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      1 /*
      2  * utils.c
      3  *
      4  *		This program is free software; you can redistribute it and/or
      5  *		modify it under the terms of the GNU General Public License
      6  *		as published by the Free Software Foundation; either version
      7  *		2 of the License, or (at your option) any later version.
      8  *
      9  * Authors:	Alexey Kuznetsov, <kuznet (at) ms2.inr.ac.ru>
     10  *
     11  */
     12 
     13 #include <stdio.h>
     14 #include <stdlib.h>
     15 #include <unistd.h>
     16 #include <syslog.h>
     17 #include <fcntl.h>
     18 #include <sys/socket.h>
     19 #include <netinet/in.h>
     20 #include <string.h>
     21 #include <netdb.h>
     22 #include <arpa/inet.h>
     23 #include <resolv.h>
     24 #include <asm/types.h>
     25 #include <linux/pkt_sched.h>
     26 #include <time.h>
     27 #include <sys/time.h>
     28 #include <errno.h>
     29 
     30 
     31 #include "utils.h"
     32 
     33 int get_integer(int *val, const char *arg, int base)
     34 {
     35 	long res;
     36 	char *ptr;
     37 
     38 	if (!arg || !*arg)
     39 		return -1;
     40 	res = strtol(arg, &ptr, base);
     41 	if (!ptr || ptr == arg || *ptr || res > INT_MAX || res < INT_MIN)
     42 		return -1;
     43 	*val = res;
     44 	return 0;
     45 }
     46 
     47 int mask2bits(__u32 netmask)
     48 {
     49 	unsigned bits = 0;
     50 	__u32 mask = ntohl(netmask);
     51 	__u32 host = ~mask;
     52 
     53 	/* a valid netmask must be 2^n - 1 */
     54 	if ((host & (host + 1)) != 0)
     55 		return -1;
     56 
     57 	for (; mask; mask <<= 1)
     58 		++bits;
     59 	return bits;
     60 }
     61 
     62 static int get_netmask(unsigned *val, const char *arg, int base)
     63 {
     64 	inet_prefix addr;
     65 
     66 	if (!get_unsigned(val, arg, base))
     67 		return 0;
     68 
     69 	/* try coverting dotted quad to CIDR */
     70 	if (!get_addr_1(&addr, arg, AF_INET) && addr.family == AF_INET) {
     71 		int b = mask2bits(addr.data[0]);
     72 
     73 		if (b >= 0) {
     74 			*val = b;
     75 			return 0;
     76 		}
     77 	}
     78 
     79 	return -1;
     80 }
     81 
     82 int get_unsigned(unsigned *val, const char *arg, int base)
     83 {
     84 	unsigned long res;
     85 	char *ptr;
     86 
     87 	if (!arg || !*arg)
     88 		return -1;
     89 	res = strtoul(arg, &ptr, base);
     90 	if (!ptr || ptr == arg || *ptr || res > UINT_MAX)
     91 		return -1;
     92 	*val = res;
     93 	return 0;
     94 }
     95 
     96 /*
     97  * get_time_rtt is "translated" from a similar routine "get_time" in
     98  * tc_util.c.  We don't use the exact same routine because tc passes
     99  * microseconds to the kernel and the callers of get_time_rtt want to
    100  * pass milliseconds (standard unit for rtt values since 2.6.27), and
    101  * have a different assumption for the units of a "raw" number.
    102  */
    103 int get_time_rtt(unsigned *val, const char *arg, int *raw)
    104 {
    105 	double t;
    106 	unsigned long res;
    107 	char *p;
    108 
    109 	if (strchr(arg,'.') != NULL) {
    110 		t = strtod(arg,&p);
    111 		if (t < 0.0)
    112 			return -1;
    113 	}
    114 	else {
    115 		res = strtoul(arg, &p, 0);
    116 		if (res > UINT_MAX)
    117 			return -1;
    118 		t = (double)res;
    119 	}
    120 	if (p == arg)
    121 		return -1;
    122 	*raw = 1;
    123 
    124 	if (*p) {
    125 		*raw = 0;
    126                 if (strcasecmp(p, "s") == 0 || strcasecmp(p, "sec")==0 ||
    127                     strcasecmp(p, "secs")==0)
    128                         t *= 1000;
    129                 else if (strcasecmp(p, "ms") == 0 || strcasecmp(p, "msec")==0 ||
    130                          strcasecmp(p, "msecs") == 0)
    131 			t *= 1.0; /* allow suffix, do nothing */
    132                 else
    133                         return -1;
    134         }
    135 
    136 	/* emulate ceil() without having to bring-in -lm and always be >= 1 */
    137 
    138 	*val = t;
    139 	if (*val < t)
    140 		*val += 1;
    141 
    142         return 0;
    143 
    144 }
    145 
    146 int get_u64(__u64 *val, const char *arg, int base)
    147 {
    148 	unsigned long long res;
    149 	char *ptr;
    150 
    151 	if (!arg || !*arg)
    152 		return -1;
    153 	res = strtoull(arg, &ptr, base);
    154 	if (!ptr || ptr == arg || *ptr || res == 0xFFFFFFFFULL)
    155  		return -1;
    156  	*val = res;
    157  	return 0;
    158 }
    159 
    160 int get_u32(__u32 *val, const char *arg, int base)
    161 {
    162 	unsigned long res;
    163 	char *ptr;
    164 
    165 	if (!arg || !*arg)
    166 		return -1;
    167 	res = strtoul(arg, &ptr, base);
    168 	if (!ptr || ptr == arg || *ptr || res > 0xFFFFFFFFUL)
    169 		return -1;
    170 	*val = res;
    171 	return 0;
    172 }
    173 
    174 int get_u16(__u16 *val, const char *arg, int base)
    175 {
    176 	unsigned long res;
    177 	char *ptr;
    178 
    179 	if (!arg || !*arg)
    180 		return -1;
    181 	res = strtoul(arg, &ptr, base);
    182 	if (!ptr || ptr == arg || *ptr || res > 0xFFFF)
    183 		return -1;
    184 	*val = res;
    185 	return 0;
    186 }
    187 
    188 int get_u8(__u8 *val, const char *arg, int base)
    189 {
    190 	unsigned long res;
    191 	char *ptr;
    192 
    193 	if (!arg || !*arg)
    194 		return -1;
    195 	res = strtoul(arg, &ptr, base);
    196 	if (!ptr || ptr == arg || *ptr || res > 0xFF)
    197 		return -1;
    198 	*val = res;
    199 	return 0;
    200 }
    201 
    202 int get_s32(__s32 *val, const char *arg, int base)
    203 {
    204 	long res;
    205 	char *ptr;
    206 
    207 	errno = 0;
    208 
    209 	if (!arg || !*arg)
    210 		return -1;
    211 	res = strtol(arg, &ptr, base);
    212 	if (ptr == arg || *ptr ||
    213 	    ((res ==  LONG_MIN || res == LONG_MAX) && errno == ERANGE) ||
    214 	    res > INT32_MAX || res < INT32_MIN)
    215 		return -1;
    216 	*val = res;
    217 	return 0;
    218 }
    219 
    220 int get_s16(__s16 *val, const char *arg, int base)
    221 {
    222 	long res;
    223 	char *ptr;
    224 
    225 	if (!arg || !*arg)
    226 		return -1;
    227 	res = strtol(arg, &ptr, base);
    228 	if (!ptr || ptr == arg || *ptr || res > 0x7FFF || res < -0x8000)
    229 		return -1;
    230 	*val = res;
    231 	return 0;
    232 }
    233 
    234 int get_s8(__s8 *val, const char *arg, int base)
    235 {
    236 	long res;
    237 	char *ptr;
    238 
    239 	if (!arg || !*arg)
    240 		return -1;
    241 	res = strtol(arg, &ptr, base);
    242 	if (!ptr || ptr == arg || *ptr || res > 0x7F || res < -0x80)
    243 		return -1;
    244 	*val = res;
    245 	return 0;
    246 }
    247 
    248 /* This uses a non-standard parsing (ie not inet_aton, or inet_pton)
    249  * because of legacy choice to parse 10.8 as 10.8.0.0 not 10.0.0.8
    250  */
    251 static int get_addr_ipv4(__u8 *ap, const char *cp)
    252 {
    253 	int i;
    254 
    255 	for (i = 0; i < 4; i++) {
    256 		unsigned long n;
    257 		char *endp;
    258 
    259 		n = strtoul(cp, &endp, 0);
    260 		if (n > 255)
    261 			return -1;	/* bogus network value */
    262 
    263 		if (endp == cp) /* no digits */
    264 			return -1;
    265 
    266 		ap[i] = n;
    267 
    268 		if (*endp == '\0')
    269 			break;
    270 
    271 		if (i == 3 || *endp != '.')
    272 			return -1; 	/* extra characters */
    273 		cp = endp + 1;
    274 	}
    275 
    276 	return 1;
    277 }
    278 
    279 int get_addr_1(inet_prefix *addr, const char *name, int family)
    280 {
    281 	memset(addr, 0, sizeof(*addr));
    282 
    283 	if (strcmp(name, "default") == 0 ||
    284 	    strcmp(name, "all") == 0 ||
    285 	    strcmp(name, "any") == 0) {
    286 		if (family == AF_DECnet)
    287 			return -1;
    288 		addr->family = family;
    289 		addr->bytelen = (family == AF_INET6 ? 16 : 4);
    290 		addr->bitlen = -1;
    291 		return 0;
    292 	}
    293 
    294 	if (strchr(name, ':')) {
    295 		addr->family = AF_INET6;
    296 		if (family != AF_UNSPEC && family != AF_INET6)
    297 			return -1;
    298 		if (inet_pton(AF_INET6, name, addr->data) <= 0)
    299 			return -1;
    300 		addr->bytelen = 16;
    301 		addr->bitlen = -1;
    302 		return 0;
    303 	}
    304 
    305 #ifndef ANDROID
    306 	if (family == AF_DECnet) {
    307 		struct dn_naddr dna;
    308 		addr->family = AF_DECnet;
    309 		if (dnet_pton(AF_DECnet, name, &dna) <= 0)
    310 			return -1;
    311 		memcpy(addr->data, dna.a_addr, 2);
    312 		addr->bytelen = 2;
    313 		addr->bitlen = -1;
    314 		return 0;
    315 	}
    316 #endif
    317 
    318 	addr->family = AF_INET;
    319 	if (family != AF_UNSPEC && family != AF_INET)
    320 		return -1;
    321 
    322 	if (get_addr_ipv4((__u8 *)addr->data, name) <= 0)
    323 		return -1;
    324 
    325 	addr->bytelen = 4;
    326 	addr->bitlen = -1;
    327 	return 0;
    328 }
    329 
    330 int get_prefix_1(inet_prefix *dst, char *arg, int family)
    331 {
    332 	int err;
    333 	unsigned plen;
    334 	char *slash;
    335 
    336 	memset(dst, 0, sizeof(*dst));
    337 
    338 	if (strcmp(arg, "default") == 0 ||
    339 	    strcmp(arg, "any") == 0 ||
    340 	    strcmp(arg, "all") == 0) {
    341 		if (family == AF_DECnet)
    342 			return -1;
    343 		dst->family = family;
    344 		dst->bytelen = 0;
    345 		dst->bitlen = 0;
    346 		return 0;
    347 	}
    348 
    349 	slash = strchr(arg, '/');
    350 	if (slash)
    351 		*slash = 0;
    352 
    353 	err = get_addr_1(dst, arg, family);
    354 	if (err == 0) {
    355 		switch(dst->family) {
    356 			case AF_INET6:
    357 				dst->bitlen = 128;
    358 				break;
    359 			case AF_DECnet:
    360 				dst->bitlen = 16;
    361 				break;
    362 			default:
    363 			case AF_INET:
    364 				dst->bitlen = 32;
    365 		}
    366 		if (slash) {
    367 			if (get_netmask(&plen, slash+1, 0)
    368 					|| plen > dst->bitlen) {
    369 				err = -1;
    370 				goto done;
    371 			}
    372 			dst->flags |= PREFIXLEN_SPECIFIED;
    373 			dst->bitlen = plen;
    374 		}
    375 	}
    376 done:
    377 	if (slash)
    378 		*slash = '/';
    379 	return err;
    380 }
    381 
    382 int get_addr(inet_prefix *dst, const char *arg, int family)
    383 {
    384 	if (family == AF_PACKET) {
    385 		fprintf(stderr, "Error: \"%s\" may be inet address, but it is not allowed in this context.\n", arg);
    386 		exit(1);
    387 	}
    388 	if (get_addr_1(dst, arg, family)) {
    389 		fprintf(stderr, "Error: an inet address is expected rather than \"%s\".\n", arg);
    390 		exit(1);
    391 	}
    392 	return 0;
    393 }
    394 
    395 int get_prefix(inet_prefix *dst, char *arg, int family)
    396 {
    397 	if (family == AF_PACKET) {
    398 		fprintf(stderr, "Error: \"%s\" may be inet prefix, but it is not allowed in this context.\n", arg);
    399 		exit(1);
    400 	}
    401 	if (get_prefix_1(dst, arg, family)) {
    402 		fprintf(stderr, "Error: an inet prefix is expected rather than \"%s\".\n", arg);
    403 		exit(1);
    404 	}
    405 	return 0;
    406 }
    407 
    408 __u32 get_addr32(const char *name)
    409 {
    410 	inet_prefix addr;
    411 	if (get_addr_1(&addr, name, AF_INET)) {
    412 		fprintf(stderr, "Error: an IP address is expected rather than \"%s\"\n", name);
    413 		exit(1);
    414 	}
    415 	return addr.data[0];
    416 }
    417 
    418 void incomplete_command(void)
    419 {
    420 	fprintf(stderr, "Command line is not complete. Try option \"help\"\n");
    421 	exit(-1);
    422 }
    423 
    424 void missarg(const char *key)
    425 {
    426 	fprintf(stderr, "Error: argument \"%s\" is required\n", key);
    427 	exit(-1);
    428 }
    429 
    430 void invarg(const char *msg, const char *arg)
    431 {
    432 	fprintf(stderr, "Error: argument \"%s\" is wrong: %s\n", arg, msg);
    433 	exit(-1);
    434 }
    435 
    436 void duparg(const char *key, const char *arg)
    437 {
    438 	fprintf(stderr, "Error: duplicate \"%s\": \"%s\" is the second value.\n", key, arg);
    439 	exit(-1);
    440 }
    441 
    442 void duparg2(const char *key, const char *arg)
    443 {
    444 	fprintf(stderr, "Error: either \"%s\" is duplicate, or \"%s\" is a garbage.\n", key, arg);
    445 	exit(-1);
    446 }
    447 
    448 int matches(const char *cmd, const char *pattern)
    449 {
    450 	int len = strlen(cmd);
    451 	if (len > strlen(pattern))
    452 		return -1;
    453 	return memcmp(pattern, cmd, len);
    454 }
    455 
    456 int inet_addr_match(const inet_prefix *a, const inet_prefix *b, int bits)
    457 {
    458 	const __u32 *a1 = a->data;
    459 	const __u32 *a2 = b->data;
    460 	int words = bits >> 0x05;
    461 
    462 	bits &= 0x1f;
    463 
    464 	if (words)
    465 		if (memcmp(a1, a2, words << 2))
    466 			return -1;
    467 
    468 	if (bits) {
    469 		__u32 w1, w2;
    470 		__u32 mask;
    471 
    472 		w1 = a1[words];
    473 		w2 = a2[words];
    474 
    475 		mask = htonl((0xffffffff) << (0x20 - bits));
    476 
    477 		if ((w1 ^ w2) & mask)
    478 			return 1;
    479 	}
    480 
    481 	return 0;
    482 }
    483 
    484 int __iproute2_hz_internal;
    485 
    486 int __get_hz(void)
    487 {
    488 	char name[1024];
    489 	int hz = 0;
    490 	FILE *fp;
    491 
    492 	if (getenv("HZ"))
    493 		return atoi(getenv("HZ")) ? : HZ;
    494 
    495 	if (getenv("PROC_NET_PSCHED")) {
    496 		snprintf(name, sizeof(name)-1, "%s", getenv("PROC_NET_PSCHED"));
    497 	} else if (getenv("PROC_ROOT")) {
    498 		snprintf(name, sizeof(name)-1, "%s/net/psched", getenv("PROC_ROOT"));
    499 	} else {
    500 		strcpy(name, "/proc/net/psched");
    501 	}
    502 	fp = fopen(name, "r");
    503 
    504 	if (fp) {
    505 		unsigned nom, denom;
    506 		if (fscanf(fp, "%*08x%*08x%08x%08x", &nom, &denom) == 2)
    507 			if (nom == 1000000)
    508 				hz = denom;
    509 		fclose(fp);
    510 	}
    511 	if (hz)
    512 		return hz;
    513 	return HZ;
    514 }
    515 
    516 int __iproute2_user_hz_internal;
    517 
    518 int __get_user_hz(void)
    519 {
    520 	return sysconf(_SC_CLK_TCK);
    521 }
    522 
    523 const char *rt_addr_n2a(int af, int len, const void *addr, char *buf, int buflen)
    524 {
    525 	switch (af) {
    526 	case AF_INET:
    527 	case AF_INET6:
    528 		return inet_ntop(af, addr, buf, buflen);
    529 #ifndef ANDROID
    530 	case AF_IPX:
    531 		return ipx_ntop(af, addr, buf, buflen);
    532 	case AF_DECnet:
    533 	{
    534 		struct dn_naddr dna = { 2, { 0, 0, }};
    535 		memcpy(dna.a_addr, addr, 2);
    536 		return dnet_ntop(af, &dna, buf, buflen);
    537 	}
    538 #endif
    539 	default:
    540 		return "???";
    541 	}
    542 }
    543 
    544 #ifdef RESOLVE_HOSTNAMES
    545 struct namerec
    546 {
    547 	struct namerec *next;
    548 	const char *name;
    549 	inet_prefix addr;
    550 };
    551 
    552 #define NHASH 257
    553 static struct namerec *nht[NHASH];
    554 
    555 static const char *resolve_address(const void *addr, int len, int af)
    556 {
    557 	struct namerec *n;
    558 	struct hostent *h_ent;
    559 	unsigned hash;
    560 	static int notfirst;
    561 
    562 
    563 	if (af == AF_INET6 && ((__u32*)addr)[0] == 0 &&
    564 	    ((__u32*)addr)[1] == 0 && ((__u32*)addr)[2] == htonl(0xffff)) {
    565 		af = AF_INET;
    566 		addr += 12;
    567 		len = 4;
    568 	}
    569 
    570 	hash = *(__u32 *)(addr + len - 4) % NHASH;
    571 
    572 	for (n = nht[hash]; n; n = n->next) {
    573 		if (n->addr.family == af &&
    574 		    n->addr.bytelen == len &&
    575 		    memcmp(n->addr.data, addr, len) == 0)
    576 			return n->name;
    577 	}
    578 	if ((n = malloc(sizeof(*n))) == NULL)
    579 		return NULL;
    580 	n->addr.family = af;
    581 	n->addr.bytelen = len;
    582 	n->name = NULL;
    583 	memcpy(n->addr.data, addr, len);
    584 	n->next = nht[hash];
    585 	nht[hash] = n;
    586 	if (++notfirst == 1)
    587 		sethostent(1);
    588 	fflush(stdout);
    589 
    590 	if ((h_ent = gethostbyaddr(addr, len, af)) != NULL)
    591 		n->name = strdup(h_ent->h_name);
    592 
    593 	/* Even if we fail, "negative" entry is remembered. */
    594 	return n->name;
    595 }
    596 #endif
    597 
    598 
    599 const char *format_host(int af, int len, const void *addr,
    600 			char *buf, int buflen)
    601 {
    602 #ifdef RESOLVE_HOSTNAMES
    603 	if (resolve_hosts) {
    604 		const char *n;
    605 
    606 		if (len <= 0) {
    607 			switch (af) {
    608 			case AF_INET:
    609 				len = 4;
    610 				break;
    611 			case AF_INET6:
    612 				len = 16;
    613 				break;
    614 			case AF_IPX:
    615 				len = 10;
    616 				break;
    617 #ifdef AF_DECnet
    618 			/* I see no reasons why gethostbyname
    619 			   may not work for DECnet */
    620 			case AF_DECnet:
    621 				len = 2;
    622 				break;
    623 #endif
    624 			default: ;
    625 			}
    626 		}
    627 		if (len > 0 &&
    628 		    (n = resolve_address(addr, len, af)) != NULL)
    629 			return n;
    630 	}
    631 #endif
    632 	return rt_addr_n2a(af, len, addr, buf, buflen);
    633 }
    634 
    635 
    636 char *hexstring_n2a(const __u8 *str, int len, char *buf, int blen)
    637 {
    638 	char *ptr = buf;
    639 	int i;
    640 
    641 	for (i=0; i<len; i++) {
    642 		if (blen < 3)
    643 			break;
    644 		sprintf(ptr, "%02x", str[i]);
    645 		ptr += 2;
    646 		blen -= 2;
    647 		if (i != len-1 && blen > 1) {
    648 			*ptr++ = ':';
    649 			blen--;
    650 		}
    651 	}
    652 	return buf;
    653 }
    654 
    655 __u8* hexstring_a2n(const char *str, __u8 *buf, int blen)
    656 {
    657 	int cnt = 0;
    658 
    659 	for (;;) {
    660 		unsigned acc;
    661 		char ch;
    662 
    663 		acc = 0;
    664 
    665 		while ((ch = *str) != ':' && ch != 0) {
    666 			if (ch >= '0' && ch <= '9')
    667 				ch -= '0';
    668 			else if (ch >= 'a' && ch <= 'f')
    669 				ch -= 'a'-10;
    670 			else if (ch >= 'A' && ch <= 'F')
    671 				ch -= 'A'-10;
    672 			else
    673 				return NULL;
    674 			acc = (acc<<4) + ch;
    675 			str++;
    676 		}
    677 
    678 		if (acc > 255)
    679 			return NULL;
    680 		if (cnt < blen) {
    681 			buf[cnt] = acc;
    682 			cnt++;
    683 		}
    684 		if (ch == 0)
    685 			break;
    686 		++str;
    687 	}
    688 	if (cnt < blen)
    689 		memset(buf+cnt, 0, blen-cnt);
    690 	return buf;
    691 }
    692 
    693 int print_timestamp(FILE *fp)
    694 {
    695 	struct timeval tv;
    696 	char *tstr;
    697 
    698 	memset(&tv, 0, sizeof(tv));
    699 	gettimeofday(&tv, NULL);
    700 
    701 	tstr = asctime(localtime(&tv.tv_sec));
    702 	tstr[strlen(tstr)-1] = 0;
    703 	fprintf(fp, "Timestamp: %s %lu usec\n", tstr, tv.tv_usec);
    704 	return 0;
    705 }
    706 
    707 int cmdlineno;
    708 
    709 #ifndef ANDROID
    710 /* Like glibc getline but handle continuation lines and comments */
    711 ssize_t getcmdline(char **linep, size_t *lenp, FILE *in)
    712 {
    713 	ssize_t cc;
    714 	char *cp;
    715 
    716 	if ((cc = getline(linep, lenp, in)) < 0)
    717 		return cc;	/* eof or error */
    718 	++cmdlineno;
    719 
    720 	cp = strchr(*linep, '#');
    721 	if (cp)
    722 		*cp = '\0';
    723 
    724 	while ((cp = strstr(*linep, "\\\n")) != NULL) {
    725 		char *line1 = NULL;
    726 		size_t len1 = 0;
    727 		ssize_t cc1;
    728 
    729 		if ((cc1 = getline(&line1, &len1, in)) < 0) {
    730 			fprintf(stderr, "Missing continuation line\n");
    731 			return cc1;
    732 		}
    733 
    734 		++cmdlineno;
    735 		*cp = 0;
    736 
    737 		cp = strchr(line1, '#');
    738 		if (cp)
    739 			*cp = '\0';
    740 
    741 		*lenp = strlen(*linep) + strlen(line1) + 1;
    742 		*linep = realloc(*linep, *lenp);
    743 		if (!*linep) {
    744 			fprintf(stderr, "Out of memory\n");
    745 			*lenp = 0;
    746 			return -1;
    747 		}
    748 		cc += cc1 - 2;
    749 		strcat(*linep, line1);
    750 		free(line1);
    751 	}
    752 	return cc;
    753 }
    754 #endif
    755 
    756 /* split command line into argument vector */
    757 int makeargs(char *line, char *argv[], int maxargs)
    758 {
    759 	static const char ws[] = " \t\r\n";
    760 	char *cp;
    761 	int argc = 0;
    762 
    763 	for (cp = strtok(line, ws); cp; cp = strtok(NULL, ws)) {
    764 		if (argc >= (maxargs - 1)) {
    765 			fprintf(stderr, "Too many arguments to command\n");
    766 			exit(1);
    767 		}
    768 		argv[argc++] = cp;
    769 	}
    770 	argv[argc] = NULL;
    771 
    772 	return argc;
    773 }
    774