mirror of https://github.com/vivier/EMILE.git
52 lines
1.0 KiB
C
52 lines
1.0 KiB
C
/*
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*
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* (c) 2005-2008 Laurent Vivier <Laurent@Vivier.EU>
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*
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*/
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#include <string.h>
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#include "libblock.h"
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#include "block.h"
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size_t block_read(stream_FILE *_file, void *ptr, size_t size)
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{
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block_FILE *file = (block_FILE*)_file;
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int part;
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int block_nb;
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int block_offset;
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int read = 0;
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int ret;
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int blocksize = file->device->get_blocksize(file->device->data);
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while (size != 0)
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{
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block_nb = (file->base +
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file->offset / blocksize) / file->buffer_size;
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block_offset = (file->base - block_nb * file->buffer_size) *
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blocksize + file->offset;
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if (block_nb != file->current)
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{
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ret = file->device->read_sector(file->device->data,
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block_nb * file->buffer_size,
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file->buffer,
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file->buffer_size * blocksize);
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if (ret == -1)
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return read;
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file->current = block_nb;
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}
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part = file->buffer_size * blocksize - block_offset;
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if (part > size)
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part = size;
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memcpy(ptr, file->buffer + block_offset, part);
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size -= part;
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ptr = (char*)ptr + part;
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file->offset += part;
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read += part;
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}
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return read;
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}
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