Annotation of prex/usr/lib/posix/exec/execve.c, Revision 1.1
1.1 ! nbrk 1: /*
! 2: * Copyright (c) 2005-2006, Kohsuke Ohtani
! 3: * All rights reserved.
! 4: *
! 5: * Redistribution and use in source and binary forms, with or without
! 6: * modification, are permitted provided that the following conditions
! 7: * are met:
! 8: * 1. Redistributions of source code must retain the above copyright
! 9: * notice, this list of conditions and the following disclaimer.
! 10: * 2. Redistributions in binary form must reproduce the above copyright
! 11: * notice, this list of conditions and the following disclaimer in the
! 12: * documentation and/or other materials provided with the distribution.
! 13: * 3. Neither the name of the author nor the names of any co-contributors
! 14: * may be used to endorse or promote products derived from this software
! 15: * without specific prior written permission.
! 16: *
! 17: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
! 18: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 19: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 20: * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
! 21: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 22: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 23: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 24: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 25: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 26: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 27: * SUCH DAMAGE.
! 28: */
! 29:
! 30: #include <prex/prex.h>
! 31: #include <server/exec.h>
! 32: #include <server/stdmsg.h>
! 33: #include <server/object.h>
! 34:
! 35: #include <limits.h>
! 36: #include <string.h>
! 37: #include <errno.h>
! 38: #include <stdlib.h>
! 39:
! 40: /*
! 41: * Note:
! 42: *
! 43: * The state after exec() are as follow.
! 44: * - Opened file descriptors remain open except FD_CLOEXEC flag is set.
! 45: * - Opened directory streams are closed
! 46: * - Signals set to the default action.
! 47: * - Any asynchronous I/O operations are cancelled.
! 48: */
! 49: int
! 50: execve(char *path, char *argv[], char *envp[])
! 51: {
! 52: object_t exec_obj;
! 53: struct exec_msg msg;
! 54: int err, i, argc, envc;
! 55: size_t bufsz;
! 56: char *dest, *src;
! 57:
! 58: if ((err = object_lookup(OBJNAME_EXEC, &exec_obj)) != 0)
! 59: return ENOSYS;
! 60:
! 61: if (path == NULL)
! 62: return EFAULT;
! 63: /*
! 64: if (strlen(path) >= PATH_MAX)
! 65: return ENAMETOOLONG;
! 66: */
! 67:
! 68: /* Get arg/env buffer size */
! 69: bufsz = 0;
! 70:
! 71: argc = 0;
! 72: if (argv) {
! 73: while (argv[argc]) {
! 74: bufsz += (strlen(argv[argc]) + 1);
! 75: argc++;
! 76: }
! 77: }
! 78: envc = 0;
! 79: if (envp) {
! 80: while (envp[envc]) {
! 81: bufsz += (strlen(envp[envc]) + 1);
! 82: envc++;
! 83: }
! 84: }
! 85: if (bufsz >= ARG_MAX)
! 86: return E2BIG;
! 87:
! 88: dest = msg.buf;
! 89: for (i = 0; i < argc; i++) {
! 90: src = argv[i];
! 91: while ((*dest++ = *src++) != 0);
! 92: }
! 93: for (i = 0; i < envc; i++) {
! 94: src = envp[i];
! 95: while ((*dest++ = *src++) != 0);
! 96: }
! 97:
! 98: /* Request to exec server */
! 99: msg.hdr.code = EX_EXEC;
! 100: msg.argc = argc;
! 101: msg.envc = envc;
! 102: msg.bufsz = bufsz;
! 103: strlcpy(msg.path, path, PATH_MAX);
! 104:
! 105: do {
! 106: err = msg_send(exec_obj, &msg, sizeof(msg));
! 107: } while (err == EINTR);
! 108:
! 109: /*
! 110: * If exec() request is done successfully, control never comes here.
! 111: */
! 112: errno = 0;
! 113: if (err)
! 114: errno = EIO;
! 115: else if (msg.hdr.status)
! 116: errno = msg.hdr.status;
! 117:
! 118: return -1;
! 119: }
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