The Go Programming Language

Text file src/lib9/await.c

     1	/*
     2	Plan 9 from User Space src/lib9/await.c
     3	http://code.swtch.com/plan9port/src/tip/src/lib9/await.c
     4	
     5	Copyright 2001-2007 Russ Cox.  All Rights Reserved.
     6	Portions Copyright 2009 The Go Authors.  All Rights Reserved.
     7	
     8	Permission is hereby granted, free of charge, to any person obtaining a copy
     9	of this software and associated documentation files (the "Software"), to deal
    10	in the Software without restriction, including without limitation the rights
    11	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    12	copies of the Software, and to permit persons to whom the Software is
    13	furnished to do so, subject to the following conditions:
    14	
    15	The above copyright notice and this permission notice shall be included in
    16	all copies or substantial portions of the Software.
    17	
    18	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    19	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    20	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    21	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    22	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    23	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    24	THE SOFTWARE.
    25	*/
    26	
    27	#define NOPLAN9DEFINES
    28	#include <u.h>
    29	#include <libc.h>
    30	
    31	#include <signal.h>
    32	#include <sys/types.h>
    33	#include <sys/wait.h>
    34	#include <sys/time.h>
    35	#include <sys/resource.h>
    36	
    37	#ifndef WCOREDUMP	/* not on Mac OS X Tiger */
    38	#define WCOREDUMP(status) 0
    39	#endif
    40	
    41	static struct {
    42		int sig;
    43		char *str;
    44	} tab[] = {
    45		SIGHUP,		"hangup",
    46		SIGINT,		"interrupt",
    47		SIGQUIT,		"quit",
    48		SIGILL,		"sys: illegal instruction",
    49		SIGTRAP,		"sys: breakpoint",
    50		SIGABRT,		"sys: abort",
    51	#ifdef SIGEMT
    52		SIGEMT,		"sys: emulate instruction executed",
    53	#endif
    54		SIGFPE,		"sys: fp: trap",
    55		SIGKILL,		"sys: kill",
    56		SIGBUS,		"sys: bus error",
    57		SIGSEGV,		"sys: segmentation violation",
    58		SIGALRM,		"alarm",
    59		SIGTERM,		"kill",
    60		SIGURG,		"sys: urgent condition on socket",
    61		SIGSTOP,		"sys: stop",
    62		SIGTSTP,		"sys: tstp",
    63		SIGCONT,		"sys: cont",
    64		SIGCHLD,		"sys: child",
    65		SIGTTIN,		"sys: ttin",
    66		SIGTTOU,		"sys: ttou",
    67	#ifdef SIGIO	/* not on Mac OS X Tiger */
    68		SIGIO,		"sys: i/o possible on fd",
    69	#endif
    70		SIGXCPU,		"sys: cpu time limit exceeded",
    71		SIGXFSZ,		"sys: file size limit exceeded",
    72		SIGVTALRM,	"sys: virtual time alarm",
    73		SIGPROF,		"sys: profiling timer alarm",
    74	#ifdef SIGWINCH	/* not on Mac OS X Tiger */
    75		SIGWINCH,	"sys: window size change",
    76	#endif
    77	#ifdef SIGINFO
    78		SIGINFO,		"sys: status request",
    79	#endif
    80		SIGUSR1,		"sys: usr1",
    81		SIGUSR2,		"sys: usr2",
    82		SIGPIPE,		"sys: write on closed pipe",
    83	};
    84	
    85	char*
    86	_p9sigstr(int sig, char *tmp)
    87	{
    88		int i;
    89	
    90		for(i=0; i<nelem(tab); i++)
    91			if(tab[i].sig == sig)
    92				return tab[i].str;
    93		if(tmp == nil)
    94			return nil;
    95		sprint(tmp, "sys: signal %d", sig);
    96		return tmp;
    97	}
    98	
    99	int
   100	_p9strsig(char *s)
   101	{
   102		int i;
   103	
   104		for(i=0; i<nelem(tab); i++)
   105			if(strcmp(s, tab[i].str) == 0)
   106				return tab[i].sig;
   107		return 0;
   108	}
   109	
   110	static Waitmsg*
   111	_wait(int pid4, int opt)
   112	{
   113		int pid, status, cd;
   114		struct rusage ru;
   115		char tmp[64];
   116		ulong u, s;
   117		Waitmsg *w;
   118	
   119		w = malloc(sizeof *w + 200);
   120		if(w == nil)
   121			return nil;
   122		memset(w, 0, sizeof *w);
   123		w->msg = (char*)&w[1];
   124	
   125		for(;;){
   126			/* On Linux, pid==-1 means anyone; on SunOS, it's pid==0. */
   127			if(pid4 == -1)
   128				pid = wait3(&status, opt, &ru);
   129			else
   130				pid = wait4(pid4, &status, opt, &ru);
   131			if(pid <= 0) {
   132				free(w);
   133				return nil;
   134			}
   135			u = ru.ru_utime.tv_sec*1000+((ru.ru_utime.tv_usec+500)/1000);
   136			s = ru.ru_stime.tv_sec*1000+((ru.ru_stime.tv_usec+500)/1000);
   137			w->pid = pid;
   138			w->time[0] = u;
   139			w->time[1] = s;
   140			w->time[2] = u+s;
   141			if(WIFEXITED(status)){
   142				if(status)
   143					sprint(w->msg, "%d", status);
   144				return w;
   145			}
   146			if(WIFSIGNALED(status)){
   147				cd = WCOREDUMP(status);
   148				sprint(w->msg, "signal: %s", _p9sigstr(WTERMSIG(status), tmp));
   149				if(cd)
   150					strcat(w->msg, " (core dumped)");
   151				return w;
   152			}
   153		}
   154	}
   155	
   156	Waitmsg*
   157	p9wait(void)
   158	{
   159		return _wait(-1, 0);
   160	}
   161	
   162	Waitmsg*
   163	p9waitfor(int pid)
   164	{
   165		return _wait(pid, 0);
   166	}
   167	
   168	Waitmsg*
   169	p9waitnohang(void)
   170	{
   171		return _wait(-1, WNOHANG);
   172	}
   173	
   174	int
   175	p9waitpid(void)
   176	{
   177		int status;
   178		return wait(&status);
   179	}

release.r60.3. Except as noted, this content is licensed under a Creative Commons Attribution 3.0 License.