gcc/gcov-io.c

   1 /* File format for coverage information
   2    Copyright (C) 1996, 1997, 1998, 2000, 2002, 2003, 2004, 2005, 2007
   3    Free Software Foundation, Inc.
   4    Contributed by Bob Manson <manson@cygnus.com>.
   5    Completely remangled by Nathan Sidwell <nathan@codesourcery.com>.
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify it under
  10 the terms of the GNU General Public License as published by the Free
  11 Software Foundation; either version 3, or (at your option) any later
  12 version.
  13
  14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17 for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING3.  If not see
  21 <http://www.gnu.org/licenses/>.  */
  22
  23 /* Routines declared in gcov-io.h.  This file should be #included by
  24    another source file, after having #included gcov-io.h.  */
  25
  26 #if !IN_GCOV
  27 static void gcov_write_block (unsigned);
  28 static gcov_unsigned_t *gcov_write_words (unsigned);
  29 #endif
  30 static const gcov_unsigned_t *gcov_read_words (unsigned);
  31 #if !IN_LIBGCOV
  32 static void gcov_allocate (unsigned);
  33 #endif
  34
  35 static inline gcov_unsigned_t from_file (gcov_unsigned_t value)
  36 {
  37 #if !IN_LIBGCOV
  38   if (gcov_var.endian)
  39     {
  40       value = (value >> 16) | (value << 16);
  41       value = ((value & 0xff00ff) << 8) | ((value >> 8) & 0xff00ff);
  42     }
  43 #endif
  44   return value;
  45 }
  46
  47 /* Open a gcov file. NAME is the name of the file to open and MODE
  48    indicates whether a new file should be created, or an existing file
  49    opened for modification. If MODE is >= 0 an existing file will be
  50    opened, if possible, and if MODE is <= 0, a new file will be
  51    created. Use MODE=0 to attempt to reopen an existing file and then
  52    fall back on creating a new one.  Return zero on failure, >0 on
  53    opening an existing file and <0 on creating a new one.  */
  54
  55 GCOV_LINKAGE int
  56 #if IN_LIBGCOV
  57 gcov_open (const char *name)
  58 #else
  59 gcov_open (const char *name, int mode)
  60 #endif
  61 {
  62 #if IN_LIBGCOV
  63   const int mode = 0;
  64 #endif
  65 #if GCOV_LOCKED
  66   struct flock s_flock;
  67   int fd;
  68
  69   s_flock.l_type = F_WRLCK;
  70   s_flock.l_whence = SEEK_SET;
  71   s_flock.l_start = 0;
  72   s_flock.l_len = 0; /* Until EOF.  */
  73   s_flock.l_pid = getpid ();
  74 #endif
  75
  76   gcc_assert (!gcov_var.file);
  77   gcov_var.start = 0;
  78   gcov_var.offset = gcov_var.length = 0;
  79   gcov_var.overread = -1u;
  80   gcov_var.error = 0;
  81 #if !IN_LIBGCOV
  82   gcov_var.endian = 0;
  83 #endif
  84 #if GCOV_LOCKED
  85   if (mode > 0)
  86     fd = open (name, O_RDWR);
  87   else
  88     fd = open (name, O_RDWR | O_CREAT, 0666);
  89   if (fd < 0)
  90     return 0;
  91
  92   while (fcntl (fd, F_SETLKW, &s_flock) && errno == EINTR)
  93     continue;
  94
  95   gcov_var.file = fdopen (fd, "r+b");
  96   if (!gcov_var.file)
  97     {
  98       close (fd);
  99       return 0;
 100     }
 101
 102   if (mode > 0)
 103     gcov_var.mode = 1;
 104   else if (mode == 0)
 105     {
 106       struct stat st;
 107
 108       if (fstat (fd, &st) < 0)
 109         {
 110           fclose (gcov_var.file);
 111           gcov_var.file = 0;
 112           return 0;
 113         }
 114       if (st.st_size != 0)
 115         gcov_var.mode = 1;
 116       else
 117         gcov_var.mode = mode * 2 + 1;
 118     }
 119   else
 120     gcov_var.mode = mode * 2 + 1;
 121 #else
 122   if (mode >= 0)
 123     gcov_var.file = fopen (name, "r+b");
 124   if (gcov_var.file)
 125     gcov_var.mode = 1;
 126   else if (mode <= 0)
 127     {
 128       gcov_var.file = fopen (name, "w+b");
 129       if (gcov_var.file)
 130         gcov_var.mode = mode * 2 + 1;
 131     }
 132   if (!gcov_var.file)
 133     return 0;
 134 #endif
 135
 136   setbuf (gcov_var.file, (char *)0);
 137
 138   return 1;
 139 }
 140
 141 /* Close the current gcov file. Flushes data to disk. Returns nonzero
 142    on failure or error flag set.  */
 143
 144 GCOV_LINKAGE int
 145 gcov_close (void)
 146 {
 147   if (gcov_var.file)
 148     {
 149 #if !IN_GCOV
 150       if (gcov_var.offset && gcov_var.mode < 0)
 151         gcov_write_block (gcov_var.offset);
 152 #endif
 153       fclose (gcov_var.file);
 154       gcov_var.file = 0;
 155       gcov_var.length = 0;
 156     }
 157 #if !IN_LIBGCOV
 158   free (gcov_var.buffer);
 159   gcov_var.alloc = 0;
 160   gcov_var.buffer = 0;
 161 #endif
 162   gcov_var.mode = 0;
 163   return gcov_var.error;
 164 }
 165
 166 #if !IN_LIBGCOV
 167 /* Check if MAGIC is EXPECTED. Use it to determine endianness of the
 168    file. Returns +1 for same endian, -1 for other endian and zero for
 169    not EXPECTED.  */
 170
 171 GCOV_LINKAGE int
 172 gcov_magic (gcov_unsigned_t magic, gcov_unsigned_t expected)
 173 {
 174   if (magic == expected)
 175     return 1;
 176   magic = (magic >> 16) | (magic << 16);
 177   magic = ((magic & 0xff00ff) << 8) | ((magic >> 8) & 0xff00ff);
 178   if (magic == expected)
 179     {
 180       gcov_var.endian = 1;
 181       return -1;
 182     }
 183   return 0;
 184 }
 185 #endif
 186
 187 #if !IN_LIBGCOV
 188 static void
 189 gcov_allocate (unsigned length)
 190 {
 191   size_t new_size = gcov_var.alloc;
 192
 193   if (!new_size)
 194     new_size = GCOV_BLOCK_SIZE;
 195   new_size += length;
 196   new_size *= 2;
 197
 198   gcov_var.alloc = new_size;
 199   gcov_var.buffer = xrealloc (gcov_var.buffer, new_size << 2);
 200 }
 201 #endif
 202
 203 #if !IN_GCOV
 204 /* Write out the current block, if needs be.  */
 205
 206 static void
 207 gcov_write_block (unsigned size)
 208 {
 209   if (fwrite (gcov_var.buffer, size << 2, 1, gcov_var.file) != 1)
 210     gcov_var.error = 1;
 211   gcov_var.start += size;
 212   gcov_var.offset -= size;
 213 }
 214
 215 /* Allocate space to write BYTES bytes to the gcov file. Return a
 216    pointer to those bytes, or NULL on failure.  */
 217
 218 static gcov_unsigned_t *
 219 gcov_write_words (unsigned words)
 220 {
 221   gcov_unsigned_t *result;
 222
 223   gcc_assert (gcov_var.mode < 0);
 224 #if IN_LIBGCOV
 225   if (gcov_var.offset >= GCOV_BLOCK_SIZE)
 226     {
 227       gcov_write_block (GCOV_BLOCK_SIZE);
 228       if (gcov_var.offset)
 229         {
 230           gcc_assert (gcov_var.offset == 1);
 231           memcpy (gcov_var.buffer, gcov_var.buffer + GCOV_BLOCK_SIZE, 4);
 232         }
 233     }
 234 #else
 235   if (gcov_var.offset + words > gcov_var.alloc)
 236     gcov_allocate (gcov_var.offset + words);
 237 #endif
 238   result = &gcov_var.buffer[gcov_var.offset];
 239   gcov_var.offset += words;
 240
 241   return result;
 242 }
 243
 244 /* Write unsigned VALUE to coverage file.  Sets error flag
 245    appropriately.  */
 246
 247 GCOV_LINKAGE void
 248 gcov_write_unsigned (gcov_unsigned_t value)
 249 {
 250   gcov_unsigned_t *buffer = gcov_write_words (1);
 251
 252   buffer[0] = value;
 253 }
 254
 255 /* Write counter VALUE to coverage file.  Sets error flag
 256    appropriately.  */
 257
 258 #if IN_LIBGCOV
 259 GCOV_LINKAGE void
 260 gcov_write_counter (gcov_type value)
 261 {
 262   gcov_unsigned_t *buffer = gcov_write_words (2);
 263
 264   buffer[0] = (gcov_unsigned_t) value;
 265   if (sizeof (value) > sizeof (gcov_unsigned_t))
 266     buffer[1] = (gcov_unsigned_t) (value >> 32);
 267   else
 268     buffer[1] = 0;
 269 }
 270 #endif /* IN_LIBGCOV */
 271
 272 #if !IN_LIBGCOV
 273 /* Write STRING to coverage file.  Sets error flag on file
 274    error, overflow flag on overflow */
 275
 276 GCOV_LINKAGE void
 277 gcov_write_string (const char *string)
 278 {
 279   unsigned length = 0;
 280   unsigned alloc = 0;
 281   gcov_unsigned_t *buffer;
 282
 283   if (string)
 284     {
 285       length = strlen (string);
 286       alloc = (length + 4) >> 2;
 287     }
 288
 289   buffer = gcov_write_words (1 + alloc);
 290
 291   buffer[0] = alloc;
 292   buffer[alloc] = 0;
 293   memcpy (&buffer[1], string, length);
 294 }
 295 #endif
 296
 297 #if !IN_LIBGCOV
 298 /* Write a tag TAG and reserve space for the record length. Return a
 299    value to be used for gcov_write_length.  */
 300
 301 GCOV_LINKAGE gcov_position_t
 302 gcov_write_tag (gcov_unsigned_t tag)
 303 {
 304   gcov_position_t result = gcov_var.start + gcov_var.offset;
 305   gcov_unsigned_t *buffer = gcov_write_words (2);
 306
 307   buffer[0] = tag;
 308   buffer[1] = 0;
 309
 310   return result;
 311 }
 312
 313 /* Write a record length using POSITION, which was returned by
 314    gcov_write_tag.  The current file position is the end of the
 315    record, and is restored before returning.  Returns nonzero on
 316    overflow.  */
 317
 318 GCOV_LINKAGE void
 319 gcov_write_length (gcov_position_t position)
 320 {
 321   unsigned offset;
 322   gcov_unsigned_t length;
 323   gcov_unsigned_t *buffer;
 324
 325   gcc_assert (gcov_var.mode < 0);
 326   gcc_assert (position + 2 <= gcov_var.start + gcov_var.offset);
 327   gcc_assert (position >= gcov_var.start);
 328   offset = position - gcov_var.start;
 329   length = gcov_var.offset - offset - 2;
 330   buffer = (gcov_unsigned_t *) &gcov_var.buffer[offset];
 331   buffer[1] = length;
 332   if (gcov_var.offset >= GCOV_BLOCK_SIZE)
 333     gcov_write_block (gcov_var.offset);
 334 }
 335
 336 #else /* IN_LIBGCOV */
 337
 338 /* Write a tag TAG and length LENGTH.  */
 339
 340 GCOV_LINKAGE void
 341 gcov_write_tag_length (gcov_unsigned_t tag, gcov_unsigned_t length)
 342 {
 343   gcov_unsigned_t *buffer = gcov_write_words (2);
 344
 345   buffer[0] = tag;
 346   buffer[1] = length;
 347 }
 348
 349 /* Write a summary structure to the gcov file.  Return nonzero on
 350    overflow.  */
 351
 352 GCOV_LINKAGE void
 353 gcov_write_summary (gcov_unsigned_t tag, const struct gcov_summary *summary)
 354 {
 355   unsigned ix;
 356   const struct gcov_ctr_summary *csum;
 357
 358   gcov_write_tag_length (tag, GCOV_TAG_SUMMARY_LENGTH);
 359   gcov_write_unsigned (summary->checksum);
 360   for (csum = summary->ctrs, ix = GCOV_COUNTERS_SUMMABLE; ix--; csum++)
 361     {
 362       gcov_write_unsigned (csum->num);
 363       gcov_write_unsigned (csum->runs);
 364       gcov_write_counter (csum->sum_all);
 365       gcov_write_counter (csum->run_max);
 366       gcov_write_counter (csum->sum_max);
 367     }
 368 }
 369 #endif /* IN_LIBGCOV */
 370
 371 #endif /*!IN_GCOV */
 372
 373 /* Return a pointer to read BYTES bytes from the gcov file. Returns
 374    NULL on failure (read past EOF).  */
 375
 376 static const gcov_unsigned_t *
 377 gcov_read_words (unsigned words)
 378 {
 379   const gcov_unsigned_t *result;
 380   unsigned excess = gcov_var.length - gcov_var.offset;
 381
 382   gcc_assert (gcov_var.mode > 0);
 383   if (excess < words)
 384     {
 385       gcov_var.start += gcov_var.offset;
 386 #if IN_LIBGCOV
 387       if (excess)
 388         {
 389           gcc_assert (excess == 1);
 390           memcpy (gcov_var.buffer, gcov_var.buffer + gcov_var.offset, 4);
 391         }
 392 #else
 393       memmove (gcov_var.buffer, gcov_var.buffer + gcov_var.offset, excess * 4);
 394 #endif
 395       gcov_var.offset = 0;
 396       gcov_var.length = excess;
 397 #if IN_LIBGCOV
 398       gcc_assert (!gcov_var.length || gcov_var.length == 1);
 399       excess = GCOV_BLOCK_SIZE;
 400 #else
 401       if (gcov_var.length + words > gcov_var.alloc)
 402         gcov_allocate (gcov_var.length + words);
 403       excess = gcov_var.alloc - gcov_var.length;
 404 #endif
 405       excess = fread (gcov_var.buffer + gcov_var.length,
 406                       1, excess << 2, gcov_var.file) >> 2;
 407       gcov_var.length += excess;
 408       if (gcov_var.length < words)
 409         {
 410           gcov_var.overread += words - gcov_var.length;
 411           gcov_var.length = 0;
 412           return 0;
 413         }
 414     }
 415   result = &gcov_var.buffer[gcov_var.offset];
 416   gcov_var.offset += words;
 417   return result;
 418 }
 419
 420 /* Read unsigned value from a coverage file. Sets error flag on file
 421    error, overflow flag on overflow */
 422
 423 GCOV_LINKAGE gcov_unsigned_t
 424 gcov_read_unsigned (void)
 425 {
 426   gcov_unsigned_t value;
 427   const gcov_unsigned_t *buffer = gcov_read_words (1);
 428
 429   if (!buffer)
 430     return 0;
 431   value = from_file (buffer[0]);
 432   return value;
 433 }
 434
 435 /* Read counter value from a coverage file. Sets error flag on file
 436    error, overflow flag on overflow */
 437
 438 GCOV_LINKAGE gcov_type
 439 gcov_read_counter (void)
 440 {
 441   gcov_type value;
 442   const gcov_unsigned_t *buffer = gcov_read_words (2);
 443
 444   if (!buffer)
 445     return 0;
 446   value = from_file (buffer[0]);
 447   if (sizeof (value) > sizeof (gcov_unsigned_t))
 448     value |= ((gcov_type) from_file (buffer[1])) << 32;
 449   else if (buffer[1])
 450     gcov_var.error = -1;
 451
 452   return value;
 453 }
 454
 455 /* Read string from coverage file. Returns a pointer to a static
 456    buffer, or NULL on empty string. You must copy the string before
 457    calling another gcov function.  */
 458
 459 #if !IN_LIBGCOV
 460 GCOV_LINKAGE const char *
 461 gcov_read_string (void)
 462 {
 463   unsigned length = gcov_read_unsigned ();
 464
 465   if (!length)
 466     return 0;
 467
 468   return (const char *) gcov_read_words (length);
 469 }
 470 #endif
 471
 472 GCOV_LINKAGE void
 473 gcov_read_summary (struct gcov_summary *summary)
 474 {
 475   unsigned ix;
 476   struct gcov_ctr_summary *csum;
 477
 478   summary->checksum = gcov_read_unsigned ();
 479   for (csum = summary->ctrs, ix = GCOV_COUNTERS_SUMMABLE; ix--; csum++)
 480     {
 481       csum->num = gcov_read_unsigned ();
 482       csum->runs = gcov_read_unsigned ();
 483       csum->sum_all = gcov_read_counter ();
 484       csum->run_max = gcov_read_counter ();
 485       csum->sum_max = gcov_read_counter ();
 486     }
 487 }
 488
 489 #if !IN_LIBGCOV
 490 /* Reset to a known position.  BASE should have been obtained from
 491    gcov_position, LENGTH should be a record length.  */
 492
 493 GCOV_LINKAGE void
 494 gcov_sync (gcov_position_t base, gcov_unsigned_t length)
 495 {
 496   gcc_assert (gcov_var.mode > 0);
 497   base += length;
 498   if (base - gcov_var.start <= gcov_var.length)
 499     gcov_var.offset = base - gcov_var.start;
 500   else
 501     {
 502       gcov_var.offset = gcov_var.length = 0;
 503       fseek (gcov_var.file, base << 2, SEEK_SET);
 504       gcov_var.start = ftell (gcov_var.file) >> 2;
 505     }
 506 }
 507 #endif
 508
 509 #if IN_LIBGCOV
 510 /* Move to the a set position in a gcov file.  */
 511
 512 GCOV_LINKAGE void
 513 gcov_seek (gcov_position_t base)
 514 {
 515   gcc_assert (gcov_var.mode < 0);
 516   if (gcov_var.offset)
 517     gcov_write_block (gcov_var.offset);
 518   fseek (gcov_var.file, base << 2, SEEK_SET);
 519   gcov_var.start = ftell (gcov_var.file) >> 2;
 520 }
 521 #endif
 522
 523 #if IN_GCOV > 0
 524 /* Return the modification time of the current gcov file.  */
 525
 526 GCOV_LINKAGE time_t
 527 gcov_time (void)
 528 {
 529   struct stat status;
 530
 531   if (fstat (fileno (gcov_var.file), &status))
 532     return 0;
 533   else
 534     return status.st_mtime;
 535 }
 536 #endif /* IN_GCOV */