vtgl

Commit: 4421c6c6fbfa37fb60c7d1b348c4bc8a210bbca2
Parent: cbf03635c7e1f678da8d1a3becb06b2d7a273929
Author: Randy Palamar
Date:   Thu, 23 Jan 2025 08:21:00 -0700

test: better terminal memory cleanup

* don't actually unmap the terminal backing; instead mark it as
  inaccessible and tell kernel that it can be freed. This way we
  can catch any bugs related to global state or accidental reuse

* do unmap the ringbuffers since they can not be marked as free
  since they need to be map as shared regions.

Diffstat:
M
platform_linux_aarch64.c
 | 
1
+
M
platform_linux_amd64.c
 | 
1
+
M
platform_linux_common.c
 | 
11
++++++++++-
M
tests/test.c
 | 
11
++++++++++-

4 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/platform_linux_aarch64.c b/platform_linux_aarch64.c
@@ -30,6 +30,7 @@
 #define SYS_clone             220
 #define SYS_execve            221
 #define SYS_mmap              222
+#define SYS_mprotect          226
 #define SYS_madvise           233
 #define SYS_wait4             260
 #define SYS_memfd_create      279
diff --git a/platform_linux_amd64.c b/platform_linux_amd64.c
@@ -12,6 +12,7 @@
 #define SYS_write               1
 #define SYS_close               3
 #define SYS_mmap                9
+#define SYS_mprotect           10
 #define SYS_munmap             11
 #define SYS_ioctl              16
 #define SYS_pwrite64           18
diff --git a/platform_linux_common.c b/platform_linux_common.c
@@ -5,6 +5,7 @@
 
 #define PR_SET_NAME 15
 
+#define PROT_NONE   0x00
 #define PROT_READ   0x01
 #define PROT_RW     0x03
 
@@ -15,6 +16,7 @@
 #define MAP_FIXED   0x10
 #define MAP_ANON    0x20
 
+#define MADV_FREE      8
 #define MADV_HUGEPAGE 14
 
 #define O_RDONLY    0x00000
@@ -240,7 +242,14 @@ os_block_alloc(size requested_size)
 static void
 os_release_memory_block(MemoryBlock memory)
 {
-	syscall2(SYS_munmap, (iptr)memory.memory, memory.size);
+	syscall3(SYS_madvise,  (iptr)memory.memory, memory.size, MADV_FREE);
+	syscall3(SYS_mprotect, (iptr)memory.memory, memory.size, PROT_NONE);
+}
+
+static void
+os_release_ring_buffer(RingBuf *rb)
+{
+	syscall2(SYS_munmap, (iptr)(rb->buf - rb->cap), rb->cap * 3);
 }
 
 static f64
diff --git a/tests/test.c b/tests/test.c
@@ -430,6 +430,15 @@ place_term_into_memory(MemoryBlock memory, i32 rows, i32 columns)
 	return t;
 }
 
+static void
+release_term_memory(MemoryBlock backing)
+{
+	Term *t = backing.memory;
+	os_release_ring_buffer(&t->views[0].log);
+	os_release_ring_buffer(&t->views[1].log);
+	os_release_memory_block(backing);
+}
+
 int
 main(void)
 {
@@ -461,7 +470,7 @@ main(void)
 		case SUCCESS:     stream_push_s8(&log, success_string);                  break;
 		case UNSUPPORTED: stream_push_s8(&log, unsupported_string);              break;
 		}
-		os_release_memory_block(term_backing);
+		release_term_memory(term_backing);
 	}
 	stream_push_s8(&log, s8("FINISHED: ["));
 	stream_push_u64(&log, ARRAY_COUNT(tests) - failure_count);