示例#1
0
const char* FAST_FUNC
endofname(const char *name)
{
	if (!is_name(*name))
		return name;
	while (*++name) {
		if (!is_in_name(*name))
			break;
	}
	return name;
}
示例#2
0
文件: parser.c 项目: 7shi/minix-tools
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;
}
示例#3
0
文件: var.c 项目: dezelin/kBuild
void
setvar(shinstance *psh, const char *name, const char *val, int flags)
{
    const char *p;
    const char *q;
    char *d;
    size_t len;
    int namelen;
    char *nameeq;
    int isbad;

    isbad = 0;
    p = name;
    if (! is_name(*p))
        isbad = 1;
    p++;
    for (;;) {
        if (! is_in_name(*p)) {
            if (*p == '\0' || *p == '=')
                break;
            isbad = 1;
        }
        p++;
    }
    namelen = (int)(p - name);
    if (isbad)
        error(psh, "%.*s: bad variable name", namelen, name);
    len = namelen + 2;		/* 2 is space for '=' and '\0' */
    if (val == NULL) {
        flags |= VUNSET;
    } else {
        len += strlen(val);
    }
    d = nameeq = ckmalloc(psh, len);
    q = name;
    while (--namelen >= 0)
        *d++ = *q++;
    *d++ = '=';
    *d = '\0';
    if (val)
        scopy(val, d);
    setvareq(psh, nameeq, flags);
}
示例#4
0
文件: var.c 项目: 0xffea/MINIX3
void
setvar(char *name, char *val, int flags)
{
	char *p, *q;
	int len;
	int namelen;
	char *nameeq;
	int isbad;

	isbad = 0;
	p = name;
	if (! is_name(*p))
		isbad = 1;
	p++;
	for (;;) {
		if (! is_in_name(*p)) {
			if (*p == '\0' || *p == '=')
				break;
			isbad = 1;
		}
		p++;
	}
	namelen = p - name;
	if (isbad)
		error("%.*s: bad variable name", namelen, name);
	len = namelen + 2;		/* 2 is space for '=' and '\0' */
	if (val == NULL) {
		flags |= VUNSET;
	} else {
		len += strlen(val);
	}
	p = nameeq = ckmalloc(len);
	q = name;
	while (--namelen >= 0)
		*p++ = *q++;
	*p++ = '=';
	*p = '\0';
	if (val)
		scopy(val, p);
	setvareq(nameeq, flags);
}
示例#5
0
int
yylex(void)
{
    int value;
    const char *buf = arith_buf;
    char *end;
    const char *p;

    for (;;) {
        value = *buf;
        switch (value) {
        case ' ':
        case '\t':
        case '\n':
            buf++;
            continue;
        default:
            return ARITH_BAD;
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
            yylval.val = strtoarith_t(buf, &end, 0);
            arith_buf = end;
            return ARITH_NUM;
        case 'A':
        case 'B':
        case 'C':
        case 'D':
        case 'E':
        case 'F':
        case 'G':
        case 'H':
        case 'I':
        case 'J':
        case 'K':
        case 'L':
        case 'M':
        case 'N':
        case 'O':
        case 'P':
        case 'Q':
        case 'R':
        case 'S':
        case 'T':
        case 'U':
        case 'V':
        case 'W':
        case 'X':
        case 'Y':
        case 'Z':
        case '_':
        case 'a':
        case 'b':
        case 'c':
        case 'd':
        case 'e':
        case 'f':
        case 'g':
        case 'h':
        case 'i':
        case 'j':
        case 'k':
        case 'l':
        case 'm':
        case 'n':
        case 'o':
        case 'p':
        case 'q':
        case 'r':
        case 's':
        case 't':
        case 'u':
        case 'v':
        case 'w':
        case 'x':
        case 'y':
        case 'z':
            p = buf;
            while (buf++, is_in_name(*buf))
                ;
            yylval.name = stalloc(buf - p + 1);
            memcpy(yylval.name, p, buf - p);
            yylval.name[buf - p] = '\0';
            value = ARITH_VAR;
            goto out;
        case '=':
            value += ARITH_ASS - '=';
checkeq:
            buf++;
checkeqcur:
            if (*buf != '=')
                goto out;
            value += 11;
            break;
        case '>':
            switch (*++buf) {
            case '=':
                value += ARITH_GE - '>';
                break;
            case '>':
                value += ARITH_RSHIFT - '>';
                goto checkeq;
            default:
                value += ARITH_GT - '>';
                goto out;
            }
            break;
        case '<':
            switch (*++buf) {
            case '=':
                value += ARITH_LE - '<';
                break;
            case '<':
                value += ARITH_LSHIFT - '<';
                goto checkeq;
            default:
                value += ARITH_LT - '<';
                goto out;
            }
            break;
        case '|':
            if (*++buf != '|') {
                value += ARITH_BOR - '|';
                goto checkeqcur;
            }
            value += ARITH_OR - '|';
            break;
        case '&':
            if (*++buf != '&') {
                value += ARITH_BAND - '&';
                goto checkeqcur;
            }
            value += ARITH_AND - '&';
            break;
        case '!':
            if (*++buf != '=') {
                value += ARITH_NOT - '!';
                goto out;
            }
            value += ARITH_NE - '!';
            break;
        case 0:
            goto out;
        case '(':
            value += ARITH_LPAREN - '(';
            break;
        case ')':
            value += ARITH_RPAREN - ')';
            break;
        case '*':
            value += ARITH_MUL - '*';
            goto checkeq;
        case '/':
            value += ARITH_DIV - '/';
            goto checkeq;
        case '%':
            value += ARITH_REM - '%';
            goto checkeq;
        case '+':
            value += ARITH_ADD - '+';
            goto checkeq;
        case '-':
            value += ARITH_SUB - '-';
            goto checkeq;
        case '~':
            value += ARITH_BNOT - '~';
            break;
        case '^':
            value += ARITH_BXOR - '^';
            goto checkeq;
        case '?':
            value += ARITH_QMARK - '?';
            break;
        case ':':
            value += ARITH_COLON - ':';
            break;
        }
        break;
    }

    buf++;
out:
    arith_buf = buf;
    return value;
}
示例#6
0
static void
evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
{
	struct stackmark smark;
	union node *argp;
	struct arglist arglist;
	struct arglist varlist;
	char **argv;
	int argc;
	char **envp;
	int varflag;
	struct strlist *sp;
	int mode;
	int pip[2];
	struct cmdentry cmdentry;
	struct job *jp;
	struct jmploc jmploc;
	struct jmploc *savehandler;
	char *savecmdname;
	struct shparam saveparam;
	struct localvar *savelocalvars;
	volatile int e;
	char *lastarg;
	int realstatus;
	int do_clearcmdentry;

	/* First expand the arguments. */
	TRACE(("evalcommand(%p, %d) called\n", (void *)cmd, flags));
	setstackmark(&smark);
	arglist.lastp = &arglist.list;
	varlist.lastp = &varlist.list;
	varflag = 1;
	do_clearcmdentry = 0;
	oexitstatus = exitstatus;
	exitstatus = 0;
	for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
		char *p = argp->narg.text;
		if (varflag && is_name(*p)) {
			do {
				p++;
			} while (is_in_name(*p));
			if (*p == '=') {
				expandarg(argp, &varlist, EXP_VARTILDE);
				continue;
			}
		}
		expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
		varflag = 0;
	}
	*arglist.lastp = NULL;
	*varlist.lastp = NULL;
	expredir(cmd->ncmd.redirect);
	argc = 0;
	for (sp = arglist.list ; sp ; sp = sp->next)
		argc++;
	argv = stalloc(sizeof (char *) * (argc + 1));

	for (sp = arglist.list ; sp ; sp = sp->next) {
		TRACE(("evalcommand arg: %s\n", sp->text));
		*argv++ = sp->text;
	}
	*argv = NULL;
	lastarg = NULL;
	if (iflag && funcnest == 0 && argc > 0)
		lastarg = argv[-1];
	argv -= argc;

	/* Print the command if xflag is set. */
	if (xflag) {
		char sep = 0;
		const char *p;
		out2str(ps4val());
		for (sp = varlist.list ; sp ; sp = sp->next) {
			if (sep != 0)
				outc(' ', &errout);
			p = sp->text;
			while (*p != '=' && *p != '\0')
				out2c(*p++);
			if (*p != '\0') {
				out2c(*p++);
				out2qstr(p);
			}
			sep = ' ';
		}
		for (sp = arglist.list ; sp ; sp = sp->next) {
			if (sep != 0)
				outc(' ', &errout);
			/* Disambiguate command looking like assignment. */
			if (sp == arglist.list &&
					strchr(sp->text, '=') != NULL &&
					strchr(sp->text, '\'') == NULL) {
				out2c('\'');
				out2str(sp->text);
				out2c('\'');
			} else
				out2qstr(sp->text);
			sep = ' ';
		}
		outc('\n', &errout);
		flushout(&errout);
	}

	/* Now locate the command. */
	if (argc == 0) {
		/* Variable assignment(s) without command */
		cmdentry.cmdtype = CMDBUILTIN;
		cmdentry.u.index = BLTINCMD;
		cmdentry.special = 1;
	} else {
		static const char PATH[] = "PATH=";
		char *path = pathval();

		/*
		 * Modify the command lookup path, if a PATH= assignment
		 * is present
		 */
		for (sp = varlist.list ; sp ; sp = sp->next)
			if (strncmp(sp->text, PATH, sizeof(PATH) - 1) == 0) {
				path = sp->text + sizeof(PATH) - 1;
				/*
				 * On `PATH=... command`, we need to make
				 * sure that the command isn't using the
				 * non-updated hash table of the outer PATH
				 * setting and we need to make sure that
				 * the hash table isn't filled with items
				 * from the temporary setting.
				 *
				 * It would be better to forbit using and
				 * updating the table while this command
				 * runs, by the command finding mechanism
				 * is heavily integrated with hash handling,
				 * so we just delete the hash before and after
				 * the command runs. Partly deleting like
				 * changepatch() does doesn't seem worth the
				 * bookinging effort, since most such runs add
				 * directories in front of the new PATH.
				 */
				clearcmdentry(0);
				do_clearcmdentry = 1;
			}

		find_command(argv[0], &cmdentry, 1, path);
		if (cmdentry.cmdtype == CMDUNKNOWN) {	/* command not found */
			exitstatus = 127;
			flushout(&errout);
			return;
		}
		/* implement the bltin builtin here */
		if (cmdentry.cmdtype == CMDBUILTIN && cmdentry.u.index == BLTINCMD) {
			for (;;) {
				argv++;
				if (--argc == 0)
					break;
				if ((cmdentry.u.index = find_builtin(*argv,
				    &cmdentry.special)) < 0) {
					outfmt(&errout, "%s: not found\n", *argv);
					exitstatus = 127;
					flushout(&errout);
					return;
				}
				if (cmdentry.u.index != BLTINCMD)
					break;
			}
		}
	}

	/* Fork off a child process if necessary. */
	if (cmd->ncmd.backgnd
	 || (cmdentry.cmdtype == CMDNORMAL
	    && ((flags & EV_EXIT) == 0 || have_traps()))
	 || ((flags & EV_BACKCMD) != 0
	    && (cmdentry.cmdtype != CMDBUILTIN
		 || cmdentry.u.index == CDCMD
		 || cmdentry.u.index == DOTCMD
		 || cmdentry.u.index == EVALCMD))
	 || (cmdentry.cmdtype == CMDBUILTIN &&
	    cmdentry.u.index == COMMANDCMD)) {
		jp = makejob(cmd, 1);
		mode = cmd->ncmd.backgnd;
		if (flags & EV_BACKCMD) {
			mode = FORK_NOJOB;
			if (pipe(pip) < 0)
				error("Pipe call failed: %s", strerror(errno));
		}
		if (forkshell(jp, cmd, mode) != 0)
			goto parent;	/* at end of routine */
		if (flags & EV_BACKCMD) {
			FORCEINTON;
			close(pip[0]);
			if (pip[1] != 1) {
				dup2(pip[1], 1);
				close(pip[1]);
			}
		}
		flags |= EV_EXIT;
	}

	/* This is the child process if a fork occurred. */
	/* Execute the command. */
	if (cmdentry.cmdtype == CMDFUNCTION) {
#ifdef DEBUG
		trputs("Shell function:  ");  trargs(argv);
#endif
		redirect(cmd->ncmd.redirect, REDIR_PUSH);
		saveparam = shellparam;
		shellparam.malloc = 0;
		shellparam.reset = 1;
		shellparam.nparam = argc - 1;
		shellparam.p = argv + 1;
		shellparam.optnext = NULL;
		INTOFF;
		savelocalvars = localvars;
		localvars = NULL;
		reffunc(cmdentry.u.func);
		INTON;
		savehandler = handler;
		if (setjmp(jmploc.loc)) {
			if (exception == EXSHELLPROC)
				freeparam(&saveparam);
			else {
				freeparam(&shellparam);
				shellparam = saveparam;
			}
			unreffunc(cmdentry.u.func);
			poplocalvars();
			localvars = savelocalvars;
			handler = savehandler;
			longjmp(handler->loc, 1);
		}
		handler = &jmploc;
		for (sp = varlist.list ; sp ; sp = sp->next)
			mklocal(sp->text);
		funcnest++;
		exitstatus = oexitstatus;
		if (flags & EV_TESTED)
			evaltree(getfuncnode(cmdentry.u.func), EV_TESTED);
		else
			evaltree(getfuncnode(cmdentry.u.func), 0);
		funcnest--;
		INTOFF;
		unreffunc(cmdentry.u.func);
		poplocalvars();
		localvars = savelocalvars;
		freeparam(&shellparam);
		shellparam = saveparam;
		handler = savehandler;
		popredir();
		INTON;
		if (evalskip == SKIPFUNC) {
			evalskip = 0;
			skipcount = 0;
		}
		if (flags & EV_EXIT)
			exitshell(exitstatus);
	} else if (cmdentry.cmdtype == CMDBUILTIN) {
#ifdef DEBUG
		trputs("builtin command:  ");  trargs(argv);
#endif
		mode = (cmdentry.u.index == EXECCMD)? 0 : REDIR_PUSH;
		if (flags == EV_BACKCMD) {
			memout.nleft = 0;
			memout.nextc = memout.buf;
			memout.bufsize = 64;
			mode |= REDIR_BACKQ;
		}
		savecmdname = commandname;
		cmdenviron = varlist.list;
		e = -1;
		savehandler = handler;
		if (setjmp(jmploc.loc)) {
			e = exception;
			exitstatus = (e == EXINT)? SIGINT+128 : 2;
			goto cmddone;
		}
		handler = &jmploc;
		redirect(cmd->ncmd.redirect, mode);
		if (cmdentry.special)
			listsetvar(cmdenviron);
		commandname = argv[0];
		argptr = argv + 1;
		nextopt_optptr = NULL;		/* initialize nextopt */
		builtin_flags = flags;
		exitstatus = (*builtinfunc[cmdentry.u.index])(argc, argv);
		flushall();
cmddone:
		cmdenviron = NULL;
		out1 = &output;
		out2 = &errout;
		freestdout();
		if (e != EXSHELLPROC) {
			commandname = savecmdname;
			if (flags & EV_EXIT) {
				exitshell(exitstatus);
			}
		}
		handler = savehandler;
		if (e != -1) {
			if ((e != EXERROR && e != EXEXEC)
			    || cmdentry.special)
				exraise(e);
			FORCEINTON;
		}
		if (cmdentry.u.index != EXECCMD)
			popredir();
		if (flags == EV_BACKCMD) {
			backcmd->buf = memout.buf;
			backcmd->nleft = memout.nextc - memout.buf;
			memout.buf = NULL;
		}
	} else {
#ifdef DEBUG
		trputs("normal command:  ");  trargs(argv);
#endif
		clearredir();
		redirect(cmd->ncmd.redirect, 0);
		for (sp = varlist.list ; sp ; sp = sp->next)
			setvareq(sp->text, VEXPORT|VSTACK);
		envp = environment();
		shellexec(argv, envp, pathval(), cmdentry.u.index);
		/*NOTREACHED*/
	}
	goto out;

parent:	/* parent process gets here (if we forked) */
	if (mode == FORK_FG) {	/* argument to fork */
		INTOFF;
		exitstatus = waitforjob(jp, &realstatus);
		INTON;
		if (iflag && loopnest > 0 && WIFSIGNALED(realstatus)) {
			evalskip = SKIPBREAK;
			skipcount = loopnest;
		}
	} else if (mode == FORK_NOJOB) {
		backcmd->fd = pip[0];
		close(pip[1]);
		backcmd->jp = jp;
	}

out:
	if (lastarg)
		setvar("_", lastarg, 0);
	if (do_clearcmdentry)
		clearcmdentry(0);
	popstackmark(&smark);
}
示例#7
0
文件: parser.c 项目: 7shi/minix-tools
STATIC int
readtoken1(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 oldstyle;
	char const *prevsyntax;	/* syntax before arithmetic */
	int synentry;
#if __GNUC__
	/* Avoid longjmp clobbering */
	(void) &out;
	(void) &quotef;
	(void) &dblquote;
	(void) &varnest;
	(void) &arinest;
	(void) &parenlevel;
	(void) &oldstyle;
	(void) &prevsyntax;
	(void) &syntax;
	(void) &synentry;
#endif

	startlinno = plinno;
	dblquote = 0;
	if (syntax == DQSYNTAX)
		dblquote = 1;
	quotef = 0;
	bqlist = NULL;
	varnest = 0;
	arinest = 0;
	parenlevel = 0;

	STARTSTACKSTR(out);
	loop: {	/* for each line, until end of word */
		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 */

			synentry = syntax[c];

			switch(synentry) {
			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)
					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 != '$' &&
					    (c != '"' || eofmark != NULL))
						USTPUTC('\\', out);
					if (SQSYNTAX[c] == CCTL)
						USTPUTC(CTLESC, out);
					else if (eofmark == NULL)
						USTPUTC(CTLQUOTEMARK, out);
					USTPUTC(c, out);
					quotef++;
				}
				break;
			case CSQUOTE:
				if (eofmark == NULL)
					USTPUTC(CTLQUOTEMARK, out);
				syntax = SQSYNTAX;
				break;
			case CDQUOTE:
				if (eofmark == NULL)
					USTPUTC(CTLQUOTEMARK, out);
				syntax = DQSYNTAX;
				dblquote = 1;
				break;
			case CENDQUOTE:
				if (eofmark != NULL && arinest == 0 &&
				    varnest == 0) {
					USTPUTC(c, out);
				} else {
					if (arinest) {
						syntax = ARISYNTAX;
						dblquote = 0;
					} else if (eofmark == NULL) {
						syntax = BASESYNTAX;
						dblquote = 0;
					}
					quotef++;
				}
				break;
			case CVAR:	/* '$' */
				PARSESUB();		/* parse substitution */
				break;
			case CENDVAR:	/* '}' */
				if (varnest > 0) {
					varnest--;
					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 = NCLOBBER;
		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 if (c == '>')
			np->type = NFROMTO;
		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
       int bracketed_name = 0; /* used to handle ${[0-9]*} variables */

	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 == '{') {
			bracketed_name = 1;
			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)) {
			if (bracketed_name) {
				do {
					STPUTC(c, out);
					c = pgetc();
				} while (is_digit(c));
			} else {
				STPUTC(c, out);
				c = pgetc();
			}
		} else {
			if (! is_special(c))
badsub:				synerror("Bad substitution");
			USTPUTC(c, out);
			c = pgetc();
		}
		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 (subtype != VSLENGTH && (dblquote || arinest))
			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;
	int saveprompt;
#if __GNUC__
	/* Avoid longjmp clobbering */
	(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 *out;
                int c;
                int savelen;
                char *str;


                STARTSTACKSTR(out);
		for (;;) {
			if (needprompt) {
				setprompt(2);
				needprompt = 0;
			}
			switch (c = pgetc()) {
			case '`':
				goto done;

			case '\\':
                                if ((c = 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 (c != '\\' && c != '`' && c != '$'
                                    && (!dblquote || c != '"'))
                                        STPUTC('\\', out);
				break;

			case '\n':
				plinno++;
				needprompt = doprompt;
				break;

			case PEOF:
			        startlinno = plinno;
				synerror("EOF in backquote substitution");
 				break;

			default:
				break;
			}
			STPUTC(c, out);
                }
done:
                STPUTC('\0', out);
                savelen = out - stackblock();
                if (savelen > 0) {
                        str = ckmalloc(savelen);
                        memcpy(str, stackblock(), savelen);
			setinputstring(str, 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 */
示例#8
0
文件: eval.c 项目: dezelin/kBuild
STATIC void
evalcommand(shinstance *psh, union node *cmd, int flags, struct backcmd *backcmd)
{
	struct stackmark smark;
	union node *argp;
	struct arglist arglist;
	struct arglist varlist;
	char **argv;
	int argc;
	char **envp;
	int varflag;
	struct strlist *sp;
	int mode;
	int pip[2];
	struct cmdentry cmdentry;
	struct job *jp;
	struct jmploc jmploc;
	struct jmploc *volatile savehandler;
	char *volatile savecmdname;
	volatile struct shparam saveparam;
	struct localvar *volatile savelocalvars;
	volatile int e;
	char *lastarg;
	const char *path = pathval(psh);
	volatile int temp_path;
#if __GNUC__
	/* Avoid longjmp clobbering */
	(void) &argv;
	(void) &argc;
	(void) &lastarg;
	(void) &flags;
#endif

	psh->vforked = 0;
	/* First expand the arguments. */
	TRACE((psh, "evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
	setstackmark(psh, &smark);
	psh->back_exitstatus = 0;

	arglist.lastp = &arglist.list;
	varflag = 1;
	/* Expand arguments, ignoring the initial 'name=value' ones */
	for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
		char *p = argp->narg.text;
		if (varflag && is_name(*p)) {
			do {
				p++;
			} while (is_in_name(*p));
			if (*p == '=')
				continue;
		}
		expandarg(psh, argp, &arglist, EXP_FULL | EXP_TILDE);
		varflag = 0;
	}
	*arglist.lastp = NULL;

	expredir(psh, cmd->ncmd.redirect);

	/* Now do the initial 'name=value' ones we skipped above */
	varlist.lastp = &varlist.list;
	for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
		char *p = argp->narg.text;
		if (!is_name(*p))
			break;
		do
			p++;
		while (is_in_name(*p));
		if (*p != '=')
			break;
		expandarg(psh, argp, &varlist, EXP_VARTILDE);
	}
	*varlist.lastp = NULL;

	argc = 0;
	for (sp = arglist.list ; sp ; sp = sp->next)
		argc++;
	argv = stalloc(psh, sizeof (char *) * (argc + 1));

	for (sp = arglist.list ; sp ; sp = sp->next) {
		TRACE((psh, "evalcommand arg: %s\n", sp->text));
		*argv++ = sp->text;
	}
	*argv = NULL;
	lastarg = NULL;
	if (iflag(psh) && psh->funcnest == 0 && argc > 0)
		lastarg = argv[-1];
	argv -= argc;

	/* Print the command if xflag is set. */
	if (xflag(psh)) {
		char sep = 0;
		out2str(psh, ps4val(psh));
		for (sp = varlist.list ; sp ; sp = sp->next) {
			if (sep != 0)
				outc(sep, &psh->errout);
			out2str(psh, sp->text);
			sep = ' ';
		}
		for (sp = arglist.list ; sp ; sp = sp->next) {
			if (sep != 0)
				outc(sep, &psh->errout);
			out2str(psh, sp->text);
			sep = ' ';
		}
		outc('\n', &psh->errout);
		flushout(&psh->errout);
	}

	/* Now locate the command. */
	if (argc == 0) {
		cmdentry.cmdtype = CMDSPLBLTIN;
		cmdentry.u.bltin = bltincmd;
	} else {
		static const char PATH[] = "PATH=";
		int cmd_flags = DO_ERR;

		/*
		 * Modify the command lookup path, if a PATH= assignment
		 * is present
		 */
		for (sp = varlist.list; sp; sp = sp->next)
			if (strncmp(sp->text, PATH, sizeof(PATH) - 1) == 0)
				path = sp->text + sizeof(PATH) - 1;

		do {
			int argsused, use_syspath;
			find_command(psh, argv[0], &cmdentry, cmd_flags, path);
			if (cmdentry.cmdtype == CMDUNKNOWN) {
				psh->exitstatus = 127;
				flushout(&psh->errout);
				goto out;
			}

			/* implement the 'command' builtin here */
			if (cmdentry.cmdtype != CMDBUILTIN ||
			    cmdentry.u.bltin != bltincmd)
				break;
			cmd_flags |= DO_NOFUNC;
			argsused = parse_command_args(psh, argc, argv, &use_syspath);
			if (argsused == 0) {
				/* use 'type' builting to display info */
				cmdentry.u.bltin = typecmd;
				break;
			}
			argc -= argsused;
			argv += argsused;
			if (use_syspath)
				path = syspath(psh) + 5;
		} while (argc != 0);
		if (cmdentry.cmdtype == CMDSPLBLTIN && cmd_flags & DO_NOFUNC)
			/* posix mandates that 'command <splbltin>' act as if
			   <splbltin> was a normal builtin */
			cmdentry.cmdtype = CMDBUILTIN;
	}

	/* Fork off a child process if necessary. */
	if (cmd->ncmd.backgnd
	 || (cmdentry.cmdtype == CMDNORMAL && (flags & EV_EXIT) == 0)
	 || ((flags & EV_BACKCMD) != 0
	    && ((cmdentry.cmdtype != CMDBUILTIN && cmdentry.cmdtype != CMDSPLBLTIN)
		 || cmdentry.u.bltin == dotcmd
		 || cmdentry.u.bltin == evalcmd))) {
		INTOFF;
		jp = makejob(psh, cmd, 1);
		mode = cmd->ncmd.backgnd;
		if (flags & EV_BACKCMD) {
			mode = FORK_NOJOB;
			if (sh_pipe(psh, pip) < 0)
				error(psh, "Pipe call failed");
		}
#ifdef DO_SHAREDVFORK
		/* It is essential that if DO_SHAREDVFORK is defined that the
		 * child's address space is actually shared with the parent as
		 * we rely on this.
		 */
		if (cmdentry.cmdtype == CMDNORMAL) {
			pid_t	pid;

			savelocalvars = psh->localvars;
			psh->localvars = NULL;
			psh->vforked = 1;
			switch (pid = vfork()) {
			case -1:
				TRACE((psh, "Vfork failed, errno=%d\n", errno));
				INTON;
				error(psh, "Cannot vfork");
				break;
			case 0:
				/* Make sure that exceptions only unwind to
				 * after the vfork(2)
				 */
				if (setjmp(jmploc.loc)) {
					if (psh->exception == EXSHELLPROC) {
						/* We can't progress with the vfork,
						 * so, set vforked = 2 so the parent
						 * knows, and _exit();
						 */
						psh->vforked = 2;
						sh__exit(psh, 0);
					} else {
						sh__exit(psh, psh->exerrno);
					}
				}
				savehandler = psh->handler;
				psh->handler = &jmploc;
				listmklocal(psh, varlist.list, VEXPORT | VNOFUNC);
				forkchild(psh, jp, cmd, mode, psh->vforked);
				break;
			default:
				psh->handler = savehandler;	/* restore from vfork(2) */
				poplocalvars(psh);
				psh->localvars = savelocalvars;
				if (psh->vforked == 2) {
					psh->vforked = 0;

					(void)sh_waitpid(psh, pid, NULL, 0);
					/* We need to progress in a normal fork fashion */
					goto normal_fork;
				}
				psh->vforked = 0;
				forkparent(psh, jp, cmd, mode, pid);
				goto parent;
			}
		} else {
normal_fork:
#endif
			if (forkshell(psh, jp, cmd, mode) != 0)
				goto parent;	/* at end of routine */
			FORCEINTON;
#ifdef DO_SHAREDVFORK
		}
#endif
		if (flags & EV_BACKCMD) {
			if (!psh->vforked) {
				FORCEINTON;
			}
			shfile_close(&psh->fdtab, pip[0]);
			if (pip[1] != 1) {
				movefd(psh, pip[1], 1);
			}
		}
		flags |= EV_EXIT;
	}

	/* This is the child process if a fork occurred. */
	/* Execute the command. */
	switch (cmdentry.cmdtype) {
	case CMDFUNCTION:
#ifdef DEBUG
		trputs(psh, "Shell function:  ");  trargs(psh, argv);
#endif
		redirect(psh, cmd->ncmd.redirect, REDIR_PUSH);
		saveparam = psh->shellparam;
		psh->shellparam.malloc = 0;
		psh->shellparam.reset = 1;
		psh->shellparam.nparam = argc - 1;
		psh->shellparam.p = argv + 1;
		psh->shellparam.optnext = NULL;
		INTOFF;
		savelocalvars = psh->localvars;
		psh->localvars = NULL;
		INTON;
		if (setjmp(jmploc.loc)) {
			if (psh->exception == EXSHELLPROC) {
				freeparam(psh, (volatile struct shparam *)
				    &saveparam);
			} else {
				freeparam(psh, &psh->shellparam);
				psh->shellparam = saveparam;
			}
			poplocalvars(psh);
			psh->localvars = savelocalvars;
			psh->handler = savehandler;
			longjmp(psh->handler->loc, 1);
		}
		savehandler = psh->handler;
		psh->handler = &jmploc;
		listmklocal(psh, varlist.list, 0);
		/* stop shell blowing its stack */
		if (++psh->funcnest > 1000)
			error(psh, "too many nested function calls");
		evaltree(psh, cmdentry.u.func, flags & EV_TESTED);
		psh->funcnest--;
		INTOFF;
		poplocalvars(psh);
		psh->localvars = savelocalvars;
		freeparam(psh, &psh->shellparam);
		psh->shellparam = saveparam;
		psh->handler = savehandler;
		popredir(psh);
		INTON;
		if (psh->evalskip == SKIPFUNC) {
			psh->evalskip = 0;
			psh->skipcount = 0;
		}
		if (flags & EV_EXIT)
			exitshell(psh, psh->exitstatus);
		break;

	case CMDBUILTIN:
	case CMDSPLBLTIN:
#ifdef DEBUG
		trputs(psh, "builtin command:  ");  trargs(psh, argv);
#endif
		mode = (cmdentry.u.bltin == execcmd) ? 0 : REDIR_PUSH;
		if (flags == EV_BACKCMD) {
			psh->memout.nleft = 0;
			psh->memout.nextc = psh->memout.buf;
			psh->memout.bufsize = 64;
			mode |= REDIR_BACKQ;
		}
		e = -1;
		savehandler = psh->handler;
		savecmdname = psh->commandname;
		psh->handler = &jmploc;
		if (!setjmp(jmploc.loc)) {
			/* We need to ensure the command hash table isn't
			 * corruped by temporary PATH assignments.
			 * However we must ensure the 'local' command works!
			 */
			if (path != pathval(psh) && (cmdentry.u.bltin == hashcmd ||
			    cmdentry.u.bltin == typecmd)) {
				savelocalvars = psh->localvars;
				psh->localvars = 0;
				mklocal(psh, path - 5 /* PATH= */, 0);
				temp_path = 1;
			} else
				temp_path = 0;
			redirect(psh, cmd->ncmd.redirect, mode);

			/* exec is a special builtin, but needs this list... */
			psh->cmdenviron = varlist.list;
			/* we must check 'readonly' flag for all builtins */
			listsetvar(psh, varlist.list,
				cmdentry.cmdtype == CMDSPLBLTIN ? 0 : VNOSET);
			psh->commandname = argv[0];
			/* initialize nextopt */
			psh->argptr = argv + 1;
			psh->optptr = NULL;
			/* and getopt */
#if 0 /** @todo fix getop usage! */
#if defined(__FreeBSD__) || defined(__EMX__) || defined(__APPLE__)
			optreset = 1;
			optind = 1;
#else
			optind = 0; /* init */
#endif
#endif

			psh->exitstatus = cmdentry.u.bltin(psh, argc, argv);
		} else {
			e = psh->exception;
			psh->exitstatus = e == EXINT ? SIGINT + 128 :
					e == EXEXEC ? psh->exerrno : 2;
		}
		psh->handler = savehandler;
		output_flushall(psh);
		psh->out1 = &psh->output;
		psh->out2 = &psh->errout;
		freestdout(psh);
		if (temp_path) {
			poplocalvars(psh);
			psh->localvars = savelocalvars;
		}
		psh->cmdenviron = NULL;
		if (e != EXSHELLPROC) {
			psh->commandname = savecmdname;
			if (flags & EV_EXIT)
				exitshell(psh, psh->exitstatus);
		}
		if (e != -1) {
			if ((e != EXERROR && e != EXEXEC)
			    || cmdentry.cmdtype == CMDSPLBLTIN)
				exraise(psh, e);
			FORCEINTON;
		}
		if (cmdentry.u.bltin != execcmd)
			popredir(psh);
		if (flags == EV_BACKCMD) {
			backcmd->buf = psh->memout.buf;
			backcmd->nleft = (int)(psh->memout.nextc - psh->memout.buf);
			psh->memout.buf = NULL;
		}
		break;

	default:
#ifdef DEBUG
		trputs(psh, "normal command:  ");  trargs(psh, argv);
#endif
		clearredir(psh, psh->vforked);
		redirect(psh, cmd->ncmd.redirect, psh->vforked ? REDIR_VFORK : 0);
		if (!psh->vforked)
			for (sp = varlist.list ; sp ; sp = sp->next)
				setvareq(psh, sp->text, VEXPORT|VSTACK);
		envp = environment(psh);
		shellexec(psh, argv, envp, path, cmdentry.u.index, psh->vforked);
		break;
	}
	goto out;

parent:	/* parent process gets here (if we forked) */
	if (mode == FORK_FG) {	/* argument to fork */
		psh->exitstatus = waitforjob(psh, jp);
	} else if (mode == FORK_NOJOB) {
		backcmd->fd = pip[0];
		shfile_close(&psh->fdtab, pip[1]);
		backcmd->jp = jp;
	}
	FORCEINTON;

out:
	if (lastarg)
		/* dsl: I think this is intended to be used to support
		 * '_' in 'vi' command mode during line editing...
		 * However I implemented that within libedit itself.
		 */
		setvar(psh, "_", lastarg, 0);
	popstackmark(psh, &smark);

	if (eflag(psh) && psh->exitstatus && !(flags & EV_TESTED))
		exitshell(psh, psh->exitstatus);
}