| // Copyright (c) 2003-2008 Yuta Mori All Rights Reserved. |
| // |
| // Permission is hereby granted, free of charge, to any person |
| // obtaining a copy of this software and associated documentation |
| // files (the "Software"), to deal in the Software without |
| // restriction, including without limitation the rights to use, |
| // copy, modify, merge, publish, distribute, sublicense, and/or sell |
| // copies of the Software, and to permit persons to whom the |
| // Software is furnished to do so, subject to the following |
| // conditions: |
| // |
| // The above copyright notice and this permission notice shall be |
| // included in all copies or substantial portions of the Software. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES |
| // OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT |
| // HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, |
| // WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
| // OTHER DEALINGS IN THE SOFTWARE. |
| // |
| // ChangeLog: |
| // 2016-07-22 - Initial commit and adaption to use PagedArray. |
| // --Samuel Huang <huangs@chromium.org> |
| |
| #include "courgette/third_party/divsufsort/divsufsort_private.h" |
| |
| #include <stdlib.h> |
| |
| #define BUCKET_A_SIZE (ALPHABET_SIZE) |
| #define BUCKET_B_SIZE (ALPHABET_SIZE * ALPHABET_SIZE) |
| |
| #define BUCKET_A(_c0) bucket_A[(_c0)] |
| #if ALPHABET_SIZE == 256 |
| #define BUCKET_B(_c0, _c1) (bucket_B[((_c1) << 8) | (_c0)]) |
| #define BUCKET_BSTAR(_c0, _c1) (bucket_B[((_c0) << 8) | (_c1)]) |
| #else |
| #define BUCKET_B(_c0, _c1) (bucket_B[(_c1) * ALPHABET_SIZE + (_c0)]) |
| #define BUCKET_BSTAR(_c0, _c1) (bucket_B[(_c0) * ALPHABET_SIZE + (_c1)]) |
| #endif |
| |
| namespace divsuf { |
| |
| /*- Private Functions -*/ |
| |
| namespace { |
| |
| /* Sorts suffixes of type B*. */ |
| saidx_t |
| sort_typeBstar(const sauchar_t *T, saidx_it SA, |
| saidx_t *bucket_A, saidx_t *bucket_B, |
| saidx_t n) { |
| saidx_it PAb, ISAb, buf; |
| saidx_t i, j, k, t, m, bufsize; |
| saint_t c0, c1; |
| |
| /* Initialize bucket arrays. */ |
| for(i = 0; i < static_cast<saidx_t>(BUCKET_A_SIZE); ++i) { bucket_A[i] = 0; } |
| for(i = 0; i < static_cast<saidx_t>(BUCKET_B_SIZE); ++i) { bucket_B[i] = 0; } |
| |
| /* Count the number of occurrences of the first one or two characters of each |
| type A, B and B* suffix. Moreover, store the beginning position of all |
| type B* suffixes into the array SA. */ |
| for(i = n - 1, m = n, c0 = T[n - 1]; 0 <= i;) { |
| /* type A suffix. */ |
| do { ++BUCKET_A(c1 = c0); } while((0 <= --i) && ((c0 = T[i]) >= c1)); |
| if(0 <= i) { |
| /* type B* suffix. */ |
| ++BUCKET_BSTAR(c0, c1); |
| SA[--m] = i; |
| /* type B suffix. */ |
| for(--i, c1 = c0; (0 <= i) && ((c0 = T[i]) <= c1); --i, c1 = c0) { |
| ++BUCKET_B(c0, c1); |
| } |
| } |
| } |
| m = n - m; |
| /* |
| note: |
| A type B* suffix is lexicographically smaller than a type B suffix that |
| begins with the same first two characters. |
| */ |
| |
| /* Calculate the index of start/end point of each bucket. */ |
| for(c0 = 0, i = 0, j = 0; c0 < static_cast<saint_t>(ALPHABET_SIZE); ++c0) { |
| t = i + BUCKET_A(c0); |
| BUCKET_A(c0) = i + j; /* start point */ |
| i = t + BUCKET_B(c0, c0); |
| for(c1 = c0 + 1; c1 < static_cast<saint_t>(ALPHABET_SIZE); ++c1) { |
| j += BUCKET_BSTAR(c0, c1); |
| BUCKET_BSTAR(c0, c1) = j; /* end point */ |
| i += BUCKET_B(c0, c1); |
| } |
| } |
| |
| if(0 < m) { |
| /* Sort the type B* suffixes by their first two characters. */ |
| PAb = SA + n - m; ISAb = SA + m; |
| for(i = m - 2; 0 <= i; --i) { |
| t = PAb[i], c0 = T[t], c1 = T[t + 1]; |
| SA[--BUCKET_BSTAR(c0, c1)] = i; |
| } |
| t = PAb[m - 1], c0 = T[t], c1 = T[t + 1]; |
| SA[--BUCKET_BSTAR(c0, c1)] = m - 1; |
| |
| /* Sort the type B* substrings using sssort. */ |
| buf = SA + m, bufsize = n - (2 * m); |
| for(c0 = ALPHABET_SIZE - 2, j = m; 0 < j; --c0) { |
| for(c1 = ALPHABET_SIZE - 1; c0 < c1; j = i, --c1) { |
| i = BUCKET_BSTAR(c0, c1); |
| if(1 < (j - i)) { |
| sssort(T, PAb, SA + i, SA + j, |
| buf, bufsize, 2, n, *(SA + i) == (m - 1)); |
| } |
| } |
| } |
| |
| /* Compute ranks of type B* substrings. */ |
| for(i = m - 1; 0 <= i; --i) { |
| if(0 <= SA[i]) { |
| j = i; |
| do { ISAb[SA[i]] = i; } while((0 <= --i) && (0 <= SA[i])); |
| SA[i + 1] = i - j; |
| if(i <= 0) { break; } |
| } |
| j = i; |
| do { ISAb[SA[i] = ~SA[i]] = j; } while(SA[--i] < 0); |
| ISAb[SA[i]] = j; |
| } |
| |
| /* Construct the inverse suffix array of type B* suffixes using trsort. */ |
| trsort(ISAb, SA, m, 1); |
| |
| /* Set the sorted order of tyoe B* suffixes. */ |
| for(i = n - 1, j = m, c0 = T[n - 1]; 0 <= i;) { |
| for(--i, c1 = c0; (0 <= i) && ((c0 = T[i]) >= c1); --i, c1 = c0) { } |
| if(0 <= i) { |
| t = i; |
| for(--i, c1 = c0; (0 <= i) && ((c0 = T[i]) <= c1); --i, c1 = c0) { } |
| SA[ISAb[--j]] = ((t == 0) || (1 < (t - i))) ? t : ~t; |
| } |
| } |
| |
| /* Calculate the index of start/end point of each bucket. */ |
| BUCKET_B(ALPHABET_SIZE - 1, ALPHABET_SIZE - 1) = n; /* end point */ |
| for(c0 = ALPHABET_SIZE - 2, k = m - 1; 0 <= c0; --c0) { |
| i = BUCKET_A(c0 + 1) - 1; |
| for(c1 = ALPHABET_SIZE - 1; c0 < c1; --c1) { |
| t = i - BUCKET_B(c0, c1); |
| BUCKET_B(c0, c1) = i; /* end point */ |
| |
| /* Move all type B* suffixes to the correct position. */ |
| for(i = t, j = BUCKET_BSTAR(c0, c1); |
| j <= k; |
| --i, --k) { SA[i] = SA[k]; } |
| } |
| BUCKET_BSTAR(c0, c0 + 1) = i - BUCKET_B(c0, c0) + 1; /* start point */ |
| BUCKET_B(c0, c0) = i; /* end point */ |
| } |
| } |
| |
| return m; |
| } |
| |
| /* Constructs the suffix array by using the sorted order of type B* suffixes. */ |
| void |
| construct_SA(const sauchar_t *T, saidx_it SA, |
| saidx_t *bucket_A, saidx_t *bucket_B, |
| saidx_t n, saidx_t m) { |
| saidx_it i, j, k; |
| saidx_t s; |
| saint_t c0, c1, c2; |
| |
| if(0 < m) { |
| /* Construct the sorted order of type B suffixes by using |
| the sorted order of type B* suffixes. */ |
| for(c1 = ALPHABET_SIZE - 2; 0 <= c1; --c1) { |
| /* Scan the suffix array from right to left. */ |
| for(i = SA + BUCKET_BSTAR(c1, c1 + 1), |
| j = SA + BUCKET_A(c1 + 1) - 1, k = NULL, c2 = -1; |
| i <= j; |
| --j) { |
| if(0 < (s = *j)) { |
| assert(T[s] == c1); |
| assert(((s + 1) < n) && (T[s] <= T[s + 1])); |
| assert(T[s - 1] <= T[s]); |
| *j = ~s; |
| c0 = T[--s]; |
| if((0 < s) && (T[s - 1] > c0)) { s = ~s; } |
| if(c0 != c2) { |
| if(0 <= c2) { BUCKET_B(c2, c1) = k - SA; } |
| k = SA + BUCKET_B(c2 = c0, c1); |
| } |
| assert(k < j); |
| *k-- = s; |
| } else { |
| assert(((s == 0) && (T[s] == c1)) || (s < 0)); |
| *j = ~s; |
| } |
| } |
| } |
| } |
| |
| /* Construct the suffix array by using |
| the sorted order of type B suffixes. */ |
| k = SA + BUCKET_A(c2 = T[n - 1]); |
| *k++ = (T[n - 2] < c2) ? ~(n - 1) : (n - 1); |
| /* Scan the suffix array from left to right. */ |
| for(i = SA, j = SA + n; i < j; ++i) { |
| if(0 < (s = *i)) { |
| assert(T[s - 1] >= T[s]); |
| c0 = T[--s]; |
| if((s == 0) || (T[s - 1] < c0)) { s = ~s; } |
| if(c0 != c2) { |
| BUCKET_A(c2) = k - SA; |
| k = SA + BUCKET_A(c2 = c0); |
| } |
| assert(i < k); |
| *k++ = s; |
| } else { |
| assert(s < 0); |
| *i = ~s; |
| } |
| } |
| } |
| |
| } // namespace |
| |
| /*---------------------------------------------------------------------------*/ |
| |
| /*- Function -*/ |
| |
| saint_t |
| divsufsort(const sauchar_t *T, saidx_it SA, saidx_t n) { |
| saidx_t *bucket_A, *bucket_B; |
| saidx_t m; |
| saint_t err = 0; |
| |
| /* Check arguments. */ |
| if((T == NULL) || (SA == NULL) || (n < 0)) { return -1; } |
| else if(n == 0) { return 0; } |
| else if(n == 1) { SA[0] = 0; return 0; } |
| else if(n == 2) { m = (T[0] < T[1]); SA[m ^ 1] = 0, SA[m] = 1; return 0; } |
| |
| bucket_A = (saidx_t *)malloc(BUCKET_A_SIZE * sizeof(saidx_t)); |
| bucket_B = (saidx_t *)malloc(BUCKET_B_SIZE * sizeof(saidx_t)); |
| |
| /* Suffixsort. */ |
| if((bucket_A != NULL) && (bucket_B != NULL)) { |
| m = sort_typeBstar(T, SA, bucket_A, bucket_B, n); |
| construct_SA(T, SA, bucket_A, bucket_B, n, m); |
| } else { |
| err = -2; |
| } |
| |
| free(bucket_B); |
| free(bucket_A); |
| |
| return err; |
| } |
| |
| saint_t divsufsort_include_empty(const sauchar_t *T, saidx_it SA, saidx_t n) { |
| SA[0] = n; // Manually add the empty string suffix. |
| return divsufsort(T, SA + 1, n); |
| } |
| |
| } // namespace divsuf |