yash: ジョブ制御有効時にシェルの pgid を変更するのをやめた

	yash: -initial_pgid, set_own_pgid, reset_own_pgid, forget_initial_pgid,
	yash: -finalize_shell, reinitialize_shell
yash: シェル起動時にシェル自身がフォアグラウンドにいるか確認するように
	job: +ensure_foreground


git-svn-id: svn+ssh://svn.sourceforge.jp/svnroot/yash/yash/trunk@1324 048f04df-13f5-43d7-8114-9f9ceecaec24

Author: magicant

exec.c

@@ -813,8 +813,7 @@ pid_t fork_and_reset(pid_t pgid, bool fg, sigtype_T sigtype)
     if (sigblock) {
 	sigfillset(&all);
 	sigemptyset(&savemask);
-	if (sigprocmask(SIG_BLOCK, &all, &savemask) < 0)
-	    xerror(errno, "sigprocmask"), sigblock = false;
+	sigprocmask(SIG_BLOCK, &all, &savemask);
     }
 
     pid_t cpid = fork();
@@ -840,7 +839,6 @@ pid_t fork_and_reset(pid_t pgid, bool fg, sigtype_T sigtype)
 		put_foreground(pgid);
 	    }
 	}
-	forget_initial_pgid();
 	neglect_all_jobs();
 	restore_job_signals();
 	restore_interactive_signals();
@@ -859,8 +857,7 @@ pid_t fork_and_reset(pid_t pgid, bool fg, sigtype_T sigtype)
 		ignore_sigtstp();
     }
     if (sigblock)
-	if (sigprocmask(SIG_SETMASK, &savemask, NULL) < 0)
-	    xerror(errno, "sigprocmask");
+	sigprocmask(SIG_SETMASK, &savemask, NULL);
     return cpid;
 }
 
@@ -1777,7 +1774,6 @@ int exec_builtin_2(int argc, void **argv, const wchar_t *as, bool clear)
 	}
     }
 
-    finalize_shell();
     restore_all_signals();
     xexecve(commandpath, args, envs ? envs : environ);
     if (errno != ENOEXEC) {
@@ -1795,7 +1791,6 @@ int exec_builtin_2(int argc, void **argv, const wchar_t *as, bool clear)
 	exit(Exit_NOEXEC);
     init_signal();
     set_signals();
-    reinitialize_shell();
     err = Exit_NOEXEC;
 
     recfree((void **) envs, free);

job.c

@@ -450,7 +450,6 @@ int send_signal_to_job(int signum, const wchar_t *jobname)
  * true. */
 void put_foreground(pid_t pgrp)
 {
-    bool saveok;
     sigset_t blockss, savess;
 
     assert(doing_job_control_now);
@@ -459,12 +458,43 @@ void put_foreground(pid_t pgrp)
     sigemptyset(&blockss);
     sigaddset(&blockss, SIGTTOU);
     sigemptyset(&savess);
-    saveok = sigprocmask(SIG_BLOCK, &blockss, &savess) >= 0;
+    sigprocmask(SIG_BLOCK, &blockss, &savess);
 
     tcsetpgrp(ttyfd, pgrp);
 
-    if (saveok)
-	sigprocmask(SIG_SETMASK, &savess, NULL);
+    sigprocmask(SIG_SETMASK, &savess, NULL);
+}
+
+/* Ensures the current shell process is in the foreground.
+ * The shell process is stopped by SIGTTOU until it is put in the foreground.
+ * This function requires `doing_job_control_now' to be true. */
+void ensure_foreground(void)
+{
+    /* This function calls `tcsetpgrp' with the default SIGTTOU handler. If the
+     * shell is in the background, it will receive SIGTTOU and is stopped until
+     * continued in the foreground. */
+
+    struct sigaction dflsa, savesa;
+    sigset_t blockss, savess;
+
+    assert(doing_job_control_now);
+    assert(shell_pgid > 0);
+
+    dflsa.sa_handler = SIG_DFL;
+    dflsa.sa_flags = 0;
+    sigemptyset(&dflsa.sa_mask);
+    sigemptyset(&savesa.sa_mask);
+    sigaction(SIGTTOU, &dflsa, &savesa);
+
+    sigemptyset(&blockss);
+    sigaddset(&blockss, SIGTTOU);
+    sigemptyset(&savess);
+    sigprocmask(SIG_UNBLOCK, &blockss, &savess);
+
+    tcsetpgrp(ttyfd, shell_pgid);
+
+    sigprocmask(SIG_SETMASK, &savess, NULL);
+    sigaction(SIGTTOU, &savesa, NULL);
 }
 
 /* Computes the exit status from the status code returned by `waitpid'. */

job.h

@@ -85,6 +85,7 @@ extern int send_signal_to_job(int signum, const wchar_t *jobname)
     __attribute__((nonnull));
 
 extern void put_foreground(pid_t pgrp);
+extern void ensure_foreground(void);
 
 extern int calc_status_of_job(const job_T *job)
     __attribute__((pure,nonnull));

option.c

@@ -29,6 +29,7 @@
 #endif
 #include "builtin.h"
 #include "exec.h"
+#include "job.h"
 #include "option.h"
 #include "redir.h"
 #include "sig.h"
@@ -325,12 +326,12 @@ void set_monitor_option(void *argp __attribute__((unused)))
 	do_job_control = newvalue;
     } else {
 	if (newvalue != do_job_control) {
-	    reset_own_pgid();
 	    do_job_control = newvalue;
 	    if (newvalue && ttyfd < 0)
 		open_ttyfd();
 	    set_signals();
-	    set_own_pgid();
+	    if (do_job_control)
+		ensure_foreground();
 	}
     }
     /* When `shell_pid' is zero, the shell is under initialization;

tests/builtin.y.out

@@ -92,6 +92,7 @@ type: cd: no such command or function
 ===== suspend =====
 1
 STOP
+TTOU
 2
 end
 ===== exec =====

tests/builtin.y.tst

@@ -107,8 +107,10 @@ PATH= type -B cd 2>&1
 echo ===== suspend =====
 
 set -m
-($INVOKE $TESTEE -imc --norc 'echo 1; suspend; echo 2'; echo end)&
-wait $!
+($INVOKE $TESTEE -imc --norc 'echo 1; suspend; echo 2'; echo end)
+kill -l $?
+bg >/dev/null
+wait %1
 kill -l $?
 fg >/dev/null
 set +m

yash.c

@@ -63,8 +63,7 @@ static bool input_is_interactive_terminal(const parseinfo_T *pinfo)
 
 /* the process ID of the shell */
 pid_t shell_pid;
-/* the initial/current process group ID of the shell */
-static pid_t initial_pgid;
+/* the process group ID of the shell */
 pid_t shell_pgid;
 
 /* an equivalent to the -f flag for "exit" builtin */
@@ -209,7 +208,7 @@ int main(int argc, char **argv)
     /* `shell_pid' must be initialized after the options have been parsed.
      * This is required for the `set_monitor_option' function to work. */
     shell_pid = getpid();
-    initial_pgid = shell_pgid = getpgrp();
+    shell_pgid = getpgrp();
     init_cmdhash();
     init_homedirhash();
     init_variables();
@@ -273,7 +272,8 @@ int main(int argc, char **argv)
     if (is_interactive || do_job_control)
 	open_ttyfd();
     set_signals();
-    set_own_pgid();
+    if (do_job_control)
+	ensure_foreground();
     set_positional_parameters(wargv + xoptind);
     if (getuid() == geteuid() && getgid() == getegid()) {
 	if (!noprofile)
@@ -370,23 +370,9 @@ void exit_shell_with_status(int status)
 	    finalize_history();
 #endif
     }
-    finalize_shell();
     exit(exitstatus);
 }
 
-/* Does what to do before exiting/suspending the shell.
- * The EXIT trap should be executed beforehand if needed. */
-void finalize_shell(void)
-{
-    reset_own_pgid();
-}
-
-/* Cancels `finalize_shell'. */
-void reinitialize_shell(void)
-{
-    set_own_pgid();
-}
-
 /* Prints the help message to stdout */
 void print_help(void)
 {
@@ -456,39 +442,6 @@ void print_version(void)
 }
 
 
-/* If job control is active, sets the process group ID of the shell to its
- * process ID. */
-void set_own_pgid(void)
-{
-    if (doing_job_control_now && initial_pgid > 0 && shell_pgid != shell_pid) {
-	if (setpgid(0, 0) == 0) {
-	    shell_pgid = shell_pid;
-	    put_foreground(shell_pgid);
-	}
-    }
-}
-
-/* If job control is active, resets the process group ID of the shell.
- * The initial process group ID is restored. */
-void reset_own_pgid(void)
-{
-    if (doing_job_control_now && initial_pgid > 0
-	    && initial_pgid != shell_pgid) {
-	if (setpgid(0, initial_pgid) == 0) {
-	    shell_pgid = initial_pgid;
-	    put_foreground(shell_pgid);
-	}
-    }
-}
-
-/* Forgets the value of `initial_pgid' so that `reset_own_pgid' is no longer
- * effective. */
-void forget_initial_pgid(void)
-{
-    initial_pgid = 0;
-}
-
-
 /********** Functions to execute commands **********/
 
 /* Parses a multibyte string and executes the commands.
@@ -746,19 +699,19 @@ int suspend_builtin(int argc, void **argv)
     }
     if (argc != xoptind)
 	goto print_usage;
-    if (!force && is_interactive_now && getsid(0) == initial_pgid) {
+    if (!force && is_interactive_now && getsid(0) == shell_pgid) {
 	xerror(0, Ngt("refusing to suspend because of possible deadlock.\n"
 		    "Use the -f option to suspend anyway."));
 	return Exit_FAILURE;
     }
 
     bool ok;
 
-    finalize_shell();
     ok = send_sigstop_to_myself();
     if (!ok)
 	xerror(errno, Ngt("cannot send SIGSTOP signal"));
-    reinitialize_shell();
+    if (doing_job_control_now)
+	ensure_foreground();
     return ok ? Exit_SUCCESS : Exit_FAILURE;
 }
 

yash.h

@@ -25,12 +25,6 @@
 
 extern pid_t shell_pid, shell_pgid;
 
-extern void finalize_shell(void);
-extern void reinitialize_shell(void);
-extern void set_own_pgid(void);
-extern void reset_own_pgid(void);
-extern void forget_initial_pgid(void);
-
 static inline void exit_shell(void)
     __attribute__((noreturn));
 extern void exit_shell_with_status(int status)