blob: b9dbff041e64b343dd038e105e3becb621810aa2 [file] [log] [blame]
/*
* Copyright (C) Dmitry Volyntsev
* Copyright (C) NGINX, Inc.
*/
#include <njs_main.h>
#define NJS_CHB_MIN_SIZE 256
void
njs_chb_append0(njs_chb_t *chain, const char *msg, size_t len)
{
u_char *p;
if (len != 0 && !chain->error) {
p = njs_chb_reserve(chain, len);
if (njs_slow_path(p == NULL)) {
return;
}
memcpy(p, msg, len);
njs_chb_written(chain, len);
}
}
u_char *
njs_chb_reserve(njs_chb_t *chain, size_t size)
{
njs_chb_node_t *n;
if (njs_slow_path(size == 0)) {
return NULL;
}
n = chain->last;
if (njs_fast_path(n != NULL && njs_chb_node_room(n) >= size)) {
return n->pos;
}
if (size < NJS_CHB_MIN_SIZE) {
size = NJS_CHB_MIN_SIZE;
}
n = njs_mp_alloc(chain->pool, sizeof(njs_chb_node_t) + size);
if (njs_slow_path(n == NULL)) {
chain->error = 1;
return NULL;
}
n->next = NULL;
n->start = (u_char *) n + sizeof(njs_chb_node_t);
n->pos = n->start;
n->end = n->pos + size;
if (chain->last != NULL) {
chain->last->next = n;
} else {
chain->nodes = n;
}
chain->last = n;
return n->start;
}
void
njs_chb_vsprintf(njs_chb_t *chain, size_t size, const char *fmt, va_list args)
{
u_char *start, *end;
start = njs_chb_reserve(chain, size);
if (njs_slow_path(start == NULL)) {
return;
}
end = njs_vsprintf(start, start + size, fmt, args);
njs_chb_written(chain, end - start);
}
void
njs_chb_sprintf(njs_chb_t *chain, size_t size, const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
njs_chb_vsprintf(chain, size, fmt, args);
va_end(args);
}
/*
* Drains size bytes from the beginning of the chain.
*/
void
njs_chb_drain(njs_chb_t *chain, size_t drain)
{
njs_chb_node_t *n;
n = chain->nodes;
while (n != NULL) {
if (njs_chb_node_size(n) > drain) {
n->start += drain;
return;
}
drain -= njs_chb_node_size(n);
chain->nodes = n->next;
njs_mp_free(chain->pool, n);
n = chain->nodes;
}
chain->last = NULL;
}
/*
* Drops size bytes from the end of the chain.
*/
void
njs_chb_drop(njs_chb_t *chain, size_t drop)
{
size_t size;
njs_chb_node_t *n, *next;
n = chain->last;
if (njs_fast_path(n != NULL && (njs_chb_node_size(n) > drop))) {
n->pos -= drop;
return;
}
n = chain->nodes;
size = njs_chb_size(chain);
if (drop >= size) {
njs_chb_destroy(chain);
njs_chb_init(chain, chain->pool);
return;
}
while (n != NULL) {
size -= njs_chb_node_size(n);
if (size <= drop) {
chain->last = n;
chain->last->pos -= drop - size;
n = chain->last->next;
chain->last->next = NULL;
break;
}
n = n->next;
}
while (n != NULL) {
next = n->next;
njs_mp_free(chain->pool, n);
n = next;
}
}
njs_int_t
njs_chb_join(njs_chb_t *chain, njs_str_t *str)
{
u_char *start;
size_t size;
njs_chb_node_t *n;
if (chain->error) {
return NJS_DECLINED;
}
n = chain->nodes;
if (n == NULL) {
str->length = 0;
str->start = NULL;
return NJS_OK;
}
size = njs_chb_size(chain);
start = njs_mp_alloc(chain->pool, size);
if (njs_slow_path(start == NULL)) {
return NJS_ERROR;
}
str->length = size;
str->start = start;
njs_chb_join_to(chain, start);
return NJS_OK;
}
void
njs_chb_join_to(njs_chb_t *chain, u_char *dst)
{
njs_chb_node_t *n;
n = chain->nodes;
while (n != NULL) {
dst = njs_cpymem(dst, n->start, njs_chb_node_size(n));
n = n->next;
}
}
void
njs_chb_destroy(njs_chb_t *chain)
{
njs_chb_node_t *n, *next;
n = chain->nodes;
while (n != NULL) {
next = n->next;
njs_mp_free(chain->pool, n);
n = next;
}
}