blob: f84ab10510e04954104a1b7787af7af5d6bd15c4 [file] [log] [blame]
/*
* Chunk management functions.
*
* Copyright 2000-2012 Willy Tarreau <w@1wt.eu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <ctype.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <common/config.h>
#include <common/chunk.h>
/* trash chunks used for various conversions */
static struct chunk *trash_chunk;
static struct chunk trash_chunk1;
static struct chunk trash_chunk2;
/* trash buffers used for various conversions */
static int trash_size;
static char *trash_buf1;
static char *trash_buf2;
/*
* Returns a pre-allocated and initialized trash chunk that can be used for any
* type of conversion. Two chunks and their respective buffers are alternatively
* returned so that it is always possible to iterate data transformations without
* losing the data being transformed. The blocks are initialized to the size of
* a standard buffer, so they should be enough for everything.
*/
struct chunk *get_trash_chunk(void)
{
char *trash_buf;
if (trash_chunk == &trash_chunk1) {
trash_chunk = &trash_chunk2;
trash_buf = trash_buf2;
}
else {
trash_chunk = &trash_chunk1;
trash_buf = trash_buf1;
}
chunk_init(trash_chunk, trash_buf, trash_size);
return trash_chunk;
}
/* (re)allocates the trash buffers. Returns 0 in case of failure. It is
* possible to call this function multiple times if the trash size changes.
*/
int alloc_trash_buffers(int bufsize)
{
trash_size = bufsize;
trash_buf1 = (char *)realloc(trash_buf1, bufsize);
trash_buf2 = (char *)realloc(trash_buf2, bufsize);
return trash_buf1 && trash_buf2;
}
/*
* Does an snprintf() at the beginning of chunk <chk>, respecting the limit of
* at most chk->size chars. If the chk->len is over, nothing is added. Returns
* the new chunk size, or < 0 in case of failure.
*/
int chunk_printf(struct chunk *chk, const char *fmt, ...)
{
va_list argp;
int ret;
if (!chk->str || !chk->size)
return 0;
va_start(argp, fmt);
ret = vsnprintf(chk->str, chk->size, fmt, argp);
va_end(argp);
chk->len = ret;
if (ret >= chk->size)
ret = -1;
chk->len = ret;
return chk->len;
}
/*
* Does an snprintf() at the end of chunk <chk>, respecting the limit of
* at most chk->size chars. If the chk->len is over, nothing is added. Returns
* the new chunk size.
*/
int chunk_appendf(struct chunk *chk, const char *fmt, ...)
{
va_list argp;
int ret;
if (!chk->str || !chk->size)
return 0;
va_start(argp, fmt);
ret = vsnprintf(chk->str + chk->len, chk->size - chk->len, fmt, argp);
if (ret >= chk->size - chk->len)
/* do not copy anything in case of truncation */
chk->str[chk->len] = 0;
else
chk->len += ret;
va_end(argp);
return chk->len;
}
/*
* Encode chunk <src> into chunk <dst>, respecting the limit of at most
* chk->size chars. Replace non-printable or special chracters with "&#%d;".
* If the chk->len is over, nothing is added. Returns the new chunk size.
*/
int chunk_htmlencode(struct chunk *dst, struct chunk *src)
{
int i, l;
int olen, free;
char c;
olen = dst->len;
for (i = 0; i < src->len; i++) {
free = dst->size - dst->len;
if (!free) {
dst->len = olen;
return dst->len;
}
c = src->str[i];
if (!isascii(c) || !isprint((unsigned char)c) || c == '&' || c == '"' || c == '\'' || c == '<' || c == '>') {
l = snprintf(dst->str + dst->len, free, "&#%u;", (unsigned char)c);
if (free < l) {
dst->len = olen;
return dst->len;
}
dst->len += l;
} else {
dst->str[dst->len] = c;
dst->len++;
}
}
return dst->len;
}
/*
* Encode chunk <src> into chunk <dst>, respecting the limit of at most
* chk->size chars. Replace non-printable or char passed in qc with "<%02X>".
* If the chk->len is over, nothing is added. Returns the new chunk size.
*/
int chunk_asciiencode(struct chunk *dst, struct chunk *src, char qc)
{
int i, l;
int olen, free;
char c;
olen = dst->len;
for (i = 0; i < src->len; i++) {
free = dst->size - dst->len;
if (!free) {
dst->len = olen;
return dst->len;
}
c = src->str[i];
if (!isascii(c) || !isprint((unsigned char)c) || c == '<' || c == '>' || c == qc) {
l = snprintf(dst->str + dst->len, free, "<%02X>", (unsigned char)c);
if (free < l) {
dst->len = olen;
return dst->len;
}
dst->len += l;
} else {
dst->str[dst->len] = c;
dst->len++;
}
}
return dst->len;
}
/* Compares the string in chunk <chk> with the string in <str> which must be
* zero-terminated. Return is the same as with strcmp(). Neither is allowed
* to be null.
*/
int chunk_strcmp(const struct chunk *chk, const char *str)
{
const char *s1 = chk->str;
int len = chk->len;
int diff = 0;
do {
if (--len < 0)
break;
diff = (unsigned char)*(s1++) - (unsigned char)*(str++);
} while (!diff);
return diff;
}
/* Case-insensitively compares the string in chunk <chk> with the string in
* <str> which must be zero-terminated. Return is the same as with strcmp().
* Neither is allowed to be null.
*/
int chunk_strcasecmp(const struct chunk *chk, const char *str)
{
const char *s1 = chk->str;
int len = chk->len;
int diff = 0;
do {
if (--len < 0)
break;
diff = (unsigned char)*s1 - (unsigned char)*str;
if (unlikely(diff)) {
unsigned int l = (unsigned char)*s1;
unsigned int r = (unsigned char)*str;
l -= 'a';
r -= 'a';
if (likely(l <= (unsigned char)'z' - 'a'))
l -= 'a' - 'A';
if (likely(r <= (unsigned char)'z' - 'a'))
r -= 'a' - 'A';
diff = l - r;
}
s1++; str++;
} while (!diff);
return diff;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/