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ext/standard/stream: Use FCC instead of zval for notification callback #19024

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Merged
merged 2 commits into from
Jul 6, 2025
+76 −26
Merged

ext/standard/stream: Use FCC instead of zval for notification callback #19024

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8a18018
ext/standard/stream: Use FCC instead of zval for notification callback
Girgias Jul 3, 2025
f90cf29
Fix
Girgias Jul 5, 2025
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40 changes: 24 additions & 16 deletions ext/standard/streamsfuncs.c
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Original file line number Diff line number Diff line change
Expand Up @@ -856,10 +856,7 @@ PHP_FUNCTION(stream_select)
static void user_space_stream_notifier(php_stream_context *context, int notifycode, int severity,
char *xmsg, int xcode, size_t bytes_sofar, size_t bytes_max, void * ptr)
{
zval *callback = &context->notifier->ptr;
zval retval;
zval zvs[6];
int i;

ZVAL_LONG(&zvs[0], notifycode);
ZVAL_LONG(&zvs[1], severity);
Expand All @@ -872,21 +869,20 @@ static void user_space_stream_notifier(php_stream_context *context, int notifyco
ZVAL_LONG(&zvs[4], bytes_sofar);
ZVAL_LONG(&zvs[5], bytes_max);

if (FAILURE == call_user_function(NULL, NULL, callback, &retval, 6, zvs)) {
php_error_docref(NULL, E_WARNING, "Failed to call user notifier");
}
for (i = 0; i < 6; i++) {
zend_call_known_fcc(context->notifier->fcc, NULL, 6, zvs, NULL);
for (uint8_t i = 0; i < 6; i++) {
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Fun fact: If not unrolled, using an (unsigned) int would be better in the sense that the generated assembly for both x86-64 and arm64 is shorter. For x86 it saves an instruction prefix byte to switch to 8 bit mode, and for arm64 it saves an instruction.
However, the loop is likely unrolled in which case it doesn't matter, but just something to take into account that using a shorter type is not always better.

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Actually, why do we even have a loop? Just call the zval_ptr_dtor(_str) on &zvs[2] ?

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I was thinking about that, but can't this be an issue if the notifier callback takes the arguments by-ref and changes them to strings?

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No, because the conversion happens on the call frame, not on the original zvals.

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ACK, will change then

zval_ptr_dtor(&zvs[i]);
}
zval_ptr_dtor(&retval);
}

static void user_space_stream_notifier_dtor(php_stream_notifier *notifier)
{
if (notifier && Z_TYPE(notifier->ptr) != IS_UNDEF) {
zval_ptr_dtor(&notifier->ptr);
ZVAL_UNDEF(&notifier->ptr);
}
ZEND_ASSERT(notifier);
ZEND_ASSERT(notifier->fcc);
ZEND_ASSERT(notifier->fcc->function_handler);
zend_fcc_dtor(notifier->fcc);
efree(notifier->fcc);
notifier->fcc = NULL;
}

static zend_result parse_context_options(php_stream_context *context, HashTable *options)
Expand Down Expand Up @@ -924,9 +920,19 @@ static zend_result parse_context_params(php_stream_context *context, HashTable *
context->notifier = NULL;
}

zend_fcall_info_cache *fcc = emalloc(sizeof(*fcc));
char *error;
if (!zend_is_callable_ex(tmp, NULL, 0, NULL, fcc, &error)) {
zend_argument_type_error(1, "must be an array with valid callbacks as values, %s", error);
efree(fcc);
efree(error);
return FAILURE;
}
zend_fcc_addref(fcc);

context->notifier = php_stream_notification_alloc();
context->notifier->func = user_space_stream_notifier;
ZVAL_COPY(&context->notifier->ptr, tmp);
context->notifier->fcc = fcc;
context->notifier->dtor = user_space_stream_notifier_dtor;
}
if (NULL != (tmp = zend_hash_str_find(params, "options", sizeof("options")-1))) {
Expand Down Expand Up @@ -1123,9 +1129,11 @@ PHP_FUNCTION(stream_context_get_params)
}

array_init(return_value);
if (context->notifier && Z_TYPE(context->notifier->ptr) != IS_UNDEF && context->notifier->func == user_space_stream_notifier) {
Z_TRY_ADDREF(context->notifier->ptr);
add_assoc_zval_ex(return_value, "notification", sizeof("notification")-1, &context->notifier->ptr);
if (context->notifier && context->notifier->fcc) {
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How can you have a notifier without a valid fcc field?

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That I don't know as I'm not super familiar with the code, so I went the safe route of checking it exists.

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How can you have a notifier without a valid fcc field?

Extensions. In fact this change is an actual breaking change. The .ptr could be used to store store arbitrary metadata for the extension-specific .func. Now it can no longer store arbitrary metadata. It should be a void * instead (that is then cast to zend_fcall_info_cache * for user_space_stream_notifier).

There was a reason the if() previously checked for ->func == user_space_stream_notifier instead of asserting that this is the case. Otherwise we would not need func in the first place and could just hardcode it to user_space_stream_notifier.

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Fix is in #19158.

ZEND_ASSERT(context->notifier->func == user_space_stream_notifier);
zval fn;
zend_get_callable_zval_from_fcc(context->notifier->fcc, &fn);
add_assoc_zval_ex(return_value, ZEND_STRL("notification"), &fn);
}
Z_TRY_ADDREF(context->options);
add_assoc_zval_ex(return_value, "options", sizeof("options")-1, &context->options);
Expand Down
16 changes: 9 additions & 7 deletions ext/standard/tests/streams/stream_context_get_params_001.phpt
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Original file line number Diff line number Diff line change
Expand Up @@ -4,16 +4,19 @@ stream_context_get_params()
<?php

$ctx = stream_context_create();
var_dump($ctx);
var_dump(stream_context_get_params($ctx));

var_dump(stream_context_set_option($ctx, "foo","bar","baz"));
var_dump(stream_context_get_params($ctx));

function stream_notification_callback() {}
var_dump(stream_context_set_params($ctx, array("notification" => "stream_notification_callback")));
var_dump(stream_context_get_params($ctx));

var_dump(stream_context_set_params($ctx, array("notification" => array("stream","notification_callback"))));
class MyStream {
public static function notification_callback() {}
}
var_dump(stream_context_set_params($ctx, array("notification" => ["MyStream", "notification_callback"])));
var_dump(stream_context_get_params($ctx));

var_dump(stream_context_get_params($ctx));
Expand All @@ -22,8 +25,7 @@ var_dump(stream_context_get_params($ctx));
var_dump(stream_context_get_options($ctx));

?>
--EXPECTF--
resource(%d) of type (stream-context)
--EXPECT--
array(1) {
["options"]=>
array(0) {
Expand Down Expand Up @@ -58,7 +60,7 @@ array(2) {
["notification"]=>
array(2) {
[0]=>
string(6) "stream"
string(8) "MyStream"
[1]=>
string(21) "notification_callback"
}
Expand All @@ -75,7 +77,7 @@ array(2) {
["notification"]=>
array(2) {
[0]=>
string(6) "stream"
string(8) "MyStream"
[1]=>
string(21) "notification_callback"
}
Expand All @@ -99,7 +101,7 @@ array(2) {
["notification"]=>
array(2) {
[0]=>
string(6) "stream"
string(8) "MyStream"
[1]=>
string(21) "notification_callback"
}
Expand Down
21 changes: 21 additions & 0 deletions ext/standard/tests/streams/stream_context_set_params_notification_error.phpt
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@@ -0,0 +1,21 @@
--TEST--
stream_context_set_params() with invalid notification option
--FILE--
<?php

$ctx = stream_context_create();
try {
var_dump(stream_context_set_params($ctx, ["notification" => "fn_not_exist"]));
} catch (\Throwable $e) {
echo $e::class, ': ', $e->getMessage(), PHP_EOL;
}
try {
var_dump(stream_context_set_params($ctx, ["notification" => ["myclass", "fn_not_exist"]]));
} catch (\Throwable $e) {
echo $e::class, ': ', $e->getMessage(), PHP_EOL;
}

?>
--EXPECT--
TypeError: stream_context_set_params(): Argument #1 ($context) must be an array with valid callbacks as values, function "fn_not_exist" not found or invalid function name
TypeError: stream_context_set_params(): Argument #1 ($context) must be an array with valid callbacks as values, class "myclass" not found
20 changes: 20 additions & 0 deletions ext/standard/tests/streams/stream_context_set_params_notification_valid_then_invalid.phpt
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@@ -0,0 +1,20 @@
--TEST--
stream_context_set_params() with valid, then invalid notification option
--FILE--
<?php

function foo() {}

$ctx = stream_context_create();
var_dump(stream_context_set_params($ctx, ["notification" => "foo"]));

try {
var_dump(stream_context_set_params($ctx, ["notification" => "fn_not_exist"]));
} catch (\Throwable $e) {
echo $e::class, ': ', $e->getMessage(), PHP_EOL;
}

?>
--EXPECT--
bool(true)
TypeError: stream_context_set_params(): Argument #1 ($context) must be an array with valid callbacks as values, function "fn_not_exist" not found or invalid function name
2 changes: 1 addition & 1 deletion main/streams/php_stream_context.h
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Expand Up @@ -44,7 +44,7 @@ typedef struct _php_stream_notifier php_stream_notifier;
struct _php_stream_notifier {
php_stream_notification_func func;
void (*dtor)(php_stream_notifier *notifier);
zval ptr;
zend_fcall_info_cache *fcc;
int mask;
size_t progress, progress_max; /* position for progress notification */
};
Expand Down