129 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			129 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* vi: set sw=4 ts=4: */
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| /*
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|  * renice implementation for busybox
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|  *
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|  * Copyright (C) 2005  Manuel Novoa III  <mjn3@codepoet.org>
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|  *
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|  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
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|  */
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| 
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| /* Notes:
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|  *   Setting an absolute priority was obsoleted in SUSv2 and removed
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|  *   in SUSv3.  However, the common linux version of renice does
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|  *   absolute and not relative.  So we'll continue supporting absolute,
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|  *   although the stdout logging has been removed since both SUSv2 and
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|  *   SUSv3 specify that stdout isn't used.
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|  *
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|  *   This version is lenient in that it doesn't require any IDs.  The
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|  *   options -p, -g, and -u are treated as mode switches for the
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|  *   following IDs (if any).  Multiple switches are allowed.
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|  */
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| 
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| #include "libbb.h"
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| #include <sys/resource.h>
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| 
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| void BUG_bad_PRIO_PROCESS(void);
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| void BUG_bad_PRIO_PGRP(void);
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| void BUG_bad_PRIO_USER(void);
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| 
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| int renice_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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| int renice_main(int argc, char **argv)
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| {
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| 	static const char Xetpriority_msg[] ALIGN1 = "%cetpriority";
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| 
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| 	int retval = EXIT_SUCCESS;
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| 	int which = PRIO_PROCESS;	/* Default 'which' value. */
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| 	int use_relative = 0;
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| 	int adjustment, new_priority;
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| 	unsigned who;
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| 	char *arg;
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| 
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| 	/* Yes, they are not #defines in glibc 2.4! #if won't work */
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| 	if (PRIO_PROCESS < CHAR_MIN || PRIO_PROCESS > CHAR_MAX)
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| 		BUG_bad_PRIO_PROCESS();
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| 	if (PRIO_PGRP < CHAR_MIN || PRIO_PGRP > CHAR_MAX)
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| 		BUG_bad_PRIO_PGRP();
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| 	if (PRIO_USER < CHAR_MIN || PRIO_USER > CHAR_MAX)
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| 		BUG_bad_PRIO_USER();
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| 
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| 	arg = *++argv;
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| 
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| 	/* Check if we are using a relative adjustment. */
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| 	if (arg && arg[0] == '-' && arg[1] == 'n') {
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| 		use_relative = 1;
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| 		if (!arg[2])
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| 			arg = *++argv;
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| 		else
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| 			arg += 2;
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| 	}
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| 
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| 	if (!arg) {				/* No args?  Then show usage. */
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| 		bb_show_usage();
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| 	}
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| 
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| 	/* Get the priority adjustment (absolute or relative). */
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| 	adjustment = xatoi_range(arg, INT_MIN/2, INT_MAX/2);
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| 
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| 	while ((arg = *++argv) != NULL) {
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| 		/* Check for a mode switch. */
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| 		if (arg[0] == '-' && arg[1]) {
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| 			static const char opts[] ALIGN1 = {
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| 				'p', 'g', 'u', 0, PRIO_PROCESS, PRIO_PGRP, PRIO_USER
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| 			};
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| 			const char *p = strchr(opts, arg[1]);
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| 			if (p) {
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| 				which = p[4];
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| 				if (!arg[2])
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| 					continue;
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| 				arg += 2;
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| 			}
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| 		}
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| 
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| 		/* Process an ID arg. */
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| 		if (which == PRIO_USER) {
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| 			struct passwd *p;
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| 			p = getpwnam(arg);
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| 			if (!p) {
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| 				bb_error_msg("unknown user: %s", arg);
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| 				goto HAD_ERROR;
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| 			}
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| 			who = p->pw_uid;
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| 		} else {
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| 			who = bb_strtou(arg, NULL, 10);
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| 			if (errno) {
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| 				bb_error_msg("bad value: %s", arg);
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| 				goto HAD_ERROR;
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| 			}
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| 		}
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| 
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| 		/* Get priority to use, and set it. */
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| 		if (use_relative) {
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| 			int old_priority;
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| 
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| 			errno = 0;	 /* Needed for getpriority error detection. */
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| 			old_priority = getpriority(which, who);
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| 			if (errno) {
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| 				bb_perror_msg(Xetpriority_msg, 'g');
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| 				goto HAD_ERROR;
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| 			}
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| 
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| 			new_priority = old_priority + adjustment;
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| 		} else {
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| 			new_priority = adjustment;
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| 		}
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| 
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| 		if (setpriority(which, who, new_priority) == 0) {
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| 			continue;
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| 		}
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| 
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| 		bb_perror_msg(Xetpriority_msg, 's');
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|  HAD_ERROR:
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| 		retval = EXIT_FAILURE;
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| 	}
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| 
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| 	/* No need to check for errors outputing to stderr since, if it
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| 	 * was used, the HAD_ERROR label was reached and retval was set. */
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| 
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| 	return retval;
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| }
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