| /* |
| tre-match-parallel.c - TRE parallel regex matching engine |
| |
| This software is released under a BSD-style license. |
| See the file LICENSE for details and copyright. |
| |
| */ |
| |
| /* |
| This algorithm searches for matches basically by reading characters |
| in the searched string one by one, starting at the beginning. All |
| matching paths in the TNFA are traversed in parallel. When two or |
| more paths reach the same state, exactly one is chosen according to |
| tag ordering rules; if returning submatches is not required it does |
| not matter which path is chosen. |
| |
| The worst case time required for finding the leftmost and longest |
| match, or determining that there is no match, is always linearly |
| dependent on the length of the text being searched. |
| |
| This algorithm cannot handle TNFAs with back referencing nodes. |
| See `tre-match-backtrack.c'. |
| */ |
| |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif /* HAVE_CONFIG_H */ |
| |
| #ifdef TRE_USE_ALLOCA |
| /* AIX requires this to be the first thing in the file. */ |
| #ifndef __GNUC__ |
| # if HAVE_ALLOCA_H |
| # include <alloca.h> |
| # else |
| # ifdef _AIX |
| #pragma alloca |
| # else |
| # ifndef alloca /* predefined by HP cc +Olibcalls */ |
| char *alloca (); |
| # endif |
| # endif |
| # endif |
| #endif |
| #endif /* TRE_USE_ALLOCA */ |
| |
| // #include <assert.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #ifdef HAVE_WCHAR_H |
| #include <wchar.h> |
| #endif /* HAVE_WCHAR_H */ |
| #ifdef HAVE_WCTYPE_H |
| #include <wctype.h> |
| #endif /* HAVE_WCTYPE_H */ |
| #ifndef TRE_WCHAR |
| #include <ctype.h> |
| #endif /* !TRE_WCHAR */ |
| #ifdef HAVE_MALLOC_H |
| #include <malloc.h> |
| #endif /* HAVE_MALLOC_H */ |
| |
| #include "tre-internal.h" |
| #include "tre-match-utils.h" |
| #include "tre.h" |
| #include "xmalloc.h" |
| |
| #define assert(a) R_assert(a) |
| |
| typedef struct { |
| tre_tnfa_transition_t *state; |
| int *tags; |
| } tre_tnfa_reach_t; |
| |
| typedef struct { |
| int pos; |
| int **tags; |
| } tre_reach_pos_t; |
| |
| |
| #ifdef TRE_DEBUG |
| static void |
| tre_print_reach(const tre_tnfa_t *tnfa, tre_tnfa_reach_t *reach, int num_tags) |
| { |
| int i; |
| |
| while (reach->state != NULL) |
| { |
| DPRINT((" %p", (void *)reach->state)); |
| if (num_tags > 0) |
| { |
| DPRINT(("/")); |
| for (i = 0; i < num_tags; i++) |
| { |
| DPRINT(("%d:%d", i, reach->tags[i])); |
| if (i < (num_tags-1)) |
| DPRINT((",")); |
| } |
| } |
| reach++; |
| } |
| DPRINT(("\n")); |
| |
| } |
| #endif /* TRE_DEBUG */ |
| |
| reg_errcode_t |
| tre_tnfa_run_parallel(const tre_tnfa_t *tnfa, const void *string, int len, |
| tre_str_type_t type, int *match_tags, int eflags, |
| int *match_end_ofs) |
| { |
| /* State variables required by GET_NEXT_WCHAR. */ |
| tre_char_t prev_c = 0, next_c = 0; |
| const char *str_byte = string; |
| int pos = -1; |
| unsigned int pos_add_next = 1; |
| #ifdef TRE_WCHAR |
| const wchar_t *str_wide = string; |
| #ifdef TRE_MBSTATE |
| mbstate_t mbstate; |
| #endif /* TRE_MBSTATE */ |
| #endif /* TRE_WCHAR */ |
| int reg_notbol = eflags & REG_NOTBOL; |
| int reg_noteol = eflags & REG_NOTEOL; |
| int reg_newline = tnfa->cflags & REG_NEWLINE; |
| int str_user_end = 0; |
| |
| char *buf; |
| tre_tnfa_transition_t *trans_i; |
| tre_tnfa_reach_t *reach, *reach_next, *reach_i, *reach_next_i; |
| tre_reach_pos_t *reach_pos; |
| int *tag_i; |
| int num_tags, i; |
| |
| int match_eo = -1; /* end offset of match (-1 if no match found yet) */ |
| int new_match = 0; |
| int *tmp_tags = NULL; |
| int *tmp_iptr; |
| |
| #ifdef TRE_MBSTATE |
| memset(&mbstate, '\0', sizeof(mbstate)); |
| #endif /* TRE_MBSTATE */ |
| |
| DPRINT(("tre_tnfa_run_parallel, input type %d\n", type)); |
| |
| if (!match_tags) |
| num_tags = 0; |
| else |
| num_tags = tnfa->num_tags; |
| |
| /* Allocate memory for temporary data required for matching. This needs to |
| be done for every matching operation to be thread safe. This allocates |
| everything in a single large block from the stack frame using alloca() |
| or with malloc() if alloca is unavailable. */ |
| { |
| int tbytes, rbytes, pbytes, xbytes, total_bytes; |
| char *tmp_buf; |
| /* Compute the length of the block we need. */ |
| tbytes = sizeof(*tmp_tags) * num_tags; |
| rbytes = sizeof(*reach_next) * (tnfa->num_states + 1); |
| pbytes = sizeof(*reach_pos) * tnfa->num_states; |
| xbytes = sizeof(int) * num_tags; |
| total_bytes = |
| (sizeof(long) - 1) * 4 /* for alignment paddings */ |
| + (rbytes + xbytes * tnfa->num_states) * 2 + tbytes + pbytes; |
| |
| /* Allocate the memory. */ |
| #ifdef TRE_USE_ALLOCA |
| buf = alloca(total_bytes); |
| #else /* !TRE_USE_ALLOCA */ |
| buf = xmalloc((unsigned)total_bytes); |
| #endif /* !TRE_USE_ALLOCA */ |
| if (buf == NULL) |
| return REG_ESPACE; |
| memset(buf, 0, (size_t)total_bytes); |
| |
| /* Get the various pointers within tmp_buf (properly aligned). */ |
| tmp_tags = (void *)buf; |
| tmp_buf = buf + tbytes; |
| tmp_buf += ALIGN(tmp_buf, long); |
| reach_next = (void *)tmp_buf; |
| tmp_buf += rbytes; |
| tmp_buf += ALIGN(tmp_buf, long); |
| reach = (void *)tmp_buf; |
| tmp_buf += rbytes; |
| tmp_buf += ALIGN(tmp_buf, long); |
| reach_pos = (void *)tmp_buf; |
| tmp_buf += pbytes; |
| tmp_buf += ALIGN(tmp_buf, long); |
| for (i = 0; i < tnfa->num_states; i++) |
| { |
| reach[i].tags = (void *)tmp_buf; |
| tmp_buf += xbytes; |
| reach_next[i].tags = (void *)tmp_buf; |
| tmp_buf += xbytes; |
| } |
| } |
| |
| for (i = 0; i < tnfa->num_states; i++) |
| reach_pos[i].pos = -1; |
| |
| /* If only one character can start a match, find it first. */ |
| if (tnfa->first_char >= 0 && type == STR_BYTE && str_byte) |
| { |
| const char *orig_str = str_byte; |
| int first = tnfa->first_char; |
| |
| if (len >= 0) |
| str_byte = memchr(orig_str, first, (size_t)len); |
| else |
| str_byte = strchr(orig_str, first); |
| if (str_byte == NULL) |
| { |
| #ifndef TRE_USE_ALLOCA |
| if (buf) |
| xfree(buf); |
| #endif /* !TRE_USE_ALLOCA */ |
| return REG_NOMATCH; |
| } |
| DPRINT(("skipped %lu chars\n", (unsigned long)(str_byte - orig_str))); |
| if (str_byte >= orig_str + 1) |
| prev_c = (unsigned char)*(str_byte - 1); |
| next_c = (unsigned char)*str_byte; |
| pos = (int)(str_byte - orig_str); |
| if (len < 0 || pos < len) |
| str_byte++; |
| } |
| else |
| { |
| GET_NEXT_WCHAR(); |
| pos = 0; |
| } |
| |
| #if 0 |
| /* Skip over characters that cannot possibly be the first character |
| of a match. */ |
| if (tnfa->firstpos_chars != NULL) |
| { |
| char *chars = tnfa->firstpos_chars; |
| |
| if (len < 0) |
| { |
| const char *orig_str = str_byte; |
| /* XXX - use strpbrk() and wcspbrk() because they might be |
| optimized for the target architecture. Try also strcspn() |
| and wcscspn() and compare the speeds. */ |
| while (next_c != L'\0' && !chars[next_c]) |
| { |
| next_c = *str_byte++; |
| } |
| prev_c = *(str_byte - 2); |
| pos += str_byte - orig_str; |
| DPRINT(("skipped %d chars\n", str_byte - orig_str)); |
| } |
| else |
| { |
| while (pos <= len && !chars[next_c]) |
| { |
| prev_c = next_c; |
| next_c = (unsigned char)(*str_byte++); |
| pos++; |
| } |
| } |
| } |
| #endif |
| |
| DPRINT(("length: %d\n", len)); |
| DPRINT(("pos:chr/code | states and tags\n")); |
| DPRINT(("-------------+------------------------------------------------\n")); |
| |
| reach_next_i = reach_next; |
| while (/*CONSTCOND*/(void)1,1) |
| { |
| /* If no match found yet, add the initial states to `reach_next'. */ |
| if (match_eo < 0) |
| { |
| DPRINT((" init >")); |
| trans_i = tnfa->initial; |
| while (trans_i->state != NULL) |
| { |
| if (reach_pos[trans_i->state_id].pos < pos) |
| { |
| if (trans_i->assertions |
| && CHECK_ASSERTIONS(trans_i->assertions)) |
| { |
| DPRINT(("assertion failed\n")); |
| trans_i++; |
| continue; |
| } |
| |
| DPRINT((" %p", (void *)trans_i->state)); |
| reach_next_i->state = trans_i->state; |
| for (i = 0; i < num_tags; i++) |
| reach_next_i->tags[i] = -1; |
| tag_i = trans_i->tags; |
| if (tag_i) |
| while (*tag_i >= 0) |
| { |
| if (*tag_i < num_tags) |
| reach_next_i->tags[*tag_i] = pos; |
| tag_i++; |
| } |
| if (reach_next_i->state == tnfa->final) |
| { |
| DPRINT((" found empty match\n")); |
| match_eo = pos; |
| new_match = 1; |
| for (i = 0; i < num_tags; i++) |
| match_tags[i] = reach_next_i->tags[i]; |
| } |
| reach_pos[trans_i->state_id].pos = pos; |
| reach_pos[trans_i->state_id].tags = &reach_next_i->tags; |
| reach_next_i++; |
| } |
| trans_i++; |
| } |
| DPRINT(("\n")); |
| reach_next_i->state = NULL; |
| } |
| else |
| { |
| if (num_tags == 0 || reach_next_i == reach_next) |
| /* We have found a match. */ |
| break; |
| } |
| |
| /* Check for end of string. */ |
| if (len < 0) |
| { |
| if (type == STR_USER) |
| { |
| if (str_user_end) |
| break; |
| } |
| else if (next_c == L'\0') |
| break; |
| } |
| else |
| { |
| if (pos >= len) |
| break; |
| } |
| |
| GET_NEXT_WCHAR(); |
| |
| #ifdef TRE_DEBUG |
| DPRINT(("%3d:%2lc/%05d |", pos - 1, (tre_cint_t)prev_c, (int)prev_c)); |
| tre_print_reach(tnfa, reach_next, num_tags); |
| DPRINT(("%3d:%2lc/%05d |", pos, (tre_cint_t)next_c, (int)next_c)); |
| tre_print_reach(tnfa, reach_next, num_tags); |
| #endif /* TRE_DEBUG */ |
| |
| /* Swap `reach' and `reach_next'. */ |
| reach_i = reach; |
| reach = reach_next; |
| reach_next = reach_i; |
| |
| /* For each state in `reach', weed out states that don't fulfill the |
| minimal matching conditions. */ |
| if (tnfa->num_minimals && new_match) |
| { |
| new_match = 0; |
| reach_next_i = reach_next; |
| for (reach_i = reach; reach_i->state; reach_i++) |
| { |
| int skip = 0; |
| for (i = 0; tnfa->minimal_tags[i] >= 0; i += 2) |
| { |
| int end = tnfa->minimal_tags[i]; |
| int start = tnfa->minimal_tags[i + 1]; |
| DPRINT((" Minimal start %d, end %d\n", start, end)); |
| if (end >= num_tags) |
| { |
| DPRINT((" Throwing %p out.\n", reach_i->state)); |
| skip = 1; |
| break; |
| } |
| else if (reach_i->tags[start] == match_tags[start] |
| && reach_i->tags[end] < match_tags[end]) |
| { |
| DPRINT((" Throwing %p out because t%d < %d\n", |
| reach_i->state, end, match_tags[end])); |
| skip = 1; |
| break; |
| } |
| } |
| if (!skip) |
| { |
| reach_next_i->state = reach_i->state; |
| tmp_iptr = reach_next_i->tags; |
| reach_next_i->tags = reach_i->tags; |
| reach_i->tags = tmp_iptr; |
| reach_next_i++; |
| } |
| } |
| reach_next_i->state = NULL; |
| |
| /* Swap `reach' and `reach_next'. */ |
| reach_i = reach; |
| reach = reach_next; |
| reach_next = reach_i; |
| } |
| |
| /* For each state in `reach' see if there is a transition leaving with |
| the current input symbol to a state not yet in `reach_next', and |
| add the destination states to `reach_next'. */ |
| reach_next_i = reach_next; |
| for (reach_i = reach; reach_i->state; reach_i++) |
| { |
| for (trans_i = reach_i->state; trans_i->state; trans_i++) |
| { |
| /* Does this transition match the input symbol? */ |
| if (trans_i->code_min <= (tre_cint_t)prev_c && |
| trans_i->code_max >= (tre_cint_t)prev_c) |
| { |
| if (trans_i->assertions |
| && (CHECK_ASSERTIONS(trans_i->assertions) |
| || CHECK_CHAR_CLASSES(trans_i, tnfa, eflags))) |
| { |
| DPRINT(("assertion failed\n")); |
| continue; |
| } |
| |
| /* Compute the tags after this transition. */ |
| for (i = 0; i < num_tags; i++) |
| tmp_tags[i] = reach_i->tags[i]; |
| tag_i = trans_i->tags; |
| if (tag_i != NULL) |
| while (*tag_i >= 0) |
| { |
| if (*tag_i < num_tags) |
| tmp_tags[*tag_i] = pos; |
| tag_i++; |
| } |
| |
| if (reach_pos[trans_i->state_id].pos < pos) |
| { |
| /* Found an unvisited node. */ |
| reach_next_i->state = trans_i->state; |
| tmp_iptr = reach_next_i->tags; |
| reach_next_i->tags = tmp_tags; |
| tmp_tags = tmp_iptr; |
| reach_pos[trans_i->state_id].pos = pos; |
| reach_pos[trans_i->state_id].tags = &reach_next_i->tags; |
| |
| if (reach_next_i->state == tnfa->final |
| && (match_eo == -1 |
| || (num_tags > 0 |
| && reach_next_i->tags[0] <= match_tags[0]))) |
| { |
| DPRINT((" found match %p\n", trans_i->state)); |
| match_eo = pos; |
| new_match = 1; |
| for (i = 0; i < num_tags; i++) |
| match_tags[i] = reach_next_i->tags[i]; |
| } |
| reach_next_i++; |
| |
| } |
| else |
| { |
| assert(reach_pos[trans_i->state_id].pos == pos); |
| /* Another path has also reached this state. We choose |
| the winner by examining the tag values for both |
| paths. */ |
| if (tre_tag_order(num_tags, tnfa->tag_directions, |
| tmp_tags, |
| *reach_pos[trans_i->state_id].tags)) |
| { |
| /* The new path wins. */ |
| tmp_iptr = *reach_pos[trans_i->state_id].tags; |
| *reach_pos[trans_i->state_id].tags = tmp_tags; |
| if (trans_i->state == tnfa->final) |
| { |
| DPRINT((" found better match\n")); |
| match_eo = pos; |
| new_match = 1; |
| for (i = 0; i < num_tags; i++) |
| match_tags[i] = tmp_tags[i]; |
| } |
| tmp_tags = tmp_iptr; |
| } |
| } |
| } |
| } |
| } |
| reach_next_i->state = NULL; |
| } |
| |
| DPRINT(("match end offset = %d\n", match_eo)); |
| |
| #ifndef TRE_USE_ALLOCA |
| if (buf) |
| xfree(buf); |
| #endif /* !TRE_USE_ALLOCA */ |
| |
| *match_end_ofs = match_eo; |
| return match_eo >= 0 ? REG_OK : REG_NOMATCH; |
| } |
| |
| /* EOF */ |