src/llvm/lib/Support/Unix/Process.inc

   1 //===- Unix/Process.cpp - Unix Process Implementation --------- -*- C++ -*-===//
   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 file provides the generic Unix implementation of the Process class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "Unix.h"
  15 #include "llvm/ADT/Hashing.h"
  16 #include "llvm/ADT/StringRef.h"
  17 #include "llvm/Support/ManagedStatic.h"
  18 #include "llvm/Support/Mutex.h"
  19 #include "llvm/Support/MutexGuard.h"
  20 #include "llvm/Support/TimeValue.h"
  21 #if HAVE_FCNTL_H
  22 #include <fcntl.h>
  23 #endif
  24 #ifdef HAVE_SYS_TIME_H
  25 #include <sys/time.h>
  26 #endif
  27 #ifdef HAVE_SYS_RESOURCE_H
  28 #include <sys/resource.h>
  29 #endif
  30 #ifdef HAVE_SYS_STAT_H
  31 #include <sys/stat.h>
  32 #endif
  33 #if HAVE_SIGNAL_H
  34 #include <signal.h>
  35 #endif
  36 // DragonFlyBSD, OpenBSD, and Bitrig have deprecated <malloc.h> for
  37 // <stdlib.h> instead. Unix.h includes this for us already.
  38 #if defined(HAVE_MALLOC_H) && !defined(__DragonFly__) && \
  39     !defined(__OpenBSD__) && !defined(__Bitrig__)
  40 #include <malloc.h>
  41 #endif
  42 #ifdef HAVE_MALLOC_MALLOC_H
  43 #include <malloc/malloc.h>
  44 #endif
  45 #ifdef HAVE_SYS_IOCTL_H
  46 #  include <sys/ioctl.h>
  47 #endif
  48 #ifdef HAVE_TERMIOS_H
  49 #  include <termios.h>
  50 #endif
  51
  52 //===----------------------------------------------------------------------===//
  53 //=== WARNING: Implementation here must contain only generic UNIX code that
  54 //===          is guaranteed to work on *all* UNIX variants.
  55 //===----------------------------------------------------------------------===//
  56
  57 using namespace llvm;
  58 using namespace sys;
  59
  60 static std::pair<TimeValue, TimeValue> getRUsageTimes() {
  61 #if defined(HAVE_GETRUSAGE)
  62   struct rusage RU;
  63   ::getrusage(RUSAGE_SELF, &RU);
  64   return std::make_pair(
  65       TimeValue(
  66           static_cast<TimeValue::SecondsType>(RU.ru_utime.tv_sec),
  67           static_cast<TimeValue::NanoSecondsType>(
  68               RU.ru_utime.tv_usec * TimeValue::NANOSECONDS_PER_MICROSECOND)),
  69       TimeValue(
  70           static_cast<TimeValue::SecondsType>(RU.ru_stime.tv_sec),
  71           static_cast<TimeValue::NanoSecondsType>(
  72               RU.ru_stime.tv_usec * TimeValue::NANOSECONDS_PER_MICROSECOND)));
  73 #else
  74 #warning Cannot get usage times on this platform
  75   return std::make_pair(TimeValue(), TimeValue());
  76 #endif
  77 }
  78
  79 // On Cygwin, getpagesize() returns 64k(AllocationGranularity) and
  80 // offset in mmap(3) should be aligned to the AllocationGranularity.
  81 unsigned Process::getPageSize() {
  82 #if defined(HAVE_GETPAGESIZE)
  83   static const int page_size = ::getpagesize();
  84 #elif defined(HAVE_SYSCONF)
  85   static long page_size = ::sysconf(_SC_PAGE_SIZE);
  86 #else
  87 #warning Cannot get the page size on this machine
  88 #endif
  89   return static_cast<unsigned>(page_size);
  90 }
  91
  92 size_t Process::GetMallocUsage() {
  93 #if defined(HAVE_MALLINFO)
  94   struct mallinfo mi;
  95   mi = ::mallinfo();
  96   return mi.uordblks;
  97 #elif defined(HAVE_MALLOC_ZONE_STATISTICS) && defined(HAVE_MALLOC_MALLOC_H)
  98   malloc_statistics_t Stats;
  99   malloc_zone_statistics(malloc_default_zone(), &Stats);
 100   return Stats.size_in_use;   // darwin
 101 #elif defined(HAVE_SBRK)
 102   // Note this is only an approximation and more closely resembles
 103   // the value returned by mallinfo in the arena field.
 104   static char *StartOfMemory = reinterpret_cast<char*>(::sbrk(0));
 105   char *EndOfMemory = (char*)sbrk(0);
 106   if (EndOfMemory != ((char*)-1) && StartOfMemory != ((char*)-1))
 107     return EndOfMemory - StartOfMemory;
 108   else
 109     return 0;
 110 #else
 111 #warning Cannot get malloc info on this platform
 112   return 0;
 113 #endif
 114 }
 115
 116 void Process::GetTimeUsage(TimeValue &elapsed, TimeValue &user_time,
 117                            TimeValue &sys_time) {
 118   elapsed = TimeValue::now();
 119   std::tie(user_time, sys_time) = getRUsageTimes();
 120 }
 121
 122 #if defined(HAVE_MACH_MACH_H) && !defined(__GNU__)
 123 #include <mach/mach.h>
 124 #endif
 125
 126 // Some LLVM programs such as bugpoint produce core files as a normal part of
 127 // their operation. To prevent the disk from filling up, this function
 128 // does what's necessary to prevent their generation.
 129 void Process::PreventCoreFiles() {
 130 #if HAVE_SETRLIMIT
 131   struct rlimit rlim;
 132   rlim.rlim_cur = rlim.rlim_max = 0;
 133   setrlimit(RLIMIT_CORE, &rlim);
 134 #endif
 135
 136 #if defined(HAVE_MACH_MACH_H) && !defined(__GNU__)
 137   // Disable crash reporting on Mac OS X 10.0-10.4
 138
 139   // get information about the original set of exception ports for the task
 140   mach_msg_type_number_t Count = 0;
 141   exception_mask_t OriginalMasks[EXC_TYPES_COUNT];
 142   exception_port_t OriginalPorts[EXC_TYPES_COUNT];
 143   exception_behavior_t OriginalBehaviors[EXC_TYPES_COUNT];
 144   thread_state_flavor_t OriginalFlavors[EXC_TYPES_COUNT];
 145   kern_return_t err =
 146     task_get_exception_ports(mach_task_self(), EXC_MASK_ALL, OriginalMasks,
 147                              &Count, OriginalPorts, OriginalBehaviors,
 148                              OriginalFlavors);
 149   if (err == KERN_SUCCESS) {
 150     // replace each with MACH_PORT_NULL.
 151     for (unsigned i = 0; i != Count; ++i)
 152       task_set_exception_ports(mach_task_self(), OriginalMasks[i],
 153                                MACH_PORT_NULL, OriginalBehaviors[i],
 154                                OriginalFlavors[i]);
 155   }
 156
 157   // Disable crash reporting on Mac OS X 10.5
 158   signal(SIGABRT, _exit);
 159   signal(SIGILL,  _exit);
 160   signal(SIGFPE,  _exit);
 161   signal(SIGSEGV, _exit);
 162   signal(SIGBUS,  _exit);
 163 #endif
 164 }
 165
 166 Optional<std::string> Process::GetEnv(StringRef Name) {
 167   std::string NameStr = Name.str();
 168   const char *Val = ::getenv(NameStr.c_str());
 169   if (!Val)
 170     return None;
 171   return std::string(Val);
 172 }
 173
 174 std::error_code
 175 Process::GetArgumentVector(SmallVectorImpl<const char *> &ArgsOut,
 176                            ArrayRef<const char *> ArgsIn,
 177                            SpecificBumpPtrAllocator<char> &) {
 178   ArgsOut.append(ArgsIn.begin(), ArgsIn.end());
 179
 180   return std::error_code();
 181 }
 182
 183 namespace {
 184 class FDCloser {
 185 public:
 186   FDCloser(int &FD) : FD(FD), KeepOpen(false) {}
 187   void keepOpen() { KeepOpen = true; }
 188   ~FDCloser() {
 189     if (!KeepOpen && FD >= 0)
 190       ::close(FD);
 191   }
 192
 193 private:
 194   FDCloser(const FDCloser &) LLVM_DELETED_FUNCTION;
 195   void operator=(const FDCloser &) LLVM_DELETED_FUNCTION;
 196
 197   int &FD;
 198   bool KeepOpen;
 199 };
 200 }
 201
 202 std::error_code Process::FixupStandardFileDescriptors() {
 203   int NullFD = -1;
 204   FDCloser FDC(NullFD);
 205   const int StandardFDs[] = {STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO};
 206   for (int StandardFD : StandardFDs) {
 207     struct stat st;
 208     errno = 0;
 209     while (fstat(StandardFD, &st) < 0) {
 210       assert(errno && "expected errno to be set if fstat failed!");
 211       // fstat should return EBADF if the file descriptor is closed.
 212       if (errno == EBADF)
 213         break;
 214       // retry fstat if we got EINTR, otherwise bubble up the failure.
 215       if (errno != EINTR)
 216         return std::error_code(errno, std::generic_category());
 217     }
 218     // if fstat succeeds, move on to the next FD.
 219     if (!errno)
 220       continue;
 221     assert(errno == EBADF && "expected errno to have EBADF at this point!");
 222
 223     if (NullFD < 0) {
 224       while ((NullFD = open("/dev/null", O_RDWR)) < 0) {
 225         if (errno == EINTR)
 226           continue;
 227         return std::error_code(errno, std::generic_category());
 228       }
 229     }
 230
 231     if (NullFD == StandardFD)
 232       FDC.keepOpen();
 233     else if (dup2(NullFD, StandardFD) < 0)
 234       return std::error_code(errno, std::generic_category());
 235   }
 236   return std::error_code();
 237 }
 238
 239 std::error_code Process::SafelyCloseFileDescriptor(int FD) {
 240   // Create a signal set filled with *all* signals.
 241   sigset_t FullSet;
 242   if (sigfillset(&FullSet) < 0)
 243     return std::error_code(errno, std::generic_category());
 244   // Atomically swap our current signal mask with a full mask.
 245   sigset_t SavedSet;
 246 #if LLVM_ENABLE_THREADS
 247   if (int EC = pthread_sigmask(SIG_SETMASK, &FullSet, &SavedSet))
 248     return std::error_code(EC, std::generic_category());
 249 #else
 250   if (sigprocmask(SIG_SETMASK, &FullSet, &SavedSet) < 0)
 251     return std::error_code(errno, std::generic_category());
 252 #endif
 253   // Attempt to close the file descriptor.
 254   // We need to save the error, if one occurs, because our subsequent call to
 255   // pthread_sigmask might tamper with errno.
 256   int ErrnoFromClose = 0;
 257   if (::close(FD) < 0)
 258     ErrnoFromClose = errno;
 259   // Restore the signal mask back to what we saved earlier.
 260   int EC = 0;
 261 #if LLVM_ENABLE_THREADS
 262   EC = pthread_sigmask(SIG_SETMASK, &SavedSet, nullptr);
 263 #else
 264   if (sigprocmask(SIG_SETMASK, &SavedSet, nullptr) < 0)
 265     EC = errno;
 266 #endif
 267   // The error code from close takes precedence over the one from
 268   // pthread_sigmask.
 269   if (ErrnoFromClose)
 270     return std::error_code(ErrnoFromClose, std::generic_category());
 271   return std::error_code(EC, std::generic_category());
 272 }
 273
 274 bool Process::StandardInIsUserInput() {
 275   return FileDescriptorIsDisplayed(STDIN_FILENO);
 276 }
 277
 278 bool Process::StandardOutIsDisplayed() {
 279   return FileDescriptorIsDisplayed(STDOUT_FILENO);
 280 }
 281
 282 bool Process::StandardErrIsDisplayed() {
 283   return FileDescriptorIsDisplayed(STDERR_FILENO);
 284 }
 285
 286 bool Process::FileDescriptorIsDisplayed(int fd) {
 287 #if HAVE_ISATTY
 288   return isatty(fd);
 289 #else
 290   // If we don't have isatty, just return false.
 291   return false;
 292 #endif
 293 }
 294
 295 static unsigned getColumns(int FileID) {
 296   // If COLUMNS is defined in the environment, wrap to that many columns.
 297   if (const char *ColumnsStr = std::getenv("COLUMNS")) {
 298     int Columns = std::atoi(ColumnsStr);
 299     if (Columns > 0)
 300       return Columns;
 301   }
 302
 303   unsigned Columns = 0;
 304
 305 #if defined(HAVE_SYS_IOCTL_H) && defined(HAVE_TERMIOS_H)
 306   // Try to determine the width of the terminal.
 307   struct winsize ws;
 308   if (ioctl(FileID, TIOCGWINSZ, &ws) == 0)
 309     Columns = ws.ws_col;
 310 #endif
 311
 312   return Columns;
 313 }
 314
 315 unsigned Process::StandardOutColumns() {
 316   if (!StandardOutIsDisplayed())
 317     return 0;
 318
 319   return getColumns(1);
 320 }
 321
 322 unsigned Process::StandardErrColumns() {
 323   if (!StandardErrIsDisplayed())
 324     return 0;
 325
 326   return getColumns(2);
 327 }
 328
 329 #ifdef HAVE_TERMINFO
 330 // We manually declare these extern functions because finding the correct
 331 // headers from various terminfo, curses, or other sources is harder than
 332 // writing their specs down.
 333 extern "C" int setupterm(char *term, int filedes, int *errret);
 334 extern "C" struct term *set_curterm(struct term *termp);
 335 extern "C" int del_curterm(struct term *termp);
 336 extern "C" int tigetnum(char *capname);
 337 #endif
 338
 339 #ifdef HAVE_TERMINFO
 340 static ManagedStatic<sys::Mutex> TermColorMutex;
 341 #endif
 342
 343 static bool terminalHasColors(int fd) {
 344 #ifdef HAVE_TERMINFO
 345   // First, acquire a global lock because these C routines are thread hostile.
 346   MutexGuard G(*TermColorMutex);
 347
 348   int errret = 0;
 349   if (setupterm((char *)nullptr, fd, &errret) != 0)
 350     // Regardless of why, if we can't get terminfo, we shouldn't try to print
 351     // colors.
 352     return false;
 353
 354   // Test whether the terminal as set up supports color output. How to do this
 355   // isn't entirely obvious. We can use the curses routine 'has_colors' but it
 356   // would be nice to avoid a dependency on curses proper when we can make do
 357   // with a minimal terminfo parsing library. Also, we don't really care whether
 358   // the terminal supports the curses-specific color changing routines, merely
 359   // if it will interpret ANSI color escape codes in a reasonable way. Thus, the
 360   // strategy here is just to query the baseline colors capability and if it
 361   // supports colors at all to assume it will translate the escape codes into
 362   // whatever range of colors it does support. We can add more detailed tests
 363   // here if users report them as necessary.
 364   //
 365   // The 'tigetnum' routine returns -2 or -1 on errors, and might return 0 if
 366   // the terminfo says that no colors are supported.
 367   bool HasColors = tigetnum(const_cast<char *>("colors")) > 0;
 368
 369   // Now extract the structure allocated by setupterm and free its memory
 370   // through a really silly dance.
 371   struct term *termp = set_curterm((struct term *)nullptr);
 372   (void)del_curterm(termp); // Drop any errors here.
 373
 374   // Return true if we found a color capabilities for the current terminal.
 375   if (HasColors)
 376     return true;
 377 #endif
 378
 379   // Otherwise, be conservative.
 380   return false;
 381 }
 382
 383 bool Process::FileDescriptorHasColors(int fd) {
 384   // A file descriptor has colors if it is displayed and the terminal has
 385   // colors.
 386   return FileDescriptorIsDisplayed(fd) && terminalHasColors(fd);
 387 }
 388
 389 bool Process::StandardOutHasColors() {
 390   return FileDescriptorHasColors(STDOUT_FILENO);
 391 }
 392
 393 bool Process::StandardErrHasColors() {
 394   return FileDescriptorHasColors(STDERR_FILENO);
 395 }
 396
 397 void Process::UseANSIEscapeCodes(bool /*enable*/) {
 398   // No effect.
 399 }
 400
 401 bool Process::ColorNeedsFlush() {
 402   // No, we use ANSI escape sequences.
 403   return false;
 404 }
 405
 406 const char *Process::OutputColor(char code, bool bold, bool bg) {
 407   return colorcodes[bg?1:0][bold?1:0][code&7];
 408 }
 409
 410 const char *Process::OutputBold(bool bg) {
 411   return "\033[1m";
 412 }
 413
 414 const char *Process::OutputReverse() {
 415   return "\033[7m";
 416 }
 417
 418 const char *Process::ResetColor() {
 419   return "\033[0m";
 420 }
 421
 422 #if !defined(HAVE_DECL_ARC4RANDOM) || !HAVE_DECL_ARC4RANDOM
 423 static unsigned GetRandomNumberSeed() {
 424   // Attempt to get the initial seed from /dev/urandom, if possible.
 425   if (FILE *RandomSource = ::fopen("/dev/urandom", "r")) {
 426     unsigned seed;
 427     int count = ::fread((void *)&seed, sizeof(seed), 1, RandomSource);
 428     ::fclose(RandomSource);
 429
 430     // Return the seed if the read was successful.
 431     if (count == 1)
 432       return seed;
 433   }
 434
 435   // Otherwise, swizzle the current time and the process ID to form a reasonable
 436   // seed.
 437   TimeValue Now = TimeValue::now();
 438   return hash_combine(Now.seconds(), Now.nanoseconds(), ::getpid());
 439 }
 440 #endif
 441
 442 unsigned llvm::sys::Process::GetRandomNumber() {
 443 #if defined(HAVE_DECL_ARC4RANDOM) && HAVE_DECL_ARC4RANDOM
 444   return arc4random();
 445 #else
 446   static int x = (::srand(GetRandomNumberSeed()), 0);
 447   (void)x;
 448   return ::rand();
 449 #endif
 450 }