Fix incorrect description of m in TOC index.

Author: Rot127

README.md

@@ -65,8 +65,8 @@ the BAP-frames repository.
 |    ...     | ...          | ... | |
 |    T-0x10  | uint64_t     | sizeof(frame_n-1) | |
 |    T-0x8   | type(frame_n-1) | frame_n-1 | |
-|    T+0     | uint64_t     | m = number of TOC entries | TOC index begin |
+|    T+0     | uint64_t     | m = number of frames per TOC entry | TOC index begin |
 |    T+0x8   | uint64_t     | offset toc_entry(0) | |
 |    T+0x10  | uint64_t     | offset toc_entry(1) | |
 |    ...     | ...          | ... | |
-|    T+0x8+(0x8*m)   | uint64_t     | offset toc_entry(m-1) | |
+|    T+0x8+(0x8*ceil(n/m))   | uint64_t     | offset toc_entry(ceil(n/m)) | |

contrib/plugins/bap-tracing/tracing.c

@@ -221,17 +221,11 @@ static void plugin_exit(qemu_plugin_id_t id, void *udata) {
 
   // Write the TOC index
   SEEK(toc_index_offset);
-  uint64_t m = state.toc_entries_offsets->len;
-  WRITE(m);
-
-  for (size_t i = 0; i < m - 1; ++i) {
-    // All except the last address in state.toc_entries_offsets
-    // point to an entry. The last one points to nothing, because
-    // we first push the offset and then push the frames later
-    // when the buffer is full.
-    // When we dumped the last frames above it lastly
-    // pushed an additional offset.
-    // This one we skip here with m - 1.
+  WRITE(frames_per_toc_entry);
+  size_t add = state.total_num_frames % frames_per_toc_entry != 0 ? 1 : 0;
+  size_t entries = ((state.total_num_frames) / frames_per_toc_entry) + add;
+
+  for (size_t i = 0; i < entries; ++i) {
     uint64_t toc_entry_off =
         g_array_index(state.toc_entries_offsets, uint64_t, i);
     WRITE(toc_entry_off);