2 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
23 * txtproto_print() derived from original code by Hannes Gredler
24 * (hannes@gredler.at):
26 * Redistribution and use in source and binary forms, with or without
27 * modification, are permitted provided that: (1) source code
28 * distributions retain the above copyright notice and this paragraph
29 * in its entirety, and (2) distributions including binary code include
30 * the above copyright notice and this paragraph in its entirety in
31 * the documentation or other materials provided with the distribution.
32 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
33 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
34 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
35 * FOR A PARTICULAR PURPOSE.
42 #include "netdissect-stdinc.h"
55 #include "netdissect.h"
57 #include "ascii_strcasecmp.h"
58 #include "timeval-operations.h"
60 /* invalid string to print '(invalid)' for malformed or corrupted packets */
61 const char istr
[] = " (invalid)";
63 #define TOKBUFSIZE 128
66 enum date_flag
{ WITHOUT_DATE
= 0, WITH_DATE
= 1 };
67 enum time_flag
{ UTC_TIME
= 0, LOCAL_TIME
= 1 };
70 * Print out a character, filtering out the non-printable ones
73 fn_print_char(netdissect_options
*ndo
, u_char c
)
80 c
^= 0x40; /* DEL to ?, others to alpha */
87 * Print a null-terminated string, filtering out non-printable characters.
88 * DON'T USE IT with a pointer on the packet buffer because there is no
89 * truncation check. For this use, see the nd_printX() functions below.
92 fn_print_str(netdissect_options
*ndo
, const u_char
*s
)
95 fn_print_char(ndo
, *s
);
101 * Print out a null-terminated filename (or other ASCII string), part of
103 * If ep is NULL, assume no truncation check is needed.
104 * Return true if truncated.
105 * Stop at ep (if given) or before the null char, whichever is first.
108 nd_print(netdissect_options
*ndo
,
109 const u_char
*s
, const u_char
*ep
)
114 ret
= 1; /* assume truncated */
115 while (ep
== NULL
|| s
< ep
) {
122 fn_print_char(ndo
, c
);
128 * Print out a null-terminated filename (or other ASCII string) from
129 * a fixed-length field in the packet buffer, or from what remains of
132 * n is the length of the fixed-length field, or the number of bytes
133 * remaining in the packet based on its on-the-network length.
135 * If ep is non-null, it should point just past the last captured byte
136 * of the packet, e.g. ndo->ndo_snapend. If ep is NULL, we assume no
137 * truncation check, other than the checks of the field length/remaining
138 * packet data length, is needed.
140 * Return the number of bytes of string processed, including the
141 * terminating null, if not truncated; as the terminating null is
142 * included in the count, and as there must be a terminating null,
143 * this will always be non-zero. Return 0 if truncated.
146 nd_printztn(netdissect_options
*ndo
,
147 const u_char
*s
, u_int n
, const u_char
*ep
)
154 if (n
== 0 || (ep
!= NULL
&& s
>= ep
)) {
156 * Truncated. This includes "no null before we
157 * got to the end of the fixed-length buffer or
158 * the end of the packet".
160 * XXX - BOOTP says "null-terminated", which
161 * means the maximum length of the string, in
162 * bytes, is 1 less than the size of the buffer,
163 * as there must always be a terminating null.
177 fn_print_char(ndo
, c
);
183 * Print out a counted filename (or other ASCII string), part of
185 * If ep is NULL, assume no truncation check is needed.
186 * Return true if truncated.
187 * Stop at ep (if given) or after n bytes, whichever is first.
190 nd_printn(netdissect_options
*ndo
,
191 const u_char
*s
, u_int n
, const u_char
*ep
)
195 while (n
> 0 && (ep
== NULL
|| s
< ep
)) {
199 fn_print_char(ndo
, c
);
201 return (n
== 0) ? 0 : 1;
205 * Print out a null-padded filename (or other ASCII string), part of
207 * If ep is NULL, assume no truncation check is needed.
208 * Return true if truncated.
209 * Stop at ep (if given) or after n bytes or before the null char,
210 * whichever is first.
213 nd_printzp(netdissect_options
*ndo
,
214 const u_char
*s
, u_int n
,
220 ret
= 1; /* assume truncated */
221 while (n
> 0 && (ep
== NULL
|| s
< ep
)) {
229 fn_print_char(ndo
, c
);
231 return (n
== 0) ? 0 : ret
;
235 * Print the timestamp as [YY:MM:DD] HH:MM:SS.FRAC.
236 * if time_flag == LOCAL_TIME print local time else UTC/GMT time
237 * if date_flag == WITH_DATE print YY:MM:DD before HH:MM:SS.FRAC
240 ts_date_hmsfrac_print(netdissect_options
*ndo
, int sec
, int usec
,
241 enum date_flag date_flag
, enum time_flag time_flag
)
247 if (time_flag
== LOCAL_TIME
)
248 tm
= localtime(&Time
);
253 ND_PRINT("[Error converting time]");
256 if (date_flag
== WITH_DATE
)
257 strftime(timestr
, sizeof(timestr
), "%Y-%m-%d %H:%M:%S", tm
);
259 strftime(timestr
, sizeof(timestr
), "%H:%M:%S", tm
);
260 ND_PRINT("%s", timestr
);
262 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
263 switch (ndo
->ndo_tstamp_precision
) {
265 case PCAP_TSTAMP_PRECISION_MICRO
:
266 ND_PRINT(".%06u", usec
);
269 case PCAP_TSTAMP_PRECISION_NANO
:
270 ND_PRINT(".%09u", usec
);
274 ND_PRINT(".{unknown}");
278 ND_PRINT(".%06u", usec
);
283 * Print the timestamp - Unix timeval style, as SECS.FRAC.
286 ts_unix_print(netdissect_options
*ndo
, int sec
, int usec
)
288 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
289 switch (ndo
->ndo_tstamp_precision
) {
291 case PCAP_TSTAMP_PRECISION_MICRO
:
292 ND_PRINT("%u.%06u", (unsigned)sec
, (unsigned)usec
);
295 case PCAP_TSTAMP_PRECISION_NANO
:
296 ND_PRINT("%u.%09u", (unsigned)sec
, (unsigned)usec
);
300 ND_PRINT("%u.{unknown}", (unsigned)sec
);
304 ND_PRINT("%u.%06u", (unsigned)sec
, (unsigned)usec
);
309 * Print the timestamp
312 ts_print(netdissect_options
*ndo
,
313 const struct timeval
*tvp
)
315 static struct timeval tv_ref
;
316 struct timeval tv_result
;
320 switch (ndo
->ndo_tflag
) {
322 case 0: /* Default */
323 ts_date_hmsfrac_print(ndo
, tvp
->tv_sec
, tvp
->tv_usec
,
324 WITHOUT_DATE
, LOCAL_TIME
);
328 case 1: /* No time stamp */
331 case 2: /* Unix timeval style */
332 ts_unix_print(ndo
, tvp
->tv_sec
, tvp
->tv_usec
);
336 case 3: /* Microseconds/nanoseconds since previous packet */
337 case 5: /* Microseconds/nanoseconds since first packet */
338 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
339 switch (ndo
->ndo_tstamp_precision
) {
340 case PCAP_TSTAMP_PRECISION_MICRO
:
343 case PCAP_TSTAMP_PRECISION_NANO
:
353 if (!(netdissect_timevalisset(&tv_ref
)))
354 tv_ref
= *tvp
; /* set timestamp for first packet */
356 negative_offset
= netdissect_timevalcmp(tvp
, &tv_ref
, <);
358 netdissect_timevalsub(&tv_ref
, tvp
, &tv_result
, nano_prec
);
360 netdissect_timevalsub(tvp
, &tv_ref
, &tv_result
, nano_prec
);
362 ND_PRINT((negative_offset
? "-" : " "));
363 ts_date_hmsfrac_print(ndo
, tv_result
.tv_sec
, tv_result
.tv_usec
,
364 WITHOUT_DATE
, UTC_TIME
);
367 if (ndo
->ndo_tflag
== 3)
368 tv_ref
= *tvp
; /* set timestamp for previous packet */
371 case 4: /* Date + Default */
372 ts_date_hmsfrac_print(ndo
, tvp
->tv_sec
, tvp
->tv_usec
,
373 WITH_DATE
, LOCAL_TIME
);
380 * Print an unsigned relative number of seconds (e.g. hold time, prune timer)
381 * in the form 5m1s. This does no truncation, so 32230861 seconds
382 * is represented as 1y1w1d1h1m1s.
385 unsigned_relts_print(netdissect_options
*ndo
,
388 static const char *lengths
[] = {"y", "w", "d", "h", "m", "s"};
389 static const u_int seconds
[] = {31536000, 604800, 86400, 3600, 60, 1};
390 const char **l
= lengths
;
391 const u_int
*s
= seconds
;
399 ND_PRINT("%u%s", secs
/ *s
, *l
);
400 secs
-= (secs
/ *s
) * *s
;
408 * Print a signed relative number of seconds (e.g. hold time, prune timer)
409 * in the form 5m1s. This does no truncation, so 32230861 seconds
410 * is represented as 1y1w1d1h1m1s.
413 signed_relts_print(netdissect_options
*ndo
,
418 if (secs
== INT32_MIN
) {
420 * -2^31; you can't fit its absolute value into
421 * a 32-bit signed integer.
423 * Just directly pass said absolute value to
424 * unsigned_relts_print() directly.
426 * (XXX - does ISO C guarantee that -(-2^n),
427 * when calculated and cast to an n-bit unsigned
428 * integer type, will have the value 2^n?)
430 unsigned_relts_print(ndo
, 2147483648U);
433 * We now know -secs will fit into an int32_t;
434 * negate it and pass that to unsigned_relts_print().
436 unsigned_relts_print(ndo
, -secs
);
440 unsigned_relts_print(ndo
, secs
);
443 /* Print the truncated string */
444 void nd_print_trunc(netdissect_options
*ndo
)
446 ND_PRINT(" [|%s]", ndo
->ndo_protocol
);
450 * this is a generic routine for printing unknown data;
451 * we pass on the linefeed plus indentation string to
452 * get a proper output - returns 0 on error
456 print_unknown_data(netdissect_options
*ndo
, const u_char
*cp
,const char *ident
,int len
)
459 ND_PRINT("%sDissector error: print_unknown_data called with negative length",
463 if (ndo
->ndo_snapend
- cp
< len
)
464 len
= ndo
->ndo_snapend
- cp
;
466 ND_PRINT("%sDissector error: print_unknown_data called with pointer past end of packet",
470 hex_print(ndo
, ident
,cp
,len
);
471 return(1); /* everything is ok */
475 * Convert a token value to a string; use "fmt" if not found.
478 tok2strbuf(const struct tok
*lp
, const char *fmt
,
479 u_int v
, char *buf
, size_t bufsize
)
482 while (lp
->s
!= NULL
) {
491 (void)nd_snprintf(buf
, bufsize
, fmt
, v
);
492 return (const char *)buf
;
496 * Convert a token value to a string; use "fmt" if not found.
497 * Uses tok2strbuf() on one of four local static buffers of size TOKBUFSIZE
498 * in round-robin fashion.
501 tok2str(const struct tok
*lp
, const char *fmt
,
504 static char buf
[4][TOKBUFSIZE
];
510 return tok2strbuf(lp
, fmt
, v
, ret
, sizeof(buf
[0]));
514 * Convert a bit token value to a string; use "fmt" if not found.
515 * this is useful for parsing bitfields, the output strings are separated
516 * if the s field is positive.
519 bittok2str_internal(const struct tok
*lp
, const char *fmt
,
520 u_int v
, const char *sep
)
522 static char buf
[1024+1]; /* our string buffer */
524 size_t space_left
= sizeof(buf
), string_size
;
525 u_int rotbit
; /* this is the bit we rotate through all bitpositions */
527 const char * sepstr
= "";
529 while (lp
!= NULL
&& lp
->s
!= NULL
) {
530 tokval
=lp
->v
; /* load our first value */
532 while (rotbit
!= 0) {
534 * lets AND the rotating bit with our token value
535 * and see if we have got a match
537 if (tokval
== (v
&rotbit
)) {
538 /* ok we have found something */
540 return (buf
); /* only enough room left for NUL, if that */
541 string_size
= strlcpy(bufp
, sepstr
, space_left
);
542 if (string_size
>= space_left
)
543 return (buf
); /* we ran out of room */
545 space_left
-= string_size
;
547 return (buf
); /* only enough room left for NUL, if that */
548 string_size
= strlcpy(bufp
, lp
->s
, space_left
);
549 if (string_size
>= space_left
)
550 return (buf
); /* we ran out of room */
552 space_left
-= string_size
;
556 rotbit
=rotbit
<<1; /* no match - lets shift and try again */
562 /* bummer - lets print the "unknown" message as advised in the fmt string if we got one */
563 (void)nd_snprintf(buf
, sizeof(buf
), fmt
== NULL
? "#%08x" : fmt
, v
);
568 * Convert a bit token value to a string; use "fmt" if not found.
569 * this is useful for parsing bitfields, the output strings are not separated.
572 bittok2str_nosep(const struct tok
*lp
, const char *fmt
,
575 return (bittok2str_internal(lp
, fmt
, v
, ""));
579 * Convert a bit token value to a string; use "fmt" if not found.
580 * this is useful for parsing bitfields, the output strings are comma separated.
583 bittok2str(const struct tok
*lp
, const char *fmt
,
586 return (bittok2str_internal(lp
, fmt
, v
, ", "));
590 * Convert a value to a string using an array; the macro
591 * tok2strary() in <netdissect.h> is the public interface to
592 * this function and ensures that the second argument is
593 * correct for bounds-checking.
596 tok2strary_internal(const char **lp
, int n
, const char *fmt
,
599 static char buf
[TOKBUFSIZE
];
601 if (v
>= 0 && v
< n
&& lp
[v
] != NULL
)
605 (void)nd_snprintf(buf
, sizeof(buf
), fmt
, v
);
610 * Convert a 32-bit netmask to prefixlen if possible
611 * the function returns the prefix-len; if plen == -1
612 * then conversion was not possible;
616 mask2plen(uint32_t mask
)
618 uint32_t bitmasks
[33] = {
620 0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
621 0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
622 0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
623 0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
624 0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
625 0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
626 0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
627 0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff
631 /* let's see if we can transform the mask into a prefixlen */
632 while (prefix_len
>= 0) {
633 if (bitmasks
[prefix_len
] == mask
)
641 mask62plen(const u_char
*mask
)
643 u_char bitmasks
[9] = {
645 0x80, 0xc0, 0xe0, 0xf0,
646 0xf8, 0xfc, 0xfe, 0xff
651 for (byte
= 0; byte
< 16; byte
++) {
654 for (bits
= 0; bits
< (sizeof (bitmasks
) / sizeof (bitmasks
[0])); bits
++) {
655 if (mask
[byte
] == bitmasks
[bits
]) {
661 if (mask
[byte
] != 0xff)
668 * Routine to print out information for text-based protocols such as FTP,
669 * HTTP, SMTP, RTSP, SIP, ....
671 #define MAX_TOKEN 128
674 * Fetch a token from a packet, starting at the specified index,
675 * and return the length of the token.
677 * Returns 0 on error; yes, this is indistinguishable from an empty
678 * token, but an "empty token" isn't a valid token - it just means
679 * either a space character at the beginning of the line (this
680 * includes a blank line) or no more tokens remaining on the line.
683 fetch_token(netdissect_options
*ndo
, const u_char
*pptr
, u_int idx
, u_int len
,
684 u_char
*tbuf
, size_t tbuflen
)
688 for (; idx
< len
; idx
++) {
689 if (!ND_TTEST_1(pptr
+ idx
)) {
690 /* ran past end of captured data */
693 if (!isascii(EXTRACT_U_1(pptr
+ idx
))) {
694 /* not an ASCII character */
697 if (isspace(EXTRACT_U_1(pptr
+ idx
))) {
701 if (!isprint(EXTRACT_U_1(pptr
+ idx
))) {
702 /* not part of a command token or response code */
705 if (toklen
+ 2 > tbuflen
) {
706 /* no room for this character and terminating '\0' */
709 tbuf
[toklen
] = EXTRACT_U_1(pptr
+ idx
);
719 * Skip past any white space after the token, until we see
720 * an end-of-line (CR or LF).
722 for (; idx
< len
; idx
++) {
723 if (!ND_TTEST_1(pptr
+ idx
)) {
724 /* ran past end of captured data */
727 if (EXTRACT_U_1(pptr
+ idx
) == '\r' || EXTRACT_U_1(pptr
+ idx
) == '\n') {
731 if (!isascii(EXTRACT_U_1(pptr
+ idx
)) || !isprint(EXTRACT_U_1(pptr
+ idx
))) {
732 /* not a printable ASCII character */
735 if (!isspace(EXTRACT_U_1(pptr
+ idx
))) {
736 /* beginning of next token */
744 * Scan a buffer looking for a line ending - LF or CR-LF.
745 * Return the index of the character after the line ending or 0 if
746 * we encounter a non-ASCII or non-printable character or don't find
750 print_txt_line(netdissect_options
*ndo
, const char *protoname
,
751 const char *prefix
, const u_char
*pptr
, u_int idx
, u_int len
)
758 ND_TCHECK_1(pptr
+ idx
);
759 if (EXTRACT_U_1(pptr
+ idx
) == '\n') {
761 * LF without CR; end of line.
762 * Skip the LF and print the line, with the
763 * exception of the LF.
765 linelen
= idx
- startidx
;
768 } else if (EXTRACT_U_1(pptr
+ idx
) == '\r') {
770 if ((idx
+1) >= len
) {
771 /* not in this packet */
774 ND_TCHECK_1(pptr
+ idx
+ 1);
775 if (EXTRACT_U_1(pptr
+ idx
+ 1) == '\n') {
777 * CR-LF; end of line.
778 * Skip the CR-LF and print the line, with
779 * the exception of the CR-LF.
781 linelen
= idx
- startidx
;
787 * CR followed by something else; treat this
788 * as if it were binary data, and don't print
792 } else if (!isascii(EXTRACT_U_1(pptr
+ idx
)) ||
793 (!isprint(EXTRACT_U_1(pptr
+ idx
)) &&
794 EXTRACT_U_1(pptr
+ idx
) != '\t')) {
796 * Not a printable ASCII character and not a tab;
797 * treat this as if it were binary data, and
806 * All printable ASCII, but no line ending after that point
807 * in the buffer; treat this as if it were truncated.
810 linelen
= idx
- startidx
;
811 ND_PRINT("%s%.*s[!%s]", prefix
, (int)linelen
, pptr
+ startidx
,
816 ND_PRINT("%s%.*s", prefix
, (int)linelen
, pptr
+ startidx
);
821 txtproto_print(netdissect_options
*ndo
, const u_char
*pptr
, u_int len
,
822 const char *protoname
, const char **cmds
, u_int flags
)
825 u_char token
[MAX_TOKEN
+1];
832 * This protocol has more than just request and
833 * response lines; see whether this looks like a
834 * request or response and, if so, print it and,
835 * in verbose mode, print everything after it.
837 * This is for HTTP-like protocols, where we
838 * want to print requests and responses, but
839 * don't want to print continuations of request
840 * or response bodies in packets that don't
841 * contain the request or response line.
843 idx
= fetch_token(ndo
, pptr
, 0, len
, token
, sizeof(token
));
845 /* Is this a valid request name? */
846 while ((cmd
= *cmds
++) != NULL
) {
847 if (ascii_strcasecmp((const char *)token
, cmd
) == 0) {
855 * No - is this a valid response code (3 digits)?
857 * Is this token the response code, or is the next
858 * token the response code?
860 if (flags
& RESP_CODE_SECOND_TOKEN
) {
862 * Next token - get it.
864 idx
= fetch_token(ndo
, pptr
, idx
, len
, token
,
868 if (isdigit(token
[0]) && isdigit(token
[1]) &&
869 isdigit(token
[2]) && token
[3] == '\0') {
879 * 1) This protocol has only request and response lines
880 * (e.g., FTP, where all the data goes over a different
881 * connection); assume the payload is a request or
886 * 2) This protocol is just text, so that we should
887 * always, at minimum, print the first line and,
888 * in verbose mode, print all lines.
893 /* Capitalize the protocol name */
894 for (pnp
= protoname
; *pnp
!= '\0'; pnp
++)
895 ND_PRINT("%c", toupper((u_char
)*pnp
));
899 * In non-verbose mode, just print the protocol, followed
902 * In verbose mode, print lines as text until we run out
903 * of characters or see something that's not a
904 * printable-ASCII line.
906 if (ndo
->ndo_vflag
) {
908 * We're going to print all the text lines in the
909 * request or response; just print the length
910 * on the first line of the output.
912 ND_PRINT(", length: %u", len
);
914 idx
< len
&& (eol
= print_txt_line(ndo
, protoname
, "\n\t", pptr
, idx
, len
)) != 0;
919 * Just print the first text line.
921 print_txt_line(ndo
, protoname
, ": ", pptr
, 0, len
);
926 #if (defined(__i386__) || defined(_M_IX86) || defined(__X86__) || defined(__x86_64__) || defined(_M_X64)) || \
927 (defined(__arm__) || defined(_M_ARM) || defined(__aarch64__)) || \
928 (defined(__m68k__) && (!defined(__mc68000__) && !defined(__mc68010__))) || \
929 (defined(__ppc__) || defined(__ppc64__) || defined(_M_PPC) || defined(_ARCH_PPC) || defined(_ARCH_PPC64)) || \
930 (defined(__s390__) || defined(__s390x__) || defined(__zarch__)) || \
933 * The procesor natively handles unaligned loads, so just use memcpy()
934 * and memcmp(), to enable those optimizations.
936 * XXX - are those all the x86 tests we need?
937 * XXX - do we need to worry about ARMv1 through ARMv5, which didn't
938 * support unaligned loads, and, if so, do we need to worry about all
939 * of them, or just some of them, e.g. ARMv5?
940 * XXX - are those the only 68k tests we need not to generated
941 * unaligned accesses if the target is the 68000 or 68010?
942 * XXX - are there any tests we don't need, because some definitions are for
943 * compilers that also predefine the GCC symbols?
944 * XXX - do we need to test for both 32-bit and 64-bit versions of those
945 * architectures in all cases?
949 * The processor doesn't natively handle unaligned loads,
950 * and the compiler might "helpfully" optimize memcpy()
951 * and memcmp(), when handed pointers that would normally
952 * be properly aligned, into sequences that assume proper
955 * Do copies and compares of possibly-unaligned data by
956 * calling routines that wrap memcpy() and memcmp(), to
957 * prevent that optimization.
960 unaligned_memcpy(void *p
, const void *q
, size_t l
)
965 /* As with memcpy(), so with memcmp(). */
967 unaligned_memcmp(const void *p
, const void *q
, size_t l
)
969 return (memcmp(p
, q
, l
));