mdw@git.distorted.org.uk Git - termux-packages/blob - packages/ninja/src-posix_spawn.c.patch

   1 diff --git a/src/posix_spawn.c b/src/posix_spawn.c
   2 new file mode 100644
   3 index 0000000..18ceb06
   4 --- /dev/null
   5 +++ b/src/posix_spawn.c
   6 @@ -0,0 +1,156 @@
   7 +/*
   8 + * dhcpcd - DHCP client daemon
   9 + * Copyright (c) 2006-2012 Roy Marples <roy@marples.name>
  10 + * All rights reserved
  11 +
  12 + * Redistribution and use in source and binary forms, with or without
  13 + * modification, are permitted provided that the following conditions
  14 + * are met:
  15 + * 1. Redistributions of source code must retain the above copyright
  16 + *    notice, this list of conditions and the following disclaimer.
  17 + * 2. Redistributions in binary form must reproduce the above copyright
  18 + *    notice, this list of conditions and the following disclaimer in the
  19 + *    documentation and/or other materials provided with the distribution.
  20 + *
  21 + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  22 + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23 + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24 + * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  25 + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26 + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27 + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29 + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30 + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31 + * SUCH DAMAGE.
  32 + */
  33 +
  34 +/* This implementation of posix_spawn is only suitable for the needs of dhcpcd
  35 + * but it could easily be extended to other applications. */
  36 +
  37 +#include <sys/types.h>
  38 +#include <sys/wait.h>
  39 +
  40 +#include <errno.h>
  41 +#include <signal.h>
  42 +#include <stdlib.h>
  43 +#include <string.h>
  44 +#include <unistd.h>
  45 +
  46 +#include "posix_spawn.h"
  47 +
  48 +#ifndef _NSIG
  49 +#ifdef _SIG_MAXSIG
  50 +#define _NSIG _SIG_MAXSIG + 1
  51 +#else
  52 +/* Guess */
  53 +#define _NSIG SIGPWR + 1
  54 +#endif
  55 +#endif
  56 +
  57 +extern char **environ;
  58 +
  59 +static int
  60 +posix_spawnattr_handle(const posix_spawnattr_t *attrp)
  61 +{
  62 +       struct sigaction sa;
  63 +       int i;
  64 +
  65 +       if (attrp->posix_attr_flags & POSIX_SPAWN_SETSIGMASK)
  66 +               sigprocmask(SIG_SETMASK, &attrp->posix_attr_sigmask, NULL);
  67 +
  68 +       if (attrp->posix_attr_flags & POSIX_SPAWN_SETSIGDEF) {
  69 +               memset(&sa, 0, sizeof(sa));
  70 +               sa.sa_handler = SIG_DFL;
  71 +               for (i = 1; i < _NSIG; i++) {
  72 +                       if (sigismember(&attrp->posix_attr_sigdefault, i)) {
  73 +                               if (sigaction(i, &sa, NULL) == -1)
  74 +                                       return -1;
  75 +                       }
  76 +               }
  77 +       }
  78 +
  79 +       return 0;
  80 +}
  81 +
  82 +inline static int
  83 +is_vfork_safe(short int flags)
  84 +{
  85 +       return !(flags & (POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK));
  86 +}
  87 +
  88 +int
  89 +posix_spawn(pid_t *pid, const char *path,
  90 +       const posix_spawn_file_actions_t *file_actions,
  91 +       const posix_spawnattr_t *attrp,
  92 +       char *const argv[], char *const envp[])
  93 +{
  94 +       short int flags;
  95 +       pid_t p;
  96 +       volatile int error;
  97 +
  98 +       error = 0;
  99 +       flags = attrp ? attrp->posix_attr_flags : 0;
 100 +       if (file_actions == NULL && is_vfork_safe(flags))
 101 +               p = vfork();
 102 +       else
 103 +#ifdef THERE_IS_NO_FORK
 104 +               return ENOSYS;
 105 +#else
 106 +               p = fork();
 107 +#endif
 108 +       switch (p) {
 109 +       case -1:
 110 +               return errno;
 111 +       case 0:
 112 +               if (attrp) {
 113 +                       error = posix_spawnattr_handle(attrp);
 114 +                       if (error)
 115 +                               _exit(127);
 116 +               }
 117 +               execve(path, argv, envp);
 118 +               error = errno;
 119 +               _exit(127);
 120 +       default:
 121 +               if (error != 0)
 122 +                       waitpid(p, NULL, WNOHANG);
 123 +               else if (pid != NULL)
 124 +                       *pid = p;
 125 +               return error;
 126 +       }
 127 +}
 128 +
 129 +int
 130 +posix_spawnattr_init(posix_spawnattr_t *attr)
 131 +{
 132 +
 133 +       memset(attr, 0, sizeof(*attr));
 134 +       attr->posix_attr_flags = 0;
 135 +       sigprocmask(0, NULL, &attr->posix_attr_sigmask);
 136 +       sigemptyset(&attr->posix_attr_sigdefault);
 137 +       return 0;
 138 +}
 139 +
 140 +int
 141 +posix_spawnattr_setflags(posix_spawnattr_t *attr, short flags)
 142 +{
 143 +
 144 +       attr->posix_attr_flags = flags;
 145 +       return 0;
 146 +}
 147 +
 148 +int
 149 +posix_spawnattr_setsigmask(posix_spawnattr_t *attr, const sigset_t *sigmask)
 150 +{
 151 +
 152 +       attr->posix_attr_sigmask = *sigmask;
 153 +       return 0;
 154 +}
 155 +
 156 +int
 157 +posix_spawnattr_setsigdefault(posix_spawnattr_t *attr, const sigset_t *sigmask)
 158 +{
 159 +
 160 +       attr->posix_attr_sigdefault = *sigmask;
 161 +       return 0;
 162 +}