gdb/osdata.c

   1 /* Routines for handling XML generic OS data provided by target.
   2
   3    Copyright (C) 2008-2020 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 "xml-support.h"
  23 #include "osdata.h"
  24 #include "ui-out.h"
  25 #include "gdbcmd.h"
  26
  27 #if !defined(HAVE_LIBEXPAT)
  28
  29 std::unique_ptr<osdata>
  30 osdata_parse (const char *xml)
  31 {
  32   static int have_warned;
  33
  34   if (!have_warned)
  35     {
  36       have_warned = 1;
  37       warning (_("Can not parse XML OS data; XML support was disabled "
  38                 "at compile time"));
  39     }
  40
  41   return NULL;
  42 }
  43
  44 #else /* HAVE_LIBEXPAT */
  45
  46 /* Internal parsing data passed to all XML callbacks.  */
  47 struct osdata_parsing_data
  48 {
  49   std::unique_ptr<struct osdata> osdata;
  50   std::string property_name;
  51 };
  52
  53 /* Handle the start of a <osdata> element.  */
  54
  55 static void
  56 osdata_start_osdata (struct gdb_xml_parser *parser,
  57                         const struct gdb_xml_element *element,
  58                         void *user_data,
  59                         std::vector<gdb_xml_value> &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.get ();
  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,
  76                   std::vector<gdb_xml_value> &attributes)
  77 {
  78   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  79   data->osdata->items.emplace_back ();
  80 }
  81
  82 /* Handle the start of a <column> element.  */
  83
  84 static void
  85 osdata_start_column (struct gdb_xml_parser *parser,
  86                     const struct gdb_xml_element *element,
  87                     void *user_data,
  88                     std::vector<gdb_xml_value> &attributes)
  89 {
  90   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  91   const char *name
  92     = (const char *) xml_find_attribute (attributes, "name")->value.get ();
  93
  94   data->property_name.assign (name);
  95 }
  96
  97 /* Handle the end of a <column> element.  */
  98
  99 static void
 100 osdata_end_column (struct gdb_xml_parser *parser,
 101                   const struct gdb_xml_element *element,
 102                   void *user_data, const char *body_text)
 103 {
 104   osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
 105   struct osdata *osdata = data->osdata.get ();
 106   osdata_item &item = osdata->items.back ();
 107
 108   item.columns.emplace_back (std::move (data->property_name),
 109                              std::string (body_text));
 110 }
 111
 112 /* The allowed elements and attributes for OS data object.
 113    The root element is a <osdata>.  */
 114
 115 const struct gdb_xml_attribute column_attributes[] = {
 116   { "name", GDB_XML_AF_NONE, NULL, NULL },
 117   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 118 };
 119
 120 const struct gdb_xml_element item_children[] = {
 121   { "column", column_attributes, NULL,
 122     GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
 123     osdata_start_column, osdata_end_column },
 124   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 125 };
 126
 127 const struct gdb_xml_attribute osdata_attributes[] = {
 128   { "type", GDB_XML_AF_NONE, NULL, NULL },
 129   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 130 };
 131
 132 const struct gdb_xml_element osdata_children[] = {
 133   { "item", NULL, item_children,
 134     GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
 135     osdata_start_item, NULL },
 136   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 137 };
 138
 139 const struct gdb_xml_element osdata_elements[] = {
 140   { "osdata", osdata_attributes, osdata_children,
 141     GDB_XML_EF_NONE, osdata_start_osdata, NULL },
 142   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 143 };
 144
 145 std::unique_ptr<osdata>
 146 osdata_parse (const char *xml)
 147 {
 148   osdata_parsing_data data;
 149
 150   if (gdb_xml_parse_quick (_("osdata"), "osdata.dtd",
 151                            osdata_elements, xml, &data) == 0)
 152     {
 153       /* Parsed successfully, don't need to delete the result.  */
 154       return std::move (data.osdata);
 155     }
 156
 157   return NULL;
 158 }
 159 #endif
 160
 161 std::unique_ptr<osdata>
 162 get_osdata (const char *type)
 163 {
 164   std::unique_ptr<osdata> osdata;
 165   gdb::optional<gdb::char_vector> xml = target_get_osdata (type);
 166
 167   if (xml)
 168     {
 169       if ((*xml)[0] == '\0')
 170         {
 171           if (type)
 172             warning (_("Empty data returned by target.  Wrong osdata type?"));
 173           else
 174             warning (_("Empty type list returned by target.  No type data?"));
 175         }
 176       else
 177         osdata = osdata_parse (xml->data ());
 178     }
 179
 180   if (osdata == NULL)
 181     error (_("Can not fetch data now."));
 182
 183   return osdata;
 184 }
 185
 186 const std::string *
 187 get_osdata_column (const osdata_item &item, const char *name)
 188 {
 189   for (const osdata_column &col : item.columns)
 190     if (col.name == name)
 191       return &col.value;
 192
 193   return NULL;
 194 }
 195
 196 void
 197 info_osdata (const char *type)
 198 {
 199   struct ui_out *uiout = current_uiout;
 200   struct osdata_item *last = NULL;
 201   int ncols = 0;
 202   int col_to_skip = -1;
 203
 204   if (type == NULL)
 205     type = "";
 206
 207   std::unique_ptr<osdata> osdata = get_osdata (type);
 208
 209   int nrows = osdata->items.size ();
 210
 211   if (*type == '\0' && nrows == 0)
 212     error (_("Available types of OS data not reported."));
 213
 214   if (!osdata->items.empty ())
 215     {
 216       last = &osdata->items.back ();
 217       ncols = last->columns.size ();
 218
 219       /* As a special case, scan the listing of available data types
 220          for a column named "Title", and only include it with MI
 221          output; this column's normal use is for titles for interface
 222          elements like menus, and it clutters up CLI output.  */
 223       if (*type == '\0' && !uiout->is_mi_like_p ())
 224         {
 225           for (int ix = 0; ix < last->columns.size (); ix++)
 226             {
 227               if (last->columns[ix].name == "Title")
 228                 col_to_skip = ix;
 229             }
 230           /* Be sure to reduce the total column count, otherwise
 231              internal errors ensue.  */
 232           if (col_to_skip >= 0)
 233             --ncols;
 234         }
 235     }
 236
 237   ui_out_emit_table table_emitter (uiout, ncols, nrows, "OSDataTable");
 238
 239   /* With no columns/items, we just output an empty table, but we
 240      still output the table.  This matters for MI.  */
 241   if (ncols == 0)
 242     return;
 243
 244   if (last != NULL && !last->columns.empty ())
 245     {
 246       for (int ix = 0; ix < last->columns.size (); ix++)
 247         {
 248           char col_name[32];
 249
 250           if (ix == col_to_skip)
 251             continue;
 252
 253           snprintf (col_name, 32, "col%d", ix);
 254           uiout->table_header (10, ui_left,
 255                                col_name, last->columns[ix].name.c_str ());
 256         }
 257     }
 258
 259   uiout->table_body ();
 260
 261   if (nrows != 0)
 262     {
 263       for (const osdata_item &item : osdata->items)
 264        {
 265          {
 266            ui_out_emit_tuple tuple_emitter (uiout, "item");
 267
 268            for (int ix_cols = 0; ix_cols < item.columns.size (); ix_cols++)
 269              {
 270                char col_name[32];
 271
 272                if (ix_cols == col_to_skip)
 273                  continue;
 274
 275                snprintf (col_name, 32, "col%d", ix_cols);
 276                uiout->field_string (col_name,
 277                                     item.columns[ix_cols].value.c_str ());
 278              }
 279          }
 280
 281          uiout->text ("\n");
 282        }
 283     }
 284 }
 285
 286 static void
 287 info_osdata_command (const char *arg, int from_tty)
 288 {
 289   info_osdata (arg);
 290 }
 291
 292 void _initialize_osdata ();
 293 void
 294 _initialize_osdata ()
 295 {
 296   add_info ("os", info_osdata_command,
 297            _("Show OS data ARG."));
 298 }