342 lines
9.1 KiB
C
342 lines
9.1 KiB
C
/* XML target description support for GDB.
|
||
|
||
Copyright (C) 2006
|
||
Free Software Foundation, Inc.
|
||
|
||
Contributed by CodeSourcery.
|
||
|
||
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
|
||
(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
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
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. */
|
||
|
||
#include "defs.h"
|
||
#include "target.h"
|
||
#include "target-descriptions.h"
|
||
#include "xml-support.h"
|
||
#include "xml-tdesc.h"
|
||
|
||
#include "filenames.h"
|
||
|
||
#include "gdb_assert.h"
|
||
|
||
#if !defined(HAVE_LIBEXPAT)
|
||
|
||
/* Parse DOCUMENT into a target description. Or don't, since we don't have
|
||
an XML parser. */
|
||
|
||
static struct target_desc *
|
||
tdesc_parse_xml (const char *document, xml_fetch_another fetcher,
|
||
void *fetcher_baton)
|
||
{
|
||
static int have_warned;
|
||
|
||
if (!have_warned)
|
||
{
|
||
have_warned = 1;
|
||
warning (_("Can not parse XML target description; XML support was "
|
||
"disabled at compile time"));
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
#else /* HAVE_LIBEXPAT */
|
||
|
||
/* A record of every XML description we have parsed. We never discard
|
||
old descriptions, because we never discard gdbarches. As long as we
|
||
have a gdbarch referencing this description, we want to have a copy
|
||
of it here, so that if we parse the same XML document again we can
|
||
return the same "struct target_desc *"; if they are not singletons,
|
||
then we will create unnecessary duplicate gdbarches. See
|
||
gdbarch_list_lookup_by_info. */
|
||
|
||
struct tdesc_xml_cache
|
||
{
|
||
const char *xml_document;
|
||
struct target_desc *tdesc;
|
||
};
|
||
typedef struct tdesc_xml_cache tdesc_xml_cache_s;
|
||
DEF_VEC_O(tdesc_xml_cache_s);
|
||
|
||
static VEC(tdesc_xml_cache_s) *xml_cache;
|
||
|
||
/* Callback data for target description parsing. */
|
||
|
||
struct tdesc_parsing_data
|
||
{
|
||
/* The target description we are building. */
|
||
struct target_desc *tdesc;
|
||
};
|
||
|
||
/* Handle the end of an <architecture> element and its value. */
|
||
|
||
static void
|
||
tdesc_end_arch (struct gdb_xml_parser *parser,
|
||
const struct gdb_xml_element *element,
|
||
void *user_data, const char *body_text)
|
||
{
|
||
struct tdesc_parsing_data *data = user_data;
|
||
const struct bfd_arch_info *arch;
|
||
|
||
arch = bfd_scan_arch (body_text);
|
||
if (arch == NULL)
|
||
gdb_xml_error (parser, _("Target description specified unknown "
|
||
"architecture \"%s\""), body_text);
|
||
set_tdesc_architecture (data->tdesc, arch);
|
||
}
|
||
|
||
/* The elements and attributes of an XML target description. */
|
||
|
||
const struct gdb_xml_element target_children[] = {
|
||
{ "architecture", NULL, NULL, GDB_XML_EF_OPTIONAL,
|
||
NULL, tdesc_end_arch },
|
||
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
|
||
};
|
||
|
||
const struct gdb_xml_element tdesc_elements[] = {
|
||
{ "target", NULL, target_children, GDB_XML_EF_NONE,
|
||
NULL, NULL },
|
||
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
|
||
};
|
||
|
||
/* Parse DOCUMENT into a target description and return it. */
|
||
|
||
static struct target_desc *
|
||
tdesc_parse_xml (const char *document, xml_fetch_another fetcher,
|
||
void *fetcher_baton)
|
||
{
|
||
struct cleanup *back_to, *result_cleanup;
|
||
struct gdb_xml_parser *parser;
|
||
struct tdesc_parsing_data data;
|
||
struct tdesc_xml_cache *cache;
|
||
char *expanded_text;
|
||
int ix;
|
||
|
||
/* Expand all XInclude directives. */
|
||
expanded_text = xml_process_xincludes (_("target description"),
|
||
document, fetcher, fetcher_baton, 0);
|
||
if (expanded_text == NULL)
|
||
{
|
||
warning (_("Could not load XML target description; ignoring"));
|
||
return NULL;
|
||
}
|
||
|
||
/* Check for an exact match in the list of descriptions we have
|
||
previously parsed. strcmp is a slightly inefficient way to
|
||
do this; an SHA-1 checksum would work as well. */
|
||
for (ix = 0; VEC_iterate (tdesc_xml_cache_s, xml_cache, ix, cache); ix++)
|
||
if (strcmp (cache->xml_document, expanded_text) == 0)
|
||
{
|
||
xfree (expanded_text);
|
||
return cache->tdesc;
|
||
}
|
||
|
||
back_to = make_cleanup (null_cleanup, NULL);
|
||
parser = gdb_xml_create_parser_and_cleanup (_("target description"),
|
||
tdesc_elements, &data);
|
||
gdb_xml_use_dtd (parser, "gdb-target.dtd");
|
||
|
||
memset (&data, 0, sizeof (struct tdesc_parsing_data));
|
||
data.tdesc = allocate_target_description ();
|
||
result_cleanup = make_cleanup_free_target_description (data.tdesc);
|
||
make_cleanup (xfree, expanded_text);
|
||
|
||
if (gdb_xml_parse (parser, expanded_text) == 0)
|
||
{
|
||
/* Parsed successfully. */
|
||
struct tdesc_xml_cache new_cache;
|
||
|
||
new_cache.xml_document = expanded_text;
|
||
new_cache.tdesc = data.tdesc;
|
||
VEC_safe_push (tdesc_xml_cache_s, xml_cache, &new_cache);
|
||
discard_cleanups (result_cleanup);
|
||
do_cleanups (back_to);
|
||
return data.tdesc;
|
||
}
|
||
else
|
||
{
|
||
warning (_("Could not load XML target description; ignoring"));
|
||
do_cleanups (back_to);
|
||
return NULL;
|
||
}
|
||
}
|
||
#endif /* HAVE_LIBEXPAT */
|
||
|
||
|
||
/* Close FILE. */
|
||
|
||
static void
|
||
do_cleanup_fclose (void *file)
|
||
{
|
||
fclose (file);
|
||
}
|
||
|
||
/* Open FILENAME, read all its text into memory, close it, and return
|
||
the text. If something goes wrong, return NULL and warn. */
|
||
|
||
static char *
|
||
fetch_xml_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, NULL);
|
||
if (fullname == NULL)
|
||
nomem (0);
|
||
file = fopen (fullname, FOPEN_RT);
|
||
xfree (fullname);
|
||
}
|
||
else
|
||
file = fopen (filename, FOPEN_RT);
|
||
|
||
if (file == NULL)
|
||
return NULL;
|
||
|
||
back_to = make_cleanup (do_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;
|
||
}
|
||
|
||
/* Read an XML target description from FILENAME. Parse it, and return
|
||
the parsed description. */
|
||
|
||
const struct target_desc *
|
||
file_read_description_xml (const char *filename)
|
||
{
|
||
struct target_desc *tdesc;
|
||
char *tdesc_str;
|
||
struct cleanup *back_to;
|
||
const char *base;
|
||
char *dirname;
|
||
|
||
tdesc_str = fetch_xml_from_file (filename, NULL);
|
||
if (tdesc_str == NULL)
|
||
{
|
||
warning (_("Could not open \"%s\""), filename);
|
||
return NULL;
|
||
}
|
||
|
||
back_to = make_cleanup (xfree, tdesc_str);
|
||
|
||
/* Simple, portable version of dirname that does not modify its
|
||
argument. */
|
||
base = lbasename (filename);
|
||
while (base > filename && IS_DIR_SEPARATOR (base[-1]))
|
||
--base;
|
||
if (base > filename)
|
||
{
|
||
dirname = xmalloc (base - filename + 2);
|
||
memcpy (dirname, filename, base - filename);
|
||
|
||
/* On DOS based file systems, convert "d:foo" to "d:.", so that
|
||
we create "d:./bar" later instead of the (different)
|
||
"d:/bar". */
|
||
if (base - filename == 2 && IS_ABSOLUTE_PATH (base)
|
||
&& !IS_DIR_SEPARATOR (filename[0]))
|
||
dirname[base++ - filename] = '.';
|
||
|
||
dirname[base - filename] = '\0';
|
||
make_cleanup (xfree, dirname);
|
||
}
|
||
else
|
||
dirname = NULL;
|
||
|
||
tdesc = tdesc_parse_xml (tdesc_str, fetch_xml_from_file, dirname);
|
||
do_cleanups (back_to);
|
||
|
||
return tdesc;
|
||
}
|
||
|
||
/* Read a string representation of available features from the target,
|
||
using TARGET_OBJECT_AVAILABLE_FEATURES. The returned string is
|
||
malloc allocated and NUL-terminated. NAME should be a non-NULL
|
||
string identifying the XML document we want; the top level document
|
||
is "target.xml". Other calls may be performed for the DTD or
|
||
for <xi:include>. */
|
||
|
||
static char *
|
||
fetch_available_features_from_target (const char *name, void *baton_)
|
||
{
|
||
struct target_ops *ops = baton_;
|
||
|
||
/* Read this object as a string. This ensures that a NUL
|
||
terminator is added. */
|
||
return target_read_stralloc (ops,
|
||
TARGET_OBJECT_AVAILABLE_FEATURES,
|
||
name);
|
||
}
|
||
|
||
|
||
/* Read an XML target description using OPS. Parse it, and return the
|
||
parsed description. */
|
||
|
||
const struct target_desc *
|
||
target_read_description_xml (struct target_ops *ops)
|
||
{
|
||
struct target_desc *tdesc;
|
||
char *tdesc_str;
|
||
struct cleanup *back_to;
|
||
|
||
tdesc_str = fetch_available_features_from_target ("target.xml", ops);
|
||
if (tdesc_str == NULL)
|
||
return NULL;
|
||
|
||
back_to = make_cleanup (xfree, tdesc_str);
|
||
tdesc = tdesc_parse_xml (tdesc_str,
|
||
fetch_available_features_from_target,
|
||
ops);
|
||
do_cleanups (back_to);
|
||
|
||
return tdesc;
|
||
}
|