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 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 /*

  * Robin J. Maxwell 11-22-96

  * Fredrik Roubert <roubert@google.com> 2010-07-23

  * Matt Austern <austern@google.com> 2010-07-23

  */

 #include "prstrms.h"

 #include <cstdio>

 #include <cstring>

 #include <ios>

 #include <new>

 using std::ios_base;

 using std::iostream;

 using std::istream;

 using std::nothrow;

 using std::ostream;

 using std::streambuf;

 using std::streamsize;

 PRfilebuf::PRfilebuf():

     _fd(NULL),

     _opened(false),

     _allocated(false),

     _unbuffered(false),

     _user_buf(false),

     _buf_base(NULL),

     _buf_end(NULL) { }

 PRfilebuf::PRfilebuf(PRFileDesc *fd):

     _fd(fd),

     _opened(false),

     _allocated(false),

     _unbuffered(false),

     _user_buf(false),

     _buf_base(NULL),

     _buf_end(NULL) { }

 PRfilebuf::PRfilebuf(PRFileDesc *fd, char_type *ptr, streamsize len):

     _fd(fd),

     _opened(false),

     _allocated(false),

     _unbuffered(false),

     _user_buf(false),

     _buf_base(NULL),

     _buf_end(NULL)

 {

     setbuf(ptr, len);

 }

 PRfilebuf::~PRfilebuf()

 {

     if (_opened) {

         close();

     } else {

         sync();

     }

     if (_allocated) {

         delete _buf_base;

     }

 }

 PRfilebuf *PRfilebuf::open(

     const char *name, ios_base::openmode flags, PRIntn mode)

 {

     if (_fd != NULL) {

         return NULL;  // Error if already open.

     }

     // Translate flags argument.

     PRIntn prflags = 0;

     bool ate = (flags & ios_base::ate) != 0;

     flags &= ~(ios_base::ate | ios_base::binary);

     // TODO: The flag PR_CREATE_FILE should probably be used for the cases

     // (out), (out|app), (out|trunc) and (in|out|trunc) as the C++ standard

     // specifies that these cases should open files 'as if by using fopen with

     // "w"'. But adding that flag here will cause the unit test to leave files

     // behind after running (which might or might not be an error in the unit

     // test) so the matter needs further investigation before any changes are

     // made. The old prstreams implementation used the non-standard flag

     // ios::nocreate to control the use of PR_CREATE_FILE.

     if (flags == (ios_base::out)) {

         prflags = PR_WRONLY | PR_TRUNCATE;

     } else if (flags == (ios_base::out | ios_base::app)) {

         prflags = PR_RDWR | PR_APPEND;

     } else if (flags == (ios_base::out | ios_base::trunc)) {

         prflags = PR_WRONLY | PR_TRUNCATE;

     } else if (flags == (ios_base::in)) {

         prflags = PR_RDONLY;

     } else if (flags == (ios_base::in | ios_base::out)) {

         prflags = PR_RDWR;

     } else if (flags == (ios_base::in | ios_base::out | ios_base::trunc)) {

         prflags = PR_RDWR | PR_TRUNCATE;

     } else {

         return NULL;  // Unrecognized flag combination.

     }

     if ((_fd = PR_Open(name, prflags, mode)) == NULL) {

         return NULL;

     }

     _opened = true;

     if (ate &&

             seekoff(0, ios_base::end, flags) == pos_type(traits_type::eof())) {

         close();

         return NULL;

     }

     return this;

 }

 PRfilebuf *PRfilebuf::attach(PRFileDesc *fd)

 {

     if (_fd != NULL) {

         return NULL;  // Error if already open.

     }

     _opened = false;

     _fd = fd;

     return this;

 }

 PRfilebuf *PRfilebuf::close()

 {

     if (_fd == NULL)

         return NULL;

     int status = sync();

     if (PR_Close(_fd) == PR_FAILURE ||

             traits_type::eq_int_type(status, traits_type::eof())) {

         return NULL;

     }

     _fd = NULL;

     return this;

 }

 streambuf *PRfilebuf::setbuf(char_type *ptr, streamsize len)

 {

     if (is_open() && _buf_end) {

         return NULL;

     }

     if (!ptr || len <= 0) {

         _unbuffered = true;

     } else {

         setb(ptr, ptr + len, false);

     }

     return this;

 }

 streambuf::pos_type PRfilebuf::seekoff(

     off_type offset, ios_base::seekdir dir, ios_base::openmode /*flags*/)

 {

     if (PR_GetDescType(_fd) != PR_DESC_FILE) {

         return traits_type::eof();

     }

     PRSeekWhence whence;

     PRInt64 pos;

     switch (dir) {

         case ios_base::beg: whence = PR_SEEK_SET; break;

         case ios_base::cur: whence = PR_SEEK_CUR; break;

         case ios_base::end: whence = PR_SEEK_END; break;

         default:

             return traits_type::eof();  // This should never happen.

     }

     if (traits_type::eq_int_type(sync(), traits_type::eof())) {

         return traits_type::eof();

     }

     if ((pos = PR_Seek64(_fd, offset, whence)) == -1) {

         return traits_type::eof();

     }

     return pos;

 }

 int PRfilebuf::sync()

 {

     if (_fd == NULL) {

         return traits_type::eof();

     }

     if (!_unbuffered) {

         // Sync write area.

         PRInt32 waiting;

         if ((waiting = pptr() - pbase()) != 0) {

             PRInt32 nout;

             if ((nout = PR_Write(_fd, pbase(), waiting)) != waiting) {

                 if (nout > 0) {

                     // Should set _pptr -= nout.

                     pbump(-nout);

                     memmove(pbase(), pbase() + nout, waiting - nout);

                 }

                 return traits_type::eof();

             }

         }

         setp(NULL, NULL);  // Empty put area.

         if (PR_GetDescType(_fd) == PR_DESC_FILE) {

             // Sockets can't seek; don't need this.

             PROffset64 avail;

             if ((avail = in_avail()) > 0) {

                 if (PR_Seek64(_fd, -avail, PR_SEEK_CUR) != -1) {

                     return traits_type::eof();

                 }

             }

         }

         setg(NULL, NULL, NULL);  // Empty get area.

     }

     return 0;

 }

 streambuf::int_type PRfilebuf::underflow()

 {

     PRInt32 count;

     char_type byte;

     if (gptr() != NULL && gptr() < egptr()) {

         return traits_type::to_int_type(*gptr());

     }

     // Make sure there is a reserve area.

     if (!_unbuffered && _buf_base == NULL && !allocate()) {

         return traits_type::eof();

     }

     // Sync before new buffer created below.

     if (traits_type::eq_int_type(sync(), traits_type::eof())) {

         return traits_type::eof();

     }

     if (_unbuffered) {

         if (PR_Read(_fd, &byte, 1) <= 0) {

             return traits_type::eof();

         }

         return traits_type::to_int_type(byte);

     }

     if ((count = PR_Read(_fd, _buf_base, _buf_end - _buf_base)) <= 0) {

         return traits_type::eof();  // Reached EOF.

     }

     setg(_buf_base, _buf_base, _buf_base + count);

     return traits_type::to_int_type(*gptr());

 }

 streambuf::int_type PRfilebuf::overflow(int_type c)

 {

     // Make sure there is a reserve area.

     if (!_unbuffered && _buf_base == NULL && !allocate()) {

         return traits_type::eof();

     }

     // Sync before new buffer created below.

     if (traits_type::eq_int_type(sync(), traits_type::eof())) {

         return traits_type::eof();

     }

     if (!_unbuffered) {

         setp(_buf_base, _buf_end);

     }

     if (!traits_type::eq_int_type(c, traits_type::eof())) {

         // Extract the byte to be written.

         // (Required on big-endian architectures.)

         char_type byte = traits_type::to_char_type(c);

         if (!_unbuffered && pptr() < epptr()) {  // Guard against recursion.

             return sputc(byte);

         } else {

             if (PR_Write(_fd, &byte, 1) != 1) {

                 return traits_type::eof();

             }

         }

     }

     return traits_type::not_eof(c);

 }

 bool PRfilebuf::allocate()

 {

     char_type *buf = new(nothrow) char_type[BUFSIZ];

     if (buf == NULL) {

         return false;

     }

     setb(buf, buf + BUFSIZ, true);

     return true;

 }

 void PRfilebuf::setb(char_type *buf_base, char_type *buf_end, bool user_buf)

 {

     if (_buf_base && !_user_buf) {

         delete[] _buf_base;

     }

     _buf_base = buf_base;

     _buf_end = buf_end;

     _user_buf = user_buf;

 }

 PRifstream::PRifstream():

     istream(NULL),

     _filebuf()

 {

     init(&_filebuf);

 }

 PRifstream::PRifstream(PRFileDesc *fd):

     istream(NULL),

     _filebuf(fd)

 {

     init(&_filebuf);

 }

 PRifstream::PRifstream(PRFileDesc *fd, char_type *ptr, streamsize len):

     istream(NULL),

     _filebuf(fd, ptr, len)

 {

     init(&_filebuf);

 }

 PRifstream::PRifstream(const char *name, openmode flags, PRIntn mode):

     istream(NULL),

     _filebuf()

 {

     init(&_filebuf);

     if (!_filebuf.open(name, flags | in, mode)) {

         setstate(failbit);

     }

 }

 PRifstream::~PRifstream() { }

 void PRifstream::open(const char *name, openmode flags, PRIntn mode)

 {

     if (is_open() || !_filebuf.open(name, flags | in, mode)) {

         setstate(failbit);

     }

 }

 void PRifstream::attach(PRFileDesc *fd)

 {

     if (!_filebuf.attach(fd)) {

         setstate(failbit);

     }

 }

 void PRifstream::close()

 {

     if (_filebuf.close() == NULL) {

         setstate(failbit);

     }

 }

 PRofstream::PRofstream():

     ostream(NULL),

     _filebuf()

 {

     init(&_filebuf);

 }

 PRofstream::PRofstream(PRFileDesc *fd):

     ostream(NULL),

     _filebuf(fd)

 {

     init(&_filebuf);

 }

 PRofstream::PRofstream(PRFileDesc *fd, char_type *ptr, streamsize len):

     ostream(NULL),

     _filebuf(fd, ptr, len)

 {

     init(&_filebuf);

 }

 PRofstream::PRofstream(const char *name, openmode flags, PRIntn mode):

     ostream(NULL),

     _filebuf()

 {

     init(&_filebuf);

     if (!_filebuf.open(name, flags | out, mode)) {

         setstate(failbit);

     }

 }

 PRofstream::~PRofstream() { }

 void PRofstream::open(const char *name, openmode flags, PRIntn mode)

 {

     if (is_open() || !_filebuf.open(name, flags | out, mode)) {

         setstate(failbit);

     }

 }

 void PRofstream::attach(PRFileDesc *fd)

 {

     if (!_filebuf.attach(fd)) {

         setstate(failbit);

     }

 }

 void PRofstream::close()

 {

     if (_filebuf.close() == NULL) {

         setstate(failbit);

     }

 }

 PRfstream::PRfstream():

     iostream(NULL),

     _filebuf()

 {

     init(&_filebuf);

 }

 PRfstream::PRfstream(PRFileDesc *fd):

     iostream(NULL),

     _filebuf(fd)

 {

     init(&_filebuf);

 }

 PRfstream::PRfstream(PRFileDesc *fd, char_type *ptr, streamsize len):

     iostream(NULL),

     _filebuf(fd, ptr, len)

 {

     init(&_filebuf);

 }

 PRfstream::PRfstream(const char *name, openmode flags, PRIntn mode):

     iostream(NULL),

     _filebuf()

 {

     init(&_filebuf);

     if (!_filebuf.open(name, flags | in | out, mode)) {

         setstate(failbit);

     }

 }

 PRfstream::~PRfstream() { }

 void PRfstream::open(const char *name, openmode flags, PRIntn mode)

 {

     if (is_open() || !_filebuf.open(name, flags | in | out, mode)) {

         setstate(failbit);

     }

 }

 void PRfstream::attach(PRFileDesc *fd)

 {

     if (!_filebuf.attach(fd)) {

         setstate(failbit);

     }

 }

 void PRfstream::close()

 {

     if (_filebuf.close() == NULL) {

         setstate(failbit);

     }

 }