| # buf1 = EB_PAGE_SIZE, # lpt = # avol, avol[m3] = mapped(buf2), err = err0, m3 < # avol, ebm-vol-inv(avol), m0 + n ≤ LEB_SIZE, n ≤ # buf, bleb ≠ nobuffer → bleb.leb < # avol ∧ wbuf-cons(mkwbuf(buf1, m5, m4), avol[bleb.leb], rofs), ⌊err0⌋ ∨ err0 = ESUCCESS ⊦ ⟪buf0 := buf; if err = ESUCCESS then buf0 := copy(avol[m3].data + mkempbuf(LEB_SIZE - # avol[m3].data), m0, buf0, 0, n) else {n0 := 0; choose buf with # buf = # buf0 ∧ range=(buf0, 0, buf, 0, n0) ∧ range=(buf0, n0 + n, buf, n0 + n, # buf0 - n0 + n) in buf0 := buf}; if err = ESUCCESS ∧ buffered(m3) = bleb ∧ m0 ≤ m5 + m4 ∧ m5 ≤ m0 + n then let m = (m0 ≤ m5 ⊃ 0;m0 - m5), m1 = (m0 ≤ m5 ⊃ m5 - m0;0) in buf := copy(buf1, m, buf0, m1, min(n - m1, m4 - m))⟫ true |
# lpt = # avol, # buf1 = EB_PAGE_SIZE, avol[m3] = mapped(buf2), buf0 = buf, err = err0, m3 < # avol, ebm-vol-inv(avol), n ≤ # buf, m0 + n ≤ LEB_SIZE, bleb ≠ nobuffer → bleb.leb < # avol ∧ wbuf-cons(mkwbuf(buf1, m5, m4), avol[bleb.leb], rofs), ⌊err0⌋ ∨ err0 = ESUCCESS ⊦ ⟪if err = ESUCCESS then buf0 := copy(avol[m3].data + mkempbuf(LEB_SIZE - # avol[m3].data), m0, buf0, 0, n) else {n0 := 0; choose buf with # buf = # buf0 ∧ range=(buf0, 0, buf, 0, n0) ∧ range=(buf0, n0 + n, buf, n0 + n, # buf0 - n0 + n) in buf0 := buf}; if err = ESUCCESS ∧ buffered(m3) = bleb ∧ m0 ≤ m5 + m4 ∧ m5 ≤ m0 + n then let m = (m0 ≤ m5 ⊃ 0;m0 - m5), m1 = (m0 ≤ m5 ⊃ m5 - m0;0) in buf := copy(buf1, m, buf0, m1, min(n - m1, m4 - m))⟫ true