start_stop_daemon: add -N <nice> compat

[re]nice: add support for -nNNN w/o spaces, -NNN (nice only),
          simplified code

6 files changed, 87 insertions, 92 deletions

diff --git a/coreutils/nice.c b/coreutils/nice.c
index a347001e3..dbd90648d 100644
--- a/coreutils/nice.c
+++ b/coreutils/nice.c
@@ -7,39 +7,14 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <limits.h>
-#include <errno.h>
-#include <unistd.h>
 #include <sys/resource.h>
 #include "busybox.h"
 
-static inline int int_add_no_wrap(int a, int b)
-{
-        int s = a + b;
-
-        if (b < 0) {
-                if (s > a) s = INT_MIN;
-        } else {
-                if (s < a) s = INT_MAX;
-        }
-
-        return s;
-}
-
 int nice_main(int argc, char **argv)
 {
-        static const char Xetpriority_msg[] = "cannot %cet priority";
-
         int old_priority, adjustment;
 
-        errno = 0;                       /* Needed for getpriority error detection. */
         old_priority = getpriority(PRIO_PROCESS, 0);
-        if (errno) {
-                bb_perror_msg_and_die(Xetpriority_msg, 'g');
-        }
 
         if (!*++argv) { /* No args, so (GNU) output current nice value. */
                 bb_printf("%d\n", old_priority);
@@ -48,19 +23,26 @@ int nice_main(int argc, char **argv)
 
         adjustment = 10;                        /* Set default adjustment. */
 
-        if ((argv[0][0] == '-') && (argv[0][1] == 'n') && !argv[0][2]) { /* "-n" */
+        if (argv[0][0] == '-') {
+                if (argv[0][1] == 'n') { /* -n */
+                        if (argv[0][2]) { /* -nNNNN (w/o space) */
+                                argv[0] += 2; argv--; argc++;
+                        }
+                } else { /* -NNN (NNN may be negative) == -n NNN */
+                        argv[0] += 1; argv--; argc++;
+                }
                 if (argc < 4) {                 /* Missing priority and/or utility! */
                         bb_show_usage();
                 }
-                adjustment = xatoi(argv[1]);
+                adjustment = xatoi_range(argv[1], INT_MIN/2, INT_MAX/2);
                 argv += 2;
         }
 
-        {  /* Set our priority.  Handle integer wrapping for old + adjust. */
-                int new_priority = int_add_no_wrap(old_priority, adjustment);
+        {  /* Set our priority. */
+                int prio = old_priority + adjustment;
 
-                if (setpriority(PRIO_PROCESS, 0, new_priority) < 0) {
-                        bb_perror_msg_and_die(Xetpriority_msg, 's');
+                if (setpriority(PRIO_PROCESS, 0, prio) < 0) {
+                        bb_perror_msg_and_die("setpriority(%d)", prio);
                 }
         }
 
diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c
index 6ced9caad..a9f82c5cc 100644
--- a/debianutils/start_stop_daemon.c
+++ b/debianutils/start_stop_daemon.c
@@ -10,6 +10,7 @@
 
 #include "busybox.h"
 #include <getopt.h>
+#include <sys/resource.h>
 
 static int signal_nr = 15;
 static int user_id = -1;
@@ -191,38 +192,39 @@ static int do_stop(void)
 
 #if ENABLE_FEATURE_START_STOP_DAEMON_LONG_OPTIONS
 static const struct option ssd_long_options[] = {
-        { "stop",                       0,              NULL,           'K' },
-        { "start",                      0,              NULL,           'S' },
-        { "background",         0,              NULL,           'b' },
-        { "quiet",                      0,              NULL,           'q' },
-        { "make-pidfile",       0,              NULL,           'm' },
+        { "stop",               0,      NULL,   'K' },
+        { "start",              0,      NULL,   'S' },
+        { "background",         0,      NULL,   'b' },
+        { "quiet",              0,      NULL,   'q' },
+        { "make-pidfile",       0,      NULL,   'm' },
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
-        { "oknodo",                     0,              NULL,           'o' },
-        { "verbose",            0,              NULL,           'v' },
+        { "oknodo",             0,      NULL,   'o' },
+        { "verbose",            0,      NULL,   'v' },
+        { "nicelevel",          1,      NULL,   'N' },
 #endif
-        { "startas",            1,              NULL,           'a' },
-        { "name",                       1,              NULL,           'n' },
-        { "signal",                     1,              NULL,           's' },
-        { "user",                       1,              NULL,           'u' },
-        { "chuid",                      1,              NULL,           'c' },
-        { "exec",                       1,              NULL,           'x' },
-        { "pidfile",            1,              NULL,           'p' },
+        { "startas",            1,      NULL,   'a' },
+        { "name",               1,      NULL,   'n' },
+        { "signal",             1,      NULL,   's' },
+        { "user",               1,      NULL,   'u' },
+        { "chuid",              1,      NULL,   'c' },
+        { "exec",               1,      NULL,   'x' },
+        { "pidfile",            1,      NULL,   'p' },
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
-        { "retry",                      1,              NULL,           'R' },
+        { "retry",              1,      NULL,   'R' },
 #endif
-        { 0,                            0,              0,              0 }
+        { 0,                    0,      0,      0 }
 };
 #endif
 
-#define SSD_CTX_STOP            1
-#define SSD_CTX_START           2
-#define SSD_OPT_BACKGROUND      4
-#define SSD_OPT_QUIET           8
-#define SSD_OPT_MAKEPID         16
+#define SSD_CTX_STOP            0x1
+#define SSD_CTX_START           0x2
+#define SSD_OPT_BACKGROUND      0x4
+#define SSD_OPT_QUIET           0x8
+#define SSD_OPT_MAKEPID         0x10
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
-#define SSD_OPT_OKNODO          32
-#define SSD_OPT_VERBOSE         64
-
+#define SSD_OPT_OKNODO          0x20
+#define SSD_OPT_VERBOSE         0x40
+#define SSD_OPT_NICELEVEL       0x80
 #endif
 
 int start_stop_daemon_main(int argc, char **argv)
@@ -233,6 +235,7 @@ int start_stop_daemon_main(int argc, char **argv)
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
 //      char *retry_arg = NULL;
 //      int retries = -1;
+        char *opt_N;
 #endif
 #if ENABLE_FEATURE_START_STOP_DAEMON_LONG_OPTIONS
         applet_long_options = ssd_long_options;
@@ -241,9 +244,10 @@ int start_stop_daemon_main(int argc, char **argv)
         /* Check required one context option was given */
         opt_complementary = "K:S:?:K--S:S--K:m?p:K?xpun:S?xa";
         opt = getopt32(argc, argv, "KSbqm"
-//              USE_FEATURE_START_STOP_DAEMON_FANCY("ovR:")
-                USE_FEATURE_START_STOP_DAEMON_FANCY("ov")
+//              USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:R:")
+                USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:")
                 "a:n:s:u:c:x:p:"
+                USE_FEATURE_START_STOP_DAEMON_FANCY(,&opt_N)
 //              USE_FEATURE_START_STOP_DAEMON_FANCY(,&retry_arg)
                 ,&startas, &cmdname, &signame, &userspec, &chuid, &execname, &pidfile);
 
@@ -279,7 +283,7 @@ int start_stop_daemon_main(int argc, char **argv)
 
         if (found) {
                 if (!quiet)
-                        printf("%s already running.\n%d\n", execname ,found->pid);
+                        printf("%s already running\n%d\n", execname, found->pid);
                 USE_FEATURE_START_STOP_DAEMON_FANCY(return !(opt & SSD_OPT_OKNODO);)
                 SKIP_FEATURE_START_STOP_DAEMON_FANCY(return EXIT_FAILURE;)
         }
@@ -296,11 +300,20 @@ int start_stop_daemon_main(int argc, char **argv)
                 fprintf(pidf, "%d\n", pidt);
                 fclose(pidf);
         }
-        if(chuid) {
-                if(sscanf(chuid, "%d", &user_id) != 1)
+        if (chuid) {
+                if (sscanf(chuid, "%d", &user_id) != 1)
                         user_id = bb_xgetpwnam(chuid);
-                setuid(user_id);
+                xsetuid(user_id);
         }
+#if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
+        if (opt & SSD_OPT_NICELEVEL) {
+                /* Set process priority */
+                int prio = getpriority(PRIO_PROCESS, 0) + xatoi_range(opt_N, INT_MIN/2, INT_MAX/2);
+                if (setpriority(PRIO_PROCESS, 0, prio) < 0) {
+                        bb_perror_msg_and_die("setpriority(%d)", prio);
+                }
+        }
+#endif
         execv(startas, argv);
         bb_perror_msg_and_die ("unable to start %s", startas);
 }
diff --git a/include/libbb.h b/include/libbb.h
index bc86e5faf..7b9b83908 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -346,6 +346,7 @@ long xatol_sfx(const char *numstr, const struct suffix_mult *suffixes);
 long xatol(const char *numstr);
 /* Specialized: */
 unsigned xatou(const char *numstr);
+int xatoi_range(const char *numstr, int lower, int upper);
 int xatoi(const char *numstr);
 /* Using xatoi() instead of naive atoi() is not always convenient -
  * in many places people want *non-negative* values, but store them
diff --git a/include/usage.h b/include/usage.h
index c9e501903..ef348a2a9 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -2691,6 +2691,7 @@ USE_FEATURE_MDEV_CONFIG( \
 USE_FEATURE_START_STOP_DAEMON_FANCY( \
         "\n\t-o|--oknodo\t\t\texit status 0 if nothing done" \
         "\n\t-v|--verbose\t\t\tbe verbose" \
+        "\n\t-N|--nicelevel <N>\t\tadd N to process's nice level" \
 ) \
         "\n\t-s|--signal <signal>\t\tsignal to send (default TERM)" \
         "\n\t-U|--chuid <username>|<uid>\tstart process with this name"
diff --git a/libbb/xatol.c b/libbb/xatol.c
index 82250a7bb..3316c3d06 100644
--- a/libbb/xatol.c
+++ b/libbb/xatol.c
@@ -189,6 +189,11 @@ unsigned xatou(const char *numstr)
         return xatoul_range(numstr, 0, UINT_MAX);
 }
 
+int xatoi_range(const char *numstr, int lower, int upper)
+{
+        return xatol_range(numstr, lower, upper);
+}
+
 int xatoi(const char *numstr)
 {
         return xatol_range(numstr, INT_MIN, INT_MAX);
diff --git a/procps/renice.c b/procps/renice.c
index a91328f53..bcaa94cf1 100644
--- a/procps/renice.c
+++ b/procps/renice.c
@@ -38,68 +38,61 @@
 #error Assumption violated : PRIO_USER value
 #endif
 
-static inline int int_add_no_wrap(int a, int b)
-{
-        int s = a + b;
-
-        if (b < 0) {
-                if (s > a) s = INT_MIN;
-        } else {
-                if (s < a) s = INT_MAX;
-        }
-
-        return s;
-}
-
 int renice_main(int argc, char **argv)
 {
-        static const char Xetpriority_msg[] = "%d: %cetpriority";
+        static const char Xetpriority_msg[] = "%cetpriority";
 
         int retval = EXIT_SUCCESS;
         int which = PRIO_PROCESS;       /* Default 'which' value. */
         int use_relative = 0;
         int adjustment, new_priority;
         unsigned who;
+        char *arg;
 
-        ++argv;
+        arg = *++argv;
 
         /* Check if we are using a relative adjustment. */
-        if (argv[0] && (argv[0][0] == '-') && (argv[0][1] == 'n') && !argv[0][2]) {
+        if (arg && arg[0] == '-' && arg[1] == 'n') {
                 use_relative = 1;
-                ++argv;
+                if (!arg[2])
+                        arg = *++argv;
+                else
+                        arg += 2;
         }
 
-        if (!*argv) {                           /* No args?  Then show usage. */
+        if (!arg) {                             /* No args?  Then show usage. */
                 bb_show_usage();
         }
 
         /* Get the priority adjustment (absolute or relative). */
-        adjustment = xatoi(*argv);
+        adjustment = xatoi_range(arg, INT_MIN/2, INT_MAX/2);
 
-        while (*++argv) {
+        while ((arg = *++argv) != NULL) {
                 /* Check for a mode switch. */
-                if ((argv[0][0] == '-') && argv[0][1] && !argv[0][2]) {
+                if (arg[0] == '-' && arg[1]) {
                         static const char opts[]
                                 = { 'p', 'g', 'u', 0, PRIO_PROCESS, PRIO_PGRP, PRIO_USER };
-                        const char *p = strchr(opts, argv[0][1]);
+                        const char *p = strchr(opts, arg[1]);
                         if (p) {
                                 which = p[4];
-                                continue;
+                                if (!arg[2])
+                                        continue;
+                                arg += 2;
                         }
                 }
 
                 /* Process an ID arg. */
                 if (which == PRIO_USER) {
                         struct passwd *p;
-                        p = getpwnam(*argv);
+                        p = getpwnam(arg);
                         if (!p) {
-                                bb_error_msg("unknown user: %s", *argv);
+                                bb_error_msg("unknown user: %s", arg);
                                 goto HAD_ERROR;
                         }
                         who = p->pw_uid;
                 } else {
-                        if (safe_strtou(*argv, &who)) {
-                                bb_error_msg("bad value: %s", *argv);
+                        if (safe_strtou(arg, &who)) {
+                                bb_error_msg("bad value: %s", arg);
                                 goto HAD_ERROR;
                         }
                 }
@@ -111,11 +104,11 @@ int renice_main(int argc, char **argv)
                         errno = 0;       /* Needed for getpriority error detection. */
                         old_priority = getpriority(which, who);
                         if (errno) {
-                                bb_perror_msg(Xetpriority_msg, who, 'g');
+                                bb_perror_msg(Xetpriority_msg, 'g');
                                 goto HAD_ERROR;
                         }
 
-                        new_priority = int_add_no_wrap(old_priority, adjustment);
+                        new_priority = old_priority + adjustment;
                 } else {
                         new_priority = adjustment;
                 }
@@ -124,8 +117,8 @@ int renice_main(int argc, char **argv)
                         continue;
                 }
 
-                bb_perror_msg(Xetpriority_msg, who, 's');
-        HAD_ERROR:
+                bb_perror_msg(Xetpriority_msg, 's');
+ HAD_ERROR:
                 retval = EXIT_FAILURE;
         }