curl/lib/escape.c

113 lines
3.0 KiB
C

/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 2000, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* In order to be useful for every potential user, curl and libcurl are
* dual-licensed under the MPL and the MIT/X-derivate licenses.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the MPL or the MIT/X-derivate
* licenses. You may pick one of these licenses.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
*****************************************************************************/
/* Escape and unescape URL encoding in strings. The functions return a new
* allocated string or NULL if an error occurred. */
#include "setup.h"
#include <ctype.h>
#include <curl/curl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* The last #include file should be: */
#ifdef MALLOCDEBUG
#include "memdebug.h"
#endif
char *curl_escape(const char *string, int length)
{
int alloc = (length?length:(int)strlen(string))+1;
char *ns = malloc(alloc);
unsigned char in;
int newlen = alloc;
int index=0;
length = alloc-1;
while(length--) {
in = *string;
if(' ' == in)
ns[index++] = '+';
else if(!(in >= 'a' && in <= 'z') &&
!(in >= 'A' && in <= 'Z') &&
!(in >= '0' && in <= '9')) {
/* encode it */
newlen += 2; /* the size grows with two, since this'll become a %XX */
if(newlen > alloc) {
alloc *= 2;
ns = realloc(ns, alloc);
if(!ns)
return NULL;
}
sprintf(&ns[index], "%%%02X", in);
index+=3;
}
else {
/* just copy this */
ns[index++]=in;
}
string++;
}
ns[index]=0; /* terminate it */
return ns;
}
char *curl_unescape(const char *string, int length)
{
int alloc = (length?length:(int)strlen(string))+1;
char *ns = malloc(alloc);
unsigned char in;
int index=0;
unsigned int hex;
char querypart=FALSE; /* everything to the right of a '?' letter is
the "query part" where '+' should become ' '.
RFC 2316, section 3.10 */
while(--alloc > 0) {
in = *string;
if(querypart && ('+' == in))
in = ' ';
else if(!querypart && ('?' == in)) {
/* we have "walked in" to the query part */
querypart=TRUE;
}
else if('%' == in) {
/* encoded part */
if(sscanf(string+1, "%02X", &hex)) {
in = hex;
string+=2;
alloc-=2;
}
}
ns[index++] = in;
string++;
}
ns[index]=0; /* terminate it */
return ns;
}