Fix usage of temp_file flag in hls_flags option.

This is a regression introduced by 223d2bde22.
It appears that regression was introduced in 4.1, 4.0.x does not share
this behaviour.

Temp files were not created for MPEG-TS segments options - HLS_TEMP_FILE
flag was never set on AVFormatContext, it is however set on HLSContext object.
In order to fix this issue, proper flags field must be checked. In addition,
renaming code was messed up and apparently was working only for MP4 files.

libavformat/hlsenc.c

@@ -1357,8 +1357,9 @@ static int hls_window(AVFormatContext *s, int last, VariantStream *vs)
     int ret = 0;
     char temp_filename[1024];
     int64_t sequence = FFMAX(hls->start_sequence, vs->sequence - vs->nb_entries);
-    const char *proto = avio_find_protocol_name(s->url);
-    int use_temp_file = proto && !strcmp(proto, "file") && (s->flags & HLS_TEMP_FILE);
+    const char *proto = avio_find_protocol_name(vs->m3u8_name);
+    int is_file_proto = proto && !strcmp(proto, "file");
+    int use_temp_file = is_file_proto && ((hls->flags & HLS_TEMP_FILE) || !(hls->pl_type == PLAYLIST_TYPE_VOD));
     static unsigned warned_non_file;
     char *key_uri = NULL;
     char *iv_string = NULL;
@@ -1381,7 +1382,7 @@ static int hls_window(AVFormatContext *s, int last, VariantStream *vs)
         hls->version = 7;
     }
 
-    if (!use_temp_file && !warned_non_file++)
+    if (!is_file_proto && (hls->flags & HLS_TEMP_FILE) && !warned_non_file++)
         av_log(s, AV_LOG_ERROR, "Cannot use rename on non file protocol, this may lead to races and temporary partial files\n");
 
     set_http_options(s, &options, hls);
@@ -1477,8 +1478,8 @@ static int hls_start(AVFormatContext *s, VariantStream *vs)
     AVFormatContext *oc = vs->avf;
     AVFormatContext *vtt_oc = vs->vtt_avf;
     AVDictionary *options = NULL;
-    const char *proto = avio_find_protocol_name(s->url);
-    int use_temp_file = proto && !strcmp(proto, "file") && (s->flags & HLS_TEMP_FILE);
+    const char *proto = NULL;
+    int use_temp_file = 0;
     char *filename, iv_string[KEYSIZE*2 + 1];
     int err = 0;
 
@@ -1574,6 +1575,9 @@ static int hls_start(AVFormatContext *s, VariantStream *vs)
 
     set_http_options(s, &options, c);
 
+    proto = avio_find_protocol_name(oc->url);
+    use_temp_file = proto && !strcmp(proto, "file") && (c->flags & HLS_TEMP_FILE);
+
     if (use_temp_file) {
         char *new_name = av_asprintf("%s.tmp", oc->url);
         if (!new_name)
@@ -2136,8 +2140,8 @@ static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
     int ret = 0, can_split = 1, i, j;
     int stream_index = 0;
     int range_length = 0;
-    const char *proto = avio_find_protocol_name(s->url);
-    int use_temp_file = proto && !strcmp(proto, "file") && (s->flags & HLS_TEMP_FILE);
+    const char *proto = NULL;
+    int use_temp_file = 0;
     uint8_t *buffer = NULL;
     VariantStream *vs = NULL;
     AVDictionary *options = NULL;
@@ -2248,19 +2252,22 @@ static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
             }
         }
 
+        if (oc->url[0]) {
+            proto = avio_find_protocol_name(oc->url);
+            use_temp_file = proto && !strcmp(proto, "file") && (hls->flags & HLS_TEMP_FILE);
+        }
+
         // look to rename the asset name
-        if (use_temp_file && oc->url[0]) {
+        if (use_temp_file) {
             if (!(hls->flags & HLS_SINGLE_FILE) || (hls->max_seg_size <= 0))
-                if ((vs->avf->oformat->priv_class && vs->avf->priv_data) && hls->segment_type != SEGMENT_TYPE_FMP4) {
+                if ((vs->avf->oformat->priv_class && vs->avf->priv_data) && hls->segment_type != SEGMENT_TYPE_FMP4)
                     av_opt_set(vs->avf->priv_data, "mpegts_flags", "resend_headers", 0);
-                }
         }
 
         if (hls->segment_type == SEGMENT_TYPE_FMP4) {
             if (hls->flags & HLS_SINGLE_FILE) {
                 ret = flush_dynbuf(vs, &range_length);
                 if (ret < 0) {
-                    av_free(old_filename);
                     return ret;
                 }
                 vs->size = range_length;
@@ -2278,20 +2285,13 @@ static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
                     return ret;
                 }
                 ff_format_io_close(s, &vs->out);
-
-                // rename that segment from .tmp to the real one
-                if (use_temp_file && oc->url[0]) {
-                    hls_rename_temp_file(s, oc);
-                    av_free(old_filename);
-                    old_filename = av_strdup(vs->avf->url);
-
-                    if (!old_filename) {
-                        return AVERROR(ENOMEM);
-                    }
-                }
             }
         }
 
+        if (use_temp_file && !(hls->flags & HLS_SINGLE_FILE)) {
+            hls_rename_temp_file(s, oc);
+        }
+
         old_filename = av_strdup(vs->avf->url);
         if (!old_filename) {
             return AVERROR(ENOMEM);
@@ -2360,8 +2360,8 @@ static int hls_write_trailer(struct AVFormatContext *s)
     AVFormatContext *oc = NULL;
     AVFormatContext *vtt_oc = NULL;
     char *old_filename = NULL;
-    const char *proto = avio_find_protocol_name(s->url);
-    int use_temp_file = proto && !strcmp(proto, "file") && (s->flags & HLS_TEMP_FILE);
+    const char *proto = NULL;
+    int use_temp_file = 0;
     int i;
     int ret = 0;
     VariantStream *vs = NULL;
@@ -2372,6 +2372,7 @@ static int hls_write_trailer(struct AVFormatContext *s)
         oc = vs->avf;
         vtt_oc = vs->vtt_avf;
         old_filename = av_strdup(vs->avf->url);
+        use_temp_file = 0;
 
         if (!old_filename) {
             return AVERROR(ENOMEM);
@@ -2415,15 +2416,20 @@ static int hls_write_trailer(struct AVFormatContext *s)
 
 failed:
         av_write_trailer(oc);
+
+        if (oc->url[0]) {
+            proto = avio_find_protocol_name(oc->url);
+            use_temp_file = proto && !strcmp(proto, "file") && (hls->flags & HLS_TEMP_FILE);
+        }
+
         if (oc->pb) {
             if (hls->segment_type != SEGMENT_TYPE_FMP4) {
                 vs->size = avio_tell(vs->avf->pb) - vs->start_pos;
-            }
-            if (hls->segment_type != SEGMENT_TYPE_FMP4)
                 ff_format_io_close(s, &oc->pb);
+            }
 
             // rename that segment from .tmp to the real one
-            if (use_temp_file && oc->url[0] && !(hls->flags & HLS_SINGLE_FILE)) {
+            if (use_temp_file && !(hls->flags & HLS_SINGLE_FILE)) {
                 hls_rename_temp_file(s, oc);
                 av_free(old_filename);
                 old_filename = av_strdup(vs->avf->url);