Deprecated: Creation of dynamic property wpdb::$categories is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/wp-db.php on line 668

Deprecated: Creation of dynamic property wpdb::$post2cat is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/wp-db.php on line 668

Deprecated: Creation of dynamic property wpdb::$link2cat is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/wp-db.php on line 668

Deprecated: Return type of WP_Theme::offsetExists($offset) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-theme.php on line 554

Deprecated: Return type of WP_Theme::offsetGet($offset) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-theme.php on line 595

Deprecated: Return type of WP_Theme::offsetSet($offset, $value) should either be compatible with ArrayAccess::offsetSet(mixed $offset, mixed $value): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-theme.php on line 535

Deprecated: Return type of WP_Theme::offsetUnset($offset) should either be compatible with ArrayAccess::offsetUnset(mixed $offset): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-theme.php on line 544

Deprecated: Using ${var} in strings is deprecated, use {$var} instead in /usr/home/bugyo/public_html/b-log/wp-includes/comment-template.php on line 1739

Deprecated: Return type of WP_REST_Request::offsetExists($offset) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/rest-api/class-wp-rest-request.php on line 960

Deprecated: Return type of WP_REST_Request::offsetGet($offset) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/rest-api/class-wp-rest-request.php on line 980

Deprecated: Return type of WP_REST_Request::offsetSet($offset, $value) should either be compatible with ArrayAccess::offsetSet(mixed $offset, mixed $value): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/rest-api/class-wp-rest-request.php on line 992

Deprecated: Return type of WP_REST_Request::offsetUnset($offset) should either be compatible with ArrayAccess::offsetUnset(mixed $offset): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/rest-api/class-wp-rest-request.php on line 1003

Deprecated: Return type of WP_Block_List::current() should either be compatible with Iterator::current(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 151

Deprecated: Return type of WP_Block_List::next() should either be compatible with Iterator::next(): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 175

Deprecated: Return type of WP_Block_List::key() should either be compatible with Iterator::key(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 164

Deprecated: Return type of WP_Block_List::valid() should either be compatible with Iterator::valid(): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 186

Deprecated: Return type of WP_Block_List::rewind() should either be compatible with Iterator::rewind(): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 138

Deprecated: Return type of WP_Block_List::offsetExists($index) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 75

Deprecated: Return type of WP_Block_List::offsetGet($index) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 89

Deprecated: Return type of WP_Block_List::offsetSet($index, $value) should either be compatible with ArrayAccess::offsetSet(mixed $offset, mixed $value): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 110

Deprecated: Return type of WP_Block_List::offsetUnset($index) should either be compatible with ArrayAccess::offsetUnset(mixed $offset): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 127

Deprecated: Return type of WP_Block_List::count() should either be compatible with Countable::count(): int, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-block-list.php on line 199

Deprecated: Creation of dynamic property WP_Term::$object_id is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-term.php on line 198

Deprecated: Creation of dynamic property WP_Term::$object_id is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-term.php on line 198

Deprecated: Creation of dynamic property WP_Term::$object_id is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-term.php on line 198

Deprecated: Creation of dynamic property WP_Term::$object_id is deprecated in /usr/home/bugyo/public_html/b-log/wp-includes/class-wp-term.php on line 198
LD_PRELOAD – B-LOG
B-LOG

LD_PRELOAD

MovableTypeのデータベースをBerkeley DBからSQLiteに変更しようとして、変換スクリプトを実行すると、
ELFのローダが、

/libexec/ld-elf.so.1: /usr/local/lib/libsqlite3.so.8:
Undefined symbol "pthread_create"

というエラーを吐いて先に進めない。

実行プログラムの形式にELFを採用しているOSではLD_PRELOADという環境変数を設定しておくと、
指定したライブラリを他のライブラリより先にロードしておくことができるらしい。
これを使って任意の関数を上書きしたりできるそう。

>setenv LD_PRELOAD /usr/lib/libpthread.so.2
>./mt-db2sql.cgi

とすると問題なく実行できた。

MovableTypeで使うデータベースをSQLiteに設定してブラウザからアクセスしてみると、
Internal Server Errorが。
エラーログをみると例のエラー、当然か。
CGI実行時にApacheから環境変数を設定できればいいんだろうなと思って調べてみると、
mod_envというのがあるらしい。Apacheを入れたときにデフォルトでロードするようになっていた。
httpd.confに

SetEnv LD_PRELOAD /usr/lib/libpthread.so.2

のようにSetEnvディレクトリを書く。
ブラウザからアクセスすると問題なく動いた。

LD_PRELOADを使って任意の関数呼び出しにフックしてみる
CGIの裏側見せます