Rodger Combs (12019-09-21): > This can be used to resolve particular hosts offline without affecting > HTTP headers, TLS SNI, or cross-domain redirects. It works similarly to > curl's --resolve option, but without port-specific handling. > --- > libavformat/tcp.c | 27 +++++++++++++++++++++++++++ > libavformat/version.h | 2 +- > 2 files changed, 28 insertions(+), 1 deletion(-)
I personally do not like it much. Here are my objections:
- This could apply to any networking program, it should be in the libc.
- If it is done inside FFmpeg, it should work for all name resolution,
including UDP.
- The syntax you chose makes it awkward for IPv6 because of multiple
colons.
- You neglected the documentation.
>
> diff --git a/libavformat/tcp.c b/libavformat/tcp.c
> index 2198e0f00e..e4c439ee56 100644
> --- a/libavformat/tcp.c
> +++ b/libavformat/tcp.c
> @@ -45,6 +45,7 @@ typedef struct TCPContext {
> #if !HAVE_WINSOCK2_H
> int tcp_mss;
> #endif /* !HAVE_WINSOCK2_H */
> + char *resolve_hosts;
> } TCPContext;
>
> #define OFFSET(x) offsetof(TCPContext, x)
> @@ -60,6 +61,7 @@ static const AVOption options[] = {
> #if !HAVE_WINSOCK2_H
> { "tcp_mss", "Maximum segment size for outgoing TCP packets",
> OFFSET(tcp_mss), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX,
> .flags = D|E },
> #endif /* !HAVE_WINSOCK2_H */
> + { "resolve_hosts", "Comma-separated host resolutions, in the form
> host:ip", OFFSET(resolve_hosts), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0,
> .flags = D|E },
> { NULL }
> };
>
> @@ -99,6 +101,27 @@ static void customize_fd(void *ctx, int fd)
> #endif /* !HAVE_WINSOCK2_H */
> }
>
> +static int lookup_host(URLContext *h, char *hostname, size_t hostname_size)
> +{
> + TCPContext *s = h->priv_data;
> + if (hostname[0]) {
> + size_t hostlen = strlen(hostname);
> + for (const char *addr = s->resolve_hosts; addr; addr = strchr(addr,
> ','), addr && addr++) {
> + if (!strncmp(addr, hostname, hostlen) && addr[hostlen] == ':') {
> + addr += hostlen + 1;
> + const char *end = strchr(addr, ',');
> + size_t len = end ? end - addr : strlen(addr);
> + if (len >= hostname_size - 1)
> + return AVERROR(ENOMEM);
> + memcpy(hostname, addr, len);
> + hostname[len] = 0;
> + return 0;
> + }
> + }
I find the duplicated comma search awkward. I find this code structure
easier to understand:
while (1) {
end = strchr(addr, ',');
len = end ? end - addr : strlen(addr);
/* or len = strcspn(addr, ","); */
/* process with len */
addr += len;
if (*addr)
break;
addr++;
}
> + }
> + return 0;
> +}
> +
> /* return non zero if error */
> static int tcp_open(URLContext *h, const char *uri, int flags)
> {
> @@ -120,6 +143,10 @@ static int tcp_open(URLContext *h, const char *uri, int
> flags)
> av_log(h, AV_LOG_ERROR, "Port missing in uri\n");
> return AVERROR(EINVAL);
> }
> +
> + if ((ret = lookup_host(h, hostname, sizeof(hostname))) < 0)
> + return ret;
> +
> p = strchr(uri, '?');
> if (p) {
> if (av_find_info_tag(buf, sizeof(buf), "listen", p)) {
> diff --git a/libavformat/version.h b/libavformat/version.h
> index 2eb14659d0..d1dbb1e2d1 100644
> --- a/libavformat/version.h
> +++ b/libavformat/version.h
> @@ -33,7 +33,7 @@
> // Also please add any ticket numbers that you believe might be affected here
> #define LIBAVFORMAT_VERSION_MAJOR 58
> #define LIBAVFORMAT_VERSION_MINOR 32
> -#define LIBAVFORMAT_VERSION_MICRO 105
> +#define LIBAVFORMAT_VERSION_MICRO 106
>
> #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
> LIBAVFORMAT_VERSION_MINOR, \
Regards,
--
Nicolas George
signature.asc
Description: PGP signature
_______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
