| /*- |
| * Copyright (c) 1991 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. |
| */ |
| |
| #ifndef lint |
| /*static char sccsid[] = "from: @(#)parser.c 5.3 (Berkeley) 4/12/91";*/ |
| static char rcsid[] = "parser.c,v 1.10 1993/09/09 01:21:43 cgd Exp"; |
| #endif /* not lint */ |
| |
| #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" |
| |
| |
| /* |
| * Shell command parser. |
| */ |
| |
| #define EOFMARKLEN 79 |
| |
| /* values returned by readtoken */ |
| #include "token.def" |
| |
| |
| |
| 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 */ |
| 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 */ |
| |
| |
| #define GDB_HACK 1 /* avoid local declarations which gdb can't handle */ |
| #ifdef GDB_HACK |
| static const char argvars[5] = {CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'}; |
| static const char types[] = "}-+?="; |
| #endif |
| |
| 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 void parsefname (void); |
| STATIC void parseheredoc (void); |
| STATIC int readtoken (void); |
| STATIC int readtoken1 (int, char const *, char *, int); |
| STATIC int peektoken(void); |
| STATIC void attyline (void); |
| STATIC int noexpand (char *); |
| STATIC void synexpect (int); |
| STATIC void synerror (char *); |
| |
| #if ATTY |
| STATIC void putprompt (char *); |
| #else /* not ATTY */ |
| #define putprompt(s) out2str(s) |
| #endif |
| |
| |
| |
| |
| /* |
| * Read and parse a command. Returns NEOF on end of file. (NULL is a |
| * valid parse tree indicating a blank line.) |
| */ |
| |
| union node * |
| parsecmd(interact) { |
| int t; |
| |
| doprompt = interact; |
| if (doprompt) |
| putprompt(ps1val()); |
| needprompt = 0; |
| if ((t = readtoken()) == TEOF) |
| return NEOF; |
| if (t == TNL) |
| return NULL; |
| tokpushback++; |
| return list(1); |
| } |
| |
| |
| STATIC union node * |
| list(nlflag) { |
| union node *n1, *n2, *n3; |
| |
| checkkwd = 2; |
| if (nlflag == 0 && tokendlist[peektoken()]) |
| return NULL; |
| n1 = andor(); |
| for (;;) { |
| switch (readtoken()) { |
| case TBACKGND: |
| if (n1->type == NCMD || n1->type == NPIPE) { |
| n1->ncmd.backgnd = 1; |
| } else if (n1->type == NREDIR) { |
| n1->type = NBACKGND; |
| } else { |
| n3 = (union node *)stalloc(sizeof (struct nredir)); |
| n3->type = NBACKGND; |
| n3->nredir.n = n1; |
| n3->nredir.redirect = NULL; |
| n1 = n3; |
| } |
| goto tsemi; |
| case TNL: |
| tokpushback++; |
| /* fall through */ |
| tsemi: case TSEMI: |
| if (readtoken() == TNL) { |
| parseheredoc(); |
| if (nlflag) |
| return n1; |
| } else { |
| tokpushback++; |
| } |
| checkkwd = 2; |
| if (tokendlist[peektoken()]) |
| return n1; |
| n2 = andor(); |
| n3 = (union node *)stalloc(sizeof (struct nbinary)); |
| n3->type = NSEMI; |
| n3->nbinary.ch1 = n1; |
| n3->nbinary.ch2 = n2; |
| n1 = n3; |
| 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; |
| |
| n1 = pipeline(); |
| for (;;) { |
| if ((t = readtoken()) == TAND) { |
| t = NAND; |
| } else if (t == TOR) { |
| t = NOR; |
| } else { |
| tokpushback++; |
| return n1; |
| } |
| 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, *pipenode; |
| struct nodelist *lp, *prev; |
| |
| 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)); |
| lp->n = command(); |
| prev->next = lp; |
| } while (readtoken() == TPIPE); |
| lp->next = NULL; |
| n1 = pipenode; |
| } |
| tokpushback++; |
| return n1; |
| } |
| |
| |
| |
| STATIC union node * |
| command() { |
| union node *n1, *n2; |
| union node *ap, **app; |
| union node *cp, **cpp; |
| union node *redir, **rpp; |
| int t; |
| |
| checkkwd = 2; |
| redir = 0; |
| 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; |
| /* A newline or semicolon is required here to end |
| the list. */ |
| if (lasttoken != TNL && lasttoken != TSEMI) |
| synexpect(-1); |
| } else { |
| #ifndef GDB_HACK |
| static const char argvars[5] = {CTLVAR, VSNORMAL|VSQUOTE, |
| '@', '=', '\0'}; |
| #endif |
| n2 = (union node *)stalloc(sizeof (struct narg)); |
| n2->type = NARG; |
| n2->narg.text = (char *)argvars; |
| n2->narg.backquote = NULL; |
| n2->narg.next = NULL; |
| n1->nfor.args = n2; |
| /* Many shells accept an optional semicolon here, but |
| POSIX says we should not, so we don't. An optional |
| newline is OK here, but that is handled by the |
| checkkwd = 2 assignment below. */ |
| 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; |
| while (checkkwd = 2, readtoken() == TWORD) { |
| *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 (readtoken() != TPIPE) |
| break; |
| app = &ap->narg.next; |
| if (readtoken() != TWORD) |
| synexpect(TWORD); |
| } |
| ap->narg.next = NULL; |
| if (lasttoken != TRP) |
| synexpect(TRP); |
| cp->nclist.body = list(0); |
| if ((t = readtoken()) == TESAC) |
| tokpushback++; |
| else if (t != TENDCASE) |
| synexpect(TENDCASE); |
| cpp = &cp->nclist.next; |
| } |
| *cpp = NULL; |
| if (lasttoken != TESAC) |
| synexpect(TESAC); |
| 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 TNL: |
| /* Handle EOF like other simple commands, too. */ |
| case TEOF: |
| case TWORD: |
| tokpushback++; |
| return simplecmd(rpp, redir); |
| 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 (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; |
| |
| /* 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; |
| 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 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) { |
| if (is_digit(wordtext[0])) |
| n->ndup.dupfd = digit_val(wordtext[0]); |
| else if (wordtext[0] == '-') |
| n->ndup.dupfd = -1; |
| else |
| goto bad; |
| if (wordtext[1] != '\0') { |
| bad: |
| synerror("Bad fd number"); |
| } |
| } else { |
| n->nfile.fname = (union node *)stalloc(sizeof (struct narg)); |
| n = n->nfile.fname; |
| n->type = NARG; |
| n->narg.next = NULL; |
| n->narg.text = wordtext; |
| n->narg.backquote = backquotelist; |
| } |
| } |
| |
| |
| /* |
| * Input any here documents. |
| */ |
| |
| STATIC void |
| parseheredoc() { |
| struct heredoc *here; |
| union node *n; |
| |
| while (heredoclist) { |
| here = heredoclist; |
| heredoclist = here->next; |
| if (needprompt) { |
| putprompt(ps2val()); |
| 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 xxreadtoken(); |
| |
| STATIC int |
| readtoken() { |
| int t; |
| #ifdef DEBUG |
| int alreadyseen = tokpushback; |
| #endif |
| |
| t = xxreadtoken(); |
| |
| if (checkkwd) { |
| /* |
| * eat newlines |
| */ |
| if (checkkwd == 2) { |
| checkkwd = 0; |
| while (t == TNL) { |
| parseheredoc(); |
| t = xxreadtoken(); |
| } |
| } else |
| checkkwd = 0; |
| /* |
| * check for keywords |
| */ |
| if (t == TWORD && !quoteflag) { |
| register 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])); |
| break; |
| } |
| } |
| } |
| } |
| #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() { |
| register c; |
| |
| if (tokpushback) { |
| tokpushback = 0; |
| return lasttoken; |
| } |
| if (needprompt) { |
| putprompt(ps2val()); |
| 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) |
| putprompt(ps2val()); |
| 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:;} |
| |
| STATIC int |
| readtoken1(firstc, syntax, eofmark, striptabs) |
| int firstc; |
| char const *syntax; |
| char *eofmark; |
| int striptabs; |
| { |
| register c = firstc; |
| register char *out; |
| int len; |
| char line[EOFMARKLEN + 1]; |
| struct nodelist *bqlist; |
| int quotef; |
| int dblquote; |
| int varnest; |
| int oldstyle; |
| |
| startlinno = plinno; |
| dblquote = 0; |
| if (syntax == DQSYNTAX) |
| dblquote = 1; |
| quotef = 0; |
| bqlist = NULL; |
| varnest = 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) { |
| putprompt(ps2val()); |
| } |
| c = pgetc(); |
| goto loop; /* continue outer loop */ |
| case CWORD: |
| USTPUTC(c, out); |
| break; |
| case CCTL: |
| if (eofmark == NULL || dblquote) |
| USTPUTC(CTLESC, out); |
| USTPUTC(c, out); |
| break; |
| case CBACK: /* backslash */ |
| c = pgetc(); |
| if (c == PEOF) { |
| USTPUTC('\\', out); |
| pungetc(); |
| } else if (c == '\n') { |
| if (doprompt) |
| putprompt(ps2val()); |
| } else { |
| if (dblquote && c != '\\' && c != '`' && c != '$' |
| && (c != '"' || eofmark != NULL)) |
| USTPUTC('\\', out); |
| if (SQSYNTAX[c] == CCTL) |
| USTPUTC(CTLESC, out); |
| USTPUTC(c, out); |
| quotef++; |
| } |
| break; |
| case CSQUOTE: |
| syntax = SQSYNTAX; |
| break; |
| case CDQUOTE: |
| syntax = DQSYNTAX; |
| dblquote = 1; |
| break; |
| case CENDQUOTE: |
| if (eofmark) { |
| USTPUTC(c, out); |
| } else { |
| syntax = BASESYNTAX; |
| quotef++; |
| dblquote = 0; |
| } |
| break; |
| case CVAR: /* '$' */ |
| PARSESUB(); /* parse substitution */ |
| break; |
| case CENDVAR: /* '}' */ |
| if (varnest > 0) { |
| varnest--; |
| USTPUTC(CTLENDVAR, out); |
| } else { |
| USTPUTC(c, 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 != 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) { |
| register 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 { |
| ppushback(line, strlen(line)); |
| } |
| } |
| } |
| } |
| 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 { |
| np->type = NTO; |
| pungetc(); |
| } |
| } else { /* c == '<' */ |
| np->nfile.fd = 0; |
| c = pgetc(); |
| 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()) == '-') { |
| heredoc->striptabs = 1; |
| } else { |
| heredoc->striptabs = 0; |
| pungetc(); |
| } |
| } else if (c == '&') |
| np->type = NFROMFD; |
| else { |
| np->type = NFROM; |
| pungetc(); |
| } |
| } |
| 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; |
| #ifndef GDB_HACK |
| static const char types[] = "}-+?="; |
| #endif |
| |
| c = pgetc(); |
| if (c != '(' && c != '{' && !is_name(c) && !is_special(c)) { |
| USTPUTC('$', out); |
| pungetc(); |
| } else if (c == '(') { /* $(command) */ |
| PARSEBACKQNEW(); |
| } else { |
| USTPUTC(CTLVAR, out); |
| typeloc = out - stackblock(); |
| USTPUTC(VSNORMAL, out); |
| subtype = VSNORMAL; |
| if (c == '{') { |
| c = pgetc(); |
| subtype = 0; |
| } |
| if (is_name(c)) { |
| do { |
| STPUTC(c, out); |
| c = pgetc(); |
| } while (is_in_name(c)); |
| } else { |
| if (! is_special(c)) |
| badsub: synerror("Bad substitution"); |
| USTPUTC(c, out); |
| c = pgetc(); |
| } |
| STPUTC('=', out); |
| flags = 0; |
| if (subtype == 0) { |
| if (c == ':') { |
| flags = VSNUL; |
| c = pgetc(); |
| } |
| p = strchr(types, c); |
| if (p == NULL) |
| goto badsub; |
| subtype = p - types + VSNORMAL; |
| } else { |
| pungetc(); |
| } |
| if (dblquote) |
| flags |= VSQUOTE; |
| *(stackblock() + typeloc) = subtype | flags; |
| if (subtype != VSNORMAL) |
| varnest++; |
| } |
| goto parsesub_return; |
| } |
| |
| |
| /* |
| * Called to parse command substitutions. Newstyle is set if the command |
| * is enclosed inside $(...); nlpp is a pointer to the head of the linked |
| * list of commands (passed by reference), and savelen is the number of |
| * characters on the top of the stack which must be preserved. |
| */ |
| |
| parsebackq: { |
| struct nodelist **nlpp; |
| int savepbq; |
| union node *n; |
| char *volatile str; |
| struct jmploc jmploc; |
| struct jmploc *volatile savehandler; |
| int savelen; |
| |
| savepbq = parsebackquote; |
| if (setjmp(jmploc.loc)) { |
| if (str) |
| ckfree(str); |
| parsebackquote = 0; |
| handler = savehandler; |
| longjmp(handler->loc, 1); |
| } |
| INTOFF; |
| str = NULL; |
| savelen = out - stackblock(); |
| if (savelen > 0) { |
| str = ckmalloc(savelen); |
| bcopy(stackblock(), str, savelen); |
| } |
| savehandler = handler; |
| handler = &jmploc; |
| INTON; |
| if (oldstyle) { |
| /* We must read until the closing backquote, giving special |
| treatment to some slashes, and then push the string and |
| reread it as input, interpreting it normally. */ |
| register char *out; |
| register c; |
| int savelen; |
| char *str; |
| |
| STARTSTACKSTR(out); |
| while ((c = pgetc ()) != '`') { |
| if (c == '\\') { |
| c = pgetc (); |
| if (c != '\\' && c != '`' && c != '$' |
| && (!dblquote || c != '"')) |
| STPUTC('\\', out); |
| } |
| STPUTC(c, out); |
| } |
| STPUTC('\0', out); |
| savelen = out - stackblock(); |
| if (savelen > 0) { |
| str = ckmalloc(savelen); |
| bcopy(stackblock(), str, savelen); |
| } |
| setinputstring(str, 1); |
| } |
| nlpp = &bqlist; |
| while (*nlpp) |
| nlpp = &(*nlpp)->next; |
| *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist)); |
| (*nlpp)->next = NULL; |
| parsebackquote = oldstyle; |
| n = list(0); |
| if (!oldstyle && (readtoken() != TRP)) |
| synexpect(TRP); |
| (*nlpp)->n = n; |
| /* Start reading from old file again, and clear tokpushback since |
| any pushed back token from the string is no longer relevant. */ |
| if (oldstyle) { |
| popfile(); |
| tokpushback = 0; |
| } |
| while (stackblocksize() <= savelen) |
| growstackblock(); |
| STARTSTACKSTR(out); |
| if (str) { |
| bcopy(str, out, savelen); |
| STADJUST(savelen, out); |
| INTOFF; |
| ckfree(str); |
| str = NULL; |
| INTON; |
| } |
| parsebackquote = savepbq; |
| handler = savehandler; |
| USTPUTC(CTLBACKQ + dblquote, out); |
| if (oldstyle) |
| goto parsebackq_oldreturn; |
| else |
| goto parsebackq_newreturn; |
| } |
| |
| } /* end of readtoken */ |
| |
| |
| |
| #ifdef mkinit |
| RESET { |
| tokpushback = 0; |
| } |
| #endif |
| |
| |
| #if ATTY |
| /* |
| * Called to process a command generated by atty. We execute the line, |
| * and catch any errors that occur so they don't propagate outside of |
| * this routine. |
| */ |
| |
| STATIC void |
| attyline() { |
| char line[256]; |
| struct stackmark smark; |
| struct jmploc jmploc; |
| struct jmploc *volatile savehandler; |
| |
| if (pfgets(line, sizeof line) == NULL) |
| return; /* "can't happen" */ |
| if (setjmp(jmploc.loc)) { |
| if (exception == EXERROR) |
| out2str("\033]D\n"); |
| handler = savehandler; |
| longjmp(handler->loc, 1); |
| } |
| savehandler = handler; |
| handler = &jmploc; |
| setstackmark(&smark); |
| evalstring(line); |
| popstackmark(&smark); |
| handler = savehandler; |
| doprompt = 1; |
| } |
| |
| |
| /* |
| * Output a prompt for atty. We output the prompt as part of the |
| * appropriate escape sequence. |
| */ |
| |
| STATIC void |
| putprompt(s) |
| char *s; |
| { |
| register char *p; |
| |
| if (attyset() && ! equal(termval(), "emacs")) { |
| if (strchr(s, '\7')) |
| out2c('\7'); |
| out2str("\033]P1;"); |
| for (p = s ; *p ; p++) { |
| if ((unsigned)(*p - ' ') <= '~' - ' ') |
| out2c(*p); |
| } |
| out2c('\n'); |
| } else { |
| out2str(s); |
| } |
| } |
| #endif |
| |
| |
| |
| /* |
| * Returns true if the text contains nothing to expand (no dollar signs |
| * or backquotes). |
| */ |
| |
| STATIC int |
| noexpand(text) |
| char *text; |
| { |
| register char *p; |
| register char c; |
| |
| p = text; |
| while ((c = *p++) != '\0') { |
| if (c == CTLESC) |
| p++; |
| else if (BASESYNTAX[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(name) |
| char *name; |
| { |
| register 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) { |
| 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(msg) |
| char *msg; |
| { |
| if (commandname) |
| outfmt(&errout, "%s: %d: ", commandname, startlinno); |
| outfmt(&errout, "Syntax error: %s\n", msg); |
| error((char *)NULL); |
| } |