break;                      \
        }                           \
    }                               \
    res;                                \
})
 
/*!
 * \brief Default comparator for AST_VECTOR_REMOVE_ELEM_UNORDERED()
 *
 * \param elem Element to compare against
 * \param value Value to compare with the vector element.
 *
 * \retval 0 if element does not match.
 * \retval Non-zero if element matches.
 */
#define AST_VECTOR_ELEM_DEFAULT_CMP(elem, value) ((elem) == (value))
 
/*!
 * \brief Vector element cleanup that does nothing.
 *
 * \param elem Element to cleanup
 */
#define AST_VECTOR_ELEM_CLEANUP_NOOP(elem)
 
/*!
 * \brief Remove an element from a vector.
 *
 * \param vec Vector to remove from.
 * \param elem Element to remove
 * \param cleanup How to cleanup a removed element macro/function.
 *
 * \retval 0 if element was removed.
 * \retval Non-zero if element was not in the vector.
 */
#define AST_VECTOR_REMOVE_ELEM_UNORDERED(vec, elem, cleanup) ({ \
    AST_VECTOR_REMOVE_CMP_UNORDERED((vec), (elem),      \
        AST_VECTOR_ELEM_DEFAULT_CMP, cleanup);      \
})
 
/*!
 * \brief Remove an element from a vector while maintaining order.
 *
 * \param vec Vector to remove from.
 * \param elem Element to remove
 * \param cleanup How to cleanup a removed element macro/function.
 *
 * \retval 0 if element was removed.
 * \retval Non-zero if element was not in the vector.
 */
#define AST_VECTOR_REMOVE_ELEM_ORDERED(vec, elem, cleanup) ({   \
    AST_VECTOR_REMOVE_CMP_ORDERED((vec), (elem),        \
        AST_VECTOR_ELEM_DEFAULT_CMP, cleanup);      \
})
 
/*!
 * \brief Get the number of elements in a vector.
 *
 * \param vec Vector to query.
 * \return Number of elements in the vector.
 */
#define AST_VECTOR_SIZE(vec) (vec)->current
 
/*!
 * \brief Get the maximum number of elements the vector can currently hold.
 *
 * \param vec Vector to query.
 * \return Maximum number of elements the vector can currently hold.
 */
#define AST_VECTOR_MAX_SIZE(vec) (vec)->max
 
/*!
 * \brief Reset vector.
 *
 * \param vec Vector to reset.
 * \param cleanup A cleanup callback or AST_VECTOR_ELEM_CLEANUP_NOOP.
 */
#define AST_VECTOR_RESET(vec, cleanup) ({ \
    AST_VECTOR_CALLBACK_VOID(vec, cleanup); \
    (vec)->current = 0; \
})
 
/*!
 * \brief Resize a vector so that its capacity is the same as its size.
 *
 * \param vec Vector to compact.
 *
 * \retval 0 on success.
 * \retval Non-zero on failure.
 */
#define AST_VECTOR_COMPACT(vec) ({                  \
    int res = 0;                            \
    do {                                \
        size_t new_max = (vec)->current;            \
        if (new_max == 0) {                 \
            ast_free((vec)->elems);             \
            (vec)->elems = NULL;                \
            (vec)->max = 0;                 \
        } else if ((vec)->max > new_max) {          \
            typeof((vec)->elems) new_elems = ast_realloc(   \
                (vec)->elems,               \
                new_max * sizeof(*new_elems));      \
            if (new_elems) {                \
                (vec)->elems = new_elems;       \
                (vec)->max = new_max;           \
            } else {                    \
                res = -1;               \
                break;                  \
            }                       \
        }                           \
    } while(0);                         \
    res;                                \
})
 
/*!
 * \brief Get an address of element in a vector.
 *
 * \param vec Vector to query.
 * \param idx Index of the element to get address of.
 */
#define AST_VECTOR_GET_ADDR(vec, idx) ({    \
    size_t __idx = (idx);           \
    ast_assert(__idx < (vec)->current); \
    &(vec)->elems[__idx];           \
})
 
/*!
 * \brief Get an element from a vector.
 *
 * \param vec Vector to query.
 * \param idx Index of the element to get.
 */
#define AST_VECTOR_GET(vec, idx) ({     \
    size_t __idx = (idx);           \
    ast_assert(__idx < (vec)->current); \
    (vec)->elems[__idx];            \
})
 
/*!
 * \brief Get the nth index from a vector that matches the given comparison
 *
 * \param vec Vector to get from.
 * \param nth The nth index to find
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 *
 * \return a pointer to the element that was found or NULL
 */
#define AST_VECTOR_GET_INDEX_NTH(vec, nth, value, cmp) ({ \
    int res = -1; \
    size_t idx; \
    typeof(nth) __nth = (nth); \
    typeof(value) __value = (value); \
    for (idx = 0; idx < (vec)->current; ++idx) { \
        if (cmp((vec)->elems[idx], __value) && !(--__nth)) {    \
            res = (int)idx;                 \
            break; \
        } \
    } \
    res; \
})
 
/*!
 * \brief Get the 1st index from a vector that matches the given comparison
 *
 * \param vec Vector to get from.
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 *
 * \return a pointer to the element that was found or NULL
 */
#define AST_VECTOR_GET_INDEX(vec, value, cmp) \
    AST_VECTOR_GET_INDEX_NTH(vec, 1, value, cmp)
 
/*!
 * \brief Get an element from a vector that matches the given comparison
 *
 * \param vec Vector to get from.
 * \param value Value to pass into comparator.
 * \param cmp Comparator function/macros (called as \c cmp(elem, value))
 *
 * \return a pointer to the element that was found or NULL
 */
#define AST_VECTOR_GET_CMP(vec, value, cmp) ({ \
    void *res = NULL; \
    size_t idx; \
    typeof(value) __value = (value); \
    for (idx = 0; idx < (vec)->current; ++idx) { \
        if (cmp((vec)->elems[idx], __value)) { \
            res = &(vec)->elems[idx]; \
            break; \
        } \
    } \
    res; \
})
 
/*!
 * \brief Default callback for AST_VECTOR_CALLBACK()
 *
 * \param element Element to compare against
 *
 * \retval CMP_MATCH always.
 */
#define AST_VECTOR_MATCH_ALL(element) (CMP_MATCH)
 
 
/*!
 * \brief Execute a callback on every element in a vector returning the first matched
 *
 * \param vec Vector to operate on.
 * \param callback A callback that takes at least 1 argument (the element)
 * plus number of optional arguments
 * \param default_value A default value to return if no elements matched
 *
 * \return the first element matched before CMP_STOP was returned
 * or the end of the vector was reached. Otherwise, default_value
 */
#define AST_VECTOR_CALLBACK(vec, callback, default_value, ...) ({ \
    size_t idx; \
    typeof((vec)->elems[0]) res = default_value;                \
    for (idx = 0; idx < (vec)->current; idx++) { \
        int rc = callback((vec)->elems[idx], ##__VA_ARGS__);    \
        if (rc & CMP_MATCH) { \
            res = (vec)->elems[idx]; \
            break; \
        }\
        if (rc & CMP_STOP) { \
            break; \
        }\
    } \
    res; \
})
 
/*!
 * \brief Execute a callback on every element in a vector returning the matching
 * elements in a new vector
 *
 * This macro basically provides a filtered clone.
 *
 * \param vec Vector to operate on.
 * \param callback A callback that takes at least 1 argument (the element)
 * plus number of optional arguments
 *
 * \return a vector containing the elements matched before CMP_STOP was returned
 * or the end of the vector was reached. The vector may be empty and could be NULL
 * if there was not enough memory to allocate it's control structure.
 *
 * \warning The returned vector must have AST_VECTOR_PTR_FREE()
 * called on it after you've finished with it.
 *
 * \note The type of the returned vector must be traceable to the original vector.
 *
 * The following will result in "error: assignment from incompatible pointer type"
 * because these declare 2 different structures.
 *
 * \code
 * AST_VECTOR(, char *) vector_1;
 * AST_VECTOR(, char *) *vector_2;
 *
 * vector_2 = AST_VECTOR_CALLBACK_MULTIPLE(&vector_1, callback);
 * \endcode
 *
 * This will work because you're using the type of the first
 * to declare the second:
 *
 * \code
 * AST_VECTOR(mytype, char *) vector_1;
 * struct mytype *vector_2 = NULL;
 *
 * vector_2 = AST_VECTOR_CALLBACK_MULTIPLE(&vector_1, callback);
 * \endcode
 *
 * This will also work because you're declaring both vector_1 and
 * vector_2 from the same definition.
 *
 * \code
 * AST_VECTOR(, char *) vector_1, *vector_2 = NULL;
 *
 * vector_2 = AST_VECTOR_CALLBACK_MULTIPLE(&vector_1, callback);
 * \endcode
 */
#define AST_VECTOR_CALLBACK_MULTIPLE(vec, callback, ...) ({ \
    size_t idx; \
    typeof((vec)) new_vec; \
    do { \
        new_vec = ast_malloc(sizeof(*new_vec)); \
        if (!new_vec) { \
            break; \
        } \
        if (AST_VECTOR_INIT(new_vec, AST_VECTOR_SIZE((vec))) != 0) { \
            ast_free(new_vec); \
            new_vec = NULL; \
            break; \
        } \
        for (idx = 0; idx < (vec)->current; idx++) { \
            int rc = callback((vec)->elems[idx], ##__VA_ARGS__);    \
            if (rc & CMP_MATCH) { \
                AST_VECTOR_APPEND(new_vec, (vec)->elems[idx]); \
            } \
            if (rc & CMP_STOP) { \
                break; \
            }\
        } \
    } while(0); \
    new_vec; \
})
 
/*!
 * \brief Execute a callback on every element in a vector disregarding callback return
 *
 * \param vec Vector to operate on.
 * \param callback A callback that takes at least 1 argument (the element)
 * plus number of optional arguments
 */
#define AST_VECTOR_CALLBACK_VOID(vec, callback, ...) ({ \
    size_t idx; \
    for (idx = 0; idx < (vec)->current; idx++) { \
        callback((vec)->elems[idx], ##__VA_ARGS__); \
    } \
})
 
/*!
 * \brief Obtain read lock on vector
 *
 * \param vec Vector to operate on.
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_RDLOCK(vec) ast_rwlock_rdlock(&(vec)->lock)
 
/*!
 * \brief Obtain write lock on vector
 *
 * \param vec Vector to operate on.
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_WRLOCK(vec) ast_rwlock_wrlock(&(vec)->lock)
 
/*!
 * \brief Unlock vector
 *
 * \param vec Vector to operate on.
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_UNLOCK(vec) ast_rwlock_unlock(&(vec)->lock)
 
/*!
 * \brief Try to obtain read lock on vector failing immediately if unable
 *
 * \param vec Vector to operate on.
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_RDLOCK_TRY(vec) ast_rwlock_tryrdlock(&(vec)->lock)
 
/*!
 * \brief Try to obtain write lock on vector failing immediately if unable
 *
 * \param vec Vector to operate on.
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_WRLOCK_TRY(vec) ast_rwlock_trywrlock(&(vec)->lock)
 
/*!
 * \brief Try to obtain read lock on vector failing after timeout if unable
 *
 * \param vec Vector to operate on.
 * \param timespec
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_RDLOCK_TIMED(vec, timespec) ast_rwlock_timedrdlock(&(vec)->lock, timespec)
 
/*!
 * \brief Try to obtain write lock on vector failing after timeout if unable
 *
 * \param vec Vector to operate on.
 * \param timespec
 *
 * \retval 0 if success
 * \retval Non-zero if error
 */
#define AST_VECTOR_RW_WRLOCK_TIMED(vec, timespec) ast_rwlock_timedwrlock(&(vec)->lock, timespec)
 
#endif /* _ASTERISK_VECTOR_H */