usage.c: remove reference to busybox.h

[oweals/busybox.git] / coreutils / watch.c

diff --git a/coreutils/watch.c b/coreutils/watch.c
index 78ede4c1ce30f41ce9a91433250ddfaf424ed7a7..2ad0564cd7c226d44d3396a699471b9160186d53 100644 (file)
--- a/coreutils/watch.c
+++ b/coreutils/watch.c
@@ -3,102 +3,78 @@
  * Mini watch implementation for busybox
  *
  * Copyright (C) 2001 by Michael Habermann <mhabermann@gmx.de>
+ * Copyrigjt (C) Mar 16, 2003 Manuel Novoa III   (mjn3@codepoet.org)
  *
- * 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.
  */
 
-/* getopt not needed */
+/* BB_AUDIT SUSv3 N/A */
+/* BB_AUDIT GNU defects -- only option -n is supported. */
 
-#include <stdio.h>
-#include <errno.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <string.h>
-#include "busybox.h"
+#include "libbb.h"
 
-extern int watch_main(int argc, char **argv)
-{
-       const char date_argv[2][10] = { "date", "" };
-       const char clrscr[] =
-               "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n";
-       const int header_len = 40;
-       char header[header_len + 1];
-       int period = 2;
-       char **cargv;
-       int cargc;
-       pid_t pid;
-       int old_stdout;
-       int i;
+// procps 2.0.18:
+// watch [-d] [-n seconds]
+//   [--differences[=cumulative]] [--interval=seconds] command
+//
+// procps-3.2.3:
+// watch [-dt] [-n seconds]
+//   [--differences[=cumulative]] [--interval=seconds] [--no-title] command
+//
+// (procps 3.x and procps 2.x are forks, not newer/older versions of the same)
 
-       if (argc < 2) {
-               show_usage();
-       } else {
-               cargv = argv + 1;
-               cargc = argc - 1;
-
-               /* don't use getopt, because it permutes the arguments */
-               if (argc >= 3 && !strcmp(argv[1], "-n")) {
-                       period = strtol(argv[2], NULL, 10);
-                       if (period < 1)
-                               show_usage();
-                       cargv += 2;
-                       cargc -= 2;
-               }
-       }
+int watch_main(int argc, char **argv);
+int watch_main(int argc, char **argv)
+{
+       unsigned opt;
+       unsigned period = 2;
+       unsigned cmdlen = 1; // 1 for terminal NUL
+       char *header = NULL;
+       char *cmd;
+       char *tmp;
+       char **p;
 
+       opt_complementary = "-1"; // at least one param please
+       opt = getopt32(argc, argv, "+dtn:", &tmp);
+       //if (opt & 0x1) // -d (ignore)
+       //if (opt & 0x2) // -t
+       if (opt & 0x4) period = xatou(tmp);
+       argv += optind;
 
-       /* create header */
-       snprintf(header, header_len, "Every %ds: ", period);
-       for (i = 0; i < cargc && (strlen(header) + strlen(cargv[i]) < header_len);
-                i++) {
-               strcat(header, cargv[i]);
-               strcat(header, " ");
+       p = argv;
+       while (*p)
+               cmdlen += strlen(*p++) + 1;
+       tmp = cmd = xmalloc(cmdlen);
+       while (*argv) {
+               tmp += sprintf(tmp, " %s", *argv);
+               argv++;
        }
-
-       /* fill with blanks */
-       for (i = strlen(header); i < header_len; i++)
-               header[i] = ' ';
-
-       header[header_len - 1] = '\0';
-
-
-       /* thanks to lye, who showed me how to redirect stdin/stdout */
-       old_stdout = dup(1);
+       cmd++; // skip initial space
 
        while (1) {
-               printf("%s%s", clrscr, header);
-               date_main(1, (char **) date_argv);
-               printf("\n");
+               printf("\033[H\033[J");
+               if (!(opt & 0x2)) { // no -t
+                       int width, len;
+                       char *thyme;
+                       time_t t;
 
-               pid = vfork();  /* vfork, because of ucLinux */
-               if (pid > 0) {
-                       //parent
-                       wait(0);
-                       sleep(period);
-               } else if (0 == pid) {
-                       //child
-                       close(1);
-                       dup(old_stdout);
-                       if (execvp(*cargv, cargv))
-                               error_msg_and_die("Couldn't run command\n");
-               } else {
-                       error_msg_and_die("Couldn't vfork\n");
+                       get_terminal_width_height(STDOUT_FILENO, &width, 0);
+                       header = xrealloc(header, width--);
+                       // '%-*s' pads header with spaces to the full width
+                       snprintf(header, width, "Every %ds: %-*s", period, width, cmd);
+                       time(&t);
+                       thyme = ctime(&t);
+                       len = strlen(thyme);
+                       if (len < width)
+                               strcpy(header + width - len, thyme);
+                       puts(header);
                }
+               fflush(stdout);
+               // TODO: 'real' watch pipes cmd's output to itself
+               // and does not allow it to overflow the screen
+               // (taking into account linewrap!)
+               system(cmd);
+               sleep(period);
        }
-
-
-       return EXIT_SUCCESS;
+       return 0; // gcc thinks we can reach this :)
 }