1 files changed, 126 insertions, 0 deletions

diff --git a/procps/renice.c b/procps/renice.c
new file mode 100644
index 000000000..08e0dc264
--- /dev/null
+++ b/procps/renice.c
@@ -0,0 +1,126 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * renice implementation for busybox
+ *
+ * Copyright (C) 2005  Manuel Novoa III  <mjn3@codepoet.org>
+ *
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ */
+
+/* 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 "busybox.h"
+#include <sys/resource.h>
+
+void BUG_bad_PRIO_PROCESS(void);
+void BUG_bad_PRIO_PGRP(void);
+void BUG_bad_PRIO_USER(void);
+
+int renice_main(int argc, char **argv)
+{
+        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;
+
+        /* Yes, they are not #defines in glibc 2.4! #if won't work */
+        if (PRIO_PROCESS < CHAR_MIN || PRIO_PROCESS > CHAR_MAX)
+                BUG_bad_PRIO_PROCESS();
+        if (PRIO_PGRP < CHAR_MIN || PRIO_PGRP > CHAR_MAX)
+                BUG_bad_PRIO_PGRP();
+        if (PRIO_USER < CHAR_MIN || PRIO_USER > CHAR_MAX)
+                BUG_bad_PRIO_USER();
+
+        arg = *++argv;
+
+        /* Check if we are using a relative adjustment. */
+        if (arg && arg[0] == '-' && arg[1] == 'n') {
+                use_relative = 1;
+                if (!arg[2])
+                        arg = *++argv;
+                else
+                        arg += 2;
+        }
+
+        if (!arg) {                             /* No args?  Then show usage. */
+                bb_show_usage();
+        }
+
+        /* Get the priority adjustment (absolute or relative). */
+        adjustment = xatoi_range(arg, INT_MIN/2, INT_MAX/2);
+
+        while ((arg = *++argv) != NULL) {
+                /* Check for a mode switch. */
+                if (arg[0] == '-' && arg[1]) {
+                        static const char opts[]
+                                = { 'p', 'g', 'u', 0, PRIO_PROCESS, PRIO_PGRP, PRIO_USER };
+                        const char *p = strchr(opts, arg[1]);
+                        if (p) {
+                                which = p[4];
+                                if (!arg[2])
+                                        continue;
+                                arg += 2;
+                        }
+                }
+
+                /* Process an ID arg. */
+                if (which == PRIO_USER) {
+                        struct passwd *p;
+                        p = getpwnam(arg);
+                        if (!p) {
+                                bb_error_msg("unknown user: %s", arg);
+                                goto HAD_ERROR;
+                        }
+                        who = p->pw_uid;
+                } else {
+                        who = bb_strtou(arg, NULL, 10);
+                        if (errno) {
+                                bb_error_msg("bad value: %s", arg);
+                                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, 'g');
+                                goto HAD_ERROR;
+                        }
+
+                        new_priority = old_priority + adjustment;
+                } else {
+                        new_priority = adjustment;
+                }
+
+                if (setpriority(which, who, new_priority) == 0) {
+                        continue;
+                }
+
+                bb_perror_msg(Xetpriority_msg, 's');
+ HAD_ERROR:
+                retval = EXIT_FAILURE;
+        }
+
+        /* 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;
+}