cosmopolitan/third_party/duktape/duk_hbuffer_ops.c

79 lines
2.1 KiB
C

/*
* duk_hbuffer operations such as resizing and inserting/appending data to
* a dynamic buffer.
*/
#include "third_party/duktape/duk_internal.h"
/*
* Resizing
*/
DUK_INTERNAL void duk_hbuffer_resize(duk_hthread *thr, duk_hbuffer_dynamic *buf, duk_size_t new_size) {
void *res;
duk_size_t prev_size;
DUK_ASSERT(thr != NULL);
DUK_ASSERT(buf != NULL);
DUK_ASSERT(DUK_HBUFFER_HAS_DYNAMIC(buf));
DUK_ASSERT(!DUK_HBUFFER_HAS_EXTERNAL(buf));
/*
* Maximum size check
*/
if (new_size > DUK_HBUFFER_MAX_BYTELEN) {
DUK_ERROR_RANGE(thr, "buffer too long");
DUK_WO_NORETURN(return;);
}
/*
* Note: use indirect realloc variant just in case mark-and-sweep
* (finalizers) might resize this same buffer during garbage
* collection.
*/
res = DUK_REALLOC_INDIRECT(thr->heap, duk_hbuffer_get_dynalloc_ptr, (void *) buf, new_size);
if (DUK_LIKELY(res != NULL || new_size == 0)) {
/* 'res' may be NULL if new allocation size is 0. */
DUK_DDD(DUK_DDDPRINT("resized dynamic buffer %p:%ld -> %p:%ld",
(void *) DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(thr->heap, buf),
(long) DUK_HBUFFER_DYNAMIC_GET_SIZE(buf),
(void *) res,
(long) new_size));
/*
* The entire allocated buffer area, regardless of actual used
* size, is kept zeroed in resizes for simplicity. If the buffer
* is grown, zero the new part.
*/
prev_size = DUK_HBUFFER_DYNAMIC_GET_SIZE(buf);
if (new_size > prev_size) {
DUK_ASSERT(new_size - prev_size > 0);
#if defined(DUK_USE_ZERO_BUFFER_DATA)
duk_memzero((void *) ((char *) res + prev_size),
(duk_size_t) (new_size - prev_size));
#endif
}
DUK_HBUFFER_DYNAMIC_SET_SIZE(buf, new_size);
DUK_HBUFFER_DYNAMIC_SET_DATA_PTR(thr->heap, buf, res);
} else {
DUK_ERROR_ALLOC_FAILED(thr);
DUK_WO_NORETURN(return;);
}
DUK_ASSERT(res != NULL || new_size == 0);
}
DUK_INTERNAL void duk_hbuffer_reset(duk_hthread *thr, duk_hbuffer_dynamic *buf) {
DUK_ASSERT(thr != NULL);
DUK_ASSERT(buf != NULL);
DUK_ASSERT(DUK_HBUFFER_HAS_DYNAMIC(buf));
DUK_ASSERT(!DUK_HBUFFER_HAS_EXTERNAL(buf));
duk_hbuffer_resize(thr, buf, 0);
}