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-rw-r--r--include/applets.h1
-rw-r--r--include/usage.h16
-rw-r--r--miscutils/Config.in7
-rw-r--r--miscutils/Kbuild1
-rw-r--r--miscutils/chrt.c124
-rw-r--r--scripts/defconfig1
6 files changed, 150 insertions, 0 deletions
diff --git a/include/applets.h b/include/applets.h
index d1bf0f3..214e63a 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -74,6 +74,7 @@ USE_CHMOD(APPLET(chmod, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_CHOWN(APPLET(chown, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_CHPST(APPLET(chpst, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
USE_CHROOT(APPLET(chroot, _BB_DIR_USR_SBIN, _BB_SUID_NEVER))
+USE_CHRT(APPLET(chrt, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
USE_CHVT(APPLET(chvt, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
USE_CKSUM(APPLET(cksum, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
USE_CLEAR(APPLET(clear, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
diff --git a/include/usage.h b/include/usage.h
index d8faa4f..4d1ecb8 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -382,6 +382,22 @@
#define bbsh_full_usage \
"The bbsh shell (command interpreter)"
+#define chrt_trivial_usage \
+ "[OPTION]... [prio] [pid | command [arg]...]"
+#define chrt_full_usage \
+ "manipulate real-time attributes of a process" \
+ "\n\nOptions:\n" \
+ " -p operate on pid\n" \
+ " -r set scheduling policy to SCHED_RR\n" \
+ " -f set scheduling policy to SCHED_FIFO\n" \
+ " -o set scheduling policy to SCHED_OTHER\n" \
+ " -m show min and max priorities"
+
+#define chrt_example_usage \
+ "$ chrt -r 4 sleep 900 ; x=$!\n" \
+ "$ chrt -f -p 3 $x\n" \
+ "You need CAP_SYS_NICE privileges to set scheduling attributes of a process"
+
#define cp_trivial_usage \
"[OPTION]... SOURCE DEST"
#define cp_full_usage \
diff --git a/miscutils/Config.in b/miscutils/Config.in
index 5afeb2a..a1ed243 100644
--- a/miscutils/Config.in
+++ b/miscutils/Config.in
@@ -19,6 +19,13 @@ config BBCONFIG
The bbconfig applet will print the config file with which
busybox was built.
+config CHRT
+ bool "chrt"
+ default n
+ help
+ manipulate real-time attributes of a process.
+ This requires sched_{g,s}etparam support in your libc.
+
config CROND
bool "crond"
default n
diff --git a/miscutils/Kbuild b/miscutils/Kbuild
index fe147d8..4551137 100644
--- a/miscutils/Kbuild
+++ b/miscutils/Kbuild
@@ -7,6 +7,7 @@
lib-y:=
lib-$(CONFIG_ADJTIMEX) += adjtimex.o
lib-$(CONFIG_BBCONFIG) += bbconfig.o
+lib-$(CONFIG_CHRT) += chrt.o
lib-$(CONFIG_CROND) += crond.o
lib-$(CONFIG_CRONTAB) += crontab.o
lib-$(CONFIG_DC) += dc.o
diff --git a/miscutils/chrt.c b/miscutils/chrt.c
new file mode 100644
index 0000000..75d77d5
--- /dev/null
+++ b/miscutils/chrt.c
@@ -0,0 +1,124 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * chrt - manipulate real-time attributes of a process
+ * Copyright (c) 2006-2007 Bernhard Fischer
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "busybox.h"
+#include <unistd.h>
+#include <sched.h>
+#include <getopt.h> /* optind */
+#ifndef _POSIX_PRIORITY_SCHEDULING
+#warning your system may be foobared
+#endif
+static const struct {
+ const int policy;
+ const char const name[12];
+} policies[] = {
+ {SCHED_OTHER, "SCHED_OTHER"},
+ {SCHED_FIFO, "SCHED_FIFO"},
+ {SCHED_RR, "SCHED_RR"}
+};
+
+static void show_min_max(int pol) {
+ const char *fmt = "%s min/max priority\t: %d/%d\n\0%s not supported?\n";
+ int max, min;
+ max = sched_get_priority_max(pol);
+ min = sched_get_priority_min(pol);
+ if (max >= 0 && min >= 0)
+ printf(fmt, policies[pol].name, min, max);
+ else {
+ fmt += 29;
+ printf(fmt, policies[pol].name);
+ }
+}
+
+#define OPT_m (1<<0)
+#define OPT_p (1<<1)
+#define OPT_r (1<<2)
+#define OPT_f (1<<3)
+#define OPT_o (1<<4)
+
+int chrt_main(int argc, char** argv);
+int chrt_main(int argc, char** argv)
+{
+ pid_t pid = 0;
+ unsigned opt;
+ struct sched_param sp;
+ char *p_opt = NULL, *priority = NULL;
+ const char *state = "current\0new";
+ int prio = 0, policy = SCHED_RR;
+
+ opt_complementary = "r--fo:f--ro:r--fo"; /* only one policy accepted */
+ opt = getopt32(argc, argv, "+mp:rfo", &p_opt);
+ if (opt & OPT_r)
+ policy = SCHED_RR;
+ if (opt & OPT_f)
+ policy = SCHED_FIFO;
+ if (opt & OPT_o)
+ policy = SCHED_OTHER;
+
+ if (opt & OPT_m) { /* print min/max */
+ show_min_max(SCHED_FIFO);
+ show_min_max(SCHED_RR);
+ show_min_max(SCHED_OTHER);
+ fflush_stdout_and_exit(EXIT_SUCCESS);
+ }
+ if (opt & OPT_p) {
+ if (argc == optind+1) { /* -p <priority> <pid> */
+ priority = p_opt;
+ p_opt = argv[optind];
+ }
+ argv += optind; /* me -p <arg> */
+ pid = xatoul_range(p_opt, 1, ULONG_MAX); /* -p <pid> */
+ } else {
+ argv += optind; /* me -p <arg> */
+ priority = *argv;
+ }
+ if (priority) {
+ /* from the manpage of sched_getscheduler:
+ [...] sched_priority can have a value
+ in the range 0 to 99.
+ [...] SCHED_OTHER or SCHED_BATCH must be assigned
+ the static priority 0. [...] SCHED_FIFO or
+ SCHED_RR can have a static priority in the range 1 to 99.
+ */
+ prio = xstrtol_range(priority, 0, policy == SCHED_OTHER
+ ? 0 : 1, 99);
+ }
+
+ if (opt & OPT_p) {
+ int pol = 0;
+print_rt_info:
+ pol = sched_getscheduler(pid);
+ if (pol < 0)
+ bb_perror_msg_and_die("failed to %cet pid %d's policy", 'g', pid);
+ printf("pid %d's %s scheduling policy: %s\n",
+ pid, state, policies[pol].name);
+ if (sched_getparam(pid, &sp))
+ bb_perror_msg_and_die("failed to get pid %d's attributes", pid);
+ printf("pid %d's %s scheduling priority: %d\n",
+ pid, state, sp.sched_priority);
+ if (!*argv) /* no new prio given or we did print already, done. */
+ return EXIT_SUCCESS;
+ }
+
+ sp.sched_priority = prio;
+ if (sched_setscheduler(pid, policy, &sp) < 0)
+ bb_perror_msg_and_die("failed to %cet pid %d's policy", 's', pid);
+ if (opt & OPT_p) {
+ state += 8;
+ ++argv;
+ goto print_rt_info;
+ }
+ ++argv;
+ BB_EXECVP(*argv, argv);
+ bb_perror_msg_and_die("%s", *argv);
+}
+#undef OPT_p
+#undef OPT_r
+#undef OPT_f
+#undef OPT_o
+#undef OPT_m
diff --git a/scripts/defconfig b/scripts/defconfig
index a3e59c8..178db1d 100644
--- a/scripts/defconfig
+++ b/scripts/defconfig
@@ -454,6 +454,7 @@ CONFIG_FEATURE_MOUNT_LOOP=y
#
CONFIG_ADJTIMEX=y
# CONFIG_BBCONFIG is not set
+CONFIG_CHRT=y
CONFIG_CROND=y
# CONFIG_DEBUG_CROND_OPTION is not set
CONFIG_FEATURE_CROND_CALL_SENDMAIL=y