duktape-1.5.2/src-separate/duk_api_buffer.c

Go to the documentation of this file.

/*
 *  Buffer
 */
 
#include "duk_internal.h"
 
DUK_EXTERNAL void *duk_resize_buffer(duk_context *ctx, duk_idx_t index, duk_size_t new_size) {
    duk_hthread *thr = (duk_hthread *) ctx;
    duk_hbuffer_dynamic *h;
 
    DUK_ASSERT_CTX_VALID(ctx);
 
    h = (duk_hbuffer_dynamic *) duk_require_hbuffer(ctx, index);
    DUK_ASSERT(h != NULL);
 
    if (!(DUK_HBUFFER_HAS_DYNAMIC(h) && !DUK_HBUFFER_HAS_EXTERNAL(h))) {
        DUK_ERROR_TYPE(thr, DUK_STR_WRONG_BUFFER_TYPE);
    }
 
    /* maximum size check is handled by callee */
    duk_hbuffer_resize(thr, h, new_size);
 
    return DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(thr->heap, h);
}
 
DUK_EXTERNAL void *duk_steal_buffer(duk_context *ctx, duk_idx_t index, duk_size_t *out_size) {
    duk_hthread *thr = (duk_hthread *) ctx;
    duk_hbuffer_dynamic *h;
    void *ptr;
    duk_size_t sz;
 
    DUK_ASSERT(ctx != NULL);
 
    h = (duk_hbuffer_dynamic *) duk_require_hbuffer(ctx, index);
    DUK_ASSERT(h != NULL);
 
    if (!(DUK_HBUFFER_HAS_DYNAMIC(h) && !DUK_HBUFFER_HAS_EXTERNAL(h))) {
        DUK_ERROR_TYPE(thr, DUK_STR_WRONG_BUFFER_TYPE);
    }
 
    /* Forget the previous allocation, setting size to 0 and alloc to
     * NULL.  Caller is responsible for freeing the previous allocation.
     * Getting the allocation and clearing it is done in the same API
     * call to avoid any chance of a realloc.
     */
    ptr = DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(thr->heap, h);
    sz = DUK_HBUFFER_DYNAMIC_GET_SIZE(h);
    if (out_size) {
        *out_size = sz;
    }
    DUK_HBUFFER_DYNAMIC_SET_DATA_PTR_NULL(thr->heap, h);
    DUK_HBUFFER_DYNAMIC_SET_SIZE(h, 0);
 
    return ptr;
}
 
DUK_EXTERNAL void duk_config_buffer(duk_context *ctx, duk_idx_t index, void *ptr, duk_size_t len) {
    duk_hthread *thr = (duk_hthread *) ctx;
    duk_hbuffer_external *h;
 
    DUK_ASSERT(ctx != NULL);
 
    h = (duk_hbuffer_external *) duk_require_hbuffer(ctx, index);
    DUK_ASSERT(h != NULL);
 
    if (!DUK_HBUFFER_HAS_EXTERNAL(h)) {
        DUK_ERROR_TYPE(thr, DUK_STR_WRONG_BUFFER_TYPE);
    }
    DUK_ASSERT(DUK_HBUFFER_HAS_DYNAMIC(h));
 
    DUK_HBUFFER_EXTERNAL_SET_DATA_PTR(thr->heap, h, ptr);
    DUK_HBUFFER_EXTERNAL_SET_SIZE(h, len);
}