| 1 | #ifndef BABELTRACE_CTF_IR_REF_H |
| 2 | #define BABELTRACE_CTF_IR_REF_H |
| 3 | |
| 4 | /* |
| 5 | * BabelTrace - CTF IR: common reference counting |
| 6 | * |
| 7 | * Copyright (c) 2015 EfficiOS Inc. and Linux Foundation |
| 8 | * Copyright (c) 2015 Philippe Proulx <pproulx@efficios.com> |
| 9 | * |
| 10 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 11 | * of this software and associated documentation files (the "Software"), to deal |
| 12 | * in the Software without restriction, including without limitation the rights |
| 13 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 14 | * copies of the Software, and to permit persons to whom the Software is |
| 15 | * furnished to do so, subject to the following conditions: |
| 16 | * |
| 17 | * The above copyright notice and this permission notice shall be included in |
| 18 | * all copies or substantial portions of the Software. |
| 19 | * |
| 20 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 21 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 23 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 24 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 25 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 26 | * SOFTWARE. |
| 27 | */ |
| 28 | |
| 29 | #include <assert.h> |
| 30 | #include <babeltrace/ref-internal.h> |
| 31 | #include <babeltrace/ctf-ir/common-internal.h> |
| 32 | |
| 33 | /* |
| 34 | * BT_CTF_PUT: calls bt_ctf_put() with a variable, then sets this |
| 35 | * variable to NULL. |
| 36 | * |
| 37 | * A common action with CTF IR objects is to create or get one, do |
| 38 | * something with it, and then put it. To avoid putting it a second time |
| 39 | * later (if an error occurs, for example), the variable is often reset |
| 40 | * to NULL after putting the object it points to. Since this is so |
| 41 | * common, you can use the BT_CTF_PUT() macro, which does just that. |
| 42 | * |
| 43 | * It is safe to call this function with a NULL object. |
| 44 | * |
| 45 | * @param obj CTF IR object. |
| 46 | */ |
| 47 | #define BT_CTF_PUT(_obj) \ |
| 48 | do { \ |
| 49 | bt_ctf_put(_obj); \ |
| 50 | (_obj) = NULL; \ |
| 51 | } while (0) |
| 52 | |
| 53 | /* |
| 54 | * BT_CTF_MOVE: moves the ownership of a CTF object, setting the old |
| 55 | * owner to NULL. |
| 56 | * |
| 57 | * This macro sets the variable _dst to the value of the variable _src, |
| 58 | * then sets _src to NULL, effectively moving the ownership of a CTF |
| 59 | * object from one variable to the other. |
| 60 | * |
| 61 | * @param obj CTF IR object. |
| 62 | */ |
| 63 | #define BT_CTF_MOVE(_dst, _src) \ |
| 64 | do { \ |
| 65 | (_dst) = (_src); \ |
| 66 | (_src) = NULL; \ |
| 67 | } while (0) |
| 68 | |
| 69 | /* |
| 70 | * bt_ctf_get: increments the reference count of a CTF IR object. |
| 71 | * |
| 72 | * The same number of bt_ctf_get() and bt_ctf_put() (plus one extra |
| 73 | * bt_ctf_put() to release the initial reference done at creation) have |
| 74 | * to be done to destroy a CTF IR object. |
| 75 | * |
| 76 | * It is safe to call this function with a NULL object. |
| 77 | * |
| 78 | * @param obj CTF IR object. |
| 79 | */ |
| 80 | static inline |
| 81 | void bt_ctf_get(void *obj) |
| 82 | { |
| 83 | if (obj) { |
| 84 | struct bt_ctf_base *base = obj; |
| 85 | |
| 86 | bt_ref_get(&base->ref_count); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * bt_ctf_put: decrements the reference count of a CTF IR object. |
| 92 | * |
| 93 | * The same number of bt_ctf_get() and bt_ctf_put() (plus one extra |
| 94 | * bt_ctf_put() to release the initial reference done at creation) have |
| 95 | * to be done to destroy a CTF IR object. |
| 96 | * |
| 97 | * When the object's reference count is decremented to 0 by a call to |
| 98 | * bt_ctf_put(), the object is freed. |
| 99 | * |
| 100 | * It is safe to call this function with a NULL object. |
| 101 | * |
| 102 | * @param obj CTF IR object. |
| 103 | */ |
| 104 | static inline |
| 105 | void bt_ctf_put(void *obj) |
| 106 | { |
| 107 | if (obj) { |
| 108 | struct bt_ctf_base *base = obj; |
| 109 | |
| 110 | bt_ref_put(&base->ref_count); |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | #endif /* BABELTRACE_CTF_IR_REF_H */ |