|
| 1 | +<?php |
| 2 | + |
| 3 | +/* |
| 4 | + * This file is part of the Symfony package. |
| 5 | + * |
| 6 | + * (c) Fabien Potencier <fabien@symfony.com> |
| 7 | + * |
| 8 | + * For the full copyright and license information, please view the LICENSE |
| 9 | + * file that was distributed with this source code. |
| 10 | + */ |
| 11 | + |
| 12 | +namespace Symfony\Component\VarDumper\Caster; |
| 13 | + |
| 14 | +use FFI\CData; |
| 15 | +use FFI\CType; |
| 16 | +use Symfony\Component\VarDumper\Cloner\Stub; |
| 17 | + |
| 18 | +/** |
| 19 | + * Casts FFI extension classes to array representation. |
| 20 | + * |
| 21 | + * @author Nesmeyanov Kirill <nesk@xakep.ru> |
| 22 | + */ |
| 23 | +final class FFICaster |
| 24 | +{ |
| 25 | + /** |
| 26 | + * In case of "char*" contains a string, the length of which depends on |
| 27 | + * some other parameter, then during the generation of the string it is |
| 28 | + * possible to go beyond the allowable memory area. |
| 29 | + * |
| 30 | + * This restriction serves to ensure that processing does not take |
| 31 | + * up the entire allowable PHP memory limit. |
| 32 | + */ |
| 33 | + private const MAX_STRING_LENGTH = 255; |
| 34 | + |
| 35 | + public static function castCTypeOrCData(CData|CType $data, array $args, Stub $stub): array |
| 36 | + { |
| 37 | + if ($data instanceof CType) { |
| 38 | + $type = $data; |
| 39 | + $data = null; |
| 40 | + } else { |
| 41 | + $type = \FFI::typeof($data); |
| 42 | + } |
| 43 | + |
| 44 | + $stub->class = sprintf('%s<%s> size %d align %d', ($data ?? $type)::class, $type->getName(), $type->getSize(), $type->getAlignment()); |
| 45 | + |
| 46 | + return match ($type->getKind()) { |
| 47 | + CType::TYPE_FLOAT, |
| 48 | + CType::TYPE_DOUBLE, |
| 49 | + \defined('\FFI\CType::TYPE_LONGDOUBLE') ? CType::TYPE_LONGDOUBLE : -1, |
| 50 | + CType::TYPE_UINT8, |
| 51 | + CType::TYPE_SINT8, |
| 52 | + CType::TYPE_UINT16, |
| 53 | + CType::TYPE_SINT16, |
| 54 | + CType::TYPE_UINT32, |
| 55 | + CType::TYPE_SINT32, |
| 56 | + CType::TYPE_UINT64, |
| 57 | + CType::TYPE_SINT64, |
| 58 | + CType::TYPE_BOOL, |
| 59 | + CType::TYPE_CHAR, |
| 60 | + CType::TYPE_ENUM => null !== $data ? [Caster::PREFIX_VIRTUAL.'cdata' => $data->cdata] : [], |
| 61 | + CType::TYPE_POINTER => self::castFFIPointer($stub, $type, $data), |
| 62 | + CType::TYPE_STRUCT => self::castFFIStructLike($type, $data), |
| 63 | + CType::TYPE_FUNC => self::castFFIFunction($stub, $type), |
| 64 | + default => $args, |
| 65 | + }; |
| 66 | + } |
| 67 | + |
| 68 | + private static function castFFIFunction(Stub $stub, CType $type): array |
| 69 | + { |
| 70 | + $arguments = []; |
| 71 | + |
| 72 | + for ($i = 0, $count = $type->getFuncParameterCount(); $i < $count; ++$i) { |
| 73 | + $param = $type->getFuncParameterType($i); |
| 74 | + |
| 75 | + $arguments[] = $param->getName(); |
| 76 | + } |
| 77 | + |
| 78 | + $abi = match ($type->getFuncABI()) { |
| 79 | + CType::ABI_DEFAULT, |
| 80 | + CType::ABI_CDECL => '[cdecl]', |
| 81 | + CType::ABI_FASTCALL => '[fastcall]', |
| 82 | + CType::ABI_THISCALL => '[thiscall]', |
| 83 | + CType::ABI_STDCALL => '[stdcall]', |
| 84 | + CType::ABI_PASCAL => '[pascal]', |
| 85 | + CType::ABI_REGISTER => '[register]', |
| 86 | + CType::ABI_MS => '[ms]', |
| 87 | + CType::ABI_SYSV => '[sysv]', |
| 88 | + CType::ABI_VECTORCALL => '[vectorcall]', |
| 89 | + default => '[unknown abi]' |
| 90 | + }; |
| 91 | + |
| 92 | + $returnType = $type->getFuncReturnType(); |
| 93 | + |
| 94 | + $stub->class = $abi.' callable('.implode(', ', $arguments).'): ' |
| 95 | + .$returnType->getName(); |
| 96 | + |
| 97 | + return [Caster::PREFIX_VIRTUAL.'returnType' => $returnType]; |
| 98 | + } |
| 99 | + |
| 100 | + private static function castFFIPointer(Stub $stub, CType $type, CData $data = null): array |
| 101 | + { |
| 102 | + $ptr = $type->getPointerType(); |
| 103 | + |
| 104 | + if (null === $data) { |
| 105 | + return [Caster::PREFIX_VIRTUAL.'0' => $ptr]; |
| 106 | + } |
| 107 | + |
| 108 | + return match ($ptr->getKind()) { |
| 109 | + CType::TYPE_CHAR => [Caster::PREFIX_VIRTUAL.'cdata' => self::castFFIStringValue($data)], |
| 110 | + CType::TYPE_FUNC => self::castFFIFunction($stub, $ptr), |
| 111 | + default => [Caster::PREFIX_VIRTUAL.'cdata' => $data[0]], |
| 112 | + }; |
| 113 | + } |
| 114 | + |
| 115 | + private static function castFFIStringValue(CData $data): string|CutStub |
| 116 | + { |
| 117 | + $result = []; |
| 118 | + |
| 119 | + for ($i = 0; $i < self::MAX_STRING_LENGTH; ++$i) { |
| 120 | + $result[$i] = $data[$i]; |
| 121 | + |
| 122 | + if ("\0" === $result[$i]) { |
| 123 | + return implode('', $result); |
| 124 | + } |
| 125 | + } |
| 126 | + |
| 127 | + $string = implode('', $result); |
| 128 | + $stub = new CutStub($string); |
| 129 | + $stub->cut = -1; |
| 130 | + $stub->value = $string; |
| 131 | + |
| 132 | + return $stub; |
| 133 | + } |
| 134 | + |
| 135 | + private static function castFFIStructLike(CType $type, CData $data = null): array |
| 136 | + { |
| 137 | + $isUnion = ($type->getAttributes() & CType::ATTR_UNION) === CType::ATTR_UNION; |
| 138 | + |
| 139 | + $result = []; |
| 140 | + |
| 141 | + foreach ($type->getStructFieldNames() as $name) { |
| 142 | + $field = $type->getStructFieldType($name); |
| 143 | + |
| 144 | + // Retrieving the value of a field from a union containing |
| 145 | + // a pointer is not a safe operation, because may contain |
| 146 | + // incorrect data. |
| 147 | + $isUnsafe = $isUnion && CType::TYPE_POINTER === $field->getKind(); |
| 148 | + |
| 149 | + if ($isUnsafe) { |
| 150 | + $result[Caster::PREFIX_VIRTUAL.$name.'?'] = $field; |
| 151 | + } elseif (null === $data) { |
| 152 | + $result[Caster::PREFIX_VIRTUAL.$name] = $field; |
| 153 | + } else { |
| 154 | + $fieldName = $data->{$name} instanceof CData ? '' : $field->getName().' '; |
| 155 | + $result[Caster::PREFIX_VIRTUAL.$fieldName.$name] = $data->{$name}; |
| 156 | + } |
| 157 | + } |
| 158 | + |
| 159 | + return $result; |
| 160 | + } |
| 161 | +} |
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