| 1 | #ifndef QEMU_FIFO8_H |
| 2 | #define QEMU_FIFO8_H |
| 3 | |
| 4 | |
| 5 | typedef struct { |
| 6 | /* All fields are private */ |
| 7 | uint8_t *data; |
| 8 | uint32_t capacity; |
| 9 | uint32_t head; |
| 10 | uint32_t num; |
| 11 | } Fifo8; |
| 12 | |
| 13 | /** |
| 14 | * fifo8_create: |
| 15 | * @fifo: struct Fifo8 to initialise with new FIFO |
| 16 | * @capacity: capacity of the newly created FIFO |
| 17 | * |
| 18 | * Create a FIFO of the specified capacity. Clients should call fifo8_destroy() |
| 19 | * when finished using the fifo. The FIFO is initially empty. |
| 20 | */ |
| 21 | void fifo8_create(Fifo8 *fifo, uint32_t capacity); |
| 22 | |
| 23 | /** |
| 24 | * fifo8_destroy: |
| 25 | * @fifo: FIFO to cleanup |
| 26 | * |
| 27 | * Cleanup a FIFO created with fifo8_create(). Frees memory created for FIFO |
| 28 | * storage. The FIFO is no longer usable after this has been called. |
| 29 | */ |
| 30 | void fifo8_destroy(Fifo8 *fifo); |
| 31 | |
| 32 | /** |
| 33 | * fifo8_push: |
| 34 | * @fifo: FIFO to push to |
| 35 | * @data: data byte to push |
| 36 | * |
| 37 | * Push a data byte to the FIFO. Behaviour is undefined if the FIFO is full. |
| 38 | * Clients are responsible for checking for fullness using fifo8_is_full(). |
| 39 | */ |
| 40 | void fifo8_push(Fifo8 *fifo, uint8_t data); |
| 41 | |
| 42 | /** |
| 43 | * fifo8_push_all: |
| 44 | * @fifo: FIFO to push to |
| 45 | * @data: data to push |
| 46 | * @num: number of bytes to push |
| 47 | * |
| 48 | * Push a byte array to the FIFO. Behaviour is undefined if the FIFO is full. |
| 49 | * Clients are responsible for checking the space left in the FIFO using |
| 50 | * fifo8_num_free(). |
| 51 | */ |
| 52 | void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num); |
| 53 | |
| 54 | /** |
| 55 | * fifo8_pop: |
| 56 | * @fifo: fifo to pop from |
| 57 | * |
| 58 | * Pop a data byte from the FIFO. Behaviour is undefined if the FIFO is empty. |
| 59 | * Clients are responsible for checking for emptyness using fifo8_is_empty(). |
| 60 | * |
| 61 | * Returns: The popped data byte. |
| 62 | */ |
| 63 | uint8_t fifo8_pop(Fifo8 *fifo); |
| 64 | |
| 65 | /** |
| 66 | * fifo8_peek: |
| 67 | * @fifo: fifo to peek from |
| 68 | * |
| 69 | * Peek the data byte at the current head of the FIFO. Clients are responsible |
| 70 | * for checking for emptyness using fifo8_is_empty(). |
| 71 | * |
| 72 | * Returns: The peeked data byte. |
| 73 | */ |
| 74 | uint8_t fifo8_peek(const Fifo8 *fifo); |
| 75 | |
| 76 | /** |
| 77 | * fifo8_pop_buf: |
| 78 | * @fifo: FIFO to pop from |
| 79 | * @dest: the buffer to write the data into (can be NULL) |
| 80 | * @destlen: size of @dest and maximum number of bytes to pop |
| 81 | * |
| 82 | * Pop a number of elements from the FIFO up to a maximum of @destlen. |
| 83 | * The popped data is copied into the @dest buffer. |
| 84 | * Care is taken when the data wraps around in the ring buffer. |
| 85 | * |
| 86 | * Returns: number of bytes popped. |
| 87 | */ |
| 88 | uint32_t fifo8_pop_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen); |
| 89 | |
| 90 | /** |
| 91 | * fifo8_peek_buf: |
| 92 | * @fifo: FIFO to read from |
| 93 | * @dest: the buffer to write the data into (can be NULL) |
| 94 | * @destlen: size of @dest and maximum number of bytes to peek |
| 95 | * |
| 96 | * Peek a number of elements from the FIFO up to a maximum of @destlen. |
| 97 | * The peeked data is copied into the @dest buffer. |
| 98 | * Care is taken when the data wraps around in the ring buffer. |
| 99 | * |
| 100 | * Returns: number of bytes peeked. |
| 101 | */ |
| 102 | uint32_t fifo8_peek_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen); |
| 103 | |
| 104 | /** |
| 105 | * fifo8_pop_bufptr: |
| 106 | * @fifo: FIFO to pop from |
| 107 | * @max: maximum number of bytes to pop |
| 108 | * @numptr: pointer filled with number of bytes returned (can be NULL) |
| 109 | * |
| 110 | * New code should prefer to use fifo8_pop_buf() instead of fifo8_pop_bufptr(). |
| 111 | * |
| 112 | * Pop a number of elements from the FIFO up to a maximum of @max. The buffer |
| 113 | * containing the popped data is returned. This buffer points directly into |
| 114 | * the internal FIFO backing store and data (without checking for overflow!) |
| 115 | * and is invalidated once any of the fifo8_* APIs are called on the FIFO. |
| 116 | * |
| 117 | * The function may return fewer bytes than requested when the data wraps |
| 118 | * around in the ring buffer; in this case only a contiguous part of the data |
| 119 | * is returned. |
| 120 | * |
| 121 | * The number of valid bytes returned is populated in *@numptr; will always |
| 122 | * return at least 1 byte. max must not be 0 or greater than the number of |
| 123 | * bytes in the FIFO. |
| 124 | * |
| 125 | * Clients are responsible for checking the availability of requested data |
| 126 | * using fifo8_num_used(). |
| 127 | * |
| 128 | * Returns: A pointer to popped data. |
| 129 | */ |
| 130 | const uint8_t *fifo8_pop_bufptr(Fifo8 *fifo, uint32_t max, uint32_t *numptr); |
| 131 | |
| 132 | /** |
| 133 | * fifo8_peek_bufptr: read upto max bytes from the fifo |
| 134 | * @fifo: FIFO to read from |
| 135 | * @max: maximum number of bytes to peek |
| 136 | * @numptr: pointer filled with number of bytes returned (can be NULL) |
| 137 | * |
| 138 | * Peek into a number of elements from the FIFO up to a maximum of @max. |
| 139 | * The buffer containing the data peeked into is returned. This buffer points |
| 140 | * directly into the FIFO backing store. Since data is invalidated once any |
| 141 | * of the fifo8_* APIs are called on the FIFO, it is the caller responsibility |
| 142 | * to access it before doing further API calls. |
| 143 | * |
| 144 | * The function may return fewer bytes than requested when the data wraps |
| 145 | * around in the ring buffer; in this case only a contiguous part of the data |
| 146 | * is returned. |
| 147 | * |
| 148 | * The number of valid bytes returned is populated in *@numptr; will always |
| 149 | * return at least 1 byte. max must not be 0 or greater than the number of |
| 150 | * bytes in the FIFO. |
| 151 | * |
| 152 | * Clients are responsible for checking the availability of requested data |
| 153 | * using fifo8_num_used(). |
| 154 | * |
| 155 | * Returns: A pointer to peekable data. |
| 156 | */ |
| 157 | const uint8_t *fifo8_peek_bufptr(Fifo8 *fifo, uint32_t max, uint32_t *numptr); |
| 158 | |
| 159 | /** |
| 160 | * fifo8_drop: |
| 161 | * @fifo: FIFO to drop bytes |
| 162 | * @len: number of bytes to drop |
| 163 | * |
| 164 | * Drop (consume) bytes from a FIFO. |
| 165 | */ |
| 166 | void fifo8_drop(Fifo8 *fifo, uint32_t len); |
| 167 | |
| 168 | /** |
| 169 | * fifo8_reset: |
| 170 | * @fifo: FIFO to reset |
| 171 | * |
| 172 | * Reset a FIFO. All data is discarded and the FIFO is emptied. |
| 173 | */ |
| 174 | void fifo8_reset(Fifo8 *fifo); |
| 175 | |
| 176 | /** |
| 177 | * fifo8_is_empty: |
| 178 | * @fifo: FIFO to check |
| 179 | * |
| 180 | * Check if a FIFO is empty. |
| 181 | * |
| 182 | * Returns: True if the fifo is empty, false otherwise. |
| 183 | */ |
| 184 | bool fifo8_is_empty(const Fifo8 *fifo); |
| 185 | |
| 186 | /** |
| 187 | * fifo8_is_full: |
| 188 | * @fifo: FIFO to check |
| 189 | * |
| 190 | * Check if a FIFO is full. |
| 191 | * |
| 192 | * Returns: True if the fifo is full, false otherwise. |
| 193 | */ |
| 194 | bool fifo8_is_full(const Fifo8 *fifo); |
| 195 | |
| 196 | /** |
| 197 | * fifo8_num_free: |
| 198 | * @fifo: FIFO to check |
| 199 | * |
| 200 | * Return the number of free bytes in the FIFO. |
| 201 | * |
| 202 | * Returns: Number of free bytes. |
| 203 | */ |
| 204 | uint32_t fifo8_num_free(const Fifo8 *fifo); |
| 205 | |
| 206 | /** |
| 207 | * fifo8_num_used: |
| 208 | * @fifo: FIFO to check |
| 209 | * |
| 210 | * Return the number of used bytes in the FIFO. |
| 211 | * |
| 212 | * Returns: Number of used bytes. |
| 213 | */ |
| 214 | uint32_t fifo8_num_used(const Fifo8 *fifo); |
| 215 | |
| 216 | extern const VMStateDescription vmstate_fifo8; |
| 217 | |
| 218 | #define VMSTATE_FIFO8_TEST(_field, _state, _test) { \ |
| 219 | .name = (stringify(_field)), \ |
| 220 | .field_exists = (_test), \ |
| 221 | .size = sizeof(Fifo8), \ |
| 222 | .vmsd = &vmstate_fifo8, \ |
| 223 | .flags = VMS_STRUCT, \ |
| 224 | .offset = vmstate_offset_value(_state, _field, Fifo8), \ |
| 225 | } |
| 226 | |
| 227 | #define VMSTATE_FIFO8(_field, _state) \ |
| 228 | VMSTATE_FIFO8_TEST(_field, _state, NULL) |
| 229 | |
| 230 | #endif /* QEMU_FIFO8_H */ |