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/* Helper routines for parsing XML using Expat.
Copyright (C) 2006-2021 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <>. */
#include "gdb_obstack.h"
#include "gdbsupport/xml-utils.h"
#include "gdbsupport/byte-vector.h"
#include "gdbsupport/gdb_optional.h"
#include "gdbsupport/function-view.h"
struct gdb_xml_parser;
struct gdb_xml_element;
struct gdb_xml_attribute;
/* Return an XML document which was compiled into GDB, from
the given FILENAME, or NULL if the file was not compiled in. */
const char *fetch_xml_builtin (const char *filename);
/* A to_xfer_partial helper function which reads XML files which were
compiled into GDB. The target may call this function from its own
to_xfer_partial handler, after converting object and annex to the
appropriate filename. */
LONGEST xml_builtin_xfer_partial (const char *filename,
gdb_byte *readbuf, const gdb_byte *writebuf,
ULONGEST offset, LONGEST len);
/* Support for XInclude. */
/* Callback to fetch a new XML file, based on the provided HREF. */
using xml_fetch_another = gdb::function_view<gdb::optional<gdb::char_vector>
(const char * /* href */)>;
/* Append the expansion of TEXT after processing <xi:include> tags in
RESULT. FETCHER will be called to retrieve any new files. DEPTH
should be zero on the initial call.
On failure, this function uses NAME in a warning and returns false.
It may throw an exception, but does not for XML parsing
problems. */
bool xml_process_xincludes (std::string &result,
const char *name, const char *text,
xml_fetch_another fetcher, int depth);
/* Simplified XML parser infrastructure. */
/* A name and value pair, used to record parsed attributes. */
struct gdb_xml_value
gdb_xml_value (const char *name_, void *value_)
: name (name_), value (value_)
const char *name;
gdb::unique_xmalloc_ptr<void> value;
/* The type of an attribute handler.
PARSER is the current XML parser, which should be used to issue any
debugging or error messages. The second argument is the
corresponding attribute description, so that a single handler can
be used for multiple attributes; the attribute name is available
for error messages and the handler data is available for additional
customization (see gdb_xml_parse_attr_enum). VALUE is the string
value of the attribute.
The returned value should be freeable with xfree, and will be freed
after the start handler is called. Errors should be reported by
calling gdb_xml_error. */
typedef void *(gdb_xml_attribute_handler) (struct gdb_xml_parser *parser,
const struct gdb_xml_attribute *,
const char *value);
/* Flags for attributes. If no flags are specified, the attribute is
required. */
enum gdb_xml_attribute_flag
GDB_XML_AF_OPTIONAL = 1 << 0, /* The attribute is optional. */
/* An expected attribute and the handler to call when it is
encountered. Arrays of struct gdb_xml_attribute are terminated
by an entry with NAME == NULL. */
struct gdb_xml_attribute
const char *name;
int flags;
gdb_xml_attribute_handler *handler;
const void *handler_data;
/* Flags for elements. If no flags are specified, the element is
required exactly once. */
enum gdb_xml_element_flag
GDB_XML_EF_OPTIONAL = 1 << 0, /* The element is optional. */
GDB_XML_EF_REPEATABLE = 1 << 1, /* The element is repeatable. */
/* A handler called at the beginning of an element.
PARSER is the current XML parser, which should be used to issue any
debugging or error messages. ELEMENT is the current element.
USER_DATA is the opaque pointer supplied when the parser was
created. ATTRIBUTES is a vector of the values of any attributes
attached to this element.
The start handler will only be called if all the required
attributes were present and parsed successfully, and elements of
ATTRIBUTES are guaranteed to be in the same order used in
ELEMENT->ATTRIBUTES (not the order from the XML file). Accordingly
fixed offsets can be used to find any non-optional attributes as
long as no optional attributes precede them. */
typedef void (gdb_xml_element_start_handler)
(struct gdb_xml_parser *parser, const struct gdb_xml_element *element,
void *user_data, std::vector<gdb_xml_value> &attributes);
/* A handler called at the end of an element.
PARSER, ELEMENT, and USER_DATA are as for the start handler. BODY
is any accumulated body text inside the element, with leading and
trailing whitespace removed. It will never be NULL. */
typedef void (gdb_xml_element_end_handler)
(struct gdb_xml_parser *, const struct gdb_xml_element *,
void *user_data, const char *body_text);
/* An expected element and the handlers to call when it is
encountered. Arrays of struct gdb_xml_element are terminated
by an entry with NAME == NULL. */
struct gdb_xml_element
const char *name;
const struct gdb_xml_attribute *attributes;
const struct gdb_xml_element *children;
int flags;
gdb_xml_element_start_handler *start_handler;
gdb_xml_element_end_handler *end_handler;
/* Parse a XML document. DOCUMENT is the data to parse, which should
be NUL-terminated. If non-NULL, use the compiled-in DTD named
DTD_NAME to drive the parsing.
The return value is 0 for success or -1 for error. It may throw,
but only if something unexpected goes wrong during parsing; parse
errors will be caught, warned about, and reported as failure. */
int gdb_xml_parse_quick (const char *name, const char *dtd_name,
const struct gdb_xml_element *elements,
const char *document, void *user_data);
/* Issue a debugging message from one of PARSER's handlers. */
void gdb_xml_debug (struct gdb_xml_parser *parser, const char *format, ...)
/* Issue an error message from one of PARSER's handlers, and stop
parsing. */
void gdb_xml_error (struct gdb_xml_parser *parser, const char *format, ...)
/* Find the attribute named NAME in the set of parsed attributes
ATTRIBUTES. Returns NULL if not found. */
struct gdb_xml_value *xml_find_attribute
(std::vector<gdb_xml_value> &attributes, const char *name);
/* Parse an integer attribute into a ULONGEST. */
extern gdb_xml_attribute_handler gdb_xml_parse_attr_ulongest;
/* Map NAME to VALUE. A struct gdb_xml_enum * should be saved as the
value of handler_data when using gdb_xml_parse_attr_enum to parse a
fixed list of possible strings. The list is terminated by an entry
with NAME == NULL. */
struct gdb_xml_enum
const char *name;
/* A handler_data for yes/no boolean values. */
extern const struct gdb_xml_enum gdb_xml_enums_boolean[];
extern gdb_xml_attribute_handler gdb_xml_parse_attr_enum;
/* Parse an integer string into a ULONGEST and return it, or call
gdb_xml_error if it could not be parsed. */
ULONGEST gdb_xml_parse_ulongest (struct gdb_xml_parser *parser,
const char *value);
/* Open FILENAME, read all its text into memory, close it, and return
the text. If something goes wrong, return an uninstantiated optional
and warn. */
extern gdb::optional<gdb::char_vector> xml_fetch_content_from_file
(const char *filename, const char *dirname);