github.com/rohankumardubey/syslog-redirector-golang@v0.0.0-20140320174030-4859f03d829a/src/lib9/await.c (about)

     1  // +build !windows
     2  
     3  /*
     4  Plan 9 from User Space src/lib9/await.c
     5  http://code.swtch.com/plan9port/src/tip/src/lib9/await.c
     6  
     7  Copyright 2001-2007 Russ Cox.  All Rights Reserved.
     8  Portions Copyright 2009 The Go Authors.  All Rights Reserved.
     9  
    10  Permission is hereby granted, free of charge, to any person obtaining a copy
    11  of this software and associated documentation files (the "Software"), to deal
    12  in the Software without restriction, including without limitation the rights
    13  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    14  copies of the Software, and to permit persons to whom the Software is
    15  furnished to do so, subject to the following conditions:
    16  
    17  The above copyright notice and this permission notice shall be included in
    18  all copies or substantial portions of the Software.
    19  
    20  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    21  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    22  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    23  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    24  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    25  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    26  THE SOFTWARE.
    27  */
    28  
    29  #define NOPLAN9DEFINES
    30  #include <u.h>
    31  #include <libc.h>
    32  
    33  #include <signal.h>
    34  #include <sys/types.h>
    35  #include <sys/wait.h>
    36  #include <sys/time.h>
    37  #include <sys/resource.h>
    38  
    39  #ifndef WCOREDUMP	/* not on Mac OS X Tiger */
    40  #define WCOREDUMP(status) 0
    41  #endif
    42  
    43  static struct {
    44  	int sig;
    45  	char *str;
    46  } tab[] = {
    47  	SIGHUP,		"hangup",
    48  	SIGINT,		"interrupt",
    49  	SIGQUIT,		"quit",
    50  	SIGILL,		"sys: illegal instruction",
    51  	SIGTRAP,		"sys: breakpoint",
    52  	SIGABRT,		"sys: abort",
    53  #ifdef SIGEMT
    54  	SIGEMT,		"sys: emulate instruction executed",
    55  #endif
    56  	SIGFPE,		"sys: fp: trap",
    57  	SIGKILL,		"sys: kill",
    58  	SIGBUS,		"sys: bus error",
    59  	SIGSEGV,		"sys: segmentation violation",
    60  	SIGALRM,		"alarm",
    61  	SIGTERM,		"kill",
    62  	SIGURG,		"sys: urgent condition on socket",
    63  	SIGSTOP,		"sys: stop",
    64  	SIGTSTP,		"sys: tstp",
    65  	SIGCONT,		"sys: cont",
    66  	SIGCHLD,		"sys: child",
    67  	SIGTTIN,		"sys: ttin",
    68  	SIGTTOU,		"sys: ttou",
    69  #ifdef SIGIO	/* not on Mac OS X Tiger */
    70  	SIGIO,		"sys: i/o possible on fd",
    71  #endif
    72  	SIGXCPU,		"sys: cpu time limit exceeded",
    73  	SIGXFSZ,		"sys: file size limit exceeded",
    74  	SIGVTALRM,	"sys: virtual time alarm",
    75  	SIGPROF,		"sys: profiling timer alarm",
    76  #ifdef SIGWINCH	/* not on Mac OS X Tiger */
    77  	SIGWINCH,	"sys: window size change",
    78  #endif
    79  #ifdef SIGINFO
    80  	SIGINFO,		"sys: status request",
    81  #endif
    82  	SIGUSR1,		"sys: usr1",
    83  	SIGUSR2,		"sys: usr2",
    84  	SIGPIPE,		"sys: write on closed pipe",
    85  };
    86  
    87  char*
    88  _p9sigstr(int sig, char *tmp)
    89  {
    90  	int i;
    91  
    92  	for(i=0; i<nelem(tab); i++)
    93  		if(tab[i].sig == sig)
    94  			return tab[i].str;
    95  	if(tmp == nil)
    96  		return nil;
    97  	sprint(tmp, "sys: signal %d", sig);
    98  	return tmp;
    99  }
   100  
   101  int
   102  _p9strsig(char *s)
   103  {
   104  	int i;
   105  
   106  	for(i=0; i<nelem(tab); i++)
   107  		if(strcmp(s, tab[i].str) == 0)
   108  			return tab[i].sig;
   109  	return 0;
   110  }
   111  
   112  static Waitmsg*
   113  _wait(int pid4, int opt)
   114  {
   115  	int pid, status, cd;
   116  	struct rusage ru;
   117  	char tmp[64];
   118  	ulong u, s;
   119  	Waitmsg *w;
   120  
   121  	w = malloc(sizeof *w + 200);
   122  	if(w == nil)
   123  		return nil;
   124  	memset(w, 0, sizeof *w);
   125  	w->msg = (char*)&w[1];
   126  
   127  	for(;;){
   128  		/* On Linux, pid==-1 means anyone; on SunOS, it's pid==0. */
   129  		if(pid4 == -1)
   130  			pid = wait3(&status, opt, &ru);
   131  		else
   132  			pid = wait4(pid4, &status, opt, &ru);
   133  		if(pid <= 0) {
   134  			free(w);
   135  			return nil;
   136  		}
   137  		u = (ulong)(ru.ru_utime.tv_sec*1000+((ru.ru_utime.tv_usec+500)/1000));
   138  		s = (ulong)(ru.ru_stime.tv_sec*1000+((ru.ru_stime.tv_usec+500)/1000));
   139  		w->pid = pid;
   140  		w->time[0] = u;
   141  		w->time[1] = s;
   142  		w->time[2] = u+s;
   143  		if(WIFEXITED(status)){
   144  			if(status)
   145  				sprint(w->msg, "%d", status);
   146  			return w;
   147  		}
   148  		if(WIFSIGNALED(status)){
   149  			cd = WCOREDUMP(status);
   150  			sprint(w->msg, "signal: %s", _p9sigstr(WTERMSIG(status), tmp));
   151  			if(cd)
   152  				strcat(w->msg, " (core dumped)");
   153  			return w;
   154  		}
   155  	}
   156  }
   157  
   158  Waitmsg*
   159  p9wait(void)
   160  {
   161  	return _wait(-1, 0);
   162  }
   163  
   164  Waitmsg*
   165  p9waitfor(int pid)
   166  {
   167  	return _wait(pid, 0);
   168  }
   169  
   170  Waitmsg*
   171  p9waitnohang(void)
   172  {
   173  	return _wait(-1, WNOHANG);
   174  }
   175  
   176  int
   177  p9waitpid(void)
   178  {
   179  	int status;
   180  	return wait(&status);
   181  }