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text.go
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text.go
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package magic
import (
"bytes"
"github.com/gabriel-vasile/mimetype/internal/charset"
"github.com/gabriel-vasile/mimetype/internal/json"
)
var (
// Html matches a Hypertext Markup Language file.
Html = markup(
[]byte("<!DOCTYPE HTML"),
[]byte("<HTML"),
[]byte("<HEAD"),
[]byte("<SCRIPT"),
[]byte("<IFRAME"),
[]byte("<H1"),
[]byte("<DIV"),
[]byte("<FONT"),
[]byte("<TABLE"),
[]byte("<A"),
[]byte("<STYLE"),
[]byte("<TITLE"),
[]byte("<B"),
[]byte("<BODY"),
[]byte("<BR"),
[]byte("<P"),
[]byte("<!--"),
)
// Xml matches an Extensible Markup Language file.
Xml = markup([]byte("<?XML"))
// Owl2 matches an Owl ontology file.
Owl2 = xml(newXmlSig("Ontology", `xmlns="http://www.w3.org/2002/07/owl#"`))
// Rss matches a Rich Site Summary file.
Rss = xml(newXmlSig("rss", ""))
// Atom matches an Atom Syndication Format file.
Atom = xml(newXmlSig("feed", `xmlns="http://www.w3.org/2005/Atom"`))
// Kml matches a Keyhole Markup Language file.
Kml = xml(
newXmlSig("kml", `xmlns="http://www.opengis.net/kml/2.2"`),
newXmlSig("kml", `xmlns="http://earth.google.com/kml/2.0"`),
newXmlSig("kml", `xmlns="http://earth.google.com/kml/2.1"`),
newXmlSig("kml", `xmlns="http://earth.google.com/kml/2.2"`),
)
// Xliff matches a XML Localization Interchange File Format file.
Xliff = xml(newXmlSig("xliff", `xmlns="urn:oasis:names:tc:xliff:document:1.2"`))
// Collada matches a COLLAborative Design Activity file.
Collada = xml(newXmlSig("COLLADA", `xmlns="http://www.collada.org/2005/11/COLLADASchema"`))
// Gml matches a Geography Markup Language file.
Gml = xml(
newXmlSig("", `xmlns:gml="http://www.opengis.net/gml"`),
newXmlSig("", `xmlns:gml="http://www.opengis.net/gml/3.2"`),
newXmlSig("", `xmlns:gml="http://www.opengis.net/gml/3.3/exr"`),
)
// Gpx matches a GPS Exchange Format file.
Gpx = xml(newXmlSig("gpx", `xmlns="http://www.topografix.com/GPX/1/1"`))
// Tcx matches a Training Center XML file.
Tcx = xml(newXmlSig("TrainingCenterDatabase", `xmlns="http://www.garmin.com/xmlschemas/TrainingCenterDatabase/v2"`))
// X3d matches an Extensible 3D Graphics file.
X3d = xml(newXmlSig("X3D", `xmlns:xsd="http://www.w3.org/2001/XMLSchema-instance"`))
// Amf matches an Additive Manufacturing XML file.
Amf = xml(newXmlSig("amf", ""))
// Threemf matches a 3D Manufacturing Format file.
Threemf = xml(newXmlSig("model", `xmlns="http://schemas.microsoft.com/3dmanufacturing/core/2015/02"`))
// Xfdf matches a XML Forms Data Format file.
Xfdf = xml(newXmlSig("xfdf", `xmlns="http://ns.adobe.com/xfdf/"`))
// VCard matches a Virtual Contact File.
VCard = ciPrefix([]byte("BEGIN:VCARD\n"), []byte("BEGIN:VCARD\r\n"))
// ICalendar matches a iCalendar file.
ICalendar = ciPrefix([]byte("BEGIN:VCALENDAR\n"), []byte("BEGIN:VCALENDAR\r\n"))
phpPageF = ciPrefix(
[]byte("<?PHP"),
[]byte("<?\n"),
[]byte("<?\r"),
[]byte("<? "),
)
phpScriptF = shebang(
[]byte("/usr/local/bin/php"),
[]byte("/usr/bin/php"),
[]byte("/usr/bin/env php"),
)
// Js matches a Javascript file.
Js = shebang(
[]byte("/bin/node"),
[]byte("/usr/bin/node"),
[]byte("/bin/nodejs"),
[]byte("/usr/bin/nodejs"),
[]byte("/usr/bin/env node"),
[]byte("/usr/bin/env nodejs"),
)
// Lua matches a Lua programming language file.
Lua = shebang(
[]byte("/usr/bin/lua"),
[]byte("/usr/local/bin/lua"),
[]byte("/usr/bin/env lua"),
)
// Perl matches a Perl programming language file.
Perl = shebang(
[]byte("/usr/bin/perl"),
[]byte("/usr/bin/env perl"),
)
// Python matches a Python programming language file.
Python = shebang(
[]byte("/usr/bin/python"),
[]byte("/usr/local/bin/python"),
[]byte("/usr/bin/env python"),
)
// Tcl matches a Tcl programming language file.
Tcl = shebang(
[]byte("/usr/bin/tcl"),
[]byte("/usr/local/bin/tcl"),
[]byte("/usr/bin/env tcl"),
[]byte("/usr/bin/tclsh"),
[]byte("/usr/local/bin/tclsh"),
[]byte("/usr/bin/env tclsh"),
[]byte("/usr/bin/wish"),
[]byte("/usr/local/bin/wish"),
[]byte("/usr/bin/env wish"),
)
// Rtf matches a Rich Text Format file.
Rtf = prefix([]byte("{\\rtf1"))
)
// Text matches a plain text file.
//
// TODO: This function does not parse BOM-less UTF16 and UTF32 files. Not really
// sure it should. Linux file utility also requires a BOM for UTF16 and UTF32.
func Text(raw []byte, limit uint32) bool {
// First look for BOM.
if cset := charset.FromBOM(raw); cset != "" {
return true
}
return isText(raw)
}
// Php matches a PHP: Hypertext Preprocessor file.
func Php(raw []byte, limit uint32) bool {
if res := phpPageF(raw, limit); res {
return res
}
return phpScriptF(raw, limit)
}
// Json matches a JavaScript Object Notation file.
func Json(raw []byte, limit uint32) bool {
parsed, err := json.Scan(raw)
if len(raw) < int(limit) {
return err == nil
}
return parsed == len(raw) && len(raw) > 0
}
// GeoJson matches a RFC 7946 GeoJSON file.
//
// GeoJson detection implies searching for key:value pairs like: `"type": "Feature"`
// in the input.
// BUG(gabriel-vasile): The "type" key should be searched for in the root object.
func GeoJson(raw []byte, limit uint32) bool {
raw = trimLWS(raw)
if len(raw) == 0 {
return false
}
// GeoJSON is always a JSON object, not a JSON array.
if raw[0] != '{' {
return false
}
s := []byte(`"type"`)
si, sl := bytes.Index(raw, s), len(s)
if si == -1 {
return false
}
// If the "type" string is the suffix of the input,
// there is no need to search for the value of the key.
if si+sl == len(raw) {
return false
}
// Skip the "type" part.
raw = raw[si+sl:]
// Skip any whitespace before the colon.
raw = trimLWS(raw)
// Check for colon.
if len(raw) == 0 || raw[0] != ':' {
return false
}
// Skip any whitespace after the colon.
raw = trimLWS(raw[1:])
geoJsonTypes := [][]byte{
[]byte(`"Feature"`),
[]byte(`"FeatureCollection"`),
[]byte(`"Point"`),
[]byte(`"LineString"`),
[]byte(`"Polygon"`),
[]byte(`"MultiPoint"`),
[]byte(`"MultiLineString"`),
[]byte(`"MultiPolygon"`),
[]byte(`"GeometryCollection"`),
}
for _, t := range geoJsonTypes {
if bytes.HasPrefix(raw, t) {
return true
}
}
return false
}
// NdJson matches a Newline delimited JSON file.
func NdJson(raw []byte, limit uint32) bool {
// Separator with carriage return and new line `\r\n`.
srn := []byte{0x0D, 0x0A}
// Separator with only new line `\n`.
sn := []byte{0x0A}
// Total bytes scanned.
parsed := 0
// Split by `srn`.
for rni, insrn := range bytes.Split(raw, srn) {
// Separator byte count should be added only after the first split.
if rni != 0 {
// Add two as `\r\n` is used for split.
parsed += 2
}
// Split again by `sn`.
for ni, insn := range bytes.Split(insrn, sn) {
// Separator byte count should be added only after the first split.
if ni != 0 {
// Add one as `\n` is used for split.
parsed++
}
// Empty line is valid.
if len(insn) == 0 {
continue
}
p, err := json.Scan(insn)
parsed += p
if parsed < int(limit) && err != nil {
return false
}
}
}
// Empty inputs should not pass as valid NDJSON with 0 lines.
return parsed > 2 && parsed == len(raw)
}
// Svg matches a SVG file.
func Svg(raw []byte, limit uint32) bool {
return bytes.Contains(raw, []byte("<svg"))
}
// isText considers any file containing null bytes as a binary file.
// There is plenty room for disagreement regarding what should be considered a
// text file. This approach is used by diff, cat, and other linux utilities.
func isText(raw []byte) bool {
l := 8000
if len(raw) > l {
raw = raw[:l]
}
return bytes.IndexByte(raw, 0) == -1
}