1 /* Helper routines for parsing XML using Expat. 2 3 Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 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. 11 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. 16 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/>. */ 19 20 21 #ifndef XML_SUPPORT_H 22 #define XML_SUPPORT_H 23 24 #include "gdb_obstack.h" 25 #include "vec.h" 26 27 struct gdb_xml_parser; 28 struct gdb_xml_element; 29 struct gdb_xml_attribute; 30 31 /* Return an XML document which was compiled into GDB, from 32 the given FILENAME, or NULL if the file was not compiled in. */ 33 34 const char *fetch_xml_builtin (const char *filename); 35 36 /* A to_xfer_partial helper function which reads XML files which were 37 compiled into GDB. The target may call this function from its own 38 to_xfer_partial handler, after converting object and annex to the 39 appropriate filename. */ 40 41 LONGEST xml_builtin_xfer_partial (const char *filename, 42 gdb_byte *readbuf, const gdb_byte *writebuf, 43 ULONGEST offset, LONGEST len); 44 45 /* The text of compiled-in XML documents, from xml-builtin.c 46 (generated). */ 47 48 extern const char *xml_builtin[][2]; 49 50 /* Return a malloc allocated string with special characters from TEXT 51 replaced by entity references. */ 52 53 char *xml_escape_text (const char *text); 54 55 /* Support for XInclude. */ 56 57 /* Callback to fetch a new XML file, based on the provided HREF. */ 58 59 typedef char *(*xml_fetch_another) (const char *href, void *baton); 60 61 /* Return a new string which is the expansion of TEXT after processing 62 <xi:include> tags. FETCHER will be called (with FETCHER_BATON) to 63 retrieve any new files. DEPTH should be zero on the initial call. 64 65 On failure, this function uses NAME in a warning and returns NULL. 66 It may throw an exception, but does not for XML parsing 67 problems. */ 68 69 char *xml_process_xincludes (const char *name, const char *text, 70 xml_fetch_another fetcher, void *fetcher_baton, 71 int depth); 72 73 /* Simplified XML parser infrastructure. */ 74 75 /* A name and value pair, used to record parsed attributes. */ 76 77 struct gdb_xml_value 78 { 79 const char *name; 80 void *value; 81 }; 82 typedef struct gdb_xml_value gdb_xml_value_s; 83 DEF_VEC_O(gdb_xml_value_s); 84 85 /* The type of an attribute handler. 86 87 PARSER is the current XML parser, which should be used to issue any 88 debugging or error messages. The second argument is the 89 corresponding attribute description, so that a single handler can 90 be used for multiple attributes; the attribute name is available 91 for error messages and the handler data is available for additional 92 customization (see gdb_xml_parse_attr_enum). VALUE is the string 93 value of the attribute. 94 95 The returned value should be freeable with xfree, and will be freed 96 after the start handler is called. Errors should be reported by 97 calling gdb_xml_error. */ 98 99 typedef void *(gdb_xml_attribute_handler) (struct gdb_xml_parser *parser, 100 const struct gdb_xml_attribute *, 101 const char *value); 102 103 /* Flags for attributes. If no flags are specified, the attribute is 104 required. */ 105 106 enum gdb_xml_attribute_flag 107 { 108 GDB_XML_AF_NONE, 109 GDB_XML_AF_OPTIONAL = 1 << 0, /* The attribute is optional. */ 110 }; 111 112 /* An expected attribute and the handler to call when it is 113 encountered. Arrays of struct gdb_xml_attribute are terminated 114 by an entry with NAME == NULL. */ 115 116 struct gdb_xml_attribute 117 { 118 const char *name; 119 int flags; 120 gdb_xml_attribute_handler *handler; 121 const void *handler_data; 122 }; 123 124 /* Flags for elements. If no flags are specified, the element is 125 required exactly once. */ 126 127 enum gdb_xml_element_flag 128 { 129 GDB_XML_EF_NONE, 130 GDB_XML_EF_OPTIONAL = 1 << 0, /* The element is optional. */ 131 GDB_XML_EF_REPEATABLE = 1 << 1, /* The element is repeatable. */ 132 }; 133 134 /* A handler called at the beginning of an element. 135 136 PARSER is the current XML parser, which should be used to issue any 137 debugging or error messages. ELEMENT is the current element. 138 USER_DATA is the opaque pointer supplied when the parser was 139 created. ATTRIBUTES is a vector of the values of any attributes 140 attached to this element. 141 142 The start handler will only be called if all the required 143 attributes were present and parsed successfully, and elements of 144 ATTRIBUTES are guaranteed to be in the same order used in 145 ELEMENT->ATTRIBUTES (not the order from the XML file). Accordingly 146 fixed offsets can be used to find any non-optional attributes as 147 long as no optional attributes precede them. */ 148 149 typedef void (gdb_xml_element_start_handler) 150 (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, 151 void *user_data, VEC(gdb_xml_value_s) *attributes); 152 153 /* A handler called at the end of an element. 154 155 PARSER, ELEMENT, and USER_DATA are as for the start handler. BODY 156 is any accumulated body text inside the element, with leading and 157 trailing whitespace removed. It will never be NULL. */ 158 159 typedef void (gdb_xml_element_end_handler) 160 (struct gdb_xml_parser *, const struct gdb_xml_element *, 161 void *user_data, const char *body_text); 162 163 /* An expected element and the handlers to call when it is 164 encountered. Arrays of struct gdb_xml_element are terminated 165 by an entry with NAME == NULL. */ 166 167 struct gdb_xml_element 168 { 169 const char *name; 170 const struct gdb_xml_attribute *attributes; 171 const struct gdb_xml_element *children; 172 int flags; 173 174 gdb_xml_element_start_handler *start_handler; 175 gdb_xml_element_end_handler *end_handler; 176 }; 177 178 /* Initialize and return a parser. Register a cleanup to destroy the 179 parser. */ 180 181 struct gdb_xml_parser *gdb_xml_create_parser_and_cleanup 182 (const char *name, const struct gdb_xml_element *elements, 183 void *user_data); 184 185 /* Associate DTD_NAME, which must be the name of a compiled-in DTD, 186 with PARSER. */ 187 188 void gdb_xml_use_dtd (struct gdb_xml_parser *parser, const char *dtd_name); 189 190 /* Invoke PARSER on BUFFER. BUFFER is the data to parse, which 191 should be NUL-terminated. 192 193 The return value is 0 for success or -1 for error. It may throw, 194 but only if something unexpected goes wrong during parsing; parse 195 errors will be caught, warned about, and reported as failure. */ 196 197 int gdb_xml_parse (struct gdb_xml_parser *parser, const char *buffer); 198 199 /* Issue a debugging message from one of PARSER's handlers. */ 200 201 void gdb_xml_debug (struct gdb_xml_parser *parser, const char *format, ...) 202 ATTR_FORMAT (printf, 2, 0); 203 204 /* Issue an error message from one of PARSER's handlers, and stop 205 parsing. */ 206 207 void gdb_xml_error (struct gdb_xml_parser *parser, const char *format, ...) 208 ATTR_NORETURN ATTR_FORMAT (printf, 2, 0); 209 210 /* Parse an integer attribute into a ULONGEST. */ 211 212 extern gdb_xml_attribute_handler gdb_xml_parse_attr_ulongest; 213 214 /* Map NAME to VALUE. A struct gdb_xml_enum * should be saved as the 215 value of handler_data when using gdb_xml_parse_attr_enum to parse a 216 fixed list of possible strings. The list is terminated by an entry 217 with NAME == NULL. */ 218 219 struct gdb_xml_enum 220 { 221 const char *name; 222 ULONGEST value; 223 }; 224 225 /* A handler_data for yes/no boolean values. */ 226 extern const struct gdb_xml_enum gdb_xml_enums_boolean[]; 227 228 extern gdb_xml_attribute_handler gdb_xml_parse_attr_enum; 229 230 /* Parse an integer string into a ULONGEST and return it, or call 231 gdb_xml_error if it could not be parsed. */ 232 233 ULONGEST gdb_xml_parse_ulongest (struct gdb_xml_parser *parser, 234 const char *value); 235 236 /* Simple printf to obstack function. Current implemented formatters: 237 %s - grow an xml escaped text in OBSTACK. */ 238 239 extern void obstack_xml_printf (struct obstack *obstack, 240 const char *format, ...) 241 ATTRIBUTE_PRINTF_2; 242 243 /* Open FILENAME, read all its text into memory, close it, and return 244 the text. If something goes wrong, return NULL and warn. */ 245 246 extern char *xml_fetch_content_from_file (const char *filename, 247 void *baton); 248 249 #endif 250