Coverage Report

Created: 2024-09-08 06:24

/src/git/delta.h
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Source (jump to first uncovered line)
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#ifndef DELTA_H
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#define DELTA_H
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/* opaque object for delta index */
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struct delta_index;
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/*
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 * create_delta_index: compute index data from given buffer
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 *
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 * This returns a pointer to a struct delta_index that should be passed to
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 * subsequent create_delta() calls, or to free_delta_index().  A NULL pointer
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 * is returned on failure.  The given buffer must not be freed or altered
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 * before free_delta_index() is called.  The returned pointer must be freed
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 * using free_delta_index().
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 */
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struct delta_index *
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create_delta_index(const void *buf, unsigned long bufsize);
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/*
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 * free_delta_index: free the index created by create_delta_index()
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 *
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 * Given pointer must be what create_delta_index() returned, or NULL.
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 */
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void free_delta_index(struct delta_index *index);
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/*
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 * sizeof_delta_index: returns memory usage of delta index
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 *
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 * Given pointer must be what create_delta_index() returned, or NULL.
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 */
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unsigned long sizeof_delta_index(struct delta_index *index);
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/*
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 * create_delta: create a delta from given index for the given buffer
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 *
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 * This function may be called multiple times with different buffers using
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 * the same delta_index pointer.  If max_delta_size is non-zero and the
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 * resulting delta is to be larger than max_delta_size then NULL is returned.
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 * On success, a non-NULL pointer to the buffer with the delta data is
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 * returned and *delta_size is updated with its size.  The returned buffer
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 * must be freed by the caller.
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 */
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void *
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create_delta(const struct delta_index *index,
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       const void *buf, unsigned long bufsize,
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       unsigned long *delta_size, unsigned long max_delta_size);
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/*
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 * diff_delta: create a delta from source buffer to target buffer
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 *
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 * If max_delta_size is non-zero and the resulting delta is to be larger
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 * than max_delta_size then NULL is returned.  On success, a non-NULL
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 * pointer to the buffer with the delta data is returned and *delta_size is
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 * updated with its size.  The returned buffer must be freed by the caller.
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 */
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static inline void *
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diff_delta(const void *src_buf, unsigned long src_bufsize,
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     const void *trg_buf, unsigned long trg_bufsize,
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     unsigned long *delta_size, unsigned long max_delta_size)
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{
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  struct delta_index *index = create_delta_index(src_buf, src_bufsize);
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  if (index) {
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    void *delta = create_delta(index, trg_buf, trg_bufsize,
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             delta_size, max_delta_size);
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    free_delta_index(index);
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    return delta;
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  }
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  return NULL;
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}
Unexecuted instantiation: fast-import.c:diff_delta
Unexecuted instantiation: index-pack.c:diff_delta
Unexecuted instantiation: pack-objects.c:diff_delta
Unexecuted instantiation: unpack-objects.c:diff_delta
Unexecuted instantiation: apply.c:diff_delta
Unexecuted instantiation: diff-delta.c:diff_delta
Unexecuted instantiation: diff.c:diff_delta
Unexecuted instantiation: packfile.c:diff_delta
Unexecuted instantiation: patch-delta.c:diff_delta
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/*
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 * patch_delta: recreate target buffer given source buffer and delta data
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 *
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 * On success, a non-NULL pointer to the target buffer is returned and
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 * *trg_bufsize is updated with its size.  On failure a NULL pointer is
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 * returned.  The returned buffer must be freed by the caller.
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 */
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void *patch_delta(const void *src_buf, unsigned long src_size,
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      const 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 source buffer size, and again to get the target 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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                 const unsigned char *top)
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{
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  const unsigned char *data = *datap;
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  size_t cmd, size = 0;
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  int i = 0;
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  do {
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    cmd = *data++;
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    size |= st_left_shift(cmd & 0x7f, i);
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    i += 7;
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  } while (cmd & 0x80 && data < top);
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  *datap = data;
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  return cast_size_t_to_ulong(size);
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}
Unexecuted instantiation: fast-import.c:get_delta_hdr_size
Unexecuted instantiation: index-pack.c:get_delta_hdr_size
Unexecuted instantiation: pack-objects.c:get_delta_hdr_size
Unexecuted instantiation: unpack-objects.c:get_delta_hdr_size
Unexecuted instantiation: apply.c:get_delta_hdr_size
Unexecuted instantiation: diff-delta.c:get_delta_hdr_size
Unexecuted instantiation: diff.c:get_delta_hdr_size
Unexecuted instantiation: packfile.c:get_delta_hdr_size
Unexecuted instantiation: patch-delta.c:get_delta_hdr_size
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#endif