Commit | Line | Data |
---|---|---|
5966417e | 1 | /* |
ab5be9fa | 2 | * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
5966417e | 3 | * |
ab5be9fa | 4 | * SPDX-License-Identifier: LGPL-2.1-only |
5966417e | 5 | * |
5966417e JG |
6 | */ |
7 | ||
c9e313bc | 8 | #include <common/buffer-view.hpp> |
28ab034a | 9 | #include <common/dynamic-buffer.hpp> |
c9e313bc | 10 | #include <common/utils.hpp> |
5966417e | 11 | |
df94ef0f JG |
12 | /* |
13 | * Round to (upper) power of two, val is returned if it already is a power of | |
14 | * two. | |
15 | */ | |
28ab034a | 16 | static size_t round_to_power_of_2(size_t val) |
5966417e | 17 | { |
5966417e | 18 | size_t rounded; |
12aacdf6 | 19 | const int order = utils_get_count_order_u64(val); |
5966417e | 20 | |
a0377dfe | 21 | LTTNG_ASSERT(order >= 0); |
5966417e | 22 | rounded = (1ULL << order); |
a0377dfe | 23 | LTTNG_ASSERT(rounded >= val); |
5966417e JG |
24 | |
25 | return rounded; | |
26 | } | |
27 | ||
28 | void lttng_dynamic_buffer_init(struct lttng_dynamic_buffer *buffer) | |
29 | { | |
a0377dfe | 30 | LTTNG_ASSERT(buffer); |
5966417e JG |
31 | memset(buffer, 0, sizeof(*buffer)); |
32 | } | |
33 | ||
28ab034a | 34 | int lttng_dynamic_buffer_append(struct lttng_dynamic_buffer *buffer, const void *buf, size_t len) |
5966417e JG |
35 | { |
36 | int ret = 0; | |
37 | ||
38 | if (!buffer || (!buf && len)) { | |
39 | ret = -1; | |
40 | goto end; | |
41 | } | |
42 | ||
43 | if (len == 0) { | |
44 | /* Not an error, no-op. */ | |
45 | goto end; | |
46 | } | |
47 | ||
a0377dfe | 48 | LTTNG_ASSERT(buffer->_capacity >= buffer->size); |
63557623 | 49 | if (buffer->_capacity < (len + buffer->size)) { |
28ab034a JG |
50 | ret = lttng_dynamic_buffer_set_capacity( |
51 | buffer, buffer->_capacity + (len - (buffer->_capacity - buffer->size))); | |
5966417e JG |
52 | if (ret) { |
53 | goto end; | |
54 | } | |
55 | } | |
56 | ||
57 | memcpy(buffer->data + buffer->size, buf, len); | |
58 | buffer->size += len; | |
59 | end: | |
60 | return ret; | |
61 | } | |
62 | ||
63 | int lttng_dynamic_buffer_append_buffer(struct lttng_dynamic_buffer *dst_buffer, | |
28ab034a | 64 | const struct lttng_dynamic_buffer *src_buffer) |
5966417e JG |
65 | { |
66 | int ret; | |
67 | ||
68 | if (!dst_buffer || !src_buffer) { | |
69 | ret = -1; | |
70 | goto end; | |
71 | } | |
72 | ||
28ab034a | 73 | ret = lttng_dynamic_buffer_append(dst_buffer, src_buffer->data, src_buffer->size); |
5966417e JG |
74 | end: |
75 | return ret; | |
76 | } | |
77 | ||
fbd55aae | 78 | int lttng_dynamic_buffer_append_view(struct lttng_dynamic_buffer *buffer, |
28ab034a | 79 | const struct lttng_buffer_view *src) |
fbd55aae JG |
80 | { |
81 | int ret; | |
82 | ||
83 | if (!buffer || !src) { | |
84 | ret = -1; | |
85 | goto end; | |
86 | } | |
87 | ||
28ab034a | 88 | ret = lttng_dynamic_buffer_append(buffer, src->data, src->size); |
fbd55aae JG |
89 | end: |
90 | return ret; | |
91 | } | |
92 | ||
28ab034a | 93 | int lttng_dynamic_buffer_set_size(struct lttng_dynamic_buffer *buffer, size_t new_size) |
5966417e JG |
94 | { |
95 | int ret = 0; | |
96 | ||
97 | if (!buffer) { | |
98 | goto end; | |
99 | } | |
100 | ||
101 | if (new_size == buffer->size) { | |
102 | goto end; | |
103 | } | |
104 | ||
63557623 | 105 | if (new_size > buffer->_capacity) { |
5966417e JG |
106 | ret = lttng_dynamic_buffer_set_capacity(buffer, new_size); |
107 | if (ret) { | |
108 | goto end; | |
109 | } | |
1c6def05 | 110 | |
6ee96b4d | 111 | memset(buffer->data + buffer->size, 0, new_size - buffer->size); |
5966417e JG |
112 | } else if (new_size > buffer->size) { |
113 | memset(buffer->data + buffer->size, 0, new_size - buffer->size); | |
114 | } else { | |
115 | /* | |
116 | * Shrinking size. There is no need to zero-out the newly | |
117 | * released memory as it will either be: | |
118 | * - overwritten by lttng_dynamic_buffer_append, | |
119 | * - expanded later, which will zero-out the memory | |
120 | * | |
121 | * Users of external APIs are encouraged to set the buffer's | |
122 | * size _before_ making such calls. | |
123 | */ | |
124 | } | |
12aacdf6 | 125 | |
5966417e JG |
126 | buffer->size = new_size; |
127 | end: | |
128 | return ret; | |
129 | } | |
130 | ||
28ab034a | 131 | int lttng_dynamic_buffer_set_capacity(struct lttng_dynamic_buffer *buffer, size_t demanded_capacity) |
5966417e JG |
132 | { |
133 | int ret = 0; | |
fc804d0f | 134 | void *new_buf; |
07c4863f | 135 | const size_t new_capacity = demanded_capacity ? round_to_power_of_2(demanded_capacity) : 0; |
5966417e | 136 | |
fc804d0f JG |
137 | if (!buffer || demanded_capacity < buffer->size) { |
138 | /* | |
139 | * Shrinking a buffer's size by changing its capacity is | |
140 | * unsupported. | |
141 | */ | |
5966417e JG |
142 | ret = -1; |
143 | goto end; | |
144 | } | |
145 | ||
63557623 | 146 | if (new_capacity == buffer->_capacity) { |
5966417e JG |
147 | goto end; |
148 | } | |
149 | ||
fc804d0f JG |
150 | /* Memory is initialized by the size increases. */ |
151 | new_buf = realloc(buffer->data, new_capacity); | |
152 | if (!new_buf) { | |
153 | ret = -1; | |
154 | goto end; | |
5966417e | 155 | } |
12aacdf6 | 156 | |
a6bc4ca9 | 157 | buffer->data = (char *) new_buf; |
63557623 | 158 | buffer->_capacity = new_capacity; |
5966417e JG |
159 | end: |
160 | return ret; | |
161 | } | |
162 | ||
163 | /* Release any memory used by the dynamic buffer. */ | |
164 | void lttng_dynamic_buffer_reset(struct lttng_dynamic_buffer *buffer) | |
165 | { | |
166 | if (!buffer) { | |
167 | return; | |
168 | } | |
12aacdf6 | 169 | |
5966417e | 170 | buffer->size = 0; |
63557623 | 171 | buffer->_capacity = 0; |
5966417e | 172 | free(buffer->data); |
cd9adb8b | 173 | buffer->data = nullptr; |
5966417e | 174 | } |
201bd415 | 175 | |
28ab034a | 176 | size_t lttng_dynamic_buffer_get_capacity_left(struct lttng_dynamic_buffer *buffer) |
201bd415 JG |
177 | { |
178 | if (!buffer) { | |
179 | return 0; | |
180 | } | |
12aacdf6 | 181 | |
201bd415 JG |
182 | return buffer->_capacity - buffer->size; |
183 | } |