gdb/osdata.c

   1 /* Routines for handling XML generic OS data provided by target.
   2
   3    Copyright (C) 2008-2019 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 "common/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,
  60                         std::vector<gdb_xml_value> &attributes)
  61 {
  62   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  63
  64   if (data->osdata != NULL)
  65     gdb_xml_error (parser, _("Seen more than on osdata element"));
  66
  67   char *type = (char *) xml_find_attribute (attributes, "type")->value.get ();
  68   data->osdata.reset (new struct osdata (std::string (type)));
  69 }
  70
  71 /* Handle the start of a <item> element.  */
  72
  73 static void
  74 osdata_start_item (struct gdb_xml_parser *parser,
  75                   const struct gdb_xml_element *element,
  76                   void *user_data,
  77                   std::vector<gdb_xml_value> &attributes)
  78 {
  79   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  80   data->osdata->items.emplace_back ();
  81 }
  82
  83 /* Handle the start of a <column> element.  */
  84
  85 static void
  86 osdata_start_column (struct gdb_xml_parser *parser,
  87                     const struct gdb_xml_element *element,
  88                     void *user_data,
  89                     std::vector<gdb_xml_value> &attributes)
  90 {
  91   struct osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
  92   const char *name
  93     = (const char *) xml_find_attribute (attributes, "name")->value.get ();
  94
  95   data->property_name.assign (name);
  96 }
  97
  98 /* Handle the end of a <column> element.  */
  99
 100 static void
 101 osdata_end_column (struct gdb_xml_parser *parser,
 102                   const struct gdb_xml_element *element,
 103                   void *user_data, const char *body_text)
 104 {
 105   osdata_parsing_data *data = (struct osdata_parsing_data *) user_data;
 106   struct osdata *osdata = data->osdata.get ();
 107   osdata_item &item = osdata->items.back ();
 108
 109   item.columns.emplace_back (std::move (data->property_name),
 110                              std::string (body_text));
 111 }
 112
 113 /* The allowed elements and attributes for OS data object.
 114    The root element is a <osdata>.  */
 115
 116 const struct gdb_xml_attribute column_attributes[] = {
 117   { "name", GDB_XML_AF_NONE, NULL, NULL },
 118   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 119 };
 120
 121 const struct gdb_xml_element item_children[] = {
 122   { "column", column_attributes, NULL,
 123     GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
 124     osdata_start_column, osdata_end_column },
 125   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 126 };
 127
 128 const struct gdb_xml_attribute osdata_attributes[] = {
 129   { "type", GDB_XML_AF_NONE, NULL, NULL },
 130   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 131 };
 132
 133 const struct gdb_xml_element osdata_children[] = {
 134   { "item", NULL, item_children,
 135     GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
 136     osdata_start_item, NULL },
 137   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 138 };
 139
 140 const struct gdb_xml_element osdata_elements[] = {
 141   { "osdata", osdata_attributes, osdata_children,
 142     GDB_XML_EF_NONE, osdata_start_osdata, NULL },
 143   { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
 144 };
 145
 146 std::unique_ptr<osdata>
 147 osdata_parse (const char *xml)
 148 {
 149   osdata_parsing_data data;
 150
 151   if (gdb_xml_parse_quick (_("osdata"), "osdata.dtd",
 152                            osdata_elements, xml, &data) == 0)
 153     {
 154       /* Parsed successfully, don't need to delete the result.  */
 155       return std::move (data.osdata);
 156     }
 157
 158   return NULL;
 159 }
 160 #endif
 161
 162 std::unique_ptr<osdata>
 163 get_osdata (const char *type)
 164 {
 165   std::unique_ptr<osdata> osdata;
 166   gdb::optional<gdb::char_vector> xml = target_get_osdata (type);
 167
 168   if (xml)
 169     {
 170       if ((*xml)[0] == '\0')
 171         {
 172           if (type)
 173             warning (_("Empty data returned by target.  Wrong osdata type?"));
 174           else
 175             warning (_("Empty type list returned by target.  No type data?"));
 176         }
 177       else
 178         osdata = osdata_parse (xml->data ());
 179     }
 180
 181   if (osdata == NULL)
 182     error (_("Can not fetch data now."));
 183
 184   return osdata;
 185 }
 186
 187 const std::string *
 188 get_osdata_column (const osdata_item &item, const char *name)
 189 {
 190   for (const osdata_column &col : item.columns)
 191     if (col.name == name)
 192       return &col.value;
 193
 194   return NULL;
 195 }
 196
 197 void
 198 info_osdata (const char *type)
 199 {
 200   struct ui_out *uiout = current_uiout;
 201   struct osdata_item *last = NULL;
 202   int ncols = 0;
 203   int col_to_skip = -1;
 204
 205   if (type == NULL)
 206     type = "";
 207
 208   std::unique_ptr<osdata> osdata = get_osdata (type);
 209
 210   int nrows = osdata->items.size ();
 211
 212   if (*type == '\0' && nrows == 0)
 213     error (_("Available types of OS data not reported."));
 214
 215   if (!osdata->items.empty ())
 216     {
 217       last = &osdata->items.back ();
 218       ncols = last->columns.size ();
 219
 220       /* As a special case, scan the listing of available data types
 221          for a column named "Title", and only include it with MI
 222          output; this column's normal use is for titles for interface
 223          elements like menus, and it clutters up CLI output.  */
 224       if (*type == '\0' && !uiout->is_mi_like_p ())
 225         {
 226           for (int ix = 0; ix < last->columns.size (); ix++)
 227             {
 228               if (last->columns[ix].name == "Title")
 229                 col_to_skip = ix;
 230             }
 231           /* Be sure to reduce the total column count, otherwise
 232              internal errors ensue.  */
 233           if (col_to_skip >= 0)
 234             --ncols;
 235         }
 236     }
 237
 238   ui_out_emit_table table_emitter (uiout, ncols, nrows, "OSDataTable");
 239
 240   /* With no columns/items, we just output an empty table, but we
 241      still output the table.  This matters for MI.  */
 242   if (ncols == 0)
 243     return;
 244
 245   if (last != NULL && !last->columns.empty ())
 246     {
 247       for (int ix = 0; ix < last->columns.size (); ix++)
 248         {
 249           char col_name[32];
 250
 251           if (ix == col_to_skip)
 252             continue;
 253
 254           snprintf (col_name, 32, "col%d", ix);
 255           uiout->table_header (10, ui_left,
 256                                col_name, last->columns[ix].name.c_str ());
 257         }
 258     }
 259
 260   uiout->table_body ();
 261
 262   if (nrows != 0)
 263     {
 264       for (const osdata_item &item : osdata->items)
 265        {
 266          {
 267            ui_out_emit_tuple tuple_emitter (uiout, "item");
 268
 269            for (int ix_cols = 0; ix_cols < item.columns.size (); ix_cols++)
 270              {
 271                char col_name[32];
 272
 273                if (ix_cols == col_to_skip)
 274                  continue;
 275
 276                snprintf (col_name, 32, "col%d", ix_cols);
 277                uiout->field_string (col_name,
 278                                     item.columns[ix_cols].value.c_str ());
 279              }
 280          }
 281
 282          uiout->text ("\n");
 283        }
 284     }
 285 }
 286
 287 static void
 288 info_osdata_command (const char *arg, int from_tty)
 289 {
 290   info_osdata (arg);
 291 }
 292
 293 void
 294 _initialize_osdata (void)
 295 {
 296   add_info ("os", info_osdata_command,
 297            _("Show OS data ARG."));
 298 }