gdb/osdata.c

   1 /* Routines for handling XML generic OS data provided by target.
   2
   3    Copyright (C) 2008-2017 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 #include "defs.h"
  21 #include "target.h"
  22 #include "vec.h"
  23 #include "xml-support.h"
  24 #include "osdata.h"
  25 #include "ui-out.h"
  26 #include "gdbcmd.h"
  27
  28 #if !defined(HAVE_LIBEXPAT)
  29
  30 std::unique_ptr<osdata>
  31 osdata_parse (const char *xml)
  32 {
  33   static int have_warned;
  34
  35   if (!have_warned)
  36     {
  37       have_warned = 1;
  38       warning (_("Can not parse XML OS data; XML support was disabled "
  39                 "at compile time"));
  40     }
  41
  42   return NULL;
  43 }
  44
  45 #else /* HAVE_LIBEXPAT */
  46
  47 /* Internal parsing data passed to all XML callbacks.  */
  48 struct osdata_parsing_data
  49 {
  50   std::unique_ptr<struct osdata> osdata;
  51   std::string property_name;
  52 };
  53
  54 /* Handle the start of a <osdata> element.  */
  55
  56 static void
  57 osdata_start_osdata (struct gdb_xml_parser *parser,
  58                         const struct gdb_xml_element *element,
  59                         void *user_data, VEC(gdb_xml_value_s) *attributes)
  60 {
  61   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  62
  63   if (data->osdata != NULL)
  64     gdb_xml_error (parser, _("Seen more than on osdata element"));
  65
  66   char *type = (char *) xml_find_attribute (attributes, "type")->value;
  67   data->osdata.reset (new struct osdata (std::string (type)));
  68 }
  69
  70 /* Handle the start of a <item> element.  */
  71
  72 static void
  73 osdata_start_item (struct gdb_xml_parser *parser,
  74                   const struct gdb_xml_element *element,
  75                   void *user_data, VEC(gdb_xml_value_s) *attributes)
  76 {
  77   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  78   data->osdata->items.emplace_back ();
  79 }
  80
  81 /* Handle the start of a <column> element.  */
  82
  83 static void
  84 osdata_start_column (struct gdb_xml_parser *parser,
  85                     const struct gdb_xml_element *element,
  86                     void *user_data, VEC(gdb_xml_value_s) *attributes)
  87 {
  88   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  89   const char *name
  90     = (const char *) xml_find_attribute (attributes, "name")->value;
  91
  92   data->property_name.assign (name);
  93 }
  94
  95 /* Handle the end of a <column> element.  */
  96
  97 static void
  98 osdata_end_column (struct gdb_xml_parser *parser,
  99                   const struct gdb_xml_element *element,
 100                   void *user_data, const char *body_text)
 101 {
 102   osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
 103   struct osdata *osdata = data->osdata.get ();
 104   osdata_item &item = osdata->items.back ();
 105
 106   item.columns.emplace_back (std::move (data->property_name),
 107                              std::string (body_text));
 108 }
 109
 110 /* The allowed elements and attributes for OS data object.
 111    The root element is a <osdata>.  */
 112
 113 const struct gdb_xml_attribute column_attributes[] = {
 114   { "name", GDB_XML_AF_NONE, NULL, NULL },
 115   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 116 };
 117
 118 const struct gdb_xml_element item_children[] = {
 119   { "column", column_attributes, NULL,
 120     GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
 121     osdata_start_column, osdata_end_column },
 122   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 123 };
 124
 125 const struct gdb_xml_attribute osdata_attributes[] = {
 126   { "type", GDB_XML_AF_NONE, NULL, NULL },
 127   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 128 };
 129
 130 const struct gdb_xml_element osdata_children[] = {
 131   { "item", NULL, item_children,
 132     GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
 133     osdata_start_item, NULL },
 134   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 135 };
 136
 137 const struct gdb_xml_element osdata_elements[] = {
 138   { "osdata", osdata_attributes, osdata_children,
 139     GDB_XML_EF_NONE, osdata_start_osdata, NULL },
 140   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 141 };
 142
 143 std::unique_ptr<osdata>
 144 osdata_parse (const char *xml)
 145 {
 146   osdata_parsing_data data;
 147
 148   if (gdb_xml_parse_quick (_("osdata"), "osdata.dtd",
 149                            osdata_elements, xml, &data) == 0)
 150     {
 151       /* Parsed successfully, don't need to delete the result.  */
 152       return std::move (data.osdata);
 153     }
 154
 155   return NULL;
 156 }
 157 #endif
 158
 159 std::unique_ptr<osdata>
 160 get_osdata (const char *type)
 161 {
 162   std::unique_ptr<osdata> osdata;
 163   gdb::unique_xmalloc_ptr<char> xml = target_get_osdata (type);
 164
 165   if (xml)
 166     {
 167       if (xml.get ()[0] == '\0')
 168         {
 169           if (type)
 170             warning (_("Empty data returned by target.  Wrong osdata type?"));
 171           else
 172             warning (_("Empty type list returned by target.  No type data?"));
 173         }
 174       else
 175         osdata = osdata_parse (xml.get ());
 176     }
 177
 178   if (osdata == NULL)
 179     error (_("Can not fetch data now."));
 180
 181   return osdata;
 182 }
 183
 184 const std::string *
 185 get_osdata_column (const osdata_item &item, const char *name)
 186 {
 187   for (const osdata_column &col : item.columns)
 188     if (col.name == name)
 189       return &col.value;
 190
 191   return NULL;
 192 }
 193
 194 void
 195 info_osdata (const char *type)
 196 {
 197   struct ui_out *uiout = current_uiout;
 198   struct osdata_item *last = NULL;
 199   int ncols = 0;
 200   int col_to_skip = -1;
 201
 202   if (type == NULL)
 203     type = "";
 204
 205   std::unique_ptr<osdata> osdata = get_osdata (type);
 206
 207   int nrows = osdata->items.size ();
 208
 209   if (*type == '\0' && nrows == 0)
 210     error (_("Available types of OS data not reported."));
 211
 212   if (!osdata->items.empty ())
 213     {
 214       last = &osdata->items.back ();
 215       ncols = last->columns.size ();
 216
 217       /* As a special case, scan the listing of available data types
 218          for a column named "Title", and only include it with MI
 219          output; this column's normal use is for titles for interface
 220          elements like menus, and it clutters up CLI output.  */
 221       if (*type == '\0' && !uiout->is_mi_like_p ())
 222         {
 223           for (int ix = 0; ix < last->columns.size (); ix++)
 224             {
 225               if (last->columns[ix].name == "Title")
 226                 col_to_skip = ix;
 227             }
 228           /* Be sure to reduce the total column count, otherwise
 229              internal errors ensue.  */
 230           if (col_to_skip >= 0)
 231             --ncols;
 232         }
 233     }
 234
 235   ui_out_emit_table table_emitter (uiout, ncols, nrows, "OSDataTable");
 236
 237   /* With no columns/items, we just output an empty table, but we
 238      still output the table.  This matters for MI.  */
 239   if (ncols == 0)
 240     return;
 241
 242   if (last != NULL && !last->columns.empty ())
 243     {
 244       for (int ix = 0; ix < last->columns.size (); ix++)
 245         {
 246           char col_name[32];
 247
 248           if (ix == col_to_skip)
 249             continue;
 250
 251           snprintf (col_name, 32, "col%d", ix);
 252           uiout->table_header (10, ui_left,
 253                                col_name, last->columns[ix].name.c_str ());
 254         }
 255     }
 256
 257   uiout->table_body ();
 258
 259   if (nrows != 0)
 260     {
 261       for (const osdata_item &item : osdata->items)
 262        {
 263          {
 264            ui_out_emit_tuple tuple_emitter (uiout, "item");
 265
 266            for (int ix_cols = 0; ix_cols < item.columns.size (); ix_cols++)
 267              {
 268                char col_name[32];
 269
 270                if (ix_cols == col_to_skip)
 271                  continue;
 272
 273                snprintf (col_name, 32, "col%d", ix_cols);
 274                uiout->field_string (col_name,
 275                                     item.columns[ix_cols].value.c_str ());
 276              }
 277          }
 278
 279          uiout->text ("\n");
 280        }
 281     }
 282 }
 283
 284 static void
 285 info_osdata_command (const char *arg, int from_tty)
 286 {
 287   info_osdata (arg);
 288 }
 289
 290 void
 291 _initialize_osdata (void)
 292 {
 293   add_info ("os", info_osdata_command,
 294            _("Show OS data ARG."));
 295 }