1//===--- raw_ostream.cpp - Implement the raw_ostream classes --------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This implements support for bulk buffered stream output. 11// 12//===----------------------------------------------------------------------===// 13 14#include "llvm/Support/raw_ostream.h" 15#include "llvm/Support/Format.h" 16#include "llvm/Support/Program.h" 17#include "llvm/Support/Process.h" 18#include "llvm/ADT/StringExtras.h" 19#include "llvm/ADT/SmallVector.h" 20#include "llvm/Config/config.h" 21#include "llvm/Support/Compiler.h" 22#include "llvm/Support/ErrorHandling.h" 23#include "llvm/Support/system_error.h" 24#include "llvm/ADT/STLExtras.h" 25#include <cctype> 26#include <cerrno> 27#include <sys/stat.h> 28#include <sys/types.h> 29 30#if defined(HAVE_UNISTD_H) 31# include <unistd.h> 32#endif 33#if defined(HAVE_FCNTL_H) 34# include <fcntl.h> 35#endif 36#if defined(HAVE_SYS_UIO_H) && defined(HAVE_WRITEV) 37# include <sys/uio.h> 38#endif 39 40#if defined(__CYGWIN__) 41#include <io.h> 42#endif 43 44#if defined(_MSC_VER) 45#include <io.h> 46#include <fcntl.h> 47#ifndef STDIN_FILENO 48# define STDIN_FILENO 0 49#endif 50#ifndef STDOUT_FILENO 51# define STDOUT_FILENO 1 52#endif 53#ifndef STDERR_FILENO 54# define STDERR_FILENO 2 55#endif 56#endif 57 58using namespace llvm; 59 60raw_ostream::~raw_ostream() { 61 // raw_ostream's subclasses should take care to flush the buffer 62 // in their destructors. 63 assert(OutBufCur == OutBufStart && 64 "raw_ostream destructor called with non-empty buffer!"); 65 66 if (BufferMode == InternalBuffer) 67 delete [] OutBufStart; 68} 69 70// An out of line virtual method to provide a home for the class vtable. 71void raw_ostream::handle() {} 72 73size_t raw_ostream::preferred_buffer_size() const { 74 // BUFSIZ is intended to be a reasonable default. 75 return BUFSIZ; 76} 77 78void raw_ostream::SetBuffered() { 79 // Ask the subclass to determine an appropriate buffer size. 80 if (size_t Size = preferred_buffer_size()) 81 SetBufferSize(Size); 82 else 83 // It may return 0, meaning this stream should be unbuffered. 84 SetUnbuffered(); 85} 86 87void raw_ostream::SetBufferAndMode(char *BufferStart, size_t Size, 88 BufferKind Mode) { 89 assert(((Mode == Unbuffered && BufferStart == 0 && Size == 0) || 90 (Mode != Unbuffered && BufferStart && Size)) && 91 "stream must be unbuffered or have at least one byte"); 92 // Make sure the current buffer is free of content (we can't flush here; the 93 // child buffer management logic will be in write_impl). 94 assert(GetNumBytesInBuffer() == 0 && "Current buffer is non-empty!"); 95 96 if (BufferMode == InternalBuffer) 97 delete [] OutBufStart; 98 OutBufStart = BufferStart; 99 OutBufEnd = OutBufStart+Size; 100 OutBufCur = OutBufStart; 101 BufferMode = Mode; 102 103 assert(OutBufStart <= OutBufEnd && "Invalid size!"); 104} 105 106raw_ostream &raw_ostream::operator<<(unsigned long N) { 107 // Zero is a special case. 108 if (N == 0) 109 return *this << '0'; 110 111 char NumberBuffer[20]; 112 char *EndPtr = NumberBuffer+sizeof(NumberBuffer); 113 char *CurPtr = EndPtr; 114 115 while (N) { 116 *--CurPtr = '0' + char(N % 10); 117 N /= 10; 118 } 119 return write(CurPtr, EndPtr-CurPtr); 120} 121 122raw_ostream &raw_ostream::operator<<(long N) { 123 if (N < 0) { 124 *this << '-'; 125 // Avoid undefined behavior on LONG_MIN with a cast. 126 N = -(unsigned long)N; 127 } 128 129 return this->operator<<(static_cast<unsigned long>(N)); 130} 131 132raw_ostream &raw_ostream::operator<<(unsigned long long N) { 133 // Output using 32-bit div/mod when possible. 134 if (N == static_cast<unsigned long>(N)) 135 return this->operator<<(static_cast<unsigned long>(N)); 136 137 char NumberBuffer[20]; 138 char *EndPtr = NumberBuffer+sizeof(NumberBuffer); 139 char *CurPtr = EndPtr; 140 141 while (N) { 142 *--CurPtr = '0' + char(N % 10); 143 N /= 10; 144 } 145 return write(CurPtr, EndPtr-CurPtr); 146} 147 148raw_ostream &raw_ostream::operator<<(long long N) { 149 if (N < 0) { 150 *this << '-'; 151 // Avoid undefined behavior on INT64_MIN with a cast. 152 N = -(unsigned long long)N; 153 } 154 155 return this->operator<<(static_cast<unsigned long long>(N)); 156} 157 158raw_ostream &raw_ostream::write_hex(unsigned long long N) { 159 // Zero is a special case. 160 if (N == 0) 161 return *this << '0'; 162 163 char NumberBuffer[20]; 164 char *EndPtr = NumberBuffer+sizeof(NumberBuffer); 165 char *CurPtr = EndPtr; 166 167 while (N) { 168 uintptr_t x = N % 16; 169 *--CurPtr = (x < 10 ? '0' + x : 'a' + x - 10); 170 N /= 16; 171 } 172 173 return write(CurPtr, EndPtr-CurPtr); 174} 175 176raw_ostream &raw_ostream::write_escaped(StringRef Str, 177 bool UseHexEscapes) { 178 for (unsigned i = 0, e = Str.size(); i != e; ++i) { 179 unsigned char c = Str[i]; 180 181 switch (c) { 182 case '\\': 183 *this << '\\' << '\\'; 184 break; 185 case '\t': 186 *this << '\\' << 't'; 187 break; 188 case '\n': 189 *this << '\\' << 'n'; 190 break; 191 case '"': 192 *this << '\\' << '"'; 193 break; 194 default: 195 if (std::isprint(c)) { 196 *this << c; 197 break; 198 } 199 200 // Write out the escaped representation. 201 if (UseHexEscapes) { 202 *this << '\\' << 'x'; 203 *this << hexdigit((c >> 4 & 0xF)); 204 *this << hexdigit((c >> 0) & 0xF); 205 } else { 206 // Always use a full 3-character octal escape. 207 *this << '\\'; 208 *this << char('0' + ((c >> 6) & 7)); 209 *this << char('0' + ((c >> 3) & 7)); 210 *this << char('0' + ((c >> 0) & 7)); 211 } 212 } 213 } 214 215 return *this; 216} 217 218raw_ostream &raw_ostream::operator<<(const void *P) { 219 *this << '0' << 'x'; 220 221 return write_hex((uintptr_t) P); 222} 223 224raw_ostream &raw_ostream::operator<<(double N) { 225#ifdef _WIN32 226 // On MSVCRT and compatible, output of %e is incompatible to Posix 227 // by default. Number of exponent digits should be at least 2. "%+03d" 228 // FIXME: Implement our formatter to here or Support/Format.h! 229 int fpcl = _fpclass(N); 230 231 // negative zero 232 if (fpcl == _FPCLASS_NZ) 233 return *this << "-0.000000e+00"; 234 235 char buf[16]; 236 unsigned len; 237 len = snprintf(buf, sizeof(buf), "%e", N); 238 if (len <= sizeof(buf) - 2) { 239 if (len >= 5 && buf[len - 5] == 'e' && buf[len - 3] == '0') { 240 int cs = buf[len - 4]; 241 if (cs == '+' || cs == '-') { 242 int c1 = buf[len - 2]; 243 int c0 = buf[len - 1]; 244 if (isdigit(c1) && isdigit(c0)) { 245 // Trim leading '0': "...e+012" -> "...e+12\0" 246 buf[len - 3] = c1; 247 buf[len - 2] = c0; 248 buf[--len] = 0; 249 } 250 } 251 } 252 return this->operator<<(buf); 253 } 254#endif 255 return this->operator<<(format("%e", N)); 256} 257 258 259 260void raw_ostream::flush_nonempty() { 261 assert(OutBufCur > OutBufStart && "Invalid call to flush_nonempty."); 262 size_t Length = OutBufCur - OutBufStart; 263 OutBufCur = OutBufStart; 264 write_impl(OutBufStart, Length); 265} 266 267raw_ostream &raw_ostream::write(unsigned char C) { 268 // Group exceptional cases into a single branch. 269 if (LLVM_UNLIKELY(OutBufCur >= OutBufEnd)) { 270 if (LLVM_UNLIKELY(!OutBufStart)) { 271 if (BufferMode == Unbuffered) { 272 write_impl(reinterpret_cast<char*>(&C), 1); 273 return *this; 274 } 275 // Set up a buffer and start over. 276 SetBuffered(); 277 return write(C); 278 } 279 280 flush_nonempty(); 281 } 282 283 *OutBufCur++ = C; 284 return *this; 285} 286 287raw_ostream &raw_ostream::write(const char *Ptr, size_t Size) { 288 // Group exceptional cases into a single branch. 289 if (LLVM_UNLIKELY(size_t(OutBufEnd - OutBufCur) < Size)) { 290 if (LLVM_UNLIKELY(!OutBufStart)) { 291 if (BufferMode == Unbuffered) { 292 write_impl(Ptr, Size); 293 return *this; 294 } 295 // Set up a buffer and start over. 296 SetBuffered(); 297 return write(Ptr, Size); 298 } 299 300 size_t NumBytes = OutBufEnd - OutBufCur; 301 302 // If the buffer is empty at this point we have a string that is larger 303 // than the buffer. Directly write the chunk that is a multiple of the 304 // preferred buffer size and put the remainder in the buffer. 305 if (LLVM_UNLIKELY(OutBufCur == OutBufStart)) { 306 size_t BytesToWrite = Size - (Size % NumBytes); 307 write_impl(Ptr, BytesToWrite); 308 copy_to_buffer(Ptr + BytesToWrite, Size - BytesToWrite); 309 return *this; 310 } 311 312 // We don't have enough space in the buffer to fit the string in. Insert as 313 // much as possible, flush and start over with the remainder. 314 copy_to_buffer(Ptr, NumBytes); 315 flush_nonempty(); 316 return write(Ptr + NumBytes, Size - NumBytes); 317 } 318 319 copy_to_buffer(Ptr, Size); 320 321 return *this; 322} 323 324void raw_ostream::copy_to_buffer(const char *Ptr, size_t Size) { 325 assert(Size <= size_t(OutBufEnd - OutBufCur) && "Buffer overrun!"); 326 327 // Handle short strings specially, memcpy isn't very good at very short 328 // strings. 329 switch (Size) { 330 case 4: OutBufCur[3] = Ptr[3]; // FALL THROUGH 331 case 3: OutBufCur[2] = Ptr[2]; // FALL THROUGH 332 case 2: OutBufCur[1] = Ptr[1]; // FALL THROUGH 333 case 1: OutBufCur[0] = Ptr[0]; // FALL THROUGH 334 case 0: break; 335 default: 336 memcpy(OutBufCur, Ptr, Size); 337 break; 338 } 339 340 OutBufCur += Size; 341} 342 343// Formatted output. 344raw_ostream &raw_ostream::operator<<(const format_object_base &Fmt) { 345 // If we have more than a few bytes left in our output buffer, try 346 // formatting directly onto its end. 347 size_t NextBufferSize = 127; 348 size_t BufferBytesLeft = OutBufEnd - OutBufCur; 349 if (BufferBytesLeft > 3) { 350 size_t BytesUsed = Fmt.print(OutBufCur, BufferBytesLeft); 351 352 // Common case is that we have plenty of space. 353 if (BytesUsed <= BufferBytesLeft) { 354 OutBufCur += BytesUsed; 355 return *this; 356 } 357 358 // Otherwise, we overflowed and the return value tells us the size to try 359 // again with. 360 NextBufferSize = BytesUsed; 361 } 362 363 // If we got here, we didn't have enough space in the output buffer for the 364 // string. Try printing into a SmallVector that is resized to have enough 365 // space. Iterate until we win. 366 SmallVector<char, 128> V; 367 368 while (1) { 369 V.resize(NextBufferSize); 370 371 // Try formatting into the SmallVector. 372 size_t BytesUsed = Fmt.print(V.data(), NextBufferSize); 373 374 // If BytesUsed fit into the vector, we win. 375 if (BytesUsed <= NextBufferSize) 376 return write(V.data(), BytesUsed); 377 378 // Otherwise, try again with a new size. 379 assert(BytesUsed > NextBufferSize && "Didn't grow buffer!?"); 380 NextBufferSize = BytesUsed; 381 } 382} 383 384/// indent - Insert 'NumSpaces' spaces. 385raw_ostream &raw_ostream::indent(unsigned NumSpaces) { 386 static const char Spaces[] = " " 387 " " 388 " "; 389 390 // Usually the indentation is small, handle it with a fastpath. 391 if (NumSpaces < array_lengthof(Spaces)) 392 return write(Spaces, NumSpaces); 393 394 while (NumSpaces) { 395 unsigned NumToWrite = std::min(NumSpaces, 396 (unsigned)array_lengthof(Spaces)-1); 397 write(Spaces, NumToWrite); 398 NumSpaces -= NumToWrite; 399 } 400 return *this; 401} 402 403 404//===----------------------------------------------------------------------===// 405// Formatted Output 406//===----------------------------------------------------------------------===// 407 408// Out of line virtual method. 409void format_object_base::home() { 410} 411 412//===----------------------------------------------------------------------===// 413// raw_fd_ostream 414//===----------------------------------------------------------------------===// 415 416/// raw_fd_ostream - Open the specified file for writing. If an error 417/// occurs, information about the error is put into ErrorInfo, and the 418/// stream should be immediately destroyed; the string will be empty 419/// if no error occurred. 420raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo, 421 unsigned Flags) 422 : Error(false), UseAtomicWrites(false), pos(0) 423{ 424 assert(Filename != 0 && "Filename is null"); 425 // Verify that we don't have both "append" and "excl". 426 assert((!(Flags & F_Excl) || !(Flags & F_Append)) && 427 "Cannot specify both 'excl' and 'append' file creation flags!"); 428 429 ErrorInfo.clear(); 430 431 // Handle "-" as stdout. Note that when we do this, we consider ourself 432 // the owner of stdout. This means that we can do things like close the 433 // file descriptor when we're done and set the "binary" flag globally. 434 if (Filename[0] == '-' && Filename[1] == 0) { 435 FD = STDOUT_FILENO; 436 // If user requested binary then put stdout into binary mode if 437 // possible. 438 if (Flags & F_Binary) 439 sys::Program::ChangeStdoutToBinary(); 440 // Close stdout when we're done, to detect any output errors. 441 ShouldClose = true; 442 return; 443 } 444 445 int OpenFlags = O_WRONLY|O_CREAT; 446#ifdef O_BINARY 447 if (Flags & F_Binary) 448 OpenFlags |= O_BINARY; 449#endif 450 451 if (Flags & F_Append) 452 OpenFlags |= O_APPEND; 453 else 454 OpenFlags |= O_TRUNC; 455 if (Flags & F_Excl) 456 OpenFlags |= O_EXCL; 457 458 while ((FD = open(Filename, OpenFlags, 0664)) < 0) { 459 if (errno != EINTR) { 460 ErrorInfo = "Error opening output file '" + std::string(Filename) + "'"; 461 ShouldClose = false; 462 return; 463 } 464 } 465 466 // Ok, we successfully opened the file, so it'll need to be closed. 467 ShouldClose = true; 468} 469 470/// raw_fd_ostream ctor - FD is the file descriptor that this writes to. If 471/// ShouldClose is true, this closes the file when the stream is destroyed. 472raw_fd_ostream::raw_fd_ostream(int fd, bool shouldClose, bool unbuffered) 473 : raw_ostream(unbuffered), FD(fd), 474 ShouldClose(shouldClose), Error(false), UseAtomicWrites(false) { 475#ifdef O_BINARY 476 // Setting STDOUT and STDERR to binary mode is necessary in Win32 477 // to avoid undesirable linefeed conversion. 478 if (fd == STDOUT_FILENO || fd == STDERR_FILENO) 479 setmode(fd, O_BINARY); 480#endif 481 482 // Get the starting position. 483 off_t loc = ::lseek(FD, 0, SEEK_CUR); 484 if (loc == (off_t)-1) 485 pos = 0; 486 else 487 pos = static_cast<uint64_t>(loc); 488} 489 490raw_fd_ostream::~raw_fd_ostream() { 491 if (FD >= 0) { 492 flush(); 493 if (ShouldClose) 494 while (::close(FD) != 0) 495 if (errno != EINTR) { 496 error_detected(); 497 break; 498 } 499 } 500 501#ifdef __MINGW32__ 502 // On mingw, global dtors should not call exit(). 503 // report_fatal_error() invokes exit(). We know report_fatal_error() 504 // might not write messages to stderr when any errors were detected 505 // on FD == 2. 506 if (FD == 2) return; 507#endif 508 509 // If there are any pending errors, report them now. Clients wishing 510 // to avoid report_fatal_error calls should check for errors with 511 // has_error() and clear the error flag with clear_error() before 512 // destructing raw_ostream objects which may have errors. 513 if (has_error()) 514 report_fatal_error("IO failure on output stream."); 515} 516 517 518void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) { 519 assert(FD >= 0 && "File already closed."); 520 pos += Size; 521 522 do { 523 ssize_t ret; 524 525 // Check whether we should attempt to use atomic writes. 526 if (LLVM_LIKELY(!UseAtomicWrites)) { 527 ret = ::write(FD, Ptr, Size); 528 } else { 529 // Use ::writev() where available. 530#if defined(HAVE_WRITEV) 531 const void *Addr = static_cast<const void *>(Ptr); 532 struct iovec IOV = {const_cast<void *>(Addr), Size }; 533 ret = ::writev(FD, &IOV, 1); 534#else 535 ret = ::write(FD, Ptr, Size); 536#endif 537 } 538 539 if (ret < 0) { 540 // If it's a recoverable error, swallow it and retry the write. 541 // 542 // Ideally we wouldn't ever see EAGAIN or EWOULDBLOCK here, since 543 // raw_ostream isn't designed to do non-blocking I/O. However, some 544 // programs, such as old versions of bjam, have mistakenly used 545 // O_NONBLOCK. For compatibility, emulate blocking semantics by 546 // spinning until the write succeeds. If you don't want spinning, 547 // don't use O_NONBLOCK file descriptors with raw_ostream. 548 if (errno == EINTR || errno == EAGAIN 549#ifdef EWOULDBLOCK 550 || errno == EWOULDBLOCK 551#endif 552 ) 553 continue; 554 555 // Otherwise it's a non-recoverable error. Note it and quit. 556 error_detected(); 557 break; 558 } 559 560 // The write may have written some or all of the data. Update the 561 // size and buffer pointer to reflect the remainder that needs 562 // to be written. If there are no bytes left, we're done. 563 Ptr += ret; 564 Size -= ret; 565 } while (Size > 0); 566} 567 568void raw_fd_ostream::close() { 569 assert(ShouldClose); 570 ShouldClose = false; 571 flush(); 572 while (::close(FD) != 0) 573 if (errno != EINTR) { 574 error_detected(); 575 break; 576 } 577 FD = -1; 578} 579 580uint64_t raw_fd_ostream::seek(uint64_t off) { 581 flush(); 582 pos = ::lseek(FD, off, SEEK_SET); 583 if (pos != off) 584 error_detected(); 585 return pos; 586} 587 588size_t raw_fd_ostream::preferred_buffer_size() const { 589#if !defined(_MSC_VER) && !defined(__MINGW32__) && !defined(__minix) 590 // Windows and Minix have no st_blksize. 591 assert(FD >= 0 && "File not yet open!"); 592 struct stat statbuf; 593 if (fstat(FD, &statbuf) != 0) 594 return 0; 595 596 // If this is a terminal, don't use buffering. Line buffering 597 // would be a more traditional thing to do, but it's not worth 598 // the complexity. 599 if (S_ISCHR(statbuf.st_mode) && isatty(FD)) 600 return 0; 601 // Return the preferred block size. 602 return statbuf.st_blksize; 603#else 604 return raw_ostream::preferred_buffer_size(); 605#endif 606} 607 608raw_ostream &raw_fd_ostream::changeColor(enum Colors colors, bool bold, 609 bool bg) { 610 if (sys::Process::ColorNeedsFlush()) 611 flush(); 612 const char *colorcode = 613 (colors == SAVEDCOLOR) ? sys::Process::OutputBold(bg) 614 : sys::Process::OutputColor(colors, bold, bg); 615 if (colorcode) { 616 size_t len = strlen(colorcode); 617 write(colorcode, len); 618 // don't account colors towards output characters 619 pos -= len; 620 } 621 return *this; 622} 623 624raw_ostream &raw_fd_ostream::resetColor() { 625 if (sys::Process::ColorNeedsFlush()) 626 flush(); 627 const char *colorcode = sys::Process::ResetColor(); 628 if (colorcode) { 629 size_t len = strlen(colorcode); 630 write(colorcode, len); 631 // don't account colors towards output characters 632 pos -= len; 633 } 634 return *this; 635} 636 637raw_ostream &raw_fd_ostream::reverseColor() { 638 if (sys::Process::ColorNeedsFlush()) 639 flush(); 640 const char *colorcode = sys::Process::OutputReverse(); 641 if (colorcode) { 642 size_t len = strlen(colorcode); 643 write(colorcode, len); 644 // don't account colors towards output characters 645 pos -= len; 646 } 647 return *this; 648} 649 650bool raw_fd_ostream::is_displayed() const { 651 return sys::Process::FileDescriptorIsDisplayed(FD); 652} 653 654bool raw_fd_ostream::has_colors() const { 655 return sys::Process::FileDescriptorHasColors(FD); 656} 657 658//===----------------------------------------------------------------------===// 659// outs(), errs(), nulls() 660//===----------------------------------------------------------------------===// 661 662/// outs() - This returns a reference to a raw_ostream for standard output. 663/// Use it like: outs() << "foo" << "bar"; 664raw_ostream &llvm::outs() { 665 // Set buffer settings to model stdout behavior. 666 // Delete the file descriptor when the program exists, forcing error 667 // detection. If you don't want this behavior, don't use outs(). 668 static raw_fd_ostream S(STDOUT_FILENO, true); 669 return S; 670} 671 672/// errs() - This returns a reference to a raw_ostream for standard error. 673/// Use it like: errs() << "foo" << "bar"; 674raw_ostream &llvm::errs() { 675 // Set standard error to be unbuffered by default. 676 static raw_fd_ostream S(STDERR_FILENO, false, true); 677 return S; 678} 679 680/// nulls() - This returns a reference to a raw_ostream which discards output. 681raw_ostream &llvm::nulls() { 682 static raw_null_ostream S; 683 return S; 684} 685 686 687//===----------------------------------------------------------------------===// 688// raw_string_ostream 689//===----------------------------------------------------------------------===// 690 691raw_string_ostream::~raw_string_ostream() { 692 flush(); 693} 694 695void raw_string_ostream::write_impl(const char *Ptr, size_t Size) { 696 OS.append(Ptr, Size); 697} 698 699//===----------------------------------------------------------------------===// 700// raw_svector_ostream 701//===----------------------------------------------------------------------===// 702 703// The raw_svector_ostream implementation uses the SmallVector itself as the 704// buffer for the raw_ostream. We guarantee that the raw_ostream buffer is 705// always pointing past the end of the vector, but within the vector 706// capacity. This allows raw_ostream to write directly into the correct place, 707// and we only need to set the vector size when the data is flushed. 708 709raw_svector_ostream::raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) { 710 // Set up the initial external buffer. We make sure that the buffer has at 711 // least 128 bytes free; raw_ostream itself only requires 64, but we want to 712 // make sure that we don't grow the buffer unnecessarily on destruction (when 713 // the data is flushed). See the FIXME below. 714 OS.reserve(OS.size() + 128); 715 SetBuffer(OS.end(), OS.capacity() - OS.size()); 716} 717 718raw_svector_ostream::~raw_svector_ostream() { 719 // FIXME: Prevent resizing during this flush(). 720 flush(); 721} 722 723/// resync - This is called when the SmallVector we're appending to is changed 724/// outside of the raw_svector_ostream's control. It is only safe to do this 725/// if the raw_svector_ostream has previously been flushed. 726void raw_svector_ostream::resync() { 727 assert(GetNumBytesInBuffer() == 0 && "Didn't flush before mutating vector"); 728 729 if (OS.capacity() - OS.size() < 64) 730 OS.reserve(OS.capacity() * 2); 731 SetBuffer(OS.end(), OS.capacity() - OS.size()); 732} 733 734void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) { 735 // If we're writing bytes from the end of the buffer into the smallvector, we 736 // don't need to copy the bytes, just commit the bytes because they are 737 // already in the right place. 738 if (Ptr == OS.end()) { 739 assert(OS.size() + Size <= OS.capacity() && "Invalid write_impl() call!"); 740 OS.set_size(OS.size() + Size); 741 } else { 742 assert(GetNumBytesInBuffer() == 0 && 743 "Should be writing from buffer if some bytes in it"); 744 // Otherwise, do copy the bytes. 745 OS.append(Ptr, Ptr+Size); 746 } 747 748 // Grow the vector if necessary. 749 if (OS.capacity() - OS.size() < 64) 750 OS.reserve(OS.capacity() * 2); 751 752 // Update the buffer position. 753 SetBuffer(OS.end(), OS.capacity() - OS.size()); 754} 755 756uint64_t raw_svector_ostream::current_pos() const { 757 return OS.size(); 758} 759 760StringRef raw_svector_ostream::str() { 761 flush(); 762 return StringRef(OS.begin(), OS.size()); 763} 764 765//===----------------------------------------------------------------------===// 766// raw_null_ostream 767//===----------------------------------------------------------------------===// 768 769raw_null_ostream::~raw_null_ostream() { 770#ifndef NDEBUG 771 // ~raw_ostream asserts that the buffer is empty. This isn't necessary 772 // with raw_null_ostream, but it's better to have raw_null_ostream follow 773 // the rules than to change the rules just for raw_null_ostream. 774 flush(); 775#endif 776} 777 778void raw_null_ostream::write_impl(const char *Ptr, size_t Size) { 779} 780 781uint64_t raw_null_ostream::current_pos() const { 782 return 0; 783} 784