status_t persist_delete | ( | const uint32_t | key | ) |
Deletes the value of a key from persistent storage.
key | The key of the field to delete from. |
bool persist_exists | ( | const uint32_t | key | ) |
Checks whether a value has been set for a given key in persistent storage.
key | The key of the field to check. |
int persist_get_size | ( | const uint32_t | key | ) |
Gets the size of a value for a given key in persistent storage.
key | The key of the field to lookup the data size. |
bool persist_read_bool | ( | const uint32_t | key | ) |
Reads a bool value for a given key from persistent storage. If the value has not yet been set, this will return false.
key | The key of the field to read from. |
Reads a blob of data for a given key from persistent storage into a given buffer. If the value has not yet been set, the given buffer is left unchanged.
key | The key of the field to read from. |
buffer | The pointer to a buffer to be written to. |
buffer_size | The maximum size of the given buffer. |
int32_t persist_read_int | ( | const uint32_t | key | ) |
Reads an int value for a given key from persistent storage.
key | The key of the field to read from. |
Reads a string for a given key from persistent storage into a given buffer. The string will be null terminated. If the value has not yet been set, the given buffer is left unchanged.
key | The key of the field to read from. |
buffer | The pointer to a buffer to be written to. |
buffer_size | The maximum size of the given buffer. This includes the null character. |
status_t persist_write_bool | ( | const uint32_t | key, |
const bool | value | ||
) |
Writes a bool value flag for a given key into persistent storage.
key | The key of the field to write to. |
value | The boolean value to write. |
Writes a blob of data of a specified size in bytes for a given key into persistent storage. The maximum size is PERSIST_DATA_MAX_LENGTH.
key | The key of the field to write to. |
data | The pointer to the blob of data. |
size | The size in bytes. |
status_t persist_write_int | ( | const uint32_t | key, |
const int32_t | value | ||
) |
Writes an int value for a given key into persistent storage.
key | The key of the field to write to. |
value | The int value to write. |
int persist_write_string | ( | const uint32_t | key, |
const char * | cstring | ||
) |
Writes a string a given key into persistent storage. The maximum size is PERSIST_STRING_MAX_LENGTH including the null terminator.
key | The key of the field to write to. |
cstring | The pointer to null terminated string. |
#define PERSIST_DATA_MAX_LENGTH 256 |
The maximum size of a persist value in bytes.
#define PERSIST_STRING_MAX_LENGTH PERSIST_DATA_MAX_LENGTH |
The maximum size of a persist string in bytes including the NULL terminator.