mpv/player/javascript.c

1250 lines
39 KiB
C

/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <math.h>
#include <stdint.h>
#include <mujs.h>
#include "osdep/io.h"
#include "mpv_talloc.h"
#include "common/common.h"
#include "options/m_property.h"
#include "common/msg.h"
#include "common/msg_control.h"
#include "common/stats.h"
#include "options/m_option.h"
#include "input/input.h"
#include "options/path.h"
#include "misc/bstr.h"
#include "osdep/timer.h"
#include "osdep/threads.h"
#include "stream/stream.h"
#include "sub/osd.h"
#include "core.h"
#include "command.h"
#include "client.h"
#include "libmpv/client.h"
// List of builtin modules and their contents as strings.
// All these are generated from player/javascript/*.js
static const char *const builtin_files[][3] = {
{"@/defaults.js",
# include "player/javascript/defaults.js.inc"
},
{0}
};
// Represents a loaded script. Each has its own js state.
struct script_ctx {
const char *filename;
const char *path; // NULL if single file
struct mpv_handle *client;
struct MPContext *mpctx;
struct mp_log *log;
char *last_error_str;
size_t js_malloc_size;
struct stats_ctx *stats;
};
static struct script_ctx *jctx(js_State *J)
{
return (struct script_ctx *)js_getcontext(J);
}
static mpv_handle *jclient(js_State *J)
{
return jctx(J)->client;
}
static void pushnode(js_State *J, mpv_node *node);
static void makenode(void *ta_ctx, mpv_node *dst, js_State *J, int idx);
static int jsL_checkint(js_State *J, int idx);
static uint64_t jsL_checkuint64(js_State *J, int idx);
/**********************************************************************
* conventions, MuJS notes and vm errors
*********************************************************************/
// - push_foo functions are called from C and push a value to the vm stack.
//
// - JavaScript C functions are code which the vm can call as a js function.
// By convention, script_bar and script__baz are js C functions. The former
// is exposed to end users as bar, and _baz is for internal use.
//
// - js C functions get a fresh vm stack with their arguments, and may
// manipulate their stack as they see fit. On exit, the vm considers the
// top value of their stack as their return value, and GC the rest.
//
// - js C function's stack[0] is "this", and the rest (1, 2, ...) are the args.
// On entry the stack has at least the number of args defined for the func,
// padded with undefined if called with less, or bigger if called with more.
//
// - Almost all vm APIs (js_*) may throw an error - a longjmp to the last
// recovery/catch point, which could skip releasing resources. This includes
// js_try itself(!), except at the outer-most [1] js_try which is always
// entering the try part (and the catch part if the try part throws).
// The assumption should be that anything can throw and needs careful setup.
// One such automated setup is the autofree mechanism. Details later.
//
// - Unless named s_foo, all the functions at this file (inc. init) which
// touch the vm may throw, but either cleanup resources regardless (mostly
// autofree) or leave allocated resources on caller-provided talloc context
// which the caller should release, typically with autofree (e.g. makenode).
//
// - Functions named s_foo (safe foo) never throw if called at the outer-most
// try-levels, or, inside JS C functions - never throw after allocating.
// If they didn't throw then they return 0 on success, 1 on js-errors.
//
// [1] In practice the N outer-most (nested) tries are guaranteed to enter the
// try/carch code, where N is the mujs try-stack size (64 with mujs 1.1.3).
// But because we can't track try-level at (called-back) JS C functions,
// it's only guaranteed when we know we're near the outer-most try level.
/**********************************************************************
* mpv scripting API error handling
*********************************************************************/
// - Errors may be thrown on some cases - the reason is at the exception.
//
// - Some APIs also set last error which can be fetched with mp.last_error(),
// where empty string (false-y) is success, or an error string otherwise.
//
// - The rest of the APIs are guaranteed to return undefined on error or a
// true-thy value on success and may or may not set last error.
//
// - push_success, push_failure, push_status and pushed_error set last error.
// iserr as true indicates an error, and if so, str may indicate a reason.
// Internally ctx->last_error_str is never NULL, and empty indicates success.
static void set_last_error(struct script_ctx *ctx, bool iserr, const char *str)
{
ctx->last_error_str[0] = 0;
if (!iserr)
return;
if (!str || !str[0])
str = "Error";
ctx->last_error_str = talloc_strdup_append(ctx->last_error_str, str);
}
// For use only by wrappers at defaults.js.
// arg: error string. Use empty string to indicate success.
static void script__set_last_error(js_State *J)
{
const char *e = js_tostring(J, 1);
set_last_error(jctx(J), e[0], e);
}
// mp.last_error() . args: none. return the last error without modifying it.
static void script_last_error(js_State *J)
{
js_pushstring(J, jctx(J)->last_error_str);
}
// Generic success for APIs which don't return an actual value.
static void push_success(js_State *J)
{
set_last_error(jctx(J), 0, NULL);
js_pushboolean(J, true);
}
// Doesn't (intentionally) throw. Just sets last_error and pushes undefined
static void push_failure(js_State *J, const char *str)
{
set_last_error(jctx(J), 1, str);
js_pushundefined(J);
}
// Most of the scripting APIs are either sending some values and getting status
// code in return, or requesting some value while providing a default in case an
// error happened. These simplify the C code for that and always set last_error.
static void push_status(js_State *J, int err)
{
if (err >= 0) {
push_success(J);
} else {
push_failure(J, mpv_error_string(err));
}
}
// If err is success then return 0, else push the item at def and return 1
static bool pushed_error(js_State *J, int err, int def)
{
bool iserr = err < 0;
set_last_error(jctx(J), iserr, iserr ? mpv_error_string(err) : NULL);
if (!iserr)
return false;
js_copy(J, def);
return true;
}
/**********************************************************************
* Autofree - care-free resource deallocation on vm errors, and otherwise
*********************************************************************/
// - Autofree (af) functions are called with a talloc context argument which is
// freed after the function exits - either normally or because it threw an
// error, on the latter case it then re-throws the error after the cleanup.
//
// Autofree js C functions should have an additional void* talloc arg and
// inserted into the vm using af_newcfunction, but otherwise used normally.
//
// To wrap an autofree function af_TARGET in C:
// 1. Create a wrapper s_TARGET which does this:
// if (js_try(J))
// return 1;
// *af = talloc_new(NULL);
// af_TARGET(J, ..., *af);
// js_endtry(J);
// return 0;
// 2. Use s_TARGET like so (frees if allocated, throws if {s,af}_TARGET threw):
// void *af = NULL;
// int r = s_TARGET(J, ..., &af); // use J, af where the callee expects.
// talloc_free(af);
// if (r)
// js_throw(J);
//
// The reason that the allocation happens inside try/catch is that js_try
// itself can throw (if it runs out of try-stack) and therefore the code
// inside the try part is not reached - but neither is the catch part(!),
// and instead it throws to the next outer catch - but before we've allocated
// anything, hence no leaks on such case. If js_try did get entered, then the
// allocation happened, and then if af_TARGET threw then s_TARGET will catch
// it (and return 1) and we'll free if afterwards.
// add_af_file, add_af_dir, add_af_mpv_alloc take a valid FILE*/DIR*/char* value
// respectively, and fclose/closedir/mpv_free it when the parent is freed.
static void destruct_af_file(void *p)
{
fclose(*(FILE**)p);
}
static void add_af_file(void *parent, FILE *f)
{
FILE **pf = talloc(parent, FILE*);
*pf = f;
talloc_set_destructor(pf, destruct_af_file);
}
static void destruct_af_dir(void *p)
{
closedir(*(DIR**)p);
}
static void add_af_dir(void *parent, DIR *d)
{
DIR **pd = talloc(parent, DIR*);
*pd = d;
talloc_set_destructor(pd, destruct_af_dir);
}
static void destruct_af_mpv_alloc(void *p)
{
mpv_free(*(char**)p);
}
static void add_af_mpv_alloc(void *parent, char *ma)
{
char **p = talloc(parent, char*);
*p = ma;
talloc_set_destructor(p, destruct_af_mpv_alloc);
}
static void destruct_af_mpv_node(void *p)
{
mpv_free_node_contents((mpv_node*)p); // does nothing for MPV_FORMAT_NONE
}
// returns a new zeroed allocated struct mpv_node, and free it and its content
// when the parent is freed.
static mpv_node *new_af_mpv_node(void *parent)
{
mpv_node *p = talloc_zero(parent, mpv_node); // .format == MPV_FORMAT_NONE
talloc_set_destructor(p, destruct_af_mpv_node);
return p;
}
// Prototype for autofree functions which can be called from inside the vm.
typedef void (*af_CFunction)(js_State*, void*);
// safely run autofree js c function directly
static int s_run_af_jsc(js_State *J, af_CFunction fn, void **af)
{
if (js_try(J))
return 1;
*af = talloc_new(NULL);
fn(J, *af);
js_endtry(J);
return 0;
}
// The trampoline function through which all autofree functions are called from
// inside the vm. Obtains the target function address and autofree-call it.
static void script__autofree(js_State *J)
{
// The target function is at the "af_" property of this function instance.
js_currentfunction(J);
js_getproperty(J, -1, "af_");
af_CFunction fn = (af_CFunction)js_touserdata(J, -1, "af_fn");
js_pop(J, 2);
void *af = NULL;
int r = s_run_af_jsc(J, fn, &af);
talloc_free(af);
if (r)
js_throw(J);
}
// Identical to js_newcfunction, but the function is inserted with an autofree
// wrapper, and its prototype should have the additional af argument.
static void af_newcfunction(js_State *J, af_CFunction fn, const char *name,
int length)
{
js_newcfunction(J, script__autofree, name, length);
js_pushnull(J); // a prototype for the userdata object
js_newuserdata(J, "af_fn", fn, NULL); // uses a "af_fn" verification tag
js_defproperty(J, -2, "af_", JS_READONLY | JS_DONTENUM | JS_DONTCONF);
}
/**********************************************************************
* Initialization and file loading
*********************************************************************/
static const char *get_builtin_file(const char *name)
{
for (int n = 0; builtin_files[n][0]; n++) {
if (strcmp(builtin_files[n][0], name) == 0)
return builtin_files[n][1];
}
return NULL;
}
// Push up to limit bytes of file fname: from builtin_files, else from the OS.
static void af_push_file(js_State *J, const char *fname, int limit, void *af)
{
char *filename = mp_get_user_path(af, jctx(J)->mpctx->global, fname);
MP_VERBOSE(jctx(J), "Reading file '%s'\n", filename);
if (limit < 0)
limit = INT_MAX - 1;
const char *builtin = get_builtin_file(filename);
if (builtin) {
js_pushlstring(J, builtin, MPMIN(limit, strlen(builtin)));
return;
}
// mp.utils.read_file allows partial read up to limit which results in
// error for stream_read_file if the file is larger than limit, so use
// STREAM_ALLOW_PARTIAL_READ to allow reading returning partial results.
// Additionally, disable error logging by stream since the exception
// can be caught and handled by a JS script.
int flags = STREAM_READ_FILE_FLAGS_DEFAULT | STREAM_ALLOW_PARTIAL_READ |
STREAM_SILENT;
bstr data = stream_read_file2(filename, af, flags,
jctx(J)->mpctx->global, limit);
if (data.start) {
js_pushlstring(J, data.start, data.len);
} else {
js_error(J, "cannot open file: '%s'", filename);
}
}
// Safely run af_push_file.
static int s_push_file(js_State *J, const char *fname, int limit, void **af)
{
if (js_try(J))
return 1;
*af = talloc_new(NULL);
af_push_file(J, fname, limit, *af);
js_endtry(J);
return 0;
}
// Called directly, push up to limit bytes of file fname (from builtin/os).
static void push_file_content(js_State *J, const char *fname, int limit)
{
void *af = NULL;
int r = s_push_file(J, fname, limit, &af);
talloc_free(af);
if (r)
js_throw(J);
}
// utils.read_file(..). args: fname [,max]. returns [up to max] bytes as string.
static void script_read_file(js_State *J)
{
int limit = js_isundefined(J, 2) ? -1 : jsL_checkint(J, 2);
push_file_content(J, js_tostring(J, 1), limit);
}
// Runs a file with the caller's this, leaves the stack as is.
static void run_file(js_State *J, const char *fname)
{
MP_VERBOSE(jctx(J), "Loading file %s\n", fname);
push_file_content(J, fname, -1);
js_loadstring(J, fname, js_tostring(J, -1));
js_copy(J, 0); // use the caller's this
js_call(J, 0);
js_pop(J, 2); // result, file content
}
// The spec defines .name and .message for Error objects. Most engines also set
// a very convenient .stack = name + message + trace, but MuJS instead sets
// .stackTrace = trace only. Normalize by adding such .stack if required.
// Run this before anything such that we can get traces on any following errors.
static const char *norm_err_proto_js = "\
if (Error().stackTrace && !Error().stack) {\
Object.defineProperty(Error.prototype, 'stack', {\
get: function() {\
return this.name + ': ' + this.message + this.stackTrace;\
}\
});\
}\
";
static void add_functions(js_State*, struct script_ctx*);
// args: none. called as script, setup and run the main script
static void script__run_script(js_State *J)
{
js_loadstring(J, "@/norm_err.js", norm_err_proto_js);
js_copy(J, 0);
js_pcall(J, 0);
struct script_ctx *ctx = jctx(J);
add_functions(J, ctx);
run_file(J, "@/defaults.js");
run_file(J, ctx->filename); // the main file to run
if (!js_hasproperty(J, 0, "mp_event_loop") || !js_iscallable(J, -1))
js_error(J, "no event loop function");
js_copy(J, 0);
js_call(J, 0); // mp_event_loop
}
// Safely set last error from stack top: stack trace or toString or generic.
// May leave items on stack - the caller should detect and pop if it cares.
static void s_top_to_last_error(struct script_ctx *ctx, js_State *J)
{
set_last_error(ctx, 1, "unknown error");
if (js_try(J))
return;
if (js_isobject(J, -1))
js_hasproperty(J, -1, "stack"); // fetches it if exists
set_last_error(ctx, 1, js_tostring(J, -1));
js_endtry(J);
}
// MuJS can report warnings through this.
static void report_handler(js_State *J, const char *msg)
{
MP_WARN(jctx(J), "[JS] %s\n", msg);
}
// Safely setup the js vm for calling run_script.
static int s_init_js(js_State *J, struct script_ctx *ctx)
{
if (js_try(J))
return 1;
js_setcontext(J, ctx);
js_setreport(J, report_handler);
js_newcfunction(J, script__run_script, "run_script", 0);
js_pushglobal(J); // 'this' for script__run_script
js_endtry(J);
return 0;
}
static void *mp_js_alloc(void *actx, void *ptr, int size_)
{
if (size_ < 0)
return NULL;
struct script_ctx* ctx = actx;
size_t size = size_, osize = 0;
if (ptr) // free/realloc
osize = ta_get_size(ptr);
void *ret = talloc_realloc_size(actx, ptr, size);
if (!size || ret) { // free / successful realloc/malloc
ctx->js_malloc_size = ctx->js_malloc_size - osize + size;
stats_size_value(ctx->stats, "mem", ctx->js_malloc_size);
}
return ret;
}
/**********************************************************************
* Initialization - booting the script
*********************************************************************/
// s_load_javascript: (entry point) creates the js vm, runs the script, returns
// on script exit or uncaught js errors. Never throws.
// script__run_script: - loads the built in functions and vars into the vm
// - runs the default file[s] and the main script file
// - calls mp_event_loop, returns on script-exit or throws.
//
// Note: init functions don't need autofree. They can use ctx as a talloc
// context and free normally. If they throw - ctx is freed right afterwards.
static int s_load_javascript(struct mp_script_args *args)
{
struct script_ctx *ctx = talloc_ptrtype(NULL, ctx);
*ctx = (struct script_ctx) {
.client = args->client,
.mpctx = args->mpctx,
.log = args->log,
.last_error_str = talloc_strdup(ctx, "Cannot initialize JavaScript"),
.filename = args->filename,
.path = args->path,
.js_malloc_size = 0,
.stats = stats_ctx_create(ctx, args->mpctx->global,
mp_tprintf(80, "script/%s", mpv_client_name(args->client))),
};
stats_register_thread_cputime(ctx->stats, "cpu");
js_Alloc alloc_fn = NULL;
void *actx = NULL;
if (args->mpctx->opts->js_memory_report) {
alloc_fn = mp_js_alloc;
actx = ctx;
}
int r = -1;
js_State *J = js_newstate(alloc_fn, actx, 0);
if (!J || s_init_js(J, ctx))
goto error_out;
set_last_error(ctx, 0, NULL);
if (js_pcall(J, 0)) { // script__run_script
s_top_to_last_error(ctx, J);
goto error_out;
}
r = 0;
error_out:
if (r)
MP_FATAL(ctx, "%s\n", ctx->last_error_str);
if (J)
js_freestate(J);
talloc_free(ctx);
return r;
}
/**********************************************************************
* Main mp.* scripting APIs and helpers
*********************************************************************/
// Return the index in opts of stack[idx] (or of def if undefined), else throws.
static int checkopt(js_State *J, int idx, const char *def, const char *opts[],
const char *desc)
{
const char *opt = js_isundefined(J, idx) ? def : js_tostring(J, idx);
for (int i = 0; opts[i]; i++) {
if (strcmp(opt, opts[i]) == 0)
return i;
}
js_error(J, "Invalid %s '%s'", desc, opt);
}
// args: level as string and a variable numbers of args to print. adds final \n
static void script_log(js_State *J)
{
const char *level = js_tostring(J, 1);
int msgl = mp_msg_find_level(level);
if (msgl < 0)
js_error(J, "Invalid log level '%s'", level);
struct mp_log *log = jctx(J)->log;
for (int top = js_gettop(J), i = 2; i < top; i++)
mp_msg(log, msgl, (i == 2 ? "%s" : " %s"), js_tostring(J, i));
mp_msg(log, msgl, "\n");
push_success(J);
}
static void script_find_config_file(js_State *J, void *af)
{
const char *fname = js_tostring(J, 1);
char *path = mp_find_config_file(af, jctx(J)->mpctx->global, fname);
if (path) {
js_pushstring(J, path);
} else {
push_failure(J, "not found");
}
}
static void script__request_event(js_State *J)
{
const char *event = js_tostring(J, 1);
bool enable = js_toboolean(J, 2);
for (int n = 0; n < 256; n++) {
// some n's may be missing ("holes"), returning NULL
const char *name = mpv_event_name(n);
if (name && strcmp(name, event) == 0) {
push_status(J, mpv_request_event(jclient(J), n, enable));
return;
}
}
push_failure(J, "Unknown event name");
}
static void script_enable_messages(js_State *J)
{
const char *level = js_tostring(J, 1);
int e = mpv_request_log_messages(jclient(J), level);
if (e == MPV_ERROR_INVALID_PARAMETER)
js_error(J, "Invalid log level '%s'", level);
push_status(J, e);
}
// args - command [with arguments] as string
static void script_command(js_State *J)
{
push_status(J, mpv_command_string(jclient(J), js_tostring(J, 1)));
}
// args: strings of command and then variable number of arguments
static void script_commandv(js_State *J)
{
const char *argv[MP_CMD_MAX_ARGS + 1];
int length = js_gettop(J) - 1;
if (length >= MP_ARRAY_SIZE(argv))
js_error(J, "Too many arguments");
for (int i = 0; i < length; i++)
argv[i] = js_tostring(J, 1 + i);
argv[length] = NULL;
push_status(J, mpv_command(jclient(J), argv));
}
// args: name, string value
static void script_set_property(js_State *J)
{
int e = mpv_set_property_string(jclient(J), js_tostring(J, 1),
js_tostring(J, 2));
push_status(J, e);
}
// args: name, boolean
static void script_set_property_bool(js_State *J)
{
int v = js_toboolean(J, 2);
int e = mpv_set_property(jclient(J), js_tostring(J, 1), MPV_FORMAT_FLAG, &v);
push_status(J, e);
}
// args: name [,def]
static void script_get_property_number(js_State *J)
{
double result;
const char *name = js_tostring(J, 1);
int e = mpv_get_property(jclient(J), name, MPV_FORMAT_DOUBLE, &result);
if (!pushed_error(J, e, 2))
js_pushnumber(J, result);
}
// args: name, native value
static void script_set_property_native(js_State *J, void *af)
{
mpv_node node;
makenode(af, &node, J, 2);
mpv_handle *h = jclient(J);
int e = mpv_set_property(h, js_tostring(J, 1), MPV_FORMAT_NODE, &node);
push_status(J, e);
}
// args: name [,def]
static void script_get_property(js_State *J, void *af)
{
mpv_handle *h = jclient(J);
char *res = NULL;
int e = mpv_get_property(h, js_tostring(J, 1), MPV_FORMAT_STRING, &res);
if (e >= 0)
add_af_mpv_alloc(af, res);
if (!pushed_error(J, e, 2))
js_pushstring(J, res);
}
// args: name
static void script_del_property(js_State *J)
{
int e = mpv_del_property(jclient(J), js_tostring(J, 1));
push_status(J, e);
}
// args: name [,def]
static void script_get_property_bool(js_State *J)
{
int result;
mpv_handle *h = jclient(J);
int e = mpv_get_property(h, js_tostring(J, 1), MPV_FORMAT_FLAG, &result);
if (!pushed_error(J, e, 2))
js_pushboolean(J, result);
}
// args: name, number
static void script_set_property_number(js_State *J)
{
double v = js_tonumber(J, 2);
mpv_handle *h = jclient(J);
int e = mpv_set_property(h, js_tostring(J, 1), MPV_FORMAT_DOUBLE, &v);
push_status(J, e);
}
// args: name [,def]
static void script_get_property_native(js_State *J, void *af)
{
const char *name = js_tostring(J, 1);
mpv_handle *h = jclient(J);
mpv_node *presult_node = new_af_mpv_node(af);
int e = mpv_get_property(h, name, MPV_FORMAT_NODE, presult_node);
if (!pushed_error(J, e, 2))
pushnode(J, presult_node);
}
// args: name [,def]
static void script_get_property_osd(js_State *J, void *af)
{
const char *name = js_tostring(J, 1);
mpv_handle *h = jclient(J);
char *res = NULL;
int e = mpv_get_property(h, name, MPV_FORMAT_OSD_STRING, &res);
if (e >= 0)
add_af_mpv_alloc(af, res);
if (!pushed_error(J, e, 2))
js_pushstring(J, res);
}
// args: id, name, type
static void script__observe_property(js_State *J)
{
const char *fmts[] = {"none", "native", "bool", "string", "number", NULL};
const mpv_format mf[] = {MPV_FORMAT_NONE, MPV_FORMAT_NODE, MPV_FORMAT_FLAG,
MPV_FORMAT_STRING, MPV_FORMAT_DOUBLE};
mpv_format f = mf[checkopt(J, 3, "none", fmts, "observe type")];
int e = mpv_observe_property(jclient(J), jsL_checkuint64(J, 1),
js_tostring(J, 2),
f);
push_status(J, e);
}
// args: id
static void script__unobserve_property(js_State *J)
{
int e = mpv_unobserve_property(jclient(J), jsL_checkuint64(J, 1));
push_status(J, e);
}
// args: native (array of command and args, similar to commandv) [,def]
static void script_command_native(js_State *J, void *af)
{
mpv_node cmd;
makenode(af, &cmd, J, 1);
mpv_node *presult_node = new_af_mpv_node(af);
int e = mpv_command_node(jclient(J), &cmd, presult_node);
if (!pushed_error(J, e, 2))
pushnode(J, presult_node);
}
// args: async-command-id, native-command
static void script__command_native_async(js_State *J, void *af)
{
uint64_t id = jsL_checkuint64(J, 1);
struct mpv_node node;
makenode(af, &node, J, 2);
push_status(J, mpv_command_node_async(jclient(J), id, &node));
}
// args: async-command-id
static void script__abort_async_command(js_State *J)
{
mpv_abort_async_command(jclient(J), jsL_checkuint64(J, 1));
push_success(J);
}
// args: none, result in millisec
static void script_get_time_ms(js_State *J)
{
js_pushnumber(J, mpv_get_time_us(jclient(J)) / (double)(1000));
}
// push object with properties names (NULL terminated) with respective vals
static void push_nums_obj(js_State *J, const char * const names[],
const double vals[])
{
js_newobject(J);
for (int i = 0; names[i]; i++) {
js_pushnumber(J, vals[i]);
js_setproperty(J, -2, names[i]);
}
}
// args: input-section-name, x0, y0, x1, y1
static void script_input_set_section_mouse_area(js_State *J)
{
char *section = (char *)js_tostring(J, 1);
mp_input_set_section_mouse_area(jctx(J)->mpctx->input, section,
jsL_checkint(J, 2), jsL_checkint(J, 3), // x0, y0
jsL_checkint(J, 4), jsL_checkint(J, 5)); // x1, y1
push_success(J);
}
// args: time-in-ms [,format-string]
static void script_format_time(js_State *J, void *af)
{
double t = js_tonumber(J, 1);
const char *fmt = js_isundefined(J, 2) ? "%H:%M:%S" : js_tostring(J, 2);
char *r = talloc_steal(af, mp_format_time_fmt(fmt, t));
if (!r)
js_error(J, "Invalid time format string '%s'", fmt);
js_pushstring(J, r);
}
// TODO: untested
static void script_get_wakeup_pipe(js_State *J)
{
js_pushnumber(J, mpv_get_wakeup_pipe(jclient(J)));
}
// args: name (str), priority (int), id (uint)
static void script__hook_add(js_State *J)
{
const char *name = js_tostring(J, 1);
int pri = jsL_checkint(J, 2);
uint64_t id = jsL_checkuint64(J, 3);
push_status(J, mpv_hook_add(jclient(J), id, name, pri));
}
// args: id (uint)
static void script__hook_continue(js_State *J)
{
push_status(J, mpv_hook_continue(jclient(J), jsL_checkuint64(J, 1)));
}
/**********************************************************************
* mp.utils
*********************************************************************/
// args: [path [,filter]]
static void script_readdir(js_State *J, void *af)
{
// 0 1 2 3
const char *filters[] = {"all", "files", "dirs", "normal", NULL};
const char *path = js_isundefined(J, 1) ? "." : js_tostring(J, 1);
int t = checkopt(J, 2, "normal", filters, "listing filter");
DIR *dir = opendir(path);
if (!dir) {
push_failure(J, "Cannot open dir");
return;
}
add_af_dir(af, dir);
set_last_error(jctx(J), 0, NULL);
js_newarray(J); // the return value
char *fullpath = talloc_strdup(af, "");
struct dirent *e;
int n = 0;
while ((e = readdir(dir))) {
char *name = e->d_name;
if (t) {
if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
continue;
if (fullpath)
fullpath[0] = '\0';
fullpath = talloc_asprintf_append(fullpath, "%s/%s", path, name);
struct stat st;
if (stat(fullpath, &st))
continue;
if (!(((t & 1) && S_ISREG(st.st_mode)) ||
((t & 2) && S_ISDIR(st.st_mode))))
{
continue;
}
}
js_pushstring(J, name);
js_setindex(J, -2, n++);
}
}
static void script_file_info(js_State *J)
{
const char *path = js_tostring(J, 1);
struct stat statbuf;
if (stat(path, &statbuf) != 0) {
push_failure(J, "Cannot stat path");
return;
}
// Clear last error
set_last_error(jctx(J), 0, NULL);
const char * stat_names[] = {
"mode", "size",
"atime", "mtime", "ctime", NULL
};
const double stat_values[] = {
statbuf.st_mode,
statbuf.st_size,
statbuf.st_atime,
statbuf.st_mtime,
statbuf.st_ctime
};
// Create an object and add all fields
push_nums_obj(J, stat_names, stat_values);
// Convenience booleans
js_pushboolean(J, S_ISREG(statbuf.st_mode));
js_setproperty(J, -2, "is_file");
js_pushboolean(J, S_ISDIR(statbuf.st_mode));
js_setproperty(J, -2, "is_dir");
}
static void script_split_path(js_State *J)
{
const char *p = js_tostring(J, 1);
bstr fname = mp_dirname(p);
js_newarray(J);
js_pushlstring(J, fname.start, fname.len);
js_setindex(J, -2, 0);
js_pushstring(J, mp_basename(p));
js_setindex(J, -2, 1);
}
static void script_join_path(js_State *J, void *af)
{
js_pushstring(J, mp_path_join(af, js_tostring(J, 1), js_tostring(J, 2)));
}
// args: is_append, prefixed file name, data (c-str)
static void script__write_file(js_State *J, void *af)
{
static const char *prefix = "file://";
bool append = js_toboolean(J, 1);
const char *fname = js_tostring(J, 2);
const char *data = js_tostring(J, 3);
const char *opstr = append ? "append" : "write";
if (strstr(fname, prefix) != fname) // simple protection for incorrect use
js_error(J, "File name must be prefixed with '%s'", prefix);
fname += strlen(prefix);
fname = mp_get_user_path(af, jctx(J)->mpctx->global, fname);
MP_VERBOSE(jctx(J), "%s file '%s'\n", opstr, fname);
FILE *f = fopen(fname, append ? "ab" : "wb");
if (!f)
js_error(J, "Cannot open (%s) file: '%s'", opstr, fname);
add_af_file(af, f);
int len = strlen(data); // limited by terminating null
int wrote = fwrite(data, 1, len, f);
if (len != wrote)
js_error(J, "Cannot %s to file: '%s'", opstr, fname);
js_pushboolean(J, 1); // success. doesn't touch last_error
}
// args: env var name
static void script_getenv(js_State *J)
{
const char *v = getenv(js_tostring(J, 1));
if (v) {
js_pushstring(J, v);
} else {
js_pushundefined(J);
}
}
// args: none
static void script_get_env_list(js_State *J)
{
js_newarray(J);
for (int n = 0; environ && environ[n]; n++) {
js_pushstring(J, environ[n]);
js_setindex(J, -2, n);
}
}
// args: as-filename, content-string, returns the compiled result as a function
static void script_compile_js(js_State *J)
{
js_loadstring(J, js_tostring(J, 1), js_tostring(J, 2));
}
// args: true = print info (with the warning report function - no info report)
static void script__gc(js_State *J)
{
js_gc(J, js_toboolean(J, 1) ? 1 : 0);
push_success(J);
}
/**********************************************************************
* Core functions: pushnode, makenode and the event loop backend
*********************************************************************/
// pushes a js value/array/object from an mpv_node
static void pushnode(js_State *J, mpv_node *node)
{
int len;
switch (node->format) {
case MPV_FORMAT_NONE: js_pushnull(J); break;
case MPV_FORMAT_STRING: js_pushstring(J, node->u.string); break;
case MPV_FORMAT_INT64: js_pushnumber(J, node->u.int64); break;
case MPV_FORMAT_DOUBLE: js_pushnumber(J, node->u.double_); break;
case MPV_FORMAT_FLAG: js_pushboolean(J, node->u.flag); break;
case MPV_FORMAT_BYTE_ARRAY:
js_pushlstring(J, node->u.ba->data, node->u.ba->size);
break;
case MPV_FORMAT_NODE_ARRAY:
js_newarray(J);
len = node->u.list->num;
for (int n = 0; n < len; n++) {
pushnode(J, &node->u.list->values[n]);
js_setindex(J, -2, n);
}
break;
case MPV_FORMAT_NODE_MAP:
js_newobject(J);
len = node->u.list->num;
for (int n = 0; n < len; n++) {
pushnode(J, &node->u.list->values[n]);
js_setproperty(J, -2, node->u.list->keys[n]);
}
break;
default:
js_pushstring(J, "[UNSUPPORTED_MPV_FORMAT]");
break;
}
}
// For the object at stack index idx, extract the (own) property names into
// keys array (and allocate it to accommodate) and return the number of keys.
static int get_obj_properties(void *ta_ctx, char ***keys, js_State *J, int idx)
{
int length = 0;
js_pushiterator(J, idx, 1);
*keys = talloc_new(ta_ctx);
const char *name;
while ((name = js_nextiterator(J, -1)))
MP_TARRAY_APPEND(ta_ctx, *keys, length, talloc_strdup(ta_ctx, name));
js_pop(J, 1); // the iterator
return length;
}
// true if we don't lose (too much) precision when casting to int64
static bool same_as_int64(double d)
{
// The range checks also validly filter inf and nan, so behavior is defined
return d >= INT64_MIN && d <= (double) INT64_MAX && d == (int64_t)d;
}
static int jsL_checkint(js_State *J, int idx)
{
double d = js_tonumber(J, idx);
if (!(d >= INT_MIN && d <= INT_MAX))
js_error(J, "int out of range at index %d", idx);
return d;
}
static uint64_t jsL_checkuint64(js_State *J, int idx)
{
double d = js_tonumber(J, idx);
if (!(d >= 0 && d <= (double) UINT64_MAX))
js_error(J, "uint64 out of range at index %d", idx);
return d;
}
// From the js stack value/array/object at index idx
static void makenode(void *ta_ctx, mpv_node *dst, js_State *J, int idx)
{
if (js_isundefined(J, idx) || js_isnull(J, idx)) {
dst->format = MPV_FORMAT_NONE;
} else if (js_isboolean(J, idx)) {
dst->format = MPV_FORMAT_FLAG;
dst->u.flag = js_toboolean(J, idx);
} else if (js_isnumber(J, idx)) {
double val = js_tonumber(J, idx);
if (same_as_int64(val)) { // use int, because we can
dst->format = MPV_FORMAT_INT64;
dst->u.int64 = val;
} else {
dst->format = MPV_FORMAT_DOUBLE;
dst->u.double_ = val;
}
} else if (js_isarray(J, idx)) {
dst->format = MPV_FORMAT_NODE_ARRAY;
dst->u.list = talloc(ta_ctx, struct mpv_node_list);
dst->u.list->keys = NULL;
int length = js_getlength(J, idx);
dst->u.list->num = length;
dst->u.list->values = talloc_array(ta_ctx, mpv_node, length);
for (int n = 0; n < length; n++) {
js_getindex(J, idx, n);
makenode(ta_ctx, &dst->u.list->values[n], J, -1);
js_pop(J, 1);
}
} else if (js_isobject(J, idx)) {
dst->format = MPV_FORMAT_NODE_MAP;
dst->u.list = talloc(ta_ctx, struct mpv_node_list);
int length = get_obj_properties(ta_ctx, &dst->u.list->keys, J, idx);
dst->u.list->num = length;
dst->u.list->values = talloc_array(ta_ctx, mpv_node, length);
for (int n = 0; n < length; n++) {
js_getproperty(J, idx, dst->u.list->keys[n]);
makenode(ta_ctx, &dst->u.list->values[n], J, -1);
js_pop(J, 1);
}
} else { // string, or anything else as string
dst->format = MPV_FORMAT_STRING;
dst->u.string = talloc_strdup(ta_ctx, js_tostring(J, idx));
}
}
// args: wait in secs (infinite if negative) if mpv doesn't send events earlier.
static void script_wait_event(js_State *J, void *af)
{
double timeout = js_isnumber(J, 1) ? js_tonumber(J, 1) : -1;
mpv_event *event = mpv_wait_event(jclient(J), timeout);
mpv_node *rn = new_af_mpv_node(af);
mpv_event_to_node(rn, event);
pushnode(J, rn);
}
/**********************************************************************
* Script functions setup
*********************************************************************/
#define FN_ENTRY(name, length) {#name, length, script_ ## name, NULL}
#define AF_ENTRY(name, length) {#name, length, NULL, script_ ## name}
struct fn_entry {
const char *name;
int length;
js_CFunction jsc_fn;
af_CFunction afc_fn;
};
// Names starting with underscore are wrapped at @defaults.js
// FN_ENTRY is a normal js C function, AF_ENTRY is an autofree js C function.
static const struct fn_entry main_fns[] = {
FN_ENTRY(log, 1),
AF_ENTRY(wait_event, 1),
FN_ENTRY(_request_event, 2),
AF_ENTRY(find_config_file, 1),
FN_ENTRY(command, 1),
FN_ENTRY(commandv, 0),
AF_ENTRY(command_native, 2),
AF_ENTRY(_command_native_async, 2),
FN_ENTRY(_abort_async_command, 1),
FN_ENTRY(del_property, 1),
FN_ENTRY(get_property_bool, 2),
FN_ENTRY(get_property_number, 2),
AF_ENTRY(get_property_native, 2),
AF_ENTRY(get_property, 2),
AF_ENTRY(get_property_osd, 2),
FN_ENTRY(set_property, 2),
FN_ENTRY(set_property_bool, 2),
FN_ENTRY(set_property_number, 2),
AF_ENTRY(set_property_native, 2),
FN_ENTRY(_observe_property, 3),
FN_ENTRY(_unobserve_property, 1),
FN_ENTRY(get_time_ms, 0),
AF_ENTRY(format_time, 2),
FN_ENTRY(enable_messages, 1),
FN_ENTRY(get_wakeup_pipe, 0),
FN_ENTRY(_hook_add, 3),
FN_ENTRY(_hook_continue, 1),
FN_ENTRY(input_set_section_mouse_area, 5),
FN_ENTRY(last_error, 0),
FN_ENTRY(_set_last_error, 1),
{0}
};
static const struct fn_entry utils_fns[] = {
AF_ENTRY(readdir, 2),
FN_ENTRY(file_info, 1),
FN_ENTRY(split_path, 1),
AF_ENTRY(join_path, 2),
FN_ENTRY(get_env_list, 0),
FN_ENTRY(read_file, 2),
AF_ENTRY(_write_file, 3),
FN_ENTRY(getenv, 1),
FN_ENTRY(compile_js, 2),
FN_ENTRY(_gc, 1),
{0}
};
// Adds an object <module> with the functions at e to the top object
static void add_package_fns(js_State *J, const char *module,
const struct fn_entry *e)
{
js_newobject(J);
for (int n = 0; e[n].name; n++) {
if (e[n].jsc_fn) {
js_newcfunction(J, e[n].jsc_fn, e[n].name, e[n].length);
} else {
af_newcfunction(J, e[n].afc_fn, e[n].name, e[n].length);
}
js_setproperty(J, -2, e[n].name);
}
js_setproperty(J, -2, module);
}
// Called directly, adds functions/vars to the caller's this.
static void add_functions(js_State *J, struct script_ctx *ctx)
{
js_copy(J, 0);
add_package_fns(J, "mp", main_fns);
js_getproperty(J, 0, "mp"); // + this mp
add_package_fns(J, "utils", utils_fns);
js_pushstring(J, mpv_client_name(ctx->client));
js_setproperty(J, -2, "script_name");
js_pushstring(J, ctx->filename);
js_setproperty(J, -2, "script_file");
if (ctx->path) {
js_pushstring(J, ctx->path);
js_setproperty(J, -2, "script_path");
}
js_pop(J, 2); // leave the stack as we got it
}
// main export of this file, used by cplayer to load js scripts
const struct mp_scripting mp_scripting_js = {
.name = "js",
.file_ext = "js",
.load = s_load_javascript,
};