NetBSD/bin/sh/expand.c
kre f359a311bc Arrange for set -o and $- output to be sorted, rather than more
or less random (and becoming worse as more options are added.)
Since the data is known at compile time, sort at compile time,
rather than at run time.
2017-05-28 00:38:01 +00:00

1690 lines
34 KiB
C

/* $NetBSD: expand.c,v 1.106 2017/05/28 00:38:01 kre Exp $ */
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95";
#else
__RCSID("$NetBSD: expand.c,v 1.106 2017/05/28 00:38:01 kre Exp $");
#endif
#endif /* not lint */
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <errno.h>
#include <dirent.h>
#include <unistd.h>
#include <pwd.h>
#include <limits.h>
#include <stdlib.h>
#include <stdio.h>
#include <wctype.h>
#include <wchar.h>
/*
* Routines to expand arguments to commands. We have to deal with
* backquotes, shell variables, and file metacharacters.
*/
#include "shell.h"
#include "main.h"
#include "nodes.h"
#include "eval.h"
#include "expand.h"
#include "syntax.h"
#include "arithmetic.h"
#include "parser.h"
#include "jobs.h"
#include "options.h"
#include "builtins.h"
#include "var.h"
#include "input.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "mystring.h"
#include "show.h"
/*
* Structure specifying which parts of the string should be searched
* for IFS characters.
*/
struct ifsregion {
struct ifsregion *next; /* next region in list */
int begoff; /* offset of start of region */
int endoff; /* offset of end of region */
int inquotes; /* search for nul bytes only */
};
char *expdest; /* output of current string */
struct nodelist *argbackq; /* list of back quote expressions */
struct ifsregion ifsfirst; /* first struct in list of ifs regions */
struct ifsregion *ifslastp; /* last struct in list */
struct arglist exparg; /* holds expanded arg list */
STATIC void argstr(char *, int);
STATIC char *exptilde(char *, int);
STATIC void expbackq(union node *, int, int);
STATIC int subevalvar(char *, char *, int, int, int, int, int);
STATIC char *evalvar(char *, int);
STATIC int varisset(char *, int);
STATIC void varvalue(char *, int, int, int);
STATIC void recordregion(int, int, int);
STATIC void removerecordregions(int);
STATIC void ifsbreakup(char *, struct arglist *);
STATIC void ifsfree(void);
STATIC void expandmeta(struct strlist *, int);
STATIC void expmeta(char *, char *);
STATIC void addfname(char *);
STATIC struct strlist *expsort(struct strlist *);
STATIC struct strlist *msort(struct strlist *, int);
STATIC int patmatch(const char *, const char *, int);
STATIC char *cvtnum(int, char *);
static int collate_range_cmp(wchar_t, wchar_t);
/*
* Expand shell variables and backquotes inside a here document.
*/
void
expandhere(union node *arg, int fd)
{
herefd = fd;
expandarg(arg, NULL, 0);
xwrite(fd, stackblock(), expdest - stackblock());
}
static int
collate_range_cmp(wchar_t c1, wchar_t c2)
{
wchar_t s1[2], s2[2];
s1[0] = c1;
s1[1] = L'\0';
s2[0] = c2;
s2[1] = L'\0';
return (wcscoll(s1, s2));
}
/*
* Perform variable substitution and command substitution on an argument,
* placing the resulting list of arguments in arglist. If EXP_FULL is true,
* perform splitting and file name expansion. When arglist is NULL, perform
* here document expansion.
*/
void
expandarg(union node *arg, struct arglist *arglist, int flag)
{
struct strlist *sp;
char *p;
argbackq = arg->narg.backquote;
STARTSTACKSTR(expdest);
ifsfirst.next = NULL;
ifslastp = NULL;
argstr(arg->narg.text, flag);
if (arglist == NULL) {
return; /* here document expanded */
}
STPUTC('\0', expdest);
p = grabstackstr(expdest);
exparg.lastp = &exparg.list;
/*
* TODO - EXP_REDIR
*/
if (flag & EXP_FULL) {
ifsbreakup(p, &exparg);
*exparg.lastp = NULL;
exparg.lastp = &exparg.list;
expandmeta(exparg.list, flag);
} else {
if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
rmescapes(p);
sp = stalloc(sizeof(*sp));
sp->text = p;
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
ifsfree();
*exparg.lastp = NULL;
if (exparg.list) {
*arglist->lastp = exparg.list;
arglist->lastp = exparg.lastp;
}
}
/*
* Perform variable and command substitution.
* If EXP_FULL is set, output CTLESC characters to allow for further processing.
* Otherwise treat $@ like $* since no splitting will be performed.
*/
STATIC void
argstr(char *p, int flag)
{
char c;
int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */
int firsteq = 1;
const char *ifs = NULL;
int ifs_split = EXP_IFS_SPLIT;
if (flag & EXP_IFS_SPLIT)
ifs = ifsval();
if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
p = exptilde(p, flag);
for (;;) {
switch (c = *p++) {
case '\0':
case CTLENDVAR: /* end of expanding yyy in ${xxx-yyy} */
return;
case CTLQUOTEMARK:
/* "$@" syntax adherence hack */
if (p[0] == CTLVAR && p[1] & VSQUOTE &&
p[2] == '@' && p[3] == '=')
break;
if ((flag & EXP_FULL) != 0)
STPUTC(c, expdest);
ifs_split = 0;
break;
case CTLQUOTEEND:
ifs_split = EXP_IFS_SPLIT;
break;
case CTLESC:
if (quotes)
STPUTC(c, expdest);
c = *p++;
STPUTC(c, expdest);
break;
case CTLVAR:
p = evalvar(p, (flag & ~EXP_IFS_SPLIT) | (flag & ifs_split));
break;
case CTLBACKQ:
case CTLBACKQ|CTLQUOTE:
expbackq(argbackq->n, c & CTLQUOTE, flag);
argbackq = argbackq->next;
break;
case CTLENDARI:
expari(flag);
break;
case ':':
case '=':
/*
* sort of a hack - expand tildes in variable
* assignments (after the first '=' and after ':'s).
*/
STPUTC(c, expdest);
if (flag & EXP_VARTILDE && *p == '~') {
if (c == '=') {
if (firsteq)
firsteq = 0;
else
break;
}
p = exptilde(p, flag);
}
break;
default:
STPUTC(c, expdest);
if (flag & ifs_split && strchr(ifs, c) != NULL) {
/* We need to get the output split here... */
recordregion(expdest - stackblock() - 1,
expdest - stackblock(), 0);
}
break;
}
}
}
STATIC char *
exptilde(char *p, int flag)
{
char c, *startp = p;
struct passwd *pw;
const char *home;
int quotes = flag & (EXP_FULL | EXP_CASE);
while ((c = *p) != '\0') {
switch(c) {
case CTLESC:
return (startp);
case CTLQUOTEMARK:
return (startp);
case ':':
if (flag & EXP_VARTILDE)
goto done;
break;
case '/':
goto done;
}
p++;
}
done:
*p = '\0';
if (*(startp+1) == '\0') {
if ((home = lookupvar("HOME")) == NULL)
goto lose;
} else {
if ((pw = getpwnam(startp+1)) == NULL)
goto lose;
home = pw->pw_dir;
}
if (*home == '\0')
goto lose;
*p = c;
while ((c = *home++) != '\0') {
if (quotes && SQSYNTAX[(int)c] == CCTL)
STPUTC(CTLESC, expdest);
STPUTC(c, expdest);
}
return (p);
lose:
*p = c;
return (startp);
}
STATIC void
removerecordregions(int endoff)
{
if (ifslastp == NULL)
return;
if (ifsfirst.endoff > endoff) {
while (ifsfirst.next != NULL) {
struct ifsregion *ifsp;
INTOFF;
ifsp = ifsfirst.next->next;
ckfree(ifsfirst.next);
ifsfirst.next = ifsp;
INTON;
}
if (ifsfirst.begoff > endoff)
ifslastp = NULL;
else {
ifslastp = &ifsfirst;
ifsfirst.endoff = endoff;
}
return;
}
ifslastp = &ifsfirst;
while (ifslastp->next && ifslastp->next->begoff < endoff)
ifslastp=ifslastp->next;
while (ifslastp->next != NULL) {
struct ifsregion *ifsp;
INTOFF;
ifsp = ifslastp->next->next;
ckfree(ifslastp->next);
ifslastp->next = ifsp;
INTON;
}
if (ifslastp->endoff > endoff)
ifslastp->endoff = endoff;
}
/*
* Expand arithmetic expression. Backup to start of expression,
* evaluate, place result in (backed up) result, adjust string position.
*/
void
expari(int flag)
{
char *p, *q, *start;
intmax_t result;
int adjustment;
int begoff;
int quotes = flag & (EXP_FULL | EXP_CASE);
int quoted;
/* ifsfree(); */
/*
* This routine is slightly over-complicated for
* efficiency. First we make sure there is
* enough space for the result, which may be bigger
* than the expression if we add exponentation. Next we
* scan backwards looking for the start of arithmetic. If the
* next previous character is a CTLESC character, then we
* have to rescan starting from the beginning since CTLESC
* characters have to be processed left to right.
*/
/*
* SPACE_NEEDED is enough for all possible digits (rounded up)
* plus possible "-", and the terminating '\0', hence, plus 2
*
* The calculation produces the number of bytes needed to
* represent the biggest possible value, in octal. We only
* generate decimal, which takes (often) less digits (never more)
* so this is safe, if occasionally slightly wasteful.
*/
#define SPACE_NEEDED ((sizeof(intmax_t) * CHAR_BIT + 2) / 3 + 2)
/*
* Only need check for SPACE_NEEDED-2 as we have already
* consumed (but will overwrite) 2 chars, the CTLARI, and the
* flags (quoting) byte (if those had not already been seen,
* we would not be here.)
*/
CHECKSTRSPACE((int)(SPACE_NEEDED - 2), expdest);
USTPUTC('\0', expdest);
start = stackblock();
p = expdest - 1;
while (*p != CTLARI && p >= start)
--p;
if (*p != CTLARI)
error("missing CTLARI (shouldn't happen)");
if (p > start && *(p-1) == CTLESC)
for (p = start; *p != CTLARI; p++)
if (*p == CTLESC)
p++;
if (p[1] == '"')
quoted=1;
else
quoted=0;
begoff = p - start;
removerecordregions(begoff);
if (quotes)
rmescapes(p+2);
q = grabstackstr(expdest);
result = arith(p+2);
ungrabstackstr(q, expdest);
fmtstr(p, SPACE_NEEDED, "%"PRIdMAX, result);
while (*p++)
;
if (quoted == 0)
recordregion(begoff, p - 1 - start, 0);
adjustment = expdest - p + 1;
STADJUST(-adjustment, expdest);
}
/*
* Expand stuff in backwards quotes.
*/
STATIC void
expbackq(union node *cmd, int quoted, int flag)
{
struct backcmd in;
int i;
char buf[128];
char *p;
char *dest = expdest;
struct ifsregion saveifs, *savelastp;
struct nodelist *saveargbackq;
char lastc;
int startloc = dest - stackblock();
char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
int saveherefd;
int quotes = flag & (EXP_FULL | EXP_CASE);
int nnl;
INTOFF;
saveifs = ifsfirst;
savelastp = ifslastp;
saveargbackq = argbackq;
saveherefd = herefd;
herefd = -1;
p = grabstackstr(dest);
evalbackcmd(cmd, &in);
ungrabstackstr(p, dest);
ifsfirst = saveifs;
ifslastp = savelastp;
argbackq = saveargbackq;
herefd = saveherefd;
p = in.buf;
lastc = '\0';
nnl = 0;
for (;;) {
if (--in.nleft < 0) {
if (in.fd < 0)
break;
while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR)
continue;
TRACE(("expbackq: read returns %d\n", i));
if (i <= 0)
break;
p = buf;
in.nleft = i - 1;
}
lastc = *p++;
if (lastc != '\0') {
if (lastc == '\n')
nnl++;
else {
CHECKSTRSPACE(nnl + 2, dest);
while (nnl > 0) {
nnl--;
USTPUTC('\n', dest);
}
if (quotes && syntax[(int)lastc] == CCTL)
USTPUTC(CTLESC, dest);
USTPUTC(lastc, dest);
}
}
}
if (in.fd >= 0)
close(in.fd);
if (in.buf)
ckfree(in.buf);
if (in.jp)
back_exitstatus = waitforjob(in.jp);
if (quoted == 0)
recordregion(startloc, dest - stackblock(), 0);
TRACE(("evalbackq: size=%d: \"%.*s\"\n",
(int)((dest - stackblock()) - startloc),
(int)((dest - stackblock()) - startloc),
stackblock() + startloc));
expdest = dest;
INTON;
}
STATIC int
subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varflags, int quotes)
{
char *startp;
char *loc = NULL;
char *q;
int c = 0;
int saveherefd = herefd;
struct nodelist *saveargbackq = argbackq;
int amount, how;
herefd = -1;
switch (subtype) {
case VSTRIMLEFT:
case VSTRIMLEFTMAX:
case VSTRIMRIGHT:
case VSTRIMRIGHTMAX:
how = (varflags & (VSQUOTE|VSPATQ)) == VSQUOTE ? 0 : EXP_CASE;
break;
default:
how = 0;
break;
}
argstr(p, how);
STACKSTRNUL(expdest);
herefd = saveherefd;
argbackq = saveargbackq;
startp = stackblock() + startloc;
if (str == NULL)
str = stackblock() + strloc;
switch (subtype) {
case VSASSIGN:
setvar(str, startp, 0);
amount = startp - expdest;
STADJUST(amount, expdest);
varflags &= ~VSNUL;
return 1;
case VSQUESTION:
if (*p != CTLENDVAR) {
outfmt(&errout, "%s\n", startp);
error(NULL);
}
error("%.*s: parameter %snot set",
(int)(p - str - 1),
str, (varflags & VSNUL) ? "null or "
: nullstr);
/* NOTREACHED */
case VSTRIMLEFT:
for (loc = startp; loc < str; loc++) {
c = *loc;
*loc = '\0';
if (patmatch(str, startp, quotes))
goto recordleft;
*loc = c;
if (quotes && *loc == CTLESC)
loc++;
}
return 0;
case VSTRIMLEFTMAX:
for (loc = str - 1; loc >= startp;) {
c = *loc;
*loc = '\0';
if (patmatch(str, startp, quotes))
goto recordleft;
*loc = c;
loc--;
if (quotes && loc > startp &&
*(loc - 1) == CTLESC) {
for (q = startp; q < loc; q++)
if (*q == CTLESC)
q++;
if (q > loc)
loc--;
}
}
return 0;
case VSTRIMRIGHT:
for (loc = str - 1; loc >= startp;) {
if (patmatch(str, loc, quotes))
goto recordright;
loc--;
if (quotes && loc > startp &&
*(loc - 1) == CTLESC) {
for (q = startp; q < loc; q++)
if (*q == CTLESC)
q++;
if (q > loc)
loc--;
}
}
return 0;
case VSTRIMRIGHTMAX:
for (loc = startp; loc < str - 1; loc++) {
if (patmatch(str, loc, quotes))
goto recordright;
if (quotes && *loc == CTLESC)
loc++;
}
return 0;
default:
abort();
}
recordleft:
*loc = c;
amount = ((str - 1) - (loc - startp)) - expdest;
STADJUST(amount, expdest);
while (loc != str - 1)
*startp++ = *loc++;
return 1;
recordright:
amount = loc - expdest;
STADJUST(amount, expdest);
STPUTC('\0', expdest);
STADJUST(-1, expdest);
return 1;
}
/*
* Expand a variable, and return a pointer to the next character in the
* input string.
*/
STATIC char *
evalvar(char *p, int flag)
{
int subtype;
int varflags;
char *var;
char *val;
int patloc;
int c;
int set;
int special;
int startloc;
int varlen;
int apply_ifs;
int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
varflags = (unsigned char)*p++;
subtype = varflags & VSTYPE;
var = p;
special = !is_name(*p);
p = strchr(p, '=') + 1;
again: /* jump here after setting a variable with ${var=text} */
if (varflags & VSLINENO) {
set = 1;
special = 0;
val = var;
p[-1] = '\0';
} else if (special) {
set = varisset(var, varflags & VSNUL);
val = NULL;
} else {
val = lookupvar(var);
if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
val = NULL;
set = 0;
} else
set = 1;
}
varlen = 0;
startloc = expdest - stackblock();
if (!set && uflag && *var != '@' && *var != '*') {
switch (subtype) {
case VSNORMAL:
case VSTRIMLEFT:
case VSTRIMLEFTMAX:
case VSTRIMRIGHT:
case VSTRIMRIGHTMAX:
case VSLENGTH:
error("%.*s: parameter not set",
(int)(p - var - 1), var);
/* NOTREACHED */
}
}
if (set && subtype != VSPLUS) {
/* insert the value of the variable */
if (special) {
varvalue(var, varflags & VSQUOTE, subtype, flag);
if (subtype == VSLENGTH) {
varlen = expdest - stackblock() - startloc;
STADJUST(-varlen, expdest);
}
} else {
char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
: BASESYNTAX;
if (subtype == VSLENGTH) {
for (;*val; val++)
varlen++;
} else {
while (*val) {
if (quotes && syntax[(int)*val] == CCTL)
STPUTC(CTLESC, expdest);
STPUTC(*val++, expdest);
}
}
}
}
if (flag & EXP_IN_QUOTES)
apply_ifs = 0;
else if (varflags & VSQUOTE) {
if (*var == '@' && shellparam.nparam != 1)
apply_ifs = 1;
else {
/*
* Mark so that we don't apply IFS if we recurse through
* here expanding $bar from "${foo-$bar}".
*/
flag |= EXP_IN_QUOTES;
apply_ifs = 0;
}
} else
apply_ifs = 1;
switch (subtype) {
case VSLENGTH:
expdest = cvtnum(varlen, expdest);
break;
case VSNORMAL:
break;
case VSPLUS:
set = !set;
/* FALLTHROUGH */
case VSMINUS:
if (!set) {
argstr(p, flag | (apply_ifs ? EXP_IFS_SPLIT : 0));
/*
* ${x-a b c} doesn't get split, but removing the
* 'apply_ifs = 0' apparently breaks ${1+"$@"}..
* ${x-'a b' c} should generate 2 args.
*/
if (*p != CTLENDVAR)
/* We should have marked stuff already */
apply_ifs = 0;
}
break;
case VSTRIMLEFT:
case VSTRIMLEFTMAX:
case VSTRIMRIGHT:
case VSTRIMRIGHTMAX:
if (!set) {
set = 1; /* allow argbackq to be advanced if needed */
break;
}
/*
* Terminate the string and start recording the pattern
* right after it
*/
STPUTC('\0', expdest);
patloc = expdest - stackblock();
if (subevalvar(p, NULL, patloc, subtype,
startloc, varflags, quotes) == 0) {
int amount = (expdest - stackblock() - patloc) + 1;
STADJUST(-amount, expdest);
}
/* Remove any recorded regions beyond start of variable */
removerecordregions(startloc);
apply_ifs = 1;
break;
case VSASSIGN:
case VSQUESTION:
if (set)
break;
if (subevalvar(p, var, 0, subtype, startloc, varflags, quotes)) {
varflags &= ~VSNUL;
/*
* Remove any recorded regions beyond
* start of variable
*/
removerecordregions(startloc);
goto again;
}
apply_ifs = 0;
break;
default:
abort();
}
p[-1] = '='; /* recover overwritten '=' */
if (apply_ifs)
recordregion(startloc, expdest - stackblock(),
varflags & VSQUOTE);
if (subtype != VSNORMAL) { /* skip to end of alternative */
int nesting = 1;
for (;;) {
if ((c = *p++) == CTLESC)
p++;
else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
if (set)
argbackq = argbackq->next;
} else if (c == CTLVAR) {
if ((*p++ & VSTYPE) != VSNORMAL)
nesting++;
} else if (c == CTLENDVAR) {
if (--nesting == 0)
break;
}
}
}
return p;
}
/*
* Test whether a specialized variable is set.
*/
STATIC int
varisset(char *name, int nulok)
{
if (*name == '!')
return backgndpid != -1;
else if (*name == '@' || *name == '*') {
if (*shellparam.p == NULL)
return 0;
if (nulok) {
char **av;
for (av = shellparam.p; *av; av++)
if (**av != '\0')
return 1;
return 0;
}
} else if (is_digit(*name)) {
char *ap;
int num = atoi(name);
if (num > shellparam.nparam)
return 0;
if (num == 0)
ap = arg0;
else
ap = shellparam.p[num - 1];
if (nulok && (ap == NULL || *ap == '\0'))
return 0;
}
return 1;
}
/*
* Add the value of a specialized variable to the stack string.
*/
STATIC void
varvalue(char *name, int quoted, int subtype, int flag)
{
int num;
char *p;
int i;
char sep;
char **ap;
char const *syntax;
#define STRTODEST(p) \
do {\
if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \
syntax = quoted? DQSYNTAX : BASESYNTAX; \
while (*p) { \
if (syntax[(int)*p] == CCTL) \
STPUTC(CTLESC, expdest); \
STPUTC(*p++, expdest); \
} \
} else \
while (*p) \
STPUTC(*p++, expdest); \
} while (0)
switch (*name) {
case '$':
num = rootpid;
goto numvar;
case '?':
num = exitstatus;
goto numvar;
case '#':
num = shellparam.nparam;
goto numvar;
case '!':
num = backgndpid;
numvar:
expdest = cvtnum(num, expdest);
break;
case '-':
for (i = 0; i < option_flags; i++) {
if (optlist[optorder[i]].val)
STPUTC(optlist[optorder[i]].letter, expdest);
}
break;
case '@':
if (flag & EXP_FULL && quoted) {
for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
STRTODEST(p);
if (*ap)
/* A NUL separates args inside "" */
STPUTC('\0', expdest);
}
break;
}
/* fall through */
case '*':
sep = ifsval()[0];
for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
STRTODEST(p);
if (!*ap)
break;
if (sep)
STPUTC(sep, expdest);
else if ((flag & (EXP_FULL|EXP_IN_QUOTES)) == EXP_FULL
&& !quoted && **ap != '\0')
STPUTC('\0', expdest);
}
break;
case '0':
p = arg0;
STRTODEST(p);
break;
default:
if (is_digit(*name)) {
num = atoi(name);
if (num > 0 && num <= shellparam.nparam) {
p = shellparam.p[num - 1];
STRTODEST(p);
}
}
break;
}
}
/*
* Record the fact that we have to scan this region of the
* string for IFS characters.
*/
STATIC void
recordregion(int start, int end, int inquotes)
{
struct ifsregion *ifsp;
if (ifslastp == NULL) {
ifsp = &ifsfirst;
} else {
if (ifslastp->endoff == start
&& ifslastp->inquotes == inquotes) {
/* extend previous area */
ifslastp->endoff = end;
return;
}
ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
ifslastp->next = ifsp;
}
ifslastp = ifsp;
ifslastp->next = NULL;
ifslastp->begoff = start;
ifslastp->endoff = end;
ifslastp->inquotes = inquotes;
}
/*
* Break the argument string into pieces based upon IFS and add the
* strings to the argument list. The regions of the string to be
* searched for IFS characters have been stored by recordregion.
*/
STATIC void
ifsbreakup(char *string, struct arglist *arglist)
{
struct ifsregion *ifsp;
struct strlist *sp;
char *start;
char *p;
char *q;
const char *ifs;
const char *ifsspc;
int had_param_ch = 0;
start = string;
if (ifslastp == NULL) {
/* Return entire argument, IFS doesn't apply to any of it */
sp = stalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
return;
}
ifs = ifsval();
for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
p = string + ifsp->begoff;
while (p < string + ifsp->endoff) {
had_param_ch = 1;
q = p;
if (*p == CTLESC)
p++;
if (ifsp->inquotes) {
/* Only NULs (should be from "$@") end args */
if (*p != 0) {
p++;
continue;
}
ifsspc = NULL;
} else {
if (!strchr(ifs, *p)) {
p++;
continue;
}
had_param_ch = 0;
ifsspc = strchr(" \t\n", *p);
/* Ignore IFS whitespace at start */
if (q == start && ifsspc != NULL) {
p++;
start = p;
continue;
}
}
/* Save this argument... */
*q = '\0';
sp = stalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
p++;
if (ifsspc != NULL) {
/* Ignore further trailing IFS whitespace */
for (; p < string + ifsp->endoff; p++) {
q = p;
if (*p == CTLESC)
p++;
if (strchr(ifs, *p) == NULL) {
p = q;
break;
}
if (strchr(" \t\n", *p) == NULL) {
p++;
break;
}
}
}
start = p;
}
}
/*
* Save anything left as an argument.
* Traditionally we have treated 'IFS=':'; set -- x$IFS' as
* generating 2 arguments, the second of which is empty.
* Some recent clarification of the Posix spec say that it
* should only generate one....
*/
if (had_param_ch || *start != 0) {
sp = stalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
}
}
STATIC void
ifsfree(void)
{
while (ifsfirst.next != NULL) {
struct ifsregion *ifsp;
INTOFF;
ifsp = ifsfirst.next->next;
ckfree(ifsfirst.next);
ifsfirst.next = ifsp;
INTON;
}
ifslastp = NULL;
ifsfirst.next = NULL;
}
/*
* Expand shell metacharacters. At this point, the only control characters
* should be escapes. The results are stored in the list exparg.
*/
char *expdir;
STATIC void
expandmeta(struct strlist *str, int flag)
{
char *p;
struct strlist **savelastp;
struct strlist *sp;
char c;
/* TODO - EXP_REDIR */
while (str) {
if (fflag)
goto nometa;
p = str->text;
for (;;) { /* fast check for meta chars */
if ((c = *p++) == '\0')
goto nometa;
if (c == '*' || c == '?' || c == '[' || c == '!')
break;
}
savelastp = exparg.lastp;
INTOFF;
if (expdir == NULL) {
int i = strlen(str->text);
expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */
}
expmeta(expdir, str->text);
ckfree(expdir);
expdir = NULL;
INTON;
if (exparg.lastp == savelastp) {
/*
* no matches
*/
nometa:
*exparg.lastp = str;
rmescapes(str->text);
exparg.lastp = &str->next;
} else {
*exparg.lastp = NULL;
*savelastp = sp = expsort(*savelastp);
while (sp->next != NULL)
sp = sp->next;
exparg.lastp = &sp->next;
}
str = str->next;
}
}
/*
* Do metacharacter (i.e. *, ?, [...]) expansion.
*/
STATIC void
expmeta(char *enddir, char *name)
{
char *p;
const char *cp;
char *q;
char *start;
char *endname;
int metaflag;
struct stat statb;
DIR *dirp;
struct dirent *dp;
int atend;
int matchdot;
metaflag = 0;
start = name;
for (p = name ; ; p++) {
if (*p == '*' || *p == '?')
metaflag = 1;
else if (*p == '[') {
q = p + 1;
if (*q == '!')
q++;
for (;;) {
while (*q == CTLQUOTEMARK)
q++;
if (*q == CTLESC)
q++;
if (*q == '/' || *q == '\0')
break;
if (*++q == ']') {
metaflag = 1;
break;
}
}
} else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) {
metaflag = 1;
} else if (*p == '\0')
break;
else if (*p == CTLQUOTEMARK)
continue;
else if (*p == CTLESC)
p++;
if (*p == '/') {
if (metaflag)
break;
start = p + 1;
}
}
if (metaflag == 0) { /* we've reached the end of the file name */
if (enddir != expdir)
metaflag++;
for (p = name ; ; p++) {
if (*p == CTLQUOTEMARK)
continue;
if (*p == CTLESC)
p++;
*enddir++ = *p;
if (*p == '\0')
break;
}
if (metaflag == 0 || lstat(expdir, &statb) >= 0)
addfname(expdir);
return;
}
endname = p;
if (start != name) {
p = name;
while (p < start) {
while (*p == CTLQUOTEMARK)
p++;
if (*p == CTLESC)
p++;
*enddir++ = *p++;
}
}
if (enddir == expdir) {
cp = ".";
} else if (enddir == expdir + 1 && *expdir == '/') {
cp = "/";
} else {
cp = expdir;
enddir[-1] = '\0';
}
if ((dirp = opendir(cp)) == NULL)
return;
if (enddir != expdir)
enddir[-1] = '/';
if (*endname == 0) {
atend = 1;
} else {
atend = 0;
*endname++ = '\0';
}
matchdot = 0;
p = start;
while (*p == CTLQUOTEMARK)
p++;
if (*p == CTLESC)
p++;
if (*p == '.')
matchdot++;
while (! int_pending() && (dp = readdir(dirp)) != NULL) {
if (dp->d_name[0] == '.' && ! matchdot)
continue;
if (patmatch(start, dp->d_name, 0)) {
if (atend) {
scopy(dp->d_name, enddir);
addfname(expdir);
} else {
for (p = enddir, cp = dp->d_name;
(*p++ = *cp++) != '\0';)
continue;
p[-1] = '/';
expmeta(p, endname);
}
}
}
closedir(dirp);
if (! atend)
endname[-1] = '/';
}
/*
* Add a file name to the list.
*/
STATIC void
addfname(char *name)
{
char *p;
struct strlist *sp;
p = stalloc(strlen(name) + 1);
scopy(name, p);
sp = stalloc(sizeof(*sp));
sp->text = p;
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
/*
* Sort the results of file name expansion. It calculates the number of
* strings to sort and then calls msort (short for merge sort) to do the
* work.
*/
STATIC struct strlist *
expsort(struct strlist *str)
{
int len;
struct strlist *sp;
len = 0;
for (sp = str ; sp ; sp = sp->next)
len++;
return msort(str, len);
}
STATIC struct strlist *
msort(struct strlist *list, int len)
{
struct strlist *p, *q = NULL;
struct strlist **lpp;
int half;
int n;
if (len <= 1)
return list;
half = len >> 1;
p = list;
for (n = half ; --n >= 0 ; ) {
q = p;
p = p->next;
}
q->next = NULL; /* terminate first half of list */
q = msort(list, half); /* sort first half of list */
p = msort(p, len - half); /* sort second half */
lpp = &list;
for (;;) {
if (strcmp(p->text, q->text) < 0) {
*lpp = p;
lpp = &p->next;
if ((p = *lpp) == NULL) {
*lpp = q;
break;
}
} else {
*lpp = q;
lpp = &q->next;
if ((q = *lpp) == NULL) {
*lpp = p;
break;
}
}
}
return list;
}
/*
* See if a character matches a character class, starting at the first colon
* of "[:class:]".
* If a valid character class is recognized, a pointer to the next character
* after the final closing bracket is stored into *end, otherwise a null
* pointer is stored into *end.
*/
static int
match_charclass(const char *p, wchar_t chr, const char **end)
{
char name[20];
char *nameend;
wctype_t cclass;
*end = NULL;
p++;
nameend = strstr(p, ":]");
if (nameend == NULL || (size_t)(nameend - p) >= sizeof(name) ||
nameend == p)
return 0;
memcpy(name, p, nameend - p);
name[nameend - p] = '\0';
*end = nameend + 2;
cclass = wctype(name);
/* An unknown class matches nothing but is valid nevertheless. */
if (cclass == 0)
return 0;
return iswctype(chr, cclass);
}
/*
* Returns true if the pattern matches the string.
*/
STATIC int
patmatch(const char *pattern, const char *string, int squoted)
{
const char *p, *q, *end;
const char *bt_p, *bt_q;
char c;
wchar_t wc, wc2;
p = pattern;
q = string;
bt_p = NULL;
bt_q = NULL;
for (;;) {
switch (c = *p++) {
case '\0':
if (*q != '\0')
goto backtrack;
return 1;
case CTLESC:
if (squoted && *q == CTLESC)
q++;
if (*q++ != *p++)
goto backtrack;
break;
case CTLQUOTEMARK:
continue;
case '?':
if (squoted && *q == CTLESC)
q++;
if (*q++ == '\0')
return 0;
break;
case '*':
c = *p;
while (c == CTLQUOTEMARK || c == '*')
c = *++p;
if (c != CTLESC && c != CTLQUOTEMARK &&
c != '?' && c != '*' && c != '[') {
while (*q != c) {
if (squoted && *q == CTLESC &&
q[1] == c)
break;
if (*q == '\0')
return 0;
if (squoted && *q == CTLESC)
q++;
q++;
}
}
/*
* First try the shortest match for the '*' that
* could work. We can forget any earlier '*' since
* there is no way having it match more characters
* can help us, given that we are already here.
*/
bt_p = p;
bt_q = q;
break;
case '[': {
const char *savep, *saveq, *endp;
int invert, found;
unsigned char chr;
endp = p;
if (*endp == '!')
endp++;
for (;;) {
while (*endp == CTLQUOTEMARK)
endp++;
if (*endp == '\0')
goto dft; /* no matching ] */
if (*endp == CTLESC)
endp++;
if (*++endp == ']')
break;
}
invert = 0;
savep = p, saveq = q;
invert = 0;
if (*p == '!' || *p == '^') {
invert++;
p++;
}
found = 0;
if (*q == '\0')
return 0;
chr = (unsigned char)*q++;
c = *p++;
do {
if (c == CTLQUOTEMARK)
continue;
if (c == '\0') {
p = savep, q = saveq;
c = '[';
goto dft;
}
if (c == '[' && *p == ':') {
found |= match_charclass(p, chr, &end);
if (end != NULL)
p = end;
}
if (c == CTLESC)
c = *p++;
wc = (unsigned char)c;
if (*p == '-' && p[1] != ']') {
p++;
if (*p == CTLESC)
p++;
wc2 = (unsigned char)*p++;
if ( collate_range_cmp(chr, wc) >= 0
&& collate_range_cmp(chr, wc2) <= 0
)
found = 1;
} else {
if (chr == wc)
found = 1;
}
} while ((c = *p++) != ']');
if (found == invert)
goto backtrack;
break;
}
dft: default:
if (squoted && *q == CTLESC)
q++;
if (*q++ == c)
break;
backtrack:
/*
* If we have a mismatch (other than hitting the end
* of the string), go back to the last '*' seen and
* have it match one additional character.
*/
if (bt_p == NULL)
return 0;
if (*bt_q == '\0')
return 0;
bt_q++;
p = bt_p;
q = bt_q;
break;
}
}
}
/*
* Remove any CTLESC characters from a string.
*/
void
rmescapes(char *str)
{
char *p, *q;
p = str;
while (*p != CTLESC && *p != CTLQUOTEMARK) {
if (*p++ == '\0')
return;
}
q = p;
while (*p) {
if (*p == CTLQUOTEMARK) {
p++;
continue;
}
if (*p == CTLESC)
p++;
*q++ = *p++;
}
*q = '\0';
}
/*
* See if a pattern matches in a case statement.
*/
int
casematch(union node *pattern, char *val)
{
struct stackmark smark;
int result;
char *p;
setstackmark(&smark);
argbackq = pattern->narg.backquote;
STARTSTACKSTR(expdest);
ifslastp = NULL;
argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
STPUTC('\0', expdest);
p = grabstackstr(expdest);
result = patmatch(p, val, 0);
popstackmark(&smark);
return result;
}
/*
* Our own itoa().
*/
STATIC char *
cvtnum(int num, char *buf)
{
char temp[32];
int neg = num < 0;
char *p = temp + 31;
temp[31] = '\0';
do {
*--p = num % 10 + '0';
} while ((num /= 10) != 0);
if (neg)
*--p = '-';
while (*p)
STPUTC(*p++, buf);
return buf;
}
/*
* Do most of the work for wordexp(3).
*/
int
wordexpcmd(int argc, char **argv)
{
size_t len;
int i;
out1fmt("%d", argc - 1);
out1c('\0');
for (i = 1, len = 0; i < argc; i++)
len += strlen(argv[i]);
out1fmt("%zu", len);
out1c('\0');
for (i = 1; i < argc; i++) {
out1str(argv[i]);
out1c('\0');
}
return (0);
}