apr_tables.h

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

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#ifndef APR_TABLES_H
#define APR_TABLES_H

#include "apr.h"
#include "apr_pools.h"

#if APR_HAVE_STDARG_H
#include <stdarg.h>     /* for va_list */
#endif

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/*
 * Define the structures used by the APR general-purpose library.
 */

/**
 * @package APR Table library
 */

/*
 * Memory allocation stuff, like pools, arrays, and tables.  Pools
 * and tables are opaque structures to applications, but arrays are
 * published.
 */
typedef struct apr_table_t apr_table_t;
typedef struct apr_array_header_t apr_array_header_t;

/** An opaque array type */
struct apr_array_header_t {
    /** The pool the array is allocated out of */
    apr_pool_t *cont;
    /** The amount of memory allocated for each element of the array */
    int elt_size;
    /** The number of active elements in the array */
    int nelts;
    /** The number of elements allocated in the array */
    int nalloc;
    /** The elements in the array */
    char *elts;
};

/** 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 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
};

/**
 * The (opaque) structure for string-content tables.
 */
typedef struct apr_table_entry_t apr_table_entry_t;

/** The type for each entry in a string-content table */
struct apr_table_entry_t {
    /** The key for the current table entry */
    char *key;          /* maybe NULL in future;
                         * check when iterating thru table_elts
                         */
    /** The value for the current table entry */
    char *val;
};

/**
 * Get the elements from a table
 * @param t The table
 * @return An array containing the contents of the table
 * @deffunc apr_array_header_t *apr_table_elts(apr_table_t *t)
 */
#define apr_table_elts(t) ((apr_array_header_t *)(t))

/**
 * Determine if the table is empty
 * @param t The table to check
 * @return True if empty, Falso otherwise
 * @deffunc int apr_is_empty_table(apr_table_t *t)
 */
#define apr_is_empty_table(t) (((t) == NULL) \
                               || (((apr_array_header_t *)(t))->nelts == 0))

/**
 * Create an array
 * @param p The pool to allocate the memory out of
 * @param nelts the number of elements in the initial array
 * @param elt_size The size of each element in the array.
 * @return The new array
 * @deffunc apr_array_header_t *apr_array_make(struct apr_pool_t *p, int nelts, int elt_size)
 */
APR_DECLARE(apr_array_header_t *) apr_array_make(struct apr_pool_t *p,
                                                 int nelts, int elt_size);

/**
 * Add a new element to an array
 * @param arr The array to add an element to.
 * @return Location for the new element in the array.
 * @tip If there are no free spots in the array, then this function will
 *      allocate new space for the new element.
 * @deffunc void *apr_array_push(apr_array_header_t *arr)
 */
APR_DECLARE(void *) apr_array_push(apr_array_header_t *arr);

/**
 * Concatenate two arrays together
 * @param dst The destination array, and the one to go first in the combined 
 *            array
 * @param src The source array to add to the destination array
 * @deffunc void apr_array_cat(apr_array_header_t *dst, const apr_array_header_t *src)
 */
APR_DECLARE(void) apr_array_cat(apr_array_header_t *dst,
			        const apr_array_header_t *src);

/**
 * Copy the entire array
 * @param p The pool to allocate the copy of the array out of
 * @param arr The array to copy
 * @return An exact copy of the array passed in
 * @deffunc apr_array_header_t *apr_array_copy(apr_pool_t *p, const apr_array_header_t *arr)
 * @tip The alternate apr_array_copy_hdr copies only the header, and arranges 
 * for the elements to be copied if (and only if) the code subsequently does 
 * a push or arraycat.
 */
APR_DECLARE(apr_array_header_t *) apr_array_copy(struct apr_pool_t *p,
                                      const apr_array_header_t *arr);
/**
 * Copy the headers of the array, and arrange for the elements to be copied if
 * and only if the code subsequently does a push or arraycat.
 * @param p The pool to allocate the copy of the array out of
 * @param arr The array to copy
 * @return An exact copy of the array passed in
 * @deffunc apr_array_header_t *apr_array_copy_hdr(apr_pool_t *p, const apr_array_header_t *arr)
 * @tip The alternate apr_array_copy copies the *entire* array.
 */
APR_DECLARE(apr_array_header_t *) apr_array_copy_hdr(struct apr_pool_t *p,
                                      const apr_array_header_t *arr);

/**
 * Append one array to the end of another, creating a new array in the process.
 * @param p The pool to allocate the new array out of
 * @param first The array to put first in the new array.
 * @param second The array to put second in the new array.
 * @param return A new array containing the data from the two arrays passed in.
 * @deffunc apr_array_header_t *apr_array_append(apr_pool_t *p, const apr_array_header_t *first, const apr_array_header_t *second)
*/
APR_DECLARE(apr_array_header_t *) apr_array_append(struct apr_pool_t *p,
                                      const apr_array_header_t *first,
                                      const apr_array_header_t *second);

/**
 * 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.
 * @param p The pool to allocate the string out of
 * @param arr The array to generate the string from
 * @param sep The separator to use