svn commit: trunk/busybox: coreutils include libbb
landley at busybox.net
landley at busybox.net
Thu May 25 23:02:42 UTC 2006
Author: landley
Date: 2006-05-25 16:02:40 -0700 (Thu, 25 May 2006)
New Revision: 15172
Log:
Rich Felker suggested removing dprintf() from watch, and one thing led to
another... This adds bb_xspawn() support, which does vfork/exec. (I don't
know why using a static instead of a local adds ~40 bytes, but using
the local doesn't work...)
Modified:
trunk/busybox/coreutils/watch.c
trunk/busybox/include/libbb.h
trunk/busybox/libbb/xfuncs.c
Changeset:
Modified: trunk/busybox/coreutils/watch.c
===================================================================
--- trunk/busybox/coreutils/watch.c 2006-05-25 21:13:30 UTC (rev 15171)
+++ trunk/busybox/coreutils/watch.c 2006-05-25 23:02:40 UTC (rev 15172)
@@ -4,20 +4,7 @@
*
* Copyright (C) 2001 by Michael Habermann <mhabermann at gmx.de>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* BB_AUDIT SUSv3 N/A */
@@ -41,23 +28,18 @@
int watch_main(int argc, char **argv)
{
- const int header_len = 40;
- time_t t;
- pid_t pid;
+ int width, len;
unsigned period = 2;
- int old_stdout;
- int len, len2;
- char **watched_argv;
- char header[header_len + 1];
+ char **watched_argv, *header;
- if (argc < 2) {
- bb_show_usage();
- }
+ if (argc < 2) bb_show_usage();
+ get_terminal_width_height(1, &width, 0);
+ header = xzalloc(width--);
+
/* don't use getopt, because it permutes the arguments */
++argv;
- if ((argc > 3) && !strcmp(*argv, "-n")
- ) {
+ if ((argc > 3) && !strcmp(*argv, "-n")) {
period = bb_xgetularg10_bnd(argv[1], 1, UINT_MAX);
argv += 2;
}
@@ -65,44 +47,22 @@
/* create header */
- len = snprintf(header, header_len, "Every %ds:", period);
- /* Don't bother checking for len < 0, as it should never happen.
- * But, just to be prepared... */
- assert(len >= 0);
- do {
- len2 = strlen(*argv);
- if (len + len2 >= header_len-1) {
- break;
- }
- header[len] = ' ';
- memcpy(header+len+1, *argv, len2);
- len += len2+1;
- } while (*++argv);
+ len = snprintf(header, width, "Every %ds:", period);
+ while (*argv && len<width)
+ snprintf(header+len, width-len, " %s", *(argv++));
- header[len] = 0;
-
- /* thanks to lye, who showed me how to redirect stdin/stdout */
- old_stdout = dup(STDOUT_FILENO);
-
while (1) {
+ char *thyme;
+ time_t t;
+
time(&t);
- /* Use dprintf to avoid fflush()ing stdout. */
- if (dprintf(1, "\033[H\033[J%-*s%s\n", header_len, header, ctime(&t)) < 0) {
- bb_perror_msg_and_die("printf");
- }
+ thyme = ctime(&t);
+ len = strlen(thyme);
+ if (len < width) header[width-len] = 0;
+
+ printf("\033[H\033[J%s %s\n", header, thyme);
- pid = vfork(); /* vfork, because of ucLinux */
- if (pid > 0) {
- //parent
- wait(0);
- sleep(period);
- } else if (0 == pid) {
- //child
- dup2(old_stdout, STDOUT_FILENO);
- execvp(*watched_argv, watched_argv);
- bb_perror_msg_and_die("%s", *watched_argv);
- } else {
- bb_perror_msg_and_die("vfork");
- }
+ waitpid(bb_xspawn(watched_argv),0,0);
+ sleep(period);
}
}
Modified: trunk/busybox/include/libbb.h
===================================================================
--- trunk/busybox/include/libbb.h 2006-05-25 21:13:30 UTC (rev 15171)
+++ trunk/busybox/include/libbb.h 2006-05-25 23:02:40 UTC (rev 15172)
@@ -146,6 +146,8 @@
extern void xstat(const char *filename, struct stat *buf);
extern int bb_xsocket(int domain, int type, int protocol);
+extern pid_t bb_spawn(char **argv);
+extern pid_t bb_xspawn(char **argv);
extern void bb_xdaemon(int nochdir, int noclose);
extern void bb_xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen);
extern void bb_xlisten(int s, int backlog);
Modified: trunk/busybox/libbb/xfuncs.c
===================================================================
--- trunk/busybox/libbb/xfuncs.c 2006-05-25 21:13:30 UTC (rev 15171)
+++ trunk/busybox/libbb/xfuncs.c 2006-05-25 23:02:40 UTC (rev 15172)
@@ -182,3 +182,37 @@
}
}
#endif
+
+#ifdef L_spawn
+// This does a fork/exec in one call, using vfork().
+pid_t bb_spawn(char **argv)
+{
+ static int failed;
+ pid_t pid;
+
+ // Be nice to nommu machines.
+ failed = 0;
+ pid = vfork();
+ if (pid < 0) return pid;
+ if (!pid) {
+ execvp(*argv, argv);
+
+ // We're sharing a stack with blocked parent, let parent know we failed
+ // and then exit to unblock parent (but don't run atexit() stuff, which
+ // would screw up parent.)
+
+ failed = -1;
+ _exit(0);
+ }
+ return failed ? failed : pid;
+}
+#endif
+
+#ifdef L_xspawn
+pid_t bb_xspawn(char **argv)
+{
+ pid_t pid = bb_spawn(argv);
+ if (pid < 0) bb_perror_msg_and_die("%s", *argv);
+ return pid;
+}
+#endif
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