gdb/complaints.c

   1 /* Support for complaint handling during symbol reading in GDB.
   2
   3    Copyright (C) 1990-2017 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 "complaints.h"
  22 #include "command.h"
  23 #include "gdbcmd.h"
  24
  25 /* Should each complaint message be self explanatory, or should we
  26    assume that a series of complaints is being produced?  */
  27
  28 enum complaint_series {
  29   /* Isolated self explanatory message.  */
  30   ISOLATED_MESSAGE,
  31
  32   /* First message of a series, includes an explanation.  */
  33   FIRST_MESSAGE,
  34
  35   /* First message of a series, but does not need to include any sort
  36      of explanation.  */
  37   SHORT_FIRST_MESSAGE,
  38
  39   /* Subsequent message of a series that needs no explanation (the
  40      user already knows we have a problem so we can just state our
  41      piece).  */
  42   SUBSEQUENT_MESSAGE
  43 };
  44
  45 /* Structure to manage complaints about symbol file contents.  */
  46
  47 struct complain
  48 {
  49   const char *file;
  50   int line;
  51   const char *fmt;
  52   int counter;
  53   struct complain *next;
  54 };
  55
  56 /* The explanatory message that should accompany the complaint.  The
  57    message is in two parts - pre and post - that are printed around
  58    the complaint text.  */
  59 struct explanation
  60 {
  61   const char *prefix;
  62   const char *postfix;
  63 };
  64
  65 struct complaints
  66 {
  67   struct complain *root;
  68
  69   enum complaint_series series;
  70
  71   /* The explanatory messages that should accompany the complaint.
  72      NOTE: cagney/2002-08-14: In a desperate attempt at being vaguely
  73      i18n friendly, this is an array of two messages.  When present,
  74      the PRE and POST EXPLANATION[SERIES] are used to wrap the
  75      message.  */
  76   const struct explanation *explanation;
  77 };
  78
  79 static struct complain complaint_sentinel;
  80
  81 /* The symbol table complaint table.  */
  82
  83 static struct explanation symfile_explanations[] = {
  84   { "During symbol reading, ", "." },
  85   { "During symbol reading...", "..."},
  86   { "", "..."},
  87   { "", "..."},
  88   { NULL, NULL }
  89 };
  90
  91 static struct complaints symfile_complaint_book = {
  92   &complaint_sentinel,
  93   ISOLATED_MESSAGE,
  94   symfile_explanations
  95 };
  96 struct complaints *symfile_complaints = &symfile_complaint_book;
  97
  98 /* Wrapper function to, on-demand, fill in a complaints object.  */
  99
 100 static struct complaints *
 101 get_complaints (struct complaints **c)
 102 {
 103   if ((*c) != NULL)
 104     return (*c);
 105   (*c) = XNEW (struct complaints);
 106   (*c)->root = &complaint_sentinel;
 107   (*c)->series = ISOLATED_MESSAGE;
 108   (*c)->explanation = NULL;
 109   return (*c);
 110 }
 111
 112 static struct complain * ATTRIBUTE_PRINTF (4, 0)
 113 find_complaint (struct complaints *complaints, const char *file,
 114                 int line, const char *fmt)
 115 {
 116   struct complain *complaint;
 117
 118   /* Find the complaint in the table.  A more efficient search
 119      algorithm (based on hash table or something) could be used.  But
 120      that can wait until someone shows evidence that this lookup is
 121      a real bottle neck.  */
 122   for (complaint = complaints->root;
 123        complaint != NULL;
 124        complaint = complaint->next)
 125     {
 126       if (complaint->fmt == fmt
 127           && complaint->file == file
 128           && complaint->line == line)
 129         return complaint;
 130     }
 131
 132   /* Oops not seen before, fill in a new complaint.  */
 133   complaint = XNEW (struct complain);
 134   complaint->fmt = fmt;
 135   complaint->file = file;
 136   complaint->line = line;
 137   complaint->counter = 0;
 138   complaint->next = NULL;
 139
 140   /* File it, return it.  */
 141   complaint->next = complaints->root;
 142   complaints->root = complaint;
 143   return complaint;
 144 }
 145
 146
 147 /* How many complaints about a particular thing should be printed
 148    before we stop whining about it?  Default is no whining at all,
 149    since so many systems have ill-constructed symbol files.  */
 150
 151 int stop_whining = 0;
 152
 153 /* Print a complaint, and link the complaint block into a chain for
 154    later handling.  */
 155
 156 static void ATTRIBUTE_PRINTF (4, 0)
 157 vcomplaint (struct complaints **c, const char *file,
 158             int line, const char *fmt,
 159             va_list args)
 160 {
 161   struct complaints *complaints = get_complaints (c);
 162   struct complain *complaint = find_complaint (complaints, file,
 163                                                line, fmt);
 164   enum complaint_series series;
 165
 166   gdb_assert (complaints != NULL);
 167
 168   complaint->counter++;
 169   if (complaint->counter > stop_whining)
 170     return;
 171
 172   if (info_verbose)
 173     series = SUBSEQUENT_MESSAGE;
 174   else
 175     series = complaints->series;
 176
 177   /* Pass 'fmt' instead of 'complaint->fmt' to printf-like callees
 178      from here on, to avoid "format string is not a string literal"
 179      warnings.  'fmt' is this function's printf-format parameter, so
 180      the compiler can assume the passed in argument is a literal
 181      string somewhere up the call chain.  */
 182   gdb_assert (complaint->fmt == fmt);
 183
 184   if (complaint->file != NULL)
 185     internal_vwarning (complaint->file, complaint->line, fmt, args);
 186   else if (deprecated_warning_hook)
 187     (*deprecated_warning_hook) (fmt, args);
 188   else
 189     {
 190       if (complaints->explanation == NULL)
 191         /* A [v]warning() call always appends a newline.  */
 192         vwarning (fmt, args);
 193       else
 194         {
 195           std::string msg = string_vprintf (fmt, args);
 196           wrap_here ("");
 197           if (series != SUBSEQUENT_MESSAGE)
 198             begin_line ();
 199           /* XXX: i18n */
 200           fprintf_filtered (gdb_stderr, "%s%s%s",
 201                             complaints->explanation[series].prefix,
 202                             msg.c_str (),
 203                             complaints->explanation[series].postfix);
 204           /* Force a line-break after any isolated message.  For the
 205              other cases, clear_complaints() takes care of any missing
 206              trailing newline, the wrap_here() is just a hint.  */
 207           if (series == ISOLATED_MESSAGE)
 208             /* It would be really nice to use begin_line() here.
 209                Unfortunately that function doesn't track GDB_STDERR and
 210                consequently will sometimes supress a line when it
 211                shouldn't.  */
 212             fputs_filtered ("\n", gdb_stderr);
 213           else
 214             wrap_here ("");
 215         }
 216     }
 217
 218   switch (series)
 219     {
 220     case ISOLATED_MESSAGE:
 221       break;
 222     case FIRST_MESSAGE:
 223       complaints->series = SUBSEQUENT_MESSAGE;
 224       break;
 225     case SUBSEQUENT_MESSAGE:
 226     case SHORT_FIRST_MESSAGE:
 227       complaints->series = SUBSEQUENT_MESSAGE;
 228       break;
 229     }
 230
 231   /* If GDB dumps core, we'd like to see the complaints first.
 232      Presumably GDB will not be sending so many complaints that this
 233      becomes a performance hog.  */
 234
 235   gdb_flush (gdb_stderr);
 236 }
 237
 238 void
 239 complaint_internal (struct complaints **complaints, const char *fmt, ...)
 240 {
 241   va_list args;
 242
 243   va_start (args, fmt);
 244   vcomplaint (complaints, NULL/*file*/, 0/*line*/, fmt, args);
 245   va_end (args);
 246 }
 247
 248 void
 249 internal_complaint (struct complaints **complaints, const char *file,
 250                     int line, const char *fmt, ...)
 251 {
 252   va_list args;
 253   va_start (args, fmt);
 254   vcomplaint (complaints, file, line, fmt, args);
 255   va_end (args);
 256 }
 257
 258 /* Clear out / initialize all complaint counters that have ever been
 259    incremented.  If LESS_VERBOSE is 1, be less verbose about
 260    successive complaints, since the messages are appearing all
 261    together during a command that is reporting a contiguous block of
 262    complaints (rather than being interleaved with other messages).  If
 263    noisy is 1, we are in a noisy command, and our caller will print
 264    enough context for the user to figure it out.  */
 265
 266 void
 267 clear_complaints (struct complaints **c, int less_verbose, int noisy)
 268 {
 269   struct complaints *complaints = get_complaints (c);
 270   struct complain *p;
 271
 272   for (p = complaints->root; p != NULL; p = p->next)
 273     {
 274       p->counter = 0;
 275     }
 276
 277   switch (complaints->series)
 278     {
 279     case FIRST_MESSAGE:
 280       /* Haven't yet printed anything.  */
 281       break;
 282     case SHORT_FIRST_MESSAGE:
 283       /* Haven't yet printed anything.  */
 284       break;
 285     case ISOLATED_MESSAGE:
 286       /* The code above, always forces a line-break.  No need to do it
 287          here.  */
 288       break;
 289     case SUBSEQUENT_MESSAGE:
 290       /* It would be really nice to use begin_line() here.
 291          Unfortunately that function doesn't track GDB_STDERR and
 292          consequently will sometimes supress a line when it
 293          shouldn't.  */
 294       fputs_unfiltered ("\n", gdb_stderr);
 295       break;
 296     default:
 297       internal_error (__FILE__, __LINE__, _("bad switch"));
 298     }
 299
 300   if (!less_verbose)
 301     complaints->series = ISOLATED_MESSAGE;
 302   else if (!noisy)
 303     complaints->series = FIRST_MESSAGE;
 304   else
 305     complaints->series = SHORT_FIRST_MESSAGE;
 306 }
 307
 308 static void
 309 complaints_show_value (struct ui_file *file, int from_tty,
 310                        struct cmd_list_element *cmd, const char *value)
 311 {
 312   fprintf_filtered (file, _("Max number of complaints about incorrect"
 313                             " symbols is %s.\n"),
 314                     value);
 315 }
 316
 317 void
 318 _initialize_complaints (void)
 319 {
 320   add_setshow_zinteger_cmd ("complaints", class_support,
 321                             &stop_whining, _("\
 322 Set max number of complaints about incorrect symbols."), _("\
 323 Show max number of complaints about incorrect symbols."), NULL,
 324                             NULL, complaints_show_value,
 325                             &setlist, &showlist);
 326 }