talloc: define TALLOC_CTX

[ccan] / ccan / talloc / talloc.h

diff --git a/ccan/talloc/talloc.h b/ccan/talloc/talloc.h
index 54790055ea8bf1c56f3452585596b744fd03c5f7..58b406e54b8002b47fce9305725b07491868174e 100644 (file)
--- a/ccan/talloc/talloc.h
+++ b/ccan/talloc/talloc.h
@@ -78,6 +78,29 @@
  */
 #define talloc(ctx, type) (type *)talloc_named_const(ctx, sizeof(type), #type)
 
+/**
+ * TALLOC_CTX - indicate that a pointer is used as a talloc parent.
+ *
+ * As talloc is a hierarchial memory allocator, every talloc chunk is a
+ * potential parent to other talloc chunks. So defining a separate type for a
+ * talloc chunk is not strictly necessary. TALLOC_CTX is defined nevertheless,
+ * as it provides an indicator for function arguments.
+ *
+ * Example:
+ *     struct foo {
+ *             int val;
+ *     };
+ *
+ *     static struct foo *foo_new(TALLOC_CTX *mem_ctx)
+ *     {
+ *             struct foo *foo = talloc(mem_ctx, struct foo);
+ *             if (foo)
+ *                     foo->val = 0;
+ *     return foo;
+ *     }
+ */
+typedef void TALLOC_CTX;
+
 /**
  * talloc_set - allocate dynamic memory for a type, into a pointer
  * @ptr: pointer to the pointer to assign.
@@ -572,7 +595,7 @@ char *talloc_asprintf(const void *t, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3)
  *
  *    talloc_set_name_const(ptr, ptr)
  */
-char *talloc_append_string(char *orig, const char *append);
+char *WARN_UNUSED_RESULT talloc_append_string(char *orig, const char *append);
 
 /**
  * talloc_asprintf_append - sprintf onto the end of a talloc buffer.
@@ -586,7 +609,8 @@ char *talloc_append_string(char *orig, const char *append);
  * equivalent to:
  *   talloc_set_name_const(ptr, ptr)
  */
-char *talloc_asprintf_append(char *s, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3);
+char *WARN_UNUSED_RESULT talloc_asprintf_append(char *s, const char *fmt, ...)
+       PRINTF_ATTRIBUTE(2,3);
 
 /**
  * talloc_vasprintf - vsprintf into a talloc buffer.
@@ -613,7 +637,8 @@ char *talloc_vasprintf(const void *t, const char *fmt, va_list ap) PRINTF_ATTRIB
  * The talloc_vasprintf_append() function is equivalent to
  * talloc_asprintf_append(), except it takes a va_list.
  */
-char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
+char *WARN_UNUSED_RESULT talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
+       PRINTF_ATTRIBUTE(2,0);
 
 /**
  * talloc_set_type - force the name of a pointer to a particular type
@@ -962,7 +987,7 @@ void _talloc_set_destructor(const void *ptr, int (*destructor)(void *));
 size_t talloc_reference_count(const void *ptr);
 void *_talloc_reference(const void *context, const void *ptr);
 
-void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name);
+void *WARN_UNUSED_RESULT _talloc_realloc(const void *context, void *ptr, size_t size, const char *name);
 void *talloc_parent(const void *ptr);
 const char *talloc_parent_name(const void *ptr);
 void *_talloc_steal(const void *new_ctx, const void *ptr);
@@ -971,7 +996,7 @@ void *_talloc_zero(const void *ctx, size_t size, const char *name);
 void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name);
 void *_talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name);
 void *_talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name);
-void *_talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name);
+void *WARN_UNUSED_RESULT _talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name);
 void *talloc_realloc_fn(const void *context, void *ptr, size_t size);
 void talloc_show_parents(const void *context, FILE *file);
 int talloc_is_parent(const void *context, const void *ptr);