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134 lines
4.4 KiB
134 lines
4.4 KiB
/* Copyright 2016 Alex 'AdUser' Z (ad_user@runbox.com) |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License version 2 as |
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* published by the Free Software Foundation. |
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*/ |
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#include <assert.h> |
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#include <errno.h> |
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#include <stdbool.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <unistd.h> |
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#include "../strlcpy.h" |
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/** |
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* @file |
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* This header describes module API of type 'source' |
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* |
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* Sample workflow of module usage: |
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* |
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* @msc |
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* f2b, source; |
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* f2b => source [label="create(init)"]; |
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* f2b << source [label="module handler, cfg_t *cfg"]; |
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* |||; |
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* f2b => source [label="config(cfg, param, value)"]; |
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* f2b << source [label="true"]; |
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* f2b => source [label="config(cfg, param, value)"]; |
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* f2b << source [label="true"]; |
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* f2b => source [label="config(cfg, param, value)"]; |
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* f2b << source [label="false"]; |
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* f2b => source [label="error(cfg)"]; |
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* f2b << source [label="const char *error"]; |
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* |||; |
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* f2b => source [label="errcb(cfg, cb), optional"]; |
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* |||; |
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* f2b => source [label="ready(cfg)"]; |
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* f2b << source [label="true"]; |
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* --- [label="source is ready for start()"]; |
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* f2b => source [label="start()"]; |
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* f2b << source [label="true"]; |
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* --- [label="source is ready to use"]; |
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* f2b => source [label="next(cfg, buf, sizeof(buf), true)"]; |
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* f2b << source [label="false"]; |
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* ... [label="no data this time, try later"]; |
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* f2b => source [label="next(cfg, buf, sizeof(buf), true)"]; |
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* f2b << source [label="true"]; |
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* f2b => source [label="next(cfg, buf, sizeof(buf), false)"]; |
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* f2b <<= source [label="errcb(char *error)"]; |
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* f2b << source [label="true"]; |
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* f2b => source [label="next(cfg, buf, sizeof(buf), false)"]; |
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* f2b << source [label="false"]; |
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* ... [label="time passed"]; |
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* f2b => source [label="stop(cfg)"]; |
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* f2b << source [label="true"]; |
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* --- [label="now you may config(), start() or destroy() source"]; |
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* f2b => source [label="destroy(cfg)"]; |
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* @endmsc |
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*/ |
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/** |
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* @def INIT_MAX |
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* Defines max length of @a init param in @a create() |
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*/ |
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#define INIT_MAX 256 |
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/** |
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* Opaque module handler, contains module internal structs |
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*/ |
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typedef struct _config cfg_t; |
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/** |
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* @brief Create instance of module |
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* @param init Module-specific init string |
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* @returns Opaque module handler or NULL on failure |
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*/ |
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extern cfg_t *create(const char *init); |
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/** |
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* @brief Configure module instance |
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* @param cfg Module handler |
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* @param key Parameter name |
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* @param value Parameter value |
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* @returns true on success, false on error with setting intenal error buffer |
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*/ |
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extern bool config(cfg_t *cfg, const char *key, const char *value); |
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/** |
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* @brief Checks is module ready for usage |
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* @param cfg Module handler |
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* @returns true if ready, false if not |
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*/ |
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extern bool ready(cfg_t *cfg); |
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/** |
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* @brief Returns last error description |
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* @param cfg Module handler |
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* @returns Pointer to string with description of last error |
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* @note Returned pointer not marked with const, because libdl complains, |
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* but contents on pointer should not be modified or written in any way |
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*/ |
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extern char *error(cfg_t *cfg); |
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/** |
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* @brief Sets the error callback for use in processing |
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* @param cfg Module handler |
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* @param cb Error callback |
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* @note Optional, if this function is not called, processing errors will be suppressed |
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*/ |
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extern void errcb(cfg_t *cfg, void (*cb)(const char *errstr)); |
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/** |
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* @brief Allocate resources and start processing |
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* @param cfg Module handler |
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* @returns true on success, false on error with setting intenal error buffer |
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*/ |
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extern bool start(cfg_t *cfg); |
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/** |
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* @brief Poll source for new data |
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* @param cfg Module handler |
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* @param buf Pointer to buffer for storing result |
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* @param bufsize Size of buffer above (in bytes) |
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* @param reset Reset internals to start of list |
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* @returns false if no new data available, or true otherwise with filling @a buf |
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*/ |
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extern bool next(cfg_t *cfg, char *buf, size_t bufsize, bool reset); |
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/** |
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* @brief Deallocate resources, prepare for module destroy |
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* @param cfg Module handler |
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* @returns true on success |
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*/ |
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extern bool stop(cfg_t *cfg); |
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/** |
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* @brief Free module handle |
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* @param cfg Module handler |
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* @note Module handler becomes invalid after calling this function on it |
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*/ |
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extern void destroy(cfg_t *cfg);
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