/* Helper routines for parsing XML using Expat.
- Copyright (C) 2006
- Free Software Foundation, Inc.
+ Copyright (C) 2006-2015 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 2 of the License, or
+ 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,
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, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "gdbcmd.h"
+#include "xml-support.h"
+#include "filestuff.h"
+#include "safe-ctype.h"
/* Debugging flag. */
static int debug_xml;
available. */
#ifdef HAVE_LIBEXPAT
-#include "exceptions.h"
-#include "xml-support.h"
-
#include "gdb_expat.h"
-#include "gdb_string.h"
-#include "safe-ctype.h"
+
+/* The maximum depth of <xi:include> nesting. No need to be miserly,
+ we just want to avoid running out of stack on loops. */
+#define MAX_XINCLUDE_DEPTH 30
+
+/* Simplified XML parser infrastructure. */
/* A parsing level -- used to keep track of the current element
nesting. */
struct gdb_exception error; /* A thrown error, if any. */
int last_line; /* The line of the thrown error, or 0. */
+
+ const char *dtd_name; /* The name of the expected / default DTD,
+ if specified. */
+ int is_xinclude; /* Are we the special <xi:include> parser? */
};
/* Process some body text. We accumulate the text for later use; it's
struct gdb_xml_parser *parser = data;
struct scope_level *scope = VEC_last (scope_level_s, parser->scopes);
+ if (parser->error.reason < 0)
+ return;
+
if (scope->body == NULL)
{
- scope->body = XZALLOC (struct obstack);
+ scope->body = XCNEW (struct obstack);
obstack_init (scope->body);
}
throw_verror (XML_PARSE_ERROR, format, ap);
}
+/* Find the attribute named NAME in the set of parsed attributes
+ ATTRIBUTES. Returns NULL if not found. */
+
+struct gdb_xml_value *
+xml_find_attribute (VEC(gdb_xml_value_s) *attributes, const char *name)
+{
+ struct gdb_xml_value *value;
+ int ix;
+
+ for (ix = 0; VEC_iterate (gdb_xml_value_s, attributes, ix, value); ix++)
+ if (strcmp (value->name, name) == 0)
+ return value;
+
+ return NULL;
+}
+
/* Clean up a vector of parsed attribute values. */
static void
const XML_Char **attrs)
{
struct gdb_xml_parser *parser = data;
- struct scope_level *scope = VEC_last (scope_level_s, parser->scopes);
+ struct scope_level *scope;
struct scope_level new_scope;
const struct gdb_xml_element *element;
const struct gdb_xml_attribute *attribute;
unsigned int seen;
struct cleanup *back_to;
- back_to = make_cleanup (gdb_xml_values_cleanup, &attributes);
-
/* Push an error scope. If we return or throw an exception before
filling this in, it will tell us to ignore children of this
element. */
+ VEC_reserve (scope_level_s, parser->scopes, 1);
+ scope = VEC_last (scope_level_s, parser->scopes);
memset (&new_scope, 0, sizeof (new_scope));
- VEC_safe_push (scope_level_s, parser->scopes, &new_scope);
+ VEC_quick_push (scope_level_s, parser->scopes, &new_scope);
gdb_xml_debug (parser, _("Entering element <%s>"), name);
if (element == NULL || element->name == NULL)
{
+ /* If we're working on XInclude, <xi:include> can be the child
+ of absolutely anything. Copy the previous scope's element
+ list into the new scope even if there was no match. */
+ if (parser->is_xinclude)
+ {
+ struct scope_level *unknown_scope;
+
+ XML_DefaultCurrent (parser->expat_parser);
+
+ unknown_scope = VEC_last (scope_level_s, parser->scopes);
+ unknown_scope->elements = scope->elements;
+ return;
+ }
+
gdb_xml_debug (parser, _("Element <%s> unknown"), name);
- do_cleanups (back_to);
return;
}
scope->seen |= seen;
+ back_to = make_cleanup (gdb_xml_values_cleanup, &attributes);
+
for (attribute = element->attributes;
attribute != NULL && attribute->name != NULL;
attribute++)
const XML_Char **attrs)
{
struct gdb_xml_parser *parser = data;
- volatile struct gdb_exception ex;
if (parser->error.reason < 0)
return;
- TRY_CATCH (ex, RETURN_MASK_ALL)
+ TRY
{
gdb_xml_start_element (data, name, attrs);
}
- if (ex.reason < 0)
+ CATCH (ex, RETURN_MASK_ALL)
{
parser->error = ex;
+#ifdef HAVE_XML_STOPPARSER
XML_StopParser (parser->expat_parser, XML_FALSE);
+#endif
}
+ END_CATCH
}
/* Handle the end of an element. DATA is our local XML parser, and
struct scope_level *scope = VEC_last (scope_level_s, parser->scopes);
const struct gdb_xml_element *element;
unsigned int seen;
- char *body;
gdb_xml_debug (parser, _("Leaving element <%s>"), name);
gdb_xml_error (parser, _("Required element <%s> is missing"),
element->name);
- /* Call the element processor. */
- if (scope->body == NULL)
- body = "";
- else
+ /* Call the element processor. */
+ if (scope->element != NULL && scope->element->end_handler)
{
- int length;
+ char *body;
- length = obstack_object_size (scope->body);
- obstack_1grow (scope->body, '\0');
- body = obstack_finish (scope->body);
+ if (scope->body == NULL)
+ body = "";
+ else
+ {
+ int length;
- /* Strip leading and trailing whitespace. */
- while (length > 0 && ISSPACE (body[length-1]))
- body[--length] = '\0';
- while (*body && ISSPACE (*body))
- body++;
- }
+ length = obstack_object_size (scope->body);
+ obstack_1grow (scope->body, '\0');
+ body = obstack_finish (scope->body);
- if (scope->element != NULL && scope->element->end_handler)
- scope->element->end_handler (parser, scope->element, parser->user_data,
- body);
+ /* Strip leading and trailing whitespace. */
+ while (length > 0 && ISSPACE (body[length-1]))
+ body[--length] = '\0';
+ while (*body && ISSPACE (*body))
+ body++;
+ }
+
+ scope->element->end_handler (parser, scope->element, parser->user_data,
+ body);
+ }
+ else if (scope->element == NULL)
+ XML_DefaultCurrent (parser->expat_parser);
/* Pop the scope level. */
if (scope->body)
gdb_xml_end_element_wrapper (void *data, const XML_Char *name)
{
struct gdb_xml_parser *parser = data;
- volatile struct gdb_exception ex;
if (parser->error.reason < 0)
return;
- TRY_CATCH (ex, RETURN_MASK_ALL)
+ TRY
{
gdb_xml_end_element (data, name);
}
- if (ex.reason < 0)
+ CATCH (ex, RETURN_MASK_ALL)
{
parser->error = ex;
+#ifdef HAVE_XML_STOPPARSER
XML_StopParser (parser->expat_parser, XML_FALSE);
+#endif
}
+ END_CATCH
}
/* Free a parser and all its associated state. */
xfree (parser);
}
-/* Initialize and return a parser. Register a cleanup to destroy the
- parser. */
+/* Initialize a parser and store it to *PARSER_RESULT. Register a
+ cleanup to destroy the parser. */
-struct gdb_xml_parser *
+static struct cleanup *
gdb_xml_create_parser_and_cleanup (const char *name,
const struct gdb_xml_element *elements,
- void *user_data)
+ void *user_data,
+ struct gdb_xml_parser **parser_result)
{
struct gdb_xml_parser *parser;
struct scope_level start_scope;
+ struct cleanup *result;
/* Initialize the parser. */
- parser = XZALLOC (struct gdb_xml_parser);
+ parser = XCNEW (struct gdb_xml_parser);
parser->expat_parser = XML_ParserCreateNS (NULL, '!');
if (parser->expat_parser == NULL)
{
xfree (parser);
- nomem (0);
+ malloc_failure (0);
}
parser->name = name;
start_scope.elements = elements;
VEC_safe_push (scope_level_s, parser->scopes, &start_scope);
- make_cleanup (gdb_xml_cleanup, parser);
+ *parser_result = parser;
+ return make_cleanup (gdb_xml_cleanup, parser);
+}
+
+/* External entity handler. The only external entities we support
+ are those compiled into GDB (we do not fetch entities from the
+ target). */
- return parser;
+static int XMLCALL
+gdb_xml_fetch_external_entity (XML_Parser expat_parser,
+ const XML_Char *context,
+ const XML_Char *base,
+ const XML_Char *systemId,
+ const XML_Char *publicId)
+{
+ struct gdb_xml_parser *parser = XML_GetUserData (expat_parser);
+ XML_Parser entity_parser;
+ const char *text;
+ enum XML_Status status;
+
+ if (systemId == NULL)
+ {
+ text = fetch_xml_builtin (parser->dtd_name);
+ if (text == NULL)
+ internal_error (__FILE__, __LINE__,
+ _("could not locate built-in DTD %s"),
+ parser->dtd_name);
+ }
+ else
+ {
+ text = fetch_xml_builtin (systemId);
+ if (text == NULL)
+ return XML_STATUS_ERROR;
+ }
+
+ entity_parser = XML_ExternalEntityParserCreate (expat_parser, context, NULL);
+
+ /* Don't use our handlers for the contents of the DTD. Just let expat
+ process it. */
+ XML_SetElementHandler (entity_parser, NULL, NULL);
+ XML_SetDoctypeDeclHandler (entity_parser, NULL, NULL);
+ XML_SetXmlDeclHandler (entity_parser, NULL);
+ XML_SetDefaultHandler (entity_parser, NULL);
+ XML_SetUserData (entity_parser, NULL);
+
+ status = XML_Parse (entity_parser, text, strlen (text), 1);
+
+ XML_ParserFree (entity_parser);
+ return status;
+}
+
+/* Associate DTD_NAME, which must be the name of a compiled-in DTD,
+ with PARSER. */
+
+void
+gdb_xml_use_dtd (struct gdb_xml_parser *parser, const char *dtd_name)
+{
+ enum XML_Error err;
+
+ parser->dtd_name = dtd_name;
+
+ XML_SetParamEntityParsing (parser->expat_parser,
+ XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE);
+ XML_SetExternalEntityRefHandler (parser->expat_parser,
+ gdb_xml_fetch_external_entity);
+
+ /* Even if no DTD is provided, use the built-in DTD anyway. */
+ err = XML_UseForeignDTD (parser->expat_parser, XML_TRUE);
+ if (err != XML_ERROR_NONE)
+ internal_error (__FILE__, __LINE__,
+ _("XML_UseForeignDTD failed: %s"),
+ XML_ErrorString (err));
}
/* Invoke PARSER on BUFFER. BUFFER is the data to parse, which
enum XML_Status status;
const char *error_string;
+ gdb_xml_debug (parser, _("Starting:\n%s"), buffer);
+
status = XML_Parse (parser->expat_parser, buffer, strlen (buffer), 1);
if (status == XML_STATUS_OK && parser->error.reason == 0)
else if (status == XML_STATUS_ERROR)
{
enum XML_Error err = XML_GetErrorCode (parser->expat_parser);
+
error_string = XML_ErrorString (err);
}
else
return -1;
}
+int
+gdb_xml_parse_quick (const char *name, const char *dtd_name,
+ const struct gdb_xml_element *elements,
+ const char *document, void *user_data)
+{
+ struct gdb_xml_parser *parser;
+ struct cleanup *back_to;
+ int result;
+
+ back_to = gdb_xml_create_parser_and_cleanup (name, elements,
+ user_data, &parser);
+ if (dtd_name != NULL)
+ gdb_xml_use_dtd (parser, dtd_name);
+ result = gdb_xml_parse (parser, document);
+
+ do_cleanups (back_to);
+
+ return result;
+}
+
/* Parse a field VALSTR that we expect to contain an integer value.
The integer is returned in *VALP. The string is parsed with an
equivalent to strtoul.
gdb_xml_error (parser, _("Can't convert %s=\"%s\" to an integer"),
attribute->name, value);
- ret = xmalloc (sizeof (result));
+ ret = XNEW (ULONGEST);
memcpy (ret, &result, sizeof (result));
return ret;
}
+/* A handler_data for yes/no boolean values. */
+
+const struct gdb_xml_enum gdb_xml_enums_boolean[] = {
+ { "yes", 1 },
+ { "no", 0 },
+ { NULL, 0 }
+};
+
/* 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
void *ret;
for (enums = attribute->handler_data; enums->name != NULL; enums++)
- if (strcmp (enums->name, value) == 0)
+ if (strcasecmp (enums->name, value) == 0)
break;
if (enums->name == NULL)
memcpy (ret, &enums->value, sizeof (enums->value));
return ret;
}
+\f
+
+/* XInclude processing. This is done as a separate step from actually
+ parsing the document, so that we can produce a single combined XML
+ document - e.g. to hand to a front end or to simplify comparing two
+ documents. We make extensive use of XML_DefaultCurrent, to pass
+ input text directly into the output without reformatting or
+ requoting it.
+
+ We output the DOCTYPE declaration for the first document unchanged,
+ if present, and discard DOCTYPEs from included documents. Only the
+ one we pass through here is used when we feed the result back to
+ expat. The XInclude standard explicitly does not discuss
+ validation of the result; we choose to apply the same DTD applied
+ to the outermost document.
+
+ We can not simply include the external DTD subset in the document
+ as an internal subset, because <!IGNORE> and <!INCLUDE> are valid
+ only in external subsets. But if we do not pass the DTD into the
+ output at all, default values will not be filled in.
+
+ We don't pass through any <?xml> declaration because we generate
+ UTF-8, not whatever the input encoding was. */
+
+struct xinclude_parsing_data
+{
+ /* The obstack to build the output in. */
+ struct obstack obstack;
+
+ /* A count indicating whether we are in an element whose
+ children should not be copied to the output, and if so,
+ how deep we are nested. This is used for anything inside
+ an xi:include, and for the DTD. */
+ int skip_depth;
+
+ /* The number of <xi:include> elements currently being processed,
+ to detect loops. */
+ int include_depth;
+
+ /* A function to call to obtain additional features, and its
+ baton. */
+ xml_fetch_another fetcher;
+ void *fetcher_baton;
+};
+
+static void
+xinclude_start_include (struct gdb_xml_parser *parser,
+ const struct gdb_xml_element *element,
+ void *user_data, VEC(gdb_xml_value_s) *attributes)
+{
+ struct xinclude_parsing_data *data = user_data;
+ char *href = xml_find_attribute (attributes, "href")->value;
+ struct cleanup *back_to;
+ char *text, *output;
+
+ gdb_xml_debug (parser, _("Processing XInclude of \"%s\""), href);
+
+ if (data->include_depth > MAX_XINCLUDE_DEPTH)
+ gdb_xml_error (parser, _("Maximum XInclude depth (%d) exceeded"),
+ MAX_XINCLUDE_DEPTH);
+
+ text = data->fetcher (href, data->fetcher_baton);
+ if (text == NULL)
+ gdb_xml_error (parser, _("Could not load XML document \"%s\""), href);
+ back_to = make_cleanup (xfree, text);
+
+ output = xml_process_xincludes (parser->name, text, data->fetcher,
+ data->fetcher_baton,
+ data->include_depth + 1);
+ if (output == NULL)
+ gdb_xml_error (parser, _("Parsing \"%s\" failed"), href);
+
+ obstack_grow (&data->obstack, output, strlen (output));
+ xfree (output);
+
+ do_cleanups (back_to);
+
+ data->skip_depth++;
+}
+
+static void
+xinclude_end_include (struct gdb_xml_parser *parser,
+ const struct gdb_xml_element *element,
+ void *user_data, const char *body_text)
+{
+ struct xinclude_parsing_data *data = user_data;
+
+ data->skip_depth--;
+}
+
+static void XMLCALL
+xml_xinclude_default (void *data_, const XML_Char *s, int len)
+{
+ struct gdb_xml_parser *parser = data_;
+ struct xinclude_parsing_data *data = parser->user_data;
+ /* If we are inside of e.g. xi:include or the DTD, don't save this
+ string. */
+ if (data->skip_depth)
+ return;
+
+ /* Otherwise just add it to the end of the document we're building
+ up. */
+ obstack_grow (&data->obstack, s, len);
+}
+
+static void XMLCALL
+xml_xinclude_start_doctype (void *data_, const XML_Char *doctypeName,
+ const XML_Char *sysid, const XML_Char *pubid,
+ int has_internal_subset)
+{
+ struct gdb_xml_parser *parser = data_;
+ struct xinclude_parsing_data *data = parser->user_data;
+
+ /* Don't print out the doctype, or the contents of the DTD internal
+ subset, if any. */
+ data->skip_depth++;
+}
+
+static void XMLCALL
+xml_xinclude_end_doctype (void *data_)
+{
+ struct gdb_xml_parser *parser = data_;
+ struct xinclude_parsing_data *data = parser->user_data;
+
+ data->skip_depth--;
+}
+
+static void XMLCALL
+xml_xinclude_xml_decl (void *data_, const XML_Char *version,
+ const XML_Char *encoding, int standalone)
+{
+ /* Do nothing - this function prevents the default handler from
+ being called, thus suppressing the XML declaration from the
+ output. */
+}
+
+static void
+xml_xinclude_cleanup (void *data_)
+{
+ struct xinclude_parsing_data *data = data_;
+
+ obstack_free (&data->obstack, NULL);
+ xfree (data);
+}
+
+const struct gdb_xml_attribute xinclude_attributes[] = {
+ { "href", GDB_XML_AF_NONE, NULL, NULL },
+ { NULL, GDB_XML_AF_NONE, NULL, NULL }
+};
+
+const struct gdb_xml_element xinclude_elements[] = {
+ { "http://www.w3.org/2001/XInclude!include", xinclude_attributes, NULL,
+ GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE,
+ xinclude_start_include, xinclude_end_include },
+ { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
+};
+
+/* The main entry point for <xi:include> processing. */
+
+char *
+xml_process_xincludes (const char *name, const char *text,
+ xml_fetch_another fetcher, void *fetcher_baton,
+ int depth)
+{
+ struct gdb_xml_parser *parser;
+ struct xinclude_parsing_data *data;
+ struct cleanup *back_to;
+ char *result = NULL;
+
+ data = XCNEW (struct xinclude_parsing_data);
+ obstack_init (&data->obstack);
+ back_to = make_cleanup (xml_xinclude_cleanup, data);
+
+ gdb_xml_create_parser_and_cleanup (name, xinclude_elements,
+ data, &parser);
+ parser->is_xinclude = 1;
+
+ data->include_depth = depth;
+ data->fetcher = fetcher;
+ data->fetcher_baton = fetcher_baton;
+
+ XML_SetCharacterDataHandler (parser->expat_parser, NULL);
+ XML_SetDefaultHandler (parser->expat_parser, xml_xinclude_default);
+
+ /* Always discard the XML version declarations; the only important
+ thing this provides is encoding, and our result will have been
+ converted to UTF-8. */
+ XML_SetXmlDeclHandler (parser->expat_parser, xml_xinclude_xml_decl);
+
+ if (depth > 0)
+ /* Discard the doctype for included documents. */
+ XML_SetDoctypeDeclHandler (parser->expat_parser,
+ xml_xinclude_start_doctype,
+ xml_xinclude_end_doctype);
+
+ gdb_xml_use_dtd (parser, "xinclude.dtd");
+
+ if (gdb_xml_parse (parser, text) == 0)
+ {
+ obstack_1grow (&data->obstack, '\0');
+ result = xstrdup (obstack_finish (&data->obstack));
+
+ if (depth == 0)
+ gdb_xml_debug (parser, _("XInclude processing succeeded."));
+ }
+ else
+ result = NULL;
+
+ do_cleanups (back_to);
+ return result;
+}
#endif /* HAVE_LIBEXPAT */
+\f
+
+/* 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)
+{
+ const char *(*p)[2];
+
+ for (p = xml_builtin; (*p)[0]; p++)
+ if (strcmp ((*p)[0], filename) == 0)
+ return (*p)[1];
+
+ return NULL;
+}
+
+/* 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)
+{
+ const char *buf;
+ LONGEST len_avail;
+
+ gdb_assert (readbuf != NULL && writebuf == NULL);
+ gdb_assert (filename != NULL);
+
+ buf = fetch_xml_builtin (filename);
+ if (buf == NULL)
+ return -1;
+
+ len_avail = strlen (buf);
+ if (offset >= len_avail)
+ return 0;
+
+ if (len > len_avail - offset)
+ len = len_avail - offset;
+ memcpy (readbuf, buf + offset, len);
+ return len;
+}
+\f
static void
show_debug_xml (struct ui_file *file, int from_tty,
fprintf_filtered (file, _("XML debugging is %s.\n"), value);
}
+void
+obstack_xml_printf (struct obstack *obstack, const char *format, ...)
+{
+ va_list ap;
+ const char *f;
+ const char *prev;
+ int percent = 0;
+
+ va_start (ap, format);
+
+ prev = format;
+ for (f = format; *f; f++)
+ {
+ if (percent)
+ {
+ switch (*f)
+ {
+ case 's':
+ {
+ char *p;
+ char *a = va_arg (ap, char *);
+
+ obstack_grow (obstack, prev, f - prev - 1);
+ p = xml_escape_text (a);
+ obstack_grow_str (obstack, p);
+ xfree (p);
+ prev = f + 1;
+ }
+ break;
+ }
+ percent = 0;
+ }
+ else if (*f == '%')
+ percent = 1;
+ }
+
+ obstack_grow_str (obstack, prev);
+ va_end (ap);
+}
+
+char *
+xml_fetch_content_from_file (const char *filename, void *baton)
+{
+ const char *dirname = baton;
+ FILE *file;
+ struct cleanup *back_to;
+ char *text;
+ size_t len, offset;
+
+ if (dirname && *dirname)
+ {
+ char *fullname = concat (dirname, "/", filename, (char *) NULL);
+
+ if (fullname == NULL)
+ malloc_failure (0);
+ file = gdb_fopen_cloexec (fullname, FOPEN_RT);
+ xfree (fullname);
+ }
+ else
+ file = gdb_fopen_cloexec (filename, FOPEN_RT);
+
+ if (file == NULL)
+ return NULL;
+
+ back_to = make_cleanup_fclose (file);
+
+ /* Read in the whole file, one chunk at a time. */
+ len = 4096;
+ offset = 0;
+ text = xmalloc (len);
+ make_cleanup (free_current_contents, &text);
+ while (1)
+ {
+ size_t bytes_read;
+
+ /* Continue reading where the last read left off. Leave at least
+ one byte so that we can NUL-terminate the result. */
+ bytes_read = fread (text + offset, 1, len - offset - 1, file);
+ if (ferror (file))
+ {
+ warning (_("Read error from \"%s\""), filename);
+ do_cleanups (back_to);
+ return NULL;
+ }
+
+ offset += bytes_read;
+
+ if (feof (file))
+ break;
+
+ len = len * 2;
+ text = xrealloc (text, len);
+ }
+
+ fclose (file);
+ discard_cleanups (back_to);
+
+ text[offset] = '\0';
+ return text;
+}
+
void _initialize_xml_support (void);
void