mksh/syn.c

1219 lines
26 KiB
C

/* $OpenBSD: syn.c,v 1.30 2015/09/01 13:12:31 tedu Exp $ */
/*-
* Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009,
* 2011, 2012, 2013, 2014, 2015, 2016
* mirabilos <m@mirbsd.org>
*
* Provided that these terms and disclaimer and all copyright notices
* are retained or reproduced in an accompanying document, permission
* is granted to deal in this work without restriction, including un-
* limited rights to use, publicly perform, distribute, sell, modify,
* merge, give away, or sublicence.
*
* This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
* the utmost extent permitted by applicable law, neither express nor
* implied; without malicious intent or gross negligence. In no event
* may a licensor, author or contributor be held liable for indirect,
* direct, other damage, loss, or other issues arising in any way out
* of dealing in the work, even if advised of the possibility of such
* damage or existence of a defect, except proven that it results out
* of said person's immediate fault when using the work as intended.
*/
#include "sh.h"
__RCSID("$MirOS: src/bin/mksh/syn.c,v 1.111 2016/02/26 21:24:58 tg Exp $");
struct nesting_state {
int start_token; /* token than began nesting (eg, FOR) */
int start_line; /* line nesting began on */
};
struct yyrecursive_state {
struct ioword *old_heres[HERES];
struct yyrecursive_state *next;
struct ioword **old_herep;
int old_symbol;
int old_salias;
int old_nesting_type;
bool old_reject;
};
static void yyparse(void);
static struct op *pipeline(int);
static struct op *andor(void);
static struct op *c_list(bool);
static struct ioword *synio(int);
static struct op *nested(int, int, int);
static struct op *get_command(int);
static struct op *dogroup(void);
static struct op *thenpart(void);
static struct op *elsepart(void);
static struct op *caselist(void);
static struct op *casepart(int);
static struct op *function_body(char *, bool);
static char **wordlist(void);
static struct op *block(int, struct op *, struct op *);
static struct op *newtp(int);
static void syntaxerr(const char *) MKSH_A_NORETURN;
static void nesting_push(struct nesting_state *, int);
static void nesting_pop(struct nesting_state *);
static int inalias(struct source *) MKSH_A_PURE;
static Test_op dbtestp_isa(Test_env *, Test_meta);
static const char *dbtestp_getopnd(Test_env *, Test_op, bool);
static int dbtestp_eval(Test_env *, Test_op, const char *,
const char *, bool);
static void dbtestp_error(Test_env *, int, const char *) MKSH_A_NORETURN;
static struct op *outtree; /* yyparse output */
static struct nesting_state nesting; /* \n changed to ; */
static bool reject; /* token(cf) gets symbol again */
static int symbol; /* yylex value */
static int sALIAS = ALIAS; /* 0 in yyrecursive */
#define REJECT (reject = true)
#define ACCEPT (reject = false)
#define token(cf) ((reject) ? (ACCEPT, symbol) : (symbol = yylex(cf)))
#define tpeek(cf) ((reject) ? (symbol) : (REJECT, symbol = yylex(cf)))
#define musthave(c,cf) do { if (token(cf) != (c)) syntaxerr(NULL); } while (/* CONSTCOND */ 0)
static const char Tcbrace[] = "}";
static const char Tesac[] = "esac";
static void
yyparse(void)
{
int c;
ACCEPT;
outtree = c_list(source->type == SSTRING);
c = tpeek(0);
if (c == 0 && !outtree)
outtree = newtp(TEOF);
else if (c != '\n' && c != 0)
syntaxerr(NULL);
}
static struct op *
pipeline(int cf)
{
struct op *t, *p, *tl = NULL;
t = get_command(cf);
if (t != NULL) {
while (token(0) == '|') {
if ((p = get_command(CONTIN)) == NULL)
syntaxerr(NULL);
if (tl == NULL)
t = tl = block(TPIPE, t, p);
else
tl = tl->right = block(TPIPE, tl->right, p);
}
REJECT;
}
return (t);
}
static struct op *
andor(void)
{
struct op *t, *p;
int c;
t = pipeline(0);
if (t != NULL) {
while ((c = token(0)) == LOGAND || c == LOGOR) {
if ((p = pipeline(CONTIN)) == NULL)
syntaxerr(NULL);
t = block(c == LOGAND? TAND: TOR, t, p);
}
REJECT;
}
return (t);
}
static struct op *
c_list(bool multi)
{
struct op *t = NULL, *p, *tl = NULL;
int c;
bool have_sep;
while (/* CONSTCOND */ 1) {
p = andor();
/*
* Token has always been read/rejected at this point, so
* we don't worry about what flags to pass token()
*/
c = token(0);
have_sep = true;
if (c == '\n' && (multi || inalias(source))) {
if (!p)
/* ignore blank lines */
continue;
} else if (!p)
break;
else if (c == '&' || c == COPROC)
p = block(c == '&' ? TASYNC : TCOPROC, p, NULL);
else if (c != ';')
have_sep = false;
if (!t)
t = p;
else if (!tl)
t = tl = block(TLIST, t, p);
else
tl = tl->right = block(TLIST, tl->right, p);
if (!have_sep)
break;
}
REJECT;
return (t);
}
static const char IONDELIM_delim[] = { CHAR, '<', CHAR, '<', EOS };
static struct ioword *
synio(int cf)
{
struct ioword *iop;
static struct ioword *nextiop;
bool ishere;
if (nextiop != NULL) {
iop = nextiop;
nextiop = NULL;
return (iop);
}
if (tpeek(cf) != REDIR)
return (NULL);
ACCEPT;
iop = yylval.iop;
ishere = (iop->ioflag & IOTYPE) == IOHERE;
if (iop->ioflag & IOHERESTR) {
musthave(LWORD, 0);
} else if (ishere && tpeek(HEREDELIM) == '\n') {
ACCEPT;
yylval.cp = wdcopy(IONDELIM_delim, ATEMP);
iop->ioflag |= IOEVAL | IONDELIM;
} else
musthave(LWORD, ishere ? HEREDELIM : 0);
if (ishere) {
iop->delim = yylval.cp;
if (*ident != 0 && !(iop->ioflag & IOHERESTR)) {
/* unquoted */
iop->ioflag |= IOEVAL;
}
if (herep > &heres[HERES - 1])
yyerror("too many %ss\n", "<<");
*herep++ = iop;
} else
iop->ioname = yylval.cp;
if (iop->ioflag & IOBASH) {
char *cp;
nextiop = alloc(sizeof(*iop), ATEMP);
#ifdef MKSH_CONSERVATIVE_FDS
nextiop->ioname = cp = alloc(3, ATEMP);
#else
nextiop->ioname = cp = alloc(5, ATEMP);
if (iop->unit > 9) {
*cp++ = CHAR;
*cp++ = digits_lc[iop->unit / 10];
}
#endif
*cp++ = CHAR;
*cp++ = digits_lc[iop->unit % 10];
*cp = EOS;
iop->ioflag &= ~IOBASH;
nextiop->unit = 2;
nextiop->ioflag = IODUP;
nextiop->delim = NULL;
nextiop->heredoc = NULL;
}
return (iop);
}
static struct op *
nested(int type, int smark, int emark)
{
struct op *t;
struct nesting_state old_nesting;
nesting_push(&old_nesting, smark);
t = c_list(true);
musthave(emark, KEYWORD|sALIAS);
nesting_pop(&old_nesting);
return (block(type, t, NULL));
}
static const char let_cmd[] = {
QCHAR, 'l', CHAR, 'e', CHAR, 't', CHAR, ']', EOS
};
static const char setA_cmd0[] = {
QCHAR, 's', CHAR, 'e', CHAR, 't', EOS
};
static const char setA_cmd1[] = {
CHAR, '-', CHAR, 'A', EOS
};
static const char setA_cmd2[] = {
CHAR, '-', CHAR, '-', EOS
};
static struct op *
get_command(int cf)
{
struct op *t;
int c, iopn = 0, syniocf, lno;
struct ioword *iop, **iops;
XPtrV args, vars;
struct nesting_state old_nesting;
/* NUFILE is small enough to leave this addition unchecked */
iops = alloc2((NUFILE + 1), sizeof(struct ioword *), ATEMP);
XPinit(args, 16);
XPinit(vars, 16);
syniocf = KEYWORD|sALIAS;
switch (c = token(cf|KEYWORD|sALIAS|CMDASN)) {
default:
REJECT;
afree(iops, ATEMP);
XPfree(args);
XPfree(vars);
/* empty line */
return (NULL);
case LWORD:
case REDIR:
REJECT;
syniocf &= ~(KEYWORD|sALIAS);
t = newtp(TCOM);
t->lineno = source->line;
goto get_command_begin;
while (/* CONSTCOND */ 1) {
bool check_assign_cmd;
if (XPsize(args) == 0) {
get_command_begin:
check_assign_cmd = true;
cf = sALIAS | CMDASN;
} else if (t->u.evalflags)
cf = CMDWORD | CMDASN;
else
cf = CMDWORD;
switch (tpeek(cf)) {
case REDIR:
while ((iop = synio(cf)) != NULL) {
if (iopn >= NUFILE)
yyerror("too many %ss\n",
"redirection");
iops[iopn++] = iop;
}
break;
case LWORD:
ACCEPT;
/*
* the iopn == 0 and XPsize(vars) == 0 are
* dubious but AT&T ksh acts this way
*/
if (iopn == 0 && XPsize(vars) == 0 &&
check_assign_cmd) {
if (assign_command(ident, false))
t->u.evalflags = DOVACHECK;
else if (strcmp(ident, Tcommand) != 0)
check_assign_cmd = false;
}
if ((XPsize(args) == 0 || Flag(FKEYWORD)) &&
is_wdvarassign(yylval.cp))
XPput(vars, yylval.cp);
else
XPput(args, yylval.cp);
break;
case '(' /*)*/:
if (XPsize(args) == 0 && XPsize(vars) == 1 &&
is_wdvarassign(yylval.cp)) {
char *tcp;
/* wdarrassign: foo=(bar) */
ACCEPT;
/* manipulate the vars string */
tcp = XPptrv(vars)[(vars.len = 0)];
/* 'varname=' -> 'varname' */
tcp[wdscan(tcp, EOS) - tcp - 3] = EOS;
/* construct new args strings */
XPput(args, wdcopy(setA_cmd0, ATEMP));
XPput(args, wdcopy(setA_cmd1, ATEMP));
XPput(args, tcp);
XPput(args, wdcopy(setA_cmd2, ATEMP));
/* slurp in words till closing paren */
while (token(CONTIN) == LWORD)
XPput(args, yylval.cp);
if (symbol != /*(*/ ')')
syntaxerr(NULL);
} else {
/*
* Check for "> foo (echo hi)"
* which AT&T ksh allows (not
* POSIX, but not disallowed)
*/
afree(t, ATEMP);
if (XPsize(args) == 0 &&
XPsize(vars) == 0) {
ACCEPT;
goto Subshell;
}
/* must be a function */
if (iopn != 0 || XPsize(args) != 1 ||
XPsize(vars) != 0)
syntaxerr(NULL);
ACCEPT;
musthave(/*(*/')', 0);
t = function_body(XPptrv(args)[0], false);
}
goto Leave;
default:
goto Leave;
}
}
Leave:
break;
case '(': /*)*/ {
int subshell_nesting_type_saved;
Subshell:
subshell_nesting_type_saved = subshell_nesting_type;
subshell_nesting_type = ')';
t = nested(TPAREN, '(', ')');
subshell_nesting_type = subshell_nesting_type_saved;
break;
}
case '{': /*}*/
t = nested(TBRACE, '{', '}');
break;
case MDPAREN:
/* leave KEYWORD in syniocf (allow if (( 1 )) then ...) */
lno = source->line;
ACCEPT;
switch (token(LETEXPR)) {
case LWORD:
break;
case '(': /*)*/
c = '(';
goto Subshell;
default:
syntaxerr(NULL);
}
t = newtp(TCOM);
t->lineno = lno;
XPput(args, wdcopy(let_cmd, ATEMP));
XPput(args, yylval.cp);
break;
case DBRACKET: /* [[ .. ]] */
/* leave KEYWORD in syniocf (allow if [[ -n 1 ]] then ...) */
t = newtp(TDBRACKET);
ACCEPT;
{
Test_env te;
te.flags = TEF_DBRACKET;
te.pos.av = &args;
te.isa = dbtestp_isa;
te.getopnd = dbtestp_getopnd;
te.eval = dbtestp_eval;
te.error = dbtestp_error;
test_parse(&te);
}
break;
case FOR:
case SELECT:
t = newtp((c == FOR) ? TFOR : TSELECT);
musthave(LWORD, CMDASN);
if (!is_wdvarname(yylval.cp, true))
yyerror("%s: bad identifier\n",
c == FOR ? "for" : Tselect);
strdupx(t->str, ident, ATEMP);
nesting_push(&old_nesting, c);
t->vars = wordlist();
t->left = dogroup();
nesting_pop(&old_nesting);
break;
case WHILE:
case UNTIL:
nesting_push(&old_nesting, c);
t = newtp((c == WHILE) ? TWHILE : TUNTIL);
t->left = c_list(true);
t->right = dogroup();
nesting_pop(&old_nesting);
break;
case CASE:
t = newtp(TCASE);
musthave(LWORD, 0);
t->str = yylval.cp;
nesting_push(&old_nesting, c);
t->left = caselist();
nesting_pop(&old_nesting);
break;
case IF:
nesting_push(&old_nesting, c);
t = newtp(TIF);
t->left = c_list(true);
t->right = thenpart();
musthave(FI, KEYWORD|sALIAS);
nesting_pop(&old_nesting);
break;
case BANG:
syniocf &= ~(KEYWORD|sALIAS);
t = pipeline(0);
if (t == NULL)
syntaxerr(NULL);
t = block(TBANG, NULL, t);
break;
case TIME:
syniocf &= ~(KEYWORD|sALIAS);
t = pipeline(0);
if (t && t->type == TCOM) {
t->str = alloc(2, ATEMP);
/* TF_* flags */
t->str[0] = '\0';
t->str[1] = '\0';
}
t = block(TTIME, t, NULL);
break;
case FUNCTION:
musthave(LWORD, 0);
t = function_body(yylval.cp, true);
break;
}
while ((iop = synio(syniocf)) != NULL) {
if (iopn >= NUFILE)
yyerror("too many %ss\n", "redirection");
iops[iopn++] = iop;
}
if (iopn == 0) {
afree(iops, ATEMP);
t->ioact = NULL;
} else {
iops[iopn++] = NULL;
iops = aresize2(iops, iopn, sizeof(struct ioword *), ATEMP);
t->ioact = iops;
}
if (t->type == TCOM || t->type == TDBRACKET) {
XPput(args, NULL);
t->args = (const char **)XPclose(args);
XPput(vars, NULL);
t->vars = (char **)XPclose(vars);
} else {
XPfree(args);
XPfree(vars);
}
if (c == MDPAREN) {
t = block(TBRACE, t, NULL);
t->ioact = t->left->ioact;
t->left->ioact = NULL;
}
return (t);
}
static struct op *
dogroup(void)
{
int c;
struct op *list;
c = token(CONTIN|KEYWORD|sALIAS);
/*
* A {...} can be used instead of do...done for for/select loops
* but not for while/until loops - we don't need to check if it
* is a while loop because it would have been parsed as part of
* the conditional command list...
*/
if (c == DO)
c = DONE;
else if (c == '{')
c = '}';
else
syntaxerr(NULL);
list = c_list(true);
musthave(c, KEYWORD|sALIAS);
return (list);
}
static struct op *
thenpart(void)
{
struct op *t;
musthave(THEN, KEYWORD|sALIAS);
t = newtp(0);
t->left = c_list(true);
if (t->left == NULL)
syntaxerr(NULL);
t->right = elsepart();
return (t);
}
static struct op *
elsepart(void)
{
struct op *t;
switch (token(KEYWORD|sALIAS|CMDASN)) {
case ELSE:
if ((t = c_list(true)) == NULL)
syntaxerr(NULL);
return (t);
case ELIF:
t = newtp(TELIF);
t->left = c_list(true);
t->right = thenpart();
return (t);
default:
REJECT;
}
return (NULL);
}
static struct op *
caselist(void)
{
struct op *t, *tl;
int c;
c = token(CONTIN|KEYWORD|sALIAS);
/* A {...} can be used instead of in...esac for case statements */
if (c == IN)
c = ESAC;
else if (c == '{')
c = '}';
else
syntaxerr(NULL);
t = tl = NULL;
/* no ALIAS here */
while ((tpeek(CONTIN|KEYWORD|ESACONLY)) != c) {
struct op *tc = casepart(c);
if (tl == NULL)
t = tl = tc, tl->right = NULL;
else
tl->right = tc, tl = tc;
}
musthave(c, KEYWORD|sALIAS);
return (t);
}
static struct op *
casepart(int endtok)
{
struct op *t;
XPtrV ptns;
XPinit(ptns, 16);
t = newtp(TPAT);
/* no ALIAS here */
if (token(CONTIN | KEYWORD) != '(')
REJECT;
do {
switch (token(0)) {
case LWORD:
break;
case '}':
case ESAC:
if (symbol != endtok) {
strdupx(yylval.cp,
symbol == '}' ? Tcbrace : Tesac, ATEMP);
break;
}
/* FALLTHROUGH */
default:
syntaxerr(NULL);
}
XPput(ptns, yylval.cp);
} while (token(0) == '|');
REJECT;
XPput(ptns, NULL);
t->vars = (char **)XPclose(ptns);
musthave(')', 0);
t->left = c_list(true);
/* initialise to default for ;; or omitted */
t->u.charflag = ';';
/* SUSv4 requires the ;; except in the last casepart */
if ((tpeek(CONTIN|KEYWORD|sALIAS)) != endtok)
switch (symbol) {
default:
syntaxerr(NULL);
case BRKEV:
t->u.charflag = '|';
if (0)
/* FALLTHROUGH */
case BRKFT:
t->u.charflag = '&';
/* FALLTHROUGH */
case BREAK:
/* initialised above, but we need to eat the token */
ACCEPT;
}
return (t);
}
static struct op *
function_body(char *name,
/* function foo { ... } vs foo() { .. } */
bool ksh_func)
{
char *sname, *p;
struct op *t;
sname = wdstrip(name, 0);
/*-
* Check for valid characters in name. POSIX and AT&T ksh93 say
* only allow [a-zA-Z_0-9] but this allows more as old pdkshs
* have allowed more; the following were never allowed:
* NUL TAB NL SP " $ & ' ( ) ; < = > \ ` |
* C_QUOTE covers all but adds # * ? [ ]
*/
for (p = sname; *p; p++)
if (ctype(*p, C_QUOTE))
yyerror("%s: invalid function name\n", sname);
/*
* Note that POSIX allows only compound statements after foo(),
* sh and AT&T ksh allow any command, go with the later since it
* shouldn't break anything. However, for function foo, AT&T ksh
* only accepts an open-brace.
*/
if (ksh_func) {
if (tpeek(CONTIN|KEYWORD|sALIAS) == '(' /*)*/) {
/* function foo () { //}*/
ACCEPT;
musthave(')', 0);
/* degrade to POSIX function */
ksh_func = false;
}
musthave('{' /*}*/, CONTIN|KEYWORD|sALIAS);
REJECT;
}
t = newtp(TFUNCT);
t->str = sname;
t->u.ksh_func = tobool(ksh_func);
t->lineno = source->line;
if ((t->left = get_command(CONTIN)) == NULL) {
char *tv;
/*
* Probably something like foo() followed by EOF or ';'.
* This is accepted by sh and ksh88.
* To make "typeset -f foo" work reliably (so its output can
* be used as input), we pretend there is a colon here.
*/
t->left = newtp(TCOM);
/* (2 * sizeof(char *)) is small enough */
t->left->args = alloc(2 * sizeof(char *), ATEMP);
t->left->args[0] = tv = alloc(3, ATEMP);
tv[0] = QCHAR;
tv[1] = ':';
tv[2] = EOS;
t->left->args[1] = NULL;
t->left->vars = alloc(sizeof(char *), ATEMP);
t->left->vars[0] = NULL;
t->left->lineno = 1;
}
return (t);
}
static char **
wordlist(void)
{
int c;
XPtrV args;
XPinit(args, 16);
/* POSIX does not do alias expansion here... */
if ((c = token(CONTIN|KEYWORD|sALIAS)) != IN) {
if (c != ';')
/* non-POSIX, but AT&T ksh accepts a ; here */
REJECT;
return (NULL);
}
while ((c = token(0)) == LWORD)
XPput(args, yylval.cp);
if (c != '\n' && c != ';')
syntaxerr(NULL);
XPput(args, NULL);
return ((char **)XPclose(args));
}
/*
* supporting functions
*/
static struct op *
block(int type, struct op *t1, struct op *t2)
{
struct op *t;
t = newtp(type);
t->left = t1;
t->right = t2;
return (t);
}
static const struct tokeninfo {
const char *name;
short val;
short reserved;
} tokentab[] = {
/* Reserved words */
{ "if", IF, true },
{ "then", THEN, true },
{ "else", ELSE, true },
{ "elif", ELIF, true },
{ "fi", FI, true },
{ "case", CASE, true },
{ Tesac, ESAC, true },
{ "for", FOR, true },
{ Tselect, SELECT, true },
{ "while", WHILE, true },
{ "until", UNTIL, true },
{ "do", DO, true },
{ "done", DONE, true },
{ "in", IN, true },
{ Tfunction, FUNCTION, true },
{ "time", TIME, true },
{ "{", '{', true },
{ Tcbrace, '}', true },
{ "!", BANG, true },
{ "[[", DBRACKET, true },
/* Lexical tokens (0[EOF], LWORD and REDIR handled specially) */
{ "&&", LOGAND, false },
{ "||", LOGOR, false },
{ ";;", BREAK, false },
{ ";|", BRKEV, false },
{ ";&", BRKFT, false },
{ "((", MDPAREN, false },
{ "|&", COPROC, false },
/* and some special cases... */
{ "newline", '\n', false },
{ NULL, 0, false }
};
void
initkeywords(void)
{
struct tokeninfo const *tt;
struct tbl *p;
ktinit(APERM, &keywords,
/* currently 28 keywords: 75% of 64 = 2^6 */
6);
for (tt = tokentab; tt->name; tt++) {
if (tt->reserved) {
p = ktenter(&keywords, tt->name, hash(tt->name));
p->flag |= DEFINED|ISSET;
p->type = CKEYWD;
p->val.i = tt->val;
}
}
}
static void
syntaxerr(const char *what)
{
/* 23<<- is the longest redirection, I think */
char redir[8];
const char *s;
struct tokeninfo const *tt;
int c;
if (!what)
what = "unexpected";
REJECT;
c = token(0);
Again:
switch (c) {
case 0:
if (nesting.start_token) {
c = nesting.start_token;
source->errline = nesting.start_line;
what = "unmatched";
goto Again;
}
/* don't quote the EOF */
yyerror("%s: unexpected EOF\n", Tsynerr);
/* NOTREACHED */
case LWORD:
s = snptreef(NULL, 32, "%S", yylval.cp);
break;
case REDIR:
s = snptreef(redir, sizeof(redir), "%R", yylval.iop);
break;
default:
for (tt = tokentab; tt->name; tt++)
if (tt->val == c)
break;
if (tt->name)
s = tt->name;
else {
if (c > 0 && c < 256) {
redir[0] = c;
redir[1] = '\0';
} else
shf_snprintf(redir, sizeof(redir),
"?%d", c);
s = redir;
}
}
yyerror("%s: '%s' %s\n", Tsynerr, s, what);
}
static void
nesting_push(struct nesting_state *save, int tok)
{
*save = nesting;
nesting.start_token = tok;
nesting.start_line = source->line;
}
static void
nesting_pop(struct nesting_state *saved)
{
nesting = *saved;
}
static struct op *
newtp(int type)
{
struct op *t;
t = alloc(sizeof(struct op), ATEMP);
t->type = type;
t->u.evalflags = 0;
t->args = NULL;
t->vars = NULL;
t->ioact = NULL;
t->left = t->right = NULL;
t->str = NULL;
return (t);
}
struct op *
compile(Source *s, bool skiputf8bom)
{
nesting.start_token = 0;
nesting.start_line = 0;
herep = heres;
source = s;
if (skiputf8bom)
yyskiputf8bom();
yyparse();
return (outtree);
}
/*-
* This kludge exists to take care of sh/AT&T ksh oddity in which
* the arguments of alias/export/readonly/typeset have no field
* splitting, file globbing, or (normal) tilde expansion done.
* AT&T ksh seems to do something similar to this since
* $ touch a=a; typeset a=[ab]; echo "$a"
* a=[ab]
* $ x=typeset; $x a=[ab]; echo "$a"
* a=a
* $
*/
int
assign_command(const char *s, bool docommand)
{
if (!*s)
return (0);
return ((strcmp(s, Talias) == 0) ||
(strcmp(s, Texport) == 0) ||
(strcmp(s, Treadonly) == 0) ||
(docommand && (strcmp(s, Tcommand) == 0)) ||
(strcmp(s, Ttypeset) == 0));
}
/* Check if we are in the middle of reading an alias */
static int
inalias(struct source *s)
{
for (; s && s->type == SALIAS; s = s->next)
if (!(s->flags & SF_ALIASEND))
return (1);
return (0);
}
/*
* Order important - indexed by Test_meta values
* Note that ||, &&, ( and ) can't appear in as unquoted strings
* in normal shell input, so these can be interpreted unambiguously
* in the evaluation pass.
*/
static const char dbtest_or[] = { CHAR, '|', CHAR, '|', EOS };
static const char dbtest_and[] = { CHAR, '&', CHAR, '&', EOS };
static const char dbtest_not[] = { CHAR, '!', EOS };
static const char dbtest_oparen[] = { CHAR, '(', EOS };
static const char dbtest_cparen[] = { CHAR, ')', EOS };
const char * const dbtest_tokens[] = {
dbtest_or, dbtest_and, dbtest_not,
dbtest_oparen, dbtest_cparen
};
static const char db_close[] = { CHAR, ']', CHAR, ']', EOS };
static const char db_lthan[] = { CHAR, '<', EOS };
static const char db_gthan[] = { CHAR, '>', EOS };
/*
* Test if the current token is a whatever. Accepts the current token if
* it is. Returns 0 if it is not, non-zero if it is (in the case of
* TM_UNOP and TM_BINOP, the returned value is a Test_op).
*/
static Test_op
dbtestp_isa(Test_env *te, Test_meta meta)
{
int c = tpeek(CMDASN | (meta == TM_BINOP ? 0 : CONTIN));
bool uqword;
char *save = NULL;
Test_op ret = TO_NONOP;
/* unquoted word? */
uqword = c == LWORD && *ident;
if (meta == TM_OR)
ret = c == LOGOR ? TO_NONNULL : TO_NONOP;
else if (meta == TM_AND)
ret = c == LOGAND ? TO_NONNULL : TO_NONOP;
else if (meta == TM_NOT)
ret = (uqword && !strcmp(yylval.cp,
dbtest_tokens[(int)TM_NOT])) ? TO_NONNULL : TO_NONOP;
else if (meta == TM_OPAREN)
ret = c == '(' /*)*/ ? TO_NONNULL : TO_NONOP;
else if (meta == TM_CPAREN)
ret = c == /*(*/ ')' ? TO_NONNULL : TO_NONOP;
else if (meta == TM_UNOP || meta == TM_BINOP) {
if (meta == TM_BINOP && c == REDIR &&
(yylval.iop->ioflag == IOREAD ||
yylval.iop->ioflag == IOWRITE)) {
ret = TO_NONNULL;
save = wdcopy(yylval.iop->ioflag == IOREAD ?
db_lthan : db_gthan, ATEMP);
} else if (uqword && (ret = test_isop(meta, ident)))
save = yylval.cp;
} else
/* meta == TM_END */
ret = (uqword && !strcmp(yylval.cp,
db_close)) ? TO_NONNULL : TO_NONOP;
if (ret != TO_NONOP) {
ACCEPT;
if ((unsigned int)meta < NELEM(dbtest_tokens))
save = wdcopy(dbtest_tokens[(int)meta], ATEMP);
if (save)
XPput(*te->pos.av, save);
}
return (ret);
}
static const char *
dbtestp_getopnd(Test_env *te, Test_op op MKSH_A_UNUSED,
bool do_eval MKSH_A_UNUSED)
{
int c = tpeek(CMDASN);
if (c != LWORD)
return (NULL);
ACCEPT;
XPput(*te->pos.av, yylval.cp);
return (null);
}
static int
dbtestp_eval(Test_env *te MKSH_A_UNUSED, Test_op op MKSH_A_UNUSED,
const char *opnd1 MKSH_A_UNUSED, const char *opnd2 MKSH_A_UNUSED,
bool do_eval MKSH_A_UNUSED)
{
return (1);
}
static void
dbtestp_error(Test_env *te, int offset, const char *msg)
{
te->flags |= TEF_ERROR;
if (offset < 0) {
REJECT;
/* Kludgy to say the least... */
symbol = LWORD;
yylval.cp = *(XPptrv(*te->pos.av) + XPsize(*te->pos.av) +
offset);
}
syntaxerr(msg);
}
#if HAVE_SELECT
#ifndef EOVERFLOW
#ifdef ERANGE
#define EOVERFLOW ERANGE
#else
#define EOVERFLOW EINVAL
#endif
#endif
bool
parse_usec(const char *s, struct timeval *tv)
{
struct timeval tt;
int i;
tv->tv_sec = 0;
/* parse integral part */
while (ksh_isdigit(*s)) {
tt.tv_sec = tv->tv_sec * 10 + ksh_numdig(*s++);
/*XXX this overflow check maybe UB */
if (tt.tv_sec / 10 != tv->tv_sec) {
errno = EOVERFLOW;
return (true);
}
tv->tv_sec = tt.tv_sec;
}
tv->tv_usec = 0;
if (!*s)
/* no decimal fraction */
return (false);
else if (*s++ != '.') {
/* junk after integral part */
errno = EINVAL;
return (true);
}
/* parse decimal fraction */
i = 100000;
while (ksh_isdigit(*s)) {
tv->tv_usec += i * ksh_numdig(*s++);
if (i == 1)
break;
i /= 10;
}
/* check for junk after fractional part */
while (ksh_isdigit(*s))
++s;
if (*s) {
errno = EINVAL;
return (true);
}
/* end of input string reached, no errors */
return (false);
}
#endif
/*
* Helper function called from within lex.c:yylex() to parse
* a COMSUB recursively using the main shell parser and lexer
*/
char *
yyrecursive(int subtype MKSH_A_UNUSED)
{
struct op *t;
char *cp;
struct yyrecursive_state *ys;
int stok, etok;
if (subtype != COMSUB) {
stok = '{';
etok = '}';
} else {
stok = '(';
etok = ')';
}
ys = alloc(sizeof(struct yyrecursive_state), ATEMP);
/* tell the lexer to accept a closing parenthesis as EOD */
ys->old_nesting_type = subshell_nesting_type;
subshell_nesting_type = etok;
/* push reject state, parse recursively, pop reject state */
ys->old_reject = reject;
ys->old_symbol = symbol;
ACCEPT;
memcpy(ys->old_heres, heres, sizeof(heres));
ys->old_herep = herep;
herep = heres;
ys->old_salias = sALIAS;
sALIAS = 0;
ys->next = e->yyrecursive_statep;
e->yyrecursive_statep = ys;
/* we use TPAREN as a helper container here */
t = nested(TPAREN, stok, etok);
yyrecursive_pop(false);
/* t->left because nested(TPAREN, ...) hides our goodies there */
cp = snptreef(NULL, 0, "%T", t->left);
tfree(t, ATEMP);
return (cp);
}
void
yyrecursive_pop(bool popall)
{
struct yyrecursive_state *ys;
popnext:
if (!(ys = e->yyrecursive_statep))
return;
e->yyrecursive_statep = ys->next;
sALIAS = ys->old_salias;
memcpy(heres, ys->old_heres, sizeof(heres));
herep = ys->old_herep;
reject = ys->old_reject;
symbol = ys->old_symbol;
subshell_nesting_type = ys->old_nesting_type;
afree(ys, ATEMP);
if (popall)
goto popnext;
}