libvpr/include/ezxml.h

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/** 
 * @file ezxml.h
 *
 * Copyright 2004-2006 Aaron Voisine <aaron@voisine.org>
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef _EZXML_H
#define _EZXML_H

#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <fcntl.h>

#ifdef __cplusplus
extern "C"
{
#endif

#define EZXML_BUFSIZE 1024      /**< size of internal memory buffers */
#define EZXML_NAMEM   0x80      /**< name is malloced */
#define EZXML_TXTM    0x40      /**< txt is malloced */
#define EZXML_DUP     0x20      /**< attribute name and value are strduped */
#define EZXML_ERRL 128          /**< maximum error string length */

    typedef struct ezxml *ezxml_t;
    struct ezxml
    {
        char *name;             /**< tag name */
        char **attr;            /**< tag attributes { name, value, name, value, ... NULL } */
        char *txt;              /**< tag character content, empty string if none */
        size_t off;             /**< tag offset from start of parent tag character content */
        ezxml_t next;           /**< next tag with same name in this section at this depth */
        ezxml_t sibling;        /**< next tag with different name in same section and depth */
        ezxml_t ordered;        /**< next tag, same section and depth, in original order */
        ezxml_t child;          /**< head of sub tag list, NULL if none */
        ezxml_t parent;         /**< parent tag, NULL if current tag is root tag */
        short flags;            /**< additional information */
        /* Jason Luu June 22, 2010, Added line number support */
        int line;
    };

        /* Jason Luu June 22, 2010, Moved root definition to header */
        /** additional data for the root tag */
        typedef struct ezxml_root *ezxml_root_t;
        struct ezxml_root
        {                               
                struct ezxml xml;               /**< is a super-struct built on top of ezxml struct */
                ezxml_t cur;            /**< current xml tree insertion point */
                char *m;                        /**< original xml string */
                size_t len;                     /**< length of allocated memory for mmap, -1 for malloc */
                char *u;                        /**< UTF-8 conversion of string if original was UTF-16 */
                char *s;                        /**< start of work area */
                char *e;                        /**< end of work area */
                char **ent;                     /**< general entities (ampersand sequences) */
                char ***attr;           /**< default attributes */
                char ***pi;                     /**< processing instructions */
                short standalone;               /**< non-zero if <?xml standalone="yes"?> */
                char err[EZXML_ERRL];   /**< error string */
        };


/** Given a string of xml data and its length, parses it and creates an ezxml 
 * structure. For efficiency, modifies the data by adding null terminators 
 * and decoding ampersand sequences. If you don't want this, copy the data and 
 * pass in the copy. Returns NULL on failure. 
 */
    ezxml_t ezxml_parse_str(char *s,
                            size_t len);

/** A wrapper for ezxml_parse_str() that accepts a file descriptor. First 
 * attempts to mem map the file. Failing that, reads the file into memory. 
 * Returns NULL on failure. 
 */
    ezxml_t ezxml_parse_fd(int fd);

/** a wrapper for ezxml_parse_fd() that accepts a file name */
    ezxml_t ezxml_parse_file(const char *file);

/** Wrapper for ezxml_parse_str() that accepts a file stream. Reads the entire 
 * stream into memory and then parses it. For xml files, use ezxml_parse_file()
 * or ezxml_parse_fd() 
 */
    ezxml_t ezxml_parse_fp(FILE * fp);

/** returns the first child tag (one level deeper) with the given name or NULL 
 * if not found 
 */
    ezxml_t ezxml_child(ezxml_t xml,
                        const char *name);

/** returns the next tag of the same name in the same section and depth or NULL 
 * if not found 
 */
#define ezxml_next(xml) ((xml) ? xml->next : NULL)

/** Returns the Nth tag with the same name in the same section at the same depth 
 * or NULL if not found. An index of 0 returns the tag given. 
 */
    ezxml_t ezxml_idx(ezxml_t xml,
                      int idx);

/** returns the name of the given tag */
#define ezxml_name(xml) ((xml) ? xml->name : NULL)

/** returns the given tag's character content or empty string if none */
#define ezxml_txt(xml) ((xml) ? xml->txt : "")

/** returns the value of the requested tag attribute, or NULL if not found */
    const char *ezxml_attr(ezxml_t xml,
                           const char *attr);

/** Traverses the ezxml sturcture to retrieve a specific subtag. Takes a 
* variable length list of tag names and indexes. The argument list must be 
* terminated by either an index of -1 or an empty string tag name. Example:  
* title = ezxml_get(library, "shelf", 0, "book", 2, "title", -1); 
* This retrieves the title of the 3rd book on the 1st shelf of library. 
* Returns NULL if not found. 
*/
    ezxml_t ezxml_get(ezxml_t xml,
                      ...);

/** Converts an ezxml structure back to xml. Returns a string of xml data that 
 * must be freed. 
 */
    char *ezxml_toxml(ezxml_t xml);

/** returns a NULL terminated array of processing instructions for the given 
 * target 
 */
    const char **ezxml_pi(ezxml_t xml,
                          const char *target);

/** frees the memory allocated for an ezxml structure */
    void ezxml_free(ezxml_t xml);

/** returns parser error message or empty string if none */
    const char *ezxml_error(ezxml_t xml);

/** returns a new empty ezxml structure with the given root tag name */
    ezxml_t ezxml_new(const char *name);

/** wrapper for ezxml_new() that strdup()s name */
#define ezxml_new_d(name) ezxml_set_flag(ezxml_new(strdup(name)), EZXML_NAMEM)

/** Adds a child tag. off is the offset of the child tag relative to the start 
 * of the parent tag's character content. Returns the child tag. 
 */
        ezxml_t ezxml_add_child(
                                ezxml_t xml,
                            const char *name,
                            size_t off);

/** wrapper for ezxml_add_child() that strdup()s name */
#define ezxml_add_child_d(xml, name, off) \
    ezxml_set_flag(ezxml_add_child(xml, strdup(name), off), EZXML_NAMEM)

/** sets the character content for the given tag and returns the tag */
    ezxml_t ezxml_set_txt(ezxml_t xml,
                          const char *txt);

/** wrapper for ezxml_set_txt() that strdup()s txt */
#define ezxml_set_txt_d(xml, txt) \
    ezxml_set_flag(ezxml_set_txt(xml, strdup(txt)), EZXML_TXTM)

/** Sets the given tag attribute or adds a new attribute if not found. A value 
 * of NULL will remove the specified attribute. Returns the tag given. 
 */
    ezxml_t ezxml_set_attr(ezxml_t xml,
                           const char *name,
                           const char *value);

/** Wrapper for ezxml_set_attr() that strdup()s name/value. Value cannot be NULL */
#define ezxml_set_attr_d(xml, name, value) \
    ezxml_set_attr(ezxml_set_flag(xml, EZXML_DUP), strdup(name), strdup(value))

/** sets a flag for the given tag and returns the tag */
    ezxml_t ezxml_set_flag(ezxml_t xml,
                           short flag);

/** removes a tag along with its subtags without freeing its memory */
    ezxml_t ezxml_cut(ezxml_t xml);

/** inserts an existing tag into an ezxml structure */
    ezxml_t ezxml_insert(ezxml_t xml,
                         ezxml_t dest,
                         size_t off);

/** Moves an existing tag to become a subtag of dest at the given offset from 
 * the start of dest's character content. Returns the moved tag. 
 */
#define ezxml_move(xml, dest, off) ezxml_insert(ezxml_cut(xml), dest, off)

/** removes a tag along with all its subtags */
#define ezxml_remove(xml) ezxml_free(ezxml_cut(xml))

#ifdef __cplusplus
}
#endif
#endif                          /* _EZXML_H */