[FFmpeg-devel] [PATCH v2 6/9] avformat/http: Add options to set the max number of connection retries

[Martin Storsjö]

On Mon, 22 Apr 2024, Derek Buitenhuis wrote:

> Not every use case benefits from setting retries in terms of the backoff.
>
> Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
> ---
> libavformat/http.c    | 12 +++++++++---
> libavformat/version.h |  2 +-
> 2 files changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/libavformat/http.c b/libavformat/http.c
> index 6927fea2fb..06bd3e340e 100644
> --- a/libavformat/http.c
> +++ b/libavformat/http.c
> @@ -140,6 +140,7 @@ typedef struct HTTPContext {
>     uint64_t filesize_from_content_range;
>     int respect_retry_after;
>     unsigned int retry_after;
> +    int reconnect_max_retries;
> } HTTPContext;
>
> #define OFFSET(x) offsetof(HTTPContext, x)
> @@ -178,6 +179,7 @@ static const AVOption options[] = {
>     { "reconnect_on_http_error", "list of http status codes to reconnect on", OFFSET(reconnect_on_http_error), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, D },
>     { "reconnect_streamed", "auto reconnect streamed / non seekable streams", OFFSET(reconnect_streamed), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, D },
>     { "reconnect_delay_max", "max reconnect delay in seconds after which to give up", OFFSET(reconnect_delay_max), AV_OPT_TYPE_INT, { .i64 = 120 }, 0, UINT_MAX/1000/1000, D },
> +    { "reconnect_max_retries", "the max number of times to retry a connection", OFFSET(reconnect_max_retries), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, D },
>     { "respect_retry_after", "respect the Retry-After header when retrying connections", OFFSET(respect_retry_after), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, D },
>     { "listen", "listen on HTTP", OFFSET(listen), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, D | E },
>     { "resource", "The resource requested by a client", OFFSET(resource), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
> @@ -359,7 +361,7 @@ static int http_open_cnx(URLContext *h, AVDictionary **options)
> {
>     HTTPAuthType cur_auth_type, cur_proxy_auth_type;
>     HTTPContext *s = h->priv_data;
> -    int ret, auth_attempts = 0, redirects = 0;
> +    int ret, conn_attempts = 1, auth_attempts = 0, redirects = 0;
>     int reconnect_delay = 0;
>     uint64_t off;
>     char *cached;
> @@ -386,7 +388,8 @@ redo:
>     ret = http_open_cnx_internal(h, options);
>     if (ret < 0) {
>         if (!http_should_reconnect(s, ret) ||
> -            reconnect_delay > s->reconnect_delay_max)
> +            reconnect_delay > s->reconnect_delay_max ||
> +            (s->reconnect_max_retries >= 0 && conn_attempts > s->reconnect_max_retries))
>             goto fail;
>
>         if (s->respect_retry_after && s->retry_after > 0) {
> @@ -401,6 +404,7 @@ redo:
>         if (ret != AVERROR(ETIMEDOUT))
>             goto fail;
>         reconnect_delay = 1 + 2 * reconnect_delay;
> +        conn_attempts++;
>
>         /* restore the offset (http_connect resets it) */
>         s->off = off;
> @@ -1706,6 +1710,7 @@ static int http_read_stream(URLContext *h, uint8_t *buf, int size)
>     int err, read_ret;
>     int64_t seek_ret;
>     int reconnect_delay = 0;
> +    int conn_attempt = 1;

Minor inconsistency; the corresponding variable in the other function was 
called conn_attempts, as a plural.

// Martin