lib/Support/raw_ostream.cpp

   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/System/Program.h"
  17 #include "llvm/System/Process.h"
  18 #include "llvm/ADT/SmallVector.h"
  19 #include "llvm/Config/config.h"
  20 #include "llvm/Support/Compiler.h"
  21 #include "llvm/Support/ErrorHandling.h"
  22 #include <ostream>
  23
  24 #if defined(HAVE_UNISTD_H)
  25 # include <unistd.h>
  26 #endif
  27 #if defined(HAVE_FCNTL_H)
  28 # include <fcntl.h>
  29 #endif
  30
  31 #if defined(_MSC_VER)
  32 #include <io.h>
  33 #include <fcntl.h>
  34 #ifndef STDIN_FILENO
  35 # define STDIN_FILENO 0
  36 #endif
  37 #ifndef STDOUT_FILENO
  38 # define STDOUT_FILENO 1
  39 #endif
  40 #ifndef STDERR_FILENO
  41 # define STDERR_FILENO 2
  42 #endif
  43 #endif
  44
  45 using namespace llvm;
  46
  47 raw_ostream::~raw_ostream() {
  48   delete [] OutBufStart;
  49
  50   // If there are any pending errors, report them now. Clients wishing
  51   // to avoid llvm_report_error calls should check for errors with
  52   // has_error() and clear the error flag with clear_error() before
  53   // destructing raw_ostream objects which may have errors.
  54   if (Error)
  55     llvm_report_error("IO failure on output stream.");
  56 }
  57
  58 // An out of line virtual method to provide a home for the class vtable.
  59 void raw_ostream::handle() {}
  60
  61 raw_ostream &raw_ostream::operator<<(unsigned long N) {
  62   // Zero is a special case.
  63   if (N == 0)
  64     return *this << '0';
  65
  66   char NumberBuffer[20];
  67   char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
  68   char *CurPtr = EndPtr;
  69
  70   while (N) {
  71     *--CurPtr = '0' + char(N % 10);
  72     N /= 10;
  73   }
  74   return write(CurPtr, EndPtr-CurPtr);
  75 }
  76
  77 raw_ostream &raw_ostream::operator<<(long N) {
  78   if (N <  0) {
  79     *this << '-';
  80     N = -N;
  81   }
  82
  83   return this->operator<<(static_cast<unsigned long>(N));
  84 }
  85
  86 raw_ostream &raw_ostream::operator<<(unsigned long long N) {
  87   // Zero is a special case.
  88   if (N == 0)
  89     return *this << '0';
  90
  91   char NumberBuffer[20];
  92   char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
  93   char *CurPtr = EndPtr;
  94
  95   while (N) {
  96     *--CurPtr = '0' + char(N % 10);
  97     N /= 10;
  98   }
  99   return write(CurPtr, EndPtr-CurPtr);
 100 }
 101
 102 raw_ostream &raw_ostream::operator<<(long long N) {
 103   if (N <  0) {
 104     *this << '-';
 105     N = -N;
 106   }
 107
 108   return this->operator<<(static_cast<unsigned long long>(N));
 109 }
 110
 111 raw_ostream &raw_ostream::operator<<(const void *P) {
 112   uintptr_t N = (uintptr_t) P;
 113   *this << '0' << 'x';
 114
 115   // Zero is a special case.
 116   if (N == 0)
 117     return *this << '0';
 118
 119   char NumberBuffer[20];
 120   char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
 121   char *CurPtr = EndPtr;
 122
 123   while (N) {
 124     unsigned x = N % 16;
 125     *--CurPtr = (x < 10 ? '0' + x : 'a' + x - 10);
 126     N /= 16;
 127   }
 128
 129   return write(CurPtr, EndPtr-CurPtr);
 130 }
 131
 132 void raw_ostream::flush_nonempty() {
 133   assert(OutBufCur > OutBufStart && "Invalid call to flush_nonempty.");
 134   write_impl(OutBufStart, OutBufCur - OutBufStart);
 135   OutBufCur = OutBufStart;
 136 }
 137
 138 raw_ostream &raw_ostream::write(unsigned char C) {
 139   // Group exceptional cases into a single branch.
 140   if (OutBufCur >= OutBufEnd) {
 141     if (Unbuffered) {
 142       write_impl(reinterpret_cast<char*>(&C), 1);
 143       return *this;
 144     }
 145
 146     if (!OutBufStart)
 147       SetBufferSize();
 148     else
 149       flush_nonempty();
 150   }
 151
 152   *OutBufCur++ = C;
 153   return *this;
 154 }
 155
 156 raw_ostream &raw_ostream::write(const char *Ptr, unsigned Size) {
 157   // Group exceptional cases into a single branch.
 158   if (BUILTIN_EXPECT(OutBufCur+Size > OutBufEnd, false)) {
 159     if (Unbuffered) {
 160       write_impl(Ptr, Size);
 161       return *this;
 162     }
 163
 164     if (!OutBufStart)
 165       SetBufferSize();
 166     else
 167       flush_nonempty();
 168   }
 169
 170   // Handle short strings specially, memcpy isn't very good at very short
 171   // strings.
 172   switch (Size) {
 173   case 4: OutBufCur[3] = Ptr[3]; // FALL THROUGH
 174   case 3: OutBufCur[2] = Ptr[2]; // FALL THROUGH
 175   case 2: OutBufCur[1] = Ptr[1]; // FALL THROUGH
 176   case 1: OutBufCur[0] = Ptr[0]; // FALL THROUGH
 177   case 0: break;
 178   default:
 179     // Normally the string to emit is shorter than the buffer.
 180     if (Size <= unsigned(OutBufEnd-OutBufCur)) {
 181       memcpy(OutBufCur, Ptr, Size);
 182       break;
 183     }
 184
 185     // Otherwise we are emitting a string larger than our buffer. We
 186     // know we already flushed, so just write it out directly.
 187     write_impl(Ptr, Size);
 188     Size = 0;
 189     break;
 190   }
 191   OutBufCur += Size;
 192
 193   return *this;
 194 }
 195
 196 // Formatted output.
 197 raw_ostream &raw_ostream::operator<<(const format_object_base &Fmt) {
 198   // If we have more than a few bytes left in our output buffer, try
 199   // formatting directly onto its end.
 200   //
 201   // FIXME: This test is a bit silly, since if we don't have enough
 202   // space in the buffer we will have to flush the formatted output
 203   // anyway. We should just flush upfront in such cases, and use the
 204   // whole buffer as our scratch pad. Note, however, that this case is
 205   // also necessary for correctness on unbuffered streams.
 206   unsigned NextBufferSize = 127;
 207   if (OutBufEnd-OutBufCur > 3) {
 208     unsigned BufferBytesLeft = OutBufEnd-OutBufCur;
 209     unsigned BytesUsed = Fmt.print(OutBufCur, BufferBytesLeft);
 210
 211     // Common case is that we have plenty of space.
 212     if (BytesUsed < BufferBytesLeft) {
 213       OutBufCur += BytesUsed;
 214       return *this;
 215     }
 216
 217     // Otherwise, we overflowed and the return value tells us the size to try
 218     // again with.
 219     NextBufferSize = BytesUsed;
 220   }
 221
 222   // If we got here, we didn't have enough space in the output buffer for the
 223   // string.  Try printing into a SmallVector that is resized to have enough
 224   // space.  Iterate until we win.
 225   SmallVector<char, 128> V;
 226
 227   while (1) {
 228     V.resize(NextBufferSize);
 229
 230     // Try formatting into the SmallVector.
 231     unsigned BytesUsed = Fmt.print(&V[0], NextBufferSize);
 232
 233     // If BytesUsed fit into the vector, we win.
 234     if (BytesUsed <= NextBufferSize)
 235       return write(&V[0], BytesUsed);
 236
 237     // Otherwise, try again with a new size.
 238     assert(BytesUsed > NextBufferSize && "Didn't grow buffer!?");
 239     NextBufferSize = BytesUsed;
 240   }
 241 }
 242
 243 //===----------------------------------------------------------------------===//
 244 //  Formatted Output
 245 //===----------------------------------------------------------------------===//
 246
 247 // Out of line virtual method.
 248 void format_object_base::home() {
 249 }
 250
 251 //===----------------------------------------------------------------------===//
 252 //  raw_fd_ostream
 253 //===----------------------------------------------------------------------===//
 254
 255 /// raw_fd_ostream - Open the specified file for writing. If an error
 256 /// occurs, information about the error is put into ErrorInfo, and the
 257 /// stream should be immediately destroyed; the string will be empty
 258 /// if no error occurred.
 259 raw_fd_ostream::raw_fd_ostream(const char *Filename, bool Binary, bool Force,
 260                                std::string &ErrorInfo) : pos(0) {
 261   ErrorInfo.clear();
 262
 263   // Handle "-" as stdout.
 264   if (Filename[0] == '-' && Filename[1] == 0) {
 265     FD = STDOUT_FILENO;
 266     // If user requested binary then put stdout into binary mode if
 267     // possible.
 268     if (Binary)
 269       sys::Program::ChangeStdoutToBinary();
 270     ShouldClose = false;
 271     return;
 272   }
 273
 274   int Flags = O_WRONLY|O_CREAT|O_TRUNC;
 275 #ifdef O_BINARY
 276   if (Binary)
 277     Flags |= O_BINARY;
 278 #endif
 279   if (!Force)
 280     Flags |= O_EXCL;
 281   FD = open(Filename, Flags, 0664);
 282   if (FD < 0) {
 283     ErrorInfo = "Error opening output file '" + std::string(Filename) + "'";
 284     ShouldClose = false;
 285   } else {
 286     ShouldClose = true;
 287   }
 288 }
 289
 290 raw_fd_ostream::~raw_fd_ostream() {
 291   if (FD >= 0) {
 292     flush();
 293     if (ShouldClose)
 294       if (::close(FD) != 0)
 295         error_detected();
 296   }
 297 }
 298
 299 void raw_fd_ostream::write_impl(const char *Ptr, unsigned Size) {
 300   assert (FD >= 0 && "File already closed.");
 301   pos += Size;
 302   if (::write(FD, Ptr, Size) != (ssize_t) Size)
 303     error_detected();
 304 }
 305
 306 void raw_fd_ostream::close() {
 307   assert (ShouldClose);
 308   ShouldClose = false;
 309   flush();
 310   if (::close(FD) != 0)
 311     error_detected();
 312   FD = -1;
 313 }
 314
 315 uint64_t raw_fd_ostream::seek(uint64_t off) {
 316   flush();
 317   pos = ::lseek(FD, off, SEEK_SET);
 318   if (pos != off)
 319     error_detected();
 320   return pos;
 321 }
 322
 323 raw_ostream &raw_fd_ostream::changeColor(enum Colors colors, bool bold,
 324                                          bool bg) {
 325   if (sys::Process::ColorNeedsFlush())
 326     flush();
 327   const char *colorcode =
 328     (colors == SAVEDCOLOR) ? sys::Process::OutputBold(bg)
 329     : sys::Process::OutputColor(colors, bold, bg);
 330   if (colorcode) {
 331     unsigned len = strlen(colorcode);
 332     write(colorcode, len);
 333     // don't account colors towards output characters
 334     pos -= len;
 335   }
 336   return *this;
 337 }
 338
 339 raw_ostream &raw_fd_ostream::resetColor() {
 340   if (sys::Process::ColorNeedsFlush())
 341     flush();
 342   const char *colorcode = sys::Process::ResetColor();
 343   if (colorcode) {
 344     unsigned len = strlen(colorcode);
 345     write(colorcode, len);
 346     // don't account colors towards output characters
 347     pos -= len;
 348   }
 349   return *this;
 350 }
 351
 352 //===----------------------------------------------------------------------===//
 353 //  raw_stdout/err_ostream
 354 //===----------------------------------------------------------------------===//
 355
 356 raw_stdout_ostream::raw_stdout_ostream():raw_fd_ostream(STDOUT_FILENO, false) {}
 357 raw_stderr_ostream::raw_stderr_ostream():raw_fd_ostream(STDERR_FILENO, false,
 358                                                         true) {}
 359
 360 // An out of line virtual method to provide a home for the class vtable.
 361 void raw_stdout_ostream::handle() {}
 362 void raw_stderr_ostream::handle() {}
 363
 364 /// outs() - This returns a reference to a raw_ostream for standard output.
 365 /// Use it like: outs() << "foo" << "bar";
 366 raw_ostream &llvm::outs() {
 367   static raw_stdout_ostream S;
 368   return S;
 369 }
 370
 371 /// errs() - This returns a reference to a raw_ostream for standard error.
 372 /// Use it like: errs() << "foo" << "bar";
 373 raw_ostream &llvm::errs() {
 374   static raw_stderr_ostream S;
 375   return S;
 376 }
 377
 378 //===----------------------------------------------------------------------===//
 379 //  raw_os_ostream
 380 //===----------------------------------------------------------------------===//
 381
 382 raw_os_ostream::~raw_os_ostream() {
 383   flush();
 384 }
 385
 386 void raw_os_ostream::write_impl(const char *Ptr, unsigned Size) {
 387   OS.write(Ptr, Size);
 388 }
 389
 390 uint64_t raw_os_ostream::current_pos() { return OS.tellp(); }
 391
 392 uint64_t raw_os_ostream::tell() {
 393   return (uint64_t)OS.tellp() + GetNumBytesInBuffer();
 394 }
 395
 396 //===----------------------------------------------------------------------===//
 397 //  raw_string_ostream
 398 //===----------------------------------------------------------------------===//
 399
 400 raw_string_ostream::~raw_string_ostream() {
 401   flush();
 402 }
 403
 404 void raw_string_ostream::write_impl(const char *Ptr, unsigned Size) {
 405   OS.append(Ptr, Size);
 406 }
 407
 408 //===----------------------------------------------------------------------===//
 409 //  raw_svector_ostream
 410 //===----------------------------------------------------------------------===//
 411
 412 raw_svector_ostream::~raw_svector_ostream() {
 413   flush();
 414 }
 415
 416 void raw_svector_ostream::write_impl(const char *Ptr, unsigned Size) {
 417   OS.append(Ptr, Ptr + Size);
 418 }
 419
 420 uint64_t raw_svector_ostream::current_pos() { return OS.size(); }
 421
 422 uint64_t raw_svector_ostream::tell() {
 423   return OS.size() + GetNumBytesInBuffer();
 424 }