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Sourcecode: tcpdump version File versions

util.c

/*
 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
 *    The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static const char rcsid[] _U_ =
    "@(#) $Header: /tcpdump/master/tcpdump/util.c,v 1.87.2.3 2003/12/29 22:42:23 hannes Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <tcpdump-stdinc.h>

#include <sys/stat.h>

#include <errno.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include <pcap.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>

#include "interface.h"

/*
 * Print out a filename (or other ascii string).
 * If ep is NULL, assume no truncation check is needed.
 * Return true if truncated.
 */
int
fn_print(register const u_char *s, register const u_char *ep)
{
      register int ret;
      register u_char c;

      ret = 1;                /* assume truncated */
      while (ep == NULL || s < ep) {
            c = *s++;
            if (c == '\0') {
                  ret = 0;
                  break;
            }
            if (!isascii(c)) {
                  c = toascii(c);
                  putchar('M');
                  putchar('-');
            }
            if (!isprint(c)) {
                  c ^= 0x40;  /* DEL to ?, others to alpha */
                  putchar('^');
            }
            putchar(c);
      }
      return(ret);
}

/*
 * Print out a counted filename (or other ascii string).
 * If ep is NULL, assume no truncation check is needed.
 * Return true if truncated.
 */
int
fn_printn(register const u_char *s, register u_int n,
        register const u_char *ep)
{
      register u_char c;

      while (n > 0 && (ep == NULL || s < ep)) {
            n--;
            c = *s++;
            if (!isascii(c)) {
                  c = toascii(c);
                  putchar('M');
                  putchar('-');
            }
            if (!isprint(c)) {
                  c ^= 0x40;  /* DEL to ?, others to alpha */
                  putchar('^');
            }
            putchar(c);
      }
      return (n == 0) ? 0 : 1;
}

/*
 * Print the timestamp
 */
void
ts_print(register const struct timeval *tvp)
{
      register int s;
      struct tm *tm;
      time_t Time;
      static unsigned b_sec;
      static unsigned b_usec;

      switch(tflag) {
      case 1: /* Default */
            s = (tvp->tv_sec + thiszone) % 86400;
            (void)printf("%02d:%02d:%02d.%06u ",
                       s / 3600, (s % 3600) / 60, s % 60,
                       (unsigned)tvp->tv_usec);
            break;
      case -1: /* Unix timeval style */
            (void)printf("%u.%06u ",
                       (unsigned)tvp->tv_sec,
                       (unsigned)tvp->tv_usec);
            break;
      case -2:
            if (b_sec == 0) {
                  printf("000000 ");
            } else {
                  int d_usec = tvp->tv_usec - b_usec;
                  int d_sec = tvp->tv_sec - b_sec;

                  while (d_usec < 0) {
                        d_usec += 1000000;
                        d_sec--;
                  }
                  if (d_sec)
                        printf("%d. ", d_sec);
                  printf("%06d ", d_usec);
            }
            b_sec = tvp->tv_sec;
            b_usec = tvp->tv_usec;
            break;
      case -3: /* Default + Date*/
            s = (tvp->tv_sec + thiszone) % 86400;
            Time = (tvp->tv_sec + thiszone) - s;
            tm = gmtime (&Time);
            if (!tm)
                  printf("Date fail  ");
            else
                  printf("%04d-%02d-%02d ",
                           tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday);
            printf("%02d:%02d:%02d.%06u ",
                     s / 3600, (s % 3600) / 60, s % 60, (unsigned)tvp->tv_usec);
            break;
      }
}

/*
 * Print a relative number of seconds (e.g. hold time, prune timer)
 * in the form 5m1s.  This does no truncation, so 32230861 seconds
 * is represented as 1y1w1d1h1m1s.
 */
void
relts_print(int secs)
{
      static const char *lengths[] = {"y", "w", "d", "h", "m", "s"};
      static const int seconds[] = {31536000, 604800, 86400, 3600, 60, 1};
      const char **l = lengths;
      const int *s = seconds;

      if (secs == 0) {
            (void)printf("0s");
            return;
      }
      if (secs < 0) {
            (void)printf("-");
            secs = -secs;
      }
      while (secs > 0) {
            if (secs >= *s) {
                  (void)printf("%d%s", secs / *s, *l);
                  secs -= (secs / *s) * *s;
            }
            s++;
            l++;
      }
}

/*
 *  this is a generic routine for printing unknown data;
 *  we pass on the linefeed plus indentation string to
 *  get a proper output - returns 0 on error
 */

int
print_unknown_data(const u_char *cp,const char *ident,int len)
{
        hex_print(ident,cp,len);
      return(1); /* everything is ok */
}

/*
 * Convert a token value to a string; use "fmt" if not found.
 */
const char *
tok2str(register const struct tok *lp, register const char *fmt,
      register int v)
{
      static char buf[128];

      while (lp->s != NULL) {
            if (lp->v == v)
                  return (lp->s);
            ++lp;
      }
      if (fmt == NULL)
            fmt = "#%d";
      (void)snprintf(buf, sizeof(buf), fmt, v);
      return (buf);
}

/*
 * Convert a bit token value to a string; use "fmt" if not found.
 * this is useful for parsing bitfields, the output strings are comma seperated
 */
char *
bittok2str(register const struct tok *lp, register const char *fmt,
      register int v)
{
        static char buf[256]; /* our stringbuffer */
        int buflen=0;
        register int rotbit; /* this is the bit we rotate through all bitpositions */
        register int tokval;

      while (lp->s != NULL) {
            tokval=lp->v;   /* load our first value */
            rotbit=1;
            while (rotbit != 0) {
                /*
                 * lets AND the rotating bit with our token value
                 * and see if we have got a match
                 */
            if (tokval == (v&rotbit)) {
                    /* ok we have found something */
                    buflen+=snprintf(buf+buflen, sizeof(buf)-buflen, "%s, ",lp->s);
                    break;
                }
                rotbit=rotbit<<1; /* no match - lets shift and try again */
            }
            lp++;
      }

        if (buflen != 0) { /* did we find anything */
            /* yep, set the the trailing zero 2 bytes before to eliminate the last comma & whitespace */
            buf[buflen-2] = '\0';
            return (buf);
        }
        else {
            /* bummer - lets print the "unknown" message as advised in the fmt string if we got one */
            if (fmt == NULL)
            fmt = "#%d";
            (void)snprintf(buf, sizeof(buf), fmt, v);
            return (buf);
        }
}

/*
 * Convert a value to a string using an array; the macro
 * tok2strary() in <interface.h> is the public interface to
 * this function and ensures that the second argument is
 * correct for bounds-checking.
 */
const char *
tok2strary_internal(register const char **lp, int n, register const char *fmt,
      register int v)
{
      static char buf[128];

      if (v >= 0 && v < n && lp[v] != NULL)
            return lp[v];
      if (fmt == NULL)
            fmt = "#%d";
      (void)snprintf(buf, sizeof(buf), fmt, v);
      return (buf);
}

/*
 * Convert a 32-bit netmask to prefixlen if possible
 * the function returns the prefix-len; if plen == -1
 * then conversion was not possible;
 */

int
mask2plen (u_int32_t mask)
{
      u_int32_t bitmasks[33] = {
            0x00000000,
            0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
            0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
            0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
            0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
            0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
            0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
            0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
            0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff
      };
      int prefix_len = 32;

      /* let's see if we can transform the mask into a prefixlen */
      while (prefix_len >= 0) {
            if (bitmasks[prefix_len] == mask)
                  break;
            prefix_len--;
      }
      return (prefix_len);
}

/* VARARGS */
void
error(const char *fmt, ...)
{
      va_list ap;

      (void)fprintf(stderr, "%s: ", program_name);
      va_start(ap, fmt);
      (void)vfprintf(stderr, fmt, ap);
      va_end(ap);
      if (*fmt) {
            fmt += strlen(fmt);
            if (fmt[-1] != '\n')
                  (void)fputc('\n', stderr);
      }
      exit(1);
      /* NOTREACHED */
}

/* VARARGS */
void
warning(const char *fmt, ...)
{
      va_list ap;

      (void)fprintf(stderr, "%s: WARNING: ", program_name);
      va_start(ap, fmt);
      (void)vfprintf(stderr, fmt, ap);
      va_end(ap);
      if (*fmt) {
            fmt += strlen(fmt);
            if (fmt[-1] != '\n')
                  (void)fputc('\n', stderr);
      }
}

/*
 * Copy arg vector into a new buffer, concatenating arguments with spaces.
 */
char *
copy_argv(register char **argv)
{
      register char **p;
      register u_int len = 0;
      char *buf;
      char *src, *dst;

      p = argv;
      if (*p == 0)
            return 0;

      while (*p)
            len += strlen(*p++) + 1;

      buf = (char *)malloc(len);
      if (buf == NULL)
            error("copy_argv: malloc");

      p = argv;
      dst = buf;
      while ((src = *p++) != NULL) {
            while ((*dst++ = *src++) != '\0')
                  ;
            dst[-1] = ' ';
      }
      dst[-1] = '\0';

      return buf;
}

/*
 * On Windows, we need to open the file in binary mode, so that
 * we get all the bytes specified by the size we get from "fstat()".
 * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
 * we define it as 0 if it's not defined, so it does nothing.
 */
#ifndef O_BINARY
#define O_BINARY  0
#endif

char *
read_infile(char *fname)
{
      register int i, fd, cc;
      register char *cp;
      struct stat buf;

      fd = open(fname, O_RDONLY|O_BINARY);
      if (fd < 0)
            error("can't open %s: %s", fname, pcap_strerror(errno));

      if (fstat(fd, &buf) < 0)
            error("can't stat %s: %s", fname, pcap_strerror(errno));

      cp = malloc((u_int)buf.st_size + 1);
      if (cp == NULL)
            error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
                  fname, pcap_strerror(errno));
      cc = read(fd, cp, (u_int)buf.st_size);
      if (cc < 0)
            error("read %s: %s", fname, pcap_strerror(errno));
      if (cc != buf.st_size)
            error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);

      close(fd);
      /* replace "# comment" with spaces */
      for (i = 0; i < cc; i++) {
            if (cp[i] == '#')
                  while (i < cc && cp[i] != '\n')
                        cp[i++] = ' ';
      }
      cp[cc] = '\0';
      return (cp);
}

void
safeputs(const char *s)
{
      while (*s) {
            safeputchar(*s);
            s++;
      }
}

void
safeputchar(int c)
{
      unsigned char ch;

      ch = (unsigned char)(c & 0xff);
      if (ch < 0x80 && isprint(ch))
            printf("%c", ch);
      else
            printf("\\%03o", ch);
}

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