给VLC打补丁, 使flac网络文件/流的Content-Type始终为"audio/flac", 以"修复"网易云音乐获取的flac网络文件Content-Type为"audio/mpeg"而导致VLC不能正确识别文件而播放失败的问题

ncm.patch

diff --git a/modules/access/http/resource.c b/modules/access/http/resource.c
index 9a28bb50f3..4919cb3a05 100644
--- a/modules/access/http/resource.c
+++ b/modules/access/http/resource.c
@@ -315,6 +315,18 @@ char *vlc_http_res_get_type(struct vlc_http_resource *res)
     if (status < 200 || status >= 300)
         return NULL;
 
+    if(res->path){
+        char *suffix = "\0";
+        for(int i = (int) (strlen(res->path) - 1); i >= 0; --i){
+            if(res->path[i] == '.'){
+                suffix = res->path + i + 1;
+                break;
+            }
+        }
+        if(strcmp(suffix, "flac") == 0)
+            return strdup("audio/flac");
+    }
+
     const char *type = vlc_http_msg_get_header(res->response, "Content-Type");
     return (type != NULL) ? strdup(type) : NULL;
 }

PKGBUILD

_pkgname=vlc
pkgname=vlc-ncm
_vlcver=3.0.12
# optional fixup version including hyphen
_vlcfixupver=
pkgver=${_vlcver}${_vlcfixupver//-/.r}
pkgrel=1
pkgdesc='Multi-platform MPEG, VCD/DVD, and DivX player'
url='https://www.videolan.org/vlc/'
arch=('x86_64')
license=('LGPL2.1' 'GPL2')
depends=('flac' 'mpg123' 'libpulse' 'alsa-lib' 'libsamplerate' 'libsoxr')
makedepends=()
options=('!emptydirs')
source=(https://download.videolan.org/${_pkgname}/${_vlcver}/${_pkgname}-${_vlcver}${_vlcfixupver}.tar.xz{,.asc}
        ncm.patch)
sha512sums=('ebec92bf732540be117551e94613747c53514ade7e280167c08400375738df9a01ee0e5d7c7733aca151a4f80f1c7163fd41318f2cc80b04a3201f0ba697e5df'
            'SKIP'
            '0dd7a8a140173af3d43a86edab709128a5ee5ec05323425067ae4f8db937c104d086695ff4dc97763a550fb3e6cb4c4e0174673bc032bb04dae37451741a5b15')
validpgpkeys=('65F7C6B4206BD057A7EB73787180713BE58D1ADC') # VideoLAN Release Signing Key

prepare() {
  cd ${_pkgname}-${_vlcver}
  sed -e 's:truetype/ttf-dejavu:TTF:g' -i modules/visualization/projectm.cpp
  sed -e 's|-Werror-implicit-function-declaration||g' -i configure
  sed 's|whoami|echo builduser|g' -i configure
  sed 's|hostname -f|echo arch|g' -i configure
  local src
  for src in "${source[@]}"; do
    src="${src%%::*}"
    src="${src##*/}"
    [[ $src = *.patch ]] || continue
    echo "Applying patch $src..."
    patch -Np1 < "../$src"
  done
}

build() {
  cd ${_pkgname}-${_vlcver}

  export CXXFLAGS+=" -std=c++11"

  ./configure \
    --prefix=/opt/vlc-ncm \
    --sysconfdir=/opt/vlc-ncm/etc \
    --disable-rpath \
    --enable-mpg123 \
    --enable-flac \
    --disable-pulse \
    --enable-alsa \
    --enable-samplerate \
    --enable-soxr \
    --enable-gnutls \
    --disable-update-check \
    --disable-vlc \
    --disable-lua \
    --disable-avcodec \
    --disable-avformat \
    --disable-gst-decode \
    --disable-swscale \
    --disable-a52 \
    --without-x \
    --disable-xcb \
    --disable-vdpau \
    --disable-wayland \
    --disable-sdl-image \
    --disable-srt \
    --disable-qt \
    --disable-caca

  make
}

package() {
  cd ${_pkgname}-${_vlcver}

  make DESTDIR="${pkgdir}" install

  install -Dm 644 "${srcdir}/update-vlc-ncm-plugin-cache.hook" -t "${pkgdir}/usr/share/libalpm/hooks"
}

# vim: ts=2 sw=2 et:

此PKGBUILD只在clean chroot中构建通过，在用户环境下可能需要自行调整构建选项。
如果有卡顿可以尝试关闭pulseaudio后端( --enable-pulse -> --disable-pulse) 只留下ALSA后端。