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-rw-r--r--hush.c92
-rw-r--r--shell/hush.c92
2 files changed, 122 insertions, 62 deletions
diff --git a/hush.c b/hush.c
index a1e65b24e..fc45bb270 100644
--- a/hush.c
+++ b/hush.c
@@ -365,6 +365,7 @@ static int setup_redirects(struct child_prog *prog, int squirrel[]);
static int pipe_wait(struct pipe *pi);
static int run_list_real(struct pipe *pi);
static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
+int controlling_tty(int check_pgrp);
static int run_pipe_real(struct pipe *pi);
/* extended glob support: */
static int globhack(const char *src, int flags, glob_t *pglob);
@@ -576,7 +577,7 @@ static int builtin_fg_bg(struct child_prog *child)
signal(SIGTTOU, SIG_IGN);
/* suppress messages when run from /linuxrc mag@sysgo.de */
if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-1");
signal(SIGTTOU, SIG_DFL);
job_list->fg = pi;
}
@@ -1059,13 +1060,14 @@ static int pipe_wait(struct pipe *pi)
return rcode;
}
-/* very simple version for testing */
+/* never returns */
static void pseudo_exec(struct child_prog *child)
{
int i, rcode;
struct built_in_command *x;
if (child->argv) {
for (i=0; is_assignment(child->argv[i]); i++) {
+ debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
putenv(strdup(child->argv[i]));
}
child->argv+=i; /* XXX this hack isn't so horrible, since we are about
@@ -1125,7 +1127,7 @@ static void pseudo_exec(struct child_prog *child)
#endif
debug_printf("exec of %s\n",child->argv[0]);
execvp(child->argv[0],child->argv);
- perror("execvp");
+ perror_msg("couldn't exec: %s",child->argv[0]);
exit(1);
} else if (child->group) {
debug_printf("runtime nesting to group\n");
@@ -1224,7 +1226,7 @@ static void free_pipe(struct pipe *pi)
have, figure out why and see if a job has completed */
static void checkjobs()
{
- int status;
+ int status, ctty;
int prognum = 0;
struct pipe *pi;
pid_t childpid;
@@ -1264,8 +1266,31 @@ static void checkjobs()
perror_msg("waitpid");
/* move the shell to the foreground */
- if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ if (interactive && (ctty=controlling_tty(0))!=-1) {
+ if (tcsetpgrp(ctty, getpgrp()))
+ perror_msg("tcsetpgrp-2");
+ }
+}
+
+/* Figure out our controlling tty, checking in order stderr,
+ * stdin, and stdout. If check_pgrp is set, also check that
+ * we belong to the foreground process group associated with
+ * that tty. The value of ctty is needed in order to call
+ * tcsetpgrp(ctty, ...); */
+int controlling_tty(int check_pgrp)
+{
+ pid_t curpgrp;
+ int ctty;
+
+ if ((curpgrp = tcgetpgrp(ctty = 2)) < 0
+ && (curpgrp = tcgetpgrp(ctty = 0)) < 0
+ && (curpgrp = tcgetpgrp(ctty = 1)) < 0)
+ return errno = ENOTTY, -1;
+
+ if (check_pgrp && curpgrp != getpgrp())
+ return errno = EPERM, -1;
+
+ return ctty;
}
/* run_pipe_real() starts all the jobs, but doesn't wait for anything
@@ -1295,17 +1320,11 @@ static int run_pipe_real(struct pipe *pi)
ctty = -1;
nextin = 0;
- pi->pgrp = 0;
+ pi->pgrp = -1;
/* Check if we are supposed to run in the foreground */
if (interactive && pi->followup!=PIPE_BG) {
- if ((pi->pgrp = tcgetpgrp(ctty = 2)) < 0
- && (pi->pgrp = tcgetpgrp(ctty = 0)) < 0
- && (pi->pgrp = tcgetpgrp(ctty = 1)) < 0)
- return errno = ENOTTY, -1;
-
- if (pi->pgrp < 0 && pi->pgrp != getpgrp())
- return errno = EPERM, -1;
+ if ((ctty = controlling_tty(pi->pgrp<0)) < 0) return -1;
}
/* Check if this is a simple builtin (not part of a pipe).
@@ -1395,11 +1414,11 @@ static int run_pipe_real(struct pipe *pi)
* and the pipe fd is available for dup'ing. */
setup_redirects(child,NULL);
- if (pi->followup!=PIPE_BG) {
+ if (interactive && pi->followup!=PIPE_BG) {
/* If we (the child) win the race, put ourselves in the process
* group whose leader is the first process in this pipe. */
if (pi->pgrp < 0) {
- pi->pgrp = child->pid;
+ pi->pgrp = getpid();
}
if (setpgid(0, pi->pgrp) == 0) {
signal(SIGTTOU, SIG_IGN);
@@ -1461,13 +1480,15 @@ static int run_list_real(struct pipe *pi)
if (interactive) {
/* move the new process group into the foreground */
/* suppress messages when run from /linuxrc mag@sysgo.de */
+ /* XXX probably this "0" should come from controlling_tty() */
if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-3");
rcode = pipe_wait(pi);
if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-4");
} else {
rcode = pipe_wait(pi);
+ debug_printf("pipe_wait returned %d\n",rcode);
}
}
last_return_code=rcode;
@@ -2484,6 +2505,25 @@ static int parse_file_outer(FILE *f)
return rcode;
}
+
+/* I think Erik wrote this. It looks imperfect at best */
+void grab_tty_control(void)
+{
+ pid_t initialpgrp;
+ do {
+ initialpgrp = tcgetpgrp(fileno(stderr));
+ if (initialpgrp < 0) {
+ error_msg("sh: can't access tty; job control disabled\n");
+ }
+ if (initialpgrp == -1)
+ initialpgrp = getpgrp();
+ else if (initialpgrp != getpgrp()) {
+ killpg(initialpgrp, SIGTTIN);
+ continue;
+ }
+ } while (0);
+}
+
int shell_main(int argc, char **argv)
{
int opt;
@@ -2507,19 +2547,6 @@ int shell_main(int argc, char **argv)
/* If we get started under a job aware app (like bash
* for example), make sure we are now in charge so we
* don't fight over who gets the foreground */
- do {
- pid_t initialpgrp;
- initialpgrp = tcgetpgrp(fileno(stderr));
- if (initialpgrp < 0) {
- error_msg_and_die("sh: can't access tty; job control disabled\n");
- }
- if (initialpgrp == -1)
- initialpgrp = getpgrp();
- else if (initialpgrp != getpgrp()) {
- killpg(initialpgrp, SIGTTIN);
- continue;
- }
- } while (0);
/* don't pay any attention to this signal; it just confuses
things and isn't really meant for shells anyway */
signal(SIGTTOU, SIG_IGN);
@@ -2588,6 +2615,9 @@ int shell_main(int argc, char **argv)
if (interactive) {
/* Looks like they want an interactive shell */
fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ grab_tty_control();
+ }
+ if (argv[optind]==NULL) {
opt=parse_file_outer(stdin);
goto final_return;
}
diff --git a/shell/hush.c b/shell/hush.c
index a1e65b24e..fc45bb270 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -365,6 +365,7 @@ static int setup_redirects(struct child_prog *prog, int squirrel[]);
static int pipe_wait(struct pipe *pi);
static int run_list_real(struct pipe *pi);
static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
+int controlling_tty(int check_pgrp);
static int run_pipe_real(struct pipe *pi);
/* extended glob support: */
static int globhack(const char *src, int flags, glob_t *pglob);
@@ -576,7 +577,7 @@ static int builtin_fg_bg(struct child_prog *child)
signal(SIGTTOU, SIG_IGN);
/* suppress messages when run from /linuxrc mag@sysgo.de */
if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-1");
signal(SIGTTOU, SIG_DFL);
job_list->fg = pi;
}
@@ -1059,13 +1060,14 @@ static int pipe_wait(struct pipe *pi)
return rcode;
}
-/* very simple version for testing */
+/* never returns */
static void pseudo_exec(struct child_prog *child)
{
int i, rcode;
struct built_in_command *x;
if (child->argv) {
for (i=0; is_assignment(child->argv[i]); i++) {
+ debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
putenv(strdup(child->argv[i]));
}
child->argv+=i; /* XXX this hack isn't so horrible, since we are about
@@ -1125,7 +1127,7 @@ static void pseudo_exec(struct child_prog *child)
#endif
debug_printf("exec of %s\n",child->argv[0]);
execvp(child->argv[0],child->argv);
- perror("execvp");
+ perror_msg("couldn't exec: %s",child->argv[0]);
exit(1);
} else if (child->group) {
debug_printf("runtime nesting to group\n");
@@ -1224,7 +1226,7 @@ static void free_pipe(struct pipe *pi)
have, figure out why and see if a job has completed */
static void checkjobs()
{
- int status;
+ int status, ctty;
int prognum = 0;
struct pipe *pi;
pid_t childpid;
@@ -1264,8 +1266,31 @@ static void checkjobs()
perror_msg("waitpid");
/* move the shell to the foreground */
- if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ if (interactive && (ctty=controlling_tty(0))!=-1) {
+ if (tcsetpgrp(ctty, getpgrp()))
+ perror_msg("tcsetpgrp-2");
+ }
+}
+
+/* Figure out our controlling tty, checking in order stderr,
+ * stdin, and stdout. If check_pgrp is set, also check that
+ * we belong to the foreground process group associated with
+ * that tty. The value of ctty is needed in order to call
+ * tcsetpgrp(ctty, ...); */
+int controlling_tty(int check_pgrp)
+{
+ pid_t curpgrp;
+ int ctty;
+
+ if ((curpgrp = tcgetpgrp(ctty = 2)) < 0
+ && (curpgrp = tcgetpgrp(ctty = 0)) < 0
+ && (curpgrp = tcgetpgrp(ctty = 1)) < 0)
+ return errno = ENOTTY, -1;
+
+ if (check_pgrp && curpgrp != getpgrp())
+ return errno = EPERM, -1;
+
+ return ctty;
}
/* run_pipe_real() starts all the jobs, but doesn't wait for anything
@@ -1295,17 +1320,11 @@ static int run_pipe_real(struct pipe *pi)
ctty = -1;
nextin = 0;
- pi->pgrp = 0;
+ pi->pgrp = -1;
/* Check if we are supposed to run in the foreground */
if (interactive && pi->followup!=PIPE_BG) {
- if ((pi->pgrp = tcgetpgrp(ctty = 2)) < 0
- && (pi->pgrp = tcgetpgrp(ctty = 0)) < 0
- && (pi->pgrp = tcgetpgrp(ctty = 1)) < 0)
- return errno = ENOTTY, -1;
-
- if (pi->pgrp < 0 && pi->pgrp != getpgrp())
- return errno = EPERM, -1;
+ if ((ctty = controlling_tty(pi->pgrp<0)) < 0) return -1;
}
/* Check if this is a simple builtin (not part of a pipe).
@@ -1395,11 +1414,11 @@ static int run_pipe_real(struct pipe *pi)
* and the pipe fd is available for dup'ing. */
setup_redirects(child,NULL);
- if (pi->followup!=PIPE_BG) {
+ if (interactive && pi->followup!=PIPE_BG) {
/* If we (the child) win the race, put ourselves in the process
* group whose leader is the first process in this pipe. */
if (pi->pgrp < 0) {
- pi->pgrp = child->pid;
+ pi->pgrp = getpid();
}
if (setpgid(0, pi->pgrp) == 0) {
signal(SIGTTOU, SIG_IGN);
@@ -1461,13 +1480,15 @@ static int run_list_real(struct pipe *pi)
if (interactive) {
/* move the new process group into the foreground */
/* suppress messages when run from /linuxrc mag@sysgo.de */
+ /* XXX probably this "0" should come from controlling_tty() */
if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-3");
rcode = pipe_wait(pi);
if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-4");
} else {
rcode = pipe_wait(pi);
+ debug_printf("pipe_wait returned %d\n",rcode);
}
}
last_return_code=rcode;
@@ -2484,6 +2505,25 @@ static int parse_file_outer(FILE *f)
return rcode;
}
+
+/* I think Erik wrote this. It looks imperfect at best */
+void grab_tty_control(void)
+{
+ pid_t initialpgrp;
+ do {
+ initialpgrp = tcgetpgrp(fileno(stderr));
+ if (initialpgrp < 0) {
+ error_msg("sh: can't access tty; job control disabled\n");
+ }
+ if (initialpgrp == -1)
+ initialpgrp = getpgrp();
+ else if (initialpgrp != getpgrp()) {
+ killpg(initialpgrp, SIGTTIN);
+ continue;
+ }
+ } while (0);
+}
+
int shell_main(int argc, char **argv)
{
int opt;
@@ -2507,19 +2547,6 @@ int shell_main(int argc, char **argv)
/* If we get started under a job aware app (like bash
* for example), make sure we are now in charge so we
* don't fight over who gets the foreground */
- do {
- pid_t initialpgrp;
- initialpgrp = tcgetpgrp(fileno(stderr));
- if (initialpgrp < 0) {
- error_msg_and_die("sh: can't access tty; job control disabled\n");
- }
- if (initialpgrp == -1)
- initialpgrp = getpgrp();
- else if (initialpgrp != getpgrp()) {
- killpg(initialpgrp, SIGTTIN);
- continue;
- }
- } while (0);
/* don't pay any attention to this signal; it just confuses
things and isn't really meant for shells anyway */
signal(SIGTTOU, SIG_IGN);
@@ -2588,6 +2615,9 @@ int shell_main(int argc, char **argv)
if (interactive) {
/* Looks like they want an interactive shell */
fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ grab_tty_control();
+ }
+ if (argv[optind]==NULL) {
opt=parse_file_outer(stdin);
goto final_return;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 03:36:54 +0000