| err = ESUCCESS, m = m1, n + NODE_HEADER_SIZE ≤ # buf, n + m1 ≤ # buf, 2 * NODE_HEADER_SIZE ≤ m1, err = ESUCCESS → is-encoded(ndhd, subarray(buf, n, NODE_HEADER_SIZE)), err = ESUCCESS ∨ ⌊err⌋ ⊦ ⟪debug#("persistence: decode_node node of wrong size"); err := EIO; m0 := n; if err = ESUCCESS then {decode_node_headerless#(m0 + NODE_HEADER_SIZE, buf; nd, m; err); if err ≠ ESUCCESS then debug#("persistence: decode_node decoding failed") else if m ≠ ndhd.size then {debug#("persistence: decode_node size of node unexpected"); err := EINVAL}}; if err = ESUCCESS ∧ ¬ range=(buf, m0 + NODE_HEADER_SIZE + align↑(ndhd.size, 2 * NODE_HEADER_SIZE), validtrailer, 0, NODE_HEADER_SIZE) then {debug#("persistence: decode_node no validtrailer"); err := EIO}⟫ ( (err = ESUCCESS ∨ ⌊err⌋ ) ∧ ( err = ESUCCESS → (∃ buf0, buf1. subarray(buf, n, 2 * NODE_HEADER_SIZE + nd.alignedsize) = buf0 + buf1 + validtrailer ∧ is-encoded(nodeheader(node-size-headerless(nd), false), buf0) ∧ is-encoded(nd, subarray(buf1, 0, node-size-headerless(nd))) ∧ # buf1 = nd.alignedsize) ∧ m1 = 2 * NODE_HEADER_SIZE + nd.alignedsize)), align↑(ndhd.size, 2 * NODE_HEADER_SIZE) + 2 * NODE_HEADER_SIZE = m, err = ESUCCESS ∧ ndhd.ispadding |
align↑(ndhd.size, 2 * NODE_HEADER_SIZE) + 2 * NODE_HEADER_SIZE ≠ m1, is-encoded(ndhd, subarray(buf, n, NODE_HEADER_SIZE)), n + NODE_HEADER_SIZE ≤ # buf, n + m1 ≤ # buf, 2 * NODE_HEADER_SIZE ≤ m1, ¬ ndhd.ispadding ⊦ ⟪debug#("persistence: decode_node node of wrong size"); err := EIO; m0 := n; m := m1; if err = ESUCCESS then {decode_node_headerless#(m0 + NODE_HEADER_SIZE, buf; nd, m; err); if err ≠ ESUCCESS then debug#("persistence: decode_node decoding failed") else if m ≠ ndhd.size then {debug#("persistence: decode_node size of node unexpected"); err := EINVAL}}; if err = ESUCCESS ∧ ¬ range=(buf, m0 + NODE_HEADER_SIZE + align↑(ndhd.size, 2 * NODE_HEADER_SIZE), validtrailer, 0, NODE_HEADER_SIZE) then {debug#("persistence: decode_node no validtrailer"); err := EIO}⟫ ( (err = ESUCCESS ∨ ⌊err⌋ ) ∧ ( err = ESUCCESS → (∃ buf0, buf1. subarray(buf, n, 2 * NODE_HEADER_SIZE + nd.alignedsize) = buf0 + buf1 + validtrailer ∧ is-encoded(nodeheader(node-size-headerless(nd), false), buf0) ∧ is-encoded(nd, subarray(buf1, 0, node-size-headerless(nd))) ∧ # buf1 = nd.alignedsize) ∧ m1 = 2 * NODE_HEADER_SIZE + nd.alignedsize))
Used simplifier rules: ⊦ # subarray(buf, m, n) = n; (s)%is-encoded-size: ⊦ is-encoded(ndhd, buf) → # buf = NODE_HEADER_SIZE; (forward) from specification encoding-fixed-size-nonempty[encoding-node-header]