[experiment] add alternative wasm sqlite3 implementation available via build-tag (#2863)

This allows for building GoToSocial with [SQLite transpiled to WASM](https://github.com/ncruces/go-sqlite3) and accessed through [Wazero](https://wazero.io/).

1 files changed, 292 insertions, 0 deletions

diff --git a/vendor/github.com/tetratelabs/wazero/experimental/sys/fs.go b/vendor/github.com/tetratelabs/wazero/experimental/sys/fs.go
new file mode 100644
index 000000000..87810510a
--- /dev/null
+++ b/vendor/github.com/tetratelabs/wazero/experimental/sys/fs.go
@@ -0,0 +1,292 @@
+package sys
+
+import (
+	"io/fs"
+
+	"github.com/tetratelabs/wazero/sys"
+)
+
+// FS is a writeable fs.FS bridge backed by syscall functions needed for ABI
+// including WASI.
+//
+// Implementations should embed UnimplementedFS for forward compatibility. Any
+// unsupported method or parameter should return ENO
+//
+// # Errors
+//
+// All methods that can return an error return a Errno, which is zero
+// on success.
+//
+// Restricting to Errno matches current WebAssembly host functions,
+// which are constrained to well-known error codes. For example, WASI maps syscall
+// errors to u32 numeric values.
+//
+// # Notes
+//
+// A writable filesystem abstraction is not yet implemented as of Go 1.20. See
+// https://github.com/golang/go/issues/45757
+type FS interface {
+	// OpenFile opens a file. It should be closed via Close on File.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` or `flag` is invalid.
+	//   - EISDIR: the path was a directory, but flag included O_RDWR or
+	//     O_WRONLY
+	//   - ENOENT: `path` doesn't exist and `flag` doesn't contain O_CREAT.
+	//
+	// # Constraints on the returned file
+	//
+	// Implementations that can read flags should enforce them regardless of
+	// the type returned. For example, while os.File implements io.Writer,
+	// attempts to write to a directory or a file opened with O_RDONLY fail
+	// with a EBADF.
+	//
+	// Some implementations choose whether to enforce read-only opens, namely
+	// fs.FS. While fs.FS is supported (Adapt), wazero cannot runtime enforce
+	// open flags. Instead, we encourage good behavior and test our built-in
+	// implementations.
+	//
+	// # Notes
+	//
+	//   - This is like os.OpenFile, except the path is relative to this file
+	//     system, and Errno is returned instead of os.PathError.
+	//   - Implications of permissions when O_CREAT are described in Chmod notes.
+	//   - This is like `open` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/open.html
+	OpenFile(path string, flag Oflag, perm fs.FileMode) (File, Errno)
+
+	// Lstat gets file status without following symbolic links.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - ENOENT: `path` doesn't exist.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Lstat, except the `path` is relative to this
+	//     file system.
+	//   - This is like `lstat` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/lstat.html
+	//   - An fs.FileInfo backed implementation sets atim, mtim and ctim to the
+	//     same value.
+	//   - When the path is a symbolic link, the stat returned is for the link,
+	//     not the file it refers to.
+	Lstat(path string) (sys.Stat_t, Errno)
+
+	// Stat gets file status.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - ENOENT: `path` doesn't exist.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Stat, except the `path` is relative to this
+	//     file system.
+	//   - This is like `stat` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/stat.html
+	//   - An fs.FileInfo backed implementation sets atim, mtim and ctim to the
+	//     same value.
+	//   - When the path is a symbolic link, the stat returned is for the file
+	//     it refers to.
+	Stat(path string) (sys.Stat_t, Errno)
+
+	// Mkdir makes a directory.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` is invalid.
+	//   - EEXIST: `path` exists and is a directory.
+	//   - ENOTDIR: `path` exists and is a file.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Mkdir, except the `path` is relative to this
+	//     file system.
+	//   - This is like `mkdir` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/mkdir.html
+	//   - Implications of permissions are described in Chmod notes.
+	Mkdir(path string, perm fs.FileMode) Errno
+
+	// Chmod changes the mode of the file.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` is invalid.
+	//   - ENOENT: `path` does not exist.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Chmod, except the `path` is relative to this
+	//     file system.
+	//   - This is like `chmod` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/chmod.html
+	//   - Windows ignores the execute bit, and any permissions come back as
+	//     group and world. For example, chmod of 0400 reads back as 0444, and
+	//     0700 0666. Also, permissions on directories aren't supported at all.
+	Chmod(path string, perm fs.FileMode) Errno
+
+	// Rename renames file or directory.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `from` or `to` is invalid.
+	//   - ENOENT: `from` or `to` don't exist.
+	//   - ENOTDIR: `from` is a directory and `to` exists as a file.
+	//   - EISDIR: `from` is a file and `to` exists as a directory.
+	//   - ENOTEMPTY: `both from` and `to` are existing directory, but
+	//    `to` is not empty.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Rename, except the paths are relative to this
+	//     file system.
+	//   - This is like `rename` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/rename.html
+	//   -  Windows doesn't let you overwrite an existing directory.
+	Rename(from, to string) Errno
+
+	// Rmdir removes a directory.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` is invalid.
+	//   - ENOENT: `path` doesn't exist.
+	//   - ENOTDIR: `path` exists, but isn't a directory.
+	//   - ENOTEMPTY: `path` exists, but isn't empty.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Rmdir, except the `path` is relative to this
+	//     file system.
+	//   - This is like `rmdir` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/rmdir.html
+	//   - As of Go 1.19, Windows maps ENOTDIR to ENOENT.
+	Rmdir(path string) Errno
+
+	// Unlink removes a directory entry.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` is invalid.
+	//   - ENOENT: `path` doesn't exist.
+	//   - EISDIR: `path` exists, but is a directory.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Unlink, except the `path` is relative to this
+	//     file system.
+	//   - This is like `unlink` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/unlink.html
+	//   - On Windows, syscall.Unlink doesn't delete symlink to directory unlike other platforms. Implementations might
+	//     want to combine syscall.RemoveDirectory with syscall.Unlink in order to delete such links on Windows.
+	//     See https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-removedirectorya
+	Unlink(path string) Errno
+
+	// Link creates a "hard" link from oldPath to newPath, in contrast to a
+	// soft link (via Symlink).
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EPERM: `oldPath` is invalid.
+	//   - ENOENT: `oldPath` doesn't exist.
+	//   - EISDIR: `newPath` exists, but is a directory.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Link, except the `oldPath` is relative to this
+	//     file system.
+	//   - This is like `link` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/link.html
+	Link(oldPath, newPath string) Errno
+
+	// Symlink creates a "soft" link from oldPath to newPath, in contrast to a
+	// hard link (via Link).
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EPERM: `oldPath` or `newPath` is invalid.
+	//   - EEXIST: `newPath` exists.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Symlink, except the `oldPath` is relative to
+	//     this file system.
+	//   - This is like `symlink` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/symlink.html
+	//   - Only `newPath` is relative to this file system and `oldPath` is kept
+	//     as-is. That is because the link is only resolved relative to the
+	//     directory when dereferencing it (e.g. ReadLink).
+	//     See https://github.com/bytecodealliance/cap-std/blob/v1.0.4/cap-std/src/fs/dir.rs#L404-L409
+	//     for how others implement this.
+	//   - Symlinks in Windows requires `SeCreateSymbolicLinkPrivilege`.
+	//     Otherwise, EPERM results.
+	//     See https://learn.microsoft.com/en-us/windows/security/threat-protection/security-policy-settings/create-symbolic-links
+	Symlink(oldPath, linkName string) Errno
+
+	// Readlink reads the contents of a symbolic link.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` is invalid.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.Readlink, except the path is relative to this
+	//     filesystem.
+	//   - This is like `readlink` in POSIX. See
+	//     https://pubs.opengroup.org/onlinepubs/9699919799/functions/readlink.html
+	//   - On Windows, the path separator is different from other platforms,
+	//     but to provide consistent results to Wasm, this normalizes to a "/"
+	//     separator.
+	Readlink(path string) (string, Errno)
+
+	// Utimens set file access and modification times on a path relative to
+	// this file system, at nanosecond precision.
+	//
+	// # Parameters
+	//
+	// If the path is a symbolic link, the target of expanding that link is
+	// updated.
+	//
+	// The `atim` and `mtim` parameters refer to access and modification time
+	// stamps as defined in sys.Stat_t. To retain one or the other, substitute
+	// it with the pseudo-timestamp UTIME_OMIT.
+	//
+	// # Errors
+	//
+	// A zero Errno is success. The below are expected otherwise:
+	//   - ENOSYS: the implementation does not support this function.
+	//   - EINVAL: `path` is invalid.
+	//   - EEXIST: `path` exists and is a directory.
+	//   - ENOTDIR: `path` exists and is a file.
+	//
+	// # Notes
+	//
+	//   - This is like syscall.UtimesNano and `utimensat` with `AT_FDCWD` in
+	//     POSIX. See https://pubs.opengroup.org/onlinepubs/9699919799/functions/futimens.html
+	Utimens(path string, atim, mtim int64) Errno
+}