av_tempfile failed to create file on android

[chinshou]

Summary of the bug:
when using cache protocol on android to download the file to local.

android report ff_tempfile: Cannot open temporary file error.

[Carl Eugen Hoyos]

How can I reproduce this issue?

[Carl Eugen Hoyos]

Regression since fd6af5375bcf3f78c61e4b0ca2e4274436746436

$ ffmpeg -i cache:fate-suite/4xm/dracula.4xm
ffmpeg version N-80268-g9e9286e Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 4.9 (GCC) 20140827 (prerelease)
  configuration: --cross-prefix=../android-ndk-r10e/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi- --arch=arm --target-os=linux --sysroot=../android-ndk-r10e/platforms/android-17/arch-arm/ --enable-gpl --cpu=cortex-a8
  libavutil      55. 24.100 / 55. 24.100
  libavcodec     57. 46.100 / 57. 46.100
  libavformat    57. 37.101 / 57. 37.101
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 46.101 /  6. 46.101
  libswscale      4.  1.100 /  4.  1.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
[cache @ 0x158a7a0] [TEMPFILE @ 0xbeffeeec] ff_tempfile: Cannot open temporary file /tmp/ffcacheSW7060
[cache @ 0x158a7a0] Failed to create tempfile
cache:fate-suite/4xm/dracula.4xm: Permission denied

[Michael Niedermayer]

try adding || defined(__ANDROID__)
and maybe try /sdcard in adition to /tmp
android is messy from a linux/posix point of view

[Carl Eugen Hoyos]

The following works as expected:

diff --git a/libavutil/file_open.c b/libavutil/file_open.c
index 6e58cc1..34070d9 100644
--- a/libavutil/file_open.c
+++ b/libavutil/file_open.c
@@ -134,7 +134,7 @@ int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *l
 #else
     snprintf(*filename, len, "/tmp/%sXXXXXX", prefix);
     fd = mkstemp(*filename);
-#ifdef _WIN32
+#if defined(_WIN32) || defined (__ANDROID__)
     if (fd < 0) {
         snprintf(*filename, len, "./%sXXXXXX", prefix);
         fd = mkstemp(*filename);

/sdcard leads to an error message when testing:

$ ffmpeg -i cache:fate-suite/4xm/dracula.4xm
ffmpeg version N-80268-g9e9286e Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 4.9 (GCC) 20140827 (prerelease)
  configuration: --cross-prefix=../android-ndk-r10e/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi- --arch=arm --target-os=linux --sysroot=../android-ndk-r10e/platforms/android-17/arch-arm/ --enable-gpl --cpu=cortex-a8
  libavutil      55. 24.100 / 55. 24.100
  libavcodec     57. 46.100 / 57. 46.100
  libavformat    57. 37.101 / 57. 37.101
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 46.101 /  6. 46.101
  libswscale      4.  1.100 /  4.  1.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
[cache @ 0x158a7a0] seek in cache failed
    Last message repeated 2 times
[4xm @ 0x158a0f0] Estimating duration from bitrate, this may be inaccurate
Guessed Channel Layout for  Input Stream #0.1 : stereo
Guessed Channel Layout for  Input Stream #0.2 : stereo
Guessed Channel Layout for  Input Stream #0.3 : stereo
Guessed Channel Layout for  Input Stream #0.4 : stereo
Guessed Channel Layout for  Input Stream #0.5 : stereo
Guessed Channel Layout for  Input Stream #0.6 : stereo
Input #0, 4xm, from 'cache:fate-suite/4xm/dracula.4xm':
  Duration: 00:00:01.93, start: 0.000000, bitrate: 4236 kb/s
    Stream #0:0: Video: 4xm, rgb565le, 640x480, 15 tbr, 15 tbn, 15 tbc
    Stream #0:1: Audio: adpcm_4xm, 22050 Hz, 2 channels, s16p, 705 kb/s
    Stream #0:2: Audio: adpcm_4xm, 22050 Hz, 2 channels, s16p, 705 kb/s
    Stream #0:3: Audio: adpcm_4xm, 22050 Hz, 2 channels, s16p, 705 kb/s
    Stream #0:4: Audio: adpcm_4xm, 22050 Hz, 2 channels, s16p, 705 kb/s
    Stream #0:5: Audio: adpcm_4xm, 22050 Hz, 2 channels, s16p, 705 kb/s
    Stream #0:6: Audio: adpcm_4xm, 22050 Hz, 2 channels, s16p, 705 kb/s
At least one output file must be specified
[cache @ 0x158a7a0] Statistics, cache hits:0 cache misses:3

diff --git a/libavutil/file_open.c b/libavutil/file_open.c
index 6e58cc1..4d05267 100644
--- a/libavutil/file_open.c
+++ b/libavutil/file_open.c
@@ -132,7 +132,7 @@ int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *l
 #   endif
     fd = open(*filename, O_RDWR | O_BINARY | O_CREAT | O_EXCL, 0600);
 #else
-    snprintf(*filename, len, "/tmp/%sXXXXXX", prefix);
+    snprintf(*filename, len, "/sdcard/%sXXXXXX", prefix);
     fd = mkstemp(*filename);
 #ifdef _WIN32
     if (fd < 0) {

[Michael Niedermayer]

Replying to cehoyos:

The following works as expected:

diff --git a/libavutil/file_open.c b/libavutil/file_open.c
index 6e58cc1..34070d9 100644
--- a/libavutil/file_open.c
+++ b/libavutil/file_open.c
@@ -134,7 +134,7 @@ int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *l
 #else
     snprintf(*filename, len, "/tmp/%sXXXXXX", prefix);
     fd = mkstemp(*filename);
-#ifdef _WIN32
+#if defined(_WIN32) || defined (__ANDROID__)
     if (fd < 0) {
         snprintf(*filename, len, "./%sXXXXXX", prefix);
         fd = mkstemp(*filename);

please submit this to ffmpeg-devel if you agree that it is a acceptable solution

[Carl Eugen Hoyos]

Should be fixed in 4c9d1c6f9a8f166703dc0333b53f5dba8dc5b414