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/* $OpenBSD: lex.c,v 1.48 2013/11/12 04:36:02 deraadt Exp $ */
/*-
* Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
* 2011, 2012, 2013
* Thorsten Glaser <tg@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/lex.c,v 1.190 2013/11/17 22:19:42 tg Exp $");
/*
* states while lexing word
*/
#define SBASE 0 /* outside any lexical constructs */
#define SWORD 1 /* implicit quoting for substitute() */
#define SLETPAREN 2 /* inside (( )), implicit quoting */
#define SSQUOTE 3 /* inside '' */
#define SDQUOTE 4 /* inside "" */
#define SEQUOTE 5 /* inside $'' */
#define SBRACE 6 /* inside ${} */
#define SQBRACE 7 /* inside "${}" */
#define SBQUOTE 8 /* inside `` */
#define SASPAREN 9 /* inside $(( )) */
#define SHEREDELIM 10 /* parsing <<,<<-,<<< delimiter */
#define SHEREDQUOTE 11 /* parsing " in <<,<<-,<<< delimiter */
#define SPATTERN 12 /* parsing *(...|...) pattern (*+?@!) */
#define SADELIM 13 /* like SBASE, looking for delimiter */
#define STBRACEKORN 14 /* parsing ${...[#%]...} !FSH */
#define STBRACEBOURNE 15 /* parsing ${...[#%]...} FSH */
#define SINVALID 255 /* invalid state */
struct sretrace_info {
struct sretrace_info *next;
XString xs;
char *xp;
};
/*
* Structure to keep track of the lexing state and the various pieces of info
* needed for each particular state.
*/
typedef struct lex_state {
union {
/* point to the next state block */
struct lex_state *base;
/* marks start of state output in output string */
int start;
/* SBQUOTE: true if in double quotes: "`...`" */
/* SEQUOTE: got NUL, ignore rest of string */
bool abool;
/* SADELIM information */
struct {
/* character to search for */
unsigned char delimiter;
/* max. number of delimiters */
unsigned char num;
} adelim;
} u;
/* count open parentheses */
short nparen;
/* type of this state */
uint8_t type;
} Lex_state;
#define ls_base u.base
#define ls_start u.start
#define ls_bool u.abool
#define ls_adelim u.adelim
typedef struct {
Lex_state *base;
Lex_state *end;
} State_info;
static void readhere(struct ioword *);
static void ungetsc(int);
static void ungetsc_i(int);
static int getsc_uu(void);
static void getsc_line(Source *);
static int getsc_bn(void);
static int s_get(void);
static void s_put(int);
static char *get_brace_var(XString *, char *);
static bool arraysub(char **);
static void gethere(bool);
static Lex_state *push_state_i(State_info *, Lex_state *);
static Lex_state *pop_state_i(State_info *, Lex_state *);
static int backslash_skip;
static int ignore_backslash_newline;
/* optimised getsc_bn() */
#define o_getsc() (*source->str != '\0' && *source->str != '\\' && \
!backslash_skip ? *source->str++ : getsc_bn())
/* optimised getsc_uu() */
#define o_getsc_u() ((*source->str != '\0') ? *source->str++ : getsc_uu())
/* retrace helper */
#define o_getsc_r(carg) { \
int cev = (carg); \
struct sretrace_info *rp = retrace_info; \
\
while (rp) { \
Xcheck(rp->xs, rp->xp); \
*rp->xp++ = cev; \
rp = rp->next; \
} \
\
return (cev); \
}
#if defined(MKSH_SMALL) && !defined(MKSH_SMALL_BUT_FAST)
static int getsc(void);
static int
getsc(void)
{
o_getsc_r(o_getsc());
}
#else
static int getsc_r(int);
static int
getsc_r(int c)
{
o_getsc_r(c);
}
#define getsc() getsc_r(o_getsc())
#endif
#define STATE_BSIZE 8
#define PUSH_STATE(s) do { \
if (++statep == state_info.end) \
statep = push_state_i(&state_info, statep); \
state = statep->type = (s); \
} while (/* CONSTCOND */ 0)
#define POP_STATE() do { \
if (--statep == state_info.base) \
statep = pop_state_i(&state_info, statep); \
state = statep->type; \
} while (/* CONSTCOND */ 0)
#define PUSH_SRETRACE() do { \
struct sretrace_info *ri; \
\
statep->ls_start = Xsavepos(ws, wp); \
ri = alloc(sizeof(struct sretrace_info), ATEMP); \
Xinit(ri->xs, ri->xp, 64, ATEMP); \
ri->next = retrace_info; \
retrace_info = ri; \
} while (/* CONSTCOND */ 0)
#define POP_SRETRACE() do { \
wp = Xrestpos(ws, wp, statep->ls_start); \
*retrace_info->xp = '\0'; \
sp = Xstring(retrace_info->xs, retrace_info->xp); \
dp = (void *)retrace_info; \
retrace_info = retrace_info->next; \
afree(dp, ATEMP); \
} while (/* CONSTCOND */ 0)
/**
* Lexical analyser
*
* tokens are not regular expressions, they are LL(1).
* for example, "${var:-${PWD}}", and "$(size $(whence ksh))".
* hence the state stack. Note "$(...)" are now parsed recursively.
*/
int
yylex(int cf)
{
Lex_state states[STATE_BSIZE], *statep, *s2, *base;
State_info state_info;
int c, c2, state;
size_t cz;
XString ws; /* expandable output word */
char *wp; /* output word pointer */
char *sp, *dp;
Again:
states[0].type = SINVALID;
states[0].ls_base = NULL;
statep = &states[1];
state_info.base = states;
state_info.end = &state_info.base[STATE_BSIZE];
Xinit(ws, wp, 64, ATEMP);
backslash_skip = 0;
ignore_backslash_newline = 0;
if (cf & ONEWORD)
state = SWORD;
else if (cf & LETEXPR) {
/* enclose arguments in (double) quotes */
*wp++ = OQUOTE;
state = SLETPAREN;
statep->nparen = 0;
} else {
/* normal lexing */
state = (cf & HEREDELIM) ? SHEREDELIM : SBASE;
while ((c = getsc()) == ' ' || c == '\t')
;
if (c == '#') {
ignore_backslash_newline++;
while ((c = getsc()) != '\0' && c != '\n')
;
ignore_backslash_newline--;
}
ungetsc(c);
}
if (source->flags & SF_ALIAS) {
/* trailing ' ' in alias definition */
source->flags &= ~SF_ALIAS;
cf |= ALIAS;
}
/* Initial state: one of SWORD SLETPAREN SHEREDELIM SBASE */
statep->type = state;
/* check for here string */
if (state == SHEREDELIM) {
c = getsc();
if (c == '<') {
state = SHEREDELIM;
while ((c = getsc()) == ' ' || c == '\t')
;
ungetsc(c);
c = '<';
goto accept_nonword;
}
ungetsc(c);
}
/* collect non-special or quoted characters to form word */
while (!((c = getsc()) == 0 ||
((state == SBASE || state == SHEREDELIM) && ctype(c, C_LEX1)))) {
if (state == SBASE &&
subshell_nesting_type == /*{*/ '}' &&
c == /*{*/ '}')
/* possibly end ${ :;} */
break;
accept_nonword:
Xcheck(ws, wp);
switch (state) {
case SADELIM:
if (c == '(')
statep->nparen++;
else if (c == ')')
statep->nparen--;
else if (statep->nparen == 0 && (c == /*{*/ '}' ||
c == (int)statep->ls_adelim.delimiter)) {
*wp++ = ADELIM;
*wp++ = c;
if (c == /*{*/ '}' || --statep->ls_adelim.num == 0)
POP_STATE();
if (c == /*{*/ '}')
POP_STATE();
break;
}
/* FALLTHROUGH */
case SBASE:
if (c == '[' && (cf & (VARASN|ARRAYVAR))) {
/* temporary */
*wp = EOS;
if (is_wdvarname(Xstring(ws, wp), false)) {
char *p, *tmp;
if (arraysub(&tmp)) {
*wp++ = CHAR;
*wp++ = c;
for (p = tmp; *p; ) {
Xcheck(ws, wp);
*wp++ = CHAR;
*wp++ = *p++;
}
afree(tmp, ATEMP);
break;
} else {
Source *s;
s = pushs(SREREAD,
source->areap);
s->start = s->str =
s->u.freeme = tmp;
s->next = source;
source = s;
}
}
*wp++ = CHAR;
*wp++ = c;
break;
}
/* FALLTHROUGH */
Sbase1: /* includes *(...|...) pattern (*+?@!) */
if (c == '*' || c == '@' || c == '+' || c == '?' ||
c == '!') {
c2 = getsc();
if (c2 == '(' /*)*/ ) {
*wp++ = OPAT;
*wp++ = c;
PUSH_STATE(SPATTERN);
break;
}
ungetsc(c2);
}
/* FALLTHROUGH */
Sbase2: /* doesn't include *(...|...) pattern (*+?@!) */
switch (c) {
case '\\':
getsc_qchar:
if ((c = getsc())) {
/* trailing \ is lost */
*wp++ = QCHAR;
*wp++ = c;
}
break;
case '\'':
open_ssquote_unless_heredoc:
if ((cf & HEREDOC))
goto store_char;
*wp++ = OQUOTE;
ignore_backslash_newline++;
PUSH_STATE(SSQUOTE);
break;
case '"':
open_sdquote:
*wp++ = OQUOTE;
PUSH_STATE(SDQUOTE);
break;
case '$':
/*
* processing of dollar sign belongs into
* Subst, except for those which can open
* a string: $'…' and $"…"
*/
subst_dollar_ex:
c = getsc();
switch (c) {
case '"':
goto open_sdquote;
case '\'':
goto open_sequote;
default:
goto SubstS;
}
default:
goto Subst;
}
break;
Subst:
switch (c) {
case '\\':
c = getsc();
switch (c) {
case '"':
if ((cf & HEREDOC))
goto heredocquote;
/* FALLTHROUGH */
case '\\':
case '$': case '`':
store_qchar:
*wp++ = QCHAR;
*wp++ = c;
break;
default:
heredocquote:
Xcheck(ws, wp);
if (c) {
/* trailing \ is lost */
*wp++ = CHAR;
*wp++ = '\\';
*wp++ = CHAR;
*wp++ = c;
}
break;
}
break;
case '$':
c = getsc();
SubstS:
if (c == '(') /*)*/ {
c = getsc();
if (c == '(') /*)*/ {
*wp++ = EXPRSUB;
PUSH_STATE(SASPAREN);
statep->nparen = 2;
PUSH_SRETRACE();
*retrace_info->xp++ = '(';
} else {
ungetsc(c);
subst_command:
c = COMSUB;
subst_command2:
sp = yyrecursive(c);
cz = strlen(sp) + 1;
XcheckN(ws, wp, cz);
*wp++ = c;
memcpy(wp, sp, cz);
wp += cz;
}
} else if (c == '{') /*}*/ {
if ((c = getsc()) == '|') {
/*
* non-subenvironment
* value substitution
*/
c = VALSUB;
goto subst_command2;
} else if (ctype(c, C_IFSWS)) {
/*
* non-subenvironment
* "command" substitution
*/
c = FUNSUB;
goto subst_command2;
}
ungetsc(c);
*wp++ = OSUBST;
*wp++ = '{'; /*}*/
wp = get_brace_var(&ws, wp);
c = getsc();
/* allow :# and :% (ksh88 compat) */
if (c == ':') {
*wp++ = CHAR;
*wp++ = c;
c = getsc();
if (c == ':') {
*wp++ = CHAR;
*wp++ = '0';
*wp++ = ADELIM;
*wp++ = ':';
PUSH_STATE(SBRACE);
PUSH_STATE(SADELIM);
statep->ls_adelim.delimiter = ':';
statep->ls_adelim.num = 1;
statep->nparen = 0;
break;
} else if (ksh_isdigit(c) ||
c == '('/*)*/ || c == ' ' ||
/*XXX what else? */
c == '$') {
/* substring subst. */
if (c != ' ') {
*wp++ = CHAR;
*wp++ = ' ';
}
ungetsc(c);
PUSH_STATE(SBRACE);
PUSH_STATE(SADELIM);
statep->ls_adelim.delimiter = ':';
statep->ls_adelim.num = 2;
statep->nparen = 0;
break;
}
} else if (c == '/') {
*wp++ = CHAR;
*wp++ = c;
if ((c = getsc()) == '/') {
*wp++ = ADELIM;
*wp++ = c;
} else
ungetsc(c);
PUSH_STATE(SBRACE);
PUSH_STATE(SADELIM);
statep->ls_adelim.delimiter = '/';
statep->ls_adelim.num = 1;
statep->nparen = 0;
break;
}
/*
* If this is a trim operation,
* treat (,|,) specially in STBRACE.
*/
if (ctype(c, C_SUBOP2)) {
ungetsc(c);
if (Flag(FSH))
PUSH_STATE(STBRACEBOURNE);
else
PUSH_STATE(STBRACEKORN);
} else {
ungetsc(c);
if (state == SDQUOTE ||
state == SQBRACE)
PUSH_STATE(SQBRACE);
else
PUSH_STATE(SBRACE);
}
} else if (ksh_isalphx(c)) {
*wp++ = OSUBST;
*wp++ = 'X';
do {
Xcheck(ws, wp);
*wp++ = c;
c = getsc();
} while (ksh_isalnux(c));
*wp++ = '\0';
*wp++ = CSUBST;
*wp++ = 'X';
ungetsc(c);
} else if (ctype(c, C_VAR1 | C_DIGIT)) {
Xcheck(ws, wp);
*wp++ = OSUBST;
*wp++ = 'X';
*wp++ = c;
*wp++ = '\0';
*wp++ = CSUBST;
*wp++ = 'X';
} else {
*wp++ = CHAR;
*wp++ = '$';
ungetsc(c);
}
break;
case '`':
subst_gravis:
PUSH_STATE(SBQUOTE);
*wp++ = COMSUB;
/*
* Need to know if we are inside double quotes
* since sh/AT&T-ksh translate the \" to " in
* "`...\"...`".
* This is not done in POSIX mode (section
* 3.2.3, Double Quotes: "The backquote shall
* retain its special meaning introducing the
* other form of command substitution (see
* 3.6.3). The portion of the quoted string
* from the initial backquote and the
* characters up to the next backquote that
* is not preceded by a backslash (having
* escape characters removed) defines that
* command whose output replaces `...` when
* the word is expanded."
* Section 3.6.3, Command Substitution:
* "Within the backquoted style of command
* substitution, backslash shall retain its
* literal meaning, except when followed by
* $ ` \.").
*/
statep->ls_bool = false;
s2 = statep;
base = state_info.base;
while (/* CONSTCOND */ 1) {
for (; s2 != base; s2--) {
if (s2->type == SDQUOTE) {
statep->ls_bool = true;
break;
}
}
if (s2 != base)
break;
if (!(s2 = s2->ls_base))
break;
base = s2-- - STATE_BSIZE;
}
break;
case QCHAR:
if (cf & LQCHAR) {
*wp++ = QCHAR;
*wp++ = getsc();
break;
}
/* FALLTHROUGH */
default:
store_char:
*wp++ = CHAR;
*wp++ = c;
}
break;
case SEQUOTE:
if (c == '\'') {
POP_STATE();
*wp++ = CQUOTE;
ignore_backslash_newline--;
} else if (c == '\\') {
if ((c2 = unbksl(true, s_get, s_put)) == -1)
c2 = s_get();
if (c2 == 0)
statep->ls_bool = true;
if (!statep->ls_bool) {
char ts[4];
if ((unsigned int)c2 < 0x100) {
*wp++ = QCHAR;
*wp++ = c2;
} else {
cz = utf_wctomb(ts, c2 - 0x100);
ts[cz] = 0;
for (cz = 0; ts[cz]; ++cz) {
*wp++ = QCHAR;
*wp++ = ts[cz];
}
}
}
} else if (!statep->ls_bool) {
*wp++ = QCHAR;
*wp++ = c;
}
break;
case SSQUOTE:
if (c == '\'') {
POP_STATE();
if ((cf & HEREDOC) || state == SQBRACE)
goto store_char;
*wp++ = CQUOTE;
ignore_backslash_newline--;
} else {
*wp++ = QCHAR;
*wp++ = c;
}
break;
case SDQUOTE:
if (c == '"') {
POP_STATE();
*wp++ = CQUOTE;
} else
goto Subst;
break;
/* $(( ... )) */
case SASPAREN:
if (c == '(')
statep->nparen++;
else if (c == ')') {
statep->nparen--;
if (statep->nparen == 1) {
/* end of EXPRSUB */
POP_SRETRACE();
POP_STATE();
if ((c2 = getsc()) == /*(*/ ')') {
cz = strlen(sp) - 2;
XcheckN(ws, wp, cz);
memcpy(wp, sp + 1, cz);
wp += cz;
afree(sp, ATEMP);
*wp++ = '\0';
break;
} else {
Source *s;
ungetsc(c2);
/*
* mismatched parenthesis -
* assume we were really
* parsing a $(...) expression
*/
--wp;
s = pushs(SREREAD,
source->areap);
s->start = s->str =
s->u.freeme = sp;
s->next = source;
source = s;
goto subst_command;
}
}
}
/* reuse existing state machine */
goto Sbase2;
case SQBRACE:
if (c == '\\') {
/*
* perform POSIX "quote removal" if the back-
* slash is "special", i.e. same cases as the
* {case '\\':} in Subst: plus closing brace;
* in mksh code "quote removal" on '\c' means
* write QCHAR+c, otherwise CHAR+\+CHAR+c are
* emitted (in heredocquote:)
*/
if ((c = getsc()) == '"' || c == '\\' ||
c == '$' || c == '`' || c == /*{*/'}')
goto store_qchar;
goto heredocquote;
}
goto common_SQBRACE;
case SBRACE:
if (c == '\'')
goto open_ssquote_unless_heredoc;
else if (c == '\\')
goto getsc_qchar;
common_SQBRACE:
if (c == '"')
goto open_sdquote;
else if (c == '$')
goto subst_dollar_ex;
else if (c == '`')
goto subst_gravis;
else if (c != /*{*/ '}')
goto store_char;
POP_STATE();
*wp++ = CSUBST;
*wp++ = /*{*/ '}';
break;
/* Same as SBASE, except (,|,) treated specially */
case STBRACEKORN:
if (c == '|')
*wp++ = SPAT;
else if (c == '(') {
*wp++ = OPAT;
/* simile for @ */
*wp++ = ' ';
PUSH_STATE(SPATTERN);
} else /* FALLTHROUGH */
case STBRACEBOURNE:
if (c == /*{*/ '}') {
POP_STATE();
*wp++ = CSUBST;
*wp++ = /*{*/ '}';
} else
goto Sbase1;
break;
case SBQUOTE:
if (c == '`') {
*wp++ = 0;
POP_STATE();
} else if (c == '\\') {
switch (c = getsc()) {
case 0:
/* trailing \ is lost */
break;
case '\\':
case '$': case '`':
*wp++ = c;
break;
case '"':
if (statep->ls_bool) {
*wp++ = c;
break;
}
/* FALLTHROUGH */
default:
*wp++ = '\\';
*wp++ = c;
break;
}
} else
*wp++ = c;
break;
/* ONEWORD */
case SWORD:
goto Subst;
/* LETEXPR: (( ... )) */
case SLETPAREN:
if (c == /*(*/ ')') {
if (statep->nparen > 0)
--statep->nparen;
else if ((c2 = getsc()) == /*(*/ ')') {
c = 0;
*wp++ = CQUOTE;
goto Done;
} else {
Source *s;
ungetsc(c2);
/*
* mismatched parenthesis -
* assume we were really
* parsing a (...) expression
*/
*wp = EOS;
sp = Xstring(ws, wp);
dp = wdstrip(sp, WDS_KEEPQ);
s = pushs(SREREAD, source->areap);
s->start = s->str = s->u.freeme = dp;
s->next = source;
source = s;
return ('('/*)*/);
}
} else if (c == '(')
/*
* parentheses inside quotes and
* backslashes are lost, but AT&T ksh
* doesn't count them either
*/
++statep->nparen;
goto Sbase2;
/* <<, <<-, <<< delimiter */
case SHEREDELIM:
/*
* here delimiters need a special case since
* $ and `...` are not to be treated specially
*/
switch (c) {
case '\\':
if ((c = getsc())) {
/* trailing \ is lost */
*wp++ = QCHAR;
*wp++ = c;
}
break;
case '\'':
goto open_ssquote_unless_heredoc;
case '$':
if ((c2 = getsc()) == '\'') {
open_sequote:
*wp++ = OQUOTE;
ignore_backslash_newline++;
PUSH_STATE(SEQUOTE);
statep->ls_bool = false;
break;
} else if (c2 == '"') {
/* FALLTHROUGH */
case '"':
state = statep->type = SHEREDQUOTE;
PUSH_SRETRACE();
break;
}
ungetsc(c2);
/* FALLTHROUGH */
default:
*wp++ = CHAR;
*wp++ = c;
}
break;
/* " in <<, <<-, <<< delimiter */
case SHEREDQUOTE:
if (c != '"')
goto Subst;
POP_SRETRACE();
dp = strnul(sp) - 1;
/* remove the trailing double quote */
*dp = '\0';
/* store the quoted string */
*wp++ = OQUOTE;
XcheckN(ws, wp, (dp - sp));
dp = sp;
while ((c = *dp++)) {
if (c == '\\') {
switch ((c = *dp++)) {
case '\\':
case '"':
case '$':
case '`':
break;
default:
*wp++ = CHAR;
*wp++ = '\\';
break;
}
}
*wp++ = CHAR;
*wp++ = c;
}
afree(sp, ATEMP);
*wp++ = CQUOTE;
state = statep->type = SHEREDELIM;
break;
/* in *(...|...) pattern (*+?@!) */
case SPATTERN:
if (c == /*(*/ ')') {
*wp++ = CPAT;
POP_STATE();
} else if (c == '|') {
*wp++ = SPAT;
} else if (c == '(') {
*wp++ = OPAT;
/* simile for @ */
*wp++ = ' ';
PUSH_STATE(SPATTERN);
} else
goto Sbase1;
break;
}
}
Done:
Xcheck(ws, wp);
if (statep != &states[1])
/* XXX figure out what is missing */
yyerror("no closing quote\n");
/* This done to avoid tests for SHEREDELIM wherever SBASE tested */
if (state == SHEREDELIM)
state = SBASE;
dp = Xstring(ws, wp);
if (state == SBASE && (
#ifndef MKSH_LEGACY_MODE
(c == '&' && !Flag(FSH) && !Flag(FPOSIX)) ||
#endif
c == '<' || c == '>')) {
struct ioword *iop = alloc(sizeof(struct ioword), ATEMP);
if (Xlength(ws, wp) == 0)
iop->unit = c == '<' ? 0 : 1;
else for (iop->unit = 0, c2 = 0; c2 < Xlength(ws, wp); c2 += 2) {
if (dp[c2] != CHAR)
goto no_iop;
if (!ksh_isdigit(dp[c2 + 1]))
goto no_iop;
iop->unit = (iop->unit * 10) + dp[c2 + 1] - '0';
}
if (iop->unit >= FDBASE)
goto no_iop;
if (c == '&') {
if ((c2 = getsc()) != '>') {
ungetsc(c2);
goto no_iop;
}
c = c2;
iop->flag = IOBASH;
} else
iop->flag = 0;
c2 = getsc();
/* <<, >>, <> are ok, >< is not */
if (c == c2 || (c == '<' && c2 == '>')) {
iop->flag |= c == c2 ?
(c == '>' ? IOCAT : IOHERE) : IORDWR;
if (iop->flag == IOHERE) {
if ((c2 = getsc()) == '-') {
iop->flag |= IOSKIP;
c2 = getsc();
} else if (c2 == '<')
iop->flag |= IOHERESTR;
ungetsc(c2);
if (c2 == '\n')
iop->flag |= IONDELIM;
}
} else if (c2 == '&')
iop->flag |= IODUP | (c == '<' ? IORDUP : 0);
else {
iop->flag |= c == '>' ? IOWRITE : IOREAD;
if (c == '>' && c2 == '|')
iop->flag |= IOCLOB;
else
ungetsc(c2);
}
iop->name = NULL;
iop->delim = NULL;
iop->heredoc = NULL;
/* free word */
Xfree(ws, wp);
yylval.iop = iop;
return (REDIR);
no_iop:
afree(iop, ATEMP);
}
if (wp == dp && state == SBASE) {
/* free word */
Xfree(ws, wp);
/* no word, process LEX1 character */
if ((c == '|') || (c == '&') || (c == ';') || (c == '('/*)*/)) {
if ((c2 = getsc()) == c)
c = (c == ';') ? BREAK :
(c == '|') ? LOGOR :
(c == '&') ? LOGAND :
/* c == '(' ) */ MDPAREN;
else if (c == '|' && c2 == '&')
c = COPROC;
else if (c == ';' && c2 == '|')
c = BRKEV;
else if (c == ';' && c2 == '&')
c = BRKFT;
else
ungetsc(c2);
#ifndef MKSH_SMALL
if (c == BREAK) {
if ((c2 = getsc()) == '&')
c = BRKEV;
else
ungetsc(c2);
}
#endif
} else if (c == '\n') {
gethere(false);
if (cf & CONTIN)
goto Again;
} else if (c == '\0')
/* need here strings at EOF */
gethere(true);
return (c);
}
/* terminate word */
*wp++ = EOS;
yylval.cp = Xclose(ws, wp);
if (state == SWORD || state == SLETPAREN
/* XXX ONEWORD? */)
return (LWORD);
/* unget terminator */
ungetsc(c);
/*
* note: the alias-vs-function code below depends on several
* interna: starting from here, source->str is not modified;
* the way getsc() and ungetsc() operate; etc.
*/
/* copy word to unprefixed string ident */
sp = yylval.cp;
dp = ident;
if ((cf & HEREDELIM) && (sp[1] == '<'))
while ((dp - ident) < IDENT) {
if ((c = *sp++) == CHAR)
*dp++ = *sp++;
else if ((c != OQUOTE) && (c != CQUOTE))
break;
}
else
while ((dp - ident) < IDENT && (c = *sp++) == CHAR)
*dp++ = *sp++;
/* Make sure the ident array stays '\0' padded */
memset(dp, 0, (ident + IDENT) - dp + 1);
if (c != EOS)
/* word is not unquoted */
*ident = '\0';
if (*ident != '\0' && (cf & (KEYWORD | ALIAS))) {
struct tbl *p;
uint32_t h = hash(ident);
if ((cf & KEYWORD) && (p = ktsearch(&keywords, ident, h)) &&
(!(cf & ESACONLY) || p->val.i == ESAC ||
p->val.i == /*{*/ '}')) {
afree(yylval.cp, ATEMP);
return (p->val.i);
}
if ((cf & ALIAS) && (p = ktsearch(&aliases, ident, h)) &&
(p->flag & ISSET)) {
/*
* this still points to the same character as the
* ungetsc'd terminator from above
*/
const char *cp = source->str;
/* prefer POSIX but not Korn functions over aliases */
while (*cp == ' ' || *cp == '\t')
/*
* this is like getsc() without skipping
* over Source boundaries (including not
* parsing ungetsc'd characters that got
* pushed into an SREREAD) which is what
* we want here anyway: find out whether
* the alias name is followed by a POSIX
* function definition (only the opening
* parenthesis is checked though)
*/
++cp;
/* prefer functions over aliases */
if (cp[0] != '(' || cp[1] != ')') {
Source *s = source;
while (s && (s->flags & SF_HASALIAS))
if (s->u.tblp == p)
return (LWORD);
else
s = s->next;
/* push alias expansion */
s = pushs(SALIAS, source->areap);
s->start = s->str = p->val.s;
s->u.tblp = p;
s->flags |= SF_HASALIAS;
s->next = source;
if (source->type == SEOF) {
/* prevent infinite recursion at EOS */
source->u.tblp = p;
source->flags |= SF_HASALIAS;
}
source = s;
afree(yylval.cp, ATEMP);
goto Again;
}
}
}
return (LWORD);
}
static void
gethere(bool iseof)
{
struct ioword **p;
for (p = heres; p < herep; p++)
if (iseof && !((*p)->flag & IOHERESTR))
/* only here strings at EOF */
return;
else
readhere(*p);
herep = heres;
}
/*
* read "<<word" text into temp file
*/
static void
readhere(struct ioword *iop)
{
int c;
const char *eof, *eofp;
XString xs;
char *xp;
int xpos;
if (iop->flag & IOHERESTR) {
/* process the here string */
iop->heredoc = xp = evalstr(iop->delim, DOBLANK);
xpos = strlen(xp) - 1;
memmove(xp, xp + 1, xpos);
xp[xpos] = '\n';
return;
}
eof = iop->flag & IONDELIM ? "<<" : evalstr(iop->delim, 0);
if (!(iop->flag & IOEVAL))
ignore_backslash_newline++;
Xinit(xs, xp, 256, ATEMP);
heredoc_read_line:
/* beginning of line */
eofp = eof;
xpos = Xsavepos(xs, xp);
if (iop->flag & IOSKIP) {
/* skip over leading tabs */
while ((c = getsc()) == '\t')
/* nothing */;
goto heredoc_parse_char;
}
heredoc_read_char:
c = getsc();
heredoc_parse_char:
/* compare with here document marker */
if (!*eofp) {
/* end of here document marker, what to do? */
switch (c) {
case /*(*/ ')':
if (!subshell_nesting_type)
/*-
* not allowed outside $(...) or (...)
* => mismatch
*/
break;
/* allow $(...) or (...) to close here */
ungetsc(/*(*/ ')');
/* FALLTHROUGH */
case 0:
/*
* Allow EOF here to commands without trailing
* newlines (mksh -c '...') will work as well.
*/
case '\n':
/* Newline terminates here document marker */
goto heredoc_found_terminator;
}
} else if (c == *eofp++)
/* store; then read and compare next character */
goto heredoc_store_and_loop;
/* nope, mismatch; read until end of line */
while (c != '\n') {
if (!c)
/* oops, reached EOF */
yyerror("%s '%s' unclosed\n", "here document", eof);
/* store character */
Xcheck(xs, xp);
Xput(xs, xp, c);
/* read next character */
c = getsc();
}
/* we read a newline as last character */
heredoc_store_and_loop:
/* store character */
Xcheck(xs, xp);
Xput(xs, xp, c);
if (c == '\n')
goto heredoc_read_line;
goto heredoc_read_char;
heredoc_found_terminator:
/* jump back to saved beginning of line */
xp = Xrestpos(xs, xp, xpos);
/* terminate, close and store */
Xput(xs, xp, '\0');
iop->heredoc = Xclose(xs, xp);
if (!(iop->flag & IOEVAL))
ignore_backslash_newline--;
}
void
yyerror(const char *fmt, ...)
{
va_list va;
/* pop aliases and re-reads */
while (source->type == SALIAS || source->type == SREREAD)
source = source->next;
/* zap pending input */
source->str = null;
error_prefix(true);
va_start(va, fmt);
shf_vfprintf(shl_out, fmt, va);
va_end(va);
errorfz();
}
/*
* input for yylex with alias expansion
*/
Source *
pushs(int type, Area *areap)
{
Source *s;
s = alloc(sizeof(Source), areap);
memset(s, 0, sizeof(Source));
s->type = type;
s->str = null;
s->areap = areap;
if (type == SFILE || type == SSTDIN)
XinitN(s->xs, 256, s->areap);
return (s);
}
static int
getsc_uu(void)
{
Source *s = source;
int c;
while ((c = *s->str++) == 0) {
/* return 0 for EOF by default */
s->str = NULL;
switch (s->type) {
case SEOF:
s->str = null;
return (0);
case SSTDIN:
case SFILE:
getsc_line(s);
break;
case SWSTR:
break;
case SSTRING:
case SSTRINGCMDLINE:
break;
case SWORDS:
s->start = s->str = *s->u.strv++;
s->type = SWORDSEP;
break;
case SWORDSEP:
if (*s->u.strv == NULL) {
s->start = s->str = "\n";
s->type = SEOF;
} else {
s->start = s->str = " ";
s->type = SWORDS;
}
break;
case SALIAS:
if (s->flags & SF_ALIASEND) {
/* pass on an unused SF_ALIAS flag */
source = s->next;
source->flags |= s->flags & SF_ALIAS;
s = source;
} else if (*s->u.tblp->val.s &&
(c = strnul(s->u.tblp->val.s)[-1], ksh_isspace(c))) {
/* pop source stack */
source = s = s->next;
/*
* Note that this alias ended with a
* space, enabling alias expansion on
* the following word.
*/
s->flags |= SF_ALIAS;
} else {
/*
* At this point, we need to keep the current
* alias in the source list so recursive
* aliases can be detected and we also need to
* return the next character. Do this by
* temporarily popping the alias to get the
* next character and then put it back in the
* source list with the SF_ALIASEND flag set.
*/
/* pop source stack */
source = s->next;
source->flags |= s->flags & SF_ALIAS;
c = getsc_uu();
if (c) {
s->flags |= SF_ALIASEND;
s->ugbuf[0] = c; s->ugbuf[1] = '\0';
s->start = s->str = s->ugbuf;
s->next = source;
source = s;
} else {
s = source;
/* avoid reading EOF twice */
s->str = NULL;
break;
}
}
continue;
case SREREAD:
if (s->start != s->ugbuf)
/* yuck */
afree(s->u.freeme, ATEMP);
source = s = s->next;
continue;
}
if (s->str == NULL) {
s->type = SEOF;
s->start = s->str = null;
return ('\0');
}
if (s->flags & SF_ECHO) {
shf_puts(s->str, shl_out);
shf_flush(shl_out);
}
}
return (c);
}
static void
getsc_line(Source *s)
{
char *xp = Xstring(s->xs, xp), *cp;
bool interactive = Flag(FTALKING) && s->type == SSTDIN;
bool have_tty = tobool(interactive && (s->flags & SF_TTY));
/* Done here to ensure nothing odd happens when a timeout occurs */
XcheckN(s->xs, xp, LINE);
*xp = '\0';
s->start = s->str = xp;
if (have_tty && ksh_tmout) {
ksh_tmout_state = TMOUT_READING;
alarm(ksh_tmout);
}
if (interactive)
change_winsz();
#ifndef MKSH_NO_CMDLINE_EDITING
if (have_tty && (
#if !MKSH_S_NOVI
Flag(FVI) ||
#endif
Flag(FEMACS) || Flag(FGMACS))) {
int nread;
nread = x_read(xp);
if (nread < 0)
/* read error */
nread = 0;
xp[nread] = '\0';
xp += nread;
} else
#endif
{
if (interactive)
pprompt(prompt, 0);
else
s->line++;
while (/* CONSTCOND */ 1) {
char *p = shf_getse(xp, Xnleft(s->xs, xp), s->u.shf);
if (!p && shf_error(s->u.shf) &&
shf_errno(s->u.shf) == EINTR) {
shf_clearerr(s->u.shf);
if (trap)
runtraps(0);
continue;
}
if (!p || (xp = p, xp[-1] == '\n'))
break;
/* double buffer size */
/* move past NUL so doubling works... */
xp++;
XcheckN(s->xs, xp, Xlength(s->xs, xp));
/* ...and move back again */
xp--;
}
/*
* flush any unwanted input so other programs/builtins
* can read it. Not very optimal, but less error prone
* than flushing else where, dealing with redirections,
* etc.
* TODO: reduce size of shf buffer (~128?) if SSTDIN
*/
if (s->type == SSTDIN)
shf_flush(s->u.shf);
}
/*
* XXX: temporary kludge to restore source after a
* trap may have been executed.
*/
source = s;
if (have_tty && ksh_tmout) {
ksh_tmout_state = TMOUT_EXECUTING;
alarm(0);
}
cp = Xstring(s->xs, xp);
s->start = s->str = cp;
strip_nuls(Xstring(s->xs, xp), Xlength(s->xs, xp));
/* Note: if input is all nulls, this is not eof */
if (Xlength(s->xs, xp) == 0) {
/* EOF */
if (s->type == SFILE)
shf_fdclose(s->u.shf);
s->str = NULL;
} else if (interactive && *s->str &&
(cur_prompt != PS1 || !ctype(*s->str, C_IFS | C_IFSWS))) {
histsave(&s->line, s->str, true, true);
#if !defined(MKSH_SMALL) && HAVE_PERSISTENT_HISTORY
} else if (interactive && cur_prompt == PS1) {
cp = Xstring(s->xs, xp);
while (*cp && ctype(*cp, C_IFSWS))
++cp;
if (!*cp)
histsync();
#endif
}
if (interactive)
set_prompt(PS2, NULL);
}
void
set_prompt(int to, Source *s)
{
cur_prompt = to;
switch (to) {
/* command */
case PS1:
/*
* Substitute ! and !! here, before substitutions are done
* so ! in expanded variables are not expanded.
* NOTE: this is not what AT&T ksh does (it does it after
* substitutions, POSIX doesn't say which is to be done.
*/
{
struct shf *shf;
char * volatile ps1;
Area *saved_atemp;
ps1 = str_val(global("PS1"));
shf = shf_sopen(NULL, strlen(ps1) * 2,
SHF_WR | SHF_DYNAMIC, NULL);
while (*ps1)
if (*ps1 != '!' || *++ps1 == '!')
shf_putchar(*ps1++, shf);
else
shf_fprintf(shf, "%d",
s ? s->line + 1 : 0);
ps1 = shf_sclose(shf);
saved_atemp = ATEMP;
newenv(E_ERRH);
if (kshsetjmp(e->jbuf)) {
prompt = safe_prompt;
/*
* Don't print an error - assume it has already
* been printed. Reason is we may have forked
* to run a command and the child may be
* unwinding its stack through this code as it
* exits.
*/
} else {
char *cp = substitute(ps1, 0);
strdupx(prompt, cp, saved_atemp);
}
quitenv(NULL);
}
break;
/* command continuation */
case PS2:
prompt = str_val(global("PS2"));
break;
}
}
int
pprompt(const char *cp, int ntruncate)
{
char delimiter = 0;
bool doprint = (ntruncate != -1);
bool indelimit = false;
int columns = 0, lines = 0;
/*
* Undocumented AT&T ksh feature:
* If the second char in the prompt string is \r then the first
* char is taken to be a non-printing delimiter and any chars
* between two instances of the delimiter are not considered to
* be part of the prompt length
*/
if (*cp && cp[1] == '\r') {
delimiter = *cp;
cp += 2;
}
for (; *cp; cp++) {
if (indelimit && *cp != delimiter)
;
else if (*cp == '\n' || *cp == '\r') {
lines += columns / x_cols + ((*cp == '\n') ? 1 : 0);
columns = 0;
} else if (*cp == '\t') {
columns = (columns | 7) + 1;
} else if (*cp == '\b') {
if (columns > 0)
columns--;
} else if (*cp == delimiter)
indelimit = !indelimit;
else if (UTFMODE && ((unsigned char)*cp > 0x7F)) {
const char *cp2;
columns += utf_widthadj(cp, &cp2);
if (doprint && (indelimit ||
(ntruncate < (x_cols * lines + columns))))
shf_write(cp, cp2 - cp, shl_out);
cp = cp2 - /* loop increment */ 1;
continue;
} else
columns++;
if (doprint && (*cp != delimiter) &&
(indelimit || (ntruncate < (x_cols * lines + columns))))
shf_putc(*cp, shl_out);
}
if (doprint)
shf_flush(shl_out);
return (x_cols * lines + columns);
}
/*
* Read the variable part of a ${...} expression (i.e. up to but not
* including the :[-+?=#%] or close-brace).
*/
static char *
get_brace_var(XString *wsp, char *wp)
{
char c;
enum parse_state {
PS_INITIAL, PS_SAW_HASH, PS_IDENT,
PS_NUMBER, PS_VAR1
} state = PS_INITIAL;
while (/* CONSTCOND */ 1) {
c = getsc();
/* State machine to figure out where the variable part ends. */
switch (state) {
case PS_INITIAL:
if (c == '#' || c == '!' || c == '%') {
state = PS_SAW_HASH;
break;
}
/* FALLTHROUGH */
case PS_SAW_HASH:
if (ksh_isalphx(c))
state = PS_IDENT;
else if (ksh_isdigit(c))
state = PS_NUMBER;
else if (c == '#') {
if (state == PS_SAW_HASH) {
char c2;
c2 = getsc();
ungetsc(c2);
if (c2 != /*{*/ '}') {
ungetsc(c);
goto out;
}
}
state = PS_VAR1;
} else if (ctype(c, C_VAR1))
state = PS_VAR1;
else
goto out;
break;
case PS_IDENT:
if (!ksh_isalnux(c)) {
if (c == '[') {
char *tmp, *p;
if (!arraysub(&tmp))
yyerror("missing ]\n");
*wp++ = c;
for (p = tmp; *p; ) {
Xcheck(*wsp, wp);
*wp++ = *p++;
}
afree(tmp, ATEMP);
/* the ] */
c = getsc();
}
goto out;
}
break;
case PS_NUMBER:
if (!ksh_isdigit(c))
goto out;
break;
case PS_VAR1:
goto out;
}
Xcheck(*wsp, wp);
*wp++ = c;
}
out:
/* end of variable part */
*wp++ = '\0';
ungetsc(c);
return (wp);
}
/*
* Save an array subscript - returns true if matching bracket found, false
* if eof or newline was found.
* (Returned string double null terminated)
*/
static bool
arraysub(char **strp)
{
XString ws;
char *wp, c;
/* we are just past the initial [ */
unsigned int depth = 1;
Xinit(ws, wp, 32, ATEMP);
do {
c = getsc();
Xcheck(ws, wp);
*wp++ = c;
if (c == '[')
depth++;
else if (c == ']')
depth--;
} while (depth > 0 && c && c != '\n');
*wp++ = '\0';
*strp = Xclose(ws, wp);
return (tobool(depth == 0));
}
/* Unget a char: handles case when we are already at the start of the buffer */
static void
ungetsc(int c)
{
struct sretrace_info *rp = retrace_info;
if (backslash_skip)
backslash_skip--;
/* Don't unget EOF... */
if (source->str == null && c == '\0')
return;
while (rp) {
if (Xlength(rp->xs, rp->xp))
rp->xp--;
rp = rp->next;
}
ungetsc_i(c);
}
static void
ungetsc_i(int c)
{
if (source->str > source->start)
source->str--;
else {
Source *s;
s = pushs(SREREAD, source->areap);
s->ugbuf[0] = c; s->ugbuf[1] = '\0';
s->start = s->str = s->ugbuf;
s->next = source;
source = s;
}
}
/* Called to get a char that isn't a \newline sequence. */
static int
getsc_bn(void)
{
int c, c2;
if (ignore_backslash_newline)
return (o_getsc_u());
if (backslash_skip == 1) {
backslash_skip = 2;
return (o_getsc_u());
}
backslash_skip = 0;
while (/* CONSTCOND */ 1) {
c = o_getsc_u();
if (c == '\\') {
if ((c2 = o_getsc_u()) == '\n')
/* ignore the \newline; get the next char... */
continue;
ungetsc_i(c2);
backslash_skip = 1;
}
return (c);
}
}
void
yyskiputf8bom(void)
{
int c;
if ((unsigned char)(c = o_getsc_u()) != 0xEF) {
ungetsc_i(c);
return;
}
if ((unsigned char)(c = o_getsc_u()) != 0xBB) {
ungetsc_i(c);
ungetsc_i(0xEF);
return;
}
if ((unsigned char)(c = o_getsc_u()) != 0xBF) {
ungetsc_i(c);
ungetsc_i(0xBB);
ungetsc_i(0xEF);
return;
}
UTFMODE |= 8;
}
static Lex_state *
push_state_i(State_info *si, Lex_state *old_end)
{
Lex_state *news = alloc2(STATE_BSIZE, sizeof(Lex_state), ATEMP);
news[0].ls_base = old_end;
si->base = &news[0];
si->end = &news[STATE_BSIZE];
return (&news[1]);
}
static Lex_state *
pop_state_i(State_info *si, Lex_state *old_end)
{
Lex_state *old_base = si->base;
si->base = old_end->ls_base - STATE_BSIZE;
si->end = old_end->ls_base;
afree(old_base, ATEMP);
return (si->base + STATE_BSIZE - 1);
}
static int
s_get(void)
{
return (getsc());
}
static void
s_put(int c)
{
ungetsc(c);
}
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