diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/base/SConscript | 1 | ||||
| -rw-r--r-- | src/base/atomicio.cc | 92 | ||||
| -rw-r--r-- | src/base/atomicio.hh | 44 | ||||
| -rw-r--r-- | src/base/circlebuf.cc | 29 | ||||
| -rw-r--r-- | src/dev/terminal.cc | 18 |
5 files changed, 157 insertions, 27 deletions
diff --git a/src/base/SConscript b/src/base/SConscript index f9d936d84..c09fdc976 100644 --- a/src/base/SConscript +++ b/src/base/SConscript @@ -31,6 +31,7 @@ Import('*') Source('annotate.cc') +Source('atomicio.cc') Source('bigint.cc') Source('circlebuf.cc') Source('cprintf.cc') diff --git a/src/base/atomicio.cc b/src/base/atomicio.cc new file mode 100644 index 000000000..3f3e6d6f0 --- /dev/null +++ b/src/base/atomicio.cc @@ -0,0 +1,92 @@ +/* + * Copyright (c) 2008 The Hewlett-Packard Development Company + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Nathan Binkert + */ + +#include <cerrno> +#include <cstdio> + +#include "base/atomicio.hh" + +ssize_t +atomic_read(int fd, void *s, size_t n) +{ + char *p = reinterpret_cast<char *>(s); + ssize_t pos = 0; + + // Keep reading until we've gotten all of the data. + while (n > pos) { + ssize_t result = read(fd, p + pos, n - pos); + + // We didn't get any more data, so we should probably punt, + // otherwise we'd just keep spinning + if (result == 0) + break; + + // If there was an error, try again on EINTR/EAGAIN, pass the + // error up otherwise. + if (result == -1) { + if (errno == EINTR || errno == EAGAIN) + continue; + return result; + } + + pos += result; + } + + return pos; +} + +ssize_t +atomic_write(int fd, const void *s, size_t n) +{ + const char *p = reinterpret_cast<const char *>(s); + ssize_t pos = 0; + + // Keep writing until we've written all of the data + while (n > pos) { + ssize_t result = write(fd, p + pos, n - pos); + + // We didn't manage to write anything this time, so we should + // probably punt, otherwise we'd just keep spinning + if (result == 0) + break; + + // If there was an error, try again on EINTR/EAGAIN, pass the + // error up otherwise. + if (result == -1) { + if (errno == EINTR || errno == EAGAIN) + continue; + return result; + } + + pos += result; + } + + return pos; +} diff --git a/src/base/atomicio.hh b/src/base/atomicio.hh new file mode 100644 index 000000000..5e703f315 --- /dev/null +++ b/src/base/atomicio.hh @@ -0,0 +1,44 @@ +/* + * Copyright (c) 2008 The Hewlett-Packard Development Company + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Nathan Binkert + */ + +#ifndef __BASE_ATOMICIO_HH__ +#define __BASE_ATOMICIO_HH__ + +#include <unistd.h> + +// These functions keep reading/writing, if possible, until all data +// has been transferred. Basically, try again when there's no error, +// but there is data left also retry on EINTR. +// This function blocks until it is done. + +ssize_t atomic_read(int fd, void *s, size_t n); +ssize_t atomic_write(int fd, const void *s, size_t n); + +#endif // __BASE_ATOMICIO_HH__ diff --git a/src/base/circlebuf.cc b/src/base/circlebuf.cc index a0c015671..d42bb11c3 100644 --- a/src/base/circlebuf.cc +++ b/src/base/circlebuf.cc @@ -29,12 +29,11 @@ */ #include <algorithm> +#include <cstdio> +#include <cstring> #include <string> -#include <stdio.h> -#include <string.h> -#include <unistd.h> - +#include "base/atomicio.hh" #include "base/circlebuf.hh" #include "base/cprintf.hh" #include "base/intmath.hh" @@ -59,8 +58,8 @@ CircleBuf::dump() cprintf("start = %10d, stop = %10d, buflen = %10d\n", _start, _stop, _buflen); fflush(stdout); - ::write(STDOUT_FILENO, _buf, _buflen); - ::write(STDOUT_FILENO, "<\n", 2); + atomic_write(STDOUT_FILENO, _buf, _buflen); + atomic_write(STDOUT_FILENO, "<\n", 2); } void @@ -106,19 +105,19 @@ CircleBuf::read(int fd, int len) if (_stop > _start) { len = min(len, _stop - _start); - ::write(fd, _buf + _start, len); + atomic_write(fd, _buf + _start, len); _start += len; } else { int endlen = _buflen - _start; if (endlen > len) { - ::write(fd, _buf + _start, len); + atomic_write(fd, _buf + _start, len); _start += len; } else { - ::write(fd, _buf + _start, endlen); + atomic_write(fd, _buf + _start, endlen); _start = min(len - endlen, _stop); - ::write(fd, _buf, _start); + atomic_write(fd, _buf, _start); } } } @@ -129,11 +128,11 @@ CircleBuf::read(int fd) _size = 0; if (_stop > _start) { - ::write(fd, _buf + _start, _stop - _start); + atomic_write(fd, _buf + _start, _stop - _start); } else { - ::write(fd, _buf + _start, _buflen - _start); - ::write(fd, _buf, _stop); + atomic_write(fd, _buf + _start, _buflen - _start); + atomic_write(fd, _buf, _stop); } _start = _stop; @@ -159,9 +158,9 @@ void CircleBuf::readall(int fd) { if (_rollover) - ::write(fd, _buf + _stop, _buflen - _stop); + atomic_write(fd, _buf + _stop, _buflen - _stop); - ::write(fd, _buf, _stop); + atomic_write(fd, _buf, _stop); _start = _stop; } diff --git a/src/dev/terminal.cc b/src/dev/terminal.cc index 58371a2bd..8c18e3bbc 100644 --- a/src/dev/terminal.cc +++ b/src/dev/terminal.cc @@ -35,16 +35,17 @@ #include <sys/ioctl.h> #include <sys/termios.h> -#include <sys/types.h> #include <errno.h> #include <poll.h> #include <unistd.h> +#include <cctype> #include <iostream> #include <fstream> #include <sstream> #include <string> +#include "base/atomicio.hh" #include "base/misc.hh" #include "base/output.hh" #include "base/socket.hh" @@ -156,7 +157,7 @@ Terminal::accept() int fd = listener.accept(true); if (data_fd != -1) { char message[] = "terminal already attached!\n"; - ::write(fd, message, sizeof(message)); + atomic_write(fd, message, sizeof(message)); ::close(fd); return; } @@ -238,16 +239,9 @@ Terminal::write(const uint8_t *buf, size_t len) if (data_fd < 0) panic("Terminal not properly attached.\n"); - size_t ret; - for (;;) { - ret = ::write(data_fd, buf, len); - - if (ret >= 0) - break; - - if (errno != EINTR) - detach(); - } + ssize_t ret = atomic_write(data_fd, buf, len); + if (ret < len) + detach(); return ret; } |