gcc/gcov-io.h

   1 /* File format for coverage information
   2    Copyright (C) 1996, 1997, 1998, 2000, 2002,
   3    2003, 2004 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 /* As a special exception, if you link this library with other files,
  25    some of which are compiled with GCC, to produce an executable,
  26    this library does not by itself cause the resulting executable
  27    to be covered by the GNU General Public License.
  28    This exception does not however invalidate any other reasons why
  29    the executable file might be covered by the GNU General Public License.  */
  30
  31 /* Coverage information is held in two files.  A notes file, which is
  32    generated by the compiler, and a data file, which is generated by
  33    the program under test.  Both files use a similar structure.  We do
  34    not attempt to make these files backwards compatible with previous
  35    versions, as you only need coverage information when developing a
  36    program.  We do hold version information, so that mismatches can be
  37    detected, and we use a format that allows tools to skip information
  38    they do not understand or are not interested in.
  39
  40    Numbers are recorded in the 32 bit unsigned binary form of the
  41    endianness of the machine generating the file. 64 bit numbers are
  42    stored as two 32 bit numbers, the low part first.  Strings are
  43    padded with 1 to 4 NUL bytes, to bring the length up to a multiple
  44    of 4. The number of 4 bytes is stored, followed by the padded
  45    string. Zero length and NULL strings are simply stored as a length
  46    of zero (they have no trailing NUL or padding).
  47
  48         int32:  byte3 byte2 byte1 byte0 | byte0 byte1 byte2 byte3
  49         int64:  int32:low int32:high
  50         string: int32:0 | int32:length char* char:0 padding
  51         padding: | char:0 | char:0 char:0 | char:0 char:0 char:0
  52         item: int32 | int64 | string
  53
  54    The basic format of the files is
  55
  56         file : int32:magic int32:version int32:stamp record*
  57
  58    The magic ident is different for the notes and the data files.  The
  59    magic ident is used to determine the endianness of the file, when
  60    reading.  The version is the same for both files and is derived
  61    from gcc's version number. The stamp value is used to synchronize
  62    note and data files and to synchronize merging within a data
  63    file. It need not be an absolute time stamp, merely a ticker that
  64    increments fast enough and cycles slow enough to distinguish
  65    different compile/run/compile cycles.
  66
  67    Although the ident and version are formally 32 bit numbers, they
  68    are derived from 4 character ASCII strings.  The version number
  69    consists of the single character major version number, a two
  70    character minor version number (leading zero for versions less than
  71    10), and a single character indicating the status of the release.
  72    That will be 'e' experimental, 'p' prerelease and 'r' for release.
  73    Because, by good fortune, these are in alphabetical order, string
  74    collating can be used to compare version strings.  Be aware that
  75    the 'e' designation will (naturally) be unstable and might be
  76    incompatible with itself.  For gcc 3.4 experimental, it would be
  77    '304e' (0x33303465).  When the major version reaches 10, the
  78    letters A-Z will be used.  Assuming minor increments releases every
  79    6 months, we have to make a major increment every 50 years.
  80    Assuming major increments releases every 5 years, we're ok for the
  81    next 155 years -- good enough for me.
  82
  83    A record has a tag, length and variable amount of data.
  84
  85         record: header data
  86         header: int32:tag int32:length
  87         data: item*
  88
  89    Records are not nested, but there is a record hierarchy.  Tag
  90    numbers reflect this hierarchy.  Tags are unique across note and
  91    data files.  Some record types have a varying amount of data.  The
  92    LENGTH is the number of 4bytes that follow and is usually used to
  93    determine how much data.  The tag value is split into 4 8-bit
  94    fields, one for each of four possible levels.  The most significant
  95    is allocated first.  Unused levels are zero.  Active levels are
  96    odd-valued, so that the LSB of the level is one.  A sub-level
  97    incorporates the values of its superlevels.  This formatting allows
  98    you to determine the tag hierarchy, without understanding the tags
  99    themselves, and is similar to the standard section numbering used
 100    in technical documents.  Level values [1..3f] are used for common
 101    tags, values [41..9f] for the notes file and [a1..ff] for the data
 102    file.
 103
 104    The basic block graph file contains the following records
 105         note: unit function-graph*
 106         unit: header int32:checksum string:source
 107         function-graph: announce_function basic_blocks {arcs | lines}*
 108         announce_function: header int32:ident int32:checksum
 109                 string:name string:source int32:lineno
 110         basic_block: header int32:flags*
 111         arcs: header int32:block_no arc*
 112         arc:  int32:dest_block int32:flags
 113         lines: header int32:block_no line*
 114                int32:0 string:NULL
 115         line:  int32:line_no | int32:0 string:filename
 116
 117    The BASIC_BLOCK record holds per-bb flags.  The number of blocks
 118    can be inferred from its data length.  There is one ARCS record per
 119    basic block.  The number of arcs from a bb is implicit from the
 120    data length.  It enumerates the destination bb and per-arc flags.
 121    There is one LINES record per basic block, it enumerates the source
 122    lines which belong to that basic block.  Source file names are
 123    introduced by a line number of 0, following lines are from the new
 124    source file.  The initial source file for the function is NULL, but
 125    the current source file should be remembered from one LINES record
 126    to the next.  The end of a block is indicated by an empty filename
 127    - this does not reset the current source file.  Note there is no
 128    ordering of the ARCS and LINES records: they may be in any order,
 129    interleaved in any manner.  The current filename follows the order
 130    the LINES records are stored in the file, *not* the ordering of the
 131    blocks they are for.
 132
 133    The data file contains the following records.
 134         data: {unit function-data* summary:object summary:program*}*
 135         unit: header int32:checksum
 136         function-data:  announce_function arc_counts
 137         announce_function: header int32:ident int32:checksum
 138         arc_counts: header int64:count*
 139         summary: int32:checksum {count-summary}GCOV_COUNTERS
 140         count-summary:  int32:num int32:runs int64:sum
 141                         int64:max int64:sum_max
 142
 143    The ANNOUNCE_FUNCTION record is the same as that in the note file,
 144    but without the source location.  The ARC_COUNTS gives the counter
 145    values for those arcs that are instrumented.  The SUMMARY records
 146    give information about the whole object file and about the whole
 147    program.  The checksum is used for whole program summaries, and
 148    disambiguates different programs which include the same
 149    instrumented object file.  There may be several program summaries,
 150    each with a unique checksum.  The object summary's checksum is zero.
 151    Note that the data file might contain information from several runs
 152    concatenated, or the data might be merged.
 153
 154    This file is included by both the compiler, gcov tools and the
 155    runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to
 156    distinguish which case is which.  If IN_LIBGCOV is nonzero,
 157    libgcov is being built. If IN_GCOV is nonzero, the gcov tools are
 158    being built. Otherwise the compiler is being built. IN_GCOV may be
 159    positive or negative. If positive, we are compiling a tool that
 160    requires additional functions (see the code for knowledge of what
 161    those functions are).  */
 162
 163 #ifndef GCC_GCOV_IO_H
 164 #define GCC_GCOV_IO_H
 165
 166 #if IN_LIBGCOV
 167 /* About the target */
 168
 169 #if BITS_PER_UNIT == 8
 170 typedef unsigned gcov_unsigned_t __attribute__ ((mode (SI)));
 171 typedef unsigned gcov_position_t __attribute__ ((mode (SI)));
 172 #if LONG_LONG_TYPE_SIZE > 32
 173 typedef signed gcov_type __attribute__ ((mode (DI)));
 174 #else
 175 typedef signed gcov_type __attribute__ ((mode (SI)));
 176 #endif
 177 #else
 178 #if BITS_PER_UNIT == 16
 179 typedef unsigned gcov_unsigned_t __attribute__ ((mode (HI)));
 180 typedef unsigned gcov_position_t __attribute__ ((mode (HI)));
 181 #if LONG_LONG_TYPE_SIZE > 32
 182 typedef signed gcov_type __attribute__ ((mode (SI)));
 183 #else
 184 typedef signed gcov_type __attribute__ ((mode (HI)));
 185 #endif
 186 #else
 187 typedef unsigned gcov_unsigned_t __attribute__ ((mode (QI)));
 188 typedef unsigned gcov_position_t __attribute__ ((mode (QI)));
 189 #if LONG_LONG_TYPE_SIZE > 32
 190 typedef signed gcov_type __attribute__ ((mode (HI)));
 191 #else
 192 typedef signed gcov_type __attribute__ ((mode (QI)));
 193 #endif
 194 #endif
 195 #endif
 196
 197
 198 #if defined (TARGET_HAS_F_SETLKW)
 199 #define GCOV_LOCKED 1
 200 #else
 201 #define GCOV_LOCKED 0
 202 #endif
 203
 204 #else /* !IN_LIBGCOV */
 205 /* About the host */
 206
 207 typedef unsigned gcov_unsigned_t;
 208 typedef unsigned gcov_position_t;
 209 /* gcov_type is typedef'd elsewhere for the compiler */
 210 #if IN_GCOV
 211 #define GCOV_LINKAGE static
 212 typedef HOST_WIDEST_INT gcov_type;
 213 #if IN_GCOV > 0
 214 #include <sys/types.h>
 215 #endif
 216 #else /*!IN_GCOV */
 217 #if LONG_LONG_TYPE_SIZE > 32
 218 #define GCOV_TYPE_NODE intDI_type_node
 219 #else
 220 #define GCOV_TYPE_NODE intSI_type_node
 221 #endif
 222 #endif
 223
 224 #if defined (HOST_HAS_F_SETLKW)
 225 #define GCOV_LOCKED 1
 226 #else
 227 #define GCOV_LOCKED 0
 228 #endif
 229
 230 #endif /* !IN_LIBGCOV */
 231
 232 /* In gcov we want function linkage to be static. In libgcov we need
 233    these functions to be extern, so prefix them with __gcov.  In the
 234    compiler we want it extern, so that they can be accessed from
 235    elsewhere.  */
 236 #if IN_LIBGCOV
 237 #define gcov_var __gcov_var
 238 #define gcov_open __gcov_open
 239 #define gcov_close __gcov_close
 240 #define gcov_write_tag_length __gcov_write_tag_length
 241 #define gcov_position __gcov_position
 242 #define gcov_seek __gcov_seek
 243 #define gcov_rewrite __gcov_rewrite
 244 #define gcov_is_error __gcov_is_error
 245 #define gcov_write_unsigned __gcov_write_unsigned
 246 #define gcov_write_counter __gcov_write_counter
 247 #define gcov_write_summary __gcov_write_summary
 248 #define gcov_read_unsigned __gcov_read_unsigned
 249 #define gcov_read_counter __gcov_read_counter
 250 #define gcov_read_summary __gcov_read_summary
 251
 252 /* Poison these, so they don't accidentally slip in.  */
 253 #pragma GCC poison gcov_write_string gcov_write_tag gcov_write_length
 254 #pragma GCC poison gcov_read_string gcov_sync gcov_time gcov_magic
 255
 256 #endif
 257
 258 #ifndef GCOV_LINKAGE
 259 #define GCOV_LINKAGE extern
 260 #endif
 261
 262 /* File suffixes.  */
 263 #define GCOV_DATA_SUFFIX ".gcda"
 264 #define GCOV_NOTE_SUFFIX ".gcno"
 265
 266 /* File magic. Must not be palindromes.  */
 267 #define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */
 268 #define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */
 269
 270 /* gcov-iov.h is automatically generated by the makefile from
 271    version.c, it looks like
 272         #define GCOV_VERSION ((gcov_unsigned_t)0x89abcdef)
 273 */
 274 #include "gcov-iov.h"
 275
 276 /* Convert a magic or version number to a 4 character string.  */
 277 #define GCOV_UNSIGNED2STRING(ARRAY,VALUE)       \
 278   ((ARRAY)[0] = (char)((VALUE) >> 24),          \
 279    (ARRAY)[1] = (char)((VALUE) >> 16),          \
 280    (ARRAY)[2] = (char)((VALUE) >> 8),           \
 281    (ARRAY)[3] = (char)((VALUE) >> 0))
 282
 283 /* The record tags.  Values [1..3f] are for tags which may be in either
 284    file.  Values [41..9f] for those in the note file and [a1..ff] for
 285    the data file.  The tag value zero is used as an explicit end of
 286    file marker -- it is not required to be present.  */
 287
 288 #define GCOV_TAG_FUNCTION        ((gcov_unsigned_t)0x01000000)
 289 #define GCOV_TAG_FUNCTION_LENGTH (2)
 290 #define GCOV_TAG_BLOCKS          ((gcov_unsigned_t)0x01410000)
 291 #define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM)
 292 #define GCOV_TAG_BLOCKS_NUM(LENGTH) (LENGTH)
 293 #define GCOV_TAG_ARCS            ((gcov_unsigned_t)0x01430000)
 294 #define GCOV_TAG_ARCS_LENGTH(NUM)  (1 + (NUM) * 2)
 295 #define GCOV_TAG_ARCS_NUM(LENGTH)  (((LENGTH) - 1) / 2)
 296 #define GCOV_TAG_LINES           ((gcov_unsigned_t)0x01450000)
 297 #define GCOV_TAG_COUNTER_BASE    ((gcov_unsigned_t)0x01a10000)
 298 #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2)
 299 #define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2)
 300 #define GCOV_TAG_OBJECT_SUMMARY  ((gcov_unsigned_t)0xa1000000)
 301 #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000)
 302 #define GCOV_TAG_SUMMARY_LENGTH  \
 303         (1 + GCOV_COUNTERS_SUMMABLE * (2 + 3 * 2))
 304
 305 /* Counters that are collected.  */
 306 #define GCOV_COUNTER_ARCS       0  /* Arc transitions.  */
 307 #define GCOV_COUNTERS_SUMMABLE  1  /* Counters which can be
 308                                       summaried.  */
 309 #define GCOV_FIRST_VALUE_COUNTER 1 /* The first of counters used for value
 310                                       profiling.  They must form a consecutive
 311                                       interval and their order must match
 312                                       the order of HIST_TYPEs in
 313                                       value-prof.h.  */
 314 #define GCOV_COUNTER_V_INTERVAL 1  /* Histogram of value inside an interval.  */
 315 #define GCOV_COUNTER_V_POW2     2  /* Histogram of exact power2 logarithm
 316                                       of a value.  */
 317 #define GCOV_COUNTER_V_SINGLE   3  /* The most common value of expression.  */
 318 #define GCOV_COUNTER_V_DELTA    4  /* The most common difference between
 319                                       consecutive values of expression.  */
 320 #define GCOV_LAST_VALUE_COUNTER 4  /* The last of counters used for value
 321                                       profiling.  */
 322 #define GCOV_COUNTERS           5
 323
 324 /* Number of counters used for value profiling.  */
 325 #define GCOV_N_VALUE_COUNTERS \
 326   (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1)
 327
 328   /* A list of human readable names of the counters */
 329 #define GCOV_COUNTER_NAMES      {"arcs", "interval", "pow2", "single", "delta"}
 330
 331   /* Names of merge functions for counters.  */
 332 #define GCOV_MERGE_FUNCTIONS    {"__gcov_merge_add",    \
 333                                  "__gcov_merge_add",    \
 334                                  "__gcov_merge_add",    \
 335                                  "__gcov_merge_single", \
 336                                  "__gcov_merge_delta"}
 337
 338 /* Convert a counter index to a tag.  */
 339 #define GCOV_TAG_FOR_COUNTER(COUNT)                             \
 340         (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17))
 341 /* Convert a tag to a counter.  */
 342 #define GCOV_COUNTER_FOR_TAG(TAG)                                       \
 343         ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17))
 344 /* Check whether a tag is a counter tag.  */
 345 #define GCOV_TAG_IS_COUNTER(TAG)                                \
 346         (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS)
 347
 348 /* The tag level mask has 1's in the position of the inner levels, &
 349    the lsb of the current level, and zero on the current and outer
 350    levels.  */
 351 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
 352
 353 /* Return nonzero if SUB is an immediate subtag of TAG.  */
 354 #define GCOV_TAG_IS_SUBTAG(TAG,SUB)                             \
 355         (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB)        \
 356          && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK(TAG)))
 357
 358 /* Return nonzero if SUB is at a sublevel to TAG.  */
 359 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB)                           \
 360         (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
 361
 362 /* Basic block flags.  */
 363 #define GCOV_BLOCK_UNEXPECTED   (1 << 1)
 364
 365 /* Arc flags.  */
 366 #define GCOV_ARC_ON_TREE        (1 << 0)
 367 #define GCOV_ARC_FAKE           (1 << 1)
 368 #define GCOV_ARC_FALLTHROUGH    (1 << 2)
 369
 370 /* Structured records.  */
 371
 372 /* Cumulative counter data.  */
 373 struct gcov_ctr_summary
 374 {
 375   gcov_unsigned_t num;          /* number of counters.  */
 376   gcov_unsigned_t runs;         /* number of program runs */
 377   gcov_type sum_all;            /* sum of all counters accumulated.  */
 378   gcov_type run_max;            /* maximum value on a single run.  */
 379   gcov_type sum_max;            /* sum of individual run max values.  */
 380 };
 381
 382 /* Object & program summary record.  */
 383 struct gcov_summary
 384 {
 385   gcov_unsigned_t checksum;     /* checksum of program */
 386   struct gcov_ctr_summary ctrs[GCOV_COUNTERS_SUMMABLE];
 387 };
 388
 389 /* Structures embedded in coveraged program.  The structures generated
 390    by write_profile must match these.  */
 391
 392 #if IN_LIBGCOV
 393 /* Information about a single function.  This uses the trailing array
 394    idiom. The number of counters is determined from the counter_mask
 395    in gcov_info.  We hold an array of function info, so have to
 396    explicitly calculate the correct array stride.  */
 397 struct gcov_fn_info
 398 {
 399   gcov_unsigned_t ident;        /* unique ident of function */
 400   gcov_unsigned_t checksum;     /* function checksum */
 401   unsigned n_ctrs[0];           /* instrumented counters */
 402 };
 403
 404 /* Type of function used to merge counters.  */
 405 typedef void (*gcov_merge_fn) (gcov_type *, gcov_unsigned_t);
 406
 407 /* Information about counters.  */
 408 struct gcov_ctr_info
 409 {
 410   gcov_unsigned_t num;          /* number of counters.  */
 411   gcov_type *values;            /* their values.  */
 412   gcov_merge_fn merge;          /* The function used to merge them.  */
 413 };
 414
 415 /* Information about a single object file.  */
 416 struct gcov_info
 417 {
 418   gcov_unsigned_t version;      /* expected version number */
 419   struct gcov_info *next;       /* link to next, used by libgcov */
 420
 421   gcov_unsigned_t stamp;        /* uniquifying time stamp */
 422   const char *filename;         /* output file name */
 423
 424   unsigned n_functions;         /* number of functions */
 425   const struct gcov_fn_info *functions; /* table of functions */
 426
 427   unsigned ctr_mask;            /* mask of counters instrumented.  */
 428   struct gcov_ctr_info counts[0]; /* count data. The number of bits
 429                                      set in the ctr_mask field
 430                                      determines how big this array
 431                                      is.  */
 432 };
 433
 434 /* Register a new object file module.  */
 435 extern void __gcov_init (struct gcov_info *);
 436
 437 /* Called before fork, to avoid double counting.  */
 438 extern void __gcov_flush (void);
 439
 440 /* The merge function that just sums the counters.  */
 441 extern void __gcov_merge_add (gcov_type *, unsigned);
 442
 443 /* The merge function to choose the most common value.  */
 444 extern void __gcov_merge_single (gcov_type *, unsigned);
 445
 446 /* The merge function to choose the most common difference between
 447    consecutive values.  */
 448 extern void __gcov_merge_delta (gcov_type *, unsigned);
 449
 450 #ifndef inhibit_libc
 451 /* The wrappers around some library functions..  */
 452 extern pid_t __gcov_fork (void);
 453 extern int __gcov_execl (const char *, const char *, ...);
 454 extern int __gcov_execlp (const char *, const char *, ...);
 455 extern int __gcov_execle (const char *,  const char *, ...);
 456 extern int __gcov_execv (const char *, char *const []);
 457 extern int __gcov_execvp (const char *, char *const []);
 458 extern int __gcov_execve (const char *, char  *const [], char *const []);
 459 #endif
 460
 461 #endif /* IN_LIBGCOV */
 462
 463 #if IN_LIBGCOV >= 0
 464
 465 /* Optimum number of gcov_unsigned_t's read from or written to disk.  */
 466 #define GCOV_BLOCK_SIZE (1 << 10)
 467
 468 GCOV_LINKAGE struct gcov_var
 469 {
 470   FILE *file;
 471   gcov_position_t start;        /* Position of first byte of block */
 472   unsigned offset;              /* Read/write position within the block.  */
 473   unsigned length;              /* Read limit in the block.  */
 474   unsigned overread;            /* Number of words overread.  */
 475   int error;                    /* < 0 overflow, > 0 disk error.  */
 476   int mode;                     /* < 0 writing, > 0 reading */
 477 #if IN_LIBGCOV
 478   /* Holds one block plus 4 bytes, thus all coverage reads & writes
 479      fit within this buffer and we always can transfer GCOV_BLOCK_SIZE
 480      to and from the disk. libgcov never backtracks and only writes 4
 481      or 8 byte objects.  */
 482   gcov_unsigned_t buffer[GCOV_BLOCK_SIZE + 1];
 483 #else
 484   int endian;                   /* Swap endianness.  */
 485   /* Holds a variable length block, as the compiler can write
 486      strings and needs to backtrack.  */
 487   size_t alloc;
 488   gcov_unsigned_t *buffer;
 489 #endif
 490 } gcov_var;
 491
 492 /* Functions for reading and writing gcov files. In libgcov you can
 493    open the file for reading then writing. Elsewhere you can open the
 494    file either for reading or for writing. When reading a file you may
 495    use the gcov_read_* functions, gcov_sync, gcov_position, &
 496    gcov_error. When writing a file you may use the gcov_write
 497    functions, gcov_seek & gcov_error. When a file is to be rewritten
 498    you use the functions for reading, then gcov_rewrite then the
 499    functions for writing.  Your file may become corrupted if you break
 500    these invariants.  */
 501 #if IN_LIBGCOV
 502 GCOV_LINKAGE int gcov_open (const char */*name*/);
 503 #else
 504 GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/);
 505 GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t);
 506 #endif
 507 GCOV_LINKAGE int gcov_close (void);
 508
 509 /* Available everywhere.  */
 510 static gcov_position_t gcov_position (void);
 511 static int gcov_is_error (void);
 512
 513 GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void);
 514 GCOV_LINKAGE gcov_type gcov_read_counter (void);
 515 GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *);
 516
 517 #if IN_LIBGCOV
 518 /* Available only in libgcov */
 519 GCOV_LINKAGE void gcov_write_counter (gcov_type);
 520 GCOV_LINKAGE void gcov_write_tag_length (gcov_unsigned_t, gcov_unsigned_t);
 521 GCOV_LINKAGE void gcov_write_summary (gcov_unsigned_t /*tag*/,
 522                                       const struct gcov_summary *);
 523 static void gcov_rewrite (void);
 524 GCOV_LINKAGE void gcov_seek (gcov_position_t /*position*/);
 525 #else
 526 /* Available outside libgcov */
 527 GCOV_LINKAGE const char *gcov_read_string (void);
 528 GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/,
 529                              gcov_unsigned_t /*length */);
 530 #endif
 531
 532 #if !IN_GCOV
 533 /* Available outside gcov */
 534 GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t);
 535 #endif
 536
 537 #if !IN_GCOV && !IN_LIBGCOV
 538 /* Available only in compiler */
 539 GCOV_LINKAGE void gcov_write_string (const char *);
 540 GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t);
 541 GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/);
 542 #endif
 543
 544 #if IN_GCOV > 0
 545 /* Available in gcov */
 546 GCOV_LINKAGE time_t gcov_time (void);
 547 #endif
 548
 549 /* Make sure the library is used correctly.  */
 550 #if ENABLE_CHECKING
 551 #define GCOV_CHECK(expr) ((expr) ? (void)0 : (void)abort ())
 552 #else
 553 #define GCOV_CHECK(expr)
 554 #endif
 555 #define GCOV_CHECK_READING() GCOV_CHECK(gcov_var.mode > 0)
 556 #define GCOV_CHECK_WRITING() GCOV_CHECK(gcov_var.mode < 0)
 557
 558 /* Save the current position in the gcov file.  */
 559
 560 static inline gcov_position_t
 561 gcov_position (void)
 562 {
 563   GCOV_CHECK_READING ();
 564   return gcov_var.start + gcov_var.offset;
 565 }
 566
 567 /* Return nonzero if the error flag is set.  */
 568
 569 static inline int
 570 gcov_is_error (void)
 571 {
 572   return gcov_var.file ? gcov_var.error : 1;
 573 }
 574
 575 #if IN_LIBGCOV
 576 /* Move to beginning of file and initialize for writing.  */
 577
 578 static inline void
 579 gcov_rewrite (void)
 580 {
 581   GCOV_CHECK_READING ();
 582   gcov_var.mode = -1;
 583   gcov_var.start = 0;
 584   gcov_var.offset = 0;
 585   fseek (gcov_var.file, 0L, SEEK_SET);
 586 }
 587 #endif
 588
 589 #endif /* IN_LIBGCOV >= 0 */
 590
 591 #endif /* GCC_GCOV_IO_H */