diff options
Diffstat (limited to 'lib/data.h')
| -rw-r--r-- | lib/data.h | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/lib/data.h b/lib/data.h new file mode 100644 index 0000000..7072ba9 --- /dev/null +++ b/lib/data.h @@ -0,0 +1,209 @@ +/* PipeWire AGL Cluster IPC + * + * Copyright © 2018 Wim Taymans + * Copyright © 2021 Collabora Ltd. + * @author George Kiagiadakis <george.kiagiadakis@collabora.com> + * + * SPDX-License-Identifier: MIT + */ + +#include <assert.h> +#include <stddef.h> +#include <stdint.h> +#include <stdbool.h> +#include <string.h> + +/* Trimmed down version of struct spa_pod from PipeWire's Simple Plugin API + * This aims to be compatible with spa_pod, so you can cast icipc_data + * to spa_pod and still be able to use it */ + +struct icipc_data { + uint32_t size; /* size of the body */ + uint32_t type; /* type of the body */ + /* type-specific body follows */ +}; + +#define ICIPC_DATA_BODY_SIZE(d) (((const struct icipc_data*)(d))->size) +#define ICIPC_DATA_TYPE(d) (((const struct icipc_data*)(d))->type) +#define ICIPC_DATA_SIZE(d) (sizeof(struct icipc_data) + ICIPC_DATA_BODY_SIZE(d)) +#define ICIPC_DATA_BODY(d) ((void*)(((uint8_t *) d) + sizeof(struct icipc_data))) +#define ICIPC_DATA_BODY_CONST(d) ((const void*)(((const uint8_t *) d) + sizeof(struct icipc_data))) + +enum { + DATA_TYPE_NONE = 1, /* SPA_TYPE_None */ + DATA_TYPE_ID = 3, /* SPA_TYPE_Id */ + DATA_TYPE_INT = 4, /* SPA_TYPE_Int */ + DATA_TYPE_STRING = 8, /* SPA_TYPE_String */ + DATA_TYPE_STRUCT = 14, /* SPA_TYPE_Struct */ +}; + +#define PTR_ALIGNMENT 8 +#define ROUND_UP_TO_ALIGN(num) (((num) + (PTR_ALIGNMENT - 1)) & ~((PTR_ALIGNMENT) - 1)) +#define PTR_IS_ALIGNED(p) (((intptr_t)(p) & (PTR_ALIGNMENT-1)) == 0) + +typedef struct DataBuilder { + union { + uint8_t *buffer; + struct icipc_data *data; + }; + union { + uint8_t *ptr; + struct icipc_data *ptr_as_data; + }; + size_t buf_size; +} DataBuilder; + +typedef struct DataParser { + union { + const uint8_t *buffer; + const struct icipc_data *data; + }; + union { + const uint8_t *ptr; + const struct icipc_data *ptr_as_data; + }; + size_t buf_size; +} DataParser; + +static inline void data_builder_init( + DataBuilder *b, + uint8_t *buffer, + size_t size) { + assert(size >= sizeof(struct icipc_data)); + memset(buffer, 0, size); + b->buffer = buffer; + b->buf_size = size; + b->data->type = DATA_TYPE_STRUCT; + b->ptr = ICIPC_DATA_BODY(b->data); + assert(PTR_IS_ALIGNED(b->ptr)); +} + +static inline size_t data_type_id_calc_size(void) { + return sizeof(struct icipc_data) + ROUND_UP_TO_ALIGN(sizeof(uint32_t)); +} + +static inline void data_builder_push_id(DataBuilder *b, uint32_t id) { + + const size_t body_size = ROUND_UP_TO_ALIGN(sizeof(uint32_t)); + const size_t additional_size = sizeof(struct icipc_data) + body_size; + assert(b->buf_size >= ICIPC_DATA_SIZE(b->data) + additional_size); + + b->ptr_as_data->size = body_size; + b->ptr_as_data->type = DATA_TYPE_ID; + *((uint32_t *) ICIPC_DATA_BODY(b->ptr)) = id; + + b->data->size += additional_size; + b->ptr += additional_size; + assert(PTR_IS_ALIGNED(b->ptr)); +} + +static inline size_t data_type_string_calc_size(const char *str) { + size_t str_size = strlen(str) + 1; + return sizeof(struct icipc_data) + ROUND_UP_TO_ALIGN(str_size); +} + +static inline void data_builder_push_string(DataBuilder *b, const char *str) { + + size_t str_size = strlen(str) + 1; + const size_t body_size = ROUND_UP_TO_ALIGN(str_size); + const size_t additional_size = sizeof(struct icipc_data) + body_size; + assert(b->buf_size >= ICIPC_DATA_SIZE(b->data) + additional_size); + + b->ptr_as_data->size = body_size; + b->ptr_as_data->type = DATA_TYPE_STRING; + strncpy((char *) ICIPC_DATA_BODY(b->ptr), str, str_size); + + b->data->size += additional_size; + b->ptr += additional_size; + assert(PTR_IS_ALIGNED(b->ptr)); +} + +static inline size_t data_type_raw_calc_size(const struct icipc_data *raw) { + return sizeof(struct icipc_data) + + ROUND_UP_TO_ALIGN(ICIPC_DATA_BODY_SIZE(raw)); +} + +static inline void data_builder_push_raw( + DataBuilder *b, + const struct icipc_data *raw) { + + const size_t body_size = ROUND_UP_TO_ALIGN(ICIPC_DATA_BODY_SIZE(raw)); + const size_t additional_size = sizeof(struct icipc_data) + body_size; + assert(b->buf_size >= ICIPC_DATA_SIZE(b->data) + additional_size); + + b->ptr_as_data->size = body_size; + b->ptr_as_data->type = raw->type; + memcpy(ICIPC_DATA_BODY(b->ptr), + ICIPC_DATA_BODY(raw), + ICIPC_DATA_BODY_SIZE(raw)); + + b->data->size += additional_size; + b->ptr += additional_size; + assert(PTR_IS_ALIGNED(b->ptr)); +} + +static inline bool data_parser_init( + DataParser *p, + const uint8_t *buffer, + size_t size) { + assert(size >= sizeof(struct icipc_data)); + p->buffer = buffer; + p->buf_size = size; + + if (p->data->type != DATA_TYPE_STRUCT || + ICIPC_DATA_SIZE(p->data) > size) + return false; + + p->ptr = ICIPC_DATA_BODY(p->data); + assert(PTR_IS_ALIGNED(p->ptr)); + return true; +} + +static inline bool data_parser_get_id(DataParser *p, uint32_t *id) { + + if (p->ptr_as_data->type != DATA_TYPE_ID || + ICIPC_DATA_BODY_SIZE(p->ptr) != ROUND_UP_TO_ALIGN(sizeof(uint32_t))) + return false; + + *id = *((const uint32_t *) ICIPC_DATA_BODY_CONST(p->ptr)); + + p->ptr += ICIPC_DATA_SIZE(p->ptr); + assert(PTR_IS_ALIGNED(p->ptr)); + return true; +} + +static inline bool data_parser_get_string(DataParser *p, const char **str) { + + if (p->ptr_as_data->type != DATA_TYPE_STRING || + ICIPC_DATA_BODY_SIZE(p->ptr) == 0 || + ICIPC_DATA_BODY_SIZE(p->ptr) != + ROUND_UP_TO_ALIGN(ICIPC_DATA_BODY_SIZE(p->ptr)) || + (p->ptr - p->buffer) + ICIPC_DATA_SIZE(p->ptr) > p->buf_size) + return false; + + *str = (const char *) ICIPC_DATA_BODY_CONST(p->ptr); + + /* check that the string has a terminating null character */ + if (strnlen(*str, ICIPC_DATA_BODY_SIZE(p->ptr)) == + ICIPC_DATA_BODY_SIZE(p->ptr)) + return false; + + p->ptr += ICIPC_DATA_SIZE(p->ptr); + assert(PTR_IS_ALIGNED(p->ptr)); + return true; +} + +static inline bool data_parser_get_raw( + DataParser *p, + const struct icipc_data **raw) { + if (ICIPC_DATA_BODY_SIZE(p->ptr) != + ROUND_UP_TO_ALIGN(ICIPC_DATA_BODY_SIZE(p->ptr)) || + (p->ptr - p->buffer) + ICIPC_DATA_SIZE(p->ptr) > p->buf_size) + return false; + + *raw = p->ptr_as_data; + + p->ptr += ICIPC_DATA_SIZE(p->ptr); + assert(PTR_IS_ALIGNED(p->ptr)); + return true; +} |