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-rw-r--r--bin/sh/parser.c2201
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diff --git a/bin/sh/parser.c b/bin/sh/parser.c
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+/*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 1991, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95";
+#endif
+#endif /* not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <pwd.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include "shell.h"
+#include "parser.h"
+#include "nodes.h"
+#include "expand.h" /* defines rmescapes() */
+#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"
+#include "eval.h"
+#include "exec.h" /* to check for special builtins */
+#ifndef NO_HISTORY
+#include "myhistedit.h"
+#endif
+
+/*
+ * Shell command parser.
+ */
+
+#define PROMPTLEN 128
+
+/* values of checkkwd variable */
+#define CHKALIAS 0x1
+#define CHKKWD 0x2
+#define CHKNL 0x4
+
+/* 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 parser_temp {
+ struct parser_temp *next;
+ void *data;
+};
+
+
+static struct heredoc *heredoclist; /* list of here documents to read */
+static int doprompt; /* if set, prompt the user */
+static int needprompt; /* true if interactive and at start of line */
+static int lasttoken; /* last token read */
+static int tokpushback; /* last token pushed back */
+static char *wordtext; /* text of last word returned by readtoken */
+static int checkkwd;
+static struct nodelist *backquotelist;
+static union node *redirnode;
+static struct heredoc *heredoc;
+static int quoteflag; /* set if (part of) last token was quoted */
+static int startlinno; /* line # where last token started */
+static int funclinno; /* line # where the current function started */
+static struct parser_temp *parser_temp;
+
+#define NOEOFMARK ((const char *)&heredoclist)
+
+
+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 union node *makebinary(int type, union node *n1, union node *n2);
+static void parsefname(void);
+static void parseheredoc(void);
+static int peektoken(void);
+static int readtoken(void);
+static int xxreadtoken(void);
+static int readtoken1(int, const char *, const char *, int);
+static int noexpand(char *);
+static void consumetoken(int);
+static void synexpect(int) __dead2;
+static void synerror(const char *) __dead2;
+static void setprompt(int);
+static int pgetc_linecont(void);
+static void getusername(char *, size_t);
+
+
+static void *
+parser_temp_alloc(size_t len)
+{
+ struct parser_temp *t;
+
+ INTOFF;
+ t = ckmalloc(sizeof(*t));
+ t->data = NULL;
+ t->next = parser_temp;
+ parser_temp = t;
+ t->data = ckmalloc(len);
+ INTON;
+ return t->data;
+}
+
+
+static void *
+parser_temp_realloc(void *ptr, size_t len)
+{
+ struct parser_temp *t;
+
+ INTOFF;
+ t = parser_temp;
+ if (ptr != t->data)
+ error("bug: parser_temp_realloc misused");
+ t->data = ckrealloc(t->data, len);
+ INTON;
+ return t->data;
+}
+
+
+static void
+parser_temp_free_upto(void *ptr)
+{
+ struct parser_temp *t;
+ int done = 0;
+
+ INTOFF;
+ while (parser_temp != NULL && !done) {
+ t = parser_temp;
+ parser_temp = t->next;
+ done = t->data == ptr;
+ ckfree(t->data);
+ ckfree(t);
+ }
+ INTON;
+ if (!done)
+ error("bug: parser_temp_free_upto misused");
+}
+
+
+static void
+parser_temp_free_all(void)
+{
+ struct parser_temp *t;
+
+ INTOFF;
+ while (parser_temp != NULL) {
+ t = parser_temp;
+ parser_temp = t->next;
+ ckfree(t->data);
+ ckfree(t);
+ }
+ INTON;
+}
+
+
+/*
+ * 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;
+
+ /* This assumes the parser is not re-entered,
+ * which could happen if we add command substitution on PS1/PS2.
+ */
+ parser_temp_free_all();
+ heredoclist = NULL;
+
+ tokpushback = 0;
+ checkkwd = 0;
+ 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);
+}
+
+
+/*
+ * Read and parse words for wordexp.
+ * Returns a list of NARG nodes; NULL if there are no words.
+ */
+union node *
+parsewordexp(void)
+{
+ union node *n, *first = NULL, **pnext;
+ int t;
+
+ /* This assumes the parser is not re-entered,
+ * which could happen if we add command substitution on PS1/PS2.
+ */
+ parser_temp_free_all();
+ heredoclist = NULL;
+
+ tokpushback = 0;
+ checkkwd = 0;
+ doprompt = 0;
+ setprompt(0);
+ needprompt = 0;
+ pnext = &first;
+ while ((t = readtoken()) != TEOF) {
+ if (t != TWORD)
+ synexpect(TWORD);
+ n = makename();
+ *pnext = n;
+ pnext = &n->narg.next;
+ }
+ return first;
+}
+
+
+static union node *
+list(int nlflag)
+{
+ union node *ntop, *n1, *n2, *n3;
+ int tok;
+
+ checkkwd = CHKNL | CHKKWD | CHKALIAS;
+ if (!nlflag && tokendlist[peektoken()])
+ return NULL;
+ ntop = n1 = NULL;
+ for (;;) {
+ n2 = andor();
+ tok = readtoken();
+ if (tok == TBACKGND) {
+ if (n2 != NULL && n2->type == NPIPE) {
+ n2->npipe.backgnd = 1;
+ } else if (n2 != NULL && 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 (ntop == NULL)
+ ntop = n2;
+ else if (n1 == NULL) {
+ n1 = makebinary(NSEMI, ntop, n2);
+ ntop = n1;
+ }
+ else {
+ n3 = makebinary(NSEMI, n1->nbinary.ch2, n2);
+ n1->nbinary.ch2 = n3;
+ n1 = n3;
+ }
+ switch (tok) {
+ case TBACKGND:
+ case TSEMI:
+ tok = readtoken();
+ /* FALLTHROUGH */
+ case TNL:
+ if (tok == TNL) {
+ parseheredoc();
+ if (nlflag)
+ return ntop;
+ } else if (tok == TEOF && nlflag) {
+ parseheredoc();
+ return ntop;
+ } else {
+ tokpushback++;
+ }
+ checkkwd = CHKNL | CHKKWD | CHKALIAS;
+ if (!nlflag && tokendlist[peektoken()])
+ return ntop;
+ break;
+ case TEOF:
+ if (heredoclist)
+ parseheredoc();
+ else
+ pungetc(); /* push back EOF on input */
+ return ntop;
+ default:
+ if (nlflag)
+ synexpect(-1);
+ tokpushback++;
+ return ntop;
+ }
+ }
+}
+
+
+
+static union node *
+andor(void)
+{
+ union node *n;
+ int t;
+
+ n = pipeline();
+ for (;;) {
+ if ((t = readtoken()) == TAND) {
+ t = NAND;
+ } else if (t == TOR) {
+ t = NOR;
+ } else {
+ tokpushback++;
+ return n;
+ }
+ n = makebinary(t, n, pipeline());
+ }
+}
+
+
+
+static union node *
+pipeline(void)
+{
+ union node *n1, *n2, *pipenode;
+ struct nodelist *lp, *prev;
+ int negate, t;
+
+ negate = 0;
+ checkkwd = CHKNL | CHKKWD | CHKALIAS;
+ TRACE(("pipeline: entered\n"));
+ while (readtoken() == TNOT)
+ negate = !negate;
+ 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 = CHKNL | CHKKWD | CHKALIAS;
+ t = readtoken();
+ tokpushback++;
+ if (t == TNOT)
+ lp->n = pipeline();
+ else
+ 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(void)
+{
+ union node *n1, *n2;
+ union node *ap, **app;
+ union node *cp, **cpp;
+ union node *redir, **rpp;
+ int t;
+ int is_subshell;
+
+ checkkwd = CHKNL | CHKKWD | CHKALIAS;
+ is_subshell = 0;
+ 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;
+ if ((n1->nif.test = list(0)) == NULL)
+ synexpect(-1);
+ consumetoken(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;
+ if ((n2->nif.test = list(0)) == NULL)
+ synexpect(-1);
+ consumetoken(TTHEN);
+ n2->nif.ifpart = list(0);
+ }
+ if (lasttoken == TELSE)
+ n2->nif.elsepart = list(0);
+ else {
+ n2->nif.elsepart = NULL;
+ tokpushback++;
+ }
+ consumetoken(TFI);
+ checkkwd = CHKKWD | CHKALIAS;
+ break;
+ case TWHILE:
+ case TUNTIL:
+ t = lasttoken;
+ if ((n1 = list(0)) == NULL)
+ synexpect(-1);
+ consumetoken(TDO);
+ n1 = makebinary((t == TWHILE)? NWHILE : NUNTIL, n1, list(0));
+ consumetoken(TDONE);
+ checkkwd = CHKKWD | CHKALIAS;
+ 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;
+ while (readtoken() == TNL)
+ ;
+ if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) {
+ app = &ap;
+ while (readtoken() == TWORD) {
+ n2 = makename();
+ *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 = CHKNL | CHKKWD | CHKALIAS;
+ if ((t = readtoken()) == TDO)
+ t = TDONE;
+ else if (t == TBEGIN)
+ t = TEND;
+ else
+ synexpect(-1);
+ n1->nfor.body = list(0);
+ consumetoken(t);
+ checkkwd = CHKKWD | CHKALIAS;
+ break;
+ case TCASE:
+ n1 = (union node *)stalloc(sizeof (struct ncase));
+ n1->type = NCASE;
+ consumetoken(TWORD);
+ n1->ncase.expr = makename();
+ while (readtoken() == TNL);
+ if (lasttoken != TWORD || ! equal(wordtext, "in"))
+ synerror("expecting \"in\"");
+ cpp = &n1->ncase.cases;
+ checkkwd = CHKNL | CHKKWD, readtoken();
+ while (lasttoken != TESAC) {
+ *cpp = cp = (union node *)stalloc(sizeof (struct nclist));
+ cp->type = NCLIST;
+ app = &cp->nclist.pattern;
+ if (lasttoken == TLP)
+ readtoken();
+ for (;;) {
+ *app = ap = makename();
+ checkkwd = CHKNL | CHKKWD;
+ if (readtoken() != TPIPE)
+ break;
+ app = &ap->narg.next;
+ readtoken();
+ }
+ ap->narg.next = NULL;
+ if (lasttoken != TRP)
+ synexpect(TRP);
+ cp->nclist.body = list(0);
+
+ checkkwd = CHKNL | CHKKWD | CHKALIAS;
+ if ((t = readtoken()) != TESAC) {
+ if (t == TENDCASE)
+ ;
+ else if (t == TFALLTHRU)
+ cp->type = NCLISTFALLTHRU;
+ else
+ synexpect(TENDCASE);
+ checkkwd = CHKNL | CHKKWD, readtoken();
+ }
+ cpp = &cp->nclist.next;
+ }
+ *cpp = NULL;
+ checkkwd = CHKKWD | CHKALIAS;
+ break;
+ case TLP:
+ n1 = (union node *)stalloc(sizeof (struct nredir));
+ n1->type = NSUBSHELL;
+ n1->nredir.n = list(0);
+ n1->nredir.redirect = NULL;
+ consumetoken(TRP);
+ checkkwd = CHKKWD | CHKALIAS;
+ is_subshell = 1;
+ break;
+ case TBEGIN:
+ n1 = list(0);
+ consumetoken(TEND);
+ checkkwd = CHKKWD | CHKALIAS;
+ break;
+ /* A simple command must have at least one redirection or word. */
+ case TBACKGND:
+ case TSEMI:
+ case TAND:
+ case TOR:
+ case TPIPE:
+ case TENDCASE:
+ case TFALLTHRU:
+ case TEOF:
+ case TNL:
+ case TRP:
+ if (!redir)
+ synexpect(-1);
+ case TWORD:
+ tokpushback++;
+ n1 = simplecmd(rpp, redir);
+ return n1;
+ default:
+ synexpect(-1);
+ }
+
+ /* 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 (!is_subshell) {
+ 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(union node **rpp, union node *redir)
+{
+ union node *args, **app;
+ union node **orig_rpp = rpp;
+ union node *n = NULL;
+ int special;
+ int savecheckkwd;
+
+ /* If we don't have any redirections already, then we must reset */
+ /* rpp to be the address of the local redir variable. */
+ if (redir == NULL)
+ 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;
+
+ savecheckkwd = CHKALIAS;
+
+ for (;;) {
+ checkkwd = savecheckkwd;
+ if (readtoken() == TWORD) {
+ n = makename();
+ *app = n;
+ app = &n->narg.next;
+ if (savecheckkwd != 0 && !isassignment(wordtext))
+ savecheckkwd = 0;
+ } 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 */
+ consumetoken(TRP);
+ funclinno = plinno;
+ /*
+ * - Require plain text.
+ * - Functions with '/' cannot be called.
+ * - Reject name=().
+ * - Reject ksh extended glob patterns.
+ */
+ if (!noexpand(n->narg.text) || quoteflag ||
+ strchr(n->narg.text, '/') ||
+ strchr("!%*+-=?@}~",
+ n->narg.text[strlen(n->narg.text) - 1]))
+ synerror("Bad function name");
+ rmescapes(n->narg.text);
+ if (find_builtin(n->narg.text, &special) >= 0 &&
+ special)
+ synerror("Cannot override a special builtin with a function");
+ n->type = NDEFUN;
+ n->narg.next = command();
+ funclinno = 0;
+ return n;
+ } else {
+ tokpushback++;
+ break;
+ }
+ }
+ *app = NULL;
+ *rpp = NULL;
+ n = (union node *)stalloc(sizeof (struct ncmd));
+ n->type = NCMD;
+ n->ncmd.args = args;
+ n->ncmd.redirect = redir;
+ return n;
+}
+
+static union node *
+makename(void)
+{
+ 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;
+}
+
+static union node *
+makebinary(int type, union node *n1, union node *n2)
+{
+ union node *n;
+
+ n = (union node *)stalloc(sizeof (struct nbinary));
+ n->type = type;
+ n->nbinary.ch1 = n1;
+ n->nbinary.ch2 = n2;
+ return (n);
+}
+
+void
+forcealias(void)
+{
+ checkkwd |= CHKALIAS;
+}
+
+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(void)
+{
+ union node *n = redirnode;
+
+ consumetoken(TWORD);
+ if (n->type == NHERE) {
+ struct heredoc *here = heredoc;
+ struct heredoc *p;
+
+ if (quoteflag == 0)
+ n->type = NXHERE;
+ TRACE(("Here document %d\n", n->type));
+ if (here->striptabs) {
+ while (*wordtext == '\t')
+ wordtext++;
+ }
+ if (! noexpand(wordtext))
+ 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(void)
+{
+ 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 = makename();
+ here->here->nhere.doc = n;
+ }
+}
+
+static int
+peektoken(void)
+{
+ int t;
+
+ t = readtoken();
+ tokpushback++;
+ return (t);
+}
+
+static int
+readtoken(void)
+{
+ int t;
+ struct alias *ap;
+#ifdef DEBUG
+ int alreadyseen = tokpushback;
+#endif
+
+ top:
+ t = xxreadtoken();
+
+ /*
+ * eat newlines
+ */
+ if (checkkwd & CHKNL) {
+ while (t == TNL) {
+ parseheredoc();
+ t = xxreadtoken();
+ }
+ }
+
+ /*
+ * check for keywords and aliases
+ */
+ if (t == TWORD && !quoteflag)
+ {
+ const char * const *pp;
+
+ if (checkkwd & CHKKWD)
+ 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 (checkkwd & CHKALIAS &&
+ (ap = lookupalias(wordtext, 1)) != NULL) {
+ pushstring(ap->val, strlen(ap->val), ap);
+ goto top;
+ }
+ }
+out:
+ if (t != TNOT)
+ 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(void)
+{
+ 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();
+ 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();
+ /* FALLTHROUGH */
+ default:
+ return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
+ case '\n':
+ plinno++;
+ needprompt = doprompt;
+ RETURN(TNL);
+ case PEOF:
+ RETURN(TEOF);
+ case '&':
+ if (pgetc_linecont() == '&')
+ RETURN(TAND);
+ pungetc();
+ RETURN(TBACKGND);
+ case '|':
+ if (pgetc_linecont() == '|')
+ RETURN(TOR);
+ pungetc();
+ RETURN(TPIPE);
+ case ';':
+ c = pgetc_linecont();
+ if (c == ';')
+ RETURN(TENDCASE);
+ else if (c == '&')
+ RETURN(TFALLTHRU);
+ pungetc();
+ RETURN(TSEMI);
+ case '(':
+ RETURN(TLP);
+ case ')':
+ RETURN(TRP);
+ }
+ }
+#undef RETURN
+}
+
+
+#define MAXNEST_static 8
+struct tokenstate
+{
+ const char *syntax; /* *SYNTAX */
+ int parenlevel; /* levels of parentheses in arithmetic */
+ enum tokenstate_category
+ {
+ TSTATE_TOP,
+ TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */
+ TSTATE_VAR_NEW, /* other ${var...}, own dquote state */
+ TSTATE_ARITH
+ } category;
+};
+
+
+/*
+ * 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.
+ * The new value of c is returned.
+ */
+
+static int
+checkend(int c, const char *eofmark, int striptabs)
+{
+ if (striptabs) {
+ while (c == '\t')
+ c = pgetc();
+ }
+ if (c == *eofmark) {
+ int c2;
+ const char *q;
+
+ for (q = eofmark + 1; c2 = pgetc(), *q != '\0' && c2 == *q; q++)
+ ;
+ if ((c2 == PEOF || c2 == '\n') && *q == '\0') {
+ c = PEOF;
+ if (c2 == '\n') {
+ plinno++;
+ needprompt = doprompt;
+ }
+ } else {
+ pungetc();
+ pushstring(eofmark + 1, q - (eofmark + 1), NULL);
+ }
+ } else if (c == '\n' && *eofmark == '\0') {
+ c = PEOF;
+ plinno++;
+ needprompt = doprompt;
+ }
+ return (c);
+}
+
+
+/*
+ * 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.
+ */
+
+static void
+parseredir(char *out, int c)
+{
+ char fd = *out;
+ union node *np;
+
+ np = (union node *)stalloc(sizeof (struct nfile));
+ if (c == '>') {
+ np->nfile.fd = 1;
+ c = pgetc_linecont();
+ if (c == '>')
+ np->type = NAPPEND;
+ else if (c == '&')
+ np->type = NTOFD;
+ else if (c == '|')
+ np->type = NCLOBBER;
+ else {
+ np->type = NTO;
+ pungetc();
+ }
+ } else { /* c == '<' */
+ np->nfile.fd = 0;
+ c = pgetc_linecont();
+ if (c == '<') {
+ 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_linecont()) == '-') {
+ heredoc->striptabs = 1;
+ } else {
+ heredoc->striptabs = 0;
+ pungetc();
+ }
+ } else if (c == '&')
+ np->type = NFROMFD;
+ else if (c == '>')
+ np->type = NFROMTO;
+ else {
+ np->type = NFROM;
+ pungetc();
+ }
+ }
+ if (fd != '\0')
+ np->nfile.fd = digit_val(fd);
+ redirnode = np;
+}
+
+/*
+ * Called to parse command substitutions.
+ */
+
+static char *
+parsebackq(char *out, struct nodelist **pbqlist,
+ int oldstyle, int dblquote, int quoted)
+{
+ struct nodelist **nlpp;
+ union node *n;
+ char *volatile str;
+ struct jmploc jmploc;
+ struct jmploc *const savehandler = handler;
+ size_t savelen;
+ int saveprompt;
+ const int bq_startlinno = plinno;
+ char *volatile ostr = NULL;
+ struct parsefile *const savetopfile = getcurrentfile();
+ struct heredoc *const saveheredoclist = heredoclist;
+ struct heredoc *here;
+
+ str = NULL;
+ if (setjmp(jmploc.loc)) {
+ popfilesupto(savetopfile);
+ if (str)
+ ckfree(str);
+ if (ostr)
+ ckfree(ostr);
+ heredoclist = saveheredoclist;
+ handler = savehandler;
+ if (exception == EXERROR) {
+ startlinno = bq_startlinno;
+ synerror("Error in command substitution");
+ }
+ longjmp(handler->loc, 1);
+ }
+ INTOFF;
+ savelen = out - stackblock();
+ if (savelen > 0) {
+ str = ckmalloc(savelen);
+ memcpy(str, stackblock(), savelen);
+ }
+ handler = &jmploc;
+ heredoclist = NULL;
+ 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 *oout;
+ int c;
+ int olen;
+
+
+ STARTSTACKSTR(oout);
+ for (;;) {
+ if (needprompt) {
+ setprompt(2);
+ needprompt = 0;
+ }
+ CHECKSTRSPACE(2, oout);
+ c = pgetc_linecont();
+ if (c == '`')
+ break;
+ switch (c) {
+ case '\\':
+ c = pgetc();
+ if (c != '\\' && c != '`' && c != '$'
+ && (!dblquote || c != '"'))
+ USTPUTC('\\', oout);
+ break;
+
+ case '\n':
+ plinno++;
+ needprompt = doprompt;
+ break;
+
+ case PEOF:
+ startlinno = plinno;
+ synerror("EOF in backquote substitution");
+ break;
+
+ default:
+ break;
+ }
+ USTPUTC(c, oout);
+ }
+ USTPUTC('\0', oout);
+ olen = oout - stackblock();
+ INTOFF;
+ ostr = ckmalloc(olen);
+ memcpy(ostr, stackblock(), olen);
+ setinputstring(ostr, 1);
+ INTON;
+ }
+ nlpp = pbqlist;
+ while (*nlpp)
+ nlpp = &(*nlpp)->next;
+ *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist));
+ (*nlpp)->next = NULL;
+
+ if (oldstyle) {
+ saveprompt = doprompt;
+ doprompt = 0;
+ }
+
+ n = list(0);
+
+ if (oldstyle) {
+ if (peektoken() != TEOF)
+ synexpect(-1);
+ doprompt = saveprompt;
+ } else
+ consumetoken(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;
+ }
+ STARTSTACKSTR(out);
+ CHECKSTRSPACE(savelen + 1, out);
+ INTOFF;
+ if (str) {
+ memcpy(out, str, savelen);
+ STADJUST(savelen, out);
+ ckfree(str);
+ str = NULL;
+ }
+ if (ostr) {
+ ckfree(ostr);
+ ostr = NULL;
+ }
+ here = saveheredoclist;
+ if (here != NULL) {
+ while (here->next != NULL)
+ here = here->next;
+ here->next = heredoclist;
+ heredoclist = saveheredoclist;
+ }
+ handler = savehandler;
+ INTON;
+ if (quoted)
+ USTPUTC(CTLBACKQ | CTLQUOTE, out);
+ else
+ USTPUTC(CTLBACKQ, out);
+ return out;
+}
+
+
+/*
+ * Called to parse a backslash escape sequence inside $'...'.
+ * The backslash has already been read.
+ */
+static char *
+readcstyleesc(char *out)
+{
+ int c, vc, i, n;
+ unsigned int v;
+
+ c = pgetc();
+ switch (c) {
+ case '\0':
+ synerror("Unterminated quoted string");
+ case '\n':
+ plinno++;
+ if (doprompt)
+ setprompt(2);
+ else
+ setprompt(0);
+ return out;
+ case '\\':
+ case '\'':
+ case '"':
+ v = c;
+ break;
+ case 'a': v = '\a'; break;
+ case 'b': v = '\b'; break;
+ case 'e': v = '\033'; break;
+ case 'f': v = '\f'; break;
+ case 'n': v = '\n'; break;
+ case 'r': v = '\r'; break;
+ case 't': v = '\t'; break;
+ case 'v': v = '\v'; break;
+ case 'x':
+ v = 0;
+ for (;;) {
+ c = pgetc();
+ if (c >= '0' && c <= '9')
+ v = (v << 4) + c - '0';
+ else if (c >= 'A' && c <= 'F')
+ v = (v << 4) + c - 'A' + 10;
+ else if (c >= 'a' && c <= 'f')
+ v = (v << 4) + c - 'a' + 10;
+ else
+ break;
+ }
+ pungetc();
+ break;
+ case '0': case '1': case '2': case '3':
+ case '4': case '5': case '6': case '7':
+ v = c - '0';
+ c = pgetc();
+ if (c >= '0' && c <= '7') {
+ v <<= 3;
+ v += c - '0';
+ c = pgetc();
+ if (c >= '0' && c <= '7') {
+ v <<= 3;
+ v += c - '0';
+ } else
+ pungetc();
+ } else
+ pungetc();
+ break;
+ case 'c':
+ c = pgetc();
+ if (c < 0x3f || c > 0x7a || c == 0x60)
+ synerror("Bad escape sequence");
+ if (c == '\\' && pgetc() != '\\')
+ synerror("Bad escape sequence");
+ if (c == '?')
+ v = 127;
+ else
+ v = c & 0x1f;
+ break;
+ case 'u':
+ case 'U':
+ n = c == 'U' ? 8 : 4;
+ v = 0;
+ for (i = 0; i < n; i++) {
+ c = pgetc();
+ if (c >= '0' && c <= '9')
+ v = (v << 4) + c - '0';
+ else if (c >= 'A' && c <= 'F')
+ v = (v << 4) + c - 'A' + 10;
+ else if (c >= 'a' && c <= 'f')
+ v = (v << 4) + c - 'a' + 10;
+ else
+ synerror("Bad escape sequence");
+ }
+ if (v == 0 || (v >= 0xd800 && v <= 0xdfff))
+ synerror("Bad escape sequence");
+ /* We really need iconv here. */
+ if (initial_localeisutf8 && v > 127) {
+ CHECKSTRSPACE(4, out);
+ /*
+ * We cannot use wctomb() as the locale may have
+ * changed.
+ */
+ if (v <= 0x7ff) {
+ USTPUTC(0xc0 | v >> 6, out);
+ USTPUTC(0x80 | (v & 0x3f), out);
+ return out;
+ } else if (v <= 0xffff) {
+ USTPUTC(0xe0 | v >> 12, out);
+ USTPUTC(0x80 | ((v >> 6) & 0x3f), out);
+ USTPUTC(0x80 | (v & 0x3f), out);
+ return out;
+ } else if (v <= 0x10ffff) {
+ USTPUTC(0xf0 | v >> 18, out);
+ USTPUTC(0x80 | ((v >> 12) & 0x3f), out);
+ USTPUTC(0x80 | ((v >> 6) & 0x3f), out);
+ USTPUTC(0x80 | (v & 0x3f), out);
+ return out;
+ }
+ }
+ if (v > 127)
+ v = '?';
+ break;
+ default:
+ synerror("Bad escape sequence");
+ }
+ vc = (char)v;
+ /*
+ * We can't handle NUL bytes.
+ * POSIX says we should skip till the closing quote.
+ */
+ if (vc == '\0') {
+ while ((c = pgetc()) != '\'') {
+ if (c == '\\')
+ c = pgetc();
+ if (c == PEOF)
+ synerror("Unterminated quoted string");
+ if (c == '\n') {
+ plinno++;
+ if (doprompt)
+ setprompt(2);
+ else
+ setprompt(0);
+ }
+ }
+ pungetc();
+ return out;
+ }
+ if (SQSYNTAX[vc] == CCTL)
+ USTPUTC(CTLESC, out);
+ USTPUTC(vc, out);
+ return out;
+}
+
+
+/*
+ * 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 PARSESUB() {goto parsesub; parsesub_return:;}
+#define PARSEARITH() {goto parsearith; parsearith_return:;}
+
+static int
+readtoken1(int firstc, char const *initialsyntax, const char *eofmark,
+ int striptabs)
+{
+ int c = firstc;
+ char *out;
+ int len;
+ struct nodelist *bqlist;
+ int quotef;
+ int newvarnest;
+ int level;
+ int synentry;
+ struct tokenstate state_static[MAXNEST_static];
+ int maxnest = MAXNEST_static;
+ struct tokenstate *state = state_static;
+ int sqiscstyle = 0;
+
+ startlinno = plinno;
+ quotef = 0;
+ bqlist = NULL;
+ newvarnest = 0;
+ level = 0;
+ state[level].syntax = initialsyntax;
+ state[level].parenlevel = 0;
+ state[level].category = TSTATE_TOP;
+
+ STARTSTACKSTR(out);
+ loop: { /* for each line, until end of word */
+ if (eofmark && eofmark != NOEOFMARK)
+ /* set c to PEOF if at end of here document */
+ c = checkend(c, eofmark, striptabs);
+ for (;;) { /* until end of line or end of word */
+ CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */
+
+ synentry = state[level].syntax[c];
+
+ switch(synentry) {
+ case CNL: /* '\n' */
+ if (level == 0)
+ goto endword; /* exit outer loop */
+ /* FALLTHROUGH */
+ case CQNL:
+ USTPUTC(c, out);
+ plinno++;
+ if (doprompt)
+ setprompt(2);
+ else
+ setprompt(0);
+ c = pgetc();
+ goto loop; /* continue outer loop */
+ case CSBACK:
+ if (sqiscstyle) {
+ out = readcstyleesc(out);
+ break;
+ }
+ /* FALLTHROUGH */
+ case CWORD:
+ USTPUTC(c, out);
+ break;
+ case CCTL:
+ if (eofmark == NULL || initialsyntax != SQSYNTAX)
+ USTPUTC(CTLESC, out);
+ USTPUTC(c, out);
+ break;
+ case CBACK: /* backslash */
+ c = pgetc();
+ if (c == PEOF) {
+ USTPUTC('\\', out);
+ pungetc();
+ } else if (c == '\n') {
+ plinno++;
+ if (doprompt)
+ setprompt(2);
+ else
+ setprompt(0);
+ } else {
+ if (state[level].syntax == DQSYNTAX &&
+ c != '\\' && c != '`' && c != '$' &&
+ (c != '"' || (eofmark != NULL &&
+ newvarnest == 0)) &&
+ (c != '}' || state[level].category != TSTATE_VAR_OLD))
+ USTPUTC('\\', out);
+ if ((eofmark == NULL ||
+ newvarnest > 0) &&
+ state[level].syntax == BASESYNTAX)
+ USTPUTC(CTLQUOTEMARK, out);
+ if (SQSYNTAX[c] == CCTL)
+ USTPUTC(CTLESC, out);
+ USTPUTC(c, out);
+ if ((eofmark == NULL ||
+ newvarnest > 0) &&
+ state[level].syntax == BASESYNTAX &&
+ state[level].category == TSTATE_VAR_OLD)
+ USTPUTC(CTLQUOTEEND, out);
+ quotef++;
+ }
+ break;
+ case CSQUOTE:
+ USTPUTC(CTLQUOTEMARK, out);
+ state[level].syntax = SQSYNTAX;
+ sqiscstyle = 0;
+ break;
+ case CDQUOTE:
+ USTPUTC(CTLQUOTEMARK, out);
+ state[level].syntax = DQSYNTAX;
+ break;
+ case CENDQUOTE:
+ if (eofmark != NULL && newvarnest == 0)
+ USTPUTC(c, out);
+ else {
+ if (state[level].category == TSTATE_VAR_OLD)
+ USTPUTC(CTLQUOTEEND, out);
+ state[level].syntax = BASESYNTAX;
+ quotef++;
+ }
+ break;
+ case CVAR: /* '$' */
+ PARSESUB(); /* parse substitution */
+ break;
+ case CENDVAR: /* '}' */
+ if (level > 0 &&
+ ((state[level].category == TSTATE_VAR_OLD &&
+ state[level].syntax ==
+ state[level - 1].syntax) ||
+ (state[level].category == TSTATE_VAR_NEW &&
+ state[level].syntax == BASESYNTAX))) {
+ if (state[level].category == TSTATE_VAR_NEW)
+ newvarnest--;
+ level--;
+ USTPUTC(CTLENDVAR, out);
+ } else {
+ USTPUTC(c, out);
+ }
+ break;
+ case CLP: /* '(' in arithmetic */
+ state[level].parenlevel++;
+ USTPUTC(c, out);
+ break;
+ case CRP: /* ')' in arithmetic */
+ if (state[level].parenlevel > 0) {
+ USTPUTC(c, out);
+ --state[level].parenlevel;
+ } else {
+ if (pgetc_linecont() == ')') {
+ if (level > 0 &&
+ state[level].category == TSTATE_ARITH) {
+ level--;
+ USTPUTC(CTLENDARI, out);
+ } else
+ USTPUTC(')', out);
+ } else {
+ /*
+ * unbalanced parens
+ * (don't 2nd guess - no error)
+ */
+ pungetc();
+ USTPUTC(')', out);
+ }
+ }
+ break;
+ case CBQUOTE: /* '`' */
+ out = parsebackq(out, &bqlist, 1,
+ state[level].syntax == DQSYNTAX &&
+ (eofmark == NULL || newvarnest > 0),
+ state[level].syntax == DQSYNTAX || state[level].syntax == ARISYNTAX);
+ break;
+ case CEOF:
+ goto endword; /* exit outer loop */
+ case CIGN:
+ break;
+ default:
+ if (level == 0)
+ goto endword; /* exit outer loop */
+ USTPUTC(c, out);
+ }
+ c = pgetc_macro();
+ }
+ }
+endword:
+ if (state[level].syntax == ARISYNTAX)
+ synerror("Missing '))'");
+ if (state[level].syntax != BASESYNTAX && eofmark == NULL)
+ synerror("Unterminated quoted string");
+ if (state[level].category == TSTATE_VAR_OLD ||
+ state[level].category == TSTATE_VAR_NEW) {
+ startlinno = plinno;
+ synerror("Missing '}'");
+ }
+ if (state != state_static)
+ parser_temp_free_upto(state);
+ USTPUTC('\0', out);
+ len = out - stackblock();
+ out = stackblock();
+ if (eofmark == NULL) {
+ if ((c == '>' || c == '<')
+ && quotef == 0
+ && len <= 2
+ && (*out == '\0' || is_digit(*out))) {
+ parseredir(out, c);
+ return lasttoken = TREDIR;
+ } else {
+ pungetc();
+ }
+ }
+ quoteflag = quotef;
+ backquotelist = bqlist;
+ grabstackblock(len);
+ wordtext = out;
+ return lasttoken = TWORD;
+/* end of readtoken routine */
+
+
+/*
+ * 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[] = "}-+?=";
+ int linno;
+ int length;
+ int c1;
+
+ c = pgetc_linecont();
+ if (c == '(') { /* $(command) or $((arith)) */
+ if (pgetc_linecont() == '(') {
+ PARSEARITH();
+ } else {
+ pungetc();
+ out = parsebackq(out, &bqlist, 0,
+ state[level].syntax == DQSYNTAX &&
+ (eofmark == NULL || newvarnest > 0),
+ state[level].syntax == DQSYNTAX ||
+ state[level].syntax == ARISYNTAX);
+ }
+ } else if (c == '{' || is_name(c) || is_special(c)) {
+ USTPUTC(CTLVAR, out);
+ typeloc = out - stackblock();
+ USTPUTC(VSNORMAL, out);
+ subtype = VSNORMAL;
+ flags = 0;
+ if (c == '{') {
+ c = pgetc_linecont();
+ subtype = 0;
+ }
+varname:
+ if (!is_eof(c) && is_name(c)) {
+ length = 0;
+ do {
+ STPUTC(c, out);
+ c = pgetc_linecont();
+ length++;
+ } while (!is_eof(c) && is_in_name(c));
+ if (length == 6 &&
+ strncmp(out - length, "LINENO", length) == 0) {
+ /* Replace the variable name with the
+ * current line number. */
+ STADJUST(-6, out);
+ CHECKSTRSPACE(11, out);
+ linno = plinno;
+ if (funclinno != 0)
+ linno -= funclinno - 1;
+ length = snprintf(out, 11, "%d", linno);
+ if (length > 10)
+ length = 10;
+ out += length;
+ flags |= VSLINENO;
+ }
+ } else if (is_digit(c)) {
+ if (subtype != VSNORMAL) {
+ do {
+ STPUTC(c, out);
+ c = pgetc_linecont();
+ } while (is_digit(c));
+ } else {
+ USTPUTC(c, out);
+ c = pgetc_linecont();
+ }
+ } else if (is_special(c)) {
+ c1 = c;
+ c = pgetc_linecont();
+ if (subtype == 0 && c1 == '#') {
+ subtype = VSLENGTH;
+ if (strchr(types, c) == NULL && c != ':' &&
+ c != '#' && c != '%')
+ goto varname;
+ c1 = c;
+ c = pgetc_linecont();
+ if (c1 != '}' && c == '}') {
+ pungetc();
+ c = c1;
+ goto varname;
+ }
+ pungetc();
+ c = c1;
+ c1 = '#';
+ subtype = 0;
+ }
+ USTPUTC(c1, out);
+ } else {
+ subtype = VSERROR;
+ if (c == '}')
+ pungetc();
+ else if (c == '\n' || c == PEOF)
+ synerror("Unexpected end of line in substitution");
+ else if (BASESYNTAX[c] != CCTL)
+ USTPUTC(c, out);
+ }
+ if (subtype == 0) {
+ switch (c) {
+ case ':':
+ flags |= VSNUL;
+ c = pgetc_linecont();
+ /*FALLTHROUGH*/
+ default:
+ p = strchr(types, c);
+ if (p == NULL) {
+ if (c == '\n' || c == PEOF)
+ synerror("Unexpected end of line in substitution");
+ if (flags == VSNUL)
+ STPUTC(':', out);
+ if (BASESYNTAX[c] != CCTL)
+ STPUTC(c, out);
+ subtype = VSERROR;
+ } else
+ subtype = p - types + VSNORMAL;
+ break;
+ case '%':
+ case '#':
+ {
+ int cc = c;
+ subtype = c == '#' ? VSTRIMLEFT :
+ VSTRIMRIGHT;
+ c = pgetc_linecont();
+ if (c == cc)
+ subtype++;
+ else
+ pungetc();
+ break;
+ }
+ }
+ } else if (subtype != VSERROR) {
+ if (subtype == VSLENGTH && c != '}')
+ subtype = VSERROR;
+ pungetc();
+ }
+ STPUTC('=', out);
+ if (state[level].syntax == DQSYNTAX ||
+ state[level].syntax == ARISYNTAX)
+ flags |= VSQUOTE;
+ *(stackblock() + typeloc) = subtype | flags;
+ if (subtype != VSNORMAL) {
+ if (level + 1 >= maxnest) {
+ maxnest *= 2;
+ if (state == state_static) {
+ state = parser_temp_alloc(
+ maxnest * sizeof(*state));
+ memcpy(state, state_static,
+ MAXNEST_static * sizeof(*state));
+ } else
+ state = parser_temp_realloc(state,
+ maxnest * sizeof(*state));
+ }
+ level++;
+ state[level].parenlevel = 0;
+ if (subtype == VSMINUS || subtype == VSPLUS ||
+ subtype == VSQUESTION || subtype == VSASSIGN) {
+ /*
+ * For operators that were in the Bourne shell,
+ * inherit the double-quote state.
+ */
+ state[level].syntax = state[level - 1].syntax;
+ state[level].category = TSTATE_VAR_OLD;
+ } else {
+ /*
+ * The other operators take a pattern,
+ * so go to BASESYNTAX.
+ * Also, ' and " are now special, even
+ * in here documents.
+ */
+ state[level].syntax = BASESYNTAX;
+ state[level].category = TSTATE_VAR_NEW;
+ newvarnest++;
+ }
+ }
+ } else if (c == '\'' && state[level].syntax == BASESYNTAX) {
+ /* $'cstylequotes' */
+ USTPUTC(CTLQUOTEMARK, out);
+ state[level].syntax = SQSYNTAX;
+ sqiscstyle = 1;
+ } else {
+ USTPUTC('$', out);
+ pungetc();
+ }
+ goto parsesub_return;
+}
+
+
+/*
+ * Parse an arithmetic expansion (indicate start of one and set state)
+ */
+parsearith: {
+
+ if (level + 1 >= maxnest) {
+ maxnest *= 2;
+ if (state == state_static) {
+ state = parser_temp_alloc(
+ maxnest * sizeof(*state));
+ memcpy(state, state_static,
+ MAXNEST_static * sizeof(*state));
+ } else
+ state = parser_temp_realloc(state,
+ maxnest * sizeof(*state));
+ }
+ level++;
+ state[level].syntax = ARISYNTAX;
+ state[level].parenlevel = 0;
+ state[level].category = TSTATE_ARITH;
+ USTPUTC(CTLARI, out);
+ if (state[level - 1].syntax == DQSYNTAX)
+ USTPUTC('"',out);
+ else
+ USTPUTC(' ',out);
+ goto parsearith_return;
+}
+
+} /* end of readtoken */
+
+
+/*
+ * Returns true if the text contains nothing to expand (no dollar signs
+ * or backquotes).
+ */
+
+static int
+noexpand(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(const char *name)
+{
+ const char *p;
+
+ p = name;
+ if (! is_name(*p))
+ return 0;
+ while (*++p) {
+ if (! is_in_name(*p))
+ return 0;
+ }
+ return 1;
+}
+
+
+int
+isassignment(const char *p)
+{
+ if (!is_name(*p))
+ return 0;
+ p++;
+ for (;;) {
+ if (*p == '=')
+ return 1;
+ else if (!is_in_name(*p))
+ return 0;
+ p++;
+ }
+}
+
+
+static void
+consumetoken(int token)
+{
+ if (readtoken() != token)
+ synexpect(token);
+}
+
+
+/*
+ * 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(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);
+}
+
+
+static void
+synerror(const char *msg)
+{
+ if (commandname)
+ outfmt(out2, "%s: %d: ", commandname, startlinno);
+ else if (arg0)
+ outfmt(out2, "%s: ", arg0);
+ outfmt(out2, "Syntax error: %s\n", msg);
+ error((char *)NULL);
+}
+
+static void
+setprompt(int which)
+{
+ whichprompt = which;
+ if (which == 0)
+ return;
+
+#ifndef NO_HISTORY
+ if (!el)
+#endif
+ {
+ out2str(getprompt(NULL));
+ flushout(out2);
+ }
+}
+
+static int
+pgetc_linecont(void)
+{
+ int c;
+
+ while ((c = pgetc_macro()) == '\\') {
+ c = pgetc();
+ if (c == '\n') {
+ plinno++;
+ if (doprompt)
+ setprompt(2);
+ else
+ setprompt(0);
+ } else {
+ pungetc();
+ /* Allow the backslash to be pushed back. */
+ pushstring("\\", 1, NULL);
+ return (pgetc());
+ }
+ }
+ return (c);
+}
+
+
+static struct passwd *
+getpwlogin(void)
+{
+ const char *login;
+
+ login = getlogin();
+ if (login == NULL)
+ return (NULL);
+
+ return (getpwnam(login));
+}
+
+
+static void
+getusername(char *name, size_t namelen)
+{
+ static char cached_name[MAXLOGNAME];
+ struct passwd *pw;
+ uid_t euid;
+
+ if (cached_name[0] == '\0') {
+ euid = geteuid();
+
+ /*
+ * Handle the case when there is more than one
+ * login with the same UID, or when the login
+ * returned by getlogin(2) does no longer match
+ * the current UID.
+ */
+ pw = getpwlogin();
+ if (pw == NULL || pw->pw_uid != euid)
+ pw = getpwuid(euid);
+
+ if (pw != NULL) {
+ strlcpy(cached_name, pw->pw_name,
+ sizeof(cached_name));
+ } else {
+ snprintf(cached_name, sizeof(cached_name),
+ "%u", euid);
+ }
+ }
+
+ strlcpy(name, cached_name, namelen);
+}
+
+
+/*
+ * called by editline -- any expansions to the prompt
+ * should be added here.
+ */
+char *
+getprompt(void *unused __unused)
+{
+ static char ps[PROMPTLEN];
+ const char *fmt;
+ const char *home;
+ const char *pwd;
+ size_t homelen;
+ int i, trim;
+ static char internal_error[] = "??";
+
+ /*
+ * Select prompt format.
+ */
+ switch (whichprompt) {
+ case 0:
+ fmt = "";
+ break;
+ case 1:
+ fmt = ps1val();
+ break;
+ case 2:
+ fmt = ps2val();
+ break;
+ default:
+ return internal_error;
+ }
+
+ /*
+ * Format prompt string.
+ */
+ for (i = 0; (i < PROMPTLEN - 1) && (*fmt != '\0'); i++, fmt++)
+ if (*fmt == '\\')
+ switch (*++fmt) {
+
+ /*
+ * Hostname.
+ *
+ * \h specifies just the local hostname,
+ * \H specifies fully-qualified hostname.
+ */
+ case 'h':
+ case 'H':
+ ps[i] = '\0';
+ gethostname(&ps[i], PROMPTLEN - i - 1);
+ ps[PROMPTLEN - 1] = '\0';
+ /* Skip to end of hostname. */
+ trim = (*fmt == 'h') ? '.' : '\0';
+ while ((ps[i] != '\0') && (ps[i] != trim))
+ i++;
+ --i;
+ break;
+
+ /*
+ * User name.
+ */
+ case 'u':
+ ps[i] = '\0';
+ getusername(&ps[i], PROMPTLEN - i);
+ /* Skip to end of username. */
+ while (ps[i + 1] != '\0')
+ i++;
+ break;
+
+ /*
+ * Working directory.
+ *
+ * \W specifies just the final component,
+ * \w specifies the entire path.
+ */
+ case 'W':
+ case 'w':
+ pwd = lookupvar("PWD");
+ if (pwd == NULL || *pwd == '\0')
+ pwd = "?";
+ if (*fmt == 'W' &&
+ *pwd == '/' && pwd[1] != '\0')
+ strlcpy(&ps[i], strrchr(pwd, '/') + 1,
+ PROMPTLEN - i);
+ else {
+ home = lookupvar("HOME");
+ if (home != NULL)
+ homelen = strlen(home);
+ if (home != NULL &&
+ strcmp(home, "/") != 0 &&
+ strncmp(pwd, home, homelen) == 0 &&
+ (pwd[homelen] == '/' ||
+ pwd[homelen] == '\0')) {
+ strlcpy(&ps[i], "~",
+ PROMPTLEN - i);
+ strlcpy(&ps[i + 1],
+ pwd + homelen,
+ PROMPTLEN - i - 1);
+ } else {
+ strlcpy(&ps[i], pwd, PROMPTLEN - i);
+ }
+ }
+ /* Skip to end of path. */
+ while (ps[i + 1] != '\0')
+ i++;
+ break;
+
+ /*
+ * Superuser status.
+ *
+ * '$' for normal users, '#' for root.
+ */
+ case '$':
+ ps[i] = (geteuid() != 0) ? '$' : '#';
+ break;
+
+ /*
+ * A literal \.
+ */
+ case '\\':
+ ps[i] = '\\';
+ break;
+
+ /*
+ * Emit unrecognized formats verbatim.
+ */
+ default:
+ ps[i] = '\\';
+ if (i < PROMPTLEN - 2)
+ ps[++i] = *fmt;
+ break;
+ }
+ else
+ ps[i] = *fmt;
+ ps[i] = '\0';
+ return (ps);
+}
+
+
+const char *
+expandstr(const char *ps)
+{
+ union node n;
+ struct jmploc jmploc;
+ struct jmploc *const savehandler = handler;
+ const int saveprompt = doprompt;
+ struct parsefile *const savetopfile = getcurrentfile();
+ struct parser_temp *const saveparser_temp = parser_temp;
+ const char *result = NULL;
+
+ if (!setjmp(jmploc.loc)) {
+ handler = &jmploc;
+ parser_temp = NULL;
+ setinputstring(ps, 1);
+ doprompt = 0;
+ readtoken1(pgetc(), DQSYNTAX, NOEOFMARK, 0);
+ if (backquotelist != NULL)
+ error("Command substitution not allowed here");
+
+ n.narg.type = NARG;
+ n.narg.next = NULL;
+ n.narg.text = wordtext;
+ n.narg.backquote = backquotelist;
+
+ expandarg(&n, NULL, 0);
+ result = stackblock();
+ INTOFF;
+ }
+ handler = savehandler;
+ doprompt = saveprompt;
+ popfilesupto(savetopfile);
+ if (parser_temp != saveparser_temp) {
+ parser_temp_free_all();
+ parser_temp = saveparser_temp;
+ }
+ if (result != NULL) {
+ INTON;
+ } else if (exception == EXINT)
+ raise(SIGINT);
+ return result;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-14 09:59:51 +0000