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File indexing completed on 2021-10-01 22:41:13

0001 #include "Utilities/StorageFactory/interface/File.h"
0002 #include "Utilities/StorageFactory/src/SysFile.h"
0003 #include "Utilities/StorageFactory/src/Throw.h"
0004 #include "FWCore/Utilities/interface/EDMException.h"
0005 #include <cassert>
0006 #include <vector>
0007 
0008 using namespace edm::storage;
0009 
0010 using namespace IOFlags;
0011 
0012 IOFD File::sysduplicate(IOFD fd) {
0013   IOFD copyfd;
0014   if ((copyfd = ::dup(fd)) == EDM_IOFD_INVALID)
0015     throwStorageError("FileDuplicateError", "Calling File::sysduplicate()", "dup()", errno);
0016 
0017   return copyfd;
0018 }
0019 
0020 void File::sysopen(const char *name, int flags, int perms, IOFD &newfd, unsigned int & /*newflags*/) {
0021   // Translate our flags to system flags.
0022   int openflags = 0;
0023 
0024   if ((flags & OpenRead) && (flags & OpenWrite))
0025     openflags |= O_RDWR;
0026   else if (flags & OpenRead)
0027     openflags |= O_RDONLY;
0028   else if (flags & OpenWrite)
0029     openflags |= O_WRONLY;
0030 
0031   if (flags & OpenNonBlock)
0032     openflags |= O_NONBLOCK;
0033 
0034   if (flags & OpenAppend)
0035     openflags |= O_APPEND;
0036 
0037 #ifdef O_SYNC
0038   if (flags & OpenUnbuffered)
0039     openflags |= O_SYNC;
0040 #else
0041   if (flags & OpenUnbuffered)
0042     newflags |= OpenUnbuffered;
0043 #endif
0044 
0045   if (flags & OpenCreate)
0046     openflags |= O_CREAT;
0047 
0048   if (flags & OpenExclusive)
0049     openflags |= O_EXCL;
0050 
0051   if (flags & OpenTruncate)
0052     openflags |= O_TRUNC;
0053 
0054   if (flags & OpenNotCTTY)
0055     openflags |= O_NOCTTY;
0056 
0057   if ((newfd = ::open(name, openflags, perms)) == -1)
0058     throwStorageError(edm::errors::FileOpenError, "Calling File::sysopen()", "open()", errno);
0059 }
0060 
0061 IOSize File::read(void *into, IOSize n) {
0062   ssize_t s;
0063   do
0064     s = ::read(fd(), into, n);
0065   while (s == -1 && errno == EINTR);
0066 
0067   if (s == -1)
0068     throwStorageError(edm::errors::FileReadError, "Calling File::read()", "read()", errno);
0069 
0070   return s;
0071 }
0072 
0073 IOSize File::readv(IOBuffer *into, IOSize buffers) {
0074   assert(!buffers || into);
0075 
0076   // readv may not support zero buffers.
0077   if (!buffers)
0078     return 0;
0079 
0080   ssize_t n = 0;
0081 
0082   // Convert the buffers to system format.
0083   std::vector<iovec> bufs(buffers);
0084   for (IOSize i = 0; i < buffers; ++i) {
0085     bufs[i].iov_len = into[i].size();
0086     bufs[i].iov_base = (caddr_t)into[i].data();
0087   }
0088 
0089   // Read as long as signals cancel the read before doing anything.
0090   do
0091     n = ::readv(fd(), &bufs[0], buffers);
0092   while (n == -1 && errno == EINTR);
0093 
0094   // If it was serious error, throw it.
0095   if (n == -1)
0096     throwStorageError(edm::errors::FileReadError, "Calling File::readv", "readv()", errno);
0097 
0098   // Return the number of bytes actually read.
0099   return n;
0100 }
0101 
0102 IOSize File::read(void *into, IOSize n, IOOffset pos) {
0103   assert(pos >= 0);
0104 
0105   ssize_t s;
0106   do
0107     s = ::pread(fd(), into, n, pos);
0108   while (s == -1 && errno == EINTR);
0109 
0110   if (s == -1)
0111     throwStorageError(edm::errors::FileReadError, "Calling File::read()", "pread()", errno);
0112 
0113   return s;
0114 }
0115 
0116 IOSize File::syswrite(const void *from, IOSize n) {
0117   ssize_t s;
0118   do
0119     s = ::write(fd(), from, n);
0120   while (s == -1 && errno == EINTR);
0121 
0122   if (s == -1 && errno != EWOULDBLOCK)
0123     throwStorageError(edm::errors::FileWriteError, "Calling File::syswrite()", "syswrite()", errno);
0124 
0125   return s >= 0 ? s : 0;
0126 }
0127 
0128 IOSize File::syswritev(const IOBuffer *from, IOSize buffers) {
0129   assert(!buffers || from);
0130 
0131   // writev may not support zero buffers.
0132   if (!buffers)
0133     return 0;
0134 
0135   ssize_t n = 0;
0136 
0137   // Convert the buffers to system format.
0138   std::vector<iovec> bufs(buffers);
0139   for (IOSize i = 0; i < buffers; ++i) {
0140     bufs[i].iov_len = from[i].size();
0141     bufs[i].iov_base = (caddr_t)from[i].data();
0142   }
0143 
0144   // Read as long as signals cancel the read before doing anything.
0145   do
0146     n = ::writev(fd(), &bufs[0], buffers);
0147   while (n == -1 && errno == EINTR);
0148 
0149   // If it was serious error, throw it.
0150   if (n == -1)
0151     throwStorageError(edm::errors::FileWriteError, "Calling Fike::syswritev()", "syswritev()", errno);
0152 
0153   // Return the number of bytes actually written.
0154   return n;
0155 }
0156 
0157 IOSize File::write(const void *from, IOSize n, IOOffset pos) {
0158   assert(pos >= 0);
0159 
0160   ssize_t s;
0161   do
0162     s = ::pwrite(fd(), from, n, pos);
0163   while (s == -1 && errno == EINTR);
0164 
0165   if (s == -1)
0166     throwStorageError(edm::errors::FileWriteError, "Calling File::write()", "pwrite()", errno);
0167 
0168   if (m_flags & OpenUnbuffered)
0169     // FIXME: Exception handling?
0170     flush();
0171 
0172   return s;
0173 }
0174 
0175 IOOffset File::size() const {
0176   IOFD fd = m_fd;
0177   assert(fd != EDM_IOFD_INVALID);
0178 
0179   struct stat info;
0180   if (fstat(fd, &info) == -1)
0181     throwStorageError("FileSizeError", "Calling File::size()", "fstat()", errno);
0182 
0183   return info.st_size;
0184 }
0185 
0186 IOOffset File::position(IOOffset offset, Relative whence /* = SET */) {
0187   IOFD fd = m_fd;
0188   assert(fd != EDM_IOFD_INVALID);
0189   assert(whence == CURRENT || whence == SET || whence == END);
0190 
0191   IOOffset result;
0192   int mywhence = (whence == SET ? SEEK_SET : whence == CURRENT ? SEEK_CUR : SEEK_END);
0193   if ((result = ::lseek(fd, offset, mywhence)) == -1)
0194     throwStorageError("FilePositionError", "Calling File::position()", "lseek()", errno);
0195 
0196   return result;
0197 }
0198 
0199 void File::resize(IOOffset size) {
0200   IOFD fd = m_fd;
0201   assert(fd != EDM_IOFD_INVALID);
0202 
0203   if (ftruncate(fd, size) == -1)
0204     throwStorageError("FileResizeError", "Calling File::resize()", "ftruncate()", errno);
0205 }
0206 
0207 void File::flush() {
0208   IOFD fd = m_fd;
0209   assert(fd != EDM_IOFD_INVALID);
0210 
0211 #if _POSIX_SYNCHRONIZED_IO > 0
0212   if (fdatasync(fd) == -1)
0213     throwStorageError("FileFlushError", "Calling File::flush()", "fdatasync()", errno);
0214 #elif _POSIX_FSYNC > 0
0215   if (fsync(fd) == -1)
0216     throwStorageError("FileFlushError", "Calling File::flush()", "fsync()", errno);
0217 #endif
0218 }
0219 
0220 bool File::sysclose(IOFD fd, int *error /* = 0 */) {
0221   int ret = ::close(fd);
0222   if (error)
0223     *error = errno;
0224   return ret != -1;
0225 }