stdio_alloc.h

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#ifndef VIRTMEM_STDIO_ALLOC_H
#define VIRTMEM_STDIO_ALLOC_H

#include "internal/alloc.h"
#include "config/config.h"

#include <errno.h>
#include <stdio.h>
#include <string.h>

namespace virtmem {

template <typename Properties = DefaultAllocProperties>
class StdioVAllocP : public VAlloc<Properties, StdioVAllocP<Properties> >
{
    FILE *ramFile;

    void doStart(void)
    {
        ramFile = tmpfile();
        if (!ramFile)
            fprintf(stderr, "Unable to open ram file!");
        this->writeZeros(0, this->getPoolSize()); // make sure it gets the right size
    }

    void doSuspend(void) { }
    void doStop(void) { if (ramFile) { fclose(ramFile); ramFile = 0; } }
    void doRead(void *data, VPtrSize offset, VPtrSize size)
    {
        if (fseek(ramFile, offset, SEEK_SET) != 0)
            fprintf(stderr, "fseek error: %s\n", strerror(errno));

        fread(data, size, 1, ramFile);
        if (ferror(ramFile))
            fprintf(stderr, "didn't read correctly: %s\n", strerror(errno));

    }

    void doWrite(const void *data, VPtrSize offset, VPtrSize size)
    {
        if (fseek(ramFile, offset, SEEK_SET) != 0)
            fprintf(stderr, "fseek error: %s\n", strerror(errno));

        fwrite(data, size, 1, ramFile);
        if (ferror(ramFile))
            fprintf(stderr, "didn't write correctly: %s\n", strerror(errno));
    }

public:
    StdioVAllocP(VPtrSize ps=VIRTMEM_DEFAULT_POOLSIZE) : ramFile(0) { this->setPoolSize(ps); }
    ~StdioVAllocP(void) { doStop(); }
};

typedef StdioVAllocP<> StdioVAlloc; 

}

#endif // VIRTMEM_STDIO_ALLOC_H