granicus.if.org Git - strace/blob - wait.c

   1 #include "defs.h"
   2
   3 #include <sys/wait.h>
   4
   5 #include "xlat/wait4_options.h"
   6
   7 #if !defined WCOREFLAG && defined WCOREFLG
   8 # define WCOREFLAG WCOREFLG
   9 #endif
  10 #ifndef WCOREFLAG
  11 # define WCOREFLAG 0x80
  12 #endif
  13 #ifndef WCOREDUMP
  14 # define WCOREDUMP(status)  ((status) & 0200)
  15 #endif
  16 #ifndef W_STOPCODE
  17 # define W_STOPCODE(sig)  ((sig) << 8 | 0x7f)
  18 #endif
  19 #ifndef W_EXITCODE
  20 # define W_EXITCODE(ret, sig)  ((ret) << 8 | (sig))
  21 #endif
  22 #ifndef W_CONTINUED
  23 # define W_CONTINUED 0xffff
  24 #endif
  25
  26 #include "ptrace.h"
  27 #include "xlat/ptrace_events.h"
  28
  29 static int
  30 printstatus(int status)
  31 {
  32         int exited = 0;
  33
  34         /*
  35          * Here is a tricky presentation problem.  This solution
  36          * is still not entirely satisfactory but since there
  37          * are no wait status constructors it will have to do.
  38          */
  39         if (WIFSTOPPED(status)) {
  40                 int sig = WSTOPSIG(status);
  41                 tprintf("[{WIFSTOPPED(s) && WSTOPSIG(s) == %s%s}",
  42                         signame(sig & 0x7f),
  43                         sig & 0x80 ? " | 0x80" : "");
  44                 status &= ~W_STOPCODE(sig);
  45         }
  46         else if (WIFSIGNALED(status)) {
  47                 tprintf("[{WIFSIGNALED(s) && WTERMSIG(s) == %s%s}",
  48                         signame(WTERMSIG(status)),
  49                         WCOREDUMP(status) ? " && WCOREDUMP(s)" : "");
  50                 status &= ~(W_EXITCODE(0, WTERMSIG(status)) | WCOREFLAG);
  51         }
  52         else if (WIFEXITED(status)) {
  53                 tprintf("[{WIFEXITED(s) && WEXITSTATUS(s) == %d}",
  54                         WEXITSTATUS(status));
  55                 exited = 1;
  56                 status &= ~W_EXITCODE(WEXITSTATUS(status), 0);
  57         }
  58 #ifdef WIFCONTINUED
  59         else if (WIFCONTINUED(status)) {
  60                 tprints("[{WIFCONTINUED(s)}");
  61                 status &= ~W_CONTINUED;
  62         }
  63 #endif
  64         else {
  65                 tprintf("[%#x]", status);
  66                 return 0;
  67         }
  68
  69         if (status) {
  70                 unsigned int event = (unsigned int) status >> 16;
  71                 if (event) {
  72                         tprints(" | ");
  73                         printxval(ptrace_events, event, "PTRACE_EVENT_???");
  74                         tprints(" << 16");
  75                         status &= 0xffff;
  76                 }
  77                 if (status)
  78                         tprintf(" | %#x", status);
  79         }
  80         tprints("]");
  81
  82         return exited;
  83 }
  84
  85 static int
  86 printwaitn(struct tcb *tcp, int n, int bitness)
  87 {
  88         int status;
  89
  90         if (entering(tcp)) {
  91                 /* On Linux, kernel-side pid_t is typedef'ed to int
  92                  * on all arches. Also, glibc-2.8 truncates wait3 and wait4
  93                  * pid argument to int on 64bit arches, producing,
  94                  * for example, wait4(4294967295, ...) instead of -1
  95                  * in strace. We have to use int here, not long.
  96                  */
  97                 int pid = tcp->u_arg[0];
  98                 tprintf("%d, ", pid);
  99         } else {
 100                 /* status */
 101                 if (tcp->u_rval == 0)
 102                         printaddr(tcp->u_arg[1]);
 103                 else if (!umove_or_printaddr(tcp, tcp->u_arg[1], &status))
 104                         printstatus(status);
 105                 /* options */
 106                 tprints(", ");
 107                 printflags(wait4_options, tcp->u_arg[2], "W???");
 108                 if (n == 4) {
 109                         tprints(", ");
 110                         /* usage */
 111                         if (tcp->u_rval > 0) {
 112 #ifdef ALPHA
 113                                 if (bitness)
 114                                         printrusage32(tcp, tcp->u_arg[3]);
 115                                 else
 116 #endif
 117                                         printrusage(tcp, tcp->u_arg[3]);
 118                         }
 119                         else
 120                                 printaddr(tcp->u_arg[3]);
 121                 }
 122         }
 123         return 0;
 124 }
 125
 126 SYS_FUNC(waitpid)
 127 {
 128         return printwaitn(tcp, 3, 0);
 129 }
 130
 131 SYS_FUNC(wait4)
 132 {
 133         return printwaitn(tcp, 4, 0);
 134 }
 135
 136 #ifdef ALPHA
 137 SYS_FUNC(osf_wait4)
 138 {
 139         return printwaitn(tcp, 4, 1);
 140 }
 141 #endif
 142
 143 #include "xlat/waitid_types.h"
 144
 145 SYS_FUNC(waitid)
 146 {
 147         if (entering(tcp)) {
 148                 printxval(waitid_types, tcp->u_arg[0], "P_???");
 149                 tprintf(", %ld, ", tcp->u_arg[1]);
 150         } else {
 151                 /* siginfo */
 152                 printsiginfo_at(tcp, tcp->u_arg[2]);
 153                 /* options */
 154                 tprints(", ");
 155                 printflags(wait4_options, tcp->u_arg[3], "W???");
 156                 if (tcp->s_ent->nargs > 4) {
 157                         /* usage */
 158                         tprints(", ");
 159                         printrusage(tcp, tcp->u_arg[4]);
 160                 }
 161         }
 162         return 0;
 163 }