2005-06-30 Shaun Jackman <sjackman@gmail.com>

        * loginutils/getty.c: (open_tty): Use dup2 instead of close/dup.



git-svn-id: svn://busybox.net/trunk/busybox@10681 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 14 insertions, 16 deletions

diff --git a/loginutils/getty.c b/loginutils/getty.c
index d123d4965..9648a1742 100644
--- a/loginutils/getty.c
+++ b/loginutils/getty.c
@@ -25,13 +25,14 @@
 #include <fcntl.h>
 #include <stdarg.h>
 #include <ctype.h>
-#ifdef CONFIG_FEATURE_UTMP
-#include <utmp.h>
-#endif
 #include <getopt.h>
 #include <termios.h>
 #include "busybox.h"
 
+#ifdef CONFIG_FEATURE_UTMP
+#include <utmp.h>
+#endif
+
 #define _PATH_LOGIN     "/bin/login"
 
  /* If USE_SYSLOG is undefined all diagnostics go directly to /dev/console. */
@@ -153,7 +154,7 @@ struct options {
 
 /* Storage for things detected while the login name was read. */
 
-static struct chardata {
+struct chardata {
         int erase;                                      /* erase character */
         int kill;                                       /* kill character */
         int eol;                                        /* end-of-line character */
@@ -233,9 +234,11 @@ static int caps_lock(const char *s);
 static int bcode(char *s);
 static void error(const char *fmt, ...) __attribute__ ((noreturn));
 
+#ifdef  SYSV_STYLE
 #ifdef CONFIG_FEATURE_UTMP
 static void update_utmp(char *line);
 #endif
+#endif
 
 /* The following is used for understandable diagnostics. */
 
@@ -552,16 +555,11 @@ static void update_utmp(char *line)
 /* open_tty - set up tty as standard { input, output, error } */
 static void open_tty(char *tty, struct termio *tp, int local)
 {
-        /* Get rid of the present standard { output, error} if any. */
-
-        (void) close(1);
-        (void) close(2);
-        errno = 0;                                      /* ignore above errors */
-
         /* Set up new standard input, unless we are given an already opened port. */
 
         if (strcmp(tty, "-")) {
                 struct stat st;
+                int fd;
 
                 /* Sanity checks... */
 
@@ -574,12 +572,11 @@ static void open_tty(char *tty, struct termio *tp, int local)
 
                 /* Open the tty as standard input. */
 
-                (void) close(0);
-                errno = 0;                              /* ignore close(2) errors */
-
                 debug("open(2)\n");
-                if (open(tty, O_RDWR | O_NONBLOCK, 0) != 0)
+                fd = open(tty, O_RDWR | O_NONBLOCK, 0);
+                if (dup2(fd, STDIN_FILENO) == -1)
                         error("/dev/%s: cannot open as standard input: %m", tty);
+                close(fd);
 
         } else {
 
@@ -592,9 +589,10 @@ static void open_tty(char *tty, struct termio *tp, int local)
                         error("%s: not open for read/write", tty);
         }
 
-        /* Set up standard output and standard error file descriptors. */
+        /* Replace current standard output/error fd's with new ones */
         debug("duping\n");
-        if (dup(0) != 1 || dup(0) != 2) /* set up stdout and stderr */
+        if (dup2(STDIN_FILENO, STDOUT_FILENO) == -1 ||
+            dup2(STDIN_FILENO, STDERR_FILENO) == -1)
                 error("%s: dup problem: %m", tty);      /* we have a problem */
 
         /*