0,0 → 1,1559 |
/* $NetBSD: parser.c,v 1.45 2000/07/27 04:09:27 cgd 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. All advertising materials mentioning features or use of this software |
* must display the following acknowledgement: |
* This product includes software developed by the University of |
* California, Berkeley and its contributors. |
* 4. 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[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95"; |
#else |
__RCSID("$NetBSD: parser.c,v 1.45 2000/07/27 04:09:27 cgd Exp $"); |
#endif |
#endif /* not lint */ |
|
#include <stdlib.h> |
|
#include "shell.h" |
#include "parser.h" |
#include "nodes.h" |
#include "expand.h" /* defines rmescapes() */ |
#include "redir.h" /* defines copyfd() */ |
#include "syntax.h" |
#include "options.h" |
#include "input.h" |
#include "output.h" |
#include "var.h" |
#include "error.h" |
#include "memalloc.h" |
#include "mystring.h" |
#include "alias.h" |
#include "show.h" |
#ifndef SMALL |
#include "myhistedit.h" |
#endif |
|
/* |
* Shell command parser. |
*/ |
|
#define EOFMARKLEN 79 |
|
/* values returned by readtoken */ |
#include "token.h" |
|
|
|
struct heredoc { |
struct heredoc *next; /* next here document in list */ |
union node *here; /* redirection node */ |
char *eofmark; /* string indicating end of input */ |
int striptabs; /* if set, strip leading tabs */ |
}; |
|
|
|
struct heredoc *heredoclist; /* list of here documents to read */ |
int parsebackquote; /* nonzero if we are inside backquotes */ |
int doprompt; /* if set, prompt the user */ |
int needprompt; /* true if interactive and at start of line */ |
int lasttoken; /* last token read */ |
MKINIT int tokpushback; /* last token pushed back */ |
char *wordtext; /* text of last word returned by readtoken */ |
MKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */ |
struct nodelist *backquotelist; |
union node *redirnode; |
struct heredoc *heredoc; |
int quoteflag; /* set if (part of) last token was quoted */ |
int startlinno; /* line # where last token started */ |
|
|
STATIC union node *list (int); |
STATIC union node *andor (void); |
STATIC union node *pipeline (void); |
STATIC union node *command (void); |
STATIC union node *simplecmd (union node **, union node *); |
STATIC union node *makename (void); |
STATIC void parsefname (void); |
STATIC void parseheredoc (void); |
STATIC int peektoken (void); |
STATIC int readtoken (void); |
STATIC int xxreadtoken (void); |
STATIC int readtoken1 (int, char const *, char *, int); |
STATIC int noexpand (char *); |
STATIC void synexpect (int) __attribute__((noreturn)); |
STATIC void synerror (const char *) __attribute__((noreturn)); |
STATIC void setprompt (int); |
|
|
/* |
* Read and parse a command. Returns NEOF on end of file. (NULL is a |
* valid parse tree indicating a blank line.) |
*/ |
|
union node * |
parsecmd(int interact) |
{ |
int t; |
|
doprompt = interact; |
if (doprompt) |
setprompt(1); |
else |
setprompt(0); |
needprompt = 0; |
t = readtoken(); |
if (t == TEOF) |
return NEOF; |
if (t == TNL) |
return NULL; |
tokpushback++; |
return list(1); |
} |
|
|
STATIC union node * |
list(nlflag) |
int nlflag; |
{ |
union node *n1, *n2, *n3; |
int tok; |
|
checkkwd = 2; |
if (nlflag == 0 && tokendlist[peektoken()]) |
return NULL; |
n1 = NULL; |
for (;;) { |
n2 = andor(); |
tok = readtoken(); |
if (tok == TBACKGND) { |
if (n2->type == NCMD || n2->type == NPIPE) { |
n2->ncmd.backgnd = 1; |
} else if (n2->type == NREDIR) { |
n2->type = NBACKGND; |
} else { |
n3 = (union node *)stalloc(sizeof (struct nredir)); |
n3->type = NBACKGND; |
n3->nredir.n = n2; |
n3->nredir.redirect = NULL; |
n2 = n3; |
} |
} |
if (n1 == NULL) { |
n1 = n2; |
} |
else { |
n3 = (union node *)stalloc(sizeof (struct nbinary)); |
n3->type = NSEMI; |
n3->nbinary.ch1 = n1; |
n3->nbinary.ch2 = n2; |
n1 = n3; |
} |
switch (tok) { |
case TBACKGND: |
case TSEMI: |
tok = readtoken(); |
/* fall through */ |
case TNL: |
if (tok == TNL) { |
parseheredoc(); |
if (nlflag) |
return n1; |
} else { |
tokpushback++; |
} |
checkkwd = 2; |
if (tokendlist[peektoken()]) |
return n1; |
break; |
case TEOF: |
if (heredoclist) |
parseheredoc(); |
else |
pungetc(); /* push back EOF on input */ |
return n1; |
default: |
if (nlflag) |
synexpect(-1); |
tokpushback++; |
return n1; |
} |
} |
} |
|
|
|
STATIC union node * |
andor() { |
union node *n1, *n2, *n3; |
int t; |
|
checkkwd = 1; |
n1 = pipeline(); |
for (;;) { |
if ((t = readtoken()) == TAND) { |
t = NAND; |
} else if (t == TOR) { |
t = NOR; |
} else { |
tokpushback++; |
return n1; |
} |
checkkwd = 2; |
n2 = pipeline(); |
n3 = (union node *)stalloc(sizeof (struct nbinary)); |
n3->type = t; |
n3->nbinary.ch1 = n1; |
n3->nbinary.ch2 = n2; |
n1 = n3; |
} |
} |
|
|
|
STATIC union node * |
pipeline() { |
union node *n1, *n2, *pipenode; |
struct nodelist *lp, *prev; |
int negate; |
|
negate = 0; |
TRACE(("pipeline: entered\n")); |
if (readtoken() == TNOT) { |
negate = !negate; |
checkkwd = 1; |
} else |
tokpushback++; |
n1 = command(); |
if (readtoken() == TPIPE) { |
pipenode = (union node *)stalloc(sizeof (struct npipe)); |
pipenode->type = NPIPE; |
pipenode->npipe.backgnd = 0; |
lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); |
pipenode->npipe.cmdlist = lp; |
lp->n = n1; |
do { |
prev = lp; |
lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); |
checkkwd = 2; |
lp->n = command(); |
prev->next = lp; |
} while (readtoken() == TPIPE); |
lp->next = NULL; |
n1 = pipenode; |
} |
tokpushback++; |
if (negate) { |
n2 = (union node *)stalloc(sizeof (struct nnot)); |
n2->type = NNOT; |
n2->nnot.com = n1; |
return n2; |
} else |
return n1; |
} |
|
|
|
STATIC union node * |
command() { |
union node *n1, *n2; |
union node *ap, **app; |
union node *cp, **cpp; |
union node *redir, **rpp; |
int t; |
|
redir = NULL; |
n1 = NULL; |
rpp = &redir; |
|
/* Check for redirection which may precede command */ |
while (readtoken() == TREDIR) { |
*rpp = n2 = redirnode; |
rpp = &n2->nfile.next; |
parsefname(); |
} |
tokpushback++; |
|
switch (readtoken()) { |
case TIF: |
n1 = (union node *)stalloc(sizeof (struct nif)); |
n1->type = NIF; |
n1->nif.test = list(0); |
if (readtoken() != TTHEN) |
synexpect(TTHEN); |
n1->nif.ifpart = list(0); |
n2 = n1; |
while (readtoken() == TELIF) { |
n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif)); |
n2 = n2->nif.elsepart; |
n2->type = NIF; |
n2->nif.test = list(0); |
if (readtoken() != TTHEN) |
synexpect(TTHEN); |
n2->nif.ifpart = list(0); |
} |
if (lasttoken == TELSE) |
n2->nif.elsepart = list(0); |
else { |
n2->nif.elsepart = NULL; |
tokpushback++; |
} |
if (readtoken() != TFI) |
synexpect(TFI); |
checkkwd = 1; |
break; |
case TWHILE: |
case TUNTIL: { |
int got; |
n1 = (union node *)stalloc(sizeof (struct nbinary)); |
n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL; |
n1->nbinary.ch1 = list(0); |
if ((got=readtoken()) != TDO) { |
TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : "")); |
synexpect(TDO); |
} |
n1->nbinary.ch2 = list(0); |
if (readtoken() != TDONE) |
synexpect(TDONE); |
checkkwd = 1; |
break; |
} |
case TFOR: |
if (readtoken() != TWORD || quoteflag || ! goodname(wordtext)) |
synerror("Bad for loop variable"); |
n1 = (union node *)stalloc(sizeof (struct nfor)); |
n1->type = NFOR; |
n1->nfor.var = wordtext; |
if (readtoken() == TWORD && ! quoteflag && equal(wordtext, "in")) { |
app = ≈ |
while (readtoken() == TWORD) { |
n2 = (union node *)stalloc(sizeof (struct narg)); |
n2->type = NARG; |
n2->narg.text = wordtext; |
n2->narg.backquote = backquotelist; |
*app = n2; |
app = &n2->narg.next; |
} |
*app = NULL; |
n1->nfor.args = ap; |
if (lasttoken != TNL && lasttoken != TSEMI) |
synexpect(-1); |
} else { |
static char argvars[5] = {CTLVAR, VSNORMAL|VSQUOTE, |
'@', '=', '\0'}; |
n2 = (union node *)stalloc(sizeof (struct narg)); |
n2->type = NARG; |
n2->narg.text = argvars; |
n2->narg.backquote = NULL; |
n2->narg.next = NULL; |
n1->nfor.args = n2; |
/* |
* Newline or semicolon here is optional (but note |
* that the original Bourne shell only allowed NL). |
*/ |
if (lasttoken != TNL && lasttoken != TSEMI) |
tokpushback++; |
} |
checkkwd = 2; |
if ((t = readtoken()) == TDO) |
t = TDONE; |
else if (t == TBEGIN) |
t = TEND; |
else |
synexpect(-1); |
n1->nfor.body = list(0); |
if (readtoken() != t) |
synexpect(t); |
checkkwd = 1; |
break; |
case TCASE: |
n1 = (union node *)stalloc(sizeof (struct ncase)); |
n1->type = NCASE; |
if (readtoken() != TWORD) |
synexpect(TWORD); |
n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg)); |
n2->type = NARG; |
n2->narg.text = wordtext; |
n2->narg.backquote = backquotelist; |
n2->narg.next = NULL; |
while (readtoken() == TNL); |
if (lasttoken != TWORD || ! equal(wordtext, "in")) |
synerror("expecting \"in\""); |
cpp = &n1->ncase.cases; |
checkkwd = 2, readtoken(); |
do { |
if (lasttoken == TLP) |
readtoken(); |
*cpp = cp = (union node *)stalloc(sizeof (struct nclist)); |
cp->type = NCLIST; |
app = &cp->nclist.pattern; |
for (;;) { |
*app = ap = (union node *)stalloc(sizeof (struct narg)); |
ap->type = NARG; |
ap->narg.text = wordtext; |
ap->narg.backquote = backquotelist; |
if (checkkwd = 2, readtoken() != TPIPE) |
break; |
app = &ap->narg.next; |
readtoken(); |
} |
ap->narg.next = NULL; |
if (lasttoken != TRP) |
synexpect(TRP); |
cp->nclist.body = list(0); |
|
checkkwd = 2; |
if ((t = readtoken()) != TESAC) { |
if (t != TENDCASE) |
synexpect(TENDCASE); |
else |
checkkwd = 2, readtoken(); |
} |
cpp = &cp->nclist.next; |
} while(lasttoken != TESAC); |
*cpp = NULL; |
checkkwd = 1; |
break; |
case TLP: |
n1 = (union node *)stalloc(sizeof (struct nredir)); |
n1->type = NSUBSHELL; |
n1->nredir.n = list(0); |
n1->nredir.redirect = NULL; |
if (readtoken() != TRP) |
synexpect(TRP); |
checkkwd = 1; |
break; |
case TBEGIN: |
n1 = list(0); |
if (readtoken() != TEND) |
synexpect(TEND); |
checkkwd = 1; |
break; |
/* Handle an empty command like other simple commands. */ |
case TSEMI: |
case TAND: |
case TOR: |
case TNL: |
case TEOF: |
case TRP: |
case TBACKGND: |
/* |
* An empty command before a ; doesn't make much sense, and |
* should certainly be disallowed in the case of `if ;'. |
*/ |
if (!redir) |
synexpect(-1); |
case TWORD: |
tokpushback++; |
n1 = simplecmd(rpp, redir); |
return n1; |
default: |
synexpect(-1); |
/* NOTREACHED */ |
} |
|
/* Now check for redirection which may follow command */ |
while (readtoken() == TREDIR) { |
*rpp = n2 = redirnode; |
rpp = &n2->nfile.next; |
parsefname(); |
} |
tokpushback++; |
*rpp = NULL; |
if (redir) { |
if (n1->type != NSUBSHELL) { |
n2 = (union node *)stalloc(sizeof (struct nredir)); |
n2->type = NREDIR; |
n2->nredir.n = n1; |
n1 = n2; |
} |
n1->nredir.redirect = redir; |
} |
|
return n1; |
} |
|
|
STATIC union node * |
simplecmd(rpp, redir) |
union node **rpp, *redir; |
{ |
union node *args, **app; |
union node **orig_rpp = rpp; |
union node *n = NULL; |
|
/* If we don't have any redirections already, then we must reset */ |
/* rpp to be the address of the local redir variable. */ |
if (redir == 0) |
rpp = &redir; |
|
args = NULL; |
app = &args; |
/* |
* We save the incoming value, because we need this for shell |
* functions. There can not be a redirect or an argument between |
* the function name and the open parenthesis. |
*/ |
orig_rpp = rpp; |
|
for (;;) { |
if (readtoken() == TWORD) { |
n = (union node *)stalloc(sizeof (struct narg)); |
n->type = NARG; |
n->narg.text = wordtext; |
n->narg.backquote = backquotelist; |
*app = n; |
app = &n->narg.next; |
} else if (lasttoken == TREDIR) { |
*rpp = n = redirnode; |
rpp = &n->nfile.next; |
parsefname(); /* read name of redirection file */ |
} else if (lasttoken == TLP && app == &args->narg.next |
&& rpp == orig_rpp) { |
/* We have a function */ |
if (readtoken() != TRP) |
synexpect(TRP); |
#ifdef notdef |
if (! goodname(n->narg.text)) |
synerror("Bad function name"); |
#endif |
n->type = NDEFUN; |
checkkwd = 2; |
n->narg.next = command(); |
return n; |
} else { |
tokpushback++; |
break; |
} |
} |
*app = NULL; |
*rpp = NULL; |
n = (union node *)stalloc(sizeof (struct ncmd)); |
n->type = NCMD; |
n->ncmd.backgnd = 0; |
n->ncmd.args = args; |
n->ncmd.redirect = redir; |
return n; |
} |
|
STATIC union node * |
makename() { |
union node *n; |
|
n = (union node *)stalloc(sizeof (struct narg)); |
n->type = NARG; |
n->narg.next = NULL; |
n->narg.text = wordtext; |
n->narg.backquote = backquotelist; |
return n; |
} |
|
void fixredir(union node *n, const char *text, int err) |
{ |
TRACE(("Fix redir %s %d\n", text, err)); |
if (!err) |
n->ndup.vname = NULL; |
|
if (is_digit(text[0]) && text[1] == '\0') |
n->ndup.dupfd = digit_val(text[0]); |
else if (text[0] == '-' && text[1] == '\0') |
n->ndup.dupfd = -1; |
else { |
|
if (err) |
synerror("Bad fd number"); |
else |
n->ndup.vname = makename(); |
} |
} |
|
|
STATIC void |
parsefname() { |
union node *n = redirnode; |
|
if (readtoken() != TWORD) |
synexpect(-1); |
if (n->type == NHERE) { |
struct heredoc *here = heredoc; |
struct heredoc *p; |
int i; |
|
if (quoteflag == 0) |
n->type = NXHERE; |
TRACE(("Here document %d\n", n->type)); |
if (here->striptabs) { |
while (*wordtext == '\t') |
wordtext++; |
} |
if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN) |
synerror("Illegal eof marker for << redirection"); |
rmescapes(wordtext); |
here->eofmark = wordtext; |
here->next = NULL; |
if (heredoclist == NULL) |
heredoclist = here; |
else { |
for (p = heredoclist ; p->next ; p = p->next); |
p->next = here; |
} |
} else if (n->type == NTOFD || n->type == NFROMFD) { |
fixredir(n, wordtext, 0); |
} else { |
n->nfile.fname = makename(); |
} |
} |
|
|
/* |
* Input any here documents. |
*/ |
|
STATIC void |
parseheredoc() { |
struct heredoc *here; |
union node *n; |
|
while (heredoclist) { |
here = heredoclist; |
heredoclist = here->next; |
if (needprompt) { |
setprompt(2); |
needprompt = 0; |
} |
readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX, |
here->eofmark, here->striptabs); |
n = (union node *)stalloc(sizeof (struct narg)); |
n->narg.type = NARG; |
n->narg.next = NULL; |
n->narg.text = wordtext; |
n->narg.backquote = backquotelist; |
here->here->nhere.doc = n; |
} |
} |
|
STATIC int |
peektoken() { |
int t; |
|
t = readtoken(); |
tokpushback++; |
return (t); |
} |
|
STATIC int |
readtoken() { |
int t; |
int savecheckkwd = checkkwd; |
struct alias *ap; |
#ifdef DEBUG |
int alreadyseen = tokpushback; |
#endif |
|
top: |
t = xxreadtoken(); |
|
if (checkkwd) { |
/* |
* eat newlines |
*/ |
if (checkkwd == 2) { |
checkkwd = 0; |
while (t == TNL) { |
parseheredoc(); |
t = xxreadtoken(); |
} |
} else |
checkkwd = 0; |
/* |
* check for keywords and aliases |
*/ |
if (t == TWORD && !quoteflag) |
{ |
const char *const *pp; |
|
for (pp = parsekwd; *pp; pp++) { |
if (**pp == *wordtext && equal(*pp, wordtext)) |
{ |
lasttoken = t = pp - |
parsekwd + KWDOFFSET; |
TRACE(("keyword %s recognized\n", tokname[t])); |
goto out; |
} |
} |
if ((ap = lookupalias(wordtext, 1)) != NULL) { |
pushstring(ap->val, strlen(ap->val), ap); |
checkkwd = savecheckkwd; |
goto top; |
} |
} |
out: |
checkkwd = 0; |
} |
#ifdef DEBUG |
if (!alreadyseen) |
TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); |
else |
TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); |
#endif |
return (t); |
} |
|
|
/* |
* Read the next input token. |
* If the token is a word, we set backquotelist to the list of cmds in |
* backquotes. We set quoteflag to true if any part of the word was |
* quoted. |
* If the token is TREDIR, then we set redirnode to a structure containing |
* the redirection. |
* In all cases, the variable startlinno is set to the number of the line |
* on which the token starts. |
* |
* [Change comment: here documents and internal procedures] |
* [Readtoken shouldn't have any arguments. Perhaps we should make the |
* word parsing code into a separate routine. In this case, readtoken |
* doesn't need to have any internal procedures, but parseword does. |
* We could also make parseoperator in essence the main routine, and |
* have parseword (readtoken1?) handle both words and redirection.] |
*/ |
|
#define RETURN(token) return lasttoken = token |
|
STATIC int |
xxreadtoken() { |
int c; |
|
if (tokpushback) { |
tokpushback = 0; |
return lasttoken; |
} |
if (needprompt) { |
setprompt(2); |
needprompt = 0; |
} |
startlinno = plinno; |
for (;;) { /* until token or start of word found */ |
c = pgetc_macro(); |
if (c == ' ' || c == '\t') |
continue; /* quick check for white space first */ |
switch (c) { |
case ' ': case '\t': |
continue; |
case '#': |
while ((c = pgetc()) != '\n' && c != PEOF); |
pungetc(); |
continue; |
case '\\': |
if (pgetc() == '\n') { |
startlinno = ++plinno; |
if (doprompt) |
setprompt(2); |
else |
setprompt(0); |
continue; |
} |
pungetc(); |
goto breakloop; |
case '\n': |
plinno++; |
needprompt = doprompt; |
RETURN(TNL); |
case PEOF: |
RETURN(TEOF); |
case '&': |
if (pgetc() == '&') |
RETURN(TAND); |
pungetc(); |
RETURN(TBACKGND); |
case '|': |
if (pgetc() == '|') |
RETURN(TOR); |
pungetc(); |
RETURN(TPIPE); |
case ';': |
if (pgetc() == ';') |
RETURN(TENDCASE); |
pungetc(); |
RETURN(TSEMI); |
case '(': |
RETURN(TLP); |
case ')': |
RETURN(TRP); |
default: |
goto breakloop; |
} |
} |
breakloop: |
return readtoken1(c, BASESYNTAX, (char *)NULL, 0); |
#undef RETURN |
} |
|
|
|
/* |
* If eofmark is NULL, read a word or a redirection symbol. If eofmark |
* is not NULL, read a here document. In the latter case, eofmark is the |
* word which marks the end of the document and striptabs is true if |
* leading tabs should be stripped from the document. The argument firstc |
* is the first character of the input token or document. |
* |
* Because C does not have internal subroutines, I have simulated them |
* using goto's to implement the subroutine linkage. The following macros |
* will run code that appears at the end of readtoken1. |
*/ |
|
#define CHECKEND() {goto checkend; checkend_return:;} |
#define PARSEREDIR() {goto parseredir; parseredir_return:;} |
#define PARSESUB() {goto parsesub; parsesub_return:;} |
#define PARSEBACKQOLD() {oldstyle = 1; goto parsebackq; parsebackq_oldreturn:;} |
#define PARSEBACKQNEW() {oldstyle = 0; goto parsebackq; parsebackq_newreturn:;} |
#define PARSEARITH() {goto parsearith; parsearith_return:;} |
|
STATIC int |
readtoken1(firstc, syntax, eofmark, striptabs) |
int firstc; |
char const *syntax; |
char *eofmark; |
int striptabs; |
{ |
int c = firstc; |
char *out; |
int len; |
char line[EOFMARKLEN + 1]; |
struct nodelist *bqlist; |
int quotef; |
int dblquote; |
int varnest; /* levels of variables expansion */ |
int arinest; /* levels of arithmetic expansion */ |
int parenlevel; /* levels of parens in arithmetic */ |
int dqvarnest; /* levels of variables expansion within double quotes */ |
int oldstyle; |
char const *prevsyntax; /* syntax before arithmetic */ |
#if __GNUC__ |
/* Avoid longjmp clobbering */ |
(void) &out; |
(void) "ef; |
(void) &dblquote; |
(void) &varnest; |
(void) &arinest; |
(void) &parenlevel; |
(void) &dqvarnest; |
(void) &oldstyle; |
(void) &prevsyntax; |
(void) &syntax; |
#endif |
|
startlinno = plinno; |
dblquote = 0; |
if (syntax == DQSYNTAX) |
dblquote = 1; |
quotef = 0; |
bqlist = NULL; |
varnest = 0; |
arinest = 0; |
parenlevel = 0; |
dqvarnest = 0; |
|
STARTSTACKSTR(out); |
loop: { /* for each line, until end of word */ |
#if ATTY |
if (c == '\034' && doprompt |
&& attyset() && ! equal(termval(), "emacs")) { |
attyline(); |
if (syntax == BASESYNTAX) |
return readtoken(); |
c = pgetc(); |
goto loop; |
} |
#endif |
CHECKEND(); /* set c to PEOF if at end of here document */ |
for (;;) { /* until end of line or end of word */ |
CHECKSTRSPACE(3, out); /* permit 3 calls to USTPUTC */ |
switch(syntax[c]) { |
case CNL: /* '\n' */ |
if (syntax == BASESYNTAX) |
goto endword; /* exit outer loop */ |
USTPUTC(c, out); |
plinno++; |
if (doprompt) |
setprompt(2); |
else |
setprompt(0); |
c = pgetc(); |
goto loop; /* continue outer loop */ |
case CWORD: |
USTPUTC(c, out); |
break; |
case CCTL: |
if ((eofmark == NULL || dblquote) && |
dqvarnest == 0) |
USTPUTC(CTLESC, out); |
USTPUTC(c, out); |
break; |
case CBACK: /* backslash */ |
c = pgetc(); |
if (c == PEOF) { |
USTPUTC('\\', out); |
pungetc(); |
} else if (c == '\n') { |
if (doprompt) |
setprompt(2); |
else |
setprompt(0); |
} else { |
if (dblquote && c != '\\' && c != '`' && c != '$' |
&& (c != '"' || eofmark != NULL)) |
USTPUTC('\\', out); |
if (SQSYNTAX[c] == CCTL) |
USTPUTC(CTLESC, out); |
else if (eofmark == NULL) |
USTPUTC(CTLQUOTEMARK, out); |
USTPUTC(c, out); |
quotef++; |
} |
break; |
case CSQUOTE: |
if (eofmark == NULL) |
USTPUTC(CTLQUOTEMARK, out); |
syntax = SQSYNTAX; |
break; |
case CDQUOTE: |
if (eofmark == NULL) |
USTPUTC(CTLQUOTEMARK, out); |
syntax = DQSYNTAX; |
dblquote = 1; |
break; |
case CENDQUOTE: |
if (eofmark != NULL && arinest == 0 && |
varnest == 0) { |
USTPUTC(c, out); |
} else { |
if (arinest) { |
syntax = ARISYNTAX; |
dblquote = 0; |
} else if (eofmark == NULL && |
dqvarnest == 0) { |
syntax = BASESYNTAX; |
dblquote = 0; |
} |
quotef++; |
} |
break; |
case CVAR: /* '$' */ |
PARSESUB(); /* parse substitution */ |
break; |
case CENDVAR: /* '}' */ |
if (varnest > 0) { |
varnest--; |
if (dqvarnest > 0) { |
dqvarnest--; |
} |
USTPUTC(CTLENDVAR, out); |
} else { |
USTPUTC(c, out); |
} |
break; |
case CLP: /* '(' in arithmetic */ |
parenlevel++; |
USTPUTC(c, out); |
break; |
case CRP: /* ')' in arithmetic */ |
if (parenlevel > 0) { |
USTPUTC(c, out); |
--parenlevel; |
} else { |
if (pgetc() == ')') { |
if (--arinest == 0) { |
USTPUTC(CTLENDARI, out); |
syntax = prevsyntax; |
if (syntax == DQSYNTAX) |
dblquote = 1; |
else |
dblquote = 0; |
} else |
USTPUTC(')', out); |
} else { |
/* |
* unbalanced parens |
* (don't 2nd guess - no error) |
*/ |
pungetc(); |
USTPUTC(')', out); |
} |
} |
break; |
case CBQUOTE: /* '`' */ |
PARSEBACKQOLD(); |
break; |
case CEOF: |
goto endword; /* exit outer loop */ |
default: |
if (varnest == 0) |
goto endword; /* exit outer loop */ |
USTPUTC(c, out); |
} |
c = pgetc_macro(); |
} |
} |
endword: |
if (syntax == ARISYNTAX) |
synerror("Missing '))'"); |
if (syntax != BASESYNTAX && ! parsebackquote && eofmark == NULL) |
synerror("Unterminated quoted string"); |
if (varnest != 0) { |
startlinno = plinno; |
synerror("Missing '}'"); |
} |
USTPUTC('\0', out); |
len = out - stackblock(); |
out = stackblock(); |
if (eofmark == NULL) { |
if ((c == '>' || c == '<') |
&& quotef == 0 |
&& len <= 2 |
&& (*out == '\0' || is_digit(*out))) { |
PARSEREDIR(); |
return lasttoken = TREDIR; |
} else { |
pungetc(); |
} |
} |
quoteflag = quotef; |
backquotelist = bqlist; |
grabstackblock(len); |
wordtext = out; |
return lasttoken = TWORD; |
/* end of readtoken routine */ |
|
|
|
/* |
* Check to see whether we are at the end of the here document. When this |
* is called, c is set to the first character of the next input line. If |
* we are at the end of the here document, this routine sets the c to PEOF. |
*/ |
|
checkend: { |
if (eofmark) { |
if (striptabs) { |
while (c == '\t') |
c = pgetc(); |
} |
if (c == *eofmark) { |
if (pfgets(line, sizeof line) != NULL) { |
char *p, *q; |
|
p = line; |
for (q = eofmark + 1 ; *q && *p == *q ; p++, q++); |
if (*p == '\n' && *q == '\0') { |
c = PEOF; |
plinno++; |
needprompt = doprompt; |
} else { |
pushstring(line, strlen(line), NULL); |
} |
} |
} |
} |
goto checkend_return; |
} |
|
|
/* |
* Parse a redirection operator. The variable "out" points to a string |
* specifying the fd to be redirected. The variable "c" contains the |
* first character of the redirection operator. |
*/ |
|
parseredir: { |
char fd = *out; |
union node *np; |
|
np = (union node *)stalloc(sizeof (struct nfile)); |
if (c == '>') { |
np->nfile.fd = 1; |
c = pgetc(); |
if (c == '>') |
np->type = NAPPEND; |
else if (c == '&') |
np->type = NTOFD; |
else if (c == '|') |
np->type = NTOOV; |
else { |
np->type = NTO; |
pungetc(); |
} |
} else { /* c == '<' */ |
np->nfile.fd = 0; |
switch (c = pgetc()) { |
case '<': |
if (sizeof (struct nfile) != sizeof (struct nhere)) { |
np = (union node *)stalloc(sizeof (struct nhere)); |
np->nfile.fd = 0; |
} |
np->type = NHERE; |
heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc)); |
heredoc->here = np; |
if ((c = pgetc()) == '-') { |
heredoc->striptabs = 1; |
} else { |
heredoc->striptabs = 0; |
pungetc(); |
} |
break; |
|
case '&': |
np->type = NFROMFD; |
break; |
|
case '>': |
np->type = NFROMTO; |
break; |
|
default: |
np->type = NFROM; |
pungetc(); |
break; |
} |
} |
if (fd != '\0') |
np->nfile.fd = digit_val(fd); |
redirnode = np; |
goto parseredir_return; |
} |
|
|
/* |
* Parse a substitution. At this point, we have read the dollar sign |
* and nothing else. |
*/ |
|
parsesub: { |
int subtype; |
int typeloc; |
int flags; |
char *p; |
static const char types[] = "}-+?="; |
|
c = pgetc(); |
if (c != '(' && c != '{' && !is_name(c) && !is_special(c)) { |
USTPUTC('$', out); |
pungetc(); |
} else if (c == '(') { /* $(command) or $((arith)) */ |
if (pgetc() == '(') { |
PARSEARITH(); |
} else { |
pungetc(); |
PARSEBACKQNEW(); |
} |
} else { |
USTPUTC(CTLVAR, out); |
typeloc = out - stackblock(); |
USTPUTC(VSNORMAL, out); |
subtype = VSNORMAL; |
if (c == '{') { |
c = pgetc(); |
if (c == '#') { |
if ((c = pgetc()) == '}') |
c = '#'; |
else |
subtype = VSLENGTH; |
} |
else |
subtype = 0; |
} |
if (is_name(c)) { |
do { |
STPUTC(c, out); |
c = pgetc(); |
} while (is_in_name(c)); |
} else if (is_digit(c)) { |
do { |
USTPUTC(c, out); |
c = pgetc(); |
} while (is_digit(c)); |
} |
else if (is_special(c)) { |
USTPUTC(c, out); |
c = pgetc(); |
} |
else |
badsub: synerror("Bad substitution"); |
|
STPUTC('=', out); |
flags = 0; |
if (subtype == 0) { |
switch (c) { |
case ':': |
flags = VSNUL; |
c = pgetc(); |
/*FALLTHROUGH*/ |
default: |
p = strchr(types, c); |
if (p == NULL) |
goto badsub; |
subtype = p - types + VSNORMAL; |
break; |
case '%': |
case '#': |
{ |
int cc = c; |
subtype = c == '#' ? VSTRIMLEFT : |
VSTRIMRIGHT; |
c = pgetc(); |
if (c == cc) |
subtype++; |
else |
pungetc(); |
break; |
} |
} |
} else { |
pungetc(); |
} |
if (dblquote || arinest) |
flags |= VSQUOTE; |
*(stackblock() + typeloc) = subtype | flags; |
if (subtype != VSNORMAL) { |
varnest++; |
if (dblquote) { |
dqvarnest++; |
} |
} |
} |
goto parsesub_return; |
} |
|
|
/* |
* Called to parse command substitutions. Newstyle is set if the command |
* is enclosed inside $(...); nlpp is a pointer to the head of the linked |
* list of commands (passed by reference), and savelen is the number of |
* characters on the top of the stack which must be preserved. |
*/ |
|
parsebackq: { |
struct nodelist **nlpp; |
int savepbq; |
union node *n; |
char *volatile str; |
struct jmploc jmploc; |
struct jmploc *volatile savehandler; |
int savelen; |
int saveprompt; |
#ifdef __GNUC__ |
(void) &saveprompt; |
#endif |
|
savepbq = parsebackquote; |
if (setjmp(jmploc.loc)) { |
if (str) |
ckfree(str); |
parsebackquote = 0; |
handler = savehandler; |
longjmp(handler->loc, 1); |
} |
INTOFF; |
str = NULL; |
savelen = out - stackblock(); |
if (savelen > 0) { |
str = ckmalloc(savelen); |
memcpy(str, stackblock(), savelen); |
} |
savehandler = handler; |
handler = &jmploc; |
INTON; |
if (oldstyle) { |
/* We must read until the closing backquote, giving special |
treatment to some slashes, and then push the string and |
reread it as input, interpreting it normally. */ |
char *pout; |
int pc; |
int psavelen; |
char *pstr; |
|
|
STARTSTACKSTR(pout); |
for (;;) { |
if (needprompt) { |
setprompt(2); |
needprompt = 0; |
} |
switch (pc = pgetc()) { |
case '`': |
goto done; |
|
case '\\': |
if ((pc = pgetc()) == '\n') { |
plinno++; |
if (doprompt) |
setprompt(2); |
else |
setprompt(0); |
/* |
* If eating a newline, avoid putting |
* the newline into the new character |
* stream (via the STPUTC after the |
* switch). |
*/ |
continue; |
} |
if (pc != '\\' && pc != '`' && pc != '$' |
&& (!dblquote || pc != '"')) |
STPUTC('\\', pout); |
break; |
|
case '\n': |
plinno++; |
needprompt = doprompt; |
break; |
|
case PEOF: |
startlinno = plinno; |
synerror("EOF in backquote substitution"); |
break; |
|
default: |
break; |
} |
STPUTC(pc, pout); |
} |
done: |
STPUTC('\0', pout); |
psavelen = pout - stackblock(); |
if (psavelen > 0) { |
pstr = grabstackstr(pout); |
setinputstring(pstr, 1); |
} |
} |
nlpp = &bqlist; |
while (*nlpp) |
nlpp = &(*nlpp)->next; |
*nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist)); |
(*nlpp)->next = NULL; |
parsebackquote = oldstyle; |
|
if (oldstyle) { |
saveprompt = doprompt; |
doprompt = 0; |
} |
|
n = list(0); |
|
if (oldstyle) |
doprompt = saveprompt; |
else { |
if (readtoken() != TRP) |
synexpect(TRP); |
} |
|
(*nlpp)->n = n; |
if (oldstyle) { |
/* |
* Start reading from old file again, ignoring any pushed back |
* tokens left from the backquote parsing |
*/ |
popfile(); |
tokpushback = 0; |
} |
while (stackblocksize() <= savelen) |
growstackblock(); |
STARTSTACKSTR(out); |
if (str) { |
memcpy(out, str, savelen); |
STADJUST(savelen, out); |
INTOFF; |
ckfree(str); |
str = NULL; |
INTON; |
} |
parsebackquote = savepbq; |
handler = savehandler; |
if (arinest || dblquote) |
USTPUTC(CTLBACKQ | CTLQUOTE, out); |
else |
USTPUTC(CTLBACKQ, out); |
if (oldstyle) |
goto parsebackq_oldreturn; |
else |
goto parsebackq_newreturn; |
} |
|
/* |
* Parse an arithmetic expansion (indicate start of one and set state) |
*/ |
parsearith: { |
|
if (++arinest == 1) { |
prevsyntax = syntax; |
syntax = ARISYNTAX; |
USTPUTC(CTLARI, out); |
if (dblquote) |
USTPUTC('"',out); |
else |
USTPUTC(' ',out); |
} else { |
/* |
* we collapse embedded arithmetic expansion to |
* parenthesis, which should be equivalent |
*/ |
USTPUTC('(', out); |
} |
goto parsearith_return; |
} |
|
} /* end of readtoken */ |
|
|
|
#ifdef mkinit |
RESET { |
tokpushback = 0; |
checkkwd = 0; |
} |
#endif |
|
/* |
* Returns true if the text contains nothing to expand (no dollar signs |
* or backquotes). |
*/ |
|
STATIC int |
noexpand(text) |
char *text; |
{ |
char *p; |
char c; |
|
p = text; |
while ((c = *p++) != '\0') { |
if (c == CTLQUOTEMARK) |
continue; |
if (c == CTLESC) |
p++; |
else if (BASESYNTAX[(int)c] == CCTL) |
return 0; |
} |
return 1; |
} |
|
|
/* |
* Return true if the argument is a legal variable name (a letter or |
* underscore followed by zero or more letters, underscores, and digits). |
*/ |
|
int |
goodname(char *name) |
{ |
char *p; |
|
p = name; |
if (! is_name(*p)) |
return 0; |
while (*++p) { |
if (! is_in_name(*p)) |
return 0; |
} |
return 1; |
} |
|
|
/* |
* Called when an unexpected token is read during the parse. The argument |
* is the token that is expected, or -1 if more than one type of token can |
* occur at this point. |
*/ |
|
STATIC void |
synexpect(token) |
int token; |
{ |
char msg[64]; |
|
if (token >= 0) { |
fmtstr(msg, 64, "%s unexpected (expecting %s)", |
tokname[lasttoken], tokname[token]); |
} else { |
fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]); |
} |
synerror(msg); |
/* NOTREACHED */ |
} |
|
|
STATIC void |
synerror(msg) |
const char *msg; |
{ |
if (commandname) |
outfmt(&errout, "%s: %d: ", commandname, startlinno); |
outfmt(&errout, "Syntax error: %s\n", msg); |
error((char *)NULL); |
/* NOTREACHED */ |
} |
|
STATIC void |
setprompt(which) |
int which; |
{ |
whichprompt = which; |
|
#ifndef SMALL |
if (!el) |
#endif |
out2str(getprompt(NULL)); |
} |
|
/* |
* called by editline -- any expansions to the prompt |
* should be added here. |
*/ |
const char * |
getprompt(void *unused) |
{ |
switch (whichprompt) { |
case 0: |
return ""; |
case 1: |
return ps1val(); |
case 2: |
return ps2val(); |
default: |
return "<internal prompt error>"; |
} |
} |