gcc/gcov-io.c

   1 /* File format for coverage information
   2    Copyright (C) 1996, 1997, 1998, 2000, 2002, 2003, 2004
   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 2, 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 COPYING.  If not, write to the Free
  21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  22 02111-1307, USA.  */
  23
  24 /* Routines declared in gcov-io.h.  This file should be #included by
  25    another source file, after having #included gcov-io.h.  */
  26
  27 #if !IN_GCOV
  28 static void gcov_write_block (unsigned);
  29 static gcov_unsigned_t *gcov_write_words (unsigned);
  30 #endif
  31 static const gcov_unsigned_t *gcov_read_words (unsigned);
  32 #if !IN_LIBGCOV
  33 static void gcov_allocate (unsigned);
  34 #endif
  35
  36 static inline gcov_unsigned_t from_file (gcov_unsigned_t value)
  37 {
  38 #if !IN_LIBGCOV
  39   if (gcov_var.endian)
  40     {
  41       value = (value >> 16) | (value << 16);
  42       value = ((value & 0xff00ff) << 8) | ((value >> 8) & 0xff00ff);
  43     }
  44 #endif
  45   return value;
  46 }
  47
  48 /* Open a gcov file. NAME is the name of the file to open and MODE
  49    indicates whether a new file should be created, or an existing file
  50    opened for modification. If MODE is >= 0 an existing file will be
  51    opened, if possible, and if MODE is <= 0, a new file will be
  52    created. Use MODE=0 to attempt to reopen an existing file and then
  53    fall back on creating a new one.  Return zero on failure, >0 on
  54    opening an existing file and <0 on creating a new one.  */
  55
  56 GCOV_LINKAGE int
  57 #if IN_LIBGCOV
  58 gcov_open (const char *name)
  59 #else
  60 gcov_open (const char *name, int mode)
  61 #endif
  62 {
  63 #if IN_LIBGCOV
  64   const int mode = 0;
  65 #endif
  66 #if GCOV_LOCKED
  67   struct flock s_flock;
  68   int fd;
  69
  70   s_flock.l_type = F_WRLCK;
  71   s_flock.l_whence = SEEK_SET;
  72   s_flock.l_start = 0;
  73   s_flock.l_len = 0; /* Until EOF.  */
  74   s_flock.l_pid = getpid ();
  75 #endif
  76
  77   if (gcov_var.file)
  78     abort ();
  79   gcov_var.start = 0;
  80   gcov_var.offset = gcov_var.length = 0;
  81   gcov_var.overread = -1u;
  82   gcov_var.error = 0;
  83 #if !IN_LIBGCOV
  84   gcov_var.endian = 0;
  85 #endif
  86 #if GCOV_LOCKED
  87   if (mode > 0)
  88     fd = open (name, O_RDWR);
  89   else
  90     fd = open (name, O_RDWR | O_CREAT, 0666);
  91   if (fd < 0)
  92     return 0;
  93
  94   while (fcntl (fd, F_SETLKW, &s_flock) && errno == EINTR)
  95     continue;
  96
  97   gcov_var.file = fdopen (fd, "r+b");
  98   if (!gcov_var.file)
  99     {
 100       close (fd);
 101       return 0;
 102     }
 103
 104   if (mode > 0)
 105     gcov_var.mode = 1;
 106   else if (mode == 0)
 107     {
 108       struct stat st;
 109
 110       if (fstat (fd, &st) < 0)
 111         {
 112           fclose (gcov_var.file);
 113           gcov_var.file = 0;
 114           return 0;
 115         }
 116       if (st.st_size != 0)
 117         gcov_var.mode = 1;
 118       else
 119         gcov_var.mode = mode * 2 + 1;
 120     }
 121   else
 122     gcov_var.mode = mode * 2 + 1;
 123 #else
 124   if (mode >= 0)
 125     gcov_var.file = fopen (name, "r+b");
 126   if (gcov_var.file)
 127     gcov_var.mode = 1;
 128   else if (mode <= 0)
 129     {
 130       gcov_var.file = fopen (name, "w+b");
 131       if (gcov_var.file)
 132         gcov_var.mode = mode * 2 + 1;
 133     }
 134   if (!gcov_var.file)
 135     return 0;
 136 #endif
 137
 138   setbuf (gcov_var.file, (char *)0);
 139
 140   return 1;
 141 }
 142
 143 /* Close the current gcov file. Flushes data to disk. Returns nonzero
 144    on failure or error flag set.  */
 145
 146 GCOV_LINKAGE int
 147 gcov_close (void)
 148 {
 149   if (gcov_var.file)
 150     {
 151 #if !IN_GCOV
 152       if (gcov_var.offset && gcov_var.mode < 0)
 153         gcov_write_block (gcov_var.offset);
 154 #endif
 155       fclose (gcov_var.file);
 156       gcov_var.file = 0;
 157       gcov_var.length = 0;
 158     }
 159 #if !IN_LIBGCOV
 160   free (gcov_var.buffer);
 161   gcov_var.alloc = 0;
 162   gcov_var.buffer = 0;
 163 #endif
 164   gcov_var.mode = 0;
 165   return gcov_var.error;
 166 }
 167
 168 #if !IN_LIBGCOV
 169 /* Check if MAGIC is EXPECTED. Use it to determine endianness of the
 170    file. Returns +1 for same endian, -1 for other endian and zero for
 171    not EXPECTED.  */
 172
 173 GCOV_LINKAGE int
 174 gcov_magic (gcov_unsigned_t magic, gcov_unsigned_t expected)
 175 {
 176   if (magic == expected)
 177     return 1;
 178   magic = (magic >> 16) | (magic << 16);
 179   magic = ((magic & 0xff00ff) << 8) | ((magic >> 8) & 0xff00ff);
 180   if (magic == expected)
 181     {
 182       gcov_var.endian = 1;
 183       return -1;
 184     }
 185   return 0;
 186 }
 187 #endif
 188
 189 #if !IN_LIBGCOV
 190 static void
 191 gcov_allocate (unsigned length)
 192 {
 193   size_t new_size = gcov_var.alloc;
 194
 195   if (!new_size)
 196     new_size = GCOV_BLOCK_SIZE;
 197   new_size += length;
 198   new_size *= 2;
 199
 200   gcov_var.alloc = new_size;
 201   gcov_var.buffer = xrealloc (gcov_var.buffer, new_size << 2);
 202 }
 203 #endif
 204
 205 #if !IN_GCOV
 206 /* Write out the current block, if needs be.  */
 207
 208 static void
 209 gcov_write_block (unsigned size)
 210 {
 211   if (fwrite (gcov_var.buffer, size << 2, 1, gcov_var.file) != 1)
 212     gcov_var.error = 1;
 213   gcov_var.start += size;
 214   gcov_var.offset -= size;
 215 }
 216
 217 /* Allocate space to write BYTES bytes to the gcov file. Return a
 218    pointer to those bytes, or NULL on failure.  */
 219
 220 static gcov_unsigned_t *
 221 gcov_write_words (unsigned words)
 222 {
 223   gcov_unsigned_t *result;
 224
 225   GCOV_CHECK_WRITING ();
 226 #if IN_LIBGCOV
 227   if (gcov_var.offset >= GCOV_BLOCK_SIZE)
 228     {
 229       gcov_write_block (GCOV_BLOCK_SIZE);
 230       if (gcov_var.offset)
 231         {
 232           GCOV_CHECK (gcov_var.offset == 1);
 233           memcpy (gcov_var.buffer, gcov_var.buffer + GCOV_BLOCK_SIZE, 4);
 234         }
 235     }
 236 #else
 237   if (gcov_var.offset + words > gcov_var.alloc)
 238     gcov_allocate (gcov_var.offset + words);
 239 #endif
 240   result = &gcov_var.buffer[gcov_var.offset];
 241   gcov_var.offset += words;
 242
 243   return result;
 244 }
 245
 246 /* Write unsigned VALUE to coverage file.  Sets error flag
 247    appropriately.  */
 248
 249 GCOV_LINKAGE void
 250 gcov_write_unsigned (gcov_unsigned_t value)
 251 {
 252   gcov_unsigned_t *buffer = gcov_write_words (1);
 253
 254   buffer[0] = value;
 255 }
 256
 257 /* Write counter VALUE to coverage file.  Sets error flag
 258    appropriately.  */
 259
 260 #if IN_LIBGCOV
 261 GCOV_LINKAGE void
 262 gcov_write_counter (gcov_type value)
 263 {
 264   gcov_unsigned_t *buffer = gcov_write_words (2);
 265
 266   buffer[0] = (gcov_unsigned_t) value;
 267   if (sizeof (value) > sizeof (gcov_unsigned_t))
 268     buffer[1] = (gcov_unsigned_t) (value >> 32);
 269   else
 270     buffer[1] = 0;
 271
 272   if (value < 0)
 273     gcov_var.error = -1;
 274 }
 275 #endif /* IN_LIBGCOV */
 276
 277 #if !IN_LIBGCOV
 278 /* Write STRING to coverage file.  Sets error flag on file
 279    error, overflow flag on overflow */
 280
 281 GCOV_LINKAGE void
 282 gcov_write_string (const char *string)
 283 {
 284   unsigned length = 0;
 285   unsigned alloc = 0;
 286   gcov_unsigned_t *buffer;
 287
 288   if (string)
 289     {
 290       length = strlen (string);
 291       alloc = (length + 4) >> 2;
 292     }
 293
 294   buffer = gcov_write_words (1 + alloc);
 295
 296   buffer[0] = alloc;
 297   buffer[alloc] = 0;
 298   memcpy (&buffer[1], string, length);
 299 }
 300 #endif
 301
 302 #if !IN_LIBGCOV
 303 /* Write a tag TAG and reserve space for the record length. Return a
 304    value to be used for gcov_write_length.  */
 305
 306 GCOV_LINKAGE gcov_position_t
 307 gcov_write_tag (gcov_unsigned_t tag)
 308 {
 309   gcov_position_t result = gcov_var.start + gcov_var.offset;
 310   gcov_unsigned_t *buffer = gcov_write_words (2);
 311
 312   buffer[0] = tag;
 313   buffer[1] = 0;
 314
 315   return result;
 316 }
 317
 318 /* Write a record length using POSITION, which was returned by
 319    gcov_write_tag.  The current file position is the end of the
 320    record, and is restored before returning.  Returns nonzero on
 321    overflow.  */
 322
 323 GCOV_LINKAGE void
 324 gcov_write_length (gcov_position_t position)
 325 {
 326   unsigned offset;
 327   gcov_unsigned_t length;
 328   gcov_unsigned_t *buffer;
 329
 330   GCOV_CHECK_WRITING ();
 331   GCOV_CHECK (position + 2 <= gcov_var.start + gcov_var.offset);
 332   GCOV_CHECK (position >= gcov_var.start);
 333   offset = position - gcov_var.start;
 334   length = gcov_var.offset - offset - 2;
 335   buffer = (gcov_unsigned_t *) &gcov_var.buffer[offset];
 336   buffer[1] = length;
 337   if (gcov_var.offset >= GCOV_BLOCK_SIZE)
 338     gcov_write_block (gcov_var.offset);
 339 }
 340
 341 #else /* IN_LIBGCOV */
 342
 343 /* Write a tag TAG and length LENGTH.  */
 344
 345 GCOV_LINKAGE void
 346 gcov_write_tag_length (gcov_unsigned_t tag, gcov_unsigned_t length)
 347 {
 348   gcov_unsigned_t *buffer = gcov_write_words (2);
 349
 350   buffer[0] = tag;
 351   buffer[1] = length;
 352 }
 353
 354 /* Write a summary structure to the gcov file.  Return nonzero on
 355    overflow.  */
 356
 357 GCOV_LINKAGE void
 358 gcov_write_summary (gcov_unsigned_t tag, const struct gcov_summary *summary)
 359 {
 360   unsigned ix;
 361   const struct gcov_ctr_summary *csum;
 362
 363   gcov_write_tag_length (tag, GCOV_TAG_SUMMARY_LENGTH);
 364   gcov_write_unsigned (summary->checksum);
 365   for (csum = summary->ctrs, ix = GCOV_COUNTERS_SUMMABLE; ix--; csum++)
 366     {
 367       gcov_write_unsigned (csum->num);
 368       gcov_write_unsigned (csum->runs);
 369       gcov_write_counter (csum->sum_all);
 370       gcov_write_counter (csum->run_max);
 371       gcov_write_counter (csum->sum_max);
 372     }
 373 }
 374 #endif /* IN_LIBGCOV */
 375
 376 #endif /*!IN_GCOV */
 377
 378 /* Return a pointer to read BYTES bytes from the gcov file. Returns
 379    NULL on failure (read past EOF).  */
 380
 381 static const gcov_unsigned_t *
 382 gcov_read_words (unsigned words)
 383 {
 384   const gcov_unsigned_t *result;
 385   unsigned excess = gcov_var.length - gcov_var.offset;
 386
 387   GCOV_CHECK_READING ();
 388   if (excess < words)
 389     {
 390       gcov_var.start += gcov_var.offset;
 391 #if IN_LIBGCOV
 392       if (excess)
 393         {
 394           GCOV_CHECK (excess == 1);
 395           memcpy (gcov_var.buffer, gcov_var.buffer + gcov_var.offset, 4);
 396         }
 397 #else
 398       memmove (gcov_var.buffer, gcov_var.buffer + gcov_var.offset, excess * 4);
 399 #endif
 400       gcov_var.offset = 0;
 401       gcov_var.length = excess;
 402 #if IN_LIBGCOV
 403       GCOV_CHECK (!gcov_var.length || gcov_var.length == 1);
 404       excess = GCOV_BLOCK_SIZE;
 405 #else
 406       if (gcov_var.length + words > gcov_var.alloc)
 407         gcov_allocate (gcov_var.length + words);
 408       excess = gcov_var.alloc - gcov_var.length;
 409 #endif
 410       excess = fread (gcov_var.buffer + gcov_var.length,
 411                       1, excess << 2, gcov_var.file) >> 2;
 412       gcov_var.length += excess;
 413       if (gcov_var.length < words)
 414         {
 415           gcov_var.overread += words - gcov_var.length;
 416           gcov_var.length = 0;
 417           return 0;
 418         }
 419     }
 420   result = &gcov_var.buffer[gcov_var.offset];
 421   gcov_var.offset += words;
 422   return result;
 423 }
 424
 425 /* Read unsigned value from a coverage file. Sets error flag on file
 426    error, overflow flag on overflow */
 427
 428 GCOV_LINKAGE gcov_unsigned_t
 429 gcov_read_unsigned (void)
 430 {
 431   gcov_unsigned_t value;
 432   const gcov_unsigned_t *buffer = gcov_read_words (1);
 433
 434   if (!buffer)
 435     return 0;
 436   value = from_file (buffer[0]);
 437   return value;
 438 }
 439
 440 /* Read counter value from a coverage file. Sets error flag on file
 441    error, overflow flag on overflow */
 442
 443 GCOV_LINKAGE gcov_type
 444 gcov_read_counter (void)
 445 {
 446   gcov_type value;
 447   const gcov_unsigned_t *buffer = gcov_read_words (2);
 448
 449   if (!buffer)
 450     return 0;
 451   value = from_file (buffer[0]);
 452   if (sizeof (value) > sizeof (gcov_unsigned_t))
 453     value |= ((gcov_type) from_file (buffer[1])) << 32;
 454   else if (buffer[1])
 455     gcov_var.error = -1;
 456
 457   if (value < 0)
 458     gcov_var.error = -1;
 459   return value;
 460 }
 461
 462 /* Read string from coverage file. Returns a pointer to a static
 463    buffer, or NULL on empty string. You must copy the string before
 464    calling another gcov function.  */
 465
 466 #if !IN_LIBGCOV
 467 GCOV_LINKAGE const char *
 468 gcov_read_string (void)
 469 {
 470   unsigned length = gcov_read_unsigned ();
 471
 472   if (!length)
 473     return 0;
 474
 475   return (const char *) gcov_read_words (length);
 476 }
 477 #endif
 478
 479 GCOV_LINKAGE void
 480 gcov_read_summary (struct gcov_summary *summary)
 481 {
 482   unsigned ix;
 483   struct gcov_ctr_summary *csum;
 484
 485   summary->checksum = gcov_read_unsigned ();
 486   for (csum = summary->ctrs, ix = GCOV_COUNTERS_SUMMABLE; ix--; csum++)
 487     {
 488       csum->num = gcov_read_unsigned ();
 489       csum->runs = gcov_read_unsigned ();
 490       csum->sum_all = gcov_read_counter ();
 491       csum->run_max = gcov_read_counter ();
 492       csum->sum_max = gcov_read_counter ();
 493     }
 494 }
 495
 496 #if !IN_LIBGCOV
 497 /* Reset to a known position.  BASE should have been obtained from
 498    gcov_position, LENGTH should be a record length.  */
 499
 500 GCOV_LINKAGE void
 501 gcov_sync (gcov_position_t base, gcov_unsigned_t length)
 502 {
 503   GCOV_CHECK_READING ();
 504   base += length;
 505   if (base - gcov_var.start <= gcov_var.length)
 506     gcov_var.offset = base - gcov_var.start;
 507   else
 508     {
 509       gcov_var.offset = gcov_var.length = 0;
 510       fseek (gcov_var.file, base << 2, SEEK_SET);
 511       gcov_var.start = ftell (gcov_var.file) >> 2;
 512     }
 513 }
 514 #endif
 515
 516 #if IN_LIBGCOV
 517 /* Move to the a set position in a gcov file.  BASE is zero to move to
 518    the end, and nonzero to move to that position.  */
 519
 520 GCOV_LINKAGE void
 521 gcov_seek (gcov_position_t base)
 522 {
 523   GCOV_CHECK_WRITING ();
 524   if (gcov_var.offset)
 525     gcov_write_block (gcov_var.offset);
 526   fseek (gcov_var.file, base << 2, base ? SEEK_SET : SEEK_END);
 527   gcov_var.start = ftell (gcov_var.file) >> 2;
 528 }
 529 #endif
 530
 531 #if IN_GCOV > 0
 532 /* Return the modification time of the current gcov file.  */
 533
 534 GCOV_LINKAGE time_t
 535 gcov_time (void)
 536 {
 537   struct stat status;
 538
 539   if (fstat (fileno (gcov_var.file), &status))
 540     return 0;
 541   else
 542     return status.st_mtime;
 543 }
 544 #endif /* IN_GCOV */