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/* Ring definitions. */ |
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#define qr(a_type) \ |
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struct { \ |
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a_type *qre_next; \ |
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a_type *qre_prev; \ |
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} |
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|
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/* Ring functions. */ |
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#define qr_new(a_qr, a_field) do { \ |
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(a_qr)->a_field.qre_next = (a_qr); \ |
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(a_qr)->a_field.qre_prev = (a_qr); \ |
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} while (0) |
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|
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#define qr_next(a_qr, a_field) ((a_qr)->a_field.qre_next) |
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|
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#define qr_prev(a_qr, a_field) ((a_qr)->a_field.qre_prev) |
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|
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#define qr_before_insert(a_qrelm, a_qr, a_field) do { \ |
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(a_qr)->a_field.qre_prev = (a_qrelm)->a_field.qre_prev; \ |
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(a_qr)->a_field.qre_next = (a_qrelm); \ |
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(a_qr)->a_field.qre_prev->a_field.qre_next = (a_qr); \ |
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(a_qrelm)->a_field.qre_prev = (a_qr); \ |
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} while (0) |
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|
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#define qr_after_insert(a_qrelm, a_qr, a_field) \ |
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do \ |
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{ \ |
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(a_qr)->a_field.qre_next = (a_qrelm)->a_field.qre_next; \ |
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(a_qr)->a_field.qre_prev = (a_qrelm); \ |
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(a_qr)->a_field.qre_next->a_field.qre_prev = (a_qr); \ |
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(a_qrelm)->a_field.qre_next = (a_qr); \ |
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} while (0) |
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|
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#define qr_meld(a_qr_a, a_qr_b, a_field) do { \ |
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void *t; \ |
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(a_qr_a)->a_field.qre_prev->a_field.qre_next = (a_qr_b); \ |
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(a_qr_b)->a_field.qre_prev->a_field.qre_next = (a_qr_a); \ |
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t = (a_qr_a)->a_field.qre_prev; \ |
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(a_qr_a)->a_field.qre_prev = (a_qr_b)->a_field.qre_prev; \ |
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(a_qr_b)->a_field.qre_prev = t; \ |
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} while (0) |
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|
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/* qr_meld() and qr_split() are functionally equivalent, so there's no need to |
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* have two copies of the code. */ |
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#define qr_split(a_qr_a, a_qr_b, a_field) \ |
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qr_meld((a_qr_a), (a_qr_b), a_field) |
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|
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#define qr_remove(a_qr, a_field) do { \ |
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(a_qr)->a_field.qre_prev->a_field.qre_next \ |
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= (a_qr)->a_field.qre_next; \ |
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(a_qr)->a_field.qre_next->a_field.qre_prev \ |
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= (a_qr)->a_field.qre_prev; \ |
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(a_qr)->a_field.qre_next = (a_qr); \ |
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(a_qr)->a_field.qre_prev = (a_qr); \ |
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} while (0) |
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|
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#define qr_foreach(var, a_qr, a_field) \ |
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for ((var) = (a_qr); \ |
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(var) != NULL; \ |
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(var) = (((var)->a_field.qre_next != (a_qr)) \ |
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? (var)->a_field.qre_next : NULL)) |
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|
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#define qr_reverse_foreach(var, a_qr, a_field) \ |
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for ((var) = ((a_qr) != NULL) ? qr_prev(a_qr, a_field) : NULL; \ |
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(var) != NULL; \ |
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(var) = (((var) != (a_qr)) \ |
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? (var)->a_field.qre_prev : NULL)) |
