Differential D22012 Diff 97323 contrib/dhcpcd/src/common.c

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contrib/dhcpcd/src/common.c

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				/* SPDX-License-Identifier: BSD-2-Clause */
				/*
				* dhcpcd - DHCP client daemon
				* Copyright (c) 2006-2021 Roy Marples <roy@marples.name>
				* All rights reserved

				* 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 AUTHOR 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 AUTHOR 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.
				*/

				#include <sys/stat.h>
				#include <sys/statvfs.h>

				#include <ctype.h>
				#include <errno.h>
				#include <fcntl.h>
				#include <stdio.h>
				#include <stdlib.h>
				#include <string.h>

				#include "common.h"
				#include "dhcpcd.h"
				#include "if-options.h"

				const char *
				hwaddr_ntoa(const void hwaddr, size_t hwlen, char buf, size_t buflen)
				{
				const unsigned char hp, ep;
				char *p;

				if (buf == NULL \|\| hwlen == 0)
				return NULL;

				if (hwlen * 3 > buflen) {
				errno = ENOBUFS;
				return NULL;
				}

				hp = hwaddr;
				ep = hp + hwlen;
				p = buf;

				while (hp < ep) {
				if (hp != hwaddr)
				*p ++= ':';
				p += snprintf(p, 3, "%.2x", *hp++);
				}
				*p ++= '\0';
				return buf;
				}

				size_t
				hwaddr_aton(uint8_t buffer, const char addr)
				{
				char c[3];
				const char *p = addr;
				uint8_t *bp = buffer;
				size_t len = 0;

				c[2] = '\0';
				while (*p != '\0') {
				/* Skip separators */
				c[0] = *p++;
				switch (c[0]) {
				case '\n': /* long duid split on lines */
				case ':': /* typical mac address */
				case '-': /* uuid */
				continue;
				}
				c[1] = *p++;
				/* Ensure that digits are hex */
				if (isxdigit((unsigned char)c[0]) == 0 \|\|
				isxdigit((unsigned char)c[1]) == 0)
				{
				errno = EINVAL;
				return 0;
				}
				/* We should have at least two entries 00:01 */
				if (len == 0 && *p == '\0') {
				errno = EINVAL;
				return 0;
				}
				if (bp)
				*bp++ = (uint8_t)strtol(c, NULL, 16);
				len++;
				}
				return len;
				}

				ssize_t
				readfile(const char file, void data, size_t len)
				{
				int fd;
				ssize_t bytes;

				fd = open(file, O_RDONLY);
				if (fd == -1)
				return -1;
				bytes = read(fd, data, len);
				close(fd);
				if ((size_t)bytes == len) {
				errno = ENOBUFS;
				return -1;
				}
				return bytes;
				}

				ssize_t
				writefile(const char file, mode_t mode, const void data, size_t len)
				{
				int fd;
				ssize_t bytes;

				fd = open(file, O_WRONLY \| O_CREAT \| O_TRUNC, mode);
				if (fd == -1)
				return -1;
				bytes = write(fd, data, len);
				close(fd);
				return bytes;
				}

				int
				filemtime(const char file, time_t time)
				{
				struct stat st;

				if (stat(file, &st) == -1)
				return -1;
				*time = st.st_mtime;
				return 0;
				}

				/* Handy routine to read very long lines in text files.
				* This means we read the whole line and avoid any nasty buffer overflows.
				* We strip leading space and avoid comment lines, making the code that calls
				* us smaller. */
				char *
				get_line(char ** __restrict buf, ssize_t * __restrict buflen)
				{
				char p, c;
				bool quoted;

				do {
				p = *buf;
				if (*buf == NULL)
				return NULL;
				c = memchr(buf, '\n', (size_t)buflen);
				if (c == NULL) {
				c = memchr(buf, '\0', (size_t)buflen);
				if (c == NULL)
				return NULL;
				buflen = c - buf;
				*buf = NULL;
				} else {
				*c++ = '\0';
				buflen -= c - buf;
				*buf = c;
				}
				for (; p == ' ' \|\| p == '\t'; p++)
				;
				} while (p == '\0' \|\| p == '\n' \|\| p == '#' \|\| p == ';');

				/* Strip embedded comments unless in a quoted string or escaped */
				quoted = false;
				for (c = p; *c != '\0'; c++) {
				if (*c == '\\') {
				c++; /* escaped */
				continue;
				}
				if (*c == '"')
				quoted = !quoted;
				else if (*c == '#' && !quoted) {
				*c = '\0';
				break;
				}
				}
				return p;
				}


				int
				is_root_local(void)
				{
				#ifdef ST_LOCAL
				struct statvfs vfs;

				if (statvfs("/", &vfs) == -1)
				return -1;
				return vfs.f_flag & ST_LOCAL ? 1 : 0;
				#else
				errno = ENOTSUP;
				return -1;
				#endif
				}