gcc/gcov-io.c

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