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Path: seismo!uunet!rs From: rs@uunet.UU.NET (Rich Salz) Newsgroups: comp.sources.unix Subject: v09i062: Fastest grep around, Part02/02 Message-ID: <366@uunet.UU.NET> Date: 16 Jun 87 23:37:04 GMT Organization: UUNET Communications Services, Arlington, VA Lines: 2231 Approved: rs@uunet.uu.net Submitted by: James A. Woods <ames!aurora!jaw> Mod.sources: Volume 9, Issue 62 Archive-name: fastgrep/Part02 [ This was previously published in mod.sources, but was part of James's distribution and contains a bugfix mailed to me by Henry Spencer. (Giving proper credit, the bug was found by Jeff McCarrell at Berkeley.) The bug was in the NEXT macro, line 116 of regexp.c --r$ ] # To unbundle, sh this file echo README.regexp 1>&2 cat > README.regexp <<'End of README.regexp' This is a nearly-public-domain reimplementation of the V8 regexp(3) package. It gives C programs the ability to use egrep-style regular expressions, and does it in a much cleaner fashion than the analogous routines in SysV. Copyright (c) 1986 by University of Toronto. Written by Henry Spencer. Not derived from licensed software. Permission is granted to anyone to use this software for any purpose on any computer system, and to redistribute it freely, subject to the following restrictions: 1. The author is not responsible for the consequences of use of this software, no matter how awful, even if they arise from defects in it. 2. The origin of this software must not be misrepresented, either by explicit claim or by omission. 3. Altered versions must be plainly marked as such, and must not be misrepresented as being the original software. Barring a couple of small items in the BUGS list, this implementation is believed 100% compatible with V8. It should even be binary-compatible, sort of, since the only fields in a "struct regexp" that other people have any business touching are declared in exactly the same way at the same location in the struct (the beginning). This implementation is *NOT* AT&T/Bell code, and is not derived from licensed software. Even though U of T is a V8 licensee. This software is based on a V8 manual page sent to me by Dennis Ritchie (the manual page enclosed here is a complete rewrite and hence is not covered by AT&T copyright). The software was nearly complete at the time of arrival of our V8 tape. I haven't even looked at V8 yet, although a friend elsewhere at U of T has been kind enough to run a few test programs using the V8 regexp(3) to resolve a few fine points. I admit to some familiarity with regular-expression implementations of the past, but the only one that this code traces any ancestry to is the one published in Kernighan & Plauger (from which this one draws ideas but not code). Simplistically: put this stuff into a source directory, copy regexp.h into /usr/include, inspect Makefile for compilation options that need changing to suit your local environment, and then do "make r". This compiles the regexp(3) functions, compiles a test program, and runs a large set of regression tests. If there are no complaints, then put regexp.o, regsub.o, and regerror.o into your C library, and regexp.3 into your manual-pages directory. Note that if you don't put regexp.h into /usr/include *before* compiling, you'll have to add "-I." to CFLAGS before compiling. The files are: Makefile instructions to make everything regexp.3 manual page regexp.h header file, for /usr/include regexp.c source for regcomp() and regexec() regsub.c source for regsub() regerror.c source for default regerror() regmagic.h internal header file try.c source for test program timer.c source for timing program tests test list for try and timer This implementation uses nondeterministic automata rather than the deterministic ones found in some other implementations, which makes it simpler, smaller, and faster at compiling regular expressions, but slower at executing them. In theory, anyway. This implementation does employ some special-case optimizations to make the simpler cases (which do make up the bulk of regular expressions actually used) run quickly. In general, if you want blazing speed you're in the wrong place. Replacing the insides of egrep with this stuff is probably a mistake; if you want your own egrep you're going to have to do a lot more work. But if you want to use regular expressions a little bit in something else, you're in luck. Note that many existing text editors use nondeterministic regular-expression implementations, so you're in good company. This stuff should be pretty portable, given appropriate option settings. If your chars have less than 8 bits, you're going to have to change the internal representation of the automaton, although knowledge of the details of this is fairly localized. There are no "reserved" char values except for NUL, and no special significance is attached to the top bit of chars. The string(3) functions are used a fair bit, on the grounds that they are probably faster than coding the operations in line. Some attempts at code tuning have been made, but this is invariably a bit machine-specific. End of README.regexp echo Makefile.regexp 1>&2 cat > Makefile.regexp <<'End of Makefile.regexp' # Things you might want to put in ENV and LENV: # -Dvoid=int compilers that don't do void # -DCHARBITS=0377 compilers that don't do unsigned char # -DSTATIC=extern compilers that don't like "static foo();" as forward decl # -DSTRCSPN library does not have strcspn() # -Dstrchr=index library does not have strchr() # -DERRAVAIL have utzoo-compatible error() function and friends ENV= LENV= # Things you might want to put in TEST: # -DDEBUG debugging hooks # -I. regexp.h from current directory, not /usr/include TEST= -I. # Things you might want to put in PROF: # -Dstatic='/* */' make everything global so profiler can see it. # -p profiler PROF= CFLAGS=-O $(ENV) $(TEST) $(PROF) LINTFLAGS=$(LENV) $(TEST) -ha #LDFLAGS=-i uncomment for pdp 11 OBJ=regexp.o regsub.o LSRC=regexp.c regsub.c regerror.c DTR=README.regexp dMakefile regexp.3 regexp.h regexp.c regsub.c regerror.c \ regmagic.h try.c timer.c tests try: try.o $(OBJ) cc $(LDFLAGS) try.o $(OBJ) -o try # Making timer will probably require putting stuff in $(PROF) and then # recompiling everything; the following is just the final stage. timer: timer.o $(OBJ) cc $(LDFLAGS) $(PROF) timer.o $(OBJ) -o timer timer.o: timer.c timer.t.h timer.t.h: tests sed 's/ /","/g;s/\\/&&/g;s/.*/{"&"},/' tests >timer.t.h # Regression test. r: try tests @echo 'No news is good news...' try <tests lint: timer.t.h @echo 'Complaints about multiply-declared regerror() are legit.' lint $(LINTFLAGS) $(LSRC) try.c lint $(LINTFLAGS) $(LSRC) timer.c regexp.o: regexp.c regexp.h regmagic.h regsub.o: regsub.c regexp.h regmagic.h clean: rm -f *.o core mon.out timer.t.h dMakefile dtr try timer dtr: r makedtr $(DTR) makedtr $(DTR) >dtr dMakefile: Makefile sed '/^L*ENV=/s/ *-DERRAVAIL//' Makefile >dMakefile End of Makefile.regexp echo regexp.3 1>&2 cat > regexp.3 <<'End of regexp.3' .TH REGEXP 3 local .DA 30 Nov 1985 .SH NAME regcomp, regexec, regsub, regerror \- regular expression handler .SH SYNOPSIS .ft B .nf #include <regexp.h> regexp *regcomp(exp) char *exp; int regexec(prog, string) regexp *prog; char *string; regsub(prog, source, dest) regexp *prog; char *source; char *dest; regerror(msg) char *msg; .SH DESCRIPTION These functions implement .IR egrep (1)-style regular expressions and supporting facilities. .PP .I Regcomp compiles a regular expression into a structure of type .IR regexp , and returns a pointer to it. The space has been allocated using .IR malloc (3) and may be released by .IR free . .PP .I Regexec matches a NUL-terminated \fIstring\fR against the compiled regular expression in \fIprog\fR. It returns 1 for success and 0 for failure, and adjusts the contents of \fIprog\fR's \fIstartp\fR and \fIendp\fR (see below) accordingly. .PP The members of a .I regexp structure include at least the following (not necessarily in order): .PP .RS char *startp[NSUBEXP]; .br char *endp[NSUBEXP]; .RE .PP where .I NSUBEXP is defined (as 10) in the header file. Once a successful \fIregexec\fR has been done using the \fIregexp\fR, each \fIstartp\fR-\fIendp\fR pair describes one substring within the \fIstring\fR, with the \fIstartp\fR pointing to the first character of the substring and the \fIendp\fR pointing to the first character following the substring. The 0th substring is the substring of \fIstring\fR that matched the whole regular expression. The others are those substrings that matched parenthesized expressions within the regular expression, with parenthesized expressions numbered in left-to-right order of their opening parentheses. .PP .I Regsub copies \fIsource\fR to \fIdest\fR, making substitutions according to the most recent \fIregexec\fR performed using \fIprog\fR. Each instance of `&' in \fIsource\fR is replaced by the substring indicated by \fIstartp\fR[\fI0\fR] and \fIendp\fR[\fI0\fR]. Each instance of `\e\fIn\fR', where \fIn\fR is a digit, is replaced by the substring indicated by \fIstartp\fR[\fIn\fR] and \fIendp\fR[\fIn\fR]. To get a literal `&' or `\e\fIn\fR' into \fIdest\fR, prefix it with `\e'; to get a literal `\e' preceding `&' or `\e\fIn\fR', prefix it with another `\e'. .PP .I Regerror is called whenever an error is detected in \fIregcomp\fR, \fIregexec\fR, or \fIregsub\fR. The default \fIregerror\fR writes the string \fImsg\fR, with a suitable indicator of origin, on the standard error output and invokes \fIexit\fR(2). .I Regerror can be replaced by the user if other actions are desirable. .SH "REGULAR EXPRESSION SYNTAX" A regular expression is zero or more \fIbranches\fR, separated by `|'. It matches anything that matches one of the branches. .PP A branch is zero or more \fIpieces\fR, concatenated. It matches a match for the first, followed by a match for the second, etc. .PP A piece is an \fIatom\fR possibly followed by `*', `+', or `?'. An atom followed by `*' matches a sequence of 0 or more matches of the atom. An atom followed by `+' matches a sequence of 1 or more matches of the atom. An atom followed by `?' matches a match of the atom, or the null string. .PP An atom is a regular expression in parentheses (matching a match for the regular expression), a \fIrange\fR (see below), `.' (matching any single character), `^' (matching the null string at the beginning of the input string), `$' (matching the null string at the end of the input string), a `\e' followed by a single character (matching that character), or a single character with no other significance (matching that character). .PP A \fIrange\fR is a sequence of characters enclosed in `[]'. It normally matches any single character from the sequence. If the sequence begins with `^', it matches any single character \fInot\fR from the rest of the sequence. If two characters in the sequence are separated by `\-', this is shorthand for the full list of ASCII characters between them (e.g. `[0-9]' matches any decimal digit). To include a literal `]' in the sequence, make it the first character (following a possible `^'). To include a literal `\-', make it the first or last character. .SH AMBIGUITY If a regular expression could match two different parts of the input string, it will match the one which begins earliest. If both begin in the same place but match different lengths, or match the same length in different ways, life gets messier, as follows. .PP In general, the possibilities in a list of branches are considered in left-to-right order, the possibilities for `*', `+', and `?' are considered longest-first, nested constructs are considered from the outermost in, and concatenated constructs are considered leftmost-first. The match that will be chosen is the one that uses the earliest possibility in the first choice that has to be made. If there is more than one choice, the next will be made in the same manner (earliest possibility) subject to the decision on the first choice. And so forth. .PP For example, `(ab|a)b*c' could match `abc' in one of two ways. The first choice is between `ab' and `a'; since `ab' is earlier, and does lead to a successful overall match, it is chosen. Since the `b' is already spoken for, the `b*' must match its last possibility\(emthe empty string\(emsince it must respect the earlier choice. .PP In the particular case where no `|'s are present and there is only one `*', `+', or `?', the net effect is that the longest possible match will be chosen. So `ab*', presented with `xabbbby', will match `abbbb'. Note that if `ab*' is tried against `xabyabbbz', it will match `ab' just after `x', due to the begins-earliest rule. (In effect, the decision on where to start the match is the first choice to be made, hence subsequent choices must respect it even if this leads them to less-preferred alternatives.) .SH SEE ALSO egrep(1), expr(1) .SH DIAGNOSTICS \fIRegcomp\fR returns NULL for a failure (\fIregerror\fR permitting), where failures are syntax errors, exceeding implementation limits, or applying `+' or `*' to a possibly-null operand. .SH HISTORY Both code and manual page were written at U of T. They are intended to be compatible with the Bell V8 \fIregexp\fR(3), but are not derived from Bell code. .SH BUGS Empty branches and empty regular expressions are not portable to V8. .PP The restriction against applying `*' or `+' to a possibly-null operand is an artifact of the simplistic implementation. .PP Does not support \fIegrep\fR's newline-separated branches; neither does the V8 \fIregexp\fR(3), though. .PP Due to emphasis on compactness and simplicity, it's not strikingly fast. It does give special attention to handling simple cases quickly. End of regexp.3 echo regexp.c 1>&2 cat > regexp.c <<'End of regexp.c' /* * regcomp and regexec -- regsub and regerror are elsewhere * * Copyright (c) 1986 by University of Toronto. * Written by Henry Spencer. Not derived from licensed software. * * Permission is granted to anyone to use this software for any * purpose on any computer system, and to redistribute it freely, * subject to the following restrictions: * * 1. The author is not responsible for the consequences of use of * this software, no matter how awful, even if they arise * from defects in it. * * 2. The origin of this software must not be misrepresented, either * by explicit claim or by omission. * * 3. Altered versions must be plainly marked as such, and must not * be misrepresented as being the original software. * * Beware that some of this code is subtly aware of the way operator * precedence is structured in regular expressions. Serious changes in * regular-expression syntax might require a total rethink. */ #include <stdio.h> #include <regexp.h> #include "regmagic.h" /* * The "internal use only" fields in regexp.h are present to pass info from * compile to execute that permits the execute phase to run lots faster on * simple cases. They are: * * regstart char that must begin a match; '\0' if none obvious * reganch is the match anchored (at beginning-of-line only)? * regmust string (pointer into program) that match must include, or NULL * regmlen length of regmust string * * Regstart and reganch permit very fast decisions on suitable starting points * for a match, cutting down the work a lot. Regmust permits fast rejection * of lines that cannot possibly match. The regmust tests are costly enough * that regcomp() supplies a regmust only if the r.e. contains something * potentially expensive (at present, the only such thing detected is * or + * at the start of the r.e., which can involve a lot of backup). Regmlen is * supplied because the test in regexec() needs it and regcomp() is computing * it anyway. */ /* * Structure for regexp "program". This is essentially a linear encoding * of a nondeterministic finite-state machine (aka syntax charts or * "railroad normal form" in parsing technology). Each node is an opcode * plus a "next" pointer, possibly plus an operand. "Next" pointers of * all nodes except BRANCH implement concatenation; a "next" pointer with * a BRANCH on both ends of it is connecting two alternatives. (Here we * have one of the subtle syntax dependencies: an individual BRANCH (as * opposed to a collection of them) is never concatenated with anything * because of operator precedence.) The operand of some types of node is * a literal string; for others, it is a node leading into a sub-FSM. In * particular, the operand of a BRANCH node is the first node of the branch. * (NB this is *not* a tree structure: the tail of the branch connects * to the thing following the set of BRANCHes.) The opcodes are: */ /* definition number opnd? meaning */ #define END 0 /* no End of program. */ #define BOL 1 /* no Match "" at beginning of line. */ #define EOL 2 /* no Match "" at end of line. */ #define ANY 3 /* no Match any one character. */ #define ANYOF 4 /* str Match any character in this string. */ #define ANYBUT 5 /* str Match any character not in this string. */ #define BRANCH 6 /* node Match this alternative, or the next... */ #define BACK 7 /* no Match "", "next" ptr points backward. */ #define EXACTLY 8 /* str Match this string. */ #define NOTHING 9 /* no Match empty string. */ #define STAR 10 /* node Match this (simple) thing 0 or more times. */ #define PLUS 11 /* node Match this (simple) thing 1 or more times. */ #define OPEN 20 /* no Mark this point in input as start of #n. */ /* OPEN+1 is number 1, etc. */ #define CLOSE 30 /* no Analogous to OPEN. */ /* * Opcode notes: * * BRANCH The set of branches constituting a single choice are hooked * together with their "next" pointers, since precedence prevents * anything being concatenated to any individual branch. The * "next" pointer of the last BRANCH in a choice points to the * thing following the whole choice. This is also where the * final "next" pointer of each individual branch points; each * branch starts with the operand node of a BRANCH node. * * BACK Normal "next" pointers all implicitly point forward; BACK * exists to make loop structures possible. * * STAR,PLUS '?', and complex '*' and '+', are implemented as circular * BRANCH structures using BACK. Simple cases (one character * per match) are implemented with STAR and PLUS for speed * and to minimize recursive plunges. * * OPEN,CLOSE ...are numbered at compile time. */ /* * A node is one char of opcode followed by two chars of "next" pointer. * "Next" pointers are stored as two 8-bit pieces, high order first. The * value is a positive offset from the opcode of the node containing it. * An operand, if any, simply follows the node. (Note that much of the * code generation knows about this implicit relationship.) * * Using two bytes for the "next" pointer is vast overkill for most things, * but allows patterns to get big without disasters. */ #define OP(p) (*(p)) #define NEXT(p) (((*((p)+1)&0377)<<8) + *((p)+2)&0377) #define NEXT(p) (((*((p)+1)&0377)<<8) + (*((p)+2)&0377)) #define OPERAND(p) ((p) + 3) /* * See regmagic.h for one further detail of program structure. */ /* * Utility definitions. */ #ifndef CHARBITS #define UCHARAT(p) ((int)*(unsigned char *)(p)) #else #define UCHARAT(p) ((int)*(p)&CHARBITS) #endif #define FAIL(m) { regerror(m); return(NULL); } #define ISMULT(c) ((c) == '*' || (c) == '+' || (c) == '?') #define META "^$.[()|?+*\\" /* * Flags to be passed up and down. */ #define HASWIDTH 01 /* Known never to match null string. */ #define SIMPLE 02 /* Simple enough to be STAR/PLUS operand. */ #define SPSTART 04 /* Starts with * or +. */ #define WORST 0 /* Worst case. */ /* * Global work variables for regcomp(). */ static char *regparse; /* Input-scan pointer. */ static int regnpar; /* () count. */ static char regdummy; static char *regcode; /* Code-emit pointer; ®dummy = don't. */ static long regsize; /* Code size. */ /* * Forward declarations for regcomp()'s friends. */ #ifndef STATIC #define STATIC static #endif STATIC char *reg(); STATIC char *regbranch(); STATIC char *regpiece(); STATIC char *regatom(); STATIC char *regnode(); STATIC char *regnext(); STATIC void regc(); STATIC void reginsert(); STATIC void regtail(); STATIC void regoptail(); #ifdef STRCSPN STATIC int strcspn(); #endif /* - regcomp - compile a regular expression into internal code * * We can't allocate space until we know how big the compiled form will be, * but we can't compile it (and thus know how big it is) until we've got a * place to put the code. So we cheat: we compile it twice, once with code * generation turned off and size counting turned on, and once "for real". * This also means that we don't allocate space until we are sure that the * thing really will compile successfully, and we never have to move the * code and thus invalidate pointers into it. (Note that it has to be in * one piece because free() must be able to free it all.) * * Beware that the optimization-preparation code in here knows about some * of the structure of the compiled regexp. */ regexp * regcomp(exp) char *exp; { register regexp *r; register char *scan; register char *longest; register int len; int flags; extern char *malloc(); if (exp == NULL) FAIL("NULL argument"); /* First pass: determine size, legality. */ regparse = exp; regnpar = 1; regsize = 0L; regcode = ®dummy; regc(MAGIC); if (reg(0, &flags) == NULL) return(NULL); /* Small enough for pointer-storage convention? */ if (regsize >= 32767L) /* Probably could be 65535L. */ FAIL("regexp too big"); /* Allocate space. */ r = (regexp *)malloc(sizeof(regexp) + (unsigned)regsize); if (r == NULL) FAIL("out of space"); /* Second pass: emit code. */ regparse = exp; regnpar = 1; regcode = r->program; regc(MAGIC); if (reg(0, &flags) == NULL) return(NULL); /* Dig out information for optimizations. */ r->regstart = '\0'; /* Worst-case defaults. */ r->reganch = 0; r->regmust = NULL; r->regmlen = 0; scan = r->program+1; /* First BRANCH. */ if (OP(regnext(scan)) == END) { /* Only one top-level choice. */ scan = OPERAND(scan); /* Starting-point info. */ if (OP(scan) == EXACTLY) r->regstart = *OPERAND(scan); else if (OP(scan) == BOL) r->reganch++; /* * If there's something expensive in the r.e., find the * longest literal string that must appear and make it the * regmust. Resolve ties in favor of later strings, since * the regstart check works with the beginning of the r.e. * and avoiding duplication strengthens checking. Not a * strong reason, but sufficient in the absence of others. */ if (flags&SPSTART) { longest = NULL; len = 0; for (; scan != NULL; scan = regnext(scan)) if (OP(scan) == EXACTLY && strlen(OPERAND(scan)) >= len) { longest = OPERAND(scan); len = strlen(OPERAND(scan)); } r->regmust = longest; r->regmlen = len; } } return(r); } /* - reg - regular expression, i.e. main body or parenthesized thing * * Caller must absorb opening parenthesis. * * Combining parenthesis handling with the base level of regular expression * is a trifle forced, but the need to tie the tails of the branches to what * follows makes it hard to avoid. */ static char * reg(paren, flagp) int paren; /* Parenthesized? */ int *flagp; { register char *ret; register char *br; register char *ender; register int parno; int flags; *flagp = HASWIDTH; /* Tentatively. */ /* Make an OPEN node, if parenthesized. */ if (paren) { if (regnpar >= NSUBEXP) FAIL("too many ()"); parno = regnpar; regnpar++; ret = regnode(OPEN+parno); } else ret = NULL; /* Pick up the branches, linking them together. */ br = regbranch(&flags); if (br == NULL) return(NULL); if (ret != NULL) regtail(ret, br); /* OPEN -> first. */ else ret = br; if (!(flags&HASWIDTH)) *flagp &= ~HASWIDTH; *flagp |= flags&SPSTART; while (*regparse == '|') { regparse++; br = regbranch(&flags); if (br == NULL) return(NULL); regtail(ret, br); /* BRANCH -> BRANCH. */ if (!(flags&HASWIDTH)) *flagp &= ~HASWIDTH; *flagp |= flags&SPSTART; } /* Make a closing node, and hook it on the end. */ ender = regnode((paren) ? CLOSE+parno : END); regtail(ret, ender); /* Hook the tails of the branches to the closing node. */ for (br = ret; br != NULL; br = regnext(br)) regoptail(br, ender); /* Check for proper termination. */ if (paren && *regparse++ != ')') { FAIL("unmatched ()"); } else if (!paren && *regparse != '\0') { if (*regparse == ')') { FAIL("unmatched ()"); } else FAIL("junk on end"); /* "Can't happen". */ /* NOTREACHED */ } return(ret); } /* - regbranch - one alternative of an | operator * * Implements the concatenation operator. */ static char * regbranch(flagp) int *flagp; { register char *ret; register char *chain; register char *latest; int flags; *flagp = WORST; /* Tentatively. */ ret = regnode(BRANCH); chain = NULL; while (*regparse != '\0' && *regparse != '|' && *regparse != ')') { latest = regpiece(&flags); if (latest == NULL) return(NULL); *flagp |= flags&HASWIDTH; if (chain == NULL) /* First piece. */ *flagp |= flags&SPSTART; else regtail(chain, latest); chain = latest; } if (chain == NULL) /* Loop ran zero times. */ (void) regnode(NOTHING); return(ret); } /* - regpiece - something followed by possible [*+?] * * Note that the branching code sequences used for ? and the general cases * of * and + are somewhat optimized: they use the same NOTHING node as * both the endmarker for their branch list and the body of the last branch. * It might seem that this node could be dispensed with entirely, but the * endmarker role is not redundant. */ static char * regpiece(flagp) int *flagp; { register char *ret; register char op; register char *next; int flags; ret = regatom(&flags); if (ret == NULL) return(NULL); op = *regparse; if (!ISMULT(op)) { *flagp = flags; return(ret); } if (!(flags&HASWIDTH) && op != '?') FAIL("*+ operand could be empty"); *flagp = (op != '+') ? (WORST|SPSTART) : (WORST|HASWIDTH); if (op == '*' && (flags&SIMPLE)) reginsert(STAR, ret); else if (op == '*') { /* Emit x* as (x&|), where & means "self". */ reginsert(BRANCH, ret); /* Either x */ regoptail(ret, regnode(BACK)); /* and loop */ regoptail(ret, ret); /* back */ regtail(ret, regnode(BRANCH)); /* or */ regtail(ret, regnode(NOTHING)); /* null. */ } else if (op == '+' && (flags&SIMPLE)) reginsert(PLUS, ret); else if (op == '+') { /* Emit x+ as x(&|), where & means "self". */ next = regnode(BRANCH); /* Either */ regtail(ret, next); regtail(regnode(BACK), ret); /* loop back */ regtail(next, regnode(BRANCH)); /* or */ regtail(ret, regnode(NOTHING)); /* null. */ } else if (op == '?') { /* Emit x? as (x|) */ reginsert(BRANCH, ret); /* Either x */ regtail(ret, regnode(BRANCH)); /* or */ next = regnode(NOTHING); /* null. */ regtail(ret, next); regoptail(ret, next); } regparse++; if (ISMULT(*regparse)) FAIL("nested *?+"); return(ret); } /* - regatom - the lowest level * * Optimization: gobbles an entire sequence of ordinary characters so that * it can turn them into a single node, which is smaller to store and * faster to run. Backslashed characters are exceptions, each becoming a * separate node; the code is simpler that way and it's not worth fixing. */ static char * regatom(flagp) int *flagp; { register char *ret; int flags; *flagp = WORST; /* Tentatively. */ switch (*regparse++) { case '^': ret = regnode(BOL); break; case '$': ret = regnode(EOL); break; case '.': ret = regnode(ANY); *flagp |= HASWIDTH|SIMPLE; break; case '[': { register int class; register int classend; if (*regparse == '^') { /* Complement of range. */ ret = regnode(ANYBUT); regparse++; } else ret = regnode(ANYOF); if (*regparse == ']' || *regparse == '-') regc(*regparse++); while (*regparse != '\0' && *regparse != ']') { if (*regparse == '-') { regparse++; if (*regparse == ']' || *regparse == '\0') regc('-'); else { class = UCHARAT(regparse-2)+1; classend = UCHARAT(regparse); if (class > classend+1) FAIL("invalid [] range"); for (; class <= classend; class++) regc(class); regparse++; } } else regc(*regparse++); } regc('\0'); if (*regparse != ']') FAIL("unmatched []"); regparse++; *flagp |= HASWIDTH|SIMPLE; } break; case '(': ret = reg(1, &flags); if (ret == NULL) return(NULL); *flagp |= flags&(HASWIDTH|SPSTART); break; case '\0': case '|': case ')': FAIL("internal urp"); /* Supposed to be caught earlier. */ break; case '?': case '+': case '*': FAIL("?+* follows nothing"); break; case '\\': if (*regparse == '\0') FAIL("trailing \\"); ret = regnode(EXACTLY); regc(*regparse++); regc('\0'); *flagp |= HASWIDTH|SIMPLE; break; default: { register int len; register char ender; regparse--; len = strcspn(regparse, META); if (len <= 0) FAIL("internal disaster"); ender = *(regparse+len); if (len > 1 && ISMULT(ender)) len--; /* Back off clear of ?+* operand. */ *flagp |= HASWIDTH; if (len == 1) *flagp |= SIMPLE; ret = regnode(EXACTLY); while (len > 0) { regc(*regparse++); len--; } regc('\0'); } break; } return(ret); } /* - regnode - emit a node */ static char * /* Location. */ regnode(op) char op; { register char *ret; register char *ptr; ret = regcode; if (ret == ®dummy) { regsize += 3; return(ret); } ptr = ret; *ptr++ = op; *ptr++ = '\0'; /* Null "next" pointer. */ *ptr++ = '\0'; regcode = ptr; return(ret); } /* - regc - emit (if appropriate) a byte of code */ static void regc(b) char b; { if (regcode != ®dummy) *regcode++ = b; else regsize++; } /* - reginsert - insert an operator in front of already-emitted operand * * Means relocating the operand. */ static void reginsert(op, opnd) char op; char *opnd; { register char *src; register char *dst; register char *place; if (regcode == ®dummy) { regsize += 3; return; } src = regcode; regcode += 3; dst = regcode; while (src > opnd) *--dst = *--src; place = opnd; /* Op node, where operand used to be. */ *place++ = op; *place++ = '\0'; *place++ = '\0'; } /* - regtail - set the next-pointer at the end of a node chain */ static void regtail(p, val) char *p; char *val; { register char *scan; register char *temp; register int offset; if (p == ®dummy) return; /* Find last node. */ scan = p; for (;;) { temp = regnext(scan); if (temp == NULL) break; scan = temp; } if (OP(scan) == BACK) offset = scan - val; else offset = val - scan; *(scan+1) = (offset>>8)&0377; *(scan+2) = offset&0377; } /* - regoptail - regtail on operand of first argument; nop if operandless */ static void regoptail(p, val) char *p; char *val; { /* "Operandless" and "op != BRANCH" are synonymous in practice. */ if (p == NULL || p == ®dummy || OP(p) != BRANCH) return; regtail(OPERAND(p), val); } /* * regexec and friends */ /* * Global work variables for regexec(). */ static char *reginput; /* String-input pointer. */ static char *regbol; /* Beginning of input, for ^ check. */ static char **regstartp; /* Pointer to startp array. */ static char **regendp; /* Ditto for endp. */ /* * Forwards. */ STATIC int regtry(); STATIC int regmatch(); STATIC int regrepeat(); #ifdef DEBUG int regnarrate = 0; void regdump(); STATIC char *regprop(); #endif /* - regexec - match a regexp against a string */ int regexec(prog, string) register regexp *prog; register char *string; { register char *s; extern char *strchr(); /* Be paranoid... */ if (prog == NULL || string == NULL) { regerror("NULL parameter"); return(0); } /* Check validity of program. */ if (UCHARAT(prog->program) != MAGIC) { regerror("corrupted program"); return(0); } /* If there is a "must appear" string, look for it. */ if (prog->regmust != NULL) { s = string; while ((s = strchr(s, prog->regmust[0])) != NULL) { if (strncmp(s, prog->regmust, prog->regmlen) == 0) break; /* Found it. */ s++; } if (s == NULL) /* Not present. */ return(0); } /* Mark beginning of line for ^ . */ regbol = string; /* Simplest case: anchored match need be tried only once. */ if (prog->reganch) return(regtry(prog, string)); /* Messy cases: unanchored match. */ s = string; if (prog->regstart != '\0') /* We know what char it must start with. */ while ((s = strchr(s, prog->regstart)) != NULL) { if (regtry(prog, s)) return(1); s++; } else /* We don't -- general case. */ do { if (regtry(prog, s)) return(1); } while (*s++ != '\0'); /* Failure. */ return(0); } /* - regtry - try match at specific point */ static int /* 0 failure, 1 success */ regtry(prog, string) regexp *prog; char *string; { register int i; register char **sp; register char **ep; reginput = string; regstartp = prog->startp; regendp = prog->endp; sp = prog->startp; ep = prog->endp; for (i = NSUBEXP; i > 0; i--) { *sp++ = NULL; *ep++ = NULL; } if (regmatch(prog->program + 1)) { prog->startp[0] = string; prog->endp[0] = reginput; return(1); } else return(0); } /* - regmatch - main matching routine * * Conceptually the strategy is simple: check to see whether the current * node matches, call self recursively to see whether the rest matches, * and then act accordingly. In practice we make some effort to avoid * recursion, in particular by going through "ordinary" nodes (that don't * need to know whether the rest of the match failed) by a loop instead of * by recursion. */ static int /* 0 failure, 1 success */ regmatch(prog) char *prog; { register char *scan; /* Current node. */ char *next; /* Next node. */ extern char *strchr(); scan = prog; #ifdef DEBUG if (scan != NULL && regnarrate) fprintf(stderr, "%s(\n", regprop(scan)); #endif while (scan != NULL) { #ifdef DEBUG if (regnarrate) fprintf(stderr, "%s...\n", regprop(scan)); #endif next = regnext(scan); switch (OP(scan)) { case BOL: if (reginput != regbol) return(0); break; case EOL: if (*reginput != '\0') return(0); break; case ANY: if (*reginput == '\0') return(0); reginput++; break; case EXACTLY: { register int len; register char *opnd; opnd = OPERAND(scan); /* Inline the first character, for speed. */ if (*opnd != *reginput) return(0); len = strlen(opnd); if (len > 1 && strncmp(opnd, reginput, len) != 0) return(0); reginput += len; } break; case ANYOF: if (*reginput == '\0' || strchr(OPERAND(scan), *reginput) == NULL) return(0); reginput++; break; case ANYBUT: if (*reginput == '\0' || strchr(OPERAND(scan), *reginput) != NULL) return(0); reginput++; break; case NOTHING: break; case BACK: break; case OPEN+1: case OPEN+2: case OPEN+3: case OPEN+4: case OPEN+5: case OPEN+6: case OPEN+7: case OPEN+8: case OPEN+9: { register int no; register char *save; no = OP(scan) - OPEN; save = reginput; if (regmatch(next)) { /* * Don't set startp if some later * invocation of the same parentheses * already has. */ if (regstartp[no] == NULL) regstartp[no] = save; return(1); } else return(0); } break; case CLOSE+1: case CLOSE+2: case CLOSE+3: case CLOSE+4: case CLOSE+5: case CLOSE+6: case CLOSE+7: case CLOSE+8: case CLOSE+9: { register int no; register char *save; no = OP(scan) - CLOSE; save = reginput; if (regmatch(next)) { /* * Don't set endp if some later * invocation of the same parentheses * already has. */ if (regendp[no] == NULL) regendp[no] = save; return(1); } else return(0); } break; case BRANCH: { register char *save; if (OP(next) != BRANCH) /* No choice. */ next = OPERAND(scan); /* Avoid recursion. */ else { do { save = reginput; if (regmatch(OPERAND(scan))) return(1); reginput = save; scan = regnext(scan); } while (scan != NULL && OP(scan) == BRANCH); return(0); /* NOTREACHED */ } } break; case STAR: case PLUS: { register char nextch; register int no; register char *save; register int min; /* * Lookahead to avoid useless match attempts * when we know what character comes next. */ nextch = '\0'; if (OP(next) == EXACTLY) nextch = *OPERAND(next); min = (OP(scan) == STAR) ? 0 : 1; save = reginput; no = regrepeat(OPERAND(scan)); while (no >= min) { /* If it could work, try it. */ if (nextch == '\0' || *reginput == nextch) if (regmatch(next)) return(1); /* Couldn't or didn't -- back up. */ no--; reginput = save + no; } return(0); } break; case END: return(1); /* Success! */ break; default: regerror("memory corruption"); return(0); break; } scan = next; } /* * We get here only if there's trouble -- normally "case END" is * the terminating point. */ regerror("corrupted pointers"); return(0); } /* - regrepeat - repeatedly match something simple, report how many */ static int regrepeat(p) char *p; { register int count = 0; register char *scan; register char *opnd; scan = reginput; opnd = OPERAND(p); switch (OP(p)) { case ANY: count = strlen(scan); scan += count; break; case EXACTLY: while (*opnd == *scan) { count++; scan++; } break; case ANYOF: while (*scan != '\0' && strchr(opnd, *scan) != NULL) { count++; scan++; } break; case ANYBUT: while (*scan != '\0' && strchr(opnd, *scan) == NULL) { count++; scan++; } break; default: /* Oh dear. Called inappropriately. */ regerror("internal foulup"); count = 0; /* Best compromise. */ break; } reginput = scan; return(count); } /* - regnext - dig the "next" pointer out of a node */ static char * regnext(p) register char *p; { register int offset; if (p == ®dummy) return(NULL); offset = NEXT(p); if (offset == 0) return(NULL); if (OP(p) == BACK) return(p-offset); else return(p+offset); } #ifdef DEBUG STATIC char *regprop(); /* - regdump - dump a regexp onto stdout in vaguely comprehensible form */ void regdump(r) regexp *r; { register char *s; register char op = EXACTLY; /* Arbitrary non-END op. */ register char *next; extern char *strchr(); s = r->program + 1; while (op != END) { /* While that wasn't END last time... */ op = OP(s); printf("%2d%s", s-r->program, regprop(s)); /* Where, what. */ next = regnext(s); if (next == NULL) /* Next ptr. */ printf("(0)"); else printf("(%d)", (s-r->program)+(next-s)); s += 3; if (op == ANYOF || op == ANYBUT || op == EXACTLY) { /* Literal string, where present. */ while (*s != '\0') { putchar(*s); s++; } s++; } putchar('\n'); } /* Header fields of interest. */ if (r->regstart != '\0') printf("start `%c' ", r->regstart); if (r->reganch) printf("anchored "); if (r->regmust != NULL) printf("must have \"%s\"", r->regmust); printf("\n"); } /* - regprop - printable representation of opcode */ static char * regprop(op) char *op; { register char *p; static char buf[50]; (void) strcpy(buf, ":"); switch (OP(op)) { case BOL: p = "BOL"; break; case EOL: p = "EOL"; break; case ANY: p = "ANY"; break; case ANYOF: p = "ANYOF"; break; case ANYBUT: p = "ANYBUT"; break; case BRANCH: p = "BRANCH"; break; case EXACTLY: p = "EXACTLY"; break; case NOTHING: p = "NOTHING"; break; case BACK: p = "BACK"; break; case END: p = "END"; break; case OPEN+1: case OPEN+2: case OPEN+3: case OPEN+4: case OPEN+5: case OPEN+6: case OPEN+7: case OPEN+8: case OPEN+9: sprintf(buf+strlen(buf), "OPEN%d", OP(op)-OPEN); p = NULL; break; case CLOSE+1: case CLOSE+2: case CLOSE+3: case CLOSE+4: case CLOSE+5: case CLOSE+6: case CLOSE+7: case CLOSE+8: case CLOSE+9: sprintf(buf+strlen(buf), "CLOSE%d", OP(op)-CLOSE); p = NULL; break; case STAR: p = "STAR"; break; case PLUS: p = "PLUS"; break; default: regerror("corrupted opcode"); break; } if (p != NULL) (void) strcat(buf, p); return(buf); } #endif /* * The following is provided for those people who do not have strcspn() in * their C libraries. They should get off their butts and do something * about it; at least one public-domain implementation of those (highly * useful) string routines has been published on Usenet. */ #ifdef STRCSPN /* * strcspn - find length of initial segment of s1 consisting entirely * of characters not from s2 */ static int strcspn(s1, s2) char *s1; char *s2; { register char *scan1; register char *scan2; register int count; count = 0; for (scan1 = s1; *scan1 != '\0'; scan1++) { for (scan2 = s2; *scan2 != '\0';) /* ++ moved down. */ if (*scan1 == *scan2++) return(count); count++; } return(count); } #endif End of regexp.c echo regexp.h 1>&2 cat > regexp.h <<'End of regexp.h' /* * Definitions etc. for regexp(3) routines. * * Caveat: this is V8 regexp(3) [actually, a reimplementation thereof], * not the System V one. */ #define NSUBEXP 10 typedef struct regexp { char *startp[NSUBEXP]; char *endp[NSUBEXP]; char regstart; /* Internal use only. */ char reganch; /* Internal use only. */ char *regmust; /* Internal use only. */ int regmlen; /* Internal use only. */ char program[1]; /* Unwarranted chumminess with compiler. */ } regexp; extern regexp *regcomp(); extern int regexec(); extern void regsub(); extern void regerror(); End of regexp.h echo regmagic.h 1>&2 cat > regmagic.h <<'End of regmagic.h' /* * The first byte of the regexp internal "program" is actually this magic * number; the start node begins in the second byte. */ #define MAGIC 0234 End of regmagic.h echo regsub.c 1>&2 cat > regsub.c <<'End of regsub.c' /* * regsub * * Copyright (c) 1986 by University of Toronto. * Written by Henry Spencer. Not derived from licensed software. * * Permission is granted to anyone to use this software for any * purpose on any computer system, and to redistribute it freely, * subject to the following restrictions: * * 1. The author is not responsible for the consequences of use of * this software, no matter how awful, even if they arise * from defects in it. * * 2. The origin of this software must not be misrepresented, either * by explicit claim or by omission. * * 3. Altered versions must be plainly marked as such, and must not * be misrepresented as being the original software. */ #include <stdio.h> #include <regexp.h> #include "regmagic.h" #ifndef CHARBITS #define UCHARAT(p) ((int)*(unsigned char *)(p)) #else #define UCHARAT(p) ((int)*(p)&CHARBITS) #endif /* - regsub - perform substitutions after a regexp match */ void regsub(prog, source, dest) regexp *prog; char *source; char *dest; { register char *src; register char *dst; register char c; register int no; register int len; extern char *strncpy(); if (prog == NULL || source == NULL || dest == NULL) { regerror("NULL parm to regsub"); return; } if (UCHARAT(prog->program) != MAGIC) { regerror("damaged regexp fed to regsub"); return; } src = source; dst = dest; while ((c = *src++) != '\0') { if (c == '&') no = 0; else if (c == '\\' && '0' <= *src && *src <= '9') no = *src++ - '0'; else no = -1; if (no < 0) { /* Ordinary character. */ if (c == '\\' && (*src == '\\' || *src == '&')) c = *src++; *dst++ = c; } else if (prog->startp[no] != NULL && prog->endp[no] != NULL) { len = prog->endp[no] - prog->startp[no]; (void) strncpy(dst, prog->startp[no], len); dst += len; if (len != 0 && *(dst-1) == '\0') { /* strncpy hit NUL. */ regerror("damaged match string"); return; } } } *dst++ = '\0'; } End of regsub.c echo tests 1>&2 cat > tests <<'End of tests' abc abc y & abc abc xbc n - - abc axc n - - abc abx n - - abc xabcy y & abc abc ababc y & abc ab*c abc y & abc ab*bc abc y & abc ab*bc abbc y & abbc ab*bc abbbbc y & abbbbc ab+bc abbc y & abbc ab+bc abc n - - ab+bc abq n - - ab+bc abbbbc y & abbbbc ab?bc abbc y & abbc ab?bc abc y & abc ab?bc abbbbc n - - ab?c abc y & abc ^abc$ abc y & abc ^abc$ abcc n - - ^abc abcc y & abc ^abc$ aabc n - - abc$ aabc y & abc ^ abc y & $ abc y & a.c abc y & abc a.c axc y & axc a.*c axyzc y & axyzc a.*c axyzd n - - a[bc]d abc n - - a[bc]d abd y & abd a[b-d]e abd n - - a[b-d]e ace y & ace a[b-d] aac y & ac a[-b] a- y & a- a[b-] a- y & a- a[b-a] - c - - a[]b - c - - a[ - c - - a] a] y & a] a[]]b a]b y & a]b a[^bc]d aed y & aed a[^bc]d abd n - - a[^-b]c adc y & adc a[^-b]c a-c n - - a[^]b]c a]c n - - a[^]b]c adc y & adc ab|cd abc y & ab ab|cd abcd y & ab ()ef def y &-\1 ef- ()* - c - - *a - c - - ^* - c - - $* - c - - (*)b - c - - $b b n - - a\ - c - - a\(b a(b y &-\1 a(b- a\(*b ab y & ab a\(*b a((b y & a((b a\\b a\b y & a\b abc) - c - - (abc - c - - ((a)) abc y &-\1-\2 a-a-a (a)b(c) abc y &-\1-\2 abc-a-c a+b+c aabbabc y & abc a** - c - - a*? - c - - (a*)* - c - - (a*)+ - c - - (a|)* - c - - (a*|b)* - c - - (a+|b)* ab y &-\1 ab-b (a+|b)+ ab y &-\1 ab-b (a+|b)? ab y &-\1 a-a [^ab]* cde y & cde (^)* - c - - (ab|)* - c - - )( - c - - abc y & abc n - - a* y & ([abc])*d abbbcd y &-\1 abbbcd-c ([abc])*bcd abcd y &-\1 abcd-a a|b|c|d|e e y & e (a|b|c|d|e)f ef y &-\1 ef-e ((a*|b))* - c - - abcd*efg abcdefg y & abcdefg ab* xabyabbbz y & ab ab* xayabbbz y & a (ab|cd)e abcde y &-\1 cde-cd [abhgefdc]ij hij y & hij ^(ab|cd)e abcde n x\1y xy (abc|)ef abcdef y &-\1 ef- (a|b)c*d abcd y &-\1 bcd-b (ab|ab*)bc abc y &-\1 abc-a a([bc]*)c* abc y &-\1 abc-bc a([bc]*)(c*d) abcd y &-\1-\2 abcd-bc-d a([bc]+)(c*d) abcd y &-\1-\2 abcd-bc-d a([bc]*)(c+d) abcd y &-\1-\2 abcd-b-cd a[bcd]*dcdcde adcdcde y & adcdcde a[bcd]+dcdcde adcdcde n - - (ab|a)b*c abc y &-\1 abc-ab ((a)(b)c)(d) abcd y \1-\2-\3-\4 abc-a-b-d [a-zA-Z_][a-zA-Z0-9_]* alpha y & alpha ^a(bc+|b[eh])g|.h$ abh y &-\1 bh- (bc+d$|ef*g.|h?i(j|k)) effgz y &-\1-\2 effgz-effgz- (bc+d$|ef*g.|h?i(j|k)) ij y &-\1-\2 ij-ij-j (bc+d$|ef*g.|h?i(j|k)) effg n - - (bc+d$|ef*g.|h?i(j|k)) bcdd n - - (bc+d$|ef*g.|h?i(j|k)) reffgz y &-\1-\2 effgz-effgz- ((((((((((a)))))))))) - c - - (((((((((a))))))))) a y & a multiple words of text uh-uh n - - multiple words multiple words, yeah y & multiple words (.*)c(.*) abcde y &-\1-\2 abcde-ab-de $(.*), (.*)$ (a, b) y (\2, \1) (b, a) [k] ab n - - abcd abcd y &-\&-\\& abcd-&-\abcd a(bc)d abcd y \1-\\1-\\\1 bc-\1-\bc a[-]?c ac y & ac End of tests echo timer.c 1>&2 cat > timer.c <<'End of timer.c' /* * Simple timing program for regcomp(). * * Copyright (c) 1986 by University of Toronto. * Written by Henry Spencer. Not derived from licensed software. * * Permission is granted to anyone to use this software for any * purpose on any computer system, and to redistribute it freely, * subject to the following restrictions: * * 1. The author is not responsible for the consequences of use of * this software, no matter how awful, even if they arise * from defects in it. * * 2. The origin of this software must not be misrepresented, either * by explicit claim or by omission. * * 3. Altered versions must be plainly marked as such, and must not * be misrepresented as being the original software. * * Usage: timer ncomp nexec nsub * or * timer ncomp nexec nsub regexp string [ answer [ sub ] ] * * The second form is for timing repetitions of a single test case. * The first form's test data is a compiled-in copy of the "tests" file. * Ncomp, nexec, nsub are how many times to do each regcomp, regexec, * and regsub. The way to time an operation individually is to do something * like "timer 1 50 1". */ #include <stdio.h> struct try { char *re, *str, *ans, *src, *dst; } tests[] = { #include "timer.t.h" { NULL, NULL, NULL, NULL, NULL } }; #include <regexp.h> int errreport = 0; /* Report errors via errseen? */ char *errseen = NULL; /* Error message. */ char *progname; /* ARGSUSED */ main(argc, argv) int argc; char *argv[]; { int ncomp, nexec, nsub; struct try one; char dummy[512]; if (argc < 4) { ncomp = 1; nexec = 1; nsub = 1; } else { ncomp = atoi(argv[1]); nexec = atoi(argv[2]); nsub = atoi(argv[3]); } progname = argv[0]; if (argc > 5) { one.re = argv[4]; one.str = argv[5]; if (argc > 6) one.ans = argv[6]; else one.ans = "y"; if (argc > 7) { one.src = argv[7]; one.dst = "xxx"; } else { one.src = "x"; one.dst = "x"; } errreport = 1; try(one, ncomp, nexec, nsub); } else multiple(ncomp, nexec, nsub); exit(0); } void regerror(s) char *s; { if (errreport) errseen = s; else error(s, ""); } #ifndef ERRAVAIL error(s1, s2) char *s1; char *s2; { fprintf(stderr, "regexp: "); fprintf(stderr, s1, s2); fprintf(stderr, "\n"); exit(1); } #endif int lineno = 0; multiple(ncomp, nexec, nsub) int ncomp, nexec, nsub; { register int i; extern char *strchr(); errreport = 1; for (i = 0; tests[i].re != NULL; i++) { lineno++; try(tests[i], ncomp, nexec, nsub); } } try(fields, ncomp, nexec, nsub) struct try fields; int ncomp, nexec, nsub; { regexp *r; char dbuf[BUFSIZ]; register int i; errseen = NULL; r = regcomp(fields.re); if (r == NULL) { if (*fields.ans != 'c') complain("regcomp failure in `%s'", fields.re); return; } if (*fields.ans == 'c') { complain("unexpected regcomp success in `%s'", fields.re); free((char *)r); return; } for (i = ncomp-1; i > 0; i--) { free((char *)r); r = regcomp(fields.re); } if (!regexec(r, fields.str)) { if (*fields.ans != 'n') complain("regexec failure in `%s'", ""); free((char *)r); return; } if (*fields.ans == 'n') { complain("unexpected regexec success", ""); free((char *)r); return; } for (i = nexec-1; i > 0; i--) (void) regexec(r, fields.str); errseen = NULL; for (i = nsub; i > 0; i--) regsub(r, fields.src, dbuf); if (errseen != NULL) { complain("regsub complaint", ""); free((char *)r); return; } if (strcmp(dbuf, fields.dst) != 0) complain("regsub result `%s' wrong", dbuf); free((char *)r); } complain(s1, s2) char *s1; char *s2; { fprintf(stderr, "try: %d: ", lineno); fprintf(stderr, s1, s2); fprintf(stderr, " (%s)\n", (errseen != NULL) ? errseen : ""); } End of timer.c echo try.c 1>&2 cat > try.c <<'End of try.c' /* * Simple test program for regexp(3) stuff. Knows about debugging hooks. * * Copyright (c) 1986 by University of Toronto. * Written by Henry Spencer. Not derived from licensed software. * * Permission is granted to anyone to use this software for any * purpose on any computer system, and to redistribute it freely, * subject to the following restrictions: * * 1. The author is not responsible for the consequences of use of * this software, no matter how awful, even if they arise * from defects in it. * * 2. The origin of this software must not be misrepresented, either * by explicit claim or by omission. * * 3. Altered versions must be plainly marked as such, and must not * be misrepresented as being the original software. * * Usage: try re [string [output [-]]] * The re is compiled and dumped, regexeced against the string, the result * is applied to output using regsub(). The - triggers a running narrative * from regexec(). Dumping and narrative don't happen unless DEBUG. * * If there are no arguments, stdin is assumed to be a stream of lines with * five fields: a r.e., a string to match it against, a result code, a * source string for regsub, and the proper result. Result codes are 'c' * for compile failure, 'y' for match success, 'n' for match failure. * Field separator is tab. */ #include <stdio.h> #include <regexp.h> #ifdef ERRAVAIL char *progname; extern char *mkprogname(); #endif #ifdef DEBUG extern int regnarrate; #endif char buf[BUFSIZ]; int errreport = 0; /* Report errors via errseen? */ char *errseen = NULL; /* Error message. */ int status = 0; /* Exit status. */ /* ARGSUSED */ main(argc, argv) int argc; char *argv[]; { regexp *r; int i; #ifdef ERRAVAIL progname = mkprogname(argv[0]); #endif if (argc == 1) { multiple(); exit(status); } r = regcomp(argv[1]); if (r == NULL) error("regcomp failure", ""); #ifdef DEBUG regdump(r); if (argc > 4) regnarrate++; #endif if (argc > 2) { i = regexec(r, argv[2]); printf("%d", i); for (i = 1; i < NSUBEXP; i++) if (r->startp[i] != NULL && r->endp[i] != NULL) printf(" \\%d", i); printf("\n"); } if (argc > 3) { regsub(r, argv[3], buf); printf("%s\n", buf); } exit(status); } void regerror(s) char *s; { if (errreport) errseen = s; else error(s, ""); } #ifndef ERRAVAIL error(s1, s2) char *s1; char *s2; { fprintf(stderr, "regexp: "); fprintf(stderr, s1, s2); fprintf(stderr, "\n"); exit(1); } #endif int lineno; regexp badregexp; /* Implicit init to 0. */ multiple() { char rbuf[BUFSIZ]; char *field[5]; char *scan; int i; regexp *r; extern char *strchr(); errreport = 1; lineno = 0; while (fgets(rbuf, sizeof(rbuf), stdin) != NULL) { rbuf[strlen(rbuf)-1] = '\0'; /* Dispense with \n. */ lineno++; scan = rbuf; for (i = 0; i < 5; i++) { field[i] = scan; if (field[i] == NULL) { complain("bad testfile format", ""); exit(1); } scan = strchr(scan, '\t'); if (scan != NULL) *scan++ = '\0'; } try(field); } /* And finish up with some internal testing... */ lineno = 9990; errseen = NULL; if (regcomp((char *)NULL) != NULL || errseen == NULL) complain("regcomp(NULL) doesn't complain", ""); lineno = 9991; errseen = NULL; if (regexec((regexp *)NULL, "foo") || errseen == NULL) complain("regexec(NULL, ...) doesn't complain", ""); lineno = 9992; r = regcomp("foo"); if (r == NULL) { complain("regcomp(\"foo\") fails", ""); return; } lineno = 9993; errseen = NULL; if (regexec(r, (char *)NULL) || errseen == NULL) complain("regexec(..., NULL) doesn't complain", ""); lineno = 9994; errseen = NULL; regsub((regexp *)NULL, "foo", rbuf); if (errseen == NULL) complain("regsub(NULL, ..., ...) doesn't complain", ""); lineno = 9995; errseen = NULL; regsub(r, (char *)NULL, rbuf); if (errseen == NULL) complain("regsub(..., NULL, ...) doesn't complain", ""); lineno = 9996; errseen = NULL; regsub(r, "foo", (char *)NULL); if (errseen == NULL) complain("regsub(..., ..., NULL) doesn't complain", ""); lineno = 9997; errseen = NULL; if (regexec(&badregexp, "foo") || errseen == NULL) complain("regexec(nonsense, ...) doesn't complain", ""); lineno = 9998; errseen = NULL; regsub(&badregexp, "foo", rbuf); if (errseen == NULL) complain("regsub(nonsense, ..., ...) doesn't complain", ""); } try(fields) char **fields; { regexp *r; char dbuf[BUFSIZ]; errseen = NULL; r = regcomp(fields[0]); if (r == NULL) { if (*fields[2] != 'c') complain("regcomp failure in `%s'", fields[0]); return; } if (*fields[2] == 'c') { complain("unexpected regcomp success in `%s'", fields[0]); free((char *)r); return; } if (!regexec(r, fields[1])) { if (*fields[2] != 'n') complain("regexec failure in `%s'", ""); free((char *)r); return; } if (*fields[2] == 'n') { complain("unexpected regexec success", ""); free((char *)r); return; } errseen = NULL; regsub(r, fields[3], dbuf); if (errseen != NULL) { complain("regsub complaint", ""); free((char *)r); return; } if (strcmp(dbuf, fields[4]) != 0) complain("regsub result `%s' wrong", dbuf); free((char *)r); } complain(s1, s2) char *s1; char *s2; { fprintf(stderr, "try: %d: ", lineno); fprintf(stderr, s1, s2); fprintf(stderr, " (%s)\n", (errseen != NULL) ? errseen : ""); status = 1; } End of try.c -- Rich $alz rsalz@pineapple.bbn.com Cronus Project, BBN Labs "Anger is an energy"