gcov-io.h revision 132718
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 7This file is part of GCC. 8 9GCC is free software; you can redistribute it and/or modify it under 10the terms of the GNU General Public License as published by the Free 11Software Foundation; either version 2, or (at your option) any later 12version. 13 14GCC is distributed in the hope that it will be useful, but WITHOUT ANY 15WARRANTY; without even the implied warranty of MERCHANTABILITY or 16FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 17for more details. 18 19You should have received a copy of the GNU General Public License 20along with GCC; see the file COPYING. If not, write to the Free 21Software Foundation, 59 Temple Place - Suite 330, Boston, MA 2202111-1307, 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 33 by the program under test. Both files use a similar structure. We 34 do not attempt to make these files backwards compatible with 35 previous versions, as you only need coverage information when 36 developing a program. We do hold version information, so that 37 mismatches can be detected, and we use a format that allows tools 38 to skip information they do not understand or are not interested 39 in. 40 41 Numbers are recorded in the 32 bit unsigned binary form of the 42 endianness of the machine generating the file. 64 bit numbers are 43 stored as two 32 bit numbers, the low part first. Strings are 44 padded with 1 to 4 NUL bytes, to bring the length up to a multiple 45 of 4. The number of 4 bytes is stored, followed by the padded 46 string. Zero length and NULL strings are simply stored as 47 a length of zero (they have no trailing NUL or padding). 48 49 int32: byte3 byte2 byte1 byte0 | byte0 byte1 byte2 byte3 50 int64: int32:low int32:high 51 string: int32:0 | int32:length char* char:0 padding 52 padding: | char:0 | char:0 char:0 | char:0 char:0 char:0 53 item: int32 | int64 | string 54 55 The basic format of the files is 56 57 file : int32:magic int32:version int32:stamp record* 58 59 The magic ident is different for the notes and the data files. The 60 magic ident is used to determine the endianness of the file, when 61 reading. The version is the same for both files and is derived 62 from gcc's version number. The stamp value is used to synchronize 63 note and data files and to synchronize merging within a data 64 file. It need not be an absolute time stamp, merely a ticker that 65 increments fast enough and cycles slow enough to distinguish 66 different compile/run/compile cycles. 67 68 Although the ident and version are formally 32 bit numbers, they 69 are derived from 4 character ASCII strings. The version number 70 consists of the single character major version number, a two 71 character minor version number (leading zero for versions less than 72 10), and a single character indicating the status of the release. 73 That will be 'e' experimental, 'p' prerelease and 'r' for release. 74 Because, by good fortune, these are in alphabetical order, string 75 collating can be used to compare version strings. Be aware that 76 the 'e' designation will (naturally) be unstable and might be 77 incompatible with itself. For gcc 3.4 experimental, it would be 78 '304e' (0x33303465). When the major version reaches 10, the 79 letters A-Z will be used. Assuming minor increments releases every 80 6 months, we have to make a major increment every 50 years. 81 Assuming major increments releases every 5 years, we're ok for the 82 next 155 years -- good enough for me. 83 84 A record has a tag, length and variable amount of data. 85 86 record: header data 87 header: int32:tag int32:length 88 data: item* 89 90 Records are not nested, but there is a record hierarchy. Tag 91 numbers reflect this hierarchy. Tags are unique across note and 92 data files. Some record types have a varying amount of data. The 93 LENGTH is the number of 4bytes that follow and is usually used to 94 determine how much data. The tag value is split into 4 8-bit 95 fields, one for each of four possible levels. The most significant 96 is allocated first. Unused levels are zero. Active levels are 97 odd-valued, so that the LSB of the level is one. A sub-level 98 incorporates the values of its superlevels. This formatting allows 99 you to determine the tag hierarchy, without understanding the tags 100 themselves, and is similar to the standard section numbering used 101 in technical documents. Level values [1..3f] are used for common 102 tags, values [41..9f] for the notes file and [a1..ff] for the data 103 file. 104 105 The basic block graph file contains the following records 106 note: unit function-graph* 107 unit: header int32:checksum string:source 108 function-graph: announce_function basic_blocks {arcs | lines}* 109 announce_function: header int32:ident int32:checksum 110 string:name string:source int32:lineno 111 basic_block: header int32:flags* 112 arcs: header int32:block_no arc* 113 arc: int32:dest_block int32:flags 114 lines: header int32:block_no line* 115 int32:0 string:NULL 116 line: int32:line_no | int32:0 string:filename 117 118 The BASIC_BLOCK record holds per-bb flags. The number of blocks 119 can be inferred from its data length. There is one ARCS record per 120 basic block. The number of arcs from a bb is implicit from the 121 data length. It enumerates the destination bb and per-arc flags. 122 There is one LINES record per basic block, it enumerates the source 123 lines which belong to that basic block. Source file names are 124 introduced by a line number of 0, following lines are from the new 125 source file. The initial source file for the function is NULL, but 126 the current source file should be remembered from one LINES record 127 to the next. The end of a block is indicated by an empty filename 128 - this does not reset the current source file. Note there is no 129 ordering of the ARCS and LINES records: they may be in any order, 130 interleaved in any manner. The current filename follows the order 131 the LINES records are stored in the file, *not* the ordering of the 132 blocks they are for. 133 134 The data file contains the following records. 135 data: {unit function-data* summary:object summary:program*}* 136 unit: header int32:checksum 137 function-data: announce_function arc_counts 138 announce_function: header int32:ident int32:checksum 139 arc_counts: header int64:count* 140 summary: int32:checksum {count-summary}GCOV_COUNTERS 141 count-summary: int32:num int32:runs int64:sum 142 int64:max int64:sum_max 143 144 The ANNOUNCE_FUNCTION record is the same as that in the note file, 145 but without the source location. The ARC_COUNTS gives the counter 146 values for those arcs that are instrumented. The SUMMARY records 147 give information about the whole object file and about the whole 148 program. The checksum is used for whole program summaries, and 149 disambiguates different programs which include the same 150 instrumented object file. There may be several program summaries, 151 each with a unique checksum. The object summary's checksum is zero. 152 Note that the data file might contain information from several runs 153 concatenated, or the data might be merged. 154 155 This file is included by both the compiler, gcov tools and the 156 runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to 157 distinguish which case is which. If IN_LIBGCOV is nonzero, 158 libgcov is being built. If IN_GCOV is nonzero, the gcov tools are 159 being built. Otherwise the compiler is being built. IN_GCOV may be 160 positive or negative. If positive, we are compiling a tool that 161 requires additional functions (see the code for knowledge of what 162 those functions are). */ 163 164#ifndef GCC_GCOV_IO_H 165#define GCC_GCOV_IO_H 166 167#if IN_LIBGCOV 168/* About the target */ 169 170#if BITS_PER_UNIT == 8 171typedef unsigned gcov_unsigned_t __attribute__ ((mode (SI))); 172typedef unsigned gcov_position_t __attribute__ ((mode (SI))); 173#if LONG_LONG_TYPE_SIZE > 32 174typedef signed gcov_type __attribute__ ((mode (DI))); 175#else 176typedef signed gcov_type __attribute__ ((mode (SI))); 177#endif 178#else 179#if BITS_PER_UNIT == 16 180typedef unsigned gcov_unsigned_t __attribute__ ((mode (HI))); 181typedef unsigned gcov_position_t __attribute__ ((mode (HI))); 182#if LONG_LONG_TYPE_SIZE > 32 183typedef signed gcov_type __attribute__ ((mode (SI))); 184#else 185typedef signed gcov_type __attribute__ ((mode (HI))); 186#endif 187#else 188typedef unsigned gcov_unsigned_t __attribute__ ((mode (QI))); 189typedef unsigned gcov_position_t __attribute__ ((mode (QI))); 190#if LONG_LONG_TYPE_SIZE > 32 191typedef signed gcov_type __attribute__ ((mode (HI))); 192#else 193typedef signed gcov_type __attribute__ ((mode (QI))); 194#endif 195#endif 196#endif 197 198 199#if defined (TARGET_HAS_F_SETLKW) 200#define GCOV_LOCKED 1 201#else 202#define GCOV_LOCKED 0 203#endif 204 205#else /* !IN_LIBGCOV */ 206/* About the host */ 207 208typedef unsigned gcov_unsigned_t; 209typedef unsigned gcov_position_t; 210/* gcov_type is typedef'd elsewhere for the compiler */ 211#if IN_GCOV 212#define GCOV_LINKAGE static 213typedef HOST_WIDEST_INT gcov_type; 214#if IN_GCOV > 0 215#include <sys/types.h> 216#endif 217#else /*!IN_GCOV */ 218#if LONG_LONG_TYPE_SIZE > 32 219#define GCOV_TYPE_NODE intDI_type_node 220#else 221#define GCOV_TYPE_NODE intSI_type_node 222#endif 223#endif 224 225#if defined (HOST_HAS_F_SETLKW) 226#define GCOV_LOCKED 1 227#else 228#define GCOV_LOCKED 0 229#endif 230 231#endif /* !IN_LIBGCOV */ 232 233/* In gcov we want function linkage to be static. In libgcov we need 234 these functions to be extern, so prefix them with __gcov. In the 235 compiler we want it extern, so that they can be accessed from 236 elsewhere. */ 237#if IN_LIBGCOV 238#define gcov_var __gcov_var 239#define gcov_open __gcov_open 240#define gcov_close __gcov_close 241#define gcov_write_tag_length __gcov_write_tag_length 242#define gcov_position __gcov_position 243#define gcov_seek __gcov_seek 244#define gcov_rewrite __gcov_rewrite 245#define gcov_is_error __gcov_is_error 246#define gcov_is_eof __gcov_is_eof 247#define gcov_write_unsigned __gcov_write_unsigned 248#define gcov_write_counter __gcov_write_counter 249#define gcov_write_summary __gcov_write_summary 250#define gcov_read_unsigned __gcov_read_unsigned 251#define gcov_read_counter __gcov_read_counter 252#define gcov_read_summary __gcov_read_summary 253 254/* Poison these, so they don't accidentally slip in. */ 255#pragma GCC poison gcov_write_string gcov_write_tag gcov_write_length 256#pragma GCC poison gcov_read_string gcov_sync gcov_time gcov_magic 257 258#endif 259 260#ifndef GCOV_LINKAGE 261#define GCOV_LINKAGE extern 262#endif 263 264/* File suffixes. */ 265#define GCOV_DATA_SUFFIX ".gcda" 266#define GCOV_NOTE_SUFFIX ".gcno" 267 268/* File magic. Must not be palindromes. */ 269#define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */ 270#define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */ 271 272/* gcov-iov.h is automatically generated by the makefile from 273 version.c, it looks like 274 #define GCOV_VERSION ((gcov_unsigned_t)0x89abcdef) 275*/ 276#include "gcov-iov.h" 277 278/* Convert a magic or version number to a 4 character string. */ 279#define GCOV_UNSIGNED2STRING(ARRAY,VALUE) \ 280 ((ARRAY)[0] = (char)((VALUE) >> 24), \ 281 (ARRAY)[1] = (char)((VALUE) >> 16), \ 282 (ARRAY)[2] = (char)((VALUE) >> 8), \ 283 (ARRAY)[3] = (char)((VALUE) >> 0)) 284 285/* The record tags. Values [1..3f] are for tags which may be in either 286 file. Values [41..9f] for those in the note file and [a1..ff] for 287 the data file. */ 288 289#define GCOV_TAG_FUNCTION ((gcov_unsigned_t)0x01000000) 290#define GCOV_TAG_FUNCTION_LENGTH (2) 291#define GCOV_TAG_BLOCKS ((gcov_unsigned_t)0x01410000) 292#define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM) 293#define GCOV_TAG_BLOCKS_NUM(LENGTH) (LENGTH) 294#define GCOV_TAG_ARCS ((gcov_unsigned_t)0x01430000) 295#define GCOV_TAG_ARCS_LENGTH(NUM) (1 + (NUM) * 2) 296#define GCOV_TAG_ARCS_NUM(LENGTH) (((LENGTH) - 1) / 2) 297#define GCOV_TAG_LINES ((gcov_unsigned_t)0x01450000) 298#define GCOV_TAG_COUNTER_BASE ((gcov_unsigned_t)0x01a10000) 299#define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2) 300#define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2) 301#define GCOV_TAG_OBJECT_SUMMARY ((gcov_unsigned_t)0xa1000000) 302#define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000) 303#define GCOV_TAG_SUMMARY_LENGTH \ 304 (1 + GCOV_COUNTERS_SUMMABLE * (2 + 3 * 2)) 305 306/* Counters that are collected. */ 307#define GCOV_COUNTER_ARCS 0 /* Arc transitions. */ 308#define GCOV_COUNTERS_SUMMABLE 1 /* Counters which can be 309 summaried. */ 310#define GCOV_FIRST_VALUE_COUNTER 1 /* The first of counters used for value 311 profiling. They must form a consecutive 312 interval and their order must match 313 the order of HIST_TYPEs in 314 value-prof.h. */ 315#define GCOV_COUNTER_V_INTERVAL 1 /* Histogram of value inside an interval. */ 316#define GCOV_COUNTER_V_POW2 2 /* Histogram of exact power2 logarithm 317 of a value. */ 318#define GCOV_COUNTER_V_SINGLE 3 /* The most common value of expression. */ 319#define GCOV_COUNTER_V_DELTA 4 /* The most common difference between 320 consecutive values of expression. */ 321#define GCOV_LAST_VALUE_COUNTER 4 /* The last of counters used for value 322 profiling. */ 323#define GCOV_COUNTERS 5 324 325/* Number of counters used for value profiling. */ 326#define GCOV_N_VALUE_COUNTERS \ 327 (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1) 328 329 /* A list of human readable names of the counters */ 330#define GCOV_COUNTER_NAMES {"arcs", "interval", "pow2", "single", "delta"} 331 332 /* Names of merge functions for counters. */ 333#define GCOV_MERGE_FUNCTIONS {"__gcov_merge_add", \ 334 "__gcov_merge_add", \ 335 "__gcov_merge_add", \ 336 "__gcov_merge_single", \ 337 "__gcov_merge_delta"} 338 339/* Convert a counter index to a tag. */ 340#define GCOV_TAG_FOR_COUNTER(COUNT) \ 341 (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17)) 342/* Convert a tag to a counter. */ 343#define GCOV_COUNTER_FOR_TAG(TAG) \ 344 ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17)) 345/* Check whether a tag is a counter tag. */ 346#define GCOV_TAG_IS_COUNTER(TAG) \ 347 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS) 348 349/* The tag level mask has 1's in the position of the inner levels, & 350 the lsb of the current level, and zero on the current and outer 351 levels. */ 352#define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG)) 353 354/* Return nonzero if SUB is an immediate subtag of TAG. */ 355#define GCOV_TAG_IS_SUBTAG(TAG,SUB) \ 356 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \ 357 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK(TAG))) 358 359/* Return nonzero if SUB is at a sublevel to TAG. */ 360#define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \ 361 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB)) 362 363/* Basic block flags. */ 364#define GCOV_BLOCK_UNEXPECTED (1 << 1) 365 366/* Arc flags. */ 367#define GCOV_ARC_ON_TREE (1 << 0) 368#define GCOV_ARC_FAKE (1 << 1) 369#define GCOV_ARC_FALLTHROUGH (1 << 2) 370 371/* Structured records. */ 372 373/* Cumulative counter data. */ 374struct gcov_ctr_summary 375{ 376 gcov_unsigned_t num; /* number of counters. */ 377 gcov_unsigned_t runs; /* number of program runs */ 378 gcov_type sum_all; /* sum of all counters accumulated. */ 379 gcov_type run_max; /* maximum value on a single run. */ 380 gcov_type sum_max; /* sum of individual run max values. */ 381}; 382 383/* Object & program summary record. */ 384struct gcov_summary 385{ 386 gcov_unsigned_t checksum; /* checksum of program */ 387 struct gcov_ctr_summary ctrs[GCOV_COUNTERS_SUMMABLE]; 388}; 389 390/* Structures embedded in coveraged program. The structures generated 391 by write_profile must match these. */ 392 393#if IN_LIBGCOV 394/* Information about a single function. This uses the trailing array 395 idiom. The number of counters is determined from the counter_mask 396 in gcov_info. We hold an array of function info, so have to 397 explicitly calculate the correct array stride. */ 398struct gcov_fn_info 399{ 400 gcov_unsigned_t ident; /* unique ident of function */ 401 gcov_unsigned_t checksum; /* function checksum */ 402 unsigned n_ctrs[0]; /* instrumented counters */ 403}; 404 405/* Type of function used to merge counters. */ 406typedef void (*gcov_merge_fn) (gcov_type *, gcov_unsigned_t); 407 408/* Information about counters. */ 409struct gcov_ctr_info 410{ 411 gcov_unsigned_t num; /* number of counters. */ 412 gcov_type *values; /* their values. */ 413 gcov_merge_fn merge; /* The function used to merge them. */ 414}; 415 416/* Information about a single object file. */ 417struct gcov_info 418{ 419 gcov_unsigned_t version; /* expected version number */ 420 struct gcov_info *next; /* link to next, used by libgcov */ 421 422 gcov_unsigned_t stamp; /* uniquifying time stamp */ 423 const char *filename; /* output file name */ 424 425 unsigned n_functions; /* number of functions */ 426 const struct gcov_fn_info *functions; /* table of functions */ 427 428 unsigned ctr_mask; /* mask of counters instrumented. */ 429 struct gcov_ctr_info counts[0]; /* count data. The number of bits 430 set in the ctr_mask field 431 determines how big this array 432 is. */ 433}; 434 435/* Register a new object file module. */ 436extern void __gcov_init (struct gcov_info *); 437 438/* Called before fork, to avoid double counting. */ 439extern void __gcov_flush (void); 440 441/* The merge function that just sums the counters. */ 442extern void __gcov_merge_add (gcov_type *, unsigned); 443 444/* The merge function to choose the most common value. */ 445extern void __gcov_merge_single (gcov_type *, unsigned); 446 447/* The merge function to choose the most common difference between 448 consecutive values. */ 449extern void __gcov_merge_delta (gcov_type *, unsigned); 450#endif /* IN_LIBGCOV */ 451 452#if IN_LIBGCOV >= 0 453 454/* Optimum number of gcov_unsigned_t's read from or written to disk. */ 455#define GCOV_BLOCK_SIZE (1 << 10) 456 457GCOV_LINKAGE struct gcov_var 458{ 459 FILE *file; 460 gcov_position_t start; /* Position of first byte of block */ 461 unsigned offset; /* Read/write position within the block. */ 462 unsigned length; /* Read limit in the block. */ 463 unsigned overread; /* Number of words overread. */ 464 int error; /* < 0 overflow, > 0 disk error. */ 465 int mode; /* < 0 writing, > 0 reading */ 466#if IN_LIBGCOV 467 /* Holds one block plus 4 bytes, thus all coverage reads & writes 468 fit within this buffer and we always can transfer GCOV_BLOCK_SIZE 469 to and from the disk. libgcov never backtracks and only writes 4 470 or 8 byte objects. */ 471 gcov_unsigned_t buffer[GCOV_BLOCK_SIZE + 1]; 472#else 473 int endian; /* Swap endianness. */ 474 /* Holds a variable length block, as the compiler can write 475 strings and needs to backtrack. */ 476 size_t alloc; 477 gcov_unsigned_t *buffer; 478#endif 479} gcov_var; 480 481/* Functions for reading and writing gcov files. In libgcov you can 482 open the file for reading then writing. Elsewhere you can open the 483 file either for reading or for writing. When reading a file you may 484 use the gcov_read_* functions, gcov_sync, gcov_position, & 485 gcov_error. When writing a file you may use the gcov_write 486 functions, gcov_seek & gcov_error. When a file is to be rewritten 487 you use the functions for reading, then gcov_rewrite then the 488 functions for writing. Your file may become corrupted if you break 489 these invariants. */ 490#if IN_LIBGCOV 491GCOV_LINKAGE int gcov_open (const char */*name*/); 492#else 493GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/); 494GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t); 495#endif 496GCOV_LINKAGE int gcov_close (void); 497 498/* Available everywhere. */ 499static gcov_position_t gcov_position (void); 500static int gcov_is_error (void); 501static int gcov_is_eof (void); 502 503GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void); 504GCOV_LINKAGE gcov_type gcov_read_counter (void); 505GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *); 506 507#if IN_LIBGCOV 508/* Available only in libgcov */ 509GCOV_LINKAGE void gcov_write_counter (gcov_type); 510GCOV_LINKAGE void gcov_write_tag_length (gcov_unsigned_t, gcov_unsigned_t); 511GCOV_LINKAGE void gcov_write_summary (gcov_unsigned_t /*tag*/, 512 const struct gcov_summary *); 513static void gcov_truncate (void); 514static void gcov_rewrite (void); 515GCOV_LINKAGE void gcov_seek (gcov_position_t /*position*/); 516#else 517/* Available outside libgcov */ 518GCOV_LINKAGE const char *gcov_read_string (void); 519GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/, 520 gcov_unsigned_t /*length */); 521#endif 522 523#if !IN_GCOV 524/* Available outside gcov */ 525GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t); 526#endif 527 528#if !IN_GCOV && !IN_LIBGCOV 529/* Available only in compiler */ 530GCOV_LINKAGE void gcov_write_string (const char *); 531GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t); 532GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/); 533#endif 534 535#if IN_GCOV > 0 536/* Available in gcov */ 537GCOV_LINKAGE time_t gcov_time (void); 538#endif 539 540/* Make sure the library is used correctly. */ 541#if ENABLE_CHECKING 542#define GCOV_CHECK(expr) ((expr) ? (void)0 : (void)abort ()) 543#else 544#define GCOV_CHECK(expr) 545#endif 546#define GCOV_CHECK_READING() GCOV_CHECK(gcov_var.mode > 0) 547#define GCOV_CHECK_WRITING() GCOV_CHECK(gcov_var.mode < 0) 548 549/* Save the current position in the gcov file. */ 550 551static inline gcov_position_t 552gcov_position (void) 553{ 554 GCOV_CHECK_READING (); 555 return gcov_var.start + gcov_var.offset; 556} 557 558/* Return nonzero if we read to end of file. */ 559 560static inline int 561gcov_is_eof (void) 562{ 563 return !gcov_var.overread; 564} 565 566/* Return nonzero if the error flag is set. */ 567 568static inline int 569gcov_is_error (void) 570{ 571 return gcov_var.file ? gcov_var.error : 1; 572} 573 574#if IN_LIBGCOV 575/* Move to beginning of file and initialize for writing. */ 576 577static inline void 578gcov_rewrite (void) 579{ 580 GCOV_CHECK_READING (); 581 gcov_var.mode = -1; 582 gcov_var.start = 0; 583 gcov_var.offset = 0; 584 fseek (gcov_var.file, 0L, SEEK_SET); 585} 586 587#ifdef __MINGW32__ 588#define ftruncate _chsize 589#endif 590static inline void 591gcov_truncate (void) 592{ 593 ftruncate (fileno (gcov_var.file), 0L); 594} 595#endif 596 597#endif /* IN_LIBGCOV >= 0 */ 598 599#endif /* GCC_GCOV_IO_H */ 600