Backed out changesets bde36c2eacc0 and 8dc40bbe844e (bug 862088) for causing bug 875769.

toolkit/components/mediasniffer/Makefile.in

@@ -21,9 +21,5 @@ CPPSRCS = \
     nsMediaSnifferModule.cpp \
     $(NULL)
 
-CSRCS = \
-    mp3sniff.c
-    $(NULL)
-
 include $(topsrcdir)/config/config.mk
 include $(topsrcdir)/config/rules.mk

toolkit/components/mediasniffer/mp3sniff.c

@@ -1,166 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/* MPEG format parsing */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
-
-#include "mp3sniff.h"
-
-/* Maximum packet size is 320 kbits/s * 144 / 32 kHz + 1 padding byte */
-#define MP3_MAX_SIZE 1441
-
-typedef struct {
-  int version;
-  int layer;
-  int errp;
-  int bitrate;
-  int freq;
-  int pad;
-  int priv;
-  int mode;
-  int modex;
-  int copyright;
-  int original;
-  int emphasis;
-} mp3_header;
-
-/* Parse the 4-byte header in p and fill in the header struct. */
-static void mp3_parse(const uint8_t *p, mp3_header *header)
-{
-  const int bitrates[16] =
-	{0,  32000,  40000,  48000,  56000,  64000,  80000,  96000,
-         112000, 128000, 160000, 192000, 224000, 256000, 320000, 0};
-  const int samplerates[4] = {44100, 48000, 32000, 0};
-
-  header->version = (p[1] & 0x08) >> 3;
-  header->layer = 4 - ((p[1] & 0x06) >> 1);
-  header->errp = (p[1] & 0x01);
-
-  header->bitrate = bitrates[(p[2] & 0xf0) >> 4];
-  header->freq = samplerates[(p[2] & 0x0c) >> 2];
-  header->pad = (p[2] & 0x02) >> 1;
-  header->priv = (p[2] & 0x01);
-
-  header->mode = (p[3] & 0xc0) >> 6;
-  header->modex = (p[3] & 0x30) >> 4;
-  header->copyright = (p[3] & 0x08) >> 3;
-  header->original = (p[3] & 0x04) >> 2;
-  header->emphasis = (p[3] & 0x03);
-}
-
-/* calculate the size of an mp3 frame from its header */
-static int mp3_framesize(mp3_header *header)
-{
-  int size;
-  int scale;
-
-  if (header->layer == 1) scale = 48;
-  else scale = 144;
-
-  size = header->bitrate * scale / header->freq;
-  /* divide by an extra factor of 2 for MPEG-2? */
-
-  if (header->pad) size += 1;
-
-  return size;
-}
-
-static int is_mp3(const uint8_t *p, long length) {
-  /* Do we have enough room to see a 4 byte header? */
-  if (length < 4) return 0;
-  /* Do we have a sync pattern? */
-  if (p[0] == 0xff && (p[1]&0xe0) == 0xe0) {
-    /* Do we have any illegal field values? */
-    if (((p[1] & 0x06) >> 1) == 0) return 0;  /* No layer 4 */
-    if (((p[2] & 0xf0) >> 4) == 15) return 0; /* Bitrate can't be 1111 */
-    if (((p[2] & 0x0c) >> 2) == 3) return 0;  /* Samplerate can't be 11 */
-    /* Looks like a header. */
-    return 1;
-  }
-  return 0;
-}
-
-/* Identify an ID3 tag based on its header. */
-/* http://id3.org/id3v2.4.0-structure */
-static int is_id3(const uint8_t *p, long length) {
-  /* Do we have enough room to see the header? */
-  if (length < 10) return 0;
-  /* Do we have a sync pattern? */
-  if (p[0] == 'I' && p[1] == 'D' && p[2] == '3') {
-    if (p[3] == 0xff || p[4] == 0xff) return 0; /* Illegal version. */
-    if (p[6] & 0x80 || p[7] & 0x80 ||
-        p[8] & 0x80) return 0; /* Bad length encoding. */
-    /* Looks like an id3 header. */
-    return 1;
-  }
-  return 0;
-}
-
-/* Calculate the size of an id3 tag structure from its header. */
-static int id3_framesize(const uint8_t *p, long length)
-{
-  int size;
-
-  /* Header is 10 bytes. */
-  if (length < 10) {
-    return 0;
-  }
-  /* Frame is header plus declared size. */
-  size = 10 + (p[9] | (p[8] << 7) | (p[7] << 14) | (p[6] << 21));
-
-  return size;
-}
-
-int mp3_sniff(const uint8_t *buf, long length)
-{
-  mp3_header header;
-  const uint8_t *p, *q;
-  long skip;
-  long avail;
-
-  p = buf;
-  q = p;
-  avail = length;
-  while (avail > 0) {
-    if (is_id3(p, avail)) {
-      /* Skip over any id3 tags */
-      skip = id3_framesize(p, avail);
-      p += skip;
-      avail -= skip;
-      /* Is there enough data to continue? */
-      if (skip + 4 > avail) {
-        return 0;
-      }
-    } else if (is_mp3(p, avail)) {
-      mp3_parse(p, &header);
-      skip = mp3_framesize(&header);
-      if (skip + 4 > avail) {
-        return 0;
-      }
-      p += skip;
-      avail -= skip;
-      /* Check for a second header at the expected offset. */
-      if (is_mp3(p, avail)) {
-         /* Looks like mp3. */
-        return 1;
-      } else {
-        /* Give up. */
-        return 0;
-      }
-    } else {
-      /* Advance one byte and look for sync again. */
-      p++;
-      avail--;
-      /* Don't scan for more than the maximum frame size. */
-      if (length - avail > MP3_MAX_SIZE) {
-        return 0;
-      }
-    }
-  }
-
-  return 0;
-}

toolkit/components/mediasniffer/mp3sniff.h

@@ -1,15 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include <stdint.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-int mp3_sniff(const uint8_t *buf, long length);
-
-#ifdef __cplusplus
-}
-#endif

toolkit/components/mediasniffer/nsMediaSniffer.cpp

@@ -10,7 +10,6 @@
 #include "nsString.h"
 #include "nsMimeTypes.h"
 #include "mozilla/ModuleUtils.h"
-#include "mp3sniff.h"
 #ifdef MOZ_WEBM
 #include "nestegg/nestegg.h"
 #endif
@@ -85,13 +84,6 @@ static bool MatchesWebM(const uint8_t* aData, const uint32_t aLength)
 #endif
 }
 
-// This function implements mp3 sniffing based on parsing
-// packet headers and looking for expected boundaries.
-static bool MatchesMP3(const uint8_t* aData, const uint32_t aLength)
-{
-  return mp3_sniff(aData, (long)aLength);
-}
-
 NS_IMETHODIMP
 nsMediaSniffer::GetMIMETypeFromContent(nsIRequest* aRequest,
                                        const uint8_t* aData,
@@ -142,11 +134,6 @@ nsMediaSniffer::GetMIMETypeFromContent(nsIRequest* aRequest,
     return NS_OK;
   }
 
-  if (MatchesMP3(aData, clampedLength)) {
-    aSniffedType.AssignLiteral(AUDIO_MP3);
-    return NS_OK;
-  }
-
   // Could not sniff the media type, we are required to set it to
   // application/octet-stream.
   aSniffedType.AssignLiteral(APPLICATION_OCTET_STREAM);

toolkit/components/mediasniffer/test/unit/test_mediasniffer_webm.js

@@ -18,23 +18,15 @@ var httpserver = new HttpServer();
 var testRan = 0;
 
 // The tests files we want to test, and the type we should have after sniffing.
+// Those file are real webm and mkv files truncated to 512 bytes.
 const tests = [
-  // Real webm and mkv files truncated to 512 bytes.
   { path: "data/file.webm", expected: "video/webm" },
   { path: "data/file.mkv", expected: "application/octet-stream" },
-  // MP3 files with and without id3 headers truncated to 512 bytes.
-  // NB these have 208/209 byte frames, but mp3 can require up to
-  // 1445 bytes to detect with our method.
-  { path: "data/id3tags.mp3", expected: "audio/mpeg" },
-  { path: "data/notags.mp3", expected: "audio/mpeg" },
-  // Padding bit flipped in the first header: sniffing should fail.
-  { path: "data/notags-bad.mp3", expected: "application/octet-stream" },
 ];
 
 // A basic listener that reads checks the if we sniffed properly.
 var listener = {
   onStartRequest: function(request, context) {
-    do_print("Sniffing " + tests[testRan].path);
     do_check_eq(request.QueryInterface(Ci.nsIChannel).contentType, tests[testRan].expected);
   },
 

toolkit/components/mediasniffer/test/unit/xpcshell.ini

@@ -3,4 +3,4 @@ head =
 tail =
 
 [test_mediasniffer.js]
-[test_mediasniffer_ext.js]
+[test_mediasniffer_webm.js]