libwildlifesystems

WildlifeSystems shared sensor utilities - a static library providing common functionality for sensor drivers.

Features

• JSON utilities: String escaping, null value replacement for strings, numbers, booleans
• JSON building: Construct sensor JSON output with proper structure
• Prototype caching: Integration with sc-prototype for JSON templates
• Command handlers: Standard identify, list, and version command implementations
• System utilities: GPIO pin validation, Raspberry Pi serial number retrieval
• Standard exit codes: WS_EXIT_SUCCESS, WS_EXIT_IDENTIFY, WS_EXIT_INVALID_ARG

Installation

From Debian package

sudo dpkg -i libwildlifesystems-dev_1.1.1_armhf.deb

From source

make
sudo make install

Usage

Include the header and link against the static library:

#include <ws/ws_utils.h>

Compile with:

gcc -o my_sensor my_sensor.c -lws_utils

Or with the include path:

gcc -I/usr/include/ws -o my_sensor my_sensor.c -L/usr/lib -lws_utils

API Reference

Exit Codes

#define WS_EXIT_SUCCESS     0
#define WS_EXIT_IDENTIFY    60
#define WS_EXIT_INVALID_ARG 20

Location Filter

typedef enum {
    WS_LOCATION_ALL = 0,
    WS_LOCATION_INTERNAL,
    WS_LOCATION_EXTERNAL
} ws_location_filter_t;

Functions

Function	Description
ws_json_escape_string()	Escape string for JSON
ws_json_replace_null_string()	Replace null with string value
ws_json_replace_null_number()	Replace null with double value
ws_json_replace_null_int()	Replace null with long value
ws_json_replace_null_bool()	Replace null with boolean
ws_get_sc_prototype()	Get JSON prototype (caller frees)
ws_get_prototype_cached()	Get cached JSON prototype
ws_get_timestamp()	Get current Unix timestamp
ws_cmd_identify()	Handle identify command (exits)
ws_cmd_list_single()	Handle list with one measurement (exits)
ws_cmd_list_multiple()	Handle list with multiple measurements (exits)
ws_get_serial_number()	Get Pi serial number (caller frees)
ws_get_serial_with_suffix()	Get Pi serial with suffix (caller frees)
ws_validate_gpio_pin()	Validate GPIO pin (2-27)
ws_print_version()	Print version information
ws_build_sensor_json_base()	Build base sensor JSON structure
ws_sensor_json_set_value()	Set the value field in sensor JSON
ws_build_config_base()	Build config JSON with version info

License

GPL-2+