The Squirrel interpreter. See http://www.squirrel-lang.org/
Diff: sqstdlib/sqstdrex.cpp
- Revision:
- 0:97a4f8cc534c
diff -r 000000000000 -r 97a4f8cc534c sqstdlib/sqstdrex.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/sqstdlib/sqstdrex.cpp Tue Dec 16 10:20:34 2014 +0000 @@ -0,0 +1,636 @@ +/* see copyright notice in squirrel.h */ +#include <squirrel.h> +#include <string.h> +#include <ctype.h> +#include <setjmp.h> +#include <sqstdstring.h> + +#ifdef _UINCODE +#define scisprint iswprint +#else +#define scisprint isprint +#endif + +#ifdef _DEBUG +#include <stdio.h> + +static const SQChar *g_nnames[] = +{ + _SC("NONE"),_SC("OP_GREEDY"), _SC("OP_OR"), + _SC("OP_EXPR"),_SC("OP_NOCAPEXPR"),_SC("OP_DOT"), _SC("OP_CLASS"), + _SC("OP_CCLASS"),_SC("OP_NCLASS"),_SC("OP_RANGE"),_SC("OP_CHAR"), + _SC("OP_EOL"),_SC("OP_BOL"),_SC("OP_WB") +}; + +#endif + +#define OP_GREEDY (MAX_CHAR+1) // * + ? {n} +#define OP_OR (MAX_CHAR+2) +#define OP_EXPR (MAX_CHAR+3) //parentesis () +#define OP_NOCAPEXPR (MAX_CHAR+4) //parentesis (?:) +#define OP_DOT (MAX_CHAR+5) +#define OP_CLASS (MAX_CHAR+6) +#define OP_CCLASS (MAX_CHAR+7) +#define OP_NCLASS (MAX_CHAR+8) //negates class the [^ +#define OP_RANGE (MAX_CHAR+9) +#define OP_CHAR (MAX_CHAR+10) +#define OP_EOL (MAX_CHAR+11) +#define OP_BOL (MAX_CHAR+12) +#define OP_WB (MAX_CHAR+13) + +#define SQREX_SYMBOL_ANY_CHAR ('.') +#define SQREX_SYMBOL_GREEDY_ONE_OR_MORE ('+') +#define SQREX_SYMBOL_GREEDY_ZERO_OR_MORE ('*') +#define SQREX_SYMBOL_GREEDY_ZERO_OR_ONE ('?') +#define SQREX_SYMBOL_BRANCH ('|') +#define SQREX_SYMBOL_END_OF_STRING ('$') +#define SQREX_SYMBOL_BEGINNING_OF_STRING ('^') +#define SQREX_SYMBOL_ESCAPE_CHAR ('\\') + + +typedef int SQRexNodeType; + +typedef struct tagSQRexNode{ + SQRexNodeType type; + SQInteger left; + SQInteger right; + SQInteger next; +}SQRexNode; + +struct SQRex{ + const SQChar *_eol; + const SQChar *_bol; + const SQChar *_p; + SQInteger _first; + SQInteger _op; + SQRexNode *_nodes; + SQInteger _nallocated; + SQInteger _nsize; + SQInteger _nsubexpr; + SQRexMatch *_matches; + SQInteger _currsubexp; + void *_jmpbuf; + const SQChar **_error; +}; + +static SQInteger sqstd_rex_list(SQRex *exp); + +static SQInteger sqstd_rex_newnode(SQRex *exp, SQRexNodeType type) +{ + SQRexNode n; + n.type = type; + n.next = n.right = n.left = -1; + if(type == OP_EXPR) + n.right = exp->_nsubexpr++; + if(exp->_nallocated < (exp->_nsize + 1)) { + SQInteger oldsize = exp->_nallocated; + exp->_nallocated *= 2; + exp->_nodes = (SQRexNode *)sq_realloc(exp->_nodes, oldsize * sizeof(SQRexNode) ,exp->_nallocated * sizeof(SQRexNode)); + } + exp->_nodes[exp->_nsize++] = n; + SQInteger newid = exp->_nsize - 1; + return (SQInteger)newid; +} + +static void sqstd_rex_error(SQRex *exp,const SQChar *error) +{ + if(exp->_error) *exp->_error = error; + longjmp(*((jmp_buf*)exp->_jmpbuf),-1); +} + +static void sqstd_rex_expect(SQRex *exp, SQInteger n){ + if((*exp->_p) != n) + sqstd_rex_error(exp, _SC("expected paren")); + exp->_p++; +} + +static SQChar sqstd_rex_escapechar(SQRex *exp) +{ + if(*exp->_p == SQREX_SYMBOL_ESCAPE_CHAR){ + exp->_p++; + switch(*exp->_p) { + case 'v': exp->_p++; return '\v'; + case 'n': exp->_p++; return '\n'; + case 't': exp->_p++; return '\t'; + case 'r': exp->_p++; return '\r'; + case 'f': exp->_p++; return '\f'; + default: return (*exp->_p++); + } + } else if(!scisprint(*exp->_p)) sqstd_rex_error(exp,_SC("letter expected")); + return (*exp->_p++); +} + +static SQInteger sqstd_rex_charclass(SQRex *exp,SQInteger classid) +{ + SQInteger n = sqstd_rex_newnode(exp,OP_CCLASS); + exp->_nodes[n].left = classid; + return n; +} + +static SQInteger sqstd_rex_charnode(SQRex *exp,SQBool isclass) +{ + SQChar t; + if(*exp->_p == SQREX_SYMBOL_ESCAPE_CHAR) { + exp->_p++; + switch(*exp->_p) { + case 'n': exp->_p++; return sqstd_rex_newnode(exp,'\n'); + case 't': exp->_p++; return sqstd_rex_newnode(exp,'\t'); + case 'r': exp->_p++; return sqstd_rex_newnode(exp,'\r'); + case 'f': exp->_p++; return sqstd_rex_newnode(exp,'\f'); + case 'v': exp->_p++; return sqstd_rex_newnode(exp,'\v'); + case 'a': case 'A': case 'w': case 'W': case 's': case 'S': + case 'd': case 'D': case 'x': case 'X': case 'c': case 'C': + case 'p': case 'P': case 'l': case 'u': + { + t = *exp->_p; exp->_p++; + return sqstd_rex_charclass(exp,t); + } + case 'b': + case 'B': + if(!isclass) { + SQInteger node = sqstd_rex_newnode(exp,OP_WB); + exp->_nodes[node].left = *exp->_p; + exp->_p++; + return node; + } //else default + default: + t = *exp->_p; exp->_p++; + return sqstd_rex_newnode(exp,t); + } + } + else if(!scisprint(*exp->_p)) { + + sqstd_rex_error(exp,_SC("letter expected")); + } + t = *exp->_p; exp->_p++; + return sqstd_rex_newnode(exp,t); +} +static SQInteger sqstd_rex_class(SQRex *exp) +{ + SQInteger ret = -1; + SQInteger first = -1,chain; + if(*exp->_p == SQREX_SYMBOL_BEGINNING_OF_STRING){ + ret = sqstd_rex_newnode(exp,OP_NCLASS); + exp->_p++; + }else ret = sqstd_rex_newnode(exp,OP_CLASS); + + if(*exp->_p == ']') sqstd_rex_error(exp,_SC("empty class")); + chain = ret; + while(*exp->_p != ']' && exp->_p != exp->_eol) { + if(*exp->_p == '-' && first != -1){ + SQInteger r; + if(*exp->_p++ == ']') sqstd_rex_error(exp,_SC("unfinished range")); + r = sqstd_rex_newnode(exp,OP_RANGE); + if(exp->_nodes[first].type>*exp->_p) sqstd_rex_error(exp,_SC("invalid range")); + if(exp->_nodes[first].type == OP_CCLASS) sqstd_rex_error(exp,_SC("cannot use character classes in ranges")); + exp->_nodes[r].left = exp->_nodes[first].type; + SQInteger t = sqstd_rex_escapechar(exp); + exp->_nodes[r].right = t; + exp->_nodes[chain].next = r; + chain = r; + first = -1; + } + else{ + if(first!=-1){ + SQInteger c = first; + exp->_nodes[chain].next = c; + chain = c; + first = sqstd_rex_charnode(exp,SQTrue); + } + else{ + first = sqstd_rex_charnode(exp,SQTrue); + } + } + } + if(first!=-1){ + SQInteger c = first; + exp->_nodes[chain].next = c; + chain = c; + first = -1; + } + /* hack? */ + exp->_nodes[ret].left = exp->_nodes[ret].next; + exp->_nodes[ret].next = -1; + return ret; +} + +static SQInteger sqstd_rex_parsenumber(SQRex *exp) +{ + SQInteger ret = *exp->_p-'0'; + SQInteger positions = 10; + exp->_p++; + while(isdigit(*exp->_p)) { + ret = ret*10+(*exp->_p++-'0'); + if(positions==1000000000) sqstd_rex_error(exp,_SC("overflow in numeric constant")); + positions *= 10; + }; + return ret; +} + +static SQInteger sqstd_rex_element(SQRex *exp) +{ + SQInteger ret = -1; + switch(*exp->_p) + { + case '(': { + SQInteger expr; + exp->_p++; + + + if(*exp->_p =='?') { + exp->_p++; + sqstd_rex_expect(exp,':'); + expr = sqstd_rex_newnode(exp,OP_NOCAPEXPR); + } + else + expr = sqstd_rex_newnode(exp,OP_EXPR); + SQInteger newn = sqstd_rex_list(exp); + exp->_nodes[expr].left = newn; + ret = expr; + sqstd_rex_expect(exp,')'); + } + break; + case '[': + exp->_p++; + ret = sqstd_rex_class(exp); + sqstd_rex_expect(exp,']'); + break; + case SQREX_SYMBOL_END_OF_STRING: exp->_p++; ret = sqstd_rex_newnode(exp,OP_EOL);break; + case SQREX_SYMBOL_ANY_CHAR: exp->_p++; ret = sqstd_rex_newnode(exp,OP_DOT);break; + default: + ret = sqstd_rex_charnode(exp,SQFalse); + break; + } + + + SQBool isgreedy = SQFalse; + unsigned short p0 = 0, p1 = 0; + switch(*exp->_p){ + case SQREX_SYMBOL_GREEDY_ZERO_OR_MORE: p0 = 0; p1 = 0xFFFF; exp->_p++; isgreedy = SQTrue; break; + case SQREX_SYMBOL_GREEDY_ONE_OR_MORE: p0 = 1; p1 = 0xFFFF; exp->_p++; isgreedy = SQTrue; break; + case SQREX_SYMBOL_GREEDY_ZERO_OR_ONE: p0 = 0; p1 = 1; exp->_p++; isgreedy = SQTrue; break; + case '{': + exp->_p++; + if(!isdigit(*exp->_p)) sqstd_rex_error(exp,_SC("number expected")); + p0 = (unsigned short)sqstd_rex_parsenumber(exp); + /*******************************/ + switch(*exp->_p) { + case '}': + p1 = p0; exp->_p++; + break; + case ',': + exp->_p++; + p1 = 0xFFFF; + if(isdigit(*exp->_p)){ + p1 = (unsigned short)sqstd_rex_parsenumber(exp); + } + sqstd_rex_expect(exp,'}'); + break; + default: + sqstd_rex_error(exp,_SC(", or } expected")); + } + /*******************************/ + isgreedy = SQTrue; + break; + + } + if(isgreedy) { + SQInteger nnode = sqstd_rex_newnode(exp,OP_GREEDY); + exp->_nodes[nnode].left = ret; + exp->_nodes[nnode].right = ((p0)<<16)|p1; + ret = nnode; + } + + if((*exp->_p != SQREX_SYMBOL_BRANCH) && (*exp->_p != ')') && (*exp->_p != SQREX_SYMBOL_GREEDY_ZERO_OR_MORE) && (*exp->_p != SQREX_SYMBOL_GREEDY_ONE_OR_MORE) && (*exp->_p != '\0')) { + SQInteger nnode = sqstd_rex_element(exp); + exp->_nodes[ret].next = nnode; + } + + return ret; +} + +static SQInteger sqstd_rex_list(SQRex *exp) +{ + SQInteger ret=-1,e; + if(*exp->_p == SQREX_SYMBOL_BEGINNING_OF_STRING) { + exp->_p++; + ret = sqstd_rex_newnode(exp,OP_BOL); + } + e = sqstd_rex_element(exp); + if(ret != -1) { + exp->_nodes[ret].next = e; + } + else ret = e; + + if(*exp->_p == SQREX_SYMBOL_BRANCH) { + SQInteger temp,tright; + exp->_p++; + temp = sqstd_rex_newnode(exp,OP_OR); + exp->_nodes[temp].left = ret; + tright = sqstd_rex_list(exp); + exp->_nodes[temp].right = tright; + ret = temp; + } + return ret; +} + +static SQBool sqstd_rex_matchcclass(SQInteger cclass,SQChar c) +{ + switch(cclass) { + case 'a': return isalpha(c)?SQTrue:SQFalse; + case 'A': return !isalpha(c)?SQTrue:SQFalse; + case 'w': return (isalnum(c) || c == '_')?SQTrue:SQFalse; + case 'W': return (!isalnum(c) && c != '_')?SQTrue:SQFalse; + case 's': return isspace(c)?SQTrue:SQFalse; + case 'S': return !isspace(c)?SQTrue:SQFalse; + case 'd': return isdigit(c)?SQTrue:SQFalse; + case 'D': return !isdigit(c)?SQTrue:SQFalse; + case 'x': return isxdigit(c)?SQTrue:SQFalse; + case 'X': return !isxdigit(c)?SQTrue:SQFalse; + case 'c': return iscntrl(c)?SQTrue:SQFalse; + case 'C': return !iscntrl(c)?SQTrue:SQFalse; + case 'p': return ispunct(c)?SQTrue:SQFalse; + case 'P': return !ispunct(c)?SQTrue:SQFalse; + case 'l': return islower(c)?SQTrue:SQFalse; + case 'u': return isupper(c)?SQTrue:SQFalse; + } + return SQFalse; /*cannot happen*/ +} + +static SQBool sqstd_rex_matchclass(SQRex* exp,SQRexNode *node,SQChar c) +{ + do { + switch(node->type) { + case OP_RANGE: + if(c >= node->left && c <= node->right) return SQTrue; + break; + case OP_CCLASS: + if(sqstd_rex_matchcclass(node->left,c)) return SQTrue; + break; + default: + if(c == node->type)return SQTrue; + } + } while((node->next != -1) && (node = &exp->_nodes[node->next])); + return SQFalse; +} + +static const SQChar *sqstd_rex_matchnode(SQRex* exp,SQRexNode *node,const SQChar *str,SQRexNode *next) +{ + + SQRexNodeType type = node->type; + switch(type) { + case OP_GREEDY: { + //SQRexNode *greedystop = (node->next != -1) ? &exp->_nodes[node->next] : NULL; + SQRexNode *greedystop = NULL; + SQInteger p0 = (node->right >> 16)&0x0000FFFF, p1 = node->right&0x0000FFFF, nmaches = 0; + const SQChar *s=str, *good = str; + + if(node->next != -1) { + greedystop = &exp->_nodes[node->next]; + } + else { + greedystop = next; + } + + while((nmaches == 0xFFFF || nmaches < p1)) { + + const SQChar *stop; + if(!(s = sqstd_rex_matchnode(exp,&exp->_nodes[node->left],s,greedystop))) + break; + nmaches++; + good=s; + if(greedystop) { + //checks that 0 matches satisfy the expression(if so skips) + //if not would always stop(for instance if is a '?') + if(greedystop->type != OP_GREEDY || + (greedystop->type == OP_GREEDY && ((greedystop->right >> 16)&0x0000FFFF) != 0)) + { + SQRexNode *gnext = NULL; + if(greedystop->next != -1) { + gnext = &exp->_nodes[greedystop->next]; + }else if(next && next->next != -1){ + gnext = &exp->_nodes[next->next]; + } + stop = sqstd_rex_matchnode(exp,greedystop,s,gnext); + if(stop) { + //if satisfied stop it + if(p0 == p1 && p0 == nmaches) break; + else if(nmaches >= p0 && p1 == 0xFFFF) break; + else if(nmaches >= p0 && nmaches <= p1) break; + } + } + } + + if(s >= exp->_eol) + break; + } + if(p0 == p1 && p0 == nmaches) return good; + else if(nmaches >= p0 && p1 == 0xFFFF) return good; + else if(nmaches >= p0 && nmaches <= p1) return good; + return NULL; + } + case OP_OR: { + const SQChar *asd = str; + SQRexNode *temp=&exp->_nodes[node->left]; + while( (asd = sqstd_rex_matchnode(exp,temp,asd,NULL)) ) { + if(temp->next != -1) + temp = &exp->_nodes[temp->next]; + else + return asd; + } + asd = str; + temp = &exp->_nodes[node->right]; + while( (asd = sqstd_rex_matchnode(exp,temp,asd,NULL)) ) { + if(temp->next != -1) + temp = &exp->_nodes[temp->next]; + else + return asd; + } + return NULL; + break; + } + case OP_EXPR: + case OP_NOCAPEXPR:{ + SQRexNode *n = &exp->_nodes[node->left]; + const SQChar *cur = str; + SQInteger capture = -1; + if(node->type != OP_NOCAPEXPR && node->right == exp->_currsubexp) { + capture = exp->_currsubexp; + exp->_matches[capture].begin = cur; + exp->_currsubexp++; + } + int tempcap = exp->_currsubexp; + do { + SQRexNode *subnext = NULL; + if(n->next != -1) { + subnext = &exp->_nodes[n->next]; + }else { + subnext = next; + } + if(!(cur = sqstd_rex_matchnode(exp,n,cur,subnext))) { + if(capture != -1){ + exp->_matches[capture].begin = 0; + exp->_matches[capture].len = 0; + } + return NULL; + } + } while((n->next != -1) && (n = &exp->_nodes[n->next])); + + exp->_currsubexp = tempcap; + if(capture != -1) + exp->_matches[capture].len = cur - exp->_matches[capture].begin; + return cur; + } + case OP_WB: + if((str == exp->_bol && !isspace(*str)) + || (str == exp->_eol && !isspace(*(str-1))) + || (!isspace(*str) && isspace(*(str+1))) + || (isspace(*str) && !isspace(*(str+1))) ) { + return (node->left == 'b')?str:NULL; + } + return (node->left == 'b')?NULL:str; + case OP_BOL: + if(str == exp->_bol) return str; + return NULL; + case OP_EOL: + if(str == exp->_eol) return str; + return NULL; + case OP_DOT:{ + str++; + } + return str; + case OP_NCLASS: + case OP_CLASS: + if(sqstd_rex_matchclass(exp,&exp->_nodes[node->left],*str)?(type == OP_CLASS?SQTrue:SQFalse):(type == OP_NCLASS?SQTrue:SQFalse)) { + str++; + return str; + } + return NULL; + case OP_CCLASS: + if(sqstd_rex_matchcclass(node->left,*str)) { + str++; + return str; + } + return NULL; + default: /* char */ + if(*str != node->type) return NULL; + str++; + return str; + } + return NULL; +} + +/* public api */ +SQRex *sqstd_rex_compile(const SQChar *pattern,const SQChar **error) +{ + SQRex *exp = (SQRex *)sq_malloc(sizeof(SQRex)); + exp->_eol = exp->_bol = NULL; + exp->_p = pattern; + exp->_nallocated = (SQInteger)scstrlen(pattern) * sizeof(SQChar); + exp->_nodes = (SQRexNode *)sq_malloc(exp->_nallocated * sizeof(SQRexNode)); + exp->_nsize = 0; + exp->_matches = 0; + exp->_nsubexpr = 0; + exp->_first = sqstd_rex_newnode(exp,OP_EXPR); + exp->_error = error; + exp->_jmpbuf = sq_malloc(sizeof(jmp_buf)); + if(setjmp(*((jmp_buf*)exp->_jmpbuf)) == 0) { + SQInteger res = sqstd_rex_list(exp); + exp->_nodes[exp->_first].left = res; + if(*exp->_p!='\0') + sqstd_rex_error(exp,_SC("unexpected character")); +#ifdef _DEBUG + { + SQInteger nsize,i; + SQRexNode *t; + nsize = exp->_nsize; + t = &exp->_nodes[0]; + scprintf(_SC("\n")); + for(i = 0;i < nsize; i++) { + if(exp->_nodes[i].type>MAX_CHAR) + scprintf(_SC("[%02d] %10s "),i,g_nnames[exp->_nodes[i].type-MAX_CHAR]); + else + scprintf(_SC("[%02d] %10c "),i,exp->_nodes[i].type); + scprintf(_SC("left %02d right %02d next %02d\n"),exp->_nodes[i].left,exp->_nodes[i].right,exp->_nodes[i].next); + } + scprintf(_SC("\n")); + } +#endif + exp->_matches = (SQRexMatch *) sq_malloc(exp->_nsubexpr * sizeof(SQRexMatch)); + memset(exp->_matches,0,exp->_nsubexpr * sizeof(SQRexMatch)); + } + else{ + sqstd_rex_free(exp); + return NULL; + } + return exp; +} + +void sqstd_rex_free(SQRex *exp) +{ + if(exp) { + if(exp->_nodes) sq_free(exp->_nodes,exp->_nallocated * sizeof(SQRexNode)); + if(exp->_jmpbuf) sq_free(exp->_jmpbuf,sizeof(jmp_buf)); + if(exp->_matches) sq_free(exp->_matches,exp->_nsubexpr * sizeof(SQRexMatch)); + sq_free(exp,sizeof(SQRex)); + } +} + +SQBool sqstd_rex_match(SQRex* exp,const SQChar* text) +{ + const SQChar* res = NULL; + exp->_bol = text; + exp->_eol = text + scstrlen(text); + exp->_currsubexp = 0; + res = sqstd_rex_matchnode(exp,exp->_nodes,text,NULL); + if(res == NULL || res != exp->_eol) + return SQFalse; + return SQTrue; +} + +SQBool sqstd_rex_searchrange(SQRex* exp,const SQChar* text_begin,const SQChar* text_end,const SQChar** out_begin, const SQChar** out_end) +{ + const SQChar *cur = NULL; + SQInteger node = exp->_first; + if(text_begin >= text_end) return SQFalse; + exp->_bol = text_begin; + exp->_eol = text_end; + do { + cur = text_begin; + while(node != -1) { + exp->_currsubexp = 0; + cur = sqstd_rex_matchnode(exp,&exp->_nodes[node],cur,NULL); + if(!cur) + break; + node = exp->_nodes[node].next; + } + text_begin++; + } while(cur == NULL && text_begin != text_end); + + if(cur == NULL) + return SQFalse; + + --text_begin; + + if(out_begin) *out_begin = text_begin; + if(out_end) *out_end = cur; + return SQTrue; +} + +SQBool sqstd_rex_search(SQRex* exp,const SQChar* text, const SQChar** out_begin, const SQChar** out_end) +{ + return sqstd_rex_searchrange(exp,text,text + scstrlen(text),out_begin,out_end); +} + +SQInteger sqstd_rex_getsubexpcount(SQRex* exp) +{ + return exp->_nsubexpr; +} + +SQBool sqstd_rex_getsubexp(SQRex* exp, SQInteger n, SQRexMatch *subexp) +{ + if( n<0 || n >= exp->_nsubexpr) return SQFalse; + *subexp = exp->_matches[n]; + return SQTrue; +} +