[feature] support processing of (many) more media types (#3090)

* initial work replacing our media decoding / encoding pipeline with ffprobe + ffmpeg

* specify the video codec to use when generating static image from emoji

* update go-storage library (fixes incompatibility after updating go-iotools)

* maintain image aspect ratio when generating a thumbnail for it

* update readme to show go-ffmpreg

* fix a bunch of media tests, move filesize checking to callers of media manager for more flexibility

* remove extra debug from error message

* fix up incorrect function signatures

* update PutFile to just use regular file copy, as changes are file is on separate partition

* fix remaining tests, remove some unneeded tests now we're working with ffmpeg/ffprobe

* update more tests, add more code comments

* add utilities to generate processed emoji / media outputs

* fix remaining tests

* add test for opus media file, add license header to utility cmds

* limit the number of concurrently available ffmpeg / ffprobe instances

* reduce number of instances

* further reduce number of instances

* fix envparsing test with configuration variables

* update docs and configuration with new media-{local,remote}-max-size variables

vendor/github.com/tetratelabs/wazero/internal/wasip1/fs.go

@@ -0,0 +1,164 @@
+package wasip1
+
+import (
+	"fmt"
+)
+
+const (
+	FdAdviseName           = "fd_advise"
+	FdAllocateName         = "fd_allocate"
+	FdCloseName            = "fd_close"
+	FdDatasyncName         = "fd_datasync"
+	FdFdstatGetName        = "fd_fdstat_get"
+	FdFdstatSetFlagsName   = "fd_fdstat_set_flags"
+	FdFdstatSetRightsName  = "fd_fdstat_set_rights"
+	FdFilestatGetName      = "fd_filestat_get"
+	FdFilestatSetSizeName  = "fd_filestat_set_size"
+	FdFilestatSetTimesName = "fd_filestat_set_times"
+	FdPreadName            = "fd_pread"
+	FdPrestatGetName       = "fd_prestat_get"
+	FdPrestatDirNameName   = "fd_prestat_dir_name"
+	FdPwriteName           = "fd_pwrite"
+	FdReadName             = "fd_read"
+	FdReaddirName          = "fd_readdir"
+	FdRenumberName         = "fd_renumber"
+	FdSeekName             = "fd_seek"
+	FdSyncName             = "fd_sync"
+	FdTellName             = "fd_tell"
+	FdWriteName            = "fd_write"
+
+	PathCreateDirectoryName  = "path_create_directory"
+	PathFilestatGetName      = "path_filestat_get"
+	PathFilestatSetTimesName = "path_filestat_set_times"
+	PathLinkName             = "path_link"
+	PathOpenName             = "path_open"
+	PathReadlinkName         = "path_readlink"
+	PathRemoveDirectoryName  = "path_remove_directory"
+	PathRenameName           = "path_rename"
+	PathSymlinkName          = "path_symlink"
+	PathUnlinkFileName       = "path_unlink_file"
+)
+
+// oflags are open flags used by path_open
+// See https://github.com/WebAssembly/WASI/blob/snapshot-01/phases/snapshot/docs.md#-oflags-flagsu16
+const (
+	// O_CREAT creates a file if it does not exist.
+	O_CREAT uint16 = 1 << iota //nolint
+	// O_DIRECTORY fails if not a directory.
+	O_DIRECTORY
+	// O_EXCL fails if file already exists.
+	O_EXCL //nolint
+	// O_TRUNC truncates the file to size 0.
+	O_TRUNC //nolint
+)
+
+func OflagsString(oflags int) string {
+	return flagsString(oflagNames[:], oflags)
+}
+
+var oflagNames = [...]string{
+	"CREAT",
+	"DIRECTORY",
+	"EXCL",
+	"TRUNC",
+}
+
+// file descriptor flags
+// See https://github.com/WebAssembly/WASI/blob/snapshot-01/phases/snapshot/docs.md#fdflags
+const (
+	FD_APPEND uint16 = 1 << iota //nolint
+	FD_DSYNC
+	FD_NONBLOCK
+	FD_RSYNC
+	FD_SYNC
+)
+
+func FdFlagsString(fdflags int) string {
+	return flagsString(fdflagNames[:], fdflags)
+}
+
+var fdflagNames = [...]string{
+	"APPEND",
+	"DSYNC",
+	"NONBLOCK",
+	"RSYNC",
+	"SYNC",
+}
+
+// See https://github.com/WebAssembly/WASI/blob/snapshot-01/phases/snapshot/docs.md#lookupflags
+const (
+	// LOOKUP_SYMLINK_FOLLOW expands a path if it resolves into a symbolic
+	// link.
+	LOOKUP_SYMLINK_FOLLOW uint16 = 1 << iota //nolint
+)
+
+var lookupflagNames = [...]string{
+	"SYMLINK_FOLLOW",
+}
+
+func LookupflagsString(lookupflags int) string {
+	return flagsString(lookupflagNames[:], lookupflags)
+}
+
+// DirentSize is the size of the dirent struct, which should be followed by the
+// length of a file name.
+const DirentSize = uint32(24)
+
+const (
+	FILETYPE_UNKNOWN uint8 = iota
+	FILETYPE_BLOCK_DEVICE
+	FILETYPE_CHARACTER_DEVICE
+	FILETYPE_DIRECTORY
+	FILETYPE_REGULAR_FILE
+	FILETYPE_SOCKET_DGRAM
+	FILETYPE_SOCKET_STREAM
+	FILETYPE_SYMBOLIC_LINK
+)
+
+// FiletypeName returns string name of the file type.
+func FiletypeName(filetype uint8) string {
+	if int(filetype) < len(filetypeToString) {
+		return filetypeToString[filetype]
+	}
+	return fmt.Sprintf("filetype(%d)", filetype)
+}
+
+var filetypeToString = [...]string{
+	"UNKNOWN",
+	"BLOCK_DEVICE",
+	"CHARACTER_DEVICE",
+	"DIRECTORY",
+	"REGULAR_FILE",
+	"SOCKET_DGRAM",
+	"SOCKET_STREAM",
+	"SYMBOLIC_LINK",
+}
+
+// https://github.com/WebAssembly/WASI/blob/snapshot-01/phases/snapshot/docs.md#fstflags
+const (
+	FstflagsAtim uint16 = 1 << iota
+	FstflagsAtimNow
+	FstflagsMtim
+	FstflagsMtimNow
+)
+
+var fstflagNames = [...]string{
+	"ATIM",
+	"ATIM_NOW",
+	"MTIM",
+	"MTIM_NOW",
+}
+
+func FstflagsString(fdflags int) string {
+	return flagsString(fstflagNames[:], fdflags)
+}
+
+// https://github.com/WebAssembly/WASI/blob/snapshot-01/phases/snapshot/docs.md#-advice-enumu8
+const (
+	FdAdviceNormal byte = iota
+	FdAdviceSequential
+	FdAdviceRandom
+	FdAdviceWillNeed
+	FdAdviceDontNeed
+	FdAdviceNoReuse
+)