FileStub.cpp

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#include <FpConfig.hpp>
#include <Os/File.hpp>
#include <Fw/Types/Assert.hpp>
#include <Os/Stubs/FileStubs.hpp>
 
#include <cerrno>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
 
#include <cstring>
#include <cstdio>
 
namespace Os {
 
    static ReadInterceptor readInterceptor = nullptr;
    static void *readInterceptorPtr = nullptr;
 
    static WriteInterceptor writeInterceptor = nullptr;
    static void *writeInterceptorPtr = nullptr;
 
    static OpenInterceptor openInterceptor = nullptr;
    static void *openInterceptorPtr = nullptr;
 
    static SeekInterceptor seekInterceptor = nullptr;
    static void *seekInterceptorPtr = nullptr;
 
    static NATIVE_INT_TYPE lastError = 0;
 
    void registerReadInterceptor(ReadInterceptor funcPtr, void *ptr) {
        readInterceptor = funcPtr;
        readInterceptorPtr = ptr;
    }
 
    void clearReadInterceptor() {
        readInterceptor = nullptr;
    }
 
    void registerWriteInterceptor(WriteInterceptor funcPtr, void *ptr) {
        writeInterceptor = funcPtr;
        writeInterceptorPtr = ptr;
    }
 
    void clearWriteInterceptor() {
        writeInterceptor = nullptr;
    }
 
    void registerOpenInterceptor(OpenInterceptor funcPtr, void *ptr) {
        openInterceptor = funcPtr;
        openInterceptorPtr = ptr;
    }
 
    void clearOpenInterceptor() {
        openInterceptor = nullptr;
    }
 
    void registerSeekInterceptor(SeekInterceptor funcPtr, void *ptr) {
        seekInterceptor = funcPtr;
        seekInterceptorPtr = ptr;
    }
 
    void clearSeekInterceptor() {
        seekInterceptor = nullptr;
    }
 
    void setLastError(NATIVE_INT_TYPE error) {
        lastError = error;
    }
 
 
    File::File() :m_fd(0),m_mode(OPEN_NO_MODE),m_lastError(0) {
    }
 
    File::~File() {
        if (this->m_mode != OPEN_NO_MODE) {
            this->close();
        }
    }
 
    File::Status File::open(const char* fileName, File::Mode mode) {
      return this->open(fileName, mode, true);
    }
 
    File::Status File::open(const char* fileName, File::Mode mode, bool include_excl) {
 
        if (openInterceptor) {
            File::Status stat;
            if (not openInterceptor(stat,fileName,mode,openInterceptorPtr)) {
                return stat;
            }
        }
 
        NATIVE_INT_TYPE flags = 0;
        Status stat = OP_OK;
 
        switch (mode) {
            case OPEN_READ:
                flags = O_RDONLY;
                break;
            case OPEN_WRITE:
                flags = O_WRONLY | O_CREAT | O_TRUNC;
                break;
            case OPEN_SYNC_WRITE:
                flags = O_WRONLY | O_CREAT | O_SYNC;
                break;
            case OPEN_SYNC_DIRECT_WRITE:
                flags = O_WRONLY | O_CREAT | O_DSYNC
#ifdef __linux__
                        | O_DIRECT;
#else
                ;
#endif
                break;
            case OPEN_CREATE:
                flags = O_WRONLY | O_CREAT | O_TRUNC;
                if(include_excl) {
                    flags |= O_EXCL;
                }
                break;
            default:
                FW_ASSERT(0,mode);
                break;
        }
 
        NATIVE_INT_TYPE userFlags =
#ifdef __VXWORKS__
        0;
#else
        S_IRUSR|S_IWRITE;
#endif
        NATIVE_INT_TYPE fd = ::open(fileName,flags,userFlags);
 
        if (-1 == fd) {
            this->m_lastError = errno;
            switch (errno) {
                case ENOSPC:
                    stat = NO_SPACE;
                    break;
                case ENOENT:
                    stat = DOESNT_EXIST;
                    break;
                case EACCES:
                    stat = NO_PERMISSION;
                    break;
                default:
                    stat = OTHER_ERROR;
                    break;
            }
        }
 
        this->m_mode = mode;
        this->m_fd = fd;
        return stat;
    }
 
    File::Status File::prealloc(NATIVE_INT_TYPE offset, NATIVE_INT_TYPE len) {
        // make sure it has been opened
        if (OPEN_NO_MODE == this->m_mode) {
            return NOT_OPENED;
        }
 
        File::Status fileStatus = OP_OK;
 
#ifdef __linux__
        NATIVE_INT_TYPE stat = posix_fallocate(this->m_fd, offset, len);
 
        if (stat) {
            switch (stat) {
                case ENOSPC:
                case EFBIG:
                    fileStatus = NO_SPACE;
                    break;
                case EBADF:
                    fileStatus = DOESNT_EXIST;
                    break;
                default:
                    fileStatus = OTHER_ERROR;
                    break;
            }
        }
#endif
 
        return fileStatus;
    }
 
    File::Status File::seek(NATIVE_INT_TYPE offset, bool absolute) {
 
        if (seekInterceptor) {
            File::Status stat;
            if (not seekInterceptor(stat,offset,absolute,seekInterceptorPtr)) {
                return stat;
            }
        }
 
 
        // make sure it has been opened
        if (OPEN_NO_MODE == this->m_mode) {
            return NOT_OPENED;
        }
 
        Status stat = OP_OK;
        NATIVE_INT_TYPE whence = absolute?SEEK_SET:SEEK_CUR;
 
        off_t act_off = ::lseek(this->m_fd,offset,whence);
 
        // No error would be a normal one for this simple
        // class, so return other error
        if (act_off != offset) {
            if (-1 == act_off) {
                this->m_lastError = errno;
                stat = OTHER_ERROR;
            } else {
                stat = BAD_SIZE;
            }
        }
 
        return stat;
    }
 
    File::Status File::read(void * buffer, NATIVE_INT_TYPE &size, bool waitForFull) {
 
        FW_ASSERT(buffer);
 
        if (readInterceptor) {
            File::Status stat;
            if (not readInterceptor(stat,buffer,size,waitForFull,readInterceptorPtr)) {
                return stat;
            }
        }
 
        // make sure it has been opened
        if (OPEN_NO_MODE == this->m_mode) {
            return NOT_OPENED;
        }
 
        NATIVE_INT_TYPE accSize = 0; // accumulated size
 
        Status stat = OP_OK;
 
        NATIVE_INT_TYPE maxIters = size*2; // loop limit; couldn't block more times than number of bytes
 
        while (maxIters > 0) {
 
            ssize_t readSize = ::read(this->m_fd,
#ifdef __VXWORKS__
           static_cast<char*>(buffer)
#else
               buffer
#endif
               ,size-accSize);
 
            if (readSize != size-accSize) {
                // could be an error
                if (-1 == readSize) {
                    switch (errno) {
                        case EINTR: // read was interrupted
                            maxIters--; // decrement loop count
                            continue;
                        default:
                            stat = OTHER_ERROR;
                            break;
                    }
                    this->m_lastError = errno;
                    accSize = 0;
                    break; // break out of while loop
                } else if (0 == readSize) { // end of file
                    accSize = 0;
                    break;
                } else { // partial read so adjust read point and size
                    accSize += readSize;
                    if (not waitForFull) {
                        break; // break out of while loop
                    } else {
                        // in order to move the pointer ahead, we need to cast it
                        U8* charPtr = static_cast<U8*>(buffer);
                        charPtr = &charPtr[readSize];
                        buffer = static_cast<void*>(charPtr);
                    }
                    maxIters--; // decrement loop count
                }
 
            } else { // got number we wanted
                accSize += readSize;
                break; // break out of while loop
            }
 
            maxIters--; // decrement loop count
 
        } // end read while loop
 
        // make sure we didn't exceed loop count
        FW_ASSERT(maxIters > 0);
 
        size = accSize;
 
        return stat;
    }
 
    File::Status File::write(const void * buffer, NATIVE_INT_TYPE &size, bool waitForDone) {
 
        if (writeInterceptor) {
            File::Status stat;
            if (not writeInterceptor(stat,buffer,size,waitForDone,writeInterceptorPtr)) {
                return stat;
            }
        }
 
        // make sure it has been opened
        if (OPEN_NO_MODE == this->m_mode) {
            return NOT_OPENED;
        }
 
        Status stat = OP_OK;
        // just check for EINTR
        NATIVE_INT_TYPE maxIters = size*2; // loop limit; couldn't block more times than number of bytes
        while (maxIters > 0) {
            NATIVE_INT_TYPE writeSize = ::write(this->m_fd,
#ifdef __VXWORKS__
           static_cast<char*>(const_cast<void*>(buffer)) // Ugly, but that's how VxWorks likes to roll...
#else
               buffer
#endif
               ,size);
            if (-1 == writeSize) {
                switch (errno) {
                    case EINTR: // write was interrupted
                        maxIters--; // decrement loop count
                        continue;
                    case ENOSPC:
                        stat = NO_SPACE;
                        break;
                    default:
                        stat = OTHER_ERROR;
                        break;
                }
                this->m_lastError = errno;
                break; // break out of while loop
            } else {
                size = writeSize;
                break; // break out of while loop
            }
        }
 
        return stat;
    }
 
    // NOTE(mereweth) - see http://lkml.iu.edu/hypermail/linux/kernel/1005.2/01845.html
    // recommendation from Linus Torvalds, but doesn't seem to be that fast
    File::Status File::bulkWrite(const void * buffer, NATIVE_UINT_TYPE &totalSize,
                                 NATIVE_INT_TYPE chunkSize) {
#ifdef __linux__
        const NATIVE_UINT_TYPE startPosition = lseek(this->m_fd, 0, SEEK_CUR);
#endif
        NATIVE_UINT_TYPE newBytesWritten = 0;
 
        for (NATIVE_UINT_TYPE idx = 0; idx < totalSize; idx += chunkSize) {
            NATIVE_INT_TYPE size = chunkSize;
            // if we're on the last iteration and length isn't a multiple of chunkSize
            if (idx + chunkSize > totalSize) {
                size = totalSize - idx;
            }
            const NATIVE_INT_TYPE toWrite = size;
            const Os::File::Status fileStatus = this->write(buffer, size, false);
            if (!(fileStatus == Os::File::OP_OK
                  && size == static_cast<NATIVE_INT_TYPE>(toWrite))) {
                totalSize = newBytesWritten;
                return fileStatus;
            }
 
#ifdef __linux__
            sync_file_range(this->m_fd,
                            startPosition + newBytesWritten,
                            chunkSize,
                            SYNC_FILE_RANGE_WRITE);
 
            if (newBytesWritten) {
                sync_file_range(this->m_fd,
                                startPosition + newBytesWritten - chunkSize,
                                chunkSize,
                                SYNC_FILE_RANGE_WAIT_BEFORE
                                | SYNC_FILE_RANGE_WRITE
                                | SYNC_FILE_RANGE_WAIT_AFTER);
            }
#endif
 
            newBytesWritten += toWrite;
        }
 
        totalSize = newBytesWritten;
        return OP_OK;
    }
 
    File::Status File::flush() {
        // make sure it has been opened
        if (OPEN_NO_MODE == this->m_mode) {
            return NOT_OPENED;
        }
 
        File::Status stat = OP_OK;
 
        if (-1 == fsync(this->m_fd)) {
            switch (errno) {
                case ENOSPC:
                    stat = NO_SPACE;
                    break;
                default:
                    stat = OTHER_ERROR;
                    break;
            }
        }
 
        return stat;
    }
 
    void File::close() {
        (void)::close(this->m_fd);
        this->m_mode = OPEN_NO_MODE;
    }
 
    NATIVE_INT_TYPE File::getLastError() {
        return lastError;
    }
 
    const char* File::getLastErrorString() {
        return strerror(this->m_lastError);
    }
 
 
 
}