freeswitch/src/include/switch_xml.h

/* switch_xml.h
 *
 * Copyright 2004, 2005 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 _SWITCH_XML_H
#define _SWITCH_XML_H

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

BEGIN_EXTERN_C

#define SWITCH_XML_BUFSIZE 1024 // size of internal memory buffers

#define SWITCH_XML_NAMEM   0x80 // name is malloced
#define SWITCH_XML_TXTM    0x40 // txt is malloced
#define SWITCH_XML_DUP     0x20 // attribute name and value are strduped

typedef struct switch_xml *switch_xml_t;
struct switch_xml {
    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
    switch_xml_t next;    // next tag with same name in this section at this depth
    switch_xml_t sibling; // next tag with different name in same section and depth
    switch_xml_t ordered; // next tag, same section and depth, in original order
    switch_xml_t child;   // head of sub tag list, NULL if none
    switch_xml_t parent;  // parent tag, NULL if current tag is root tag
    short flags;     // additional information
};

// Given a string of xml data and its length, parses it and creates an switch_xml
// 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.
switch_xml_t switch_xml_parse_str(char *s, size_t len);

// A wrapper for switch_xml_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.
switch_xml_t switch_xml_parse_fd(int fd);

// a wrapper for switch_xml_parse_fd() that accepts a file name
switch_xml_t switch_xml_parse_file(const char *file);
    
// Wrapper for switch_xml_parse_str() that accepts a file stream. Reads the entire
// stream into memory and then parses it. For xml files, use switch_xml_parse_file()
// or switch_xml_parse_fd()
switch_xml_t switch_xml_parse_fp(FILE *fp);

// returns the first child tag (one level deeper) with the given name or NULL
// if not found
switch_xml_t switch_xml_child(switch_xml_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 switch_xml_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.
switch_xml_t switch_xml_idx(switch_xml_t xml, int idx);

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

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

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

// Traverses the switch_xml 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 = switch_xml_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.
switch_xml_t switch_xml_get(switch_xml_t xml, ...);

// Converts an switch_xml structure back to xml. Returns a string of xml data that
// must be freed.
char *switch_xml_toxml(switch_xml_t xml);

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

// frees the memory allocated for an switch_xml structure
void switch_xml_free(switch_xml_t xml);
    
// returns parser error message or empty string if none
const char *switch_xml_error(switch_xml_t xml);

// returns a new empty switch_xml structure with the given root tag name
switch_xml_t switch_xml_new(const char *name);

// wrapper for switch_xml_new() that strdup()s name
#define switch_xml_new_d(name) switch_xml_set_flag(switch_xml_new(strdup(name)), SWITCH_XML_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.
switch_xml_t switch_xml_add_child(switch_xml_t xml, const char *name, size_t off);

// wrapper for switch_xml_add_child() that strdup()s name
#define switch_xml_add_child_d(xml, name, off) \
    switch_xml_set_flag(switch_xml_add_child(xml, strdup(name), off), SWITCH_XML_NAMEM)

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

// wrapper for switch_xml_set_txt() that strdup()s txt
#define switch_xml_set_txt_d(xml, txt) \
    switch_xml_set_flag(switch_xml_set_txt(xml, strdup(txt)), SWITCH_XML_TXTM)

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

// Wrapper for switch_xml_set_attr() that strdup()s name/value. Value cannot be NULL
#define switch_xml_set_attr_d(xml, name, value) \
    switch_xml_set_attr(switch_xml_set_flag(xml, SWITCH_XML_DUP), strdup(name), strdup(value))

// sets a flag for the given tag and returns the tag
switch_xml_t switch_xml_set_flag(switch_xml_t xml, short flag);

// removes a tag along with all its subtags
void switch_xml_remove(switch_xml_t xml);

END_EXTERN_C


#endif // _SWITCH_XML_H