const char* FAST_FUNC
endofname(const char *name)
{
if (!is_name(*name))
return name;
while (*++name) {
if (!is_in_name(*name))
break;
}
return name;
}
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;
}
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);
}
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);
}
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;
}
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);
}
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) "ef;
(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 */
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);
}
