SERVER-7497 refactor and rationalize mongo/util/file.h; create file.cpp

Remove the FileInterface base class.  Move the code for non-trivial members
of the File class into a new mongo/util/file.cpp.  Make the behavior of
Windows and non-Windows versions of functions match.  Test the return status
of every OS API and report all errors in detail.

1 files changed, 284 insertions, 0 deletions

diff --git a/src/mongo/util/file.cpp b/src/mongo/util/file.cpp
new file mode 100644
index 00000000000..bd721354bff
--- /dev/null
+++ b/src/mongo/util/file.cpp
@@ -0,0 +1,284 @@
+/**   Copyright 2009 10gen Inc.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include "mongo/util/file.h"
+
+#include <boost/cstdint.hpp>
+#include <boost/filesystem/operations.hpp>
+#include <iostream>
+#include <string>
+
+#ifndef _WIN32
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <sys/types.h>
+#endif
+
+#include "mongo/platform/basic.h"
+#include "mongo/platform/cstdint.h"
+#include "mongo/util/allocator.h"
+#include "mongo/util/assert_util.h"
+#include "mongo/util/log.h"
+#include "mongo/util/mongoutils/str.h"
+#include "mongo/util/text.h"
+
+namespace mongo {
+
+#if defined(_WIN32)
+
+    File::File()
+        : _bad(true), _handle(INVALID_HANDLE_VALUE) {}
+
+    File::~File() {
+        if (is_open()) {
+            CloseHandle(_handle);
+        }
+        _handle = INVALID_HANDLE_VALUE;
+    }
+
+    boost::intmax_t File::freeSpace(const std::string& path) {
+        ULARGE_INTEGER avail;
+        if (GetDiskFreeSpaceExW(toWideString(path.c_str()).c_str(),
+                               &avail,      // bytes available to caller
+                               NULL,        // ptr to returned total size
+                               NULL)) {     // ptr to returned total free
+            return avail.QuadPart;
+        }
+        DWORD dosError = GetLastError();
+        log() << "In File::freeSpace(), GetDiskFreeSpaceEx for '" << path
+              << "' failed with " << errnoWithDescription(dosError) << std::endl;
+        return -1;
+    }
+
+    void File::fsync() const {
+        if (FlushFileBuffers(_handle) == 0) {
+            DWORD dosError = GetLastError();
+            log() << "In File::fsync(), FlushFileBuffers for '" << _name
+                  << "' failed with " << errnoWithDescription(dosError) << std::endl;
+        }
+    }
+
+    bool File::is_open() const { return _handle != INVALID_HANDLE_VALUE; }
+
+    fileofs File::len() {
+        LARGE_INTEGER li;
+        if (GetFileSizeEx(_handle, &li)) {
+            return li.QuadPart;
+        }
+        _bad = true;
+        DWORD dosError = GetLastError();
+        log() << "In File::len(), GetFileSizeEx for '" << _name
+              << "' failed with " << errnoWithDescription(dosError) << std::endl;
+        return 0;
+    }
+
+    void File::open(const char* filename, bool readOnly, bool direct) {
+        _name = filename;
+        _handle = CreateFileW(toNativeString(filename).c_str(),                 // filename
+                              (readOnly ? 0 : GENERIC_WRITE) | GENERIC_READ,    // desired access
+                              FILE_SHARE_WRITE | FILE_SHARE_READ,               // share mode
+                              NULL,                                             // security
+                              OPEN_ALWAYS,                                      // create or open
+                              FILE_ATTRIBUTE_NORMAL,                            // file attributes
+                              NULL);                                            // template
+        _bad = !is_open();
+        if (_bad) {
+            DWORD dosError = GetLastError();
+            log() << "In File::open(), CreateFileW for '" << _name
+                  << "' failed with " << errnoWithDescription(dosError) << std::endl;
+        }
+    }
+
+    void File::read(fileofs o, char* data, unsigned len) {
+        LARGE_INTEGER li;
+        li.QuadPart = o;
+        if (SetFilePointerEx(_handle, li, NULL, FILE_BEGIN) == 0) {
+            _bad = true;
+            DWORD dosError = GetLastError();
+            log() << "In File::read(), SetFilePointerEx for '" << _name
+                  << "' tried to set the file pointer to " << o
+                  << " but failed with " << errnoWithDescription(dosError) << std::endl;
+            return;
+        }
+        DWORD bytesRead;
+        if (!ReadFile(_handle, data, len, &bytesRead, 0)) {
+            _bad = true;
+            DWORD dosError = GetLastError();
+            log() << "In File::read(), ReadFile for '" << _name
+                  << "' failed with " << errnoWithDescription(dosError) << std::endl;
+        }
+        else if (bytesRead != len) {
+            _bad = true;
+            msgasserted(10438,
+                        mongoutils::str::stream() << "In File::read(), ReadFile for '" << _name
+                                                  << "' read " << bytesRead
+                                                  << " bytes while trying to read " << len
+                                                  << " bytes starting at offset " << o
+                                                  << ", truncated file?");
+        }
+    }
+
+    void File::truncate(fileofs size) {
+        if (len() <= size) {
+            return;
+        }
+        LARGE_INTEGER li;
+        li.QuadPart = size;
+        if (SetFilePointerEx(_handle, li, NULL, FILE_BEGIN) == 0) {
+            _bad = true;
+            DWORD dosError = GetLastError();
+            log() << "In File::truncate(), SetFilePointerEx for '" << _name
+                  << "' tried to set the file pointer to " << size
+                  << " but failed with " << errnoWithDescription(dosError) << std::endl;
+            return;
+        }
+        if (SetEndOfFile(_handle) == 0) {
+            _bad = true;
+            DWORD dosError = GetLastError();
+            log() << "In File::truncate(), SetEndOfFile for '" << _name
+                  << "' failed with " << errnoWithDescription(dosError) << std::endl;
+        }
+    }
+
+    void File::write(fileofs o, const char* data, unsigned len) {
+        LARGE_INTEGER li;
+        li.QuadPart = o;
+        if (SetFilePointerEx(_handle, li, NULL, FILE_BEGIN) == 0) {
+            _bad = true;
+            DWORD dosError = GetLastError();
+            log() << "In File::write(), SetFilePointerEx for '" << _name
+                  << "' tried to set the file pointer to " << o
+                  << " but failed with " << errnoWithDescription(dosError) << std::endl;
+            return;
+        }
+        DWORD bytesWritten;
+        if (WriteFile(_handle, data, len, &bytesWritten, NULL) == 0) {
+            _bad = true;
+            DWORD dosError = GetLastError();
+            log() << "In File::write(), WriteFile for '" << _name
+                  << "' tried to write " << len
+                  << " bytes but only wrote " << bytesWritten
+                  << " bytes, failing with " << errnoWithDescription(dosError) << std::endl;
+        }
+    }
+
+#else // _WIN32
+
+    File::File()
+        : _bad(true), _fd(-1) {}
+
+    File::~File() {
+        if (is_open()) {
+            ::close(_fd);
+        }
+        _fd = -1;
+    }
+
+    boost::intmax_t File::freeSpace(const std::string& path) {
+        struct statvfs info;
+        if (statvfs(path.c_str(), &info) == 0) {
+            return static_cast<boost::intmax_t>(info.f_bavail) * info.f_frsize;
+        }
+        log() << "In File::freeSpace(), statvfs for '" << path
+              << "' failed with " << errnoWithDescription() << std::endl;
+        return -1;
+    }
+
+    void File::fsync() const {
+        if (::fsync(_fd)) {
+            log() << "In File::fsync(), ::fsync for '" << _name
+                  << "' failed with " << errnoWithDescription() << std::endl;
+        }
+    }
+
+    bool File::is_open() const { return _fd > 0; }
+
+    fileofs File::len() {
+        off_t o = lseek(_fd, 0, SEEK_END);
+        if (o != static_cast<off_t>(-1)) {
+            return o;
+        }
+        _bad = true;
+        log() << "In File::len(), lseek for '" << _name
+              << "' failed with " << errnoWithDescription() << std::endl;
+        return 0;
+    }
+
+#ifndef O_NOATIME
+#define O_NOATIME 0
+#endif
+
+    void File::open(const char* filename, bool readOnly, bool direct) {
+        _name = filename;
+        _fd = ::open(filename,
+                     O_NOATIME | (readOnly ? O_RDONLY : (O_CREAT | O_RDWR))
+#if defined(O_DIRECT)
+                             | (direct ? O_DIRECT : 0)
+#endif
+                    ,
+                    S_IRUSR | S_IWUSR);
+        _bad = !is_open();
+        if (_bad) {
+            log() << "In File::open(), ::open for '" << _name
+                  << "' failed with " << errnoWithDescription() << std::endl;
+        }
+    }
+
+    void File::read(fileofs o, char *data, unsigned len) {
+        ssize_t bytesRead = ::pread(_fd, data, len, o);
+        if (bytesRead == -1) {
+            _bad = true;
+            log() << "In File::read(), ::pread for '" << _name
+                  << "' failed with " << errnoWithDescription() << std::endl;
+        }
+        else if (bytesRead != static_cast<ssize_t>(len)) { 
+            _bad = true;
+            msgasserted(16569,
+                        mongoutils::str::stream() << "In File::read(), ::pread for '" << _name
+                                                  << "' read " << bytesRead
+                                                  << " bytes while trying to read " << len
+                                                  << " bytes starting at offset " << o
+                                                  << ", truncated file?");
+        }
+    }
+
+    void File::truncate(fileofs size) {
+        if (len() <= size) {
+            return;
+        }
+        if (ftruncate(_fd, size) != 0) {
+            _bad = true;
+            log() << "In File::truncate(), ftruncate for '" << _name
+                  << "' tried to set the file pointer to " << size
+                  << " but failed with " << errnoWithDescription() << std::endl;
+            return;
+        }
+    }
+
+    void File::write(fileofs o, const char *data, unsigned len) {
+        ssize_t bytesWritten = ::pwrite(_fd, data, len, o);
+        if (bytesWritten != static_cast<ssize_t>(len)) {
+            _bad = true;
+            log() << "In File::write(), ::pwrite for '" << _name
+                  << "' tried to write " << len
+                  << " bytes but only wrote " << bytesWritten
+                  << " bytes, failing with " << errnoWithDescription() << std::endl;
+        }
+    }
+
+#endif // _WIN32
+
+}