1 /* vi: set sw=4 ts=4: */
2 /*
3  * Signal name/number conversion routines.
4  *
5  * Copyright 2006 Rob Landley <rob@landley.net>
6  *
7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8  */
9 //config:config FEATURE_RTMINMAX
10 //config:	bool "Support RTMIN[+n] and RTMAX[-n] signal names"
11 //config:	default y
12 //config:	help
13 //config:	Support RTMIN[+n] and RTMAX[-n] signal names
14 //config:	in kill, killall etc. This costs ~250 bytes.
15 //config:
16 //config:config FEATURE_RTMINMAX_USE_LIBC_DEFINITIONS
17 //config:	bool "Use the definitions of SIGRTMIN/SIGRTMAX provided by libc"
18 //config:	default y
19 //config:	depends on FEATURE_RTMINMAX
20 //config:	help
21 //config:	Some C libraries reserve a few real-time signals for internal
22 //config:	use, and adjust the values of SIGRTMIN/SIGRTMAX seen by
23 //config:	applications accordingly. Saying yes here means that a signal
24 //config:	name RTMIN+n will be interpreted according to the libc definition
25 //config:	of SIGRTMIN, and not the raw definition provided by the kernel.
26 //config:	This behavior matches "kill -l RTMIN+n" from bash.
27 
28 #include "libbb.h"
29 
30 /* Believe it or not, but some arches have more than 32 SIGs!
31  * HPPA: SIGSTKFLT == 36. */
32 
33 static const char signals[][7] ALIGN1 = {
34 	// SUSv3 says kill must support these, and specifies the numerical values,
35 	// http://www.opengroup.org/onlinepubs/009695399/utilities/kill.html
36 	// {0, "EXIT"}, {1, "HUP"}, {2, "INT"}, {3, "QUIT"},
37 	// {6, "ABRT"}, {9, "KILL"}, {14, "ALRM"}, {15, "TERM"}
38 	// And Posix adds the following:
39 	// {SIGILL, "ILL"}, {SIGTRAP, "TRAP"}, {SIGFPE, "FPE"}, {SIGUSR1, "USR1"},
40 	// {SIGSEGV, "SEGV"}, {SIGUSR2, "USR2"}, {SIGPIPE, "PIPE"}, {SIGCHLD, "CHLD"},
41 	// {SIGCONT, "CONT"}, {SIGSTOP, "STOP"}, {SIGTSTP, "TSTP"}, {SIGTTIN, "TTIN"},
42 	// {SIGTTOU, "TTOU"}
43 
44 	[0] = "EXIT",
45 #ifdef SIGHUP
46 	[SIGHUP   ] = "HUP",
47 #endif
48 #ifdef SIGINT
49 	[SIGINT   ] = "INT",
50 #endif
51 #ifdef SIGQUIT
52 	[SIGQUIT  ] = "QUIT",
53 #endif
54 #ifdef SIGILL
55 	[SIGILL   ] = "ILL",
56 #endif
57 #ifdef SIGTRAP
58 	[SIGTRAP  ] = "TRAP",
59 #endif
60 #ifdef SIGABRT
61 	[SIGABRT  ] = "ABRT",
62 #endif
63 #ifdef SIGBUS
64 	[SIGBUS   ] = "BUS",
65 #endif
66 #ifdef SIGFPE
67 	[SIGFPE   ] = "FPE",
68 #endif
69 #ifdef SIGKILL
70 	[SIGKILL  ] = "KILL",
71 #endif
72 #ifdef SIGUSR1
73 	[SIGUSR1  ] = "USR1",
74 #endif
75 #ifdef SIGSEGV
76 	[SIGSEGV  ] = "SEGV",
77 #endif
78 #ifdef SIGUSR2
79 	[SIGUSR2  ] = "USR2",
80 #endif
81 #ifdef SIGPIPE
82 	[SIGPIPE  ] = "PIPE",
83 #endif
84 #ifdef SIGALRM
85 	[SIGALRM  ] = "ALRM",
86 #endif
87 #ifdef SIGTERM
88 	[SIGTERM  ] = "TERM",
89 #endif
90 #ifdef SIGSTKFLT
91 	[SIGSTKFLT] = "STKFLT",
92 #endif
93 #ifdef SIGCHLD
94 	[SIGCHLD  ] = "CHLD",
95 #endif
96 #ifdef SIGCONT
97 	[SIGCONT  ] = "CONT",
98 #endif
99 #ifdef SIGSTOP
100 	[SIGSTOP  ] = "STOP",
101 #endif
102 #ifdef SIGTSTP
103 	[SIGTSTP  ] = "TSTP",
104 #endif
105 #ifdef SIGTTIN
106 	[SIGTTIN  ] = "TTIN",
107 #endif
108 #ifdef SIGTTOU
109 	[SIGTTOU  ] = "TTOU",
110 #endif
111 #ifdef SIGURG
112 	[SIGURG   ] = "URG",
113 #endif
114 #ifdef SIGXCPU
115 	[SIGXCPU  ] = "XCPU",
116 #endif
117 #ifdef SIGXFSZ
118 	[SIGXFSZ  ] = "XFSZ",
119 #endif
120 #ifdef SIGVTALRM
121 	[SIGVTALRM] = "VTALRM",
122 #endif
123 #ifdef SIGPROF
124 	[SIGPROF  ] = "PROF",
125 #endif
126 #ifdef SIGWINCH
127 	[SIGWINCH ] = "WINCH",
128 #endif
129 #ifdef SIGPOLL
130 	[SIGPOLL  ] = "POLL",
131 #endif
132 #ifdef SIGPWR
133 	[SIGPWR   ] = "PWR",
134 #endif
135 #ifdef SIGSYS
136 	[SIGSYS   ] = "SYS",
137 #endif
138 #if ENABLE_FEATURE_RTMINMAX && !ENABLE_FEATURE_RTMINMAX_USE_LIBC_DEFINITIONS
139 # ifdef __SIGRTMIN
140 	[__SIGRTMIN] = "RTMIN",
141 # endif
142 // This makes array about x2 bigger.
143 // More compact approach is to special-case SIGRTMAX in print_signames()
144 //# ifdef __SIGRTMAX
145 //	[__SIGRTMAX] = "RTMAX",
146 //# endif
147 #endif
148 };
149 
150 // Convert signal name to number.
151 
get_signum(const char * name)152 int FAST_FUNC get_signum(const char *name)
153 {
154 	unsigned i;
155 
156 	/* bb_strtou returns UINT_MAX on error. NSIG is smaller
157 	 * than UINT_MAX on any sane Unix. Hence no need
158 	 * to check errno after bb_strtou().
159 	 */
160 	i = bb_strtou(name, NULL, 10);
161 	if (i < NSIG) /* for shells, we allow 0 too */
162 		return i;
163 	if (strncasecmp(name, "SIG", 3) == 0)
164 		name += 3;
165 	for (i = 0; i < ARRAY_SIZE(signals); i++)
166 		if (strcasecmp(name, signals[i]) == 0)
167 			return i;
168 
169 #if ENABLE_DESKTOP
170 # if defined(SIGIOT) || defined(SIGIO)
171 	/* SIGIO[T] are aliased to other names,
172 	 * thus cannot be stored in the signals[] array.
173 	 * Need special code to recognize them */
174 	if ((name[0] | 0x20) == 'i' && (name[1] | 0x20) == 'o') {
175 #  ifdef SIGIO
176 		if (!name[2])
177 			return SIGIO;
178 #  endif
179 #  ifdef SIGIOT
180 		if ((name[2] | 0x20) == 't' && !name[3])
181 			return SIGIOT;
182 #  endif
183 	}
184 # endif
185 #endif
186 
187 #if ENABLE_FEATURE_RTMINMAX && defined(SIGRTMIN) && defined(SIGRTMAX)
188 	{
189 # if ENABLE_FEATURE_RTMINMAX_USE_LIBC_DEFINITIONS
190 		/* Use the libc provided values. */
191 		unsigned sigrtmin = SIGRTMIN;
192 		unsigned sigrtmax = SIGRTMAX;
193 # else
194 	/* Use the "raw" SIGRTMIN/MAX. Underscored names, if exist, provide
195 	 * them. If they don't exist, fall back to non-underscored ones: */
196 #  if !defined(__SIGRTMIN)
197 #   define __SIGRTMIN SIGRTMIN
198 #  endif
199 #  if !defined(__SIGRTMAX)
200 #   define __SIGRTMAX SIGRTMAX
201 #  endif
202 
203 #  define sigrtmin __SIGRTMIN
204 #  define sigrtmax __SIGRTMAX
205 # endif
206 		if (strncasecmp(name, "RTMIN", 5) == 0) {
207 			if (!name[5])
208 				return sigrtmin;
209 			if (name[5] == '+') {
210 				i = bb_strtou(name + 6, NULL, 10);
211 				if (i <= sigrtmax - sigrtmin)
212 					return sigrtmin + i;
213 			}
214 		}
215 		else if (strncasecmp(name, "RTMAX", 5) == 0) {
216 			if (!name[5])
217 				return sigrtmax;
218 			if (name[5] == '-') {
219 				i = bb_strtou(name + 6, NULL, 10);
220 				if (i <= sigrtmax - sigrtmin)
221 					return sigrtmax - i;
222 			}
223 		}
224 # undef sigrtmin
225 # undef sigrtmax
226 	}
227 #endif
228 
229 	return -1;
230 }
231 
232 // Convert signal number to name
233 
get_signame(int number)234 const char* FAST_FUNC get_signame(int number)
235 {
236 	if ((unsigned)number < ARRAY_SIZE(signals)) {
237 		if (signals[number][0]) /* if it's not an empty str */
238 			return signals[number];
239 	}
240 
241 	return itoa(number);
242 }
243 
244 
245 // Print the whole signal list
246 
print_signames(void)247 void FAST_FUNC print_signames(void)
248 {
249 	unsigned signo;
250 
251 	for (signo = 1; signo < ARRAY_SIZE(signals); signo++) {
252 		const char *name = signals[signo];
253 		if (name[0])
254 			printf("%2u) %s\n", signo, name);
255 	}
256 #if ENABLE_FEATURE_RTMINMAX
257 # if ENABLE_FEATURE_RTMINMAX_USE_LIBC_DEFINITIONS
258 #  if defined(SIGRTMIN) && defined(SIGRTMAX)
259 	printf("%2u) %s\n", SIGRTMIN, "RTMIN");
260 	printf("%2u) %s\n", SIGRTMAX, "RTMAX");
261 #  endif
262 # else
263 // __SIGRTMIN is included in signals[] array.
264 #  ifdef __SIGRTMAX
265 	printf("%2u) %s\n", __SIGRTMAX, "RTMAX");
266 #  endif
267 # endif
268 #endif
269 }
270