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/*
* Buffer 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 <stdio.h>
#include <string.h>
#include <common/config.h>
#include <common/buffer.h>
#include <common/memory.h>
#include <types/global.h>
struct pool_head *pool2_buffer;
/* perform minimal intializations, report 0 in case of error, 1 if OK. */
int init_buffer()
{
pool2_buffer = create_pool("buffer", sizeof (struct buffer) + global.tune.bufsize, MEM_F_SHARED);
return pool2_buffer != NULL;
}
/* This function writes the string <str> at position <pos> which must be in
* buffer <b>, and moves <end> just after the end of <str>. <b>'s parameters
* <l> and <r> are updated to be valid after the shift. The shift value
* (positive or negative) is returned. If there's no space left, the move is
* not done. The function does not adjust ->o because it does not make sense to
* use it on data scheduled to be sent. For the same reason, it does not make
* sense to call this function on unparsed data, so <orig> is not updated. The
* string length is taken from parameter <len>. If <len> is null, the <str>
* pointer is allowed to be null.
*/
int buffer_replace2(struct buffer *b, char *pos, char *end, const char *str, int len)
{
int delta;
delta = len - (end - pos);
if (bi_end(b) + delta >= b->data + b->size)
return 0; /* no space left */
if (buffer_not_empty(b) &&
bi_end(b) + delta > bo_ptr(b) &&
bo_ptr(b) >= bi_end(b))
return 0; /* no space left before wrapping data */
/* first, protect the end of the buffer */
memmove(end + delta, end, bi_end(b) - end);
/* now, copy str over pos */
if (len)
memcpy(pos, str, len);
b->i += delta;
if (buffer_empty(b))
b->p = b->data;
return delta;
}
/*
* Inserts <str> followed by "\r\n" at position <pos> in buffer <b>. The <len>
* argument informs about the length of string <str> so that we don't have to
* measure it. It does not include the "\r\n". If <str> is NULL, then the buffer
* is only opened for len+2 bytes but nothing is copied in. It may be useful in
* some circumstances. The send limit is *not* adjusted. Same comments as above
* for the valid use cases.
*
* The number of bytes added is returned on success. 0 is returned on failure.
*/
int buffer_insert_line2(struct buffer *b, char *pos, const char *str, int len)
{
int delta;
delta = len + 2;
if (bi_end(b) + delta >= b->data + b->size)
return 0; /* no space left */
if (buffer_not_empty(b) &&
bi_end(b) + delta > bo_ptr(b) &&
bo_ptr(b) >= bi_end(b))
return 0; /* no space left before wrapping data */
/* first, protect the end of the buffer */
memmove(pos + delta, pos, bi_end(b) - pos);
/* now, copy str over pos */
if (len && str) {
memcpy(pos, str, len);
pos[len] = '\r';
pos[len + 1] = '\n';
}
b->i += delta;
return delta;
}
/* This function realigns input data in a possibly wrapping buffer so that it
* becomes contiguous and starts at the beginning of the buffer area. The
* function may only be used when the buffer's output is empty.
*/
void buffer_slow_realign(struct buffer *buf)
{
/* two possible cases :
* - the buffer is in one contiguous block, we move it in-place
* - the buffer is in two blocks, we move it via the swap_buffer
*/
if (buf->i) {
int block1 = buf->i;
int block2 = 0;
if (buf->p + buf->i > buf->data + buf->size) {
/* non-contiguous block */
block1 = buf->data + buf->size - buf->p;
block2 = buf->p + buf->i - (buf->data + buf->size);
}
if (block2)
memcpy(swap_buffer, buf->data, block2);
memmove(buf->data, buf->p, block1);
if (block2)
memcpy(buf->data + block1, swap_buffer, block2);
}
buf->p = buf->data;
}
/* Realigns a possibly non-contiguous buffer by bouncing bytes from source to
* destination. It does not use any intermediate buffer and does the move in
* place, though it will be slower than a simple memmove() on contiguous data,
* so it's desirable to use it only on non-contiguous buffers. No pointers are
* changed, the caller is responsible for that.
*/
void buffer_bounce_realign(struct buffer *buf)
{
int advance, to_move;
char *from, *to;
from = bo_ptr(buf);
advance = buf->data + buf->size - from;
if (!advance)
return;
to_move = buffer_len(buf);
while (to_move) {
char last, save;
last = *from;
to = from + advance;
if (to >= buf->data + buf->size)
to -= buf->size;
while (1) {
save = *to;
*to = last;
last = save;
to_move--;
if (!to_move)
break;
/* check if we went back home after rotating a number of bytes */
if (to == from)
break;
/* if we ended up in the empty area, let's walk to next place. The
* empty area is either between buf->r and from or before from or
* after buf->r.
*/
if (from > bi_end(buf)) {
if (to >= bi_end(buf) && to < from)
break;
} else if (from < bi_end(buf)) {
if (to < from || to >= bi_end(buf))
break;
}
/* we have overwritten a byte of the original set, let's move it */
to += advance;
if (to >= buf->data + buf->size)
to -= buf->size;
}
from++;
if (from >= buf->data + buf->size)
from -= buf->size;
}
}
/*
* Dumps part or all of a buffer.
*/
void buffer_dump(FILE *o, struct buffer *b, int from, int to)
{
fprintf(o, "Dumping buffer %p\n", b);
fprintf(o, " data=%p o=%d i=%d p=%p\n"
" relative: p=0x%04x\n",
b->data, b->o, b->i, b->p, (unsigned int)(b->p - b->data));
fprintf(o, "Dumping contents from byte %d to byte %d\n", from, to);
fprintf(o, " 0 1 2 3 4 5 6 7 8 9 a b c d e f\n");
/* dump hexa */
while (from < to) {
int i;
fprintf(o, " %04x: ", from);
for (i = 0; ((from + i) < to) && (i < 16) ; i++) {
fprintf(o, "%02x ", (unsigned char)b->data[from + i]);
if (((from + i) & 15) == 7)
fprintf(o, "- ");
}
if (to - from < 16) {
int j = 0;
for (j = 0; j < from + 16 - to; j++)
fprintf(o, " ");
if (j > 8)
fprintf(o, " ");
}
fprintf(o, " ");
for (i = 0; (from + i < to) && (i < 16) ; i++) {
fprintf(o, "%c", isprint((int)b->data[from + i]) ? b->data[from + i] : '.') ;
if ((((from + i) & 15) == 15) && ((from + i) != to-1))
fprintf(o, "\n");
}
from += i;
}
fprintf(o, "\n--\n");
fflush(o);
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/