The Tor Browser: nsprpub/lib/prstreams/prstrms.cpp@8bccb770b82d

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

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

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

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

     6 /*

     7  * Robin J. Maxwell 11-22-96

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

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

    10  */

    12 #include "prstrms.h"

    14 #include <cstdio>

    15 #include <cstring>

    16 #include <ios>

    17 #include <new>

    19 using std::ios_base;

    20 using std::iostream;

    21 using std::istream;

    22 using std::nothrow;

    23 using std::ostream;

    24 using std::streambuf;

    25 using std::streamsize;

    28 PRfilebuf::PRfilebuf():

    29     _fd(NULL),

    30     _opened(false),

    31     _allocated(false),

    32     _unbuffered(false),

    33     _user_buf(false),

    34     _buf_base(NULL),

    35     _buf_end(NULL) { }

    38 PRfilebuf::PRfilebuf(PRFileDesc *fd):

    39     _fd(fd),

    40     _opened(false),

    41     _allocated(false),

    42     _unbuffered(false),

    43     _user_buf(false),

    44     _buf_base(NULL),

    45     _buf_end(NULL) { }

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

    49     _fd(fd),

    50     _opened(false),

    51     _allocated(false),

    52     _unbuffered(false),

    53     _user_buf(false),

    54     _buf_base(NULL),

    55     _buf_end(NULL)

    56 {

    57     setbuf(ptr, len);

    58 }

    61 PRfilebuf::~PRfilebuf()

    62 {

    63     if (_opened) {

    64         close();

    65     } else {

    66         sync();

    67     }

    68     if (_allocated) {

    69         delete _buf_base;

    70     }

    71 }

    74 PRfilebuf *PRfilebuf::open(

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

    76 {

    77     if (_fd != NULL) {

    78         return NULL;  // Error if already open.

    79     }

    81     // Translate flags argument.

    82     PRIntn prflags = 0;

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

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

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

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

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

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

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

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

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

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

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

    96         prflags = PR_WRONLY | PR_TRUNCATE;

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

    98         prflags = PR_RDWR | PR_APPEND;

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

   100         prflags = PR_WRONLY | PR_TRUNCATE;

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

   102         prflags = PR_RDONLY;

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

   104         prflags = PR_RDWR;

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

   106         prflags = PR_RDWR | PR_TRUNCATE;

   107     } else {

   108         return NULL;  // Unrecognized flag combination.

   109     }

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

   112         return NULL;

   113     }

   115     _opened = true;

   117     if (ate &&

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

   119         close();

   120         return NULL;

   121     }

   123     return this;

   124 }

   127 PRfilebuf *PRfilebuf::attach(PRFileDesc *fd)

   128 {

   129     if (_fd != NULL) {

   130         return NULL;  // Error if already open.

   131     }

   133     _opened = false;

   134     _fd = fd;

   135     return this;

   136 }

   139 PRfilebuf *PRfilebuf::close()

   140 {

   141     if (_fd == NULL)

   142         return NULL;

   144     int status = sync();

   146     if (PR_Close(_fd) == PR_FAILURE ||

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

   148         return NULL;

   149     }

   151     _fd = NULL;

   152     return this;

   153 }

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

   157 {

   158     if (is_open() && _buf_end) {

   159         return NULL;

   160     }

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

   163         _unbuffered = true;

   164     } else {

   165         setb(ptr, ptr + len, false);

   166     }

   168     return this;

   169 }

   172 streambuf::pos_type PRfilebuf::seekoff(

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

   174 {

   175     if (PR_GetDescType(_fd) != PR_DESC_FILE) {

   176         return traits_type::eof();

   177     }

   179     PRSeekWhence whence;

   180     PRInt64 pos;

   182     switch (dir) {

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

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

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

   186         default:

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

   188     }

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

   191         return traits_type::eof();

   192     }

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

   195         return traits_type::eof();

   196     }

   198     return pos;

   199 }

   202 int PRfilebuf::sync()

   203 {

   204     if (_fd == NULL) {

   205         return traits_type::eof();

   206     }

   208     if (!_unbuffered) {

   209         // Sync write area.

   210         PRInt32 waiting;

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

   212             PRInt32 nout;

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

   214                 if (nout > 0) {

   215                     // Should set _pptr -= nout.

   216                     pbump(-nout);

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

   218                 }

   219                 return traits_type::eof();

   220             }

   221         }

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

   224         if (PR_GetDescType(_fd) == PR_DESC_FILE) {

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

   226             PROffset64 avail;

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

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

   229                     return traits_type::eof();

   230                 }

   231             }

   232         }

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

   234     }

   236     return 0;

   237 }

   240 streambuf::int_type PRfilebuf::underflow()

   241 {

   242     PRInt32 count;

   243     char_type byte;

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

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

   247     }

   249     // Make sure there is a reserve area.

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

   251         return traits_type::eof();

   252     }

   254     // Sync before new buffer created below.

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

   256         return traits_type::eof();

   257     }

   259     if (_unbuffered) {

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

   261             return traits_type::eof();

   262         }

   264         return traits_type::to_int_type(byte);

   265     }

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

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

   269     }

   271     setg(_buf_base, _buf_base, _buf_base + count);

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

   273 }

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

   277 {

   278     // Make sure there is a reserve area.

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

   280         return traits_type::eof();

   281     }

   283     // Sync before new buffer created below.

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

   285         return traits_type::eof();

   286     }

   288     if (!_unbuffered) {

   289         setp(_buf_base, _buf_end);

   290     }

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

   293         // Extract the byte to be written.

   294         // (Required on big-endian architectures.)

   295         char_type byte = traits_type::to_char_type(c);

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

   297             return sputc(byte);

   298         } else {

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

   300                 return traits_type::eof();

   301             }

   302         }

   303     }

   305     return traits_type::not_eof(c);

   306 }

   309 bool PRfilebuf::allocate()

   310 {

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

   312     if (buf == NULL) {

   313         return false;

   314     }

   316     setb(buf, buf + BUFSIZ, true);

   317     return true;

   318 }

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

   322 {

   323     if (_buf_base && !_user_buf) {

   324         delete[] _buf_base;

   325     }

   327     _buf_base = buf_base;

   328     _buf_end = buf_end;

   329     _user_buf = user_buf;

   330 }

   333 PRifstream::PRifstream():

   334     istream(NULL),

   335     _filebuf()

   336 {

   337     init(&_filebuf);

   338 }

   341 PRifstream::PRifstream(PRFileDesc *fd):

   342     istream(NULL),

   343     _filebuf(fd)

   344 {

   345     init(&_filebuf);

   346 }

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

   350     istream(NULL),

   351     _filebuf(fd, ptr, len)

   352 {

   353     init(&_filebuf);

   354 }

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

   358     istream(NULL),

   359     _filebuf()

   360 {

   361     init(&_filebuf);

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

   363         setstate(failbit);

   364     }

   365 }

   368 PRifstream::~PRifstream() { }

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

   372 {

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

   374         setstate(failbit);

   375     }

   376 }

   379 void PRifstream::attach(PRFileDesc *fd)

   380 {

   381     if (!_filebuf.attach(fd)) {

   382         setstate(failbit);

   383     }

   384 }

   387 void PRifstream::close()

   388 {

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

   390         setstate(failbit);

   391     }

   392 }

   395 PRofstream::PRofstream():

   396     ostream(NULL),

   397     _filebuf()

   398 {

   399     init(&_filebuf);

   400 }

   403 PRofstream::PRofstream(PRFileDesc *fd):

   404     ostream(NULL),

   405     _filebuf(fd)

   406 {

   407     init(&_filebuf);

   408 }

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

   412     ostream(NULL),

   413     _filebuf(fd, ptr, len)

   414 {

   415     init(&_filebuf);

   416 }

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

   420     ostream(NULL),

   421     _filebuf()

   422 {

   423     init(&_filebuf);

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

   425         setstate(failbit);

   426     }

   427 }

   430 PRofstream::~PRofstream() { }

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

   434 {

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

   436         setstate(failbit);

   437     }

   438 }

   441 void PRofstream::attach(PRFileDesc *fd)

   442 {

   443     if (!_filebuf.attach(fd)) {

   444         setstate(failbit);

   445     }

   446 }

   449 void PRofstream::close()

   450 {

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

   452         setstate(failbit);

   453     }

   454 }

   457 PRfstream::PRfstream():

   458     iostream(NULL),

   459     _filebuf()

   460 {

   461     init(&_filebuf);

   462 }

   465 PRfstream::PRfstream(PRFileDesc *fd):

   466     iostream(NULL),

   467     _filebuf(fd)

   468 {

   469     init(&_filebuf);

   470 }

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

   474     iostream(NULL),

   475     _filebuf(fd, ptr, len)

   476 {

   477     init(&_filebuf);

   478 }

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

   482     iostream(NULL),

   483     _filebuf()

   484 {

   485     init(&_filebuf);

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

   487         setstate(failbit);

   488     }

   489 }

   492 PRfstream::~PRfstream() { }

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

   496 {

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

   498         setstate(failbit);

   499     }

   500 }

   503 void PRfstream::attach(PRFileDesc *fd)

   504 {

   505     if (!_filebuf.attach(fd)) {

   506         setstate(failbit);

   507     }

   508 }

   511 void PRfstream::close()

   512 {

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

   514         setstate(failbit);

   515     }

   516 }

The Tor Browser / file revision

nsprpub/lib/prstreams/prstrms.cpp@8bccb770b82d

nsprpub/lib/prstreams/prstrms.cpp