--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libiberty/strsignal.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,610 @@
+/* Extended support for using signal values.
+   Written by Fred Fish.  fnf@cygnus.com
+   This file is in the public domain.  */
+
+#include "config.h"
+#include "ansidecl.h"
+#include "libiberty.h"
+
+/* We need to declare sys_siglist, because even if the system provides
+   it we can't assume that it is declared in <signal.h> (for example,
+   SunOS provides sys_siglist, but it does not declare it in any
+   header file).  However, we can't declare sys_siglist portably,
+   because on some systems it is declared with const and on some
+   systems it is declared without const.  If we were using autoconf,
+   we could work out the right declaration.  Until, then we just
+   ignore any declaration in the system header files, and always
+   declare it ourselves.  With luck, this will always work.  */
+#define sys_siglist no_such_symbol
+#define sys_nsig sys_nsig__no_such_symbol
+
+#include <stdio.h>
+#include <signal.h>
+
+/*  Routines imported from standard C runtime libraries. */
+
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#else
+extern PTR malloc ();
+#endif
+
+#ifdef HAVE_STRING_H
+#include <string.h>
+#else
+extern PTR memset ();
+#endif
+
+/* Undefine the macro we used to hide the definition of sys_siglist
+   found in the system header files.  */
+#undef sys_siglist
+#undef sys_nsig
+
+#ifndef NULL
+#  define NULL (void *) 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b) ((a) > (b) ? (a) : (b))
+#endif
+
+static void init_signal_tables (void);
+
+/* Translation table for signal values.
+
+   Note that this table is generally only accessed when it is used at runtime
+   to initialize signal name and message tables that are indexed by signal
+   value.
+
+   Not all of these signals will exist on all systems.  This table is the only
+   thing that should have to be updated as new signal numbers are introduced.
+   It's sort of ugly, but at least its portable. */
+
+struct signal_info
+{
+  const int value;		/* The numeric value from <signal.h> */
+  const char *const name;	/* The equivalent symbolic value */
+#ifndef HAVE_SYS_SIGLIST
+  const char *const msg;	/* Short message about this value */
+#endif
+};
+
+#ifndef HAVE_SYS_SIGLIST
+#   define ENTRY(value, name, msg)	{value, name, msg}
+#else
+#   define ENTRY(value, name, msg)	{value, name}
+#endif
+
+static const struct signal_info signal_table[] =
+{
+#if defined (SIGHUP)
+  ENTRY(SIGHUP, "SIGHUP", "Hangup"),
+#endif
+#if defined (SIGINT)
+  ENTRY(SIGINT, "SIGINT", "Interrupt"),
+#endif
+#if defined (SIGQUIT)
+  ENTRY(SIGQUIT, "SIGQUIT", "Quit"),
+#endif
+#if defined (SIGILL)
+  ENTRY(SIGILL, "SIGILL", "Illegal instruction"),
+#endif
+#if defined (SIGTRAP)
+  ENTRY(SIGTRAP, "SIGTRAP", "Trace/breakpoint trap"),
+#endif
+/* Put SIGIOT before SIGABRT, so that if SIGIOT==SIGABRT then SIGABRT
+   overrides SIGIOT.  SIGABRT is in ANSI and POSIX.1, and SIGIOT isn't. */
+#if defined (SIGIOT)
+  ENTRY(SIGIOT, "SIGIOT", "IOT trap"),
+#endif
+#if defined (SIGABRT)
+  ENTRY(SIGABRT, "SIGABRT", "Aborted"),
+#endif
+#if defined (SIGEMT)
+  ENTRY(SIGEMT, "SIGEMT", "Emulation trap"),
+#endif
+#if defined (SIGFPE)
+  ENTRY(SIGFPE, "SIGFPE", "Arithmetic exception"),
+#endif
+#if defined (SIGKILL)
+  ENTRY(SIGKILL, "SIGKILL", "Killed"),
+#endif
+#if defined (SIGBUS)
+  ENTRY(SIGBUS, "SIGBUS", "Bus error"),
+#endif
+#if defined (SIGSEGV)
+  ENTRY(SIGSEGV, "SIGSEGV", "Segmentation fault"),
+#endif
+#if defined (SIGSYS)
+  ENTRY(SIGSYS, "SIGSYS", "Bad system call"),
+#endif
+#if defined (SIGPIPE)
+  ENTRY(SIGPIPE, "SIGPIPE", "Broken pipe"),
+#endif
+#if defined (SIGALRM)
+  ENTRY(SIGALRM, "SIGALRM", "Alarm clock"),
+#endif
+#if defined (SIGTERM)
+  ENTRY(SIGTERM, "SIGTERM", "Terminated"),
+#endif
+#if defined (SIGUSR1)
+  ENTRY(SIGUSR1, "SIGUSR1", "User defined signal 1"),
+#endif
+#if defined (SIGUSR2)
+  ENTRY(SIGUSR2, "SIGUSR2", "User defined signal 2"),
+#endif
+/* Put SIGCLD before SIGCHLD, so that if SIGCLD==SIGCHLD then SIGCHLD
+   overrides SIGCLD.  SIGCHLD is in POXIX.1 */
+#if defined (SIGCLD)
+  ENTRY(SIGCLD, "SIGCLD", "Child status changed"),
+#endif
+#if defined (SIGCHLD)
+  ENTRY(SIGCHLD, "SIGCHLD", "Child status changed"),
+#endif
+#if defined (SIGPWR)
+  ENTRY(SIGPWR, "SIGPWR", "Power fail/restart"),
+#endif
+#if defined (SIGWINCH)
+  ENTRY(SIGWINCH, "SIGWINCH", "Window size changed"),
+#endif
+#if defined (SIGURG)
+  ENTRY(SIGURG, "SIGURG", "Urgent I/O condition"),
+#endif
+#if defined (SIGIO)
+  /* "I/O pending" has also been suggested, but is misleading since the
+     signal only happens when the process has asked for it, not everytime
+     I/O is pending. */
+  ENTRY(SIGIO, "SIGIO", "I/O possible"),
+#endif
+#if defined (SIGPOLL)
+  ENTRY(SIGPOLL, "SIGPOLL", "Pollable event occurred"),
+#endif
+#if defined (SIGSTOP)
+  ENTRY(SIGSTOP, "SIGSTOP", "Stopped (signal)"),
+#endif
+#if defined (SIGTSTP)
+  ENTRY(SIGTSTP, "SIGTSTP", "Stopped (user)"),
+#endif
+#if defined (SIGCONT)
+  ENTRY(SIGCONT, "SIGCONT", "Continued"),
+#endif
+#if defined (SIGTTIN)
+  ENTRY(SIGTTIN, "SIGTTIN", "Stopped (tty input)"),
+#endif
+#if defined (SIGTTOU)
+  ENTRY(SIGTTOU, "SIGTTOU", "Stopped (tty output)"),
+#endif
+#if defined (SIGVTALRM)
+  ENTRY(SIGVTALRM, "SIGVTALRM", "Virtual timer expired"),
+#endif
+#if defined (SIGPROF)
+  ENTRY(SIGPROF, "SIGPROF", "Profiling timer expired"),
+#endif
+#if defined (SIGXCPU)
+  ENTRY(SIGXCPU, "SIGXCPU", "CPU time limit exceeded"),
+#endif
+#if defined (SIGXFSZ)
+  ENTRY(SIGXFSZ, "SIGXFSZ", "File size limit exceeded"),
+#endif
+#if defined (SIGWIND)
+  ENTRY(SIGWIND, "SIGWIND", "SIGWIND"),
+#endif
+#if defined (SIGPHONE)
+  ENTRY(SIGPHONE, "SIGPHONE", "SIGPHONE"),
+#endif
+#if defined (SIGLOST)
+  ENTRY(SIGLOST, "SIGLOST", "Resource lost"),
+#endif
+#if defined (SIGWAITING)
+  ENTRY(SIGWAITING, "SIGWAITING", "Process's LWPs are blocked"),
+#endif
+#if defined (SIGLWP)
+  ENTRY(SIGLWP, "SIGLWP", "Signal LWP"),
+#endif
+#if defined (SIGDANGER)
+  ENTRY(SIGDANGER, "SIGDANGER", "Swap space dangerously low"),
+#endif
+#if defined (SIGGRANT)
+  ENTRY(SIGGRANT, "SIGGRANT", "Monitor mode granted"),
+#endif
+#if defined (SIGRETRACT)
+  ENTRY(SIGRETRACT, "SIGRETRACT", "Need to relinguish monitor mode"),
+#endif
+#if defined (SIGMSG)
+  ENTRY(SIGMSG, "SIGMSG", "Monitor mode data available"),
+#endif
+#if defined (SIGSOUND)
+  ENTRY(SIGSOUND, "SIGSOUND", "Sound completed"),
+#endif
+#if defined (SIGSAK)
+  ENTRY(SIGSAK, "SIGSAK", "Secure attention"),
+#endif
+  ENTRY(0, NULL, NULL)
+};
+
+/* Translation table allocated and initialized at runtime.  Indexed by the
+   signal value to find the equivalent symbolic value. */
+
+static const char **signal_names;
+static int num_signal_names = 0;
+
+/* Translation table allocated and initialized at runtime, if it does not
+   already exist in the host environment.  Indexed by the signal value to find
+   the descriptive string.
+
+   We don't export it for use in other modules because even though it has the
+   same name, it differs from other implementations in that it is dynamically
+   initialized rather than statically initialized. */
+
+#ifndef HAVE_SYS_SIGLIST
+
+static int sys_nsig;
+static const char **sys_siglist;
+
+#else
+
+#ifdef NSIG
+static int sys_nsig = NSIG;
+#else
+#ifdef _NSIG
+static int sys_nsig = _NSIG;
+#endif
+#endif
+extern const char * const sys_siglist[];
+
+#endif
+
+
+/*
+
+NAME
+
+	init_signal_tables -- initialize the name and message tables
+
+SYNOPSIS
+
+	static void init_signal_tables ();
+
+DESCRIPTION
+
+	Using the signal_table, which is initialized at compile time, generate
+	the signal_names and the sys_siglist (if needed) tables, which are
+	indexed at runtime by a specific signal value.
+
+BUGS
+
+	The initialization of the tables may fail under low memory conditions,
+	in which case we don't do anything particularly useful, but we don't
+	bomb either.  Who knows, it might succeed at a later point if we free
+	some memory in the meantime.  In any case, the other routines know
+	how to deal with lack of a table after trying to initialize it.  This
+	may or may not be considered to be a bug, that we don't specifically
+	warn about this particular failure mode.
+
+*/
+
+static void
+init_signal_tables (void)
+{
+  const struct signal_info *eip;
+  int nbytes;
+
+  /* If we haven't already scanned the signal_table once to find the maximum
+     signal value, then go find it now. */
+
+  if (num_signal_names == 0)
+    {
+      for (eip = signal_table; eip -> name != NULL; eip++)
+	{
+	  if (eip -> value >= num_signal_names)
+	    {
+	      num_signal_names = eip -> value + 1;
+	    }
+	}
+    }
+
+  /* Now attempt to allocate the signal_names table, zero it out, and then
+     initialize it from the statically initialized signal_table. */
+
+  if (signal_names == NULL)
+    {
+      nbytes = num_signal_names * sizeof (char *);
+      if ((signal_names = (const char **) malloc (nbytes)) != NULL)
+	{
+	  memset (signal_names, 0, nbytes);
+	  for (eip = signal_table; eip -> name != NULL; eip++)
+	    {
+	      signal_names[eip -> value] = eip -> name;
+	    }
+	}
+    }
+
+#ifndef HAVE_SYS_SIGLIST
+
+  /* Now attempt to allocate the sys_siglist table, zero it out, and then
+     initialize it from the statically initialized signal_table. */
+
+  if (sys_siglist == NULL)
+    {
+      nbytes = num_signal_names * sizeof (char *);
+      if ((sys_siglist = (const char **) malloc (nbytes)) != NULL)
+	{
+	  memset (sys_siglist, 0, nbytes);
+	  sys_nsig = num_signal_names;
+	  for (eip = signal_table; eip -> name != NULL; eip++)
+	    {
+	      sys_siglist[eip -> value] = eip -> msg;
+	    }
+	}
+    }
+
+#endif
+
+}
+
+
+/*
+
+@deftypefn Extension int signo_max (void)
+
+Returns the maximum signal value for which a corresponding symbolic
+name or message is available.  Note that in the case where we use the
+@code{sys_siglist} supplied by the system, it is possible for there to
+be more symbolic names than messages, or vice versa.  In fact, the
+manual page for @code{psignal(3b)} explicitly warns that one should
+check the size of the table (@code{NSIG}) before indexing it, since
+new signal codes may be added to the system before they are added to
+the table.  Thus @code{NSIG} might be smaller than value implied by
+the largest signo value defined in @code{<signal.h>}.
+
+We return the maximum value that can be used to obtain a meaningful
+symbolic name or message.
+
+@end deftypefn
+
+*/
+
+int
+signo_max (void)
+{
+  int maxsize;
+
+  if (signal_names == NULL)
+    {
+      init_signal_tables ();
+    }
+  maxsize = MAX (sys_nsig, num_signal_names);
+  return (maxsize - 1);
+}
+
+
+/*
+
+@deftypefn Supplemental {const char *} strsignal (int @var{signo})
+
+Maps an signal number to an signal message string, the contents of
+which are implementation defined.  On systems which have the external
+variable @code{sys_siglist}, these strings will be the same as the
+ones used by @code{psignal()}.
+
+If the supplied signal number is within the valid range of indices for
+the @code{sys_siglist}, but no message is available for the particular
+signal number, then returns the string @samp{Signal @var{num}}, where
+@var{num} is the signal number.
+
+If the supplied signal number is not a valid index into
+@code{sys_siglist}, returns @code{NULL}.
+
+The returned string is only guaranteed to be valid only until the next
+call to @code{strsignal}.
+
+@end deftypefn
+
+*/
+
+#ifndef HAVE_STRSIGNAL
+
+char *
+strsignal (int signo)
+{
+  char *msg;
+  static char buf[32];
+
+#ifndef HAVE_SYS_SIGLIST
+
+  if (signal_names == NULL)
+    {
+      init_signal_tables ();
+    }
+
+#endif
+
+  if ((signo < 0) || (signo >= sys_nsig))
+    {
+      /* Out of range, just return NULL */
+      msg = NULL;
+    }
+  else if ((sys_siglist == NULL) || (sys_siglist[signo] == NULL))
+    {
+      /* In range, but no sys_siglist or no entry at this index. */
+      sprintf (buf, "Signal %d", signo);
+      msg = buf;
+    }
+  else
+    {
+      /* In range, and a valid message.  Just return the message.  We
+	 can safely cast away const, since POSIX says the user must
+	 not modify the result.	 */
+      msg = (char *) sys_siglist[signo];
+    }
+
+  return (msg);
+}
+
+#endif /* ! HAVE_STRSIGNAL */
+
+/*
+
+@deftypefn Extension {const char*} strsigno (int @var{signo})
+
+Given an signal number, returns a pointer to a string containing the
+symbolic name of that signal number, as found in @code{<signal.h>}.
+
+If the supplied signal number is within the valid range of indices for
+symbolic names, but no name is available for the particular signal
+number, then returns the string @samp{Signal @var{num}}, where
+@var{num} is the signal number.
+
+If the supplied signal number is not within the range of valid
+indices, then returns @code{NULL}.
+
+The contents of the location pointed to are only guaranteed to be
+valid until the next call to @code{strsigno}.
+
+@end deftypefn
+
+*/
+
+const char *
+strsigno (int signo)
+{
+  const char *name;
+  static char buf[32];
+
+  if (signal_names == NULL)
+    {
+      init_signal_tables ();
+    }
+
+  if ((signo < 0) || (signo >= num_signal_names))
+    {
+      /* Out of range, just return NULL */
+      name = NULL;
+    }
+  else if ((signal_names == NULL) || (signal_names[signo] == NULL))
+    {
+      /* In range, but no signal_names or no entry at this index. */
+      sprintf (buf, "Signal %d", signo);
+      name = (const char *) buf;
+    }
+  else
+    {
+      /* In range, and a valid name.  Just return the name. */
+      name = signal_names[signo];
+    }
+
+  return (name);
+}
+
+
+/*
+
+@deftypefn Extension int strtosigno (const char *@var{name})
+
+Given the symbolic name of a signal, map it to a signal number.  If no
+translation is found, returns 0.
+
+@end deftypefn
+
+*/
+
+int
+strtosigno (const char *name)
+{
+  int signo = 0;
+
+  if (name != NULL)
+    {
+      if (signal_names == NULL)
+	{
+	  init_signal_tables ();
+	}
+      for (signo = 0; signo < num_signal_names; signo++)
+	{
+	  if ((signal_names[signo] != NULL) &&
+	      (strcmp (name, signal_names[signo]) == 0))
+	    {
+	      break;
+	    }
+	}
+      if (signo == num_signal_names)
+	{
+	  signo = 0;
+	}
+    }
+  return (signo);
+}
+
+
+/*
+
+@deftypefn Supplemental void psignal (int @var{signo}, char *@var{message})
+
+Print @var{message} to the standard error, followed by a colon,
+followed by the description of the signal specified by @var{signo},
+followed by a newline.
+
+@end deftypefn
+
+*/
+
+#ifndef HAVE_PSIGNAL
+
+void
+psignal (int signo, char *message)
+{
+  if (signal_names == NULL)
+    {
+      init_signal_tables ();
+    }
+  if ((signo <= 0) || (signo >= sys_nsig))
+    {
+      fprintf (stderr, "%s: unknown signal\n", message);
+    }
+  else
+    {
+      fprintf (stderr, "%s: %s\n", message, sys_siglist[signo]);
+    }
+}
+
+#endif	/* ! HAVE_PSIGNAL */
+
+
+/* A simple little main that does nothing but print all the signal translations
+   if MAIN is defined and this file is compiled and linked. */
+
+#ifdef MAIN
+
+#include <stdio.h>
+
+int
+main (void)
+{
+  int signo;
+  int maxsigno;
+  const char *name;
+  const char *msg;
+
+  maxsigno = signo_max ();
+  printf ("%d entries in names table.\n", num_signal_names);
+  printf ("%d entries in messages table.\n", sys_nsig);
+  printf ("%d is max useful index.\n", maxsigno);
+
+  /* Keep printing values until we get to the end of *both* tables, not
+     *either* table.  Note that knowing the maximum useful index does *not*
+     relieve us of the responsibility of testing the return pointer for
+     NULL. */
+
+  for (signo = 0; signo <= maxsigno; signo++)
+    {
+      name = strsigno (signo);
+      name = (name == NULL) ? "<NULL>" : name;
+      msg = strsignal (signo);
+      msg = (msg == NULL) ? "<NULL>" : msg;
+      printf ("%-4d%-18s%s\n", signo, name, msg);
+    }
+
+  return 0;
+}
+
+#endif