xbps/lib/external/fexec.c
Juan RP a77727887d Improvements for xbps_fetch_file and xbps_repository_sync_index.
xbps_fetch_file:
	- A temp file is created with .part extension to improve resuming.
	- Files are downloaded in cwd.
	- Switch to futimens(2) and fsync(2).

xbps_repository_sync_index:
	- Do not create local repodir in metadir if it already exists.
	- Simplify the code thanks to new xbps_fetch_file().
2012-11-11 11:29:49 +01:00

131 lines
3.2 KiB
C

/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Matthias Scheler.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#define _BSD_SOURCE /* for vfork and chroot */
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "xbps_api_impl.h"
static int
pfcexec(struct xbps_handle *xhp, const char *file, const char **argv)
{
pid_t child;
int status;
child = vfork();
switch (child) {
case 0:
/*
* If rootdir != / and uid==0 and bin/sh exists,
* change root directory and exec command.
*
* It's assumed that cwd is the target rootdir.
*/
if (strcmp(xhp->rootdir, "/")) {
if (getuid() == 0 && access("bin/sh", X_OK) == 0) {
if (chroot(xhp->rootdir) == -1)
_exit(128);
if (chdir("/") == -1)
_exit(129);
}
}
(void)execv(file, __UNCONST(argv));
_exit(127);
/* NOTREACHED */
case -1:
return -1;
}
while (waitpid(child, &status, 0) < 0) {
if (errno != EINTR)
return -1;
}
if (!WIFEXITED(status))
return -1;
return WEXITSTATUS(status);
}
static int
vfcexec(struct xbps_handle *xhp, const char *arg, va_list ap)
{
const char **argv;
size_t argv_size, argc;
int retval;
argv_size = 16;
if ((argv = malloc(argv_size * sizeof(*argv))) == NULL) {
errno = ENOMEM;
return -1;
}
argv[0] = arg;
argc = 1;
do {
if (argc == argv_size) {
argv_size *= 2;
argv = realloc(argv, argv_size * sizeof(*argv));
if (argv == NULL) {
errno = ENOMEM;
return -1;
}
}
arg = va_arg(ap, const char *);
argv[argc++] = arg;
} while (arg != NULL);
retval = pfcexec(xhp, argv[0], argv);
free(argv);
return retval;
}
int HIDDEN
xbps_file_exec(struct xbps_handle *xhp, const char *arg, ...)
{
va_list ap;
int result;
va_start(ap, arg);
result = vfcexec(xhp, arg, ap);
va_end(ap);
return result;
}