From 51e901c191737af0e207749cb53b49a5daf57b37 Mon Sep 17 00:00:00 2001
From: Lynne <dev@lynne.ee>
Date: Sat, 29 Jun 2024 06:49:45 +0200
Subject: [PATCH] Add padding to option structures to avoid ABI breakage

---
 libavtransport/include/avtransport/avtransport.h |  3 +++
 libavtransport/include/avtransport/connection.h  | 15 +++++++++++++++
 libavtransport/include/avtransport/receive.h     | 13 ++++++++++++-
 libavtransport/include/avtransport/send.h        |  3 +++
 libavtransport/include/avtransport/stream.h      |  6 ++++++
 5 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/libavtransport/include/avtransport/avtransport.h b/libavtransport/include/avtransport/avtransport.h
index b958656..3afd34b 100644
--- a/libavtransport/include/avtransport/avtransport.h
+++ b/libavtransport/include/avtransport/avtransport.h
@@ -54,6 +54,9 @@ typedef struct AVTContextOptions {
 
     char producer_name[16];   /* Name of the project linking to libavtransport */
     uint16_t producer_ver[3]; /* Major, minor, micro version */
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[4096 - 16*1 - 3*2 - 0*4 - 2*8];
 } AVTContextOptions;
 
 /* Allocate an AVTransport context with the given context options. */
diff --git a/libavtransport/include/avtransport/connection.h b/libavtransport/include/avtransport/connection.h
index 57c5697..1dafe69 100644
--- a/libavtransport/include/avtransport/connection.h
+++ b/libavtransport/include/avtransport/connection.h
@@ -199,6 +199,9 @@ typedef struct AVTConnectionInfo {
             /* Opaque pointer which will be used for the data() callback. */
             void *opaque;
         } pkt;
+
+        /* Padding to allow for future options. */
+        uint8_t padding_u[1024 - 17*1 - 1*2 - 5*4 - 0*8];
     };
 
     /* Input options */
@@ -210,6 +213,9 @@ typedef struct AVTConnectionInfo {
          * automatic (very rarely), higher values increase overhead
          * and decrease potential errors, negative values disables decoding. */
         int ldpc_iterations;
+
+        /* Padding to allow for future options. Must always be set to 0. */
+        uint8_t padding[1024 - 0*1 - 0*2 - 1*4 - 1*8];
     } input_opts;
 
     struct {
@@ -246,11 +252,17 @@ typedef struct AVTConnectionInfo {
          *  - N: In addition, send one every N packets (segmentation is ignored).
          */
         unsigned int session_start_freq;
+
+        /* Padding to allow for future options. Must always be set to 0. */
+        uint8_t padding[1024 - 0*1 - 0*2 - 1*4 - 2*8];
     } output_opts;
 
     /* When greater than 0, enables asynchronous mode.
      * Values greater than 1 are reserved. */
     int async;
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[1024 - 0*1 - 0*2 - 1*4 - 0*8];
 } AVTConnectionInfo;
 
 /**
@@ -357,6 +369,9 @@ typedef struct AVTConnectionStatus {
         /* Total duration of all packets buffered (timebase: 1 nanosecond) */
         int64_t buffer_duration;
     } tx;
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[4096 - 0*1 - 0*2 - 3*4 - 10*8];
 } AVTConnectionStatus;
 
 /**
diff --git a/libavtransport/include/avtransport/receive.h b/libavtransport/include/avtransport/receive.h
index ec318cb..e72e56c 100644
--- a/libavtransport/include/avtransport/receive.h
+++ b/libavtransport/include/avtransport/receive.h
@@ -32,7 +32,18 @@
 #include "utils.h"
 
 typedef struct AVTReceiveOptions {
-    ;
+    /* Setting this flag to 1 enables receival of incomplete packets.
+     * Regions with no data are set to 0.
+     *
+     * NOTE: Data from compressed packets will only be passed if decompression
+     *       (partially) succeeds.
+     * NOTE: raw audio and video packets are always passed, even if incomplete,
+     *       as long as they are uncompressed.
+     */
+    bool accept_incomplete;
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[4096 - 1*1 - 0*2 - 0*4 - 0*8];
 } AVTReceiveOptions;
 
 /* List of callbacks. All are optional. */
diff --git a/libavtransport/include/avtransport/send.h b/libavtransport/include/avtransport/send.h
index 3fbb2e4..45b3715 100644
--- a/libavtransport/include/avtransport/send.h
+++ b/libavtransport/include/avtransport/send.h
@@ -66,6 +66,9 @@ typedef struct AVTSenderOptions {
 
     /* Set to true to enable sending hash packets for all packets with a payload. */
     bool hash;
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[4096 - 1*8 - 0*16 - 3*32 - 0*64];
 } AVTSenderOptions;
 
 /* Open a send context and immediately send/write a stream session packet.
diff --git a/libavtransport/include/avtransport/stream.h b/libavtransport/include/avtransport/stream.h
index b2ae6fe..2a797b0 100644
--- a/libavtransport/include/avtransport/stream.h
+++ b/libavtransport/include/avtransport/stream.h
@@ -70,6 +70,9 @@ typedef struct AVTStream {
 
     /* libavtransport private stream data. Do not touch or use. */
     struct AVTStreamPriv *priv;
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[4096];
 } AVTStream;
 
 typedef struct AVTPacket {
@@ -80,6 +83,9 @@ typedef struct AVTPacket {
     int64_t pts;
     int64_t dts;
     int64_t duration;
+
+    /* Padding to allow for future options. Must always be set to 0. */
+    uint8_t padding[64];
 } AVTPacket;
 
 #endif