34 lines
919 B
34 lines
919 B
#ifndef DELTA_H |
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#define DELTA_H |
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/* handling of delta buffers */ |
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extern void *diff_delta(void *from_buf, unsigned long from_size, |
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void *to_buf, unsigned long to_size, |
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unsigned long *delta_size, unsigned long max_size); |
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extern void *patch_delta(void *src_buf, unsigned long src_size, |
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void *delta_buf, unsigned long delta_size, |
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unsigned long *dst_size); |
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/* the smallest possible delta size is 4 bytes */ |
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#define DELTA_SIZE_MIN 4 |
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/* |
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* This must be called twice on the delta data buffer, first to get the |
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* expected reference buffer size, and again to get the result buffer size. |
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*/ |
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static inline unsigned long get_delta_hdr_size(const unsigned char **datap) |
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{ |
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const unsigned char *data = *datap; |
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unsigned char cmd = *data++; |
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unsigned long size = cmd & ~0x80; |
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int i = 7; |
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while (cmd & 0x80) { |
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cmd = *data++; |
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size |= (cmd & ~0x80) << i; |
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i += 7; |
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} |
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*datap = data; |
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return size; |
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} |
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#endif
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