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zsh/Src/pattern.c
2000-04-06 18:44:01 +00:00

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/*
* pattern.c - pattern matching
*
* This file is part of zsh, the Z shell.
*
* Copyright (c) 1999 Peter Stephenson
* All rights reserved.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and to distribute modified versions of this software for any
* purpose, provided that the above copyright notice and the following
* two paragraphs appear in all copies of this software.
*
* In no event shall Peter Stephenson or the Zsh Development Group be liable
* to any party for direct, indirect, special, incidental, or consequential
* damages arising out of the use of this software and its documentation,
* even if Peter Stephenson and the Zsh Development Group have been advised of
* the possibility of such damage.
*
* Peter Stephenson and the Zsh Development Group specifically disclaim any
* warranties, including, but not limited to, the implied warranties of
* merchantability and fitness for a particular purpose. The software
* provided hereunder is on an "as is" basis, and Peter Stephenson and the
* Zsh Development Group have no obligation to provide maintenance,
* support, updates, enhancements, or modifications.
*
* Pattern matching code derived from the regexp library by Henry
* Spencer, which has the following copyright.
*
* 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.
*
* Eagle-eyed readers will notice this is an altered version. Incredibly
* sharp-eyed readers might even find bits that weren't altered.
*/
#include "zsh.mdh"
/*
* The following union is used mostly for alignment purposes.
* Normal nodes are longs, while certain nodes take a char * as an argument;
* here we make sure that they both work out to the same length.
* The compiled regexp we construct consists of upats stuck together;
* anything else to be added (strings, numbers) is stuck after and
* then aligned to a whole number of upat units.
*
* Note also that offsets are in terms of the sizes of these things.
*/
union upat {
long l;
unsigned char *p;
};
typedef union upat *Upat;
#include "pattern.pro"
/* Number of active parenthesised expressions allowed in backreferencing */
#define NSUBEXP 9
/* definition number opnd? meaning */
#define P_END 0x00 /* no End of program. */
#define P_EXCSYNC 0x01 /* no Test if following exclude already failed */
#define P_EXCEND 0x02 /* no Test if exclude matched orig branch */
#define P_BACK 0x03 /* no Match "", "next" ptr points backward. */
#define P_EXACTLY 0x04 /* str Match this string. */
#define P_NOTHING 0x05 /* no Match empty string. */
#define P_ONEHASH 0x06 /* node Match this (simple) thing 0 or more times. */
#define P_TWOHASH 0x07 /* node Match this (simple) thing 1 or more times. */
#define P_GFLAGS 0x08 /* long Match nothing and set globbing flags */
#define P_ISSTART 0x09 /* no Match start of string. */
#define P_ISEND 0x0a /* no Match end of string. */
/* numbered so we can test bit 5 for a branch */
#define P_BRANCH 0x20 /* node Match this alternative, or the next... */
#define P_WBRANCH 0x21 /* uc* node P_BRANCH, but match at least 1 char */
/* excludes are also branches, but have bit 4 set, too */
#define P_EXCLUDE 0x30 /* uc* node Exclude this from previous branch */
#define P_EXCLUDP 0x31 /* uc* node Exclude, using full file path so far */
/* numbered so we can test bit 6 so as not to match initial '.' */
#define P_ANY 0x40 /* no Match any one character. */
#define P_ANYOF 0x41 /* str Match any character in this string. */
#define P_ANYBUT 0x42 /* str Match any character not in this string. */
#define P_STAR 0x43 /* no Match any set of characters. */
#define P_NUMRNG 0x44 /* zr, zr Match a numeric range. */
#define P_NUMFROM 0x45 /* zr Match a number >= X */
#define P_NUMTO 0x46 /* zr Match a number <= X */
#define P_NUMANY 0x47 /* no Match any set of decimal digits */
/* spaces left for P_OPEN+n,... for backreferences */
#define P_OPEN 0x80 /* no Mark this point in input as start of n. */
#define P_CLOSE 0x90 /* no Analogous to OPEN. */
/* zl is the range type zrange_t: may be zlong or unsigned long
* char is a single char
* uc* is a pointer to unsigned char, used at run time and initialised
* to NULL.
*/
/*
* Notes on usage:
* P_WBRANCH: This works like a branch and is used in complex closures,
* to ensure we don't succeed on a zero-length match of the pattern,
* since that would cause an infinite loop. We do this by recording
* the positions where we have already tried to match. See the
* P_WBRANCH test in patmatch().
*
* P_ANY, P_ANYOF: the operand is a null terminated
* string. Normal characters match as expected. Characters
* in the range Meta+PP_ALPHA..Meta+PP_UNKNWN do the approprate
* Posix range tests. This relies on imeta returning true for these
* characters. We treat unknown POSIX ranges as never matching.
* PP_RANGE means the next two (possibly metafied) characters form
* the limits of a range to test; it's too much like hard work to
* expand the range.
*
* P_EXCLUDE, P_EXCSYNC, PEXCEND: P_EXCLUDE appears in the pattern like
* P_BRANCH, but applies to the immediately preceding branch. The code in
* the corresponding branch is followed by a P_EXCSYNC, which simply
* acts as a marker that a P_EXCLUDE comes next. The P_EXCLUDE
* has a pointer to char embeded in it, which works
* like P_WBRANCH: if we get to the P_EXCSYNC, and we already matched
* up to the same position, fail. Thus we are forced to backtrack
* on closures in the P_BRANCH if the first attempt was excluded.
* Corresponding to P_EXCSYNC in the original branch, there is a
* P_EXCEND in the exclusion. If we get to this point, and we did
* *not* match in the original branch, the exclusion itself fails,
* otherwise it succeeds since we know the tail already matches,
* so P_EXCEND is the end of the exclusion test.
* The whole sorry mess looks like this, where the upper lines
* show the linkage of the branches, and the lower shows the linkage
* of their pattern arguments.
*
* --------------------- ----------------------
* ^ v ^ v
* ( <BRANCH>:apat-><EXCSYNC> <EXCLUDE>:excpat-><EXCEND> ) tail
* ^
* | |
* --------------------------------------
*
* P_EXCLUDP: this behaves exactly like P_EXCLUDE, with the sole exception
* that we prepend the path so far to the exclude pattern. This is
* for top level file globs, e.g. ** / *.c~*foo.c
* ^ I had to leave this space
* P_NUM*: zl is a zlong if that is 64-bit, else an unsigned long.
*/
#define PP_ALPHA 1
#define PP_ALNUM 2
#define PP_BLANK 3
#define PP_CNTRL 4
#define PP_DIGIT 5
#define PP_GRAPH 6
#define PP_LOWER 7
#define PP_PRINT 8
#define PP_PUNCT 9
#define PP_SPACE 10
#define PP_UPPER 11
#define PP_XDIGIT 12
#define PP_UNKWN 13
#define PP_RANGE 14
#define P_OP(p) ((p)->l & 0xff)
#define P_NEXT(p) ((p)->l >> 8)
#define P_OPERAND(p) ((p) + 1)
#define P_ISBRANCH(p) ((p)->l & 0x20)
#define P_ISEXCLUDE(p) (((p)->l & 0x30) == 0x30)
#define P_NOTDOT(p) ((p)->l & 0x40)
#define P_SIMPLE 0x01 /* Simple enough to be #/## operand. */
#define P_HSTART 0x02 /* Starts with # or ##'d pattern. */
#define P_PURESTR 0x04 /* Can be matched with a strcmp */
/* Next character after one which may be a Meta (x is any char *) */
#define METANEXT(x) (*(x) == Meta ? (x)+2 : (x)+1)
/*
* Increment pointer which may be on a Meta (x is a pointer variable),
* returning the incremented value (i.e. like pre-increment).
*/
#define METAINC(x) ((x) += (*(x) == Meta) ? 2 : 1)
/*
* Return unmetafied char from string (x is any char *)
*/
#define UNMETA(x) (*(x) == Meta ? (x)[1] ^ 32 : *(x))
#if defined(ZSH_64_BIT_TYPE) || defined(LONG_IS_64_BIT)
typedef zlong zrange_t;
#else
typedef unsigned long zrange_t;
#endif
/*
* Characters which terminate a pattern segment. We actually use
* a pointer patendseg which skips the first character if we are not
* parsing a file pattern.
* Note that the size of this and the next array are hard-wired
* via the definitions.
*/
static char endseg[] = {
'/', /* file only */
'\0', Bar, Outpar, /* all patterns */
Tilde /* extended glob only */
};
#define PATENDSEGLEN_NORM 4
#define PATENDSEGLEN_EXT 5
/* Characters which terminate a simple string */
static char endstr[] = {
'/', /* file only */
'\0', Bar, Outpar, Quest, Star, Inbrack, Inpar, Inang,
/* all patterns */
Tilde, Hat, Pound /* extended glob only */
};
#define PATENDSTRLEN_NORM 9
#define PATENDSTRLEN_EXT 12
/* Default size for pattern buffer */
#define P_DEF_ALLOC 256
/* Flags used in compilation */
static char *patstart, *patparse; /* input pointers */
static int patnpar; /* () count */
static char *patcode; /* point of code emission */
static long patsize; /* size of code */
static char *patout; /* start of code emission string */
static long patalloc; /* size allocated for same */
static char *patendseg; /* characters ending segment */
static int patendseglen; /* length of same */
static char *patendstr; /* characters ending plain string */
static int patendstrlen; /* length of sameo */
/* Flags used in both compilation and execution */
static int patflags; /* flags passed down to patcompile */
static int patglobflags; /* globbing flags & approx */
/* Add n more characters, ensuring there is enough space. */
/**/
static void
patadd(char *add, int ch, long n, int noalgn)
{
/* Make sure everything gets aligned unless we get noalgn. */
long newpatsize = patsize + n;
if (!noalgn)
newpatsize = (newpatsize + sizeof(union upat) - 1) &
~(sizeof(union upat) - 1);
if (patalloc < newpatsize) {
long newpatalloc =
2*(newpatsize > patalloc ? newpatsize : patalloc);
patout = (char *)zrealloc((char *)patout, newpatalloc);
patcode = patout + patsize;
patalloc = newpatalloc;
}
patsize = newpatsize;
if (add) {
while (n--)
*patcode++ = *add++;
} else
*patcode++ = ch;
patcode = patout + patsize;
}
static long rn_offs;
/* operates on pointers to union upat, returns a pointer */
#define PATNEXT(p) ((rn_offs = P_NEXT(p)) ? \
(P_OP(p) == P_BACK) ? \
((p)-rn_offs) : ((p)+rn_offs) : NULL)
/* Called before parsing a set of file matchs to initialize flags */
/**/
void
patcompstart(void)
{
patglobflags = 0;
}
/* Top level pattern compilation subroutine */
/**/
mod_export Patprog
patcompile(char *exp, int inflags, char **endexp)
{
int flags = 0, len = 0;
long startoff;
Upat pscan;
char *lng, *strp = NULL;
Patprog p;
startoff = sizeof(struct patprog);
/* Ensure alignment of start of program string */
startoff = (startoff + sizeof(union upat) - 1) & ~(sizeof(union upat) - 1);
/* Allocate reasonable sized chunk if none, reduce size if too big */
if (patalloc != P_DEF_ALLOC)
patout = (char *)zrealloc(patout, patalloc = P_DEF_ALLOC);
patcode = patout + startoff;
patsize = patcode - patout;
patstart = patparse = exp;
/*
* Note global patnpar numbers parentheses 1..9, while patnpar
* in struct is actual count of parentheses.
*/
patnpar = 1;
patflags = inflags & ~PAT_PURES;
patendseg = endseg;
patendseglen = isset(EXTENDEDGLOB) ? PATENDSEGLEN_EXT : PATENDSEGLEN_NORM;
patendstr = endstr;
patendstrlen = isset(EXTENDEDGLOB) ? PATENDSTRLEN_EXT : PATENDSTRLEN_NORM;
if (!(patflags & PAT_FILE)) {
patendseg++;
patendstr++;
patendseglen--;
patendstrlen--;
remnulargs(exp);
patglobflags = 0;
}
/*
* Have to be set now, since they get updated during compilation.
*/
((Patprog)patout)->globflags = patglobflags;
if (!(patflags & PAT_ANY)) {
/* Look for a really pure string, with no tokens at all. */
if (!patglobflags)
for (strp = exp; *strp &&
(!(patflags & PAT_FILE) || *strp != '/') && !itok(*strp);
strp++)
;
if (!strp || (*strp && *strp != '/')) {
/* No, do normal compilation. */
strp = NULL;
if (patcompswitch(0, &flags) == 0)
return NULL;
} else {
/* Yes, copy the string and skip compilation altogether */
patparse = strp;
len = strp - exp;
patadd(exp, 0, len + 1, 0);
patout[startoff + len] = '\0';
patflags |= PAT_PURES;
}
}
/* end of compilation: safe to use pointers */
p = (Patprog)patout;
p->startoff = startoff;
p->patstartch = '\0';
p->globend = patglobflags;
p->flags = patflags;
p->mustoff = 0;
p->size = patsize;
p->patmlen = len;
p->patnpar = patnpar-1;
if (!strp) {
pscan = (Upat)(patout + startoff);
if (!(patflags & PAT_ANY) && P_OP(PATNEXT(pscan)) == P_END) {
/* only one top level choice */
pscan = P_OPERAND(pscan);
if (flags & P_PURESTR) {
/*
* The pattern can be matched with a simple strncmp/strcmp.
* Careful in case we've overwritten the node for the next ptr.
*/
char *dst = patout + startoff;
Upat next;
p->flags |= PAT_PURES;
for (; pscan; pscan = next) {
next = PATNEXT(pscan);
if (P_OP(pscan) == P_EXACTLY) {
char *opnd = (char *)P_OPERAND(pscan);
while ((*dst = *opnd++))
dst++;
}
}
*dst++ = '\0';
p->size = dst - patout;
/* patmlen is really strlen, don't include null byte */
p->patmlen = p->size - startoff - 1;
} else {
/* starting point info */
if (P_OP(pscan) == P_EXACTLY && !p->globflags)
p->patstartch = *(char *)P_OPERAND(pscan);
/*
* Find the longest literal string in something expensive.
* This is itself not all that cheap if we have
* case-insensitive matching or approximation, so don't.
*/
if ((flags & P_HSTART) && !p->globflags) {
lng = NULL;
len = 0;
for (; pscan; pscan = PATNEXT(pscan))
if (P_OP(pscan) == P_EXACTLY &&
strlen((char *)P_OPERAND(pscan)) >= len) {
lng = (char *)P_OPERAND(pscan);
len = strlen(lng);
}
if (lng) {
p->mustoff = lng - patout;
p->patmlen = len;
}
}
}
}
}
/*
* The pattern was compiled in a fixed buffer: unless told otherwise,
* we stick the compiled pattern on the heap. This is necessary
* for files where we will often be compiling multiple segments at once.
* But if we get the ZDUP flag w always put it in zalloc()ed memory.
*/
if (patflags & PAT_ZDUP) {
Patprog newp = (Patprog)zalloc(patsize);
memcpy((char *)newp, (char *)p, patsize);
p = newp;
} else if (!(patflags & PAT_STATIC)) {
Patprog newp = (Patprog)zhalloc(patsize);
memcpy((char *)newp, (char *)p, patsize);
p = newp;
}
if (endexp)
*endexp = patparse;
return p;
}
/*
* Main body or parenthesised subexpression in pattern
* Parenthesis (and any ksh_glob gubbins) will have been removed.
*/
/**/
static long
patcompswitch(int paren, int *flagp)
{
long starter, br, ender, excsync = 0;
int parno = 0;
int flags, gfchanged = 0, savglobflags = patglobflags;
Upat ptr;
*flagp = 0;
if (paren && (patglobflags & GF_BACKREF) && patnpar <= NSUBEXP) {
/*
* parenthesized: make an open node.
* We can only refer to the first nine parentheses.
* For any others, we just use P_OPEN on its own; there's
* no gain in arbitrarily limiting the number of parentheses.
*/
parno = patnpar++;
starter = patnode(P_OPEN + parno);
} else
starter = 0;
br = patnode(P_BRANCH);
if (!patcompbranch(&flags))
return 0;
if (patglobflags != savglobflags)
gfchanged++;
if (starter)
pattail(starter, br);
else
starter = br;
*flagp |= flags & (P_HSTART|P_PURESTR);
while (*patparse == Bar ||
(isset(EXTENDEDGLOB) && *patparse == Tilde &&
(patparse[1] == '/' ||
!memchr(patendseg, patparse[1], patendseglen)))) {
int tilde = *patparse++ == Tilde;
long gfnode = 0, newbr;
*flagp &= ~P_PURESTR;
if (tilde) {
union upat up;
/* excsync remembers the P_EXCSYNC node before a chain of
* exclusions: all point back to this. only the
* original (non-excluded) branch gets a trailing P_EXCSYNC.
*/
if (!excsync) {
excsync = patnode(P_EXCSYNC);
patoptail(br, excsync);
}
/*
* By default, approximations are turned off in exclusions:
* we need to do this here as otherwise the code compiling
* the exclusion doesn't know if the flags have really
* changed if the error count gets restored.
*
* At top level (paren == 0) in a file glob !(patflags &PAT_FILET)
* do the exclusion prepending the file path so far, else don't.
*/
patglobflags &= ~0xff;
br = patnode(!(patflags & PAT_FILET) || paren ?
P_EXCLUDE : P_EXCLUDP);
up.p = NULL;
patadd((char *)&up, 0, sizeof(up), 0);
/* / is not treated as special if we are at top level */
if (!paren && *patendseg == '/') {
tilde++;
patendseg++;
patendseglen--;
patendstr++;
patendstrlen--;
}
} else {
excsync = 0;
br = patnode(P_BRANCH);
/*
* The position of the following statements means globflags
* set in the main branch carry over to the exclusion.
*/
if (!paren) {
patglobflags = 0;
if (((Patprog)patout)->globflags) {
/*
* If at top level, we need to reinitialize flags to zero,
* since (#i)foo|bar only applies to foo and we stuck
* the #i into the global flags.
* We could have done it so that they only got set in the
* first branch, but it's quite convenient having any
* global flags set in the header and not buried in the
* pattern. (Or maybe it isn't and we should
* forget this bit and always stick in an explicit GFLAGS
* statement instead of using the header.)
* Also, this can't happen for file globs where there are
* no top-level |'s.
*
* No gfchanged, as nothing to follow branch at top
* level.
*/
union upat up;
gfnode = patnode(P_GFLAGS);
up.l = patglobflags;
patadd((char *)&up, 0, sizeof(union upat), 0);
}
} else {
patglobflags = savglobflags;
}
}
newbr = patcompbranch(&flags);
if (tilde == 2) {
/* restore special treatment of / */
patendseg--;
patendseglen++;
patendstr--;
patendstrlen++;
}
if (!newbr)
return 0;
if (gfnode)
pattail(gfnode, newbr);
if (!tilde && patglobflags != savglobflags)
gfchanged++;
pattail(starter, br);
if (excsync)
patoptail(br, patnode(P_EXCEND));
*flagp |= flags & P_HSTART;
}
/*
* Make a closing node, hooking it to the end.
* Note that we can't optimize P_NOTHING out here, since another
* branch at that point would indicate the current choices continue,
* which they don't.
*/
ender = patnode(paren ? parno ? P_CLOSE+parno : P_NOTHING : P_END);
pattail(starter, ender);
/*
* Hook the tails of the branches to the closing node,
* except for exclusions which terminate where they are.
*/
for (ptr = (Upat)patout + starter; ptr; ptr = PATNEXT(ptr))
if (!P_ISEXCLUDE(ptr))
patoptail(ptr-(Upat)patout, ender);
/* check for proper termination */
if ((paren && *patparse++ != Outpar) ||
(!paren && *patparse &&
!((patflags & PAT_FILE) && *patparse == '/')))
return 0;
if (paren && gfchanged) {
/*
* Restore old values of flags when leaving parentheses.
* gfchanged detects a change in any branch (except exclusions
* which are separate), since we need to emit this even if
* a later branch happened to put the flags back.
*/
pattail(ender, patnode(P_GFLAGS));
patglobflags = savglobflags;
patadd((char *)&savglobflags, 0, sizeof(long), 0);
}
return starter;
}
/*
* Compile something ended by Bar, Outpar, Tilde, or end of string.
* Note the BRANCH or EXCLUDE tag must already have been omitted:
* this returns the position of the operand of that.
*/
/**/
static long
patcompbranch(int *flagp)
{
long chain, latest, starter;
int flags;
*flagp = P_PURESTR;
starter = chain = 0;
while (!memchr(patendseg, *patparse, patendseglen) ||
(*patparse == Tilde && patparse[1] != '/' &&
memchr(patendseg, patparse[1], patendseglen))) {
if (isset(EXTENDEDGLOB) &&
((!isset(SHGLOB) &&
(*patparse == Inpar && patparse[1] == Pound)) ||
(isset(KSHGLOB) && *patparse == '@' && patparse[1] == Inpar &&
patparse[2] == Pound))) {
/* Globbing flags. */
char *pp1 = patparse;
int oldglobflags = patglobflags;
long assert;
patparse += (*patparse == '@') ? 3 : 2;
if (!patgetglobflags(&patparse, &assert))
return 0;
if (assert) {
/*
* Start/end assertion looking like flags, but
* actually handled as a normal node
*/
latest = patnode(assert);
flags = 0;
} else {
if (pp1 == patstart) {
/* Right at start of pattern, the simplest case.
* Put them into the flags and don't emit anything.
*/
((Patprog)patout)->globflags = patglobflags;
continue;
} else if (!*patparse) {
/* Right at the end, so just leave the flags for
* the next Patprog in the chain to pick up.
*/
break;
}
/*
* Otherwise, we have to stick them in as a pattern
* matching nothing.
*/
if (oldglobflags != patglobflags) {
/* Flags changed */
union upat up;
latest = patnode(P_GFLAGS);
up.l = patglobflags;
patadd((char *)&up, 0, sizeof(union upat), 0);
} else {
/* No effect. */
continue;
}
}
} else if (isset(EXTENDEDGLOB) && *patparse == Hat) {
/*
* ^pat: anything but pat. For proper backtracking,
* etc., we turn this into (*~pat), except without the
* parentheses.
*/
patparse++;
latest = patcompnot(0, &flags);
} else
latest = patcomppiece(&flags);
if (!latest)
return 0;
if (!starter)
starter = latest;
if (!(flags & P_PURESTR))
*flagp &= ~P_PURESTR;
if (!chain)
*flagp |= flags & P_HSTART;
else
pattail(chain, latest);
chain = latest;
}
/* check if there was nothing in the loop, i.e. () */
if (!chain)
starter = patnode(P_NOTHING);
return starter;
}
/* get glob flags, return 1 for success, 0 for failure */
/**/
int
patgetglobflags(char **strp, long *assertp)
{
char *nptr, *ptr = *strp;
zlong ret;
*assertp = 0;
/* (#X): assumes we are still positioned on the first X */
for (; *ptr && *ptr != Outpar; ptr++) {
switch (*ptr) {
case 'a':
/* Approximate matching, max no. of errors follows */
ret = zstrtol(++ptr, &nptr, 10);
/*
* We can't have more than 254, because we need 255 to
* mark 254 errors in wbranch and exclude sync strings
* (hypothetically --- hope no-one tries it).
*/
if (ret < 0 || ret > 254 || ptr == nptr)
return 0;
patglobflags = (patglobflags & ~0xff) | (ret & 0xff);
ptr = nptr-1;
break;
case 'l':
/* Lowercase in pattern matches lower or upper in target */
patglobflags = (patglobflags & ~GF_IGNCASE) | GF_LCMATCHUC;
break;
case 'i':
/* Fully case insensitive */
patglobflags = (patglobflags & ~GF_LCMATCHUC) | GF_IGNCASE;
break;
case 'I':
/* Restore case sensitivity */
patglobflags &= ~(GF_LCMATCHUC|GF_IGNCASE);
break;
case 'b':
/* Make backreferences */
patglobflags |= GF_BACKREF;
break;
case 'B':
/* Don't make backreferences */
patglobflags &= ~GF_BACKREF;
break;
case 'm':
/* Make references to complete match */
patglobflags |= GF_MATCHREF;
break;
case 'M':
/* Don't */
patglobflags &= ~GF_MATCHREF;
break;
case 's':
*assertp = P_ISSTART;
break;
case 'e':
*assertp = P_ISEND;
break;
default:
return 0;
}
}
if (*ptr != Outpar)
return 0;
/* Start/end assertions must appear on their own. */
if (*assertp && (*strp)[1] != Outpar)
return 0;
*strp = ptr + 1;
return 1;
}
/*
* compile a chunk such as a literal string or a [...] followed
* by a possible hash operator
*/
/**/
static long
patcomppiece(int *flagp)
{
long starter, next, pound, op;
int flags, flags2, kshchar, len, ch, patch;
union upat up;
char *nptr, *str0, cbuf[2];
zrange_t from, to;
flags = 0;
str0 = patparse;
for (;;) {
/*
* Check if we have a string. First, we need to make sure
* the string doesn't introduce a ksh-like parenthesised expression.
*/
kshchar = '\0';
if (isset(KSHGLOB) && *patparse && patparse[1] == Inpar) {
if (strchr("?*+!@", *patparse))
kshchar = STOUC(*patparse);
else if (*patparse == Star || *patparse == Quest)
kshchar = STOUC(ztokens[*patparse - Pound]);
}
/*
* End of string (or no string at all) if ksh-type parentheses,
* or special character, unless that character is a tilde and
* the character following is an end-of-segment character. Thus
* tildes are not special if there is nothing following to
* be excluded.
*/
if (kshchar || (memchr(patendstr, *patparse, patendstrlen) &&
(*patparse != Tilde ||
patparse[1] == '/' ||
!memchr(patendseg, patparse[1], patendseglen))))
break;
METAINC(patparse);
}
if (patparse > str0) {
/* Ordinary string: cancel kshchar lookahead */
kshchar = '\0';
/*
* Assume it matches a simple string until we find otherwise.
*/
flags |= P_PURESTR;
DPUTS(patparse == str0, "BUG: matched nothing in patcomppiece.");
/* more than one character matched? */
len = str0 + (*str0 == Meta ? 2 : 1) < patparse;
/*
* If we have more than one character, a following hash only
* applies to the last, so decrement.
*/
if (isset(EXTENDEDGLOB) && *patparse == Pound && len)
patparse -= (patparse > str0 + 1 && patparse[-2] == Meta) ? 2 : 1;
/*
* If len is 1, we can't have an active # following, so doesn't
* matter that we don't make X in `XX#' simple.
*/
if (!len)
flags |= P_SIMPLE;
starter = patnode(P_EXACTLY);
/* add enough space including null byte */
len = patparse - str0;
patadd(str0, 0, len + 1, 0);
nptr = (char *)P_OPERAND((Upat)patout + starter);
nptr[len] = '\0';
/*
* It's much simpler to turn off pure string mode for
* any case-insensitive or approximate matching; usually,
* that is correct, or they wouldn't have been turned on.
* However, we need to make sure we match a "." or ".."
* in a file name as a pure string. There's a minor bug
* that this will also apply to something like
* ..(#a1).. (i.e. the (#a1) has no effect), but if you're
* going to write funny patterns, you get no sympathy from me.
*/
if (patglobflags &&
(!(patflags & PAT_FILE) || (strcmp(nptr, ".") &&
strcmp(nptr, ".."))))
flags &= ~P_PURESTR;
for (; *nptr; METAINC(nptr))
if (itok(*nptr))
*nptr = ztokens[*nptr - Pound];
} else {
if (kshchar)
patparse++;
patch = *patparse;
METAINC(patparse);
switch(patch) {
case Quest:
flags |= P_SIMPLE;
starter = patnode(P_ANY);
break;
case Star:
/* kshchar is used as a sign that we can't have #'s. */
kshchar = -1;
starter = patnode(P_STAR);
break;
case Inbrack:
flags |= P_SIMPLE;
if (*patparse == Hat || *patparse == '^' || *patparse == '!') {
patparse++;
starter = patnode(P_ANYBUT);
} else
starter = patnode(P_ANYOF);
if (*patparse == Outbrack) {
patparse++;
patadd(NULL, ']', 1, 1);
}
while (*patparse && *patparse != Outbrack) {
/* Meta is not a token */
if (*patparse == Inbrack && patparse[1] == ':' &&
(nptr = strchr(patparse+2, ':')) &&
nptr[1] == Outbrack) {
/* Posix range. */
patparse += 2;
len = nptr - patparse;
if (!strncmp(patparse, "alpha", len))
ch = PP_ALPHA;
else if (!strncmp(patparse, "alnum", len))
ch = PP_ALNUM;
else if (!strncmp(patparse, "blank", len))
ch = PP_BLANK;
else if (!strncmp(patparse, "cntrl", len))
ch = PP_CNTRL;
else if (!strncmp(patparse, "digit", len))
ch = PP_DIGIT;
else if (!strncmp(patparse, "graph", len))
ch = PP_GRAPH;
else if (!strncmp(patparse, "lower", len))
ch = PP_LOWER;
else if (!strncmp(patparse, "print", len))
ch = PP_PRINT;
else if (!strncmp(patparse, "punct", len))
ch = PP_PUNCT;
else if (!strncmp(patparse, "space", len))
ch = PP_SPACE;
else if (!strncmp(patparse, "upper", len))
ch = PP_UPPER;
else if (!strncmp(patparse, "xdigit", len))
ch = PP_XDIGIT;
else
ch = PP_UNKWN;
patparse = nptr + 2;
if (ch != PP_UNKWN)
patadd(NULL, STOUC(Meta+ch), 1, 1);
continue;
}
if (itok(*patparse)) {
cbuf[0] = ztokens[*patparse - Pound];
} else if (*patparse == Meta) {
cbuf[0] = Meta;
cbuf[1] = *++patparse;
} else
cbuf[0] = *patparse;
patparse++;
if (*patparse == '-' && patparse[1] != Outbrack) {
patadd(NULL, STOUC(Meta+PP_RANGE), 1, 1);
patadd(cbuf, 0, (cbuf[0] == Meta) ? 2 : 1, 1);
if (itok(*++patparse)) {
patadd(0, STOUC(ztokens[*patparse - Pound]), 1, 1);
} else
patadd(patparse, 0, (*patparse == Meta) ? 2 : 1, 1);
METAINC(patparse);
} else
patadd(cbuf, 0, (cbuf[0] == Meta) ? 2 : 1, 1);
}
if (*patparse != Outbrack)
return 0;
patparse++;
/* terminate null string and fix alignment */
patadd(NULL, 0, 1, 0);
break;
case Inpar:
/* is this how to treat parentheses in SHGLOB? */
if (isset(SHGLOB) && !kshchar)
return 0;
if (kshchar == '!') {
/* This is nasty, we should really either handle all
* kshglobbing below or here. But most of the
* others look like non-ksh patterns, while this one
* doesn't, so we handle it here and leave the rest.
* We treat it like an extendedglob ^, except that
* it goes into parentheses.
*
* If we did do kshglob here, we could support
* the old behaviour that things like !(foo)##
* work, but it makes the code more complicated at
* the expense of allowing the user to do things
* they shouldn't.
*/
if (!(starter = patcompnot(1, &flags2)))
return 0;
} else if (!(starter = patcompswitch(1, &flags2)))
return 0;
flags |= flags2 & P_HSTART;
break;
case Inang:
/* Numeric glob */
len = 0; /* beginning present 1, end present 2 */
if (idigit(*patparse)) {
from = (zrange_t) zstrtol((char *)patparse,
(char **)&nptr, 10);
patparse = nptr;
len |= 1;
}
DPUTS(*patparse != '-', "BUG: - missing from numeric glob");
patparse++;
if (idigit(*patparse)) {
to = (zrange_t) zstrtol((char *)patparse,
(char **)&nptr, 10);
patparse = nptr;
len |= 2;
}
if (*patparse != Outang)
return 0;
patparse++;
starter = 0; /* shut compiler up */
switch(len) {
case 3:
starter = patnode(P_NUMRNG);
patadd((char *)&from, 0, sizeof(from), 0);
patadd((char *)&to, 0, sizeof(to), 0);
break;
case 2:
starter = patnode(P_NUMTO);
patadd((char *)&to, 0, sizeof(to), 0);
break;
case 1:
starter = patnode(P_NUMFROM);
patadd((char *)&from, 0, sizeof(from), 0);
break;
case 0:
starter = patnode(P_NUMANY);
break;
}
/* This can't be simple, because it isn't.
* Mention in manual that matching digits with [...]
* is more efficient.
*/
break;
case Pound:
DPUTS(!isset(EXTENDEDGLOB), "BUG: # not treated as string");
/*
* A hash here is an error; it should follow something
* repeatable.
*/
return 0;
break;
#ifdef DEBUG
default:
dputs("BUG: character not handled in patcomppiece");
return 0;
break;
#endif
}
}
if (!(pound = (*patparse == Pound && isset(EXTENDEDGLOB))) &&
(kshchar <= 0 || kshchar == '@' || kshchar == '!')) {
*flagp = flags;
return starter;
}
/* too much at once doesn't currently work */
if (kshchar && pound)
return 0;
if (kshchar == '*') {
op = P_ONEHASH;
*flagp = P_HSTART;
} else if (kshchar == '+') {
op = P_TWOHASH;
*flagp = P_HSTART;
} else if (kshchar == '?') {
op = 0;
*flagp = 0;
} else if (*++patparse == Pound) {
op = P_TWOHASH;
patparse++;
*flagp = P_HSTART;
} else {
op = P_ONEHASH;
*flagp = P_HSTART;
}
/*
* Note optimizations with pointers into P_NOTHING branches: some
* should logically point to next node after current piece.
*
* Backtracking is also encoded in a slightly obscure way: the
* code emitted ensures we test the non-empty branch of complex
* patterns before the empty branch on each repetition. Hence
* each time we fail on a non-empty branch, we try the empty branch,
* which is equivalent to backtracking.
*/
if ((flags & P_SIMPLE) && op == P_ONEHASH &&
P_OP((Upat)patout+starter) == P_ANY) {
/* Optimize ?# to *. Silly thing to do, since who would use
* use ?# ? But it makes the later code shorter.
*/
Upat uptr = (Upat)patout + starter;
uptr->l = (uptr->l & ~0xff) | P_STAR;
} else if ((flags & P_SIMPLE) && op && !(patglobflags & 0xff)) {
/* Don't simplify if we need to look for approximations. */
patinsert(op, starter, NULL, 0);
} else if (op == P_ONEHASH) {
/* Emit x# as (x&|), where & means "self". */
up.p = NULL;
patinsert(P_WBRANCH, starter, (char *)&up, sizeof(up));
/* Either x */
patoptail(starter, patnode(P_BACK)); /* and loop */
patoptail(starter, starter); /* back */
pattail(starter, patnode(P_BRANCH)); /* or */
pattail(starter, patnode(P_NOTHING)); /* null. */
} else if (op == P_TWOHASH) {
/* Emit x## as x(&|) where & means "self". */
next = patnode(P_WBRANCH); /* Either */
up.p = NULL;
patadd((char *)&up, 0, sizeof(up), 0);
pattail(starter, next);
pattail(patnode(P_BACK), starter); /* loop back */
pattail(next, patnode(P_BRANCH)); /* or */
pattail(starter, patnode(P_NOTHING)); /* null. */
} else if (kshchar == '?') {
/* Emit ?(x) as (x|) */
patinsert(P_BRANCH, starter, NULL, 0); /* Either x */
pattail(starter, patnode(P_BRANCH)); /* or */
next = patnode(P_NOTHING); /* null */
pattail(starter, next);
patoptail(starter, next);
}
if (*patparse == Pound)
return 0;
return starter;
}
/*
* Turn a ^foo (paren = 0) or !(foo) (paren = 1) into *~foo with
* parentheses if necessary. As you see, that's really quite easy.
*/
/**/
static long
patcompnot(int paren, int *flagsp)
{
union upat up;
long excsync, br, excl, n, starter;
int dummy;
/* Here, we're matching a star at the start. */
*flagsp = P_HSTART;
starter = patnode(P_BRANCH);
br = patnode(P_STAR);
excsync = patnode(P_EXCSYNC);
pattail(br, excsync);
pattail(starter, excl = patnode(P_EXCLUDE));
up.p = NULL;
patadd((char *)&up, 0, sizeof(up), 0);
if (!(br = (paren ? patcompswitch(1, &dummy) : patcompbranch(&dummy))))
return 0;
pattail(br, patnode(P_EXCEND));
n = patnode(P_NOTHING); /* just so much easier */
pattail(excsync, n);
pattail(excl, n);
return starter;
}
/* Emit a node */
/**/
static long
patnode(long op)
{
long starter = (Upat)patcode - (Upat)patout;
union upat up;
up.l = op;
patadd((char *)&up, 0, sizeof(union upat), 0);
return starter;
}
/*
* insert an operator in front of an already emitted operand:
* we relocate the operand. there had better be nothing else after.
*/
/**/
static void
patinsert(long op, int opnd, char *xtra, int sz)
{
char *src, *dst, *opdst;
union upat buf, *lptr;
buf.l = 0;
patadd((char *)&buf, 0, sizeof(buf), 0);
if (sz)
patadd(xtra, 0, sz, 0);
src = patcode - sizeof(union upat) - sz;
dst = patcode;
opdst = patout + opnd * sizeof(union upat);
while (src > opdst)
*--dst = *--src;
/* A cast can't be an lvalue */
lptr = (Upat)opdst;
lptr->l = op;
opdst += sizeof(union upat);
while (sz--)
*opdst++ = *xtra++;
}
/* set the 'next' pointer at the end of a node chain */
/**/
static void
pattail(long p, long val)
{
Upat scan, temp;
long offset;
scan = (Upat)patout + p;
for (;;) {
if (!(temp = PATNEXT(scan)))
break;
scan = temp;
}
offset = (P_OP(scan) == P_BACK)
? (scan - (Upat)patout) - val : val - (scan - (Upat)patout);
scan->l |= offset << 8;
}
/* do pattail, but on operand of first argument; nop if operandless */
/**/
static void patoptail(long p, long val)
{
Upat ptr = (Upat)patout + p;
int op = P_OP(ptr);
if (!p || !P_ISBRANCH(ptr))
return;
if (op == P_BRANCH)
pattail(P_OPERAND(p), val);
else
pattail(P_OPERAND(p) + 1, val);
}
/*
* Run a pattern.
*/
static char *patinstart; /* Start of input string */
/**/
char *patinput; /* String input pointer */
/* Length of input string, plus null byte, if needed */
static int patinlen;
/*
* Offset of string at which we are trying to match.
* This is added in to the positions recorded in patbeginp and patendp
* when we are looking for substrings. Currently this only happens
* in the parameter substitution code.
*/
/**/
int patoffset;
static char *patbeginp[NSUBEXP]; /* Pointer to backref beginnings */
static char *patendp[NSUBEXP]; /* Pointer to backref ends */
static int parsfound; /* parentheses (with backrefs) found */
static int globdots; /* Glob initial dots? */
/*
* The following need to be accessed in the globbing scanner for
* a multi-component file path. See horror story there.
*/
/**/
int errsfound; /* Total error count so far */
/**/
int forceerrs; /* Forced maximum error count */
/**/
void
pattrystart(void)
{
forceerrs = -1;
errsfound = 0;
}
/**/
mod_export int
pattry(Patprog prog, char *string)
{
return pattryrefs(prog, string, NULL, NULL, NULL);
}
/* The last three arguments are used to report the positions for the
* backreferences. On entry, *nump should contain the maximum number
* positions to report. */
/**/
mod_export int
pattryrefs(Patprog prog, char *string, int *nump, int *begp, int *endp)
{
int i, maxnpos = 0;
char **sp, **ep;
char *progstr = (char *)prog + prog->startoff;
if (nump) {
maxnpos = *nump;
*nump = 0;
}
/* inherited from domatch, but why, exactly? */
if (*string == Nularg)
string++;
patinstart = patinput = string;
if (prog->flags & (PAT_PURES|PAT_ANY)) {
if ((prog->flags & PAT_ANY) ||
((prog->flags & PAT_NOANCH) ?
!strncmp(progstr, string, prog->patmlen)
: !strcmp(progstr, string))) {
/* in case used for ${..#..} etc. */
patinput = string + prog->patmlen;
/* if matching files, must update globbing flags */
patglobflags = prog->globend;
return 1;
} else
return 0;
} else {
/*
* Test for a `must match' string, unless we're scanning for a match
* in which case we don't need to do this each time.
*/
if (!(prog->flags & PAT_SCAN) && prog->mustoff &&
!strstr(string, (char *)prog + prog->mustoff))
return 0;
patinlen = 0; /* don't calculate length unless needed */
patflags = prog->flags;
patglobflags = prog->globflags;
if (!(patflags & PAT_FILE)) {
forceerrs = -1;
errsfound = 0;
}
globdots = !(patflags & PAT_NOGLD);
parsfound = 0;
if (patmatch((Upat)progstr)) {
/*
* we were lazy and didn't save the globflags if an exclusion
* failed, so set it now
*/
patglobflags = prog->globend;
/*
* Should we clear backreferences and matches on a failed
* match?
*/
if ((patglobflags & GF_MATCHREF) && !(patflags & PAT_FILE)) {
/*
* m flag: for global match. This carries no overhead
* in the pattern matching part.
*/
char *str;
int mlen = ztrsub(patinput, patinstart);
str = ztrduppfx(patinstart, patinput - patinstart);
setsparam("MATCH", str);
setiparam("MBEGIN", (zlong)(patoffset + !isset(KSHARRAYS)));
setiparam("MEND",
(zlong)(mlen + patoffset + !isset(KSHARRAYS) - 1));
}
if (prog->patnpar && nump) {
/*
* b flag: for backreferences using parentheses. Reported
* directly.
*/
*nump = prog->patnpar;
sp = patbeginp;
ep = patendp;
for (i = 0; i < prog->patnpar && i < maxnpos; i++) {
if (parsfound & (1 << i)) {
if (begp)
*begp++ = ztrsub(*sp, patinstart) + patoffset;
if (endp)
*endp++ = ztrsub(*ep, patinstart) + patoffset - 1;
} else {
if (begp)
*begp++ = -1;
if (endp)
*endp++ = -1;
}
sp++;
ep++;
}
} else if (prog->patnpar && !(patflags & PAT_FILE)) {
/*
* b flag: for backreferences using parentheses.
*/
int palen = prog->patnpar+1;
char **matcharr, **mbeginarr, **mendarr;
char numbuf[DIGBUFSIZE];
matcharr = zcalloc(palen*sizeof(char *));
mbeginarr = zcalloc(palen*sizeof(char *));
mendarr = zcalloc(palen*sizeof(char *));
sp = patbeginp;
ep = patendp;
for (i = 0; i < prog->patnpar; i++) {
if (parsfound & (1 << i)) {
matcharr[i] = ztrduppfx(*sp, *ep - *sp);
/*
* mbegin and mend give indexes into the string
* in the standard notation, i.e. respecting
* KSHARRAYS, and with the end index giving
* the last character, not one beyond.
* For example, foo=foo; [[ $foo = (f)oo ]] gives
* (without KSHARRAYS) indexes 1 and 1, which
* corresponds to indexing as ${foo[1,1]}.
*/
sprintf(numbuf, "%ld",
(long)(ztrsub(*sp, patinstart) +
patoffset +
!isset(KSHARRAYS)));
mbeginarr[i] = ztrdup(numbuf);
sprintf(numbuf, "%ld",
(long)(ztrsub(*ep, patinstart) +
patoffset +
!isset(KSHARRAYS) - 1));
mendarr[i] = ztrdup(numbuf);
} else {
/* Pattern wasn't set: either it was in an
* unmatched branch, or a hashed parenthesis
* that didn't match at all.
*/
matcharr[i] = ztrdup("");
mbeginarr[i] = ztrdup("-1");
mendarr[i] = ztrdup("-1");
}
sp++;
ep++;
}
setaparam("match", matcharr);
setaparam("mbegin", mbeginarr);
setaparam("mend", mendarr);
}
return 1;
} else
return 0;
}
}
/*
* Match literal characters with case insensitivity test: the first
* comes from the input string, the second the current pattern.
*/
#define CHARMATCH(chin, chpa) (chin == chpa || \
((patglobflags & GF_IGNCASE) ? \
((isupper(chin) ? tolower(chin) : chin) == \
(isupper(chpa) ? tolower(chpa) : chpa)) : \
(patglobflags & GF_LCMATCHUC) ? \
(islower(chpa) && toupper(chpa) == chin) : 0))
/*
* exactpos is used to remember how far down an exact string we have
* matched, if we are doing approximation and can therefore redo from
* the same point; we never need to otherwise.
*/
static char *exactpos;
/*
* Main matching routine.
*
* Testing the tail end of a match is usually done by recursion, but
* we try to eliminate that in favour of looping for simple cases.
*/
/**/
static int
patmatch(Upat prog)
{
/* Current and next nodes */
Upat scan = prog, next, opnd;
char *start, *save, *chrop;
int savglobflags, op, no, min, nextch, fail = 0, saverrsfound;
zrange_t from, to, comp;
while (scan) {
next = PATNEXT(scan);
if (!globdots && P_NOTDOT(scan) && patinput == patinstart &&
*patinput == '.')
return 0;
switch (P_OP(scan)) {
case P_ANY:
if (!*patinput)
fail = 1;
else
METAINC(patinput);
break;
case P_EXACTLY:
/*
* acts as nothing if *chrop is null: this is used by
* approx code.
*/
chrop = exactpos ? exactpos : (char *)P_OPERAND(scan);
exactpos = NULL;
while (*chrop && *patinput) {
int chin = STOUC(UNMETA(patinput));
int chpa = STOUC(UNMETA(chrop));
if (!CHARMATCH(chin, chpa)) {
fail = 1;
break;
}
METAINC(chrop);
METAINC(patinput);
}
if (*chrop) {
exactpos = chrop;
fail = 1;
}
break;
case P_ANYOF:
if (!*patinput ||
!patmatchrange((char *)P_OPERAND(scan),
STOUC(UNMETA(patinput))))
fail = 1;
else
METAINC(patinput);
break;
case P_ANYBUT:
if (!*patinput ||
patmatchrange((char *)P_OPERAND(scan),
STOUC(UNMETA(patinput))))
fail = 1;
else
METAINC(patinput);
break;
case P_NUMRNG:
case P_NUMFROM:
case P_NUMTO:
/*
* To do this properly, we really have to treat numbers as
* closures: that's so things like like <1-1000>33 will
* match 633 (they didn't up to 3.1.6). To avoid making this
* too inefficient, we see if there's an exact match next:
* if there is, and it's not a digit, we return 1 after
* the first attempt.
*/
op = P_OP(scan);
start = (char *)P_OPERAND(scan);
from = to = 0;
if (op != P_NUMTO) {
#ifdef ZSH_64_BIT_TYPE
/* We can't rely on pointer alignment being good enough. */
memcpy((char *)&from, start, sizeof(zrange_t));
#else
from = *((zrange_t *) start);
#endif
start += sizeof(zrange_t);
}
if (op != P_NUMFROM) {
#ifdef ZSH_64_BIT_TYPE
memcpy((char *)&to, start, sizeof(zrange_t));
#else
to = *((zrange_t *) start);
#endif
}
start = patinput;
comp = (zrange_t) zstrtol(patinput, &save, 10);
patinput = save;
no = 0;
while (patinput > start) {
/* if already too small, no power on earth can save it */
if (comp < from)
break;
if ((op == P_NUMFROM || comp <= to) && patmatch(next)) {
return 1;
}
if (!no && P_OP(next) == P_EXACTLY &&
!idigit(STOUC(*(char *)P_OPERAND(next))) &&
!(patglobflags & 0xff))
return 0;
patinput = --save;
no++;
comp /= 10;
}
patinput = start;
fail = 1;
break;
case P_NUMANY:
/* This is <->: any old set of digits, don't bother comparing */
start = patinput;
while (idigit(STOUC(*patinput)))
patinput++;
save = patinput;
no = 0;
while (patinput > start) {
if (patmatch(next))
return 1;
if (!no && P_OP(next) == P_EXACTLY &&
!idigit(STOUC(*(char *)P_OPERAND(next))) &&
!(patglobflags & 0xff))
return 0;
patinput = --save;
no++;
}
patinput = start;
fail = 1;
break;
case P_NOTHING:
break;
case P_BACK:
break;
case P_GFLAGS:
patglobflags = P_OPERAND(scan)->l;
break;
case P_OPEN:
case P_OPEN+1:
case P_OPEN+2:
case P_OPEN+3:
case P_OPEN+4:
case P_OPEN+5:
case P_OPEN+6:
case P_OPEN+7:
case P_OPEN+8:
case P_OPEN+9:
no = P_OP(scan) - P_OPEN;
save = patinput;
if (patmatch(next)) {
/*
* Don't set patbeginp if some later invocation of
* the same parentheses already has.
*/
if (no && !(parsfound & (1 << (no - 1)))) {
patbeginp[no-1] = save;
parsfound |= 1 << (no - 1);
}
return 1;
} else
return 0;
break;
case P_CLOSE:
case P_CLOSE+1:
case P_CLOSE+2:
case P_CLOSE+3:
case P_CLOSE+4:
case P_CLOSE+5:
case P_CLOSE+6:
case P_CLOSE+7:
case P_CLOSE+8:
case P_CLOSE+9:
no = P_OP(scan) - P_CLOSE;
save = patinput;
if (patmatch(next)) {
DPUTS(!patendp, "patendp not set for backreferencing");
if (no && !(parsfound & (1 << (no + 15)))) {
patendp[no-1] = save;
parsfound |= 1 << (no + 15);
}
return 1;
} else
return 0;
break;
case P_EXCSYNC:
/* See the P_EXCLUDE code below for where syncptr comes from */
{
unsigned char *syncptr;
Upat after;
after = P_OPERAND(scan);
DPUTS(!P_ISEXCLUDE(after),
"BUG: EXCSYNC not followed by EXCLUDE.");
DPUTS(!P_OPERAND(after)->p,
"BUG: EXCSYNC not handled by EXCLUDE");
syncptr = P_OPERAND(after)->p + (patinput - patinstart);
/*
* If we already matched from here, this time we fail.
* See WBRANCH code for story about error count.
*/
if (*syncptr && errsfound + 1 >= *syncptr)
return 0;
/*
* Else record that we (possibly) matched this time.
* No harm if we don't: then the previous test will just
* short cut the attempted match that is bound to fail.
* We never try to exclude something that has already
* failed anyway.
*/
*syncptr = errsfound + 1;
}
break;
case P_EXCEND:
/*
* This is followed by a P_EXCSYNC, but only in the P_EXCLUDE
* branch. Actually, we don't bother following it: all we
* need to know is that we successfully matched so far up
* to the end of the asserted pattern; the endpoint
* in the target string is nulled out.
*/
if (!(fail = (*patinput != '\0')))
return 1;
break;
case P_BRANCH:
case P_WBRANCH:
/* P_EXCLUDE shouldn't occur without a P_BRANCH */
if (!P_ISBRANCH(next)) {
/* no choice, avoid recursion */
DPUTS(P_OP(scan) == P_WBRANCH,
"BUG: WBRANCH with no alternative.");
next = P_OPERAND(scan);
} else {
do {
save = patinput;
savglobflags = patglobflags;
saverrsfound = errsfound;
if (P_ISEXCLUDE(next)) {
/*
* The strategy is to test the asserted pattern,
* recording via P_EXCSYNC how far the part to
* be excluded matched. We then null out that
* point and see if the exclusion as far as
* P_EXCEND also matches that string.
* We need to keep testing the asserted pattern
* by backtracking, since the first attempt
* may be excluded while a later attempt may not.
* For this we keep a pointer just after
* the P_EXCLUDE which is tested by the P_EXCSYNC
* to see if we matched there last time, in which
* case we fail. If there is nothing to backtrack
* over, that doesn't matter: we should fail anyway.
* The pointer also tells us where the asserted
* pattern matched for use by the exclusion.
*/
Upat syncstrp;
unsigned char *oldsyncstr;
char *matchpt = NULL;
int ret, savglobdots, matchederrs = 0;
int savparsfound = parsfound;
DPUTS(P_OP(scan) == P_WBRANCH,
"BUG: excluded WBRANCH");
syncstrp = P_OPERAND(next);
/*
* Unlike WBRANCH, each test at the same exclude
* sync point (due to an external loop) is separate,
* i.e testing (foo~bar)# is no different from
* (foo~bar)(foo~bar)... from the exclusion point
* of view, so we use a different sync string.
*/
oldsyncstr = syncstrp->p;
if (!patinlen)
patinlen = strlen(patinstart)+1;
syncstrp->p = (unsigned char *)zcalloc(patinlen);
while ((ret = patmatch(P_OPERAND(scan)))) {
unsigned char *syncpt;
char savchar, *testptr;
char *savpatinstart = patinstart;
int savforce = forceerrs, savpatinlen = patinlen;
forceerrs = -1;
savglobdots = globdots;
matchederrs = errsfound;
matchpt = patinput; /* may not be end */
globdots = 1; /* OK to match . first */
/* Find the point where the scan
* matched the part to be excluded: because
* of backtracking, the one
* most recently matched will be the first.
* (Luckily, backtracking is done after all
* possibilities for approximation have been
* checked.)
*/
for (syncpt = syncstrp->p; !*syncpt; syncpt++)
;
testptr = patinstart + (syncpt - syncstrp->p);
DPUTS(testptr > matchpt, "BUG: EXCSYNC failed");
savchar = *testptr;
*testptr = '\0';
next = PATNEXT(scan);
while (next && P_ISEXCLUDE(next)) {
char *buf = NULL;
patinput = save;
/*
* turn off approximations in exclusions:
* note we keep remaining patglobflags
* set by asserted branch (or previous
* excluded branches, for consistency).
*/
patglobflags &= ~0xff;
errsfound = 0;
opnd = P_OPERAND(next) + 1;
if (P_OP(next) == P_EXCLUDP && pathpos) {
/*
* top level exclusion with a file,
* applies to whole path so add the
* segments already matched
*/
DPUTS(patinput != patinstart,
"BUG: not at start excluding path");
buf = (char *)
zalloc(pathpos + patinlen);
strcpy(buf, pathbuf);
strcpy(buf + pathpos, patinput);
patinput = patinstart = buf;
patinlen += pathpos;
}
if (patmatch(opnd)) {
ret = 0;
/*
* Another subtlety: if we exclude the
* match, any parentheses just found
* become invalidated.
*/
parsfound = savparsfound;
}
if (buf) {
patinstart = savpatinstart;
patinlen = savpatinlen;
zfree(buf, pathpos + patinlen);
}
if (!ret)
break;
next = PATNEXT(next);
}
*testptr = savchar;
globdots = savglobdots;
forceerrs = savforce;
if (ret)
break;
patinput = save;
patglobflags = savglobflags;
errsfound = saverrsfound;
}
zfree((char *)syncstrp->p, patinlen);
syncstrp->p = oldsyncstr;
if (ret) {
patinput = matchpt;
errsfound = matchederrs;
return 1;
}
while ((scan = PATNEXT(scan)) &&
P_ISEXCLUDE(scan))
;
} else {
int ret = 1, pfree = 0;
Upat ptrp = NULL;
unsigned char *ptr;
if (P_OP(scan) == P_WBRANCH) {
/*
* This is where we make sure that we are not
* repeatedly matching zero-length strings in
* a closure, which would cause an infinite loop,
* and also remove exponential behaviour in
* backtracking nested closures.
* The P_WBRANCH operator leaves a space for a
* uchar *, initialized to NULL, which is
* turned into a string the same length as the
* target string. Every time we match from a
* particular point in the target string, we
* stick a 1 at the corresponding point here.
* If we come round to the same branch again, and
* there is already a 1, then the test fails.
*/
opnd = P_OPERAND(scan);
ptrp = opnd++;
if (!ptrp->p) {
if (!patinlen)
patinlen = strlen((char *)patinstart)+1;
ptrp->p = (unsigned char *)zcalloc(patinlen);
pfree = 1;
}
ptr = ptrp->p + (patinput - patinstart);
/*
* Without approximation, this is just a
* single bit test. With approximation, we
* need to know how many errors there were
* last time we made the test. If errsfound
* is now smaller than it was, hence we can
* make more approximations in the remaining
* code, we continue with the test.
* (This is why the max number of errors is
* 254, not 255.)
*/
if (*ptr && errsfound + 1 >= *ptr)
ret = 0;
*ptr = errsfound + 1;
} else
opnd = P_OPERAND(scan);
if (ret)
ret = patmatch(opnd);
if (pfree) {
zfree((char *)ptrp->p, patinlen);
ptrp->p = NULL;
}
if (ret)
return 1;
scan = PATNEXT(scan);
}
patinput = save;
patglobflags = savglobflags;
errsfound = saverrsfound;
DPUTS(P_OP(scan) == P_WBRANCH,
"BUG: WBRANCH not first choice.");
next = PATNEXT(scan);
} while (scan && P_ISBRANCH(scan));
return 0;
}
break;
case P_STAR:
/* Handle specially for speed, although really P_ONEHASH+P_ANY */
case P_ONEHASH:
case P_TWOHASH:
/*
* This is just simple cases, matching one character.
* With approximations, we still handle * this way, since
* no approximation is ever necessary, but other closures
* are handled by the more compicated branching method
*/
op = P_OP(scan);
/* Note that no counts possibly metafied characters */
start = patinput;
if (op == P_STAR) {
for (no = 0; *patinput; METAINC(patinput))
no++;
/* simple optimization for reasonably common case */
if (P_OP(next) == P_END)
return 1;
} else {
DPUTS(patglobflags & 0xff,
"BUG: wrong backtracking with approximation.");
if (!globdots && P_NOTDOT(P_OPERAND(scan)) &&
patinput == patinstart && *patinput == '.')
return 0;
no = patrepeat(P_OPERAND(scan));
}
min = (op == P_TWOHASH) ? 1 : 0;
/*
* Lookahead to avoid useless matches. This is not possible
* with approximation.
*/
if (P_OP(next) == P_EXACTLY && !(patglobflags & 0xff)) {
char *nextop = (char *)P_OPERAND(next);
/*
* If that P_EXACTLY is last (common in simple patterns,
* such as *.c), then it can be only be matched at one
* point in the test string, so record that.
*/
if (P_OP(PATNEXT(next)) == P_END &&
!(patflags & PAT_NOANCH)) {
int ptlen = strlen(patinput);
int oplen = strlen(nextop);
/* Are we in the right range? */
if (oplen > strlen(min ? METANEXT(start) : start) ||
oplen < ptlen)
return 0;
/* Yes, just position appropriately and test. */
patinput += ptlen - oplen;
if (patinput > start && patinput[-1] == Meta) {
/* doesn't align properly, no go */
return 0;
}
/* Continue loop with P_EXACTLY test. */
break;
}
nextch = STOUC(UNMETA(nextop));
} else
nextch = -1;
save = patinput;
savglobflags = patglobflags;
saverrsfound = errsfound;
while (no >= min) {
int chin;
if ((nextch < 0 || (chin = STOUC(UNMETA(patinput)),
CHARMATCH(chin, nextch))) &&
patmatch(next))
return 1;
no--;
save--;
if (save > start && save[-1] == Meta)
save--;
patinput = save;
patglobflags = savglobflags;
errsfound = saverrsfound;
}
/*
* As with branches, the patmatch(next) stuff for *
* handles approximation, so we don't need to try
* anything here.
*/
return 0;
case P_ISSTART:
if (patinput != patinstart)
fail = 1;
break;
case P_ISEND:
if (*patinput)
fail = 1;
break;
case P_END:
if (!(fail = (*patinput && !(patflags & PAT_NOANCH))))
return 1;
break;
#ifdef DEBUG
default:
dputs("BUG: bad operand in patmatch.");
return 0;
break;
#endif
}
if (fail) {
if (errsfound < (patglobflags & 0xff) &&
(forceerrs == -1 || errsfound < forceerrs)) {
/*
* Approximation code. There are four possibilities
*
* 1. omit character from input string
* 2. transpose characters in input and pattern strings
* 3. omit character in both input and pattern strings
* 4. omit character from pattern string.
*
* which we try in that order.
*
* Of these, 2, 3 and 4 require an exact match string
* (P_EXACTLY) while 1, 2 and 3 require that we not
* have reached the end of the input string.
*
* Note in each case after making the approximation we
* need to retry the *same* pattern; this is what
* requires exactpos, a slightly doleful way of
* communicating with the exact character matcher.
*/
char *savexact = exactpos;
save = patinput;
savglobflags = patglobflags;
saverrsfound = ++errsfound;
fail = 0;
DPUTS(P_OP(scan) != P_EXACTLY && exactpos,
"BUG: non-exact match has set exactpos");
/* Try omitting a character from the input string */
if (*patinput) {
METAINC(patinput);
/* If we are not on an exact match, then this is
* our last gasp effort, so we can optimize out
* the recursive call.
*/
if (P_OP(scan) != P_EXACTLY)
continue;
if (patmatch(scan))
return 1;
}
if (P_OP(scan) == P_EXACTLY) {
char *nextexact = savexact;
DPUTS(!savexact || !*savexact,
"BUG: exact match has not set exactpos");
METAINC(nextexact);
if (*save) {
char *nextin = save;
METAINC(nextin);
patglobflags = savglobflags;
errsfound = saverrsfound;
exactpos = savexact;
/*
* Try swapping two characters in patinput and
* exactpos
*/
if (*save && *nextin && *nextexact) {
int cin0 = UNMETA(save);
int cpa0 = UNMETA(exactpos);
int cin1 = UNMETA(nextin);
int cpa1 = UNMETA(nextexact);
if (CHARMATCH(cin0, cpa1) &&
CHARMATCH(cin1, cpa0)) {
patinput = nextin;
METAINC(patinput);
exactpos = nextexact;
METAINC(exactpos);
if (patmatch(scan))
return 1;
patglobflags = savglobflags;
errsfound = saverrsfound;
}
}
/*
* Try moving up both strings.
*/
patinput = nextin;
exactpos = nextexact;
if (patmatch(scan))
return 1;
patinput = save;
patglobflags = savglobflags;
errsfound = saverrsfound;
exactpos = savexact;
}
/*
* Try moving up the exact match pattern.
* This must be the last attempt, so just loop
* instead of calling recursively.
*/
METAINC(exactpos);
continue;
}
}
exactpos = NULL;
return 0;
}
scan = next;
}
return 0;
}
/**/
static int
patmatchrange(char *range, int ch)
{
int r1, r2;
for (; *range; range++) {
if (imeta(STOUC(*range))) {
switch (STOUC(*range)-STOUC(Meta)) {
case 0:
if (STOUC(*++range ^ 32) == ch)
return 1;
break;
case PP_ALPHA:
if (isalpha(ch))
return 1;
break;
case PP_ALNUM:
if (isalnum(ch))
return 1;
break;
case PP_BLANK:
if (ch == ' ' || ch == '\t')
return 1;
break;
case PP_CNTRL:
if (iscntrl(ch))
return 1;
break;
case PP_DIGIT:
if (isdigit(ch))
return 1;
break;
case PP_GRAPH:
if (isgraph(ch))
return 1;
break;
case PP_LOWER:
if (islower(ch))
return 1;
break;
case PP_PRINT:
if (isprint(ch))
return 1;
break;
case PP_PUNCT:
if (ispunct(ch))
return 1;
break;
case PP_SPACE:
if (isspace(ch))
return 1;
break;
case PP_UPPER:
if (isupper(ch))
return 1;
break;
case PP_XDIGIT:
if (isxdigit(ch))
return 1;
case PP_RANGE:
range++;
r1 = STOUC(UNMETA(range));
METAINC(range);
r2 = STOUC(UNMETA(range));
if (*range == Meta)
range++;
if (r1 <= ch && ch <= r2)
return 1;
break;
case PP_UNKWN:
DPUTS(1, "BUG: unknown posix range passed through.\n");
break;
default:
DPUTS(1, "BUG: unknown metacharacter in range.");
break;
}
} else if (*range == ch)
return 1;
}
return 0;
}
/* repeatedly match something simple and say how many times */
/**/
static int patrepeat(Upat p)
{
int count = 0, tch, inch;
char *scan, *opnd;
scan = patinput;
opnd = (char *)P_OPERAND(p);
switch(P_OP(p)) {
#ifdef DEBUG
case P_ANY:
dputs("BUG: ?# did not get optimized to *");
return 0;
break;
#endif
case P_EXACTLY:
tch = STOUC(UNMETA(opnd));
while (*scan && (inch = STOUC(UNMETA(scan)), CHARMATCH(inch, tch))) {
count++;
METAINC(scan);
}
break;
case P_ANYOF:
while (*scan && patmatchrange(opnd, STOUC(UNMETA(scan)))) {
count++;
METAINC(scan);
}
break;
case P_ANYBUT:
while (*scan && !patmatchrange(opnd, STOUC(UNMETA(scan)))) {
count++;
METAINC(scan);
}
break;
#ifdef DEBUG
default:
dputs("BUG: something very strange is happening in patrepeat");
return 0;
break;
#endif
}
patinput = scan;
return count;
}
/* Free a patprog. */
/**/
mod_export void
freepatprog(Patprog prog)
{
if (prog && prog != dummy_patprog1 && prog != dummy_patprog2)
zfree(prog, prog->size);
}
/**/
#ifdef ZSH_PAT_DEBUG
/* Debugging stuff: print and test a regular expression */
/* Dump a regexp onto stdout in vaguely comprehensible form */
/**/
static void
patdump(Patprog r)
{
char *s, *base, op = P_EXACTLY;
Upat up, codestart, next;
base = (char *)r;
s = base + r->startoff;
if (r->flags & PAT_PURES) {
printf("STRING:%s\n", (char *)s);
} else {
codestart = (Upat)s;
while (op != P_END) {
up = (Upat)s;
op = P_OP(up);
printf("%2d%s", up-codestart, patprop(up));
next = PATNEXT(up);
printf("(%d)", next ? next-codestart : 0);
s += sizeof(union upat);
if (op == P_ANYOF || op == P_ANYBUT || op == P_EXACTLY) {
while (*s != '\0') {
if (itok(*s)) {
if (*s == Meta + PP_RANGE) {
s++;
printf("<RANGE:%c-", UNMETA(s));
METAINC(s);
printf("%c>", UNMETA(s));
} else {
printf("<TYPE:%d>", *s - Meta);
s++;
continue;
}
} else
putchar(UNMETA(s));
METAINC(s);
}
} else if (op == P_NUMRNG || op == P_NUMFROM || op == P_NUMTO) {
printf("%lu", (unsigned long)*(zrange_t *)s);
s += sizeof(zrange_t);
if (op == P_NUMRNG) {
printf("-%lu", (unsigned long)*(zrange_t *)s);
s += sizeof(zrange_t);
}
} else if (op == P_GFLAGS) {
printf("%ld, %ld", (++up)->l & ~0xff, (++up)->l & 0xff);
s += sizeof(union upat);
} else if (op == P_WBRANCH || op == P_EXCLUDE ||
op == P_EXCLUDP) {
s += sizeof(union upat);
}
putchar('\n');
s = base + (((s - base) + sizeof(union upat) - 1) &
~(sizeof(union upat) - 1));
}
}
printf("Total size = %ld\n", r->size);
if (r->patstartch)
printf("start `%c' ", r->patstartch);
if (!(r->flags & PAT_NOANCH))
printf("EOL-anchor ");
if (r->patnpar)
printf("%d active backreferences ", r->patnpar);
if (r->mustoff)
printf("must have \"%s\"", (char *)r + r->mustoff);
printf("\n");
if (r->globflags) {
printf("Globbing flags: ");
if (r->globflags & GF_LCMATCHUC)
printf("LC matches UC ");
if (r->globflags & GF_IGNCASE)
printf("Ignore case");
printf("\n");
if (r->globflags & 0xff)
printf("Max errors = %d\n", r->globflags & 0xff);
}
}
/**/
static char *
patprop(Upat op)
{
char *p = NULL;
static char buf[50];
strcpy(buf, ":");
switch(P_OP(op)) {
case P_ANY:
p = "ANY";
break;
case P_ANYOF:
p = "ANYOF";
break;
case P_ANYBUT:
p = "ANYBUT";
break;
case P_BRANCH:
p = "BRANCH";
break;
case P_WBRANCH:
p = "WBRANCH";
break;
case P_EXCLUDE:
p = "EXCLUDE";
break;
case P_EXCLUDP:
p = "EXCLUDP";
break;
case P_EXCSYNC:
p = "EXCSYNC";
break;
case P_EXCEND:
p = "EXCEND";
break;
case P_EXACTLY:
p = "EXACTLY";
break;
case P_GFLAGS:
p = "GFLAGS";
break;
case P_ISSTART:
p = "ISSTART";
break;
case P_ISEND:
p = "ISEND";
break;
case P_NOTHING:
p = "NOTHING";
break;
case P_BACK:
p = "BACK";
break;
case P_END:
p = "END";
break;
case P_OPEN:
case P_OPEN+1:
case P_OPEN+2:
case P_OPEN+3:
case P_OPEN+4:
case P_OPEN+5:
case P_OPEN+6:
case P_OPEN+7:
case P_OPEN+8:
case P_OPEN+9:
sprintf(buf+strlen(buf), "OPEN%ld", P_OP(op)-P_OPEN);
p = NULL;
break;
case P_CLOSE:
case P_CLOSE+1:
case P_CLOSE+2:
case P_CLOSE+3:
case P_CLOSE+4:
case P_CLOSE+5:
case P_CLOSE+6:
case P_CLOSE+7:
case P_CLOSE+8:
case P_CLOSE+9:
sprintf(buf+strlen(buf), "CLOSE%ld", P_OP(op)-P_CLOSE);
p = NULL;
break;
case P_STAR:
p = "STAR";
break;
case P_ONEHASH:
p = "ONEHASH";
break;
case P_TWOHASH:
p = "TWOHASH";
break;
case P_NUMRNG:
p = "NUMRNG";
break;
case P_NUMFROM:
p = "NUMFROM";
break;
case P_NUMTO:
p = "NUMTO";
break;
case P_NUMANY:
p = "NUMANY";
break;
default:
fprintf(stderr, "Bad opcode\n");
p = NULL;
break;
}
if (p)
strcat(buf, p);
return buf;
}
/**/
int
bin_patdebug(char *name, char **args, char *ops, int func)
{
Patprog prog;
int ret = 0;
tokenize(*args);
if (!(prog = patcompile((char *)*args, 0, 0)))
return 1;
if (ops['p'] || !args[1]) {
patdump(prog);
}
while (*++args) {
if (!pattry(prog, (char *)*args))
ret++;
}
return ret;
}
/**/
#endif /* ZSH_PAT_DEBUG */
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