StorageFactory/interface/File.h

0001 #ifndef STORAGE_FACTORY_FILE_H
0002 #define STORAGE_FACTORY_FILE_H
0003
0004 #include "Utilities/StorageFactory/interface/IOTypes.h"
0005 #include "Utilities/StorageFactory/interface/IOFlags.h"
0006 #include "Utilities/StorageFactory/interface/Storage.h"
0007 #include <string>
0008
0009 namespace edm::storage {
0010
0011   /** Basic file-related functions.  Nicked from SEAL.  */
0012   class File : public Storage {
0013   public:
0014     File();
0015     File(IOFD fd, bool autoclose = true);
0016     File(const char *name, int flags = IOFlags::OpenRead, int perms = 0666);
0017     File(const std::string &name, int flags = IOFlags::OpenRead, int perms = 0666);
0018     ~File() override;
0019     // implicit copy constructor
0020     // implicit assignment operator
0021
0022     virtual void create(const char *name, bool exclusive = false, int perms = 0666);
0023     virtual void create(const std::string &name, bool exclusive = false, int perms = 0666);
0024     virtual void open(const char *name, int flags = IOFlags::OpenRead, int perms = 0666);
0025     virtual void open(const std::string &name, int flags = IOFlags::OpenRead, int perms = 0666);
0026     virtual void attach(IOFD fd);
0027
0028     using Storage::position;
0029     using Storage::read;
0030     using Storage::readv;
0031     using Storage::write;
0032     using Storage::writev;
0033
0034     IOFD fd() const { return m_fd; }
0035
0036     bool prefetch(const IOPosBuffer *what, IOSize n) override;
0037     IOSize read(void *into, IOSize n) override;
0038     IOSize read(void *into, IOSize n, IOOffset pos) override;
0039     IOSize readv(IOBuffer *into, IOSize length) override;
0040
0041     IOSize write(const void *from, IOSize n) override;
0042     IOSize write(const void *from, IOSize n, IOOffset pos) override;
0043     IOSize writev(const IOBuffer *from, IOSize length) override;
0044
0045     IOOffset size() const override;
0046     IOOffset position(IOOffset offset, Relative whence = SET) override;
0047
0048     void resize(IOOffset size) override;
0049
0050     void flush() override;
0051     void close() override;
0052     virtual void abort();
0053
0054     virtual void setAutoClose(bool closeit);
0055
0056   private:
0057     enum { InternalAutoClose = 4096 };  //< Close on delete
0058
0059     File(IOFD fd, unsigned flags);
0060
0061     IOSize syswrite(const void *from, IOSize n);
0062     IOSize syswritev(const IOBuffer *from, IOSize length);
0063
0064     File *duplicate(bool copy) const;
0065     File *duplicate(File *child) const;
0066     static IOFD sysduplicate(IOFD fd);
0067     static void sysopen(const char *name, int flags, int perms, IOFD &newfd, unsigned &newflags);
0068     static bool sysclose(IOFD fd, int *error = nullptr);
0069
0070     IOFD m_fd = EDM_IOFD_INVALID; /*< System file descriptor. */
0071     unsigned m_flags;
0072   };
0073 }  // namespace edm::storage
0074 #endif  // STORAGE_FACTORY_FILE_H