/*
* NAME
* sh6 - shell (command interpreter)
*
* SYNOPSIS
* sh6 [- | -c [string] | -t | file [arg1 ...]]
*
* DESCRIPTION
* See the sh6(1) manual page for full details.
*/
int
main(int argc, char **argv)
{
bool dosigs = false;
sh_init(argv[0]);
if (argv[0] == NULL || *argv[0] == EOS)
err(SH_ERR, FMT1S, ERR_ALINVAL);
if (fd_isdir(FD0))
goto done;
if (argc > 1) {
name = argv[1];
dolv = &argv[1];
dolc = argc - 1;
if (*argv[1] == HYPHEN) {
dosigs = true;
if (argv[1][1] == 'c' && argc > 2) {
dolv += 1;
dolc -= 1;
argv2p = argv[2];
} else if (argv[1][1] == 't')
one_line_flag = 2;
} else {
(void)close(FD0);
if (open(argv[1], O_RDONLY) != FD0)
err(SH_ERR, FMT2S, argv[1], ERR_OPEN);
if (fd_isdir(FD0))
goto done;
}
} else {
dosigs = true;
if (isatty(FD0) != 0 && isatty(FD2) != 0)
prompt = (geteuid() != 0) ? "% " : "# ";
}
if (dosigs) {
if (sasignal(SIGINT, SIG_IGN) == SIG_DFL)
sig_child |= S_SIGINT;
if (sasignal(SIGQUIT, SIG_IGN) == SIG_DFL)
sig_child |= S_SIGQUIT;
if (prompt != NULL)
if (sasignal(SIGTERM, SIG_IGN) == SIG_DFL)
sig_child |= S_SIGTERM;
}
fd_free();
sh_magic();
loop:
if (prompt != NULL)
fd_print(FD2, "%s", prompt);
rpx_line();
goto loop;
done:
return status;
}
/*
* NAME
* if - conditional command
*
* SYNOPSIS
* if [expression [command [arg ...]]]
*
* DESCRIPTION
* See the if(1) manual page for full details.
*/
int
main(int argc, char **argv)
{
bool re; /* return value of expr() */
setmyerrexit(&ut_errexit);
setmyname(argv[0]);
setmypid(getpid());
ifeuid = geteuid();
/*
* Set-ID execution is not supported.
*/
if (ifeuid != getuid() || getegid() != getgid())
err(FC_ERR, FMT2S, getmyname(), ERR_SETID);
(void)sasignal(SIGCHLD, SIG_DFL);
if (argc > 1) {
ac = argc;
av = argv;
ap = 1;
re = expr();
if (re && ap < ac)
doex(!FORKED);
} else
re = false;
return re ? SH_TRUE : SH_FALSE;
}
/*
* Initialize the shell.
*/
static void
sh_init(const char *av0p)
{
struct stat sb;
int i;
setmyerrexit(&sh_errexit);
setmyname(av0p);
setmypid(getpid());
/*
* Set-ID execution is not supported.
*/
if (geteuid() != getuid() || getegid() != getgid())
err(SH_ERR, FMT1S, ERR_SETID);
/*
* Save the process ID of the shell as a 5-digit ASCII
* string (apid). Each occurrence of `$$' in a command
* line is substituted w/ the value of apid.
*/
i = snprintf(apid, sizeof(apid), "%05u", (unsigned)getmypid());
if (i < 0 || i >= (int)sizeof(apid))
*apid = EOS;
/*
* Fail if any of the descriptors 0, 1, or 2 is not open.
*/
for (i = 0; i < 3; i++)
if (fstat(i, &sb) == -1)
err(SH_ERR, "%u: %s\n", (unsigned)i, strerror(errno));
/*
* Set the SIGCHLD signal to its default action.
* Correct operation of the shell requires that zombies
* be created for its children when they terminate.
*/
(void)sasignal(SIGCHLD, SIG_DFL);
}
/*
* Execute the shell command tree pointed to by t.
*/
static void
execute(struct tnode *t, int *pin, int *pout)
{
struct tnode *t1;
enum tnflags f;
pid_t cpid;
int i, pfd[2];
const char **gav;
const char *cmd, *p;
if (t == NULL)
return;
switch (t->ntype) {
case TLIST:
f = t->nflags & (FFIN | FPIN | FINTR);
if ((t1 = t->nleft) != NULL)
t1->nflags |= f;
execute(t1, NULL, NULL);
if ((t1 = t->nright) != NULL)
t1->nflags |= f;
execute(t1, NULL, NULL);
return;
case TPIPE:
if (pipe(pfd) == -1) {
err(SH_ERR, FMT1S, ERR_PIPE);
if (pin != NULL) {
(void)close(pin[0]);
(void)close(pin[1]);
}
return;
}
f = t->nflags;
if ((t1 = t->nleft) != NULL)
t1->nflags |= FPOUT | (f & (FFIN|FPIN|FINTR|FPRS));
execute(t1, pin, pfd);
if ((t1 = t->nright) != NULL)
t1->nflags |= FPIN | (f & (FAND|FPOUT|FINTR|FPRS));
execute(t1, pfd, pout);
(void)close(pfd[0]);
(void)close(pfd[1]);
return;
case TCOMMAND:
if (t->nav == NULL || t->nav[0] == NULL) {
/* should never (but can) be true */
err(SH_ERR, FMT1S, "execute: Invalid command");
return;
}
cmd = t->nav[0];
if (EQUAL(cmd, ":")) {
status = SH_TRUE;
return;
}
if (EQUAL(cmd, "chdir")) {
ascan(t->nav[1], &trim);
if (t->nav[1] == NULL)
err(SH_ERR, FMT2S, cmd, ERR_ARGCOUNT);
else if (chdir(t->nav[1]) == -1)
err(SH_ERR, FMT2S, cmd, ERR_BADDIR);
else
status = SH_TRUE;
return;
}
if (EQUAL(cmd, "exit")) {
if (prompt == NULL) {
(void)lseek(FD0, (off_t)0, SEEK_END);
EXIT(status);
}
return;
}
if (EQUAL(cmd, "login") || EQUAL(cmd, "newgrp")) {
if (prompt != NULL) {
p = (*cmd == 'l') ? PATH_LOGIN : PATH_NEWGRP;
vscan(t->nav, &trim);
(void)sasignal(SIGINT, SIG_DFL);
(void)sasignal(SIGQUIT, SIG_DFL);
(void)pexec(p, (char *const *)t->nav);
(void)sasignal(SIGINT, SIG_IGN);
(void)sasignal(SIGQUIT, SIG_IGN);
}
err(SH_ERR, FMT2S, cmd, ERR_EXEC);
return;
}
if (EQUAL(cmd, "shift")) {
if (dolc > 1) {
dolv = &dolv[1];
dolc--;
status = SH_TRUE;
return;
}
err(SH_ERR, FMT2S, cmd, ERR_NOARGS);
return;
}
if (EQUAL(cmd, "wait")) {
pwait(-1);
return;
}
/*FALLTHROUGH*/
case TSUBSHELL:
f = t->nflags;
if ((cpid = ((f & FNOFORK) != 0) ? 0 : fork()) == -1) {
err(SH_ERR, FMT1S, ERR_FORK);
return;
}
/**** Parent! ****/
if (cpid != 0) {
if (pin != NULL && (f & FPIN) != 0) {
(void)close(pin[0]);
(void)close(pin[1]);
}
if ((f & FPRS) != 0)
fd_print(FD2, "%u\n", (unsigned)cpid);
if ((f & FAND) != 0)
return;
if ((f & FPOUT) == 0)
pwait(cpid);
return;
}
/**** Child! ****/
/*
* Redirect (read) input from pipe.
*/
if (pin != NULL && (f & FPIN) != 0) {
if (dup2(pin[0], FD0) == -1)
err(FC_ERR, FMT1S, strerror(errno));
(void)close(pin[0]);
(void)close(pin[1]);
}
/*
* Redirect (write) output to pipe.
*/
if (pout != NULL && (f & FPOUT) != 0) {
if (dup2(pout[1], FD1) == -1)
err(FC_ERR, FMT1S, strerror(errno));
(void)close(pout[0]);
(void)close(pout[1]);
}
/*
* Redirect (read) input from file.
*/
if (t->nfin != NULL && (f & FPIN) == 0) {
f |= FFIN;
ascan(t->nfin, &trim);
if ((i = open(t->nfin, O_RDONLY)) == -1)
err(FC_ERR, FMT2S, t->nfin, ERR_OPEN);
if (dup2(i, FD0) == -1)
err(FC_ERR, FMT1S, strerror(errno));
(void)close(i);
}
/*
* Redirect (write) output to file.
*/
if (t->nfout != NULL && (f & FPOUT) == 0) {
if ((f & FCAT) != 0)
i = O_WRONLY | O_APPEND | O_CREAT;
else
i = O_WRONLY | O_TRUNC | O_CREAT;
ascan(t->nfout, &trim);
if ((i = open(t->nfout, i, 0666)) == -1)
err(FC_ERR, FMT2S, t->nfout, ERR_CREATE);
if (dup2(i, FD1) == -1)
err(FC_ERR, FMT1S, strerror(errno));
(void)close(i);
}
/*
* Set the action for the SIGINT and SIGQUIT signals, and
* redirect input for `&' commands from `/dev/null' if needed.
*/
if ((f & FINTR) != 0) {
(void)sasignal(SIGINT, SIG_IGN);
(void)sasignal(SIGQUIT, SIG_IGN);
if (t->nfin == NULL && (f & (FFIN|FPIN|FPRS)) == FPRS) {
(void)close(FD0);
if (open("/dev/null", O_RDONLY) != FD0)
err(FC_ERR,FMT2S,"/dev/null",ERR_OPEN);
}
} else {
if ((sig_child & S_SIGINT) != 0)
(void)sasignal(SIGINT, SIG_DFL);
if ((sig_child & S_SIGQUIT) != 0)
(void)sasignal(SIGQUIT, SIG_DFL);
}
/* Set the SIGTERM signal to its default action if needed. */
if ((sig_child & S_SIGTERM) != 0)
(void)sasignal(SIGTERM, SIG_DFL);
if (t->ntype == TSUBSHELL) {
if ((t1 = t->nsub) != NULL)
t1->nflags |= (f & (FFIN | FPIN | FINTR));
execute(t1, NULL, NULL);
_exit(status);
}
glob_flag = false;
vscan(t->nav, &tglob);
if (glob_flag) {
for (i = 0; t->nav[i] != NULL; i++)
; /* nothing */
#ifdef DEBUG
#ifdef DEBUG_GLOB
fd_print(FD2, "execute: i == %2d;\n", i);
fd_print(FD2, " : (i + 2) == %2d;\n", (i + 2));
fd_print(FD2, " : (i + 1) == %2d;\n", (i + 1));
#endif
#endif
gav = xmalloc((i + 2) * sizeof(char *));
gav[0] = "glob6";
cmd = gav[0];
(void)memcpy(&gav[1], t->nav, (i + 1) * sizeof(char *));
#ifdef DEBUG
#ifdef DEBUG_GLOB
for (i = 0; gav[i] != NULL; i++)
fd_print(FD2, " : gav[%2d] == %s;\n",
i, gav[i]);
fd_print(FD2, " : gav[%2d] == NULL;\n", i);
#endif
#endif
(void)err_pexec(cmd, (char *const *)gav);
} else {
vscan(t->nav, &trim);
cmd = t->nav[0];
(void)err_pexec(cmd, (char *const *)t->nav);
}
/*NOTREACHED*/
}
}
