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-rw-r--r--procps/renice.c132
1 files changed, 115 insertions, 17 deletions
diff --git a/procps/renice.c b/procps/renice.c
index a6f0820df..d4ce66d2e 100644
--- a/procps/renice.c
+++ b/procps/renice.c
@@ -1,8 +1,8 @@
+/* vi: set sw=4 ts=4: */
/*
- * Mini renice implementation for busybox
+ * renice implementation for busybox
*
- *
- * Copyright (C) 2000 Dave 'Kill a Cop' Cinege <dcinege@psychosis.com>
+ * Copyright (C) 2005 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
@@ -20,35 +20,133 @@
*
*/
+/* Notes:
+ * Setting an absolute priority was obsoleted in SUSv2 and removed
+ * in SUSv3. However, the common linux version of renice does
+ * absolute and not relative. So we'll continue supporting absolute,
+ * although the stdout logging has been removed since both SUSv2 and
+ * SUSv3 specify that stdout isn't used.
+ *
+ * This version is lenient in that it doesn't require any IDs. The
+ * options -p, -g, and -u are treated as mode switches for the
+ * following IDs (if any). Multiple switches are allowed.
+ */
+
#include <stdio.h>
-#include <errno.h>
#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <errno.h>
+#include <unistd.h>
#include <sys/time.h>
#include <sys/resource.h>
#include "busybox.h"
+#if (PRIO_PROCESS < CHAR_MIN) || (PRIO_PROCESS > CHAR_MAX)
+#error Assumption violated : PRIO_PROCESS value
+#endif
+#if (PRIO_PGRP < CHAR_MIN) || (PRIO_PGRP > CHAR_MAX)
+#error Assumption violated : PRIO_PGRP value
+#endif
+#if (PRIO_USER < CHAR_MIN) || (PRIO_USER > CHAR_MAX)
+#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;
+ }
-extern int renice_main(int argc, char **argv)
+ return s;
+}
+
+int renice_main(int argc, char **argv)
{
- int prio, status = EXIT_SUCCESS;
+ static const char Xetpriority_msg[] = "%d : %cetpriority";
+
+ int retval = EXIT_SUCCESS;
+ int which = PRIO_PROCESS; /* Default 'which' value. */
+ int use_relative = 0;
+ int adjustment, new_priority;
+ id_t who;
- if (argc < 3) bb_show_usage();
+ ++argv;
- prio = atoi(*++argv);
- if (prio > 20) prio = 20;
- if (prio < -20) prio = -20;
+ /* Check if we are using a relative adjustment. */
+ if (argv[0] && (argv[0][0] == '-') && (argv[0][1] == 'n') && !argv[0][2]) {
+ use_relative = 1;
+ ++argv;
+ }
+
+ if (!*argv) { /* No args? Then show usage. */
+ bb_show_usage();
+ }
+
+ /* Get the priority adjustment (absolute or relative). */
+ adjustment = bb_xgetlarg(*argv, 10, INT_MIN, INT_MAX);
while (*++argv) {
- int ps = atoi(*argv);
- int oldp = getpriority(PRIO_PROCESS, ps);
+ /* Check for a mode switch. */
+ if ((argv[0][0] == '-') && argv[0][1] && !argv[0][2]) {
+ static const char opts[]
+ = { 'p', 'g', 'u', 0, PRIO_PROCESS, PRIO_PGRP, PRIO_USER };
+ const char *p;
+ if ((p = strchr(opts, argv[0][1]))) {
+ which = p[4];
+ continue;
+ }
+ }
- if (setpriority(PRIO_PROCESS, ps, prio) == 0) {
- printf("%d: old priority %d, new priority %d\n", ps, oldp, prio );
+ /* Process an ID arg. */
+ if (which == PRIO_USER) {
+ struct passwd *p;
+ if (!(p = getpwnam(*argv))) {
+ bb_error_msg("unknown user: %s", *argv);
+ goto HAD_ERROR;
+ }
+ who = p->pw_uid;
} else {
- bb_perror_msg("%d: setpriority", ps);
- status = EXIT_FAILURE;
+ char *e;
+ errno = 0;
+ who = strtoul(*argv, &e, 10);
+ if (*e || (*argv == e) || errno) {
+ bb_error_msg("bad value: %s", *argv);
+ goto HAD_ERROR;
+ }
}
+
+ /* Get priority to use, and set it. */
+ if (use_relative) {
+ int old_priority;
+
+ errno = 0; /* Needed for getpriority error detection. */
+ old_priority = getpriority(which, who);
+ if (errno) {
+ bb_perror_msg(Xetpriority_msg, who, 'g');
+ goto HAD_ERROR;
+ }
+
+ new_priority = int_add_no_wrap(old_priority, adjustment);
+ } else {
+ new_priority = adjustment;
+ }
+
+ if (setpriority(which, who, new_priority) == 0) {
+ continue;
+ }
+
+ bb_perror_msg(Xetpriority_msg, who, 's');
+ HAD_ERROR:
+ retval = EXIT_FAILURE;
}
- return status;
+ /* No need to check for errors outputing to stderr since, if it
+ * was used, the HAD_ERROR label was reached and retval was set. */
+
+ return retval;
}