1 /* Helper routines for parsing XML using Expat.
3 Copyright (C) 2006-2019 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_obstack.h"
25 #include "gdbsupport/xml-utils.h"
26 #include "gdbsupport/byte-vector.h"
27 #include "gdbsupport/gdb_optional.h"
29 struct gdb_xml_parser
;
30 struct gdb_xml_element
;
31 struct gdb_xml_attribute
;
33 /* Return an XML document which was compiled into GDB, from
34 the given FILENAME, or NULL if the file was not compiled in. */
36 const char *fetch_xml_builtin (const char *filename
);
38 /* A to_xfer_partial helper function which reads XML files which were
39 compiled into GDB. The target may call this function from its own
40 to_xfer_partial handler, after converting object and annex to the
41 appropriate filename. */
43 LONGEST
xml_builtin_xfer_partial (const char *filename
,
44 gdb_byte
*readbuf
, const gdb_byte
*writebuf
,
45 ULONGEST offset
, LONGEST len
);
47 /* The text of compiled-in XML documents, from xml-builtin.c
50 extern const char *xml_builtin
[][2];
52 /* Support for XInclude. */
54 /* Callback to fetch a new XML file, based on the provided HREF. */
56 typedef gdb::optional
<gdb::char_vector
> (*xml_fetch_another
) (const char *href
,
59 /* Append the expansion of TEXT after processing <xi:include> tags in
60 RESULT. FETCHER will be called (with FETCHER_BATON) to retrieve
61 any new files. DEPTH should be zero on the initial call.
63 On failure, this function uses NAME in a warning and returns false.
64 It may throw an exception, but does not for XML parsing
67 bool xml_process_xincludes (std::string
&result
,
68 const char *name
, const char *text
,
69 xml_fetch_another fetcher
, void *fetcher_baton
,
72 /* Simplified XML parser infrastructure. */
74 /* A name and value pair, used to record parsed attributes. */
78 gdb_xml_value (const char *name_
, void *value_
)
79 : name (name_
), value (value_
)
83 gdb::unique_xmalloc_ptr
<void> value
;
86 /* The type of an attribute handler.
88 PARSER is the current XML parser, which should be used to issue any
89 debugging or error messages. The second argument is the
90 corresponding attribute description, so that a single handler can
91 be used for multiple attributes; the attribute name is available
92 for error messages and the handler data is available for additional
93 customization (see gdb_xml_parse_attr_enum). VALUE is the string
94 value of the attribute.
96 The returned value should be freeable with xfree, and will be freed
97 after the start handler is called. Errors should be reported by
98 calling gdb_xml_error. */
100 typedef void *(gdb_xml_attribute_handler
) (struct gdb_xml_parser
*parser
,
101 const struct gdb_xml_attribute
*,
104 /* Flags for attributes. If no flags are specified, the attribute is
107 enum gdb_xml_attribute_flag
110 GDB_XML_AF_OPTIONAL
= 1 << 0, /* The attribute is optional. */
113 /* An expected attribute and the handler to call when it is
114 encountered. Arrays of struct gdb_xml_attribute are terminated
115 by an entry with NAME == NULL. */
117 struct gdb_xml_attribute
121 gdb_xml_attribute_handler
*handler
;
122 const void *handler_data
;
125 /* Flags for elements. If no flags are specified, the element is
126 required exactly once. */
128 enum gdb_xml_element_flag
131 GDB_XML_EF_OPTIONAL
= 1 << 0, /* The element is optional. */
132 GDB_XML_EF_REPEATABLE
= 1 << 1, /* The element is repeatable. */
135 /* A handler called at the beginning of an element.
137 PARSER is the current XML parser, which should be used to issue any
138 debugging or error messages. ELEMENT is the current element.
139 USER_DATA is the opaque pointer supplied when the parser was
140 created. ATTRIBUTES is a vector of the values of any attributes
141 attached to this element.
143 The start handler will only be called if all the required
144 attributes were present and parsed successfully, and elements of
145 ATTRIBUTES are guaranteed to be in the same order used in
146 ELEMENT->ATTRIBUTES (not the order from the XML file). Accordingly
147 fixed offsets can be used to find any non-optional attributes as
148 long as no optional attributes precede them. */
150 typedef void (gdb_xml_element_start_handler
)
151 (struct gdb_xml_parser
*parser
, const struct gdb_xml_element
*element
,
152 void *user_data
, std::vector
<gdb_xml_value
> &attributes
);
154 /* A handler called at the end of an element.
156 PARSER, ELEMENT, and USER_DATA are as for the start handler. BODY
157 is any accumulated body text inside the element, with leading and
158 trailing whitespace removed. It will never be NULL. */
160 typedef void (gdb_xml_element_end_handler
)
161 (struct gdb_xml_parser
*, const struct gdb_xml_element
*,
162 void *user_data
, const char *body_text
);
164 /* An expected element and the handlers to call when it is
165 encountered. Arrays of struct gdb_xml_element are terminated
166 by an entry with NAME == NULL. */
168 struct gdb_xml_element
171 const struct gdb_xml_attribute
*attributes
;
172 const struct gdb_xml_element
*children
;
175 gdb_xml_element_start_handler
*start_handler
;
176 gdb_xml_element_end_handler
*end_handler
;
179 /* Parse a XML document. DOCUMENT is the data to parse, which should
180 be NUL-terminated. If non-NULL, use the compiled-in DTD named
181 DTD_NAME to drive the parsing.
183 The return value is 0 for success or -1 for error. It may throw,
184 but only if something unexpected goes wrong during parsing; parse
185 errors will be caught, warned about, and reported as failure. */
187 int gdb_xml_parse_quick (const char *name
, const char *dtd_name
,
188 const struct gdb_xml_element
*elements
,
189 const char *document
, void *user_data
);
191 /* Issue a debugging message from one of PARSER's handlers. */
193 void gdb_xml_debug (struct gdb_xml_parser
*parser
, const char *format
, ...)
194 ATTRIBUTE_PRINTF (2, 3);
196 /* Issue an error message from one of PARSER's handlers, and stop
199 void gdb_xml_error (struct gdb_xml_parser
*parser
, const char *format
, ...)
200 ATTRIBUTE_NORETURN
ATTRIBUTE_PRINTF (2, 3);
202 /* Find the attribute named NAME in the set of parsed attributes
203 ATTRIBUTES. Returns NULL if not found. */
205 struct gdb_xml_value
*xml_find_attribute
206 (std::vector
<gdb_xml_value
> &attributes
, const char *name
);
208 /* Parse an integer attribute into a ULONGEST. */
210 extern gdb_xml_attribute_handler gdb_xml_parse_attr_ulongest
;
212 /* Map NAME to VALUE. A struct gdb_xml_enum * should be saved as the
213 value of handler_data when using gdb_xml_parse_attr_enum to parse a
214 fixed list of possible strings. The list is terminated by an entry
215 with NAME == NULL. */
223 /* A handler_data for yes/no boolean values. */
224 extern const struct gdb_xml_enum gdb_xml_enums_boolean
[];
226 extern gdb_xml_attribute_handler gdb_xml_parse_attr_enum
;
228 /* Parse an integer string into a ULONGEST and return it, or call
229 gdb_xml_error if it could not be parsed. */
231 ULONGEST
gdb_xml_parse_ulongest (struct gdb_xml_parser
*parser
,
234 /* Open FILENAME, read all its text into memory, close it, and return
235 the text. If something goes wrong, return an uninstantiated optional
238 extern gdb::optional
<gdb::char_vector
> xml_fetch_content_from_file
239 (const char *filename
, void *baton
);