source: cpp/common/virtfile/stringfile.cpp @ 999

// This file is a part of Framsticks SDK.  http://www.framsticks.com/
// Copyright (C) 1999-2015  Maciej Komosinski and Szymon Ulatowski.
// See LICENSE.txt for details.

#include "stringfile.h"
#include <stdio.h>
#include <errno.h> //EINVAL

size_t StringFILE::Vread(void *ptr, size_t size, size_t nmemb)
{
        int have = int(str.size()) - pos;
        if (have <= 0) return 0;
        int need = (int)(size*nmemb);
        if (need > have) { nmemb = have / size; need = (int)(size*nmemb); }
        memcpy(ptr, str.c_str() + pos, need);
        pos += need;
        return nmemb;
}

int StringFILE::Vgetc()
{
        if (pos >= int(str.size()))
                return EOF;
        else
                return str.operator[]((int)pos++);
}

char *StringFILE::Vgets(char *s, int size)
{
        int have = int(str.size()) - pos;
        if (have <= 0) return 0;
        if (size < 0) size = 0;
        if (have > size) have = size - 1;
        const char* src = str.c_str() + pos;
        char *dest = s;
        while (have-- > 0)
        {
                *(dest++) = *(src++); pos++;
                if (dest[-1] == '\n') break;
        }
        *dest = 0;
        return s;
}

int StringFILE::Vseek(long offset, int whence)
{
        switch (whence)
        {
        case SEEK_SET: pos = offset; break;
        case SEEK_CUR: pos += offset; break;
        case SEEK_END: pos = int(str.size()) - offset; break;
        default: return EINVAL;
        }
        if (pos < 0) pos = 0; else if (pos > int(str.size())) pos = int(str.size());
        return 0;
}

const char StringFileSystem::PREFIX[] = "string://";

bool StringFileSystem::isStringPath(const char* path)
{
        return !strncmp(path, PREFIX, sizeof(PREFIX) - 1);
}

VirtFILE *StringFileSystem::Vfopen(const char* path, const char*mode)
{
        if ((*mode == 'r') && isStringPath(path))
        {
                return new StringFILE2(string(path + sizeof(PREFIX) - 1));
        }
        return (chain != NULL) ? chain->Vfopen(path, mode) : NULL;
}