/* XML target description support for GDB. Copyright (C) 2006, 2008, 2009 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 3 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, see <http://www.gnu.org/licenses/>. */ #include "defs.h" #include "gdbtypes.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; /* The target feature we are currently parsing, or last parsed. */ struct tdesc_feature *current_feature; /* The register number to use for the next register we see, if it does not have its own. This starts at zero. */ int next_regnum; /* The union we are currently parsing, or last parsed. */ struct type *current_union; }; /* 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); } /* Handle the start of a <target> element. */ static void tdesc_start_target (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, void *user_data, VEC(gdb_xml_value_s) *attributes) { struct tdesc_parsing_data *data = user_data; char *version = VEC_index (gdb_xml_value_s, attributes, 0)->value; if (strcmp (version, "1.0") != 0) gdb_xml_error (parser, _("Target description has unsupported version \"%s\""), version); } /* Handle the start of a <feature> element. */ static void tdesc_start_feature (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, void *user_data, VEC(gdb_xml_value_s) *attributes) { struct tdesc_parsing_data *data = user_data; char *name = VEC_index (gdb_xml_value_s, attributes, 0)->value; data->current_feature = tdesc_create_feature (data->tdesc, name); } /* Handle the start of a <reg> element. Fill in the optional attributes and attach it to the containing feature. */ static void tdesc_start_reg (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, void *user_data, VEC(gdb_xml_value_s) *attributes) { struct tdesc_parsing_data *data = user_data; struct gdb_xml_value *attrs = VEC_address (gdb_xml_value_s, attributes); int ix = 0, length; char *name, *group, *type; int bitsize, regnum, save_restore; length = VEC_length (gdb_xml_value_s, attributes); name = attrs[ix++].value; bitsize = * (ULONGEST *) attrs[ix++].value; if (ix < length && strcmp (attrs[ix].name, "regnum") == 0) regnum = * (ULONGEST *) attrs[ix++].value; else regnum = data->next_regnum; if (ix < length && strcmp (attrs[ix].name, "type") == 0) type = attrs[ix++].value; else type = "int"; if (ix < length && strcmp (attrs[ix].name, "group") == 0) group = attrs[ix++].value; else group = NULL; if (ix < length && strcmp (attrs[ix].name, "save-restore") == 0) save_restore = * (ULONGEST *) attrs[ix++].value; else save_restore = 1; if (strcmp (type, "int") != 0 && strcmp (type, "float") != 0 && strcmp (type, "code_ptr") != 0 && strcmp (type, "data_ptr") != 0 && tdesc_named_type (data->current_feature, type) == NULL) gdb_xml_error (parser, _("Register \"%s\" has unknown type \"%s\""), name, type); tdesc_create_reg (data->current_feature, name, regnum, save_restore, group, bitsize, type); data->next_regnum = regnum + 1; } /* Handle the start of a <union> element. Initialize the type and record it with the current feature. */ static void tdesc_start_union (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, void *user_data, VEC(gdb_xml_value_s) *attributes) { struct tdesc_parsing_data *data = user_data; char *id = VEC_index (gdb_xml_value_s, attributes, 0)->value; struct type *type; type = init_composite_type (NULL, TYPE_CODE_UNION); TYPE_NAME (type) = xstrdup (id); tdesc_record_type (data->current_feature, type); data->current_union = type; } /* Handle the end of a <union> element. */ static void tdesc_end_union (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; int i; /* If any of the children of this union are vectors, flag the union as a vector also. This allows e.g. a union of two vector types to show up automatically in "info vector". */ for (i = 0; i < TYPE_NFIELDS (data->current_union); i++) if (TYPE_VECTOR (TYPE_FIELD_TYPE (data->current_union, i))) { TYPE_VECTOR (data->current_union) = 1; break; } } /* Handle the start of a <field> element. Attach the field to the current union. */ static void tdesc_start_field (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, void *user_data, VEC(gdb_xml_value_s) *attributes) { struct tdesc_parsing_data *data = user_data; struct gdb_xml_value *attrs = VEC_address (gdb_xml_value_s, attributes); struct type *type, *field_type; char *field_name, *field_type_id; field_name = attrs[0].value; field_type_id = attrs[1].value; field_type = tdesc_named_type (data->current_feature, field_type_id); if (field_type == NULL) gdb_xml_error (parser, _("Union field \"%s\" references undefined " "type \"%s\""), field_name, field_type_id); append_composite_type_field (data->current_union, xstrdup (field_name), field_type); } /* Handle the start of a <vector> element. Initialize the type and record it with the current feature. */ static void tdesc_start_vector (struct gdb_xml_parser *parser, const struct gdb_xml_element *element, void *user_data, VEC(gdb_xml_value_s) *attributes) { struct tdesc_parsing_data *data = user_data; struct gdb_xml_value *attrs = VEC_address (gdb_xml_value_s, attributes); struct type *type, *field_type, *range_type; char *id, *field_type_id; int count; id = attrs[0].value; field_type_id = attrs[1].value; count = * (ULONGEST *) attrs[2].value; field_type = tdesc_named_type (data->current_feature, field_type_id); if (field_type == NULL) gdb_xml_error (parser, _("Vector \"%s\" references undefined type \"%s\""), id, field_type_id); type = init_vector_type (field_type, count); TYPE_NAME (type) = xstrdup (id); tdesc_record_type (data->current_feature, type); } /* The elements and attributes of an XML target description. */ static const struct gdb_xml_attribute field_attributes[] = { { "name", GDB_XML_AF_NONE, NULL, NULL }, { "type", GDB_XML_AF_NONE, NULL, NULL }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; static const struct gdb_xml_element union_children[] = { { "field", field_attributes, NULL, GDB_XML_EF_REPEATABLE, tdesc_start_field, NULL }, { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } }; static const struct gdb_xml_attribute reg_attributes[] = { { "name", GDB_XML_AF_NONE, NULL, NULL }, { "bitsize", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, { "regnum", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL }, { "type", GDB_XML_AF_OPTIONAL, NULL, NULL }, { "group", GDB_XML_AF_OPTIONAL, NULL, NULL }, { "save-restore", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_enum, gdb_xml_enums_boolean }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; static const struct gdb_xml_attribute union_attributes[] = { { "id", GDB_XML_AF_NONE, NULL, NULL }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; static const struct gdb_xml_attribute vector_attributes[] = { { "id", GDB_XML_AF_NONE, NULL, NULL }, { "type", GDB_XML_AF_NONE, NULL, NULL }, { "count", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; static const struct gdb_xml_attribute feature_attributes[] = { { "name", GDB_XML_AF_NONE, NULL, NULL }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; static const struct gdb_xml_element feature_children[] = { { "reg", reg_attributes, NULL, GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE, tdesc_start_reg, NULL }, { "union", union_attributes, union_children, GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE, tdesc_start_union, tdesc_end_union }, { "vector", vector_attributes, NULL, GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE, tdesc_start_vector, NULL }, { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } }; static const struct gdb_xml_attribute target_attributes[] = { { "version", GDB_XML_AF_NONE, NULL, NULL }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; static const struct gdb_xml_element target_children[] = { { "architecture", NULL, NULL, GDB_XML_EF_OPTIONAL, NULL, tdesc_end_arch }, { "feature", feature_attributes, feature_children, GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE, tdesc_start_feature, NULL }, { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } }; static const struct gdb_xml_element tdesc_elements[] = { { "target", target_attributes, target_children, GDB_XML_EF_NONE, tdesc_start_target, 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 */ /* 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, (char *) 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_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; 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); dirname = ldirname (filename); if (dirname != NULL) make_cleanup (xfree, dirname); 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; }