pgrep/pkill: support -s and -P options

function                                             old     new   delta
pgrep_main                                           510     580     +70
packed_usage                                       26575   26616     +41
act                                                  234     236      +2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/0 up/down: 113/0)             Total: 113 bytes

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 64 insertions, 54 deletions

diff --git a/procps/pgrep.c b/procps/pgrep.c
index 0e8e5294e..aef4f229a 100644
--- a/procps/pgrep.c
+++ b/procps/pgrep.c
@@ -6,7 +6,6 @@
  *
  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  */
-
 #include "libbb.h"
 #include "xregex.h"
 
@@ -15,26 +14,30 @@
 #define pkill (ENABLE_PKILL && applet_name[1] == 'k')
 
 enum {
-        /* "vlfxon" */
-        PGREPOPTBIT_V = 0, /* must be first, we need OPT_INVERT = 0/1 */
-        PGREPOPTBIT_L,
-        PGREPOPTBIT_F,
-        PGREPOPTBIT_X,
-        PGREPOPTBIT_O,
-        PGREPOPTBIT_N,
+        /* "vlfxons:P:" */
+        OPTBIT_V = 0, /* must be first, we need OPT_INVERT = 0/1 */
+        OPTBIT_L,
+        OPTBIT_F,
+        OPTBIT_X,
+        OPTBIT_O,
+        OPTBIT_N,
+        OPTBIT_S,
+        OPTBIT_P,
 };
 
-#define OPT_INVERT      (opt & (1 << PGREPOPTBIT_V))
-#define OPT_LIST        (opt & (1 << PGREPOPTBIT_L))
-#define OPT_FULL        (opt & (1 << PGREPOPTBIT_F))
-#define OPT_ANCHOR      (opt & (1 << PGREPOPTBIT_X))
-#define OPT_FIRST       (opt & (1 << PGREPOPTBIT_O))
-#define OPT_LAST        (opt & (1 << PGREPOPTBIT_N))
+#define OPT_INVERT      (opt & (1 << OPTBIT_V))
+#define OPT_LIST        (opt & (1 << OPTBIT_L))
+#define OPT_FULL        (opt & (1 << OPTBIT_F))
+#define OPT_ANCHOR      (opt & (1 << OPTBIT_X))
+#define OPT_FIRST       (opt & (1 << OPTBIT_O))
+#define OPT_LAST        (opt & (1 << OPTBIT_N))
+#define OPT_SID         (opt & (1 << OPTBIT_S))
+#define OPT_PPID        (opt & (1 << OPTBIT_P))
 
-static void act(unsigned pid, char *cmd, int signo, unsigned opt)
+static void act(unsigned pid, char *cmd, int signo)
 {
         if (pgrep) {
-                if (OPT_LIST)
+                if (option_mask32 & (1 << OPTBIT_L)) /* OPT_LIST */
                         printf("%d %s\n", pid, cmd);
                 else
                         printf("%d\n", pid);
@@ -45,13 +48,12 @@ static void act(unsigned pid, char *cmd, int signo, unsigned opt)
 int pgrep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int pgrep_main(int argc UNUSED_PARAM, char **argv)
 {
-        unsigned pid = getpid();
-        int signo = SIGTERM;
+        unsigned pid;
+        int signo;
         unsigned opt;
-        int scan_mask = PSSCAN_COMM;
-        char *first_arg;
-        int first_arg_idx;
+        int scan_mask;
         int matched_pid;
+        int sid2match, ppid2match;
         char *cmd_last;
         procps_status_t *proc;
         /* These are initialized to 0 */
@@ -64,52 +66,52 @@ int pgrep_main(int argc UNUSED_PARAM, char **argv)
 
         memset(&Z, 0, sizeof(Z));
 
-        /* We must avoid interpreting -NUM (signal num) as an option */
-        first_arg_idx = 1;
-        while (1) {
-                first_arg = argv[first_arg_idx];
-                if (!first_arg)
-                        break;
-                /* not "-<small_letter>..."? */
-                if (first_arg[0] != '-' || first_arg[1] < 'a' || first_arg[1] > 'z') {
-                        argv[first_arg_idx] = NULL; /* terminate argv here */
-                        break;
+        /* Parse -SIGNAL for pkill. Must be first option, if present */
+        signo = SIGTERM;
+        if (pkill && argv[1] && argv[1][0] == '-') {
+                int temp = get_signum(argv[1]+1);
+                if (temp != -1) {
+                        signo = temp;
+                        argv++;
                 }
-                first_arg_idx++;
         }
-        opt = getopt32(argv, "vlfxon");
-        argv[first_arg_idx] = first_arg;
 
+        /* Parse remaining options */
+        ppid2match = -1;
+        sid2match = -1;
+        opt_complementary = "s+:P+"; /* numeric opts */
+        opt = getopt32(argv, "vlfxons:P:", &sid2match, &ppid2match);
         argv += optind;
-        //argc -= optind; - unused anyway
-        if (OPT_FULL)
-                scan_mask |= PSSCAN_ARGVN;
 
-        if (pkill) {
-                if (OPT_LIST) { /* -l: print the whole signal list */
-                        print_signames();
-                        return 0;
-                }
-                if (first_arg && first_arg[0] == '-') {
-                        signo = get_signum(&first_arg[1]);
-                        if (signo < 0) /* || signo > MAX_SIGNUM ? */
-                                bb_error_msg_and_die("bad signal name '%s'", &first_arg[1]);
-                        argv++;
-                }
+        if (pkill && OPT_LIST) { /* -l: print the whole signal list */
+                print_signames();
+                return 0;
         }
 
-        /* One pattern is required */
-        if (!argv[0] || argv[1])
+        pid = getpid();
+        if (sid2match == 0)
+                sid2match = getsid(pid);
+
+        scan_mask = PSSCAN_COMM;
+        if (OPT_FULL)
+                scan_mask |= PSSCAN_ARGVN;
+
+        /* One pattern is required, if no -s and no -P */
+        if ((sid2match & ppid2match) < 0 && (!argv[0] || argv[1]))
                 bb_show_usage();
 
-        xregcomp(&re_buffer, argv[0], 0);
+        if (argv[0])
+                xregcomp(&re_buffer, argv[0], 0);
+
         matched_pid = 0;
         cmd_last = NULL;
         proc = NULL;
         while ((proc = procps_scan(proc, scan_mask)) != NULL) {
                 char *cmd;
+
                 if (proc->pid == pid)
                         continue;
+
                 cmd = proc->argv0;
                 if (!cmd) {
                         cmd = proc->comm;
@@ -120,8 +122,15 @@ int pgrep_main(int argc UNUSED_PARAM, char **argv)
                                 i--;
                         }
                 }
+
+                if (ppid2match >= 0 && ppid2match != proc->ppid)
+                        continue;
+                if (sid2match >= 0  && sid2match != proc->sid)
+                        continue;
+
                 /* NB: OPT_INVERT is always 0 or 1 */
-                if ((regexec(&re_buffer, cmd, 1, re_match, 0) == 0 /* match found */
+                if (!argv[0] ||
+                    (regexec(&re_buffer, cmd, 1, re_match, 0) == 0 /* match found */
                      && (!OPT_ANCHOR || (re_match[0].rm_so == 0 && re_match[0].rm_eo == (regoff_t)strlen(cmd)))) ^ OPT_INVERT
                 ) {
                         matched_pid = proc->pid;
@@ -130,13 +139,14 @@ int pgrep_main(int argc UNUSED_PARAM, char **argv)
                                 cmd_last = xstrdup(cmd);
                                 continue;
                         }
-                        act(proc->pid, cmd, signo, opt);
+                        act(proc->pid, cmd, signo);
                         if (OPT_FIRST)
                                 break;
                 }
         }
+
         if (cmd_last) {
-                act(matched_pid, cmd_last, signo, opt);
+                act(matched_pid, cmd_last, signo);
                 if (ENABLE_FEATURE_CLEAN_UP)
                         free(cmd_last);
         }