OVMS3/OVMS.V3/components/duktape/extras/print-alert/duk_print_alert.c

127 lines
3.7 KiB
C

/*
* Duktape 1.x compatible print() and alert() bindings.
*/
#include <stdio.h>
#include <string.h>
#include "duktape.h"
#include "duk_print_alert.h"
#define DUK_PRINT_ALERT_FLUSH /* Flush after stdout/stderr write (Duktape 1.x: yes) */
#undef DUK_PRINT_ALERT_SMALL /* Prefer smaller footprint (but slower and more memory churn) */
#if defined(DUK_PRINT_ALERT_SMALL)
static duk_ret_t duk__print_alert_helper(duk_context *ctx, FILE *fh) {
duk_idx_t nargs;
nargs = duk_get_top(ctx);
/* If argument count is 1 and first argument is a buffer, write the buffer
* as raw data into the file without a newline; this allows exact control
* over stdout/stderr without an additional entrypoint (useful for now).
* Otherwise current print/alert semantics are to ToString() coerce
* arguments, join them with a single space, and append a newline.
*/
if (nargs == 1 && duk_is_buffer_data(ctx, 0)) {
buf = (const duk_uint8_t *) duk_get_buffer_data(ctx, 0, &sz_buf);
fwrite((const void *) buf, 1, (size_t) sz_buf, fh);
} else {
duk_push_string(ctx, " ");
duk_insert(ctx, 0);
duk_concat(ctx, nargs);
fprintf(fh, "%s\n", duk_require_string(ctx, -1));
}
#if defined(DUK_PRINT_ALERT_FLUSH)
fflush(fh);
#endif
return 0;
}
#else
/* Faster, less churn, higher footprint option. */
static duk_ret_t duk__print_alert_helper(duk_context *ctx, FILE *fh) {
duk_idx_t nargs;
const duk_uint8_t *buf;
duk_size_t sz_buf;
const char nl = '\n';
duk_uint8_t buf_stack[256];
nargs = duk_get_top(ctx);
/* If argument count is 1 and first argument is a buffer, write the buffer
* as raw data into the file without a newline; this allows exact control
* over stdout/stderr without an additional entrypoint (useful for now).
* Otherwise current print/alert semantics are to ToString() coerce
* arguments, join them with a single space, and append a newline.
*/
if (nargs == 1 && duk_is_buffer_data(ctx, 0)) {
buf = (const duk_uint8_t *) duk_get_buffer_data(ctx, 0, &sz_buf);
} else if (nargs > 0) {
duk_idx_t i;
duk_size_t sz_str;
const duk_uint8_t *p_str;
duk_uint8_t *p;
sz_buf = (duk_size_t) nargs; /* spaces (nargs - 1) + newline */
for (i = 0; i < nargs; i++) {
(void) duk_to_lstring(ctx, i, &sz_str);
sz_buf += sz_str;
}
if (sz_buf <= sizeof(buf_stack)) {
p = (duk_uint8_t *) buf_stack;
} else {
p = (duk_uint8_t *) duk_push_fixed_buffer(ctx, sz_buf);
}
buf = (const duk_uint8_t *) p;
for (i = 0; i < nargs; i++) {
p_str = (const duk_uint8_t *) duk_get_lstring(ctx, i, &sz_str);
memcpy((void *) p, (const void *) p_str, sz_str);
p += sz_str;
*p++ = (duk_uint8_t) (i == nargs - 1 ? '\n' : ' ');
}
} else {
buf = (const duk_uint8_t *) &nl;
sz_buf = 1;
}
/* 'buf' contains the string to write, 'sz_buf' contains the length
* (which may be zero).
*/
if (sz_buf > 0) {
fwrite((const void *) buf, 1, (size_t) sz_buf, fh);
#if defined(DUK_PRINT_ALERT_FLUSH)
fflush(fh);
#endif
}
return 0;
}
#endif
static duk_ret_t duk__print(duk_context *ctx) {
return duk__print_alert_helper(ctx, stdout);
}
static duk_ret_t duk__alert(duk_context *ctx) {
return duk__print_alert_helper(ctx, stderr);
}
void duk_print_alert_init(duk_context *ctx, duk_uint_t flags) {
(void) flags; /* unused at the moment */
/* XXX: use duk_def_prop_list(). */
duk_push_global_object(ctx);
duk_push_string(ctx, "print");
duk_push_c_function(ctx, duk__print, DUK_VARARGS);
duk_def_prop(ctx, -3, DUK_DEFPROP_HAVE_VALUE | DUK_DEFPROP_SET_WRITABLE | DUK_DEFPROP_SET_CONFIGURABLE);
duk_push_string(ctx, "alert");
duk_push_c_function(ctx, duk__alert, DUK_VARARGS);
duk_def_prop(ctx, -3, DUK_DEFPROP_HAVE_VALUE | DUK_DEFPROP_SET_WRITABLE | DUK_DEFPROP_SET_CONFIGURABLE);
duk_pop(ctx);
}