src/complain.c

   1 /* Declaration for error-reporting function for Bison.
   2
   3    Copyright (C) 2000-2002, 2004-2006, 2009-2013 Free Software
   4    Foundation, Inc.
   5
   6    This program is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation, either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 /* Based on error.c and error.h,
  20    written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
  21
  22 #include <config.h>
  23 #include "system.h"
  24
  25 #include <argmatch.h>
  26 #include <stdarg.h>
  27 #include <progname.h>
  28
  29 #include "complain.h"
  30 #include "files.h"
  31 #include "getargs.h"
  32 #include "quote.h"
  33
  34 err_status complaint_status = status_none;
  35
  36 bool warnings_are_errors = false;
  37
  38 /** Whether -Werror/-Wno-error was applied to a warning.  */
  39 typedef enum
  40   {
  41     errority_unset = 0,     /** No explict status.  */
  42     errority_disabled = 1,  /** Explictly disabled with -Wno-error=foo.  */
  43     errority_enabled = 2    /** Explictly enabled with -Werror=foo. */
  44   } errority;
  45
  46 /** For each warning type, its errority.  */
  47 static errority errority_flag[warnings_size];
  48
  49 /** Diagnostics severity.  */
  50 typedef enum
  51   {
  52     severity_disabled = 0, /**< Explicitly disabled via -Wno-foo.  */
  53     severity_unset = 1,    /**< Unspecified status.  */
  54     severity_warning = 2,  /**< A warning.  */
  55     severity_error = 3,    /**< An error (continue, but die soon).  */
  56     severity_fatal = 4     /**< Fatal error (die now).  */
  57   } severity;
  58
  59
  60 /** For each warning type, its severity.  */
  61 static severity warnings_flag[warnings_size];
  62
  63 static unsigned *indent_ptr = 0;
  64
  65 /*------------------------.
  66 | --warnings's handling.  |
  67 `------------------------*/
  68
  69 static const char * const warnings_args[] =
  70 {
  71   "none",
  72   "midrule-values",
  73   "yacc",
  74   "conflicts-sr",
  75   "conflicts-rr",
  76   "deprecated",
  77   "empty-rule",
  78   "precedence",
  79   "other",
  80   "all",
  81   "error",
  82   "everything",
  83   0
  84 };
  85
  86 static const int warnings_types[] =
  87 {
  88   Wnone,
  89   Wmidrule_values,
  90   Wyacc,
  91   Wconflicts_sr,
  92   Wconflicts_rr,
  93   Wdeprecated,
  94   Wempty_rule,
  95   Wprecedence,
  96   Wother,
  97   Wall,
  98   Werror,
  99   Weverything
 100 };
 101
 102 ARGMATCH_VERIFY (warnings_args, warnings_types);
 103
 104 void
 105 warning_argmatch (char const *arg, size_t no, size_t err)
 106 {
 107   int value = XARGMATCH ("--warning", arg + no + err,
 108                          warnings_args, warnings_types);
 109
 110   /* -Wnone == -Wno-everything, and -Wno-none == -Weverything.  */
 111   if (!value)
 112     {
 113       value = Weverything;
 114       no = !no;
 115     }
 116
 117   size_t b;
 118   for (b = 0; b < warnings_size; ++b)
 119     if (value & 1 << b)
 120       {
 121         if (err && no)
 122           /* -Wno-error=foo.  */
 123           errority_flag[b] = errority_disabled;
 124         else if (err && !no)
 125           {
 126             /* -Werror=foo: enables -Wfoo. */
 127             errority_flag[b] = errority_enabled;
 128             warnings_flag[b] = severity_warning;
 129           }
 130         else if (no)
 131           /* -Wno-foo.  */
 132           warnings_flag[b] = severity_disabled;
 133         else
 134           /* -Wfoo. */
 135           warnings_flag[b] = severity_warning;
 136       }
 137 }
 138
 139 /** Decode a comma-separated list of arguments from -W.
 140  *
 141  *  \param args     comma separated list of effective subarguments to decode.
 142  *                  If 0, then activate all the flags.
 143  */
 144
 145 void
 146 warnings_argmatch (char *args)
 147 {
 148   if (args)
 149     for (args = strtok (args, ","); args; args = strtok (NULL, ","))
 150       if (STREQ (args, "error"))
 151         warnings_are_errors = true;
 152       else if (STREQ (args, "no-error"))
 153         warnings_are_errors = false;
 154       else
 155         {
 156           // The length of the possible 'no-' prefix: 3, or 0.
 157           size_t no = STRPREFIX_LIT ("no-", args) ? 3 : 0;
 158           // The length of the possible 'error=' (possibly after
 159           // 'no-') prefix: 6, or 0.
 160           size_t err = STRPREFIX_LIT ("error=", args + no) ? 6 : 0;
 161
 162           warning_argmatch (args, no, err);
 163         }
 164   else
 165     warning_argmatch ("all", 0, 0);
 166 }
 167
 168
 169 /*-----------.
 170 | complain.  |
 171 `-----------*/
 172
 173 void
 174 complain_init (void)
 175 {
 176   warnings warnings_default =
 177     Wconflicts_sr | Wconflicts_rr | Wdeprecated | Wother;
 178
 179   size_t b;
 180   for (b = 0; b < warnings_size; ++b)
 181     {
 182       warnings_flag[b] = (1 << b & warnings_default
 183                           ? severity_warning
 184                           : severity_unset);
 185       errority_flag[b] = errority_unset;
 186     }
 187 }
 188
 189
 190 /* A diagnostic with FLAGS is about to be issued.  With what severity?
 191    (severity_fatal, severity_error, severity_disabled, or
 192    severity_warning.) */
 193
 194 static severity
 195 warning_severity (warnings flags)
 196 {
 197   if (flags & fatal)
 198     /* Diagnostics about fatal errors.  */
 199     return severity_fatal;
 200   else if (flags & complaint)
 201     /* Diagnostics about errors.  */
 202     return severity_error;
 203   else
 204     {
 205       /* Diagnostics about warnings.  */
 206       severity res = severity_disabled;
 207       size_t b;
 208       for (b = 0; b < warnings_size; ++b)
 209         if (flags & 1 << b)
 210           {
 211             res = res < warnings_flag[b] ? warnings_flag[b] : res;
 212             /* If the diagnostic is enabled, and -Werror is enabled,
 213                and -Wno-error=foo was not explicitly requested, this
 214                is an error. */
 215             if (res == severity_warning
 216                 && (errority_flag[b] == errority_enabled
 217                     || (warnings_are_errors
 218                         && errority_flag[b] != errority_disabled)))
 219               res = severity_error;
 220           }
 221       return res;
 222     }
 223 }
 224
 225 bool
 226 warning_is_unset (warnings flags)
 227 {
 228   size_t b;
 229   for (b = 0; b < warnings_size; ++b)
 230     if (flags & 1 << b && warnings_flag[b] != severity_unset)
 231       return false;
 232   return true;
 233 }
 234
 235 /** Display a "[-Wyacc]" like message on \a f.  */
 236
 237 static void
 238 warnings_print_categories (warnings warn_flags, FILE *f)
 239 {
 240   /* Display only the first match, the second is "-Wall".  */
 241   size_t i;
 242   for (i = 0; warnings_args[i]; ++i)
 243     if (warn_flags & warnings_types[i])
 244       {
 245         severity s = warning_severity (warnings_types[i]);
 246         fprintf (f, " [-W%s%s]",
 247                  s == severity_error ? "error=" : "",
 248                  warnings_args[i]);
 249         return;
 250       }
 251 }
 252
 253 /** Report an error message.
 254  *
 255  * \param loc     the location, defaulting to the current file,
 256  *                or the program name.
 257  * \param flags   the category for this message.
 258  * \param prefix  put before the message (e.g., "warning").
 259  * \param message the error message, a printf format string.  Iff it
 260  *                ends with ": ", then no trailing newline is printed,
 261  *                and the caller should print the remaining
 262  *                newline-terminated message to stderr.
 263  * \param args    the arguments of the format string.
 264  */
 265 static
 266 void
 267 error_message (const location *loc, warnings flags, const char *prefix,
 268                const char *message, va_list args)
 269 {
 270   unsigned pos = 0;
 271
 272   if (loc)
 273     pos += location_print (*loc, stderr);
 274   else
 275     pos += fprintf (stderr, "%s", current_file ? current_file : program_name);
 276   pos += fprintf (stderr, ": ");
 277
 278   if (indent_ptr)
 279     {
 280       if (*indent_ptr)
 281         prefix = NULL;
 282       if (!*indent_ptr)
 283         *indent_ptr = pos;
 284       else if (*indent_ptr > pos)
 285         fprintf (stderr, "%*s", *indent_ptr - pos, "");
 286       indent_ptr = 0;
 287     }
 288
 289   if (prefix)
 290     fprintf (stderr, "%s: ", prefix);
 291
 292   vfprintf (stderr, message, args);
 293   if (! (flags & silent))
 294     warnings_print_categories (flags, stderr);
 295   {
 296     size_t l = strlen (message);
 297     if (l < 2 || message[l - 2] != ':' || message[l - 1] != ' ')
 298       {
 299         putc ('\n', stderr);
 300         fflush (stderr);
 301         if (loc && feature_flag & feature_caret && !(flags & no_caret))
 302           location_caret (*loc, stderr);
 303       }
 304   }
 305   fflush (stderr);
 306 }
 307
 308 /** Raise a complaint. That can be a fatal error, an error or just a
 309     warning.  */
 310
 311 static void
 312 complains (const location *loc, warnings flags, const char *message,
 313            va_list args)
 314 {
 315   severity s = warning_severity (flags);
 316   if ((flags & complaint) && complaint_status < status_complaint)
 317     complaint_status = status_complaint;
 318
 319   if (severity_warning <= s)
 320     {
 321       const char* prefix =
 322         s == severity_fatal ? _("fatal error")
 323         : s == severity_error ? _("error")
 324         : _("warning");
 325       if (severity_error <= s && ! complaint_status)
 326         complaint_status = status_warning_as_error;
 327       error_message (loc, flags, prefix, message, args);
 328     }
 329
 330   if (flags & fatal)
 331     exit (EXIT_FAILURE);
 332 }
 333
 334 void
 335 complain (location const *loc, warnings flags, const char *message, ...)
 336 {
 337   va_list args;
 338   va_start (args, message);
 339   complains (loc, flags, message, args);
 340   va_end (args);
 341 }
 342
 343 void
 344 complain_indent (location const *loc, warnings flags, unsigned *indent,
 345                  const char *message, ...)
 346 {
 347   va_list args;
 348   indent_ptr = indent;
 349   va_start (args, message);
 350   complains (loc, flags, message, args);
 351   va_end (args);
 352 }
 353
 354 void
 355 complain_args (location const *loc, warnings w, unsigned *indent,
 356                int argc, char *argv[])
 357 {
 358   switch (argc)
 359   {
 360   case 1:
 361     complain_indent (loc, w, indent, "%s", _(argv[0]));
 362     break;
 363   case 2:
 364     complain_indent (loc, w, indent, _(argv[0]), argv[1]);
 365     break;
 366   case 3:
 367     complain_indent (loc, w, indent, _(argv[0]), argv[1], argv[2]);
 368     break;
 369   case 4:
 370     complain_indent (loc, w, indent, _(argv[0]), argv[1], argv[2], argv[3]);
 371     break;
 372   case 5:
 373     complain_indent (loc, w, indent, _(argv[0]), argv[1], argv[2], argv[3],
 374                      argv[4]);
 375     break;
 376   default:
 377     complain (loc, fatal, "too many arguments for complains");
 378     break;
 379   }
 380 }
 381
 382 void
 383 deprecated_directive (location const *loc, char const *old, char const *upd)
 384 {
 385   if (feature_flag & feature_caret)
 386     complain (loc, Wdeprecated,
 387               _("deprecated directive, use %s"),
 388               quote_n (1, upd));
 389   else
 390     complain (loc, Wdeprecated,
 391               _("deprecated directive: %s, use %s"),
 392               quote (old), quote_n (1, upd));
 393 }
 394
 395 void
 396 duplicate_directive (char const *directive,
 397                      location first, location second)
 398 {
 399   unsigned i = 0;
 400   complain (&second, complaint, _("only one %s allowed per rule"), directive);
 401   i += SUB_INDENT;
 402   complain_indent (&first, complaint, &i, _("previous declaration"));
 403 }