- pidof(8): make -s optional and optional -o; closes #168

  first cut.

3 files changed, 136 insertions, 33 deletions

diff --git a/include/usage.h b/include/usage.h
index fad50efdc..bef6a4dd2 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -2160,16 +2160,37 @@
         "$ patch -p1 <example.diff\n" \
         "$ patch -p0 -i example.diff"
 
+#if ENABLE_FEATURE_PIDOF_SINGLE
+#define USAGE_FEATURE_PIDOF_SINGLE(a) a
+#else
+#define USAGE_FEATURE_PIDOF_SINGLE(a)
+#endif
+#if ENABLE_FEATURE_PIDOF_OMIT
+#define USAGE_FEATURE_PIDOF_OMIT(a) a
+#else
+#define USAGE_FEATURE_PIDOF_OMIT(a)
+#endif
+#if (ENABLE_FEATURE_PIDOF_SINGLE || ENABLE_FEATURE_PIDOF_OMIT)
+#define USAGE_PIDOF "Options:"
+#else
+#define USAGE_PIDOF "\n\tThis version of pidof accepts no options."
+#endif
+
 #define pidof_trivial_usage \
         "process-name [OPTION] [process-name ...]"
+
 #define pidof_full_usage \
         "Lists the PIDs of all processes with names that match the\n" \
         "names on the command line.\n" \
-        "Options:\n" \
-        "\t-s\t\tdisplay only a single PID"
+        USAGE_PIDOF \
+        USAGE_FEATURE_PIDOF_SINGLE("\n\t-s\t\tdisplay only a single PID") \
+        USAGE_FEATURE_PIDOF_OMIT("\n\t-o\t\tomit given pid.") \
+        USAGE_FEATURE_PIDOF_OMIT("\n\t\t\tUse %PPID to omit the parent pid of pidof itself")
 #define pidof_example_usage \
         "$ pidof init\n" \
-        "1\n"
+        "1\n" \
+        USAGE_FEATURE_PIDOF_OMIT("$ pidof /bin/sh\n20351 5973 5950\n") \
+        USAGE_FEATURE_PIDOF_OMIT("$ pidof /bin/sh -o %PPID\n20351 5950")
 
 #ifndef CONFIG_FEATURE_FANCY_PING
 #define ping_trivial_usage "host"
diff --git a/procps/Config.in b/procps/Config.in
index d17bbcde7..b4832db6b 100644
--- a/procps/Config.in
+++ b/procps/Config.in
@@ -37,6 +37,22 @@ config CONFIG_PIDOF
           Pidof finds the process id's (pids) of the named programs. It prints
           those id's on the standard output.
 
+config CONFIG_FEATURE_PIDOF_SINGLE
+        bool "  Enable argument for single shot (-s)"
+        default n
+        depends on CONFIG_PIDOF
+        help
+          Support argument '-s' for returning only the first pid found.
+
+config CONFIG_FEATURE_PIDOF_OMIT
+        bool "  Enable argument for omitting pids (-o)"
+        default n
+        depends on CONFIG_PIDOF
+        help
+          Support argument '-o' for omitting the given pids in output.
+          The special pid %PPID can be used to name the parent process
+          of the pidof, in other words the calling shell or shell script.
+
 config CONFIG_PS
         bool "ps"
         default n
diff --git a/procps/pidof.c b/procps/pidof.c
index 413864a37..6f959e4ad 100644
--- a/procps/pidof.c
+++ b/procps/pidof.c
@@ -4,20 +4,7 @@
  *
  * Copyright (C) 1999-2004 by Erik Andersen <andersen@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 the GPL v2, see the file LICENSE in this tarball.
  */
 
 
@@ -31,41 +18,120 @@
 #include <unistd.h>
 #include "busybox.h"
 
+#if ENABLE_FEATURE_PIDOF_SINGLE
+#define _SINGLE_COMPL(a) a
+#define SINGLE (1<<0)
+#else
+#define _SINGLE_COMPL(a)
+#define SINGLE (0)
+#endif
+
+#if ENABLE_FEATURE_PIDOF_OMIT
+#define _OMIT_COMPL(a) a
+#define _OMIT(a) ,a
+static llist_t *omits; /* list of pids to omit */
+#if ENABLE_FEATURE_PIDOF_SINGLE
+#define OMIT (1<<1)
+#else
+#define OMIT (1<<0)
+#endif
+#else
+#define _OMIT_COMPL(a) ""
+#define _OMIT(a)
+#define OMIT (0)
+#endif
 
 extern int pidof_main(int argc, char **argv)
 {
-        int opt, n = 0;
-        int single_flag = 0;
+        int n = 0;
         int fail = 1;
+        unsigned long int opt;
+#if ENABLE_FEATURE_PIDOF_OMIT
+        bb_opt_complementally = _OMIT_COMPL("o*");
+#endif
 
-        /* do normal option parsing */
-        while ((opt = getopt(argc, argv, "s")) > 0) {
-                switch (opt) {
-                        case 's':
-                                single_flag = 1;
-                                break;
-                        default:
-                                bb_show_usage();
-                }
+        /* do option parsing */
+        if ((opt = bb_getopt_ulflags(argc, argv,
+                                        _SINGLE_COMPL("s") _OMIT_COMPL("o:")
+                                        _OMIT(&omits)))
+                        > 0) {
+#if ENABLE_FEATURE_PIDOF_SINGLE
+                if (!(opt & SINGLE))
+#endif
+#if ENABLE_FEATURE_PIDOF_OMIT
+                if (!(opt & OMIT))
+#endif
+                bb_show_usage();
         }
 
-        /* Looks like everything is set to go. */
+#if ENABLE_FEATURE_PIDOF_OMIT
+        /* fill omit list.  */
+        {
+        RESERVE_CONFIG_BUFFER(getppid_str, 32);
+        llist_t * omits_p = omits;
+        while (omits_p) {
+                /* are we asked to exclude the parent's process ID?  */
+                if (omits_p->data[0] == '%') {
+                        if (!strncmp(omits_p->data, "%PPID", 5)) {
+                                /* yes, exclude ppid */
+                                snprintf(getppid_str, sizeof(getppid_str), "%ld", getppid());
+//                              omits_p->data = getppid_str;
+#if 0
+                        } else {
+                                bb_error_msg_and_die("illegal omit pid value (%s)!\n",
+                                                omits_p->data);
+#endif
+                        }
+                } else {
+                /* no, not talking about ppid but deal with usual case (pid).  */
+                        snprintf(getppid_str, sizeof(getppid_str), "%ld",
+                                        strtol(omits_p->data, NULL, 10));
+                }
+                omits_p->data = getppid_str;
+                omits_p = omits_p->link;
+        }
+        RELEASE_CONFIG_BUFFER(getppid_str);
+        }
+#endif
+        /* Looks like everything is set to go.  */
         while(optind < argc) {
                 long *pidList;
                 long *pl;
 
-                pidList = find_pid_by_name(argv[optind]);
+                /* reverse the pidlist like GNU pidof does.  */
+                pidList = pidlist_reverse(find_pid_by_name(argv[optind]));
                 for(pl = pidList; *pl > 0; pl++) {
+#if ENABLE_FEATURE_PIDOF_OMIT
+                        unsigned short omitted = 0;
+                        if (opt & OMIT) {
+                                llist_t *omits_p = omits;
+                                while (omits_p)
+                                        if (strtol(omits_p->data, NULL, 10) == *pl) {
+                                                omitted = 1; break;
+                                        } else
+                                                omits_p = omits_p->link;
+                        }
+                        if (!omitted)
+#endif
                         printf("%s%ld", (n++ ? " " : ""), *pl);
+#if ENABLE_FEATURE_PIDOF_OMIT
+                        fail = omitted;
+#else
                         fail = 0;
-                        if (single_flag)
+#endif
+#if ENABLE_FEATURE_PIDOF_SINGLE
+                        if (opt & SINGLE)
                                 break;
+#endif
                 }
                 free(pidList);
                 optind++;
-
         }
-        printf("\n");
+        putchar('\n');
 
+#if ENABLE_FEATURE_PIDOF_OMIT
+        if (ENABLE_FEATURE_CLEAN_UP)
+                llist_free(omits);
+#endif
         return fail ? EXIT_FAILURE : EXIT_SUCCESS;
 }