nbase_str.c

来自「Ubuntu packages of security software。 相」· C语言 代码 · 共 247 行

/***************************************************************************
 * nbase_str.c -- string related functings in the nbase library.  These    *
 * were written by [e-mail] .                                   *
 *                                                                         *
 ***********************IMPORTANT NMAP LICENSE TERMS************************
 *                                                                         *
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 * also a registered trademark of Insecure.Com LLC.  This program is free  *
 * software; you may redistribute and/or modify it under the terms of the  *
 * GNU General Public License as published by the Free Software            *
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 *                                                                         *
 ***************************************************************************/

/* $Id: nbase_str.c 6636 2007-12-22 06:32:28Z fyodor $ */

#include "nbase.h"
#include <string.h>
#include <stdarg.h>
#include <stdio.h>

#ifndef HAVE_STRCASESTR
char *strcasestr(const char *haystack, const char *pneedle) {
char buf[512];
unsigned int needlelen;
const char *p;
char *needle, *q, *foundto;

/* Should crash if !pneedle -- this is OK */
if (!*pneedle) return (char *) haystack;
if (!haystack) return NULL;

needlelen = (unsigned int) strlen(pneedle);
 if (needlelen >= sizeof(buf)) {
   needle = (char *) malloc(needlelen + 1);
 } else needle = buf;
 p = pneedle; q = needle;
 while((*q++ = tolower(*p++)))
   ;
 p = haystack - 1; foundto = needle;
 while(*++p) {
   if(tolower(*p) == *foundto) {
     if(!*++foundto) {
       /* Yeah, we found it */
       if (needlelen >= sizeof(buf))
         free(needle);
       return (char *) (p - needlelen + 1);
     }
   } else foundto = needle;
 }
 if (needlelen >= sizeof(buf))
   free(needle);
 return NULL;
}
#endif

int Strncpy(char *dest, const char *src, size_t n) {
  strncpy(dest, src, n);
  if (dest[n-1] == '\0')
    return 0;
  dest[n-1] = '\0';
  return -1;
}

int Vsnprintf(char *s, size_t n, const char *fmt, va_list ap)
{
	int ret;

	ret = vsnprintf(s, n, fmt, ap);

	if (ret < 0 || (unsigned) ret >= n)
		s[n - 1] = '\0';

	return ret;
}

int Snprintf(char *s, size_t n, const char *fmt, ...)
{
	va_list ap;
	int ret;

	va_start(ap, fmt);
	ret = Vsnprintf(s, n, fmt, ap);
	va_end(ap);

	return ret;
}

/* Trivial function that returns nonzero if all characters in str of length strlength are
   printable (as defined by isprint()) */
int stringisprintable(const char *str, int strlength) {
  int i;
  for(i=0; i < strlength; i++)
    if (!isprint((unsigned char) str[i]))
      return 0;

  return 1;
}

/* Convert non-printable characters to replchar in the string */
void replacenonprintable(char *str, int strlength, char replchar) {
  int i;
  for(i=0; i < strlength; i++)
    if (!isprint( (unsigned char) str[i]))
      str[i] = replchar;

  return;
}

/* Returns the position of the last directory separator (slash, also backslash
   on Win32) in a path. Returns -1 if none was found. */
static int find_last_path_separator(const char *path) {
#ifndef WIN32
  const char *PATH_SEPARATORS = "/";
#else
  const char *PATH_SEPARATORS = "\\/";
#endif
  const char *p;

  p = path + strlen(path) - 1;
  while (p >= path) {
    if (strchr(PATH_SEPARATORS, *p) != NULL)
      return p - path;
    p--;
  }

  return -1;
}

/* Returns the directory name part of a path (everything up to the last
   directory separator). If there is no separator, returns ".". If there is only
   one separator and it is the first character, returns "/". Returns NULL on
   error. The returned string must be freed. */
char *path_get_dirname(const char *path) {
  char *result;
  int i;

  i = find_last_path_separator(path);
  if (i == -1)
    return strdup(".");
  if (i == 0)
    return strdup("/");

  result = (char *) malloc(i + 1);
  if (result == NULL)
    return NULL;
  strncpy(result, path, i);
  result[i] = '\0';

  return result;
}

/* Returns the file name part of a path (everything after the last directory
   separator). Returns NULL on error. The returned string must be freed. */
char *path_get_basename(const char *path) {
  int i;

  i = find_last_path_separator(path);

  return strdup(path + i + 1);
}