libcc1/libcp1.cc

   1 /* The library used by gdb.
   2    Copyright (C) 2014-2021 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #include <cc1plugin-config.h>
  21 #include <vector>
  22 #include <string>
  23 #include <sys/socket.h>
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26 #include <sys/wait.h>
  27 #include <stdio.h>
  28 #include <errno.h>
  29 #include <sys/stat.h>
  30 #include <stdlib.h>
  31 #include <sstream>
  32 #include "marshall-cp.hh"
  33 #include "rpc.hh"
  34 #include "connection.hh"
  35 #include "names.hh"
  36 #include "callbacks.hh"
  37 #include "libiberty.h"
  38 #include "xregex.h"
  39 #include "findcomp.hh"
  40 #include "compiler-name.hh"
  41 #include "intl.h"
  42
  43 struct libcp1;
  44
  45 class libcp1_connection;
  46
  47 // The C compiler context that we hand back to our caller.
  48 struct libcp1 : public gcc_cp_context
  49 {
  50   libcp1 (const gcc_base_vtable *, const gcc_cp_fe_vtable *);
  51
  52   // A convenience function to print something.
  53   void print (const char *str)
  54   {
  55     this->print_function (this->print_datum, str);
  56   }
  57
  58   std::unique_ptr<libcp1_connection> connection;
  59
  60   gcc_cp_oracle_function *binding_oracle;
  61   gcc_cp_symbol_address_function *address_oracle;
  62   gcc_cp_enter_leave_user_expr_scope_function *enter_scope;
  63   gcc_cp_enter_leave_user_expr_scope_function *leave_scope;
  64   void *oracle_datum;
  65
  66   void (*print_function) (void *datum, const char *message);
  67   void *print_datum;
  68
  69   std::vector<std::string> args;
  70   std::string source_file;
  71
  72   /* Non-zero as an equivalent to gcc driver option "-v".  */
  73   bool verbose;
  74
  75   /* Compiler to set by set_triplet_regexp or set_driver_filename.  */
  76   class compiler
  77   {
  78   protected:
  79     libcp1 *self_;
  80   public:
  81     compiler (libcp1 *self) : self_ (self)
  82     {
  83     }
  84     virtual char *find (std::string &compiler) const;
  85     virtual ~compiler ()
  86     {
  87     }
  88   };
  89
  90   std::unique_ptr<compiler> compilerp;
  91
  92   /* Compiler to set by set_triplet_regexp.  */
  93   class compiler_triplet_regexp : public compiler
  94   {
  95   private:
  96     std::string triplet_regexp_;
  97   public:
  98     char *find (std::string &compiler) const override;
  99     compiler_triplet_regexp (libcp1 *self, std::string triplet_regexp)
 100       : compiler (self), triplet_regexp_ (triplet_regexp)
 101     {
 102     }
 103     virtual ~compiler_triplet_regexp ()
 104     {
 105     }
 106   };
 107
 108   /* Compiler to set by set_driver_filename.  */
 109   class compiler_driver_filename : public compiler
 110   {
 111   private:
 112     std::string driver_filename_;
 113   public:
 114     char *find (std::string &compiler) const override;
 115     compiler_driver_filename (libcp1 *self, std::string driver_filename)
 116       : compiler (self), driver_filename_ (driver_filename)
 117     {
 118     }
 119     virtual ~compiler_driver_filename ()
 120     {
 121     }
 122   };
 123 };
 124
 125 // A local subclass of connection that holds a back-pointer to the
 126 // gcc_c_context object that we provide to our caller.
 127 class libcp1_connection : public cc1_plugin::connection
 128 {
 129 public:
 130
 131   libcp1_connection (int fd, int aux_fd, libcp1 *b)
 132     : connection (fd, aux_fd),
 133       back_ptr (b)
 134   {
 135   }
 136
 137   void print (const char *buf) override
 138   {
 139     back_ptr->print (buf);
 140   }
 141
 142   libcp1 *back_ptr;
 143 };
 144
 145 libcp1::libcp1 (const gcc_base_vtable *v,
 146                   const gcc_cp_fe_vtable *cv)
 147   : binding_oracle (NULL),
 148     address_oracle (NULL),
 149     oracle_datum (NULL),
 150     print_function (NULL),
 151     print_datum (NULL),
 152     args (),
 153     source_file (),
 154     verbose (false),
 155     compilerp (new libcp1::compiler (this))
 156 {
 157   base.ops = v;
 158   cp_ops = cv;
 159 }
 160
 161 \f
 162
 163 // Enclose these functions in an anonymous namespace because they
 164 // shouldn't be exported, but they can't be static because they're
 165 // used as template arguments.
 166 namespace {
 167   // This is a wrapper function that is called by the RPC system and
 168   // that then forwards the call to the library user.  Note that the
 169   // return value is not used; the type cannot be 'void' due to
 170   // limitations in our simple RPC.
 171   int
 172   cp_call_binding_oracle (cc1_plugin::connection *conn,
 173                        enum gcc_cp_oracle_request request,
 174                        const char *identifier)
 175   {
 176     libcp1 *self = ((libcp1_connection *) conn)->back_ptr;
 177
 178     self->binding_oracle (self->oracle_datum, self, request, identifier);
 179     return 1;
 180   }
 181
 182   // This is a wrapper function that is called by the RPC system and
 183   // that then forwards the call to the library user.
 184   gcc_address
 185   cp_call_symbol_address (cc1_plugin::connection *conn, const char *identifier)
 186   {
 187     libcp1 *self = ((libcp1_connection *) conn)->back_ptr;
 188
 189     return self->address_oracle (self->oracle_datum, self, identifier);
 190   }
 191
 192   int
 193   cp_call_enter_scope (cc1_plugin::connection *conn)
 194   {
 195     libcp1 *self = ((libcp1_connection *) conn)->back_ptr;
 196
 197     self->enter_scope (self->oracle_datum, self);
 198     return 1;
 199   }
 200
 201   int
 202   cp_call_leave_scope (cc1_plugin::connection *conn)
 203   {
 204     libcp1 *self = ((libcp1_connection *) conn)->back_ptr;
 205
 206     self->leave_scope (self->oracle_datum, self);
 207     return 1;
 208   }
 209 } /* anonymous namespace */
 210
 211 \f
 212
 213 static void
 214 set_callbacks (struct gcc_cp_context *s,
 215                gcc_cp_oracle_function *binding_oracle,
 216                gcc_cp_symbol_address_function *address_oracle,
 217                gcc_cp_enter_leave_user_expr_scope_function *enter_scope,
 218                gcc_cp_enter_leave_user_expr_scope_function *leave_scope,
 219                void *datum)
 220 {
 221   libcp1 *self = (libcp1 *) s;
 222
 223   self->binding_oracle = binding_oracle;
 224   self->address_oracle = address_oracle;
 225   self->enter_scope = enter_scope;
 226   self->leave_scope = leave_scope;
 227   self->oracle_datum = datum;
 228 }
 229
 230 // Instances of this rpc<> template function are installed into the
 231 // "cp_vtable".  These functions are parameterized by type and method
 232 // name and forward the call via the connection.
 233
 234 template<typename R, const char *&NAME, typename... Arg>
 235 R rpc (struct gcc_cp_context *s, Arg... rest)
 236 {
 237   libcp1 *self = (libcp1 *) s;
 238   R result;
 239
 240   if (!cc1_plugin::call (self->connection.get (), NAME, &result, rest...))
 241     return 0;
 242   return result;
 243 }
 244
 245 static const struct gcc_cp_fe_vtable cp_vtable =
 246 {
 247   GCC_CP_FE_VERSION_0,
 248   set_callbacks,
 249
 250 #define GCC_METHOD0(R, N) \
 251   rpc<R, cc1_plugin::cp::N>,
 252 #define GCC_METHOD1(R, N, A) \
 253   rpc<R, cc1_plugin::cp::N, A>,
 254 #define GCC_METHOD2(R, N, A, B) \
 255   rpc<R, cc1_plugin::cp::N, A, B>,
 256 #define GCC_METHOD3(R, N, A, B, C) \
 257   rpc<R, cc1_plugin::cp::N, A, B, C>,
 258 #define GCC_METHOD4(R, N, A, B, C, D) \
 259   rpc<R, cc1_plugin::cp::N, A, B, C, D>,
 260 #define GCC_METHOD5(R, N, A, B, C, D, E) \
 261   rpc<R, cc1_plugin::cp::N, A, B, C, D, E>,
 262 #define GCC_METHOD7(R, N, A, B, C, D, E, F, G) \
 263   rpc<R, cc1_plugin::cp::N, A, B, C, D, E, F, G>,
 264
 265 #include "gcc-cp-fe.def"
 266
 267 #undef GCC_METHOD0
 268 #undef GCC_METHOD1
 269 #undef GCC_METHOD2
 270 #undef GCC_METHOD3
 271 #undef GCC_METHOD4
 272 #undef GCC_METHOD5
 273 #undef GCC_METHOD7
 274 };
 275
 276 \f
 277
 278 // Construct an appropriate regexp to match the compiler name.
 279 static std::string
 280 make_regexp (const char *triplet_regexp, const char *compiler)
 281 {
 282   std::stringstream buf;
 283
 284   buf << "^" << triplet_regexp << "-";
 285
 286   // Quote the compiler name in case it has something funny in it.
 287   for (const char *p = compiler; *p; ++p)
 288     {
 289       switch (*p)
 290         {
 291         case '.':
 292         case '^':
 293         case '$':
 294         case '*':
 295         case '+':
 296         case '?':
 297         case '(':
 298         case ')':
 299         case '[':
 300         case '{':
 301         case '\\':
 302         case '|':
 303           buf << '\\';
 304           break;
 305         }
 306       buf << *p;
 307     }
 308   buf << "$";
 309
 310   return buf.str ();
 311 }
 312
 313 static void
 314 libcp1_set_verbose (struct gcc_base_context *s, int /* bool */ verbose)
 315 {
 316   libcp1 *self = (libcp1 *) s;
 317
 318   self->verbose = verbose != 0;
 319 }
 320
 321 char *
 322 libcp1::compiler::find (std::string &compiler ATTRIBUTE_UNUSED) const
 323 {
 324   return xstrdup (_("Compiler has not been specified"));
 325 }
 326
 327 char *
 328 libcp1::compiler_triplet_regexp::find (std::string &compiler) const
 329 {
 330   std::string rx = make_regexp (triplet_regexp_.c_str (), CP_COMPILER_NAME);
 331   if (self_->verbose)
 332     fprintf (stderr, _("searching for compiler matching regex %s\n"),
 333              rx.c_str());
 334   regex_t triplet;
 335   int code = regcomp (&triplet, rx.c_str (), REG_EXTENDED | REG_NOSUB);
 336   if (code != 0)
 337     {
 338       size_t len = regerror (code, &triplet, NULL, 0);
 339       char err[len];
 340
 341       regerror (code, &triplet, err, len);
 342
 343       return concat ("Could not compile regexp \"",
 344                      rx.c_str (),
 345                      "\": ",
 346                      err,
 347                      (char *) NULL);
 348     }
 349
 350   if (!find_compiler (triplet, &compiler))
 351     {
 352       regfree (&triplet);
 353       return concat ("Could not find a compiler matching \"",
 354                      rx.c_str (),
 355                      "\"",
 356                      (char *) NULL);
 357     }
 358   regfree (&triplet);
 359   if (self_->verbose)
 360     fprintf (stderr, _("found compiler %s\n"), compiler.c_str());
 361   return NULL;
 362 }
 363
 364 char *
 365 libcp1::compiler_driver_filename::find (std::string &compiler) const
 366 {
 367   // Simulate fnotice by fprintf.
 368   if (self_->verbose)
 369     fprintf (stderr, _("using explicit compiler filename %s\n"),
 370              driver_filename_.c_str());
 371   compiler = driver_filename_;
 372   return NULL;
 373 }
 374
 375 static char *
 376 libcp1_set_arguments (struct gcc_base_context *s,
 377                       int argc, char **argv)
 378 {
 379   libcp1 *self = (libcp1 *) s;
 380
 381   std::string compiler;
 382   char *errmsg = self->compilerp->find (compiler);
 383   if (errmsg != NULL)
 384     return errmsg;
 385
 386   self->args.push_back (compiler);
 387
 388   for (int i = 0; i < argc; ++i)
 389     self->args.push_back (argv[i]);
 390
 391   return NULL;
 392 }
 393
 394 static char *
 395 libcp1_set_triplet_regexp (struct gcc_base_context *s,
 396                            const char *triplet_regexp)
 397 {
 398   libcp1 *self = (libcp1 *) s;
 399
 400   self->compilerp.reset (new libcp1::compiler_triplet_regexp (self,
 401                                                               triplet_regexp));
 402   return NULL;
 403 }
 404
 405 static char *
 406 libcp1_set_driver_filename (struct gcc_base_context *s,
 407                             const char *driver_filename)
 408 {
 409   libcp1 *self = (libcp1 *) s;
 410
 411   self->compilerp.reset (new libcp1::compiler_driver_filename (self,
 412                                                                driver_filename));
 413   return NULL;
 414 }
 415
 416 static char *
 417 libcp1_set_arguments_v0 (struct gcc_base_context *s,
 418                          const char *triplet_regexp,
 419                          int argc, char **argv)
 420 {
 421   char *errmsg = libcp1_set_triplet_regexp (s, triplet_regexp);
 422   if (errmsg != NULL)
 423     return errmsg;
 424
 425   return libcp1_set_arguments (s, argc, argv);
 426 }
 427
 428 static void
 429 libcp1_set_source_file (struct gcc_base_context *s,
 430                          const char *file)
 431 {
 432   libcp1 *self = (libcp1 *) s;
 433
 434   self->source_file = file;
 435 }
 436
 437 static void
 438 libcp1_set_print_callback (struct gcc_base_context *s,
 439                             void (*print_function) (void *datum,
 440                                                     const char *message),
 441                             void *datum)
 442 {
 443   libcp1 *self = (libcp1 *) s;
 444
 445   self->print_function = print_function;
 446   self->print_datum = datum;
 447 }
 448
 449 static int
 450 fork_exec (libcp1 *self, char **argv, int spair_fds[2], int stderr_fds[2])
 451 {
 452   pid_t child_pid = fork ();
 453
 454   if (child_pid == -1)
 455     {
 456       close (spair_fds[0]);
 457       close (spair_fds[1]);
 458       close (stderr_fds[0]);
 459       close (stderr_fds[1]);
 460       return 0;
 461     }
 462
 463   if (child_pid == 0)
 464     {
 465       // Child.
 466       dup2 (stderr_fds[1], 1);
 467       dup2 (stderr_fds[1], 2);
 468       close (stderr_fds[0]);
 469       close (stderr_fds[1]);
 470       close (spair_fds[0]);
 471
 472       execvp (argv[0], argv);
 473       _exit (127);
 474     }
 475   else
 476     {
 477       // Parent.
 478       close (spair_fds[1]);
 479       close (stderr_fds[1]);
 480
 481       cc1_plugin::status result = cc1_plugin::FAIL;
 482       if (self->connection->send ('H')
 483           && ::cc1_plugin::marshall (self->connection.get (),
 484                                      GCC_CP_FE_VERSION_0))
 485         result = self->connection->wait_for_query ();
 486
 487       close (spair_fds[0]);
 488       close (stderr_fds[0]);
 489
 490       while (true)
 491         {
 492           int status;
 493
 494           if (waitpid (child_pid, &status, 0) == -1)
 495             {
 496               if (errno != EINTR)
 497                 return 0;
 498             }
 499
 500           if (!WIFEXITED (status) || WEXITSTATUS (status) != 0)
 501             return 0;
 502           break;
 503         }
 504
 505       if (!result)
 506         return 0;
 507       return 1;
 508     }
 509 }
 510
 511 static int
 512 libcp1_compile (struct gcc_base_context *s,
 513                 const char *filename)
 514 {
 515   libcp1 *self = (libcp1 *) s;
 516
 517   int fds[2];
 518   if (socketpair (AF_UNIX, SOCK_STREAM, 0, fds) != 0)
 519     {
 520       self->print ("could not create socketpair\n");
 521       return 0;
 522     }
 523
 524   int stderr_fds[2];
 525   if (pipe (stderr_fds) != 0)
 526     {
 527       self->print ("could not create pipe\n");
 528       close (fds[0]);
 529       close (fds[1]);
 530       return 0;
 531     }
 532
 533   self->args.push_back ("-fplugin=libcp1plugin");
 534   char buf[100];
 535   if (snprintf (buf, sizeof (buf), "-fplugin-arg-libcp1plugin-fd=%d", fds[1])
 536       >= (long) sizeof (buf))
 537     abort ();
 538   self->args.push_back (buf);
 539
 540   self->args.push_back (self->source_file);
 541   self->args.push_back ("-c");
 542   self->args.push_back ("-o");
 543   self->args.push_back (filename);
 544   if (self->verbose)
 545     self->args.push_back ("-v");
 546
 547   self->connection.reset (new libcp1_connection (fds[0], stderr_fds[0], self));
 548
 549   cc1_plugin::callback_ftype *fun
 550     = cc1_plugin::callback<int,
 551                            enum gcc_cp_oracle_request,
 552                            const char *,
 553                            cp_call_binding_oracle>;
 554   self->connection->add_callback ("binding_oracle", fun);
 555
 556   fun = cc1_plugin::callback<gcc_address,
 557                              const char *,
 558                              cp_call_symbol_address>;
 559   self->connection->add_callback ("address_oracle", fun);
 560
 561   fun = cc1_plugin::callback<int,
 562                              cp_call_enter_scope>;
 563   self->connection->add_callback ("enter_scope", fun);
 564
 565   fun = cc1_plugin::callback<int,
 566                              cp_call_leave_scope>;
 567   self->connection->add_callback ("leave_scope", fun);
 568
 569   char **argv = new (std::nothrow) char *[self->args.size () + 1];
 570   if (argv == NULL)
 571     return 0;
 572
 573   for (unsigned int i = 0; i < self->args.size (); ++i)
 574     argv[i] = const_cast<char *> (self->args[i].c_str ());
 575   argv[self->args.size ()] = NULL;
 576
 577   return fork_exec (self, argv, fds, stderr_fds);
 578 }
 579
 580 static int
 581 libcp1_compile_v0 (struct gcc_base_context *s, const char *filename,
 582                    int verbose)
 583 {
 584   libcp1_set_verbose (s, verbose);
 585   return libcp1_compile (s, filename);
 586 }
 587
 588 static void
 589 libcp1_destroy (struct gcc_base_context *s)
 590 {
 591   libcp1 *self = (libcp1 *) s;
 592
 593   delete self;
 594 }
 595
 596 static const struct gcc_base_vtable vtable =
 597 {
 598   GCC_FE_VERSION_0,
 599   libcp1_set_arguments_v0,
 600   libcp1_set_source_file,
 601   libcp1_set_print_callback,
 602   libcp1_compile_v0,
 603   libcp1_destroy,
 604   libcp1_set_verbose,
 605   libcp1_compile,
 606   libcp1_set_arguments,
 607   libcp1_set_triplet_regexp,
 608   libcp1_set_driver_filename,
 609 };
 610
 611 extern "C" gcc_cp_fe_context_function gcc_cp_fe_context;
 612
 613 #ifdef __GNUC__
 614 #pragma GCC visibility push(default)
 615 #endif
 616
 617 extern "C"
 618 struct gcc_cp_context *
 619 gcc_cp_fe_context (enum gcc_base_api_version base_version,
 620                     enum gcc_cp_api_version cp_version)
 621 {
 622   if ((base_version != GCC_FE_VERSION_0 && base_version != GCC_FE_VERSION_1)
 623       || cp_version != GCC_CP_FE_VERSION_0)
 624     return NULL;
 625
 626   return new libcp1 (&vtable, &cp_vtable);
 627 }