Changeset f571ca49 in mainline for kernel/generic/src/cap/cap.c

Timestamp:

2017-11-24T19:00:00Z (6 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

ac307b2

Parents:

503ffce

Message:

Add CAP_NIL

Sometimes it is useful to have a capability analogy of NULL.

File:

• kernel/generic/src/cap/cap.c (modified) (5 diffs)

kernel/generic/src/cap/cap.c

@@ -73 +73 @@
 
 #include <cap/cap.h>
+#include <abi/cap.h>
 #include <proc/task.h>
 #include <synch/mutex.h>
@@ -81 +82 @@
 #include <stdint.h>
 
-#define MAX_CAPS        INT_MAX
+#define CAPS_START      (CAP_NIL + 1)
+#define CAPS_SIZE       (INT_MAX - CAPS_START)
+#define CAPS_LAST       (CAPS_SIZE - 1)
 
 static slab_cache_t *cap_slab;
@@ -129 +132 @@
         if (!task->cap_info->handles)
                 goto error_handles;
-        if (!ra_span_add(task->cap_info->handles, 0, MAX_CAPS))
+        if (!ra_span_add(task->cap_info->handles, CAPS_START, CAPS_SIZE))
                 goto error_span;
         if (!hash_table_create(&task->cap_info->caps, 0, 0, &caps_ops))
@@ -220 +223 @@
         assert(mutex_locked(&task->cap_info->lock));
 
-        if ((handle < 0) || (handle >= MAX_CAPS))
+        if ((handle < CAPS_START) || (handle > CAPS_LAST))
                 return NULL;
         ht_link_t *link = hash_table_find(&task->cap_info->caps, &handle);
@@ -357 +360 @@
 void cap_free(task_t *task, cap_handle_t handle)
 {
-        assert(handle >= 0);
-        assert(handle < MAX_CAPS);
+        assert(handle >= CAPS_START);
+        assert(handle <= CAPS_LAST);
 
         mutex_lock(&task->cap_info->lock);