LXR busybox/libbb/u_signal

   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
  33static 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
 152int 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
 234const 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
 247void 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