#468 WAV files with RIFF and data chunk sizes of zero

#468
Attempt to guess appropriate values for RIFF and RIFF.data size fields when fields are zero.

Author: JamesHeinrich

getid3/getid3.php

@@ -387,7 +387,7 @@ class getID3
 	 */
 	protected $startup_warning = '';
 
-	const VERSION           = '1.9.23-202502021530';
+	const VERSION           = '1.9.23-202509032051';
 	const FREAD_BUFFER_SIZE = 32768;
 
 	const ATTACHMENTS_NONE   = false;

getid3/module.audio-video.riff.php

@@ -67,12 +67,19 @@ public function Analyze() {
 		$RIFFsize    = substr($RIFFheader, 4, 4);
 		$RIFFsubtype = substr($RIFFheader, 8, 4);
 
-		switch ($RIFFtype) {
+		if ($RIFFsize == "\x00\x00\x00\x00") {
+			// https://github.com/JamesHeinrich/getID3/issues/468
+			// may occur in streaming files where the data size is unknown
+			$thisfile_riff['header_size'] = $info['avdataend'] - 8;
+			$this->warning('RIFF size field is empty, assuming the correct value is filesize-8 ('.$thisfile_riff['header_size'].')');
+		} else {
+			$thisfile_riff['header_size'] = $this->EitherEndian2Int($RIFFsize);
+		}
 
+		switch ($RIFFtype) {
 			case 'FORM':  // AIFF, AIFC
 				//$info['fileformat']   = 'aiff';
 				$this->container = 'aiff';
-				$thisfile_riff['header_size'] = $this->EitherEndian2Int($RIFFsize);
 				$thisfile_riff[$RIFFsubtype]  = $this->ParseRIFF($offset, ($offset + $thisfile_riff['header_size'] - 4));
 				break;
 
@@ -81,7 +88,6 @@ public function Analyze() {
 			case 'RMP3':  // RMP3 is identical to RIFF, just renamed. Used by [unknown program] when creating RIFF-MP3s
 				//$info['fileformat']   = 'riff';
 				$this->container = 'riff';
-				$thisfile_riff['header_size'] = $this->EitherEndian2Int($RIFFsize);
 				if ($RIFFsubtype == 'RMP3') {
 					// RMP3 is identical to WAVE, just renamed. Used by [unknown program] when creating RIFF-MP3s
 					$RIFFsubtype = 'WAVE';
@@ -1606,9 +1612,18 @@ public function ParseRIFF($startoffset, $maxoffset) {
 					$this->error('Expecting chunk name at offset '.($this->ftell() - 8).' but found nothing. Aborting RIFF parsing.');
 					break;
 				}
-				if (($chunksize == 0) && ($chunkname != 'JUNK')) {
-					$this->warning('Chunk ('.$chunkname.') size at offset '.($this->ftell() - 4).' is zero. Aborting RIFF parsing.');
-					break;
+				if ($chunksize == 0) {
+					if ($chunkname == 'JUNK') {
+						// this is allowed
+					} elseif ($chunkname == 'data') {
+						// https://github.com/JamesHeinrich/getID3/issues/468
+						// may occur in streaming files where the data size is unknown
+						$chunksize = $info['avdataend'] - $this->ftell();
+						$this->warning('RIFF.data size field is empty, assuming the correct value is filesize-offset ('.$chunksize.')');
+					} else {
+						$this->warning('Chunk ('.$chunkname.') size at offset '.($this->ftell() - 4).' is zero. Aborting RIFF parsing.');
+						break;
+					}
 				}
 				if (($chunksize % 2) != 0) {
 					// all structures are packed on word boundaries