/* * ngIRCd -- The Next Generation IRC Daemon * Copyright (c)2001,2002 by Alexander Barton (alex@barton.de) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * Please read the file COPYING, README and AUTHORS for more information. * * Wildcard pattern matching */ #include "portab.h" static char UNUSED id[] = "$Id: match.c,v 1.2 2002/12/12 12:24:18 alex Exp $"; #include "imp.h" #include #include #include "exp.h" #include "match.h" /* * Die Pattern-Matching-Funkionen [Matche(), Matche_After_Star()] basieren * auf Versionen von J. Kercheval. Die Version 1.1 wurde am 12.03.1991 als * "public domain" freigegeben: * */ LOCAL INT Matche PARAMS(( REGISTER CHAR *p, REGISTER CHAR *t )); LOCAL INT Matche_After_Star PARAMS(( REGISTER CHAR *p, REGISTER CHAR *t )); #define MATCH_PATTERN 6 /* bad pattern */ #define MATCH_LITERAL 5 /* match failure on literal match */ #define MATCH_RANGE 4 /* match failure on [..] construct */ #define MATCH_ABORT 3 /* premature end of text string */ #define MATCH_END 2 /* premature end of pattern string */ #define MATCH_VALID 1 /* valid match */ GLOBAL BOOLEAN Match( CHAR *Pattern, CHAR *String ) { /* Pattern mit String vergleichen */ if( Matche( Pattern, String ) == MATCH_VALID ) return TRUE; else return FALSE; } /* Match */ LOCAL INT Matche( REGISTER CHAR *p, REGISTER CHAR *t ) { REGISTER CHAR range_start, range_end; BOOLEAN invert; BOOLEAN member_match; BOOLEAN loop; for( ; *p; p++, t++ ) { /* if this is the end of the text then this is the end of the match */ if( ! *t ) { return ( *p == '*' && *++p == '\0' ) ? MATCH_VALID : MATCH_ABORT; } /* determine and react to pattern type */ switch( *p ) { case '?': /* single any character match */ break; case '*': /* multiple any character match */ return Matche_After_Star( p, t ); case '[': /* [..] construct, single member/exclusion character match */ /* move to beginning of range */ p++; /* check if this is a member match or exclusion match */ invert = FALSE; if( *p == '!' || *p == '^' ) { invert = TRUE; p++; } /* if closing bracket here or at range start then we have a malformed pattern */ if ( *p == ']' ) return MATCH_PATTERN; member_match = FALSE; loop = TRUE; while( loop ) { /* if end of construct then loop is done */ if( *p == ']' ) { loop = FALSE; continue; } /* matching a '!', '^', '-', '\' or a ']' */ if( *p == '\\' ) range_start = range_end = *++p; else range_start = range_end = *p; /* if end of pattern then bad pattern (Missing ']') */ if( ! *p ) return MATCH_PATTERN; /* check for range bar */ if( *++p == '-' ) { /* get the range end */ range_end = *++p; /* if end of pattern or construct then bad pattern */ if( range_end == '\0' || range_end == ']' ) return MATCH_PATTERN; /* special character range end */ if( range_end == '\\' ) { range_end = *++p; /* if end of text then we have a bad pattern */ if ( ! range_end ) return MATCH_PATTERN; } /* move just beyond this range */ p++; } /* if the text character is in range then match found. make sure the range * letters have the proper relationship to one another before comparison */ if( range_start < range_end ) { if( *t >= range_start && *t <= range_end ) { member_match = TRUE; loop = FALSE; } } else { if( *t >= range_end && *t <= range_start ) { member_match = TRUE; loop = FALSE; } } } /* if there was a match in an exclusion set then no match */ /* if there was no match in a member set then no match */ if(( invert && member_match ) || ! ( invert || member_match )) return MATCH_RANGE; /* if this is not an exclusion then skip the rest of the [...] * construct that already matched. */ if( member_match ) { while( *p != ']' ) { /* bad pattern (Missing ']') */ if( ! *p ) return MATCH_PATTERN; /* skip exact match */ if( *p == '\\' ) { p++; /* if end of text then we have a bad pattern */ if( ! *p ) return MATCH_PATTERN; } /* move to next pattern char */ p++; } } break; case '\\': /* next character is quoted and must match exactly */ /* move pattern pointer to quoted char and fall through */ p++; /* if end of text then we have a bad pattern */ if( ! *p ) return MATCH_PATTERN; /* must match this character exactly */ default: if( *p != *t ) return MATCH_LITERAL; } } /* if end of text not reached then the pattern fails */ if( *t ) return MATCH_END; else return MATCH_VALID; } /* Matche */ LOCAL INT Matche_After_Star( REGISTER CHAR *p, REGISTER CHAR *t ) { REGISTER INT nextp, match = 0; /* pass over existing ? and * in pattern */ while( *p == '?' || *p == '*' ) { /* take one char for each ? and + */ if (*p == '?') { /* if end of text then no match */ if( ! *t++ ) return MATCH_ABORT; } /* move to next char in pattern */ p++; } /* if end of pattern we have matched regardless of text left */ if( ! *p ) return MATCH_VALID; /* get the next character to match which must be a literal or '[' */ nextp = *p; if( nextp == '\\' ) { nextp = p[1]; /* if end of text then we have a bad pattern */ if( ! nextp ) return MATCH_PATTERN; } /* Continue until we run out of text or definite result seen */ do { /* a precondition for matching is that the next character * in the pattern match the next character in the text or that * the next pattern char is the beginning of a range. Increment * text pointer as we go here */ if( nextp == *t || nextp == '[' ) match = Matche( p, t ); /* if the end of text is reached then no match */ if( ! *t++ ) match = MATCH_ABORT; } while( match != MATCH_VALID && match != MATCH_ABORT && match != MATCH_PATTERN ); /* return result */ return match; } /* Matche_After_Star */ /* -eof- */