1 /* Helper routines for parsing XML using Expat.
3 Copyright (C) 2006-2018 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"
26 #include "xml-utils.h"
28 struct gdb_xml_parser;
29 struct gdb_xml_element;
30 struct gdb_xml_attribute;
32 /* Return an XML document which was compiled into GDB, from
33 the given FILENAME, or NULL if the file was not compiled in. */
35 const char *fetch_xml_builtin (const char *filename);
37 /* A to_xfer_partial helper function which reads XML files which were
38 compiled into GDB. The target may call this function from its own
39 to_xfer_partial handler, after converting object and annex to the
40 appropriate filename. */
42 LONGEST xml_builtin_xfer_partial (const char *filename,
43 gdb_byte *readbuf, const gdb_byte *writebuf,
44 ULONGEST offset, LONGEST len);
46 /* The text of compiled-in XML documents, from xml-builtin.c
49 extern const char *xml_builtin[][2];
51 /* Support for XInclude. */
53 /* Callback to fetch a new XML file, based on the provided HREF. */
55 typedef gdb::unique_xmalloc_ptr<char> (*xml_fetch_another) (const char *href,
58 /* Append the expansion of TEXT after processing <xi:include> tags in
59 RESULT. FETCHER will be called (with FETCHER_BATON) to retrieve
60 any new files. DEPTH should be zero on the initial call.
62 On failure, this function uses NAME in a warning and returns false.
63 It may throw an exception, but does not for XML parsing
66 bool xml_process_xincludes (std::string &result,
67 const char *name, const char *text,
68 xml_fetch_another fetcher, void *fetcher_baton,
71 /* Simplified XML parser infrastructure. */
73 /* A name and value pair, used to record parsed attributes. */
80 typedef struct gdb_xml_value gdb_xml_value_s;
81 DEF_VEC_O(gdb_xml_value_s);
83 /* The type of an attribute handler.
85 PARSER is the current XML parser, which should be used to issue any
86 debugging or error messages. The second argument is the
87 corresponding attribute description, so that a single handler can
88 be used for multiple attributes; the attribute name is available
89 for error messages and the handler data is available for additional
90 customization (see gdb_xml_parse_attr_enum). VALUE is the string
91 value of the attribute.
93 The returned value should be freeable with xfree, and will be freed
94 after the start handler is called. Errors should be reported by
95 calling gdb_xml_error. */
97 typedef void *(gdb_xml_attribute_handler) (struct gdb_xml_parser *parser,
98 const struct gdb_xml_attribute *,
101 /* Flags for attributes. If no flags are specified, the attribute is
104 enum gdb_xml_attribute_flag
107 GDB_XML_AF_OPTIONAL = 1 << 0, /* The attribute is optional. */
110 /* An expected attribute and the handler to call when it is
111 encountered. Arrays of struct gdb_xml_attribute are terminated
112 by an entry with NAME == NULL. */
114 struct gdb_xml_attribute
118 gdb_xml_attribute_handler *handler;
119 const void *handler_data;
122 /* Flags for elements. If no flags are specified, the element is
123 required exactly once. */
125 enum gdb_xml_element_flag
128 GDB_XML_EF_OPTIONAL = 1 << 0, /* The element is optional. */
129 GDB_XML_EF_REPEATABLE = 1 << 1, /* The element is repeatable. */
132 /* A handler called at the beginning of an element.
134 PARSER is the current XML parser, which should be used to issue any
135 debugging or error messages. ELEMENT is the current element.
136 USER_DATA is the opaque pointer supplied when the parser was
137 created. ATTRIBUTES is a vector of the values of any attributes
138 attached to this element.
140 The start handler will only be called if all the required
141 attributes were present and parsed successfully, and elements of
142 ATTRIBUTES are guaranteed to be in the same order used in
143 ELEMENT->ATTRIBUTES (not the order from the XML file). Accordingly
144 fixed offsets can be used to find any non-optional attributes as
145 long as no optional attributes precede them. */
147 typedef void (gdb_xml_element_start_handler)
148 (struct gdb_xml_parser *parser, const struct gdb_xml_element *element,
149 void *user_data, VEC(gdb_xml_value_s) *attributes);
151 /* A handler called at the end of an element.
153 PARSER, ELEMENT, and USER_DATA are as for the start handler. BODY
154 is any accumulated body text inside the element, with leading and
155 trailing whitespace removed. It will never be NULL. */
157 typedef void (gdb_xml_element_end_handler)
158 (struct gdb_xml_parser *, const struct gdb_xml_element *,
159 void *user_data, const char *body_text);
161 /* An expected element and the handlers to call when it is
162 encountered. Arrays of struct gdb_xml_element are terminated
163 by an entry with NAME == NULL. */
165 struct gdb_xml_element
168 const struct gdb_xml_attribute *attributes;
169 const struct gdb_xml_element *children;
172 gdb_xml_element_start_handler *start_handler;
173 gdb_xml_element_end_handler *end_handler;
176 /* Parse a XML document. DOCUMENT is the data to parse, which should
177 be NUL-terminated. If non-NULL, use the compiled-in DTD named
178 DTD_NAME to drive the parsing.
180 The return value is 0 for success or -1 for error. It may throw,
181 but only if something unexpected goes wrong during parsing; parse
182 errors will be caught, warned about, and reported as failure. */
184 int gdb_xml_parse_quick (const char *name, const char *dtd_name,
185 const struct gdb_xml_element *elements,
186 const char *document, void *user_data);
188 /* Issue a debugging message from one of PARSER's handlers. */
190 void gdb_xml_debug (struct gdb_xml_parser *parser, const char *format, ...)
191 ATTRIBUTE_PRINTF (2, 3);
193 /* Issue an error message from one of PARSER's handlers, and stop
196 void gdb_xml_error (struct gdb_xml_parser *parser, const char *format, ...)
197 ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (2, 3);
199 /* Find the attribute named NAME in the set of parsed attributes
200 ATTRIBUTES. Returns NULL if not found. */
202 struct gdb_xml_value *xml_find_attribute (VEC(gdb_xml_value_s) *attributes,
205 /* Parse an integer attribute into a ULONGEST. */
207 extern gdb_xml_attribute_handler gdb_xml_parse_attr_ulongest;
209 /* Map NAME to VALUE. A struct gdb_xml_enum * should be saved as the
210 value of handler_data when using gdb_xml_parse_attr_enum to parse a
211 fixed list of possible strings. The list is terminated by an entry
212 with NAME == NULL. */
220 /* A handler_data for yes/no boolean values. */
221 extern const struct gdb_xml_enum gdb_xml_enums_boolean[];
223 extern gdb_xml_attribute_handler gdb_xml_parse_attr_enum;
225 /* Parse an integer string into a ULONGEST and return it, or call
226 gdb_xml_error if it could not be parsed. */
228 ULONGEST gdb_xml_parse_ulongest (struct gdb_xml_parser *parser,
231 /* Open FILENAME, read all its text into memory, close it, and return
232 the text. If something goes wrong, return NULL and warn. */
234 extern gdb::unique_xmalloc_ptr<char> xml_fetch_content_from_file
235 (const char *filename, void *baton);