/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 2024 Mike Becker, Olaf Wintermann All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/**
* @file properties.h
* @brief Interface for parsing data from properties files.
* @author Mike Becker
* @author Olaf Wintermann
* @copyright 2-Clause BSD License
*/
#ifndef UCX_PROPERTIES_H
#define UCX_PROPERTIES_H
#include "common.h"
#include "string.h"
#include "map.h"
#include "buffer.h"
#include <stdio.h>
#include <string.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* Configures the expected characters for the properties parser.
*/
struct cx_properties_config_s {
/**
* The key/value delimiter that shall be used.
* This is '=' by default.
*/
char delimiter;
/**
* The first comment character.
* This is '#' by default.
*/
char comment1;
/**
* The second comment character.
* This is not set by default.
*/
char comment2;
/**
* The third comment character.
* This is not set by default.
*/
char comment3;
/*
* The character, when appearing at the end of a line, continues that line.
* This is '\' by default.
*/
/**
* Reserved for future use.
*/
char continuation;
};
/**
* Typedef for the properties config.
*/
typedef struct cx_properties_config_s CxPropertiesConfig;
/**
* Default properties configuration.
*/
CX_EXPORT extern const CxPropertiesConfig cx_properties_config_default;
/**
* Status codes for the properties interface.
*/
enum cx_properties_status {
/**
* Everything is fine.
*/
CX_PROPERTIES_NO_ERROR,
/**
* The input buffer does not contain more data.
*/
CX_PROPERTIES_NO_DATA,
/**
* The input ends unexpectedly.
*
* This either happens when the last line does not terminate with a line
* break, or when the input ends with a parsed key but no value.
*/
CX_PROPERTIES_INCOMPLETE_DATA,
/**
* Not used as a status and never returned by any function.
*
* You can use this enumerator to check for all "good" status results
* by checking if the status is less than @c CX_PROPERTIES_OK.
*
* A "good" status means that you can refill data and continue parsing.
*/
CX_PROPERTIES_OK,
/**
* Input buffer is @c NULL.
*/
CX_PROPERTIES_NULL_INPUT,
/**
* The line contains a delimiter but no key.
*/
CX_PROPERTIES_INVALID_EMPTY_KEY,
/**
* The line contains data but no delimiter.
*/
CX_PROPERTIES_INVALID_MISSING_DELIMITER,
/**
* More internal buffer was needed, but could not be allocated.
*/
CX_PROPERTIES_BUFFER_ALLOC_FAILED,
/**
* Initializing the properties source failed.
*
* @see cx_properties_read_init_func
*/
CX_PROPERTIES_READ_INIT_FAILED,
/**
* Reading from a properties source failed.
*
* @see cx_properties_read_func
*/
CX_PROPERTIES_READ_FAILED,
/**
* Sinking a k/v-pair failed.
*
* @see cx_properties_sink_func
*/
CX_PROPERTIES_SINK_FAILED,
};
/**
* Typedef for the properties status enum.
*/
typedef enum cx_properties_status CxPropertiesStatus;
/**
* Interface for working with properties data.
*/
struct cx_properties_s {
/**
* The configuration.
*/
CxPropertiesConfig config;
/**
* The text input buffer.
*/
CxBuffer input;
/**
* Internal buffer.
*/
CxBuffer buffer;
};
/**
* Typedef for the properties interface.
*/
typedef struct cx_properties_s CxProperties;
/**
* Typedef for a properties sink.
*/
typedef struct cx_properties_sink_s CxPropertiesSink;
/**
* A function that consumes a k/v-pair in a sink.
*
* The sink could be a map, and the sink function would be calling
* a map function to store the k/v-pair.
*
* @param prop the properties interface that wants to sink a k/v-pair
* @param sink the sink
* @param key the key
* @param value the value
* @retval zero success
* @retval non-zero sinking the k/v-pair failed
*/
typedef int(*cx_properties_sink_func)(
CxProperties *prop,
CxPropertiesSink *sink,
cxstring key,
cxstring value
);
/**
* Defines a sink for k/v-pairs.
*/
struct cx_properties_sink_s {
/**
* The sink object.
*/
void *sink;
/**
* Optional custom data.
*/
void *data;
/**
* A function for consuming k/v-pairs into the sink.
*/
cx_properties_sink_func sink_func;
};
/**
* Typedef for a properties source.
*/
typedef struct cx_properties_source_s CxPropertiesSource;
/**
* A function that reads data from a source.
*
* When the source is depleted, implementations SHALL provide an empty
* string in the @p target and return zero.
* A non-zero return value is only permitted in case of an error.
*
* The meaning of the optional parameters is implementation-dependent.
*
* @param prop the properties interface that wants to read from the source
* @param src the source
* @param target a string buffer where the read data shall be stored
* @retval zero success
* @retval non-zero reading the data failed
*/
typedef int(*cx_properties_read_func)(
CxProperties *prop,
CxPropertiesSource *src,
cxstring *target
);
/**
* A function that may initialize additional memory for the source.
*
* @param prop the properties interface that wants to read from the source
* @param src the source
* @retval zero initialization was successful
* @retval non-zero otherwise
*/
typedef int(*cx_properties_read_init_func)(
CxProperties *prop,
CxPropertiesSource *src
);
/**
* A function that cleans memory initialized by the read_init_func.
*
* @param prop the properties interface that wants to read from the source
* @param src the source
*/
typedef void(*cx_properties_read_clean_func)(
CxProperties *prop,
CxPropertiesSource *src
);
/**
* Defines a properties source.
*/
struct cx_properties_source_s {
/**
* The source object.
*
* For example, a file stream or a string.
*/
void *src;
/**
* Optional additional data pointer.
*/
void *data_ptr;
/**
* Optional size information.
*/
size_t data_size;
/**
* A function that reads data from the source.
*/
cx_properties_read_func read_func;
/**
* Optional function that may prepare the source for reading data.
*/
cx_properties_read_init_func read_init_func;
/**
* Optional function that cleans additional memory allocated by the
* read_init_func.
*/
cx_properties_read_clean_func read_clean_func;
};
/**
* Initialize a properties interface.
*
* @param prop the properties interface
* @param config the properties configuration
* @see cxPropertiesInitDefault()
*/
cx_attr_nonnull
CX_EXPORT void cxPropertiesInit(CxProperties *prop, CxPropertiesConfig config);
/**
* Destroys the properties interface.
*
* @note Even when you are certain that you did not use the interface in a
* way that caused a memory allocation, you should call this function anyway.
* Future versions of the library might add features that need additional memory,
* and you really don't want to search the entire code where you might need to
* add a call to this function.
*
* @param prop the properties interface
*/
cx_attr_nonnull
CX_EXPORT void cxPropertiesDestroy(CxProperties *prop);
/**
* Destroys and re-initializes the properties interface.
*
* You might want to use this to reset the parser after
* encountering a syntax error.
*
* @param prop the properties interface
*/
cx_attr_nonnull
CX_EXPORT void cxPropertiesReset(CxProperties *prop);
/**
* Initialize a properties parser with the default configuration.
*
* @param prop (@c CxProperties*) the properties interface
* @see cxPropertiesInit()
*/
#define cxPropertiesInitDefault(prop) \
cxPropertiesInit(prop, cx_properties_config_default)
/**
* Fills the input buffer with data.
*
* After calling this function, you can parse the data by calling
* cxPropertiesNext().
*
* @remark The properties interface tries to avoid allocations.
* When you use this function and cxPropertiesNext() interleaving,
* no allocations are performed. However, you must not free the
* pointer to the data in that case. When you invoke the fill
* function more than once before calling cxPropertiesNext(),
* the additional data is appended - inevitably leading to
* an allocation of a new buffer and copying the previous contents.
*
* @param prop the properties interface
* @param buf a pointer to the data
* @param len the length of the data
* @retval zero success
* @retval non-zero a memory allocation was necessary but failed
* @see cxPropertiesFill()
*/
cx_attr_nonnull cx_attr_access_r(2, 3)
CX_EXPORT int cxPropertiesFilln(CxProperties *prop, const char *buf, size_t len);
/**
* Internal function, do not use.
*
* @param prop the properties interface
* @param str the text to fill in
* @retval zero success
* @retval non-zero a memory allocation was necessary but failed
*/
cx_attr_nonnull
CX_INLINE int cx_properties_fill(CxProperties *prop, cxstring str) {
return cxPropertiesFilln(prop, str.ptr, str.length);
}
/**
* Fills the input buffer with data.
*
* After calling this function, you can parse the data by calling
* cxPropertiesNext().
*
* @attention The properties interface tries to avoid allocations.
* When you use this function and cxPropertiesNext() interleaving,
* no allocations are performed. However, you must not free the
* pointer to the data in that case. When you invoke the fill
* function more than once before calling cxPropertiesNext(),
* the additional data is appended - inevitably leading to
* an allocation of a new buffer and copying the previous contents.
*
* @param prop the properties interface
* @param str the text to fill in
* @retval zero success
* @retval non-zero a memory allocation was necessary but failed
* @see cxPropertiesFilln()
*/
#define cxPropertiesFill(prop, str) cx_properties_fill(prop, cx_strcast(str))
/**
* Specifies stack memory that shall be used as an internal buffer.
*
* @param prop the properties interface
* @param buf a pointer to stack memory
* @param capacity the capacity of the stack memory
*/
cx_attr_nonnull
CX_EXPORT void cxPropertiesUseStack(CxProperties *prop, char *buf, size_t capacity);
/**
* Retrieves the next key/value-pair.
*
* This function returns zero as long as there are key/value-pairs found.
* If no more key/value-pairs are found, #CX_PROPERTIES_NO_DATA is returned.
*
* When an incomplete line is encountered, #CX_PROPERTIES_INCOMPLETE_DATA is
* returned, and you can add more data with #cxPropertiesFill().
*
* @remark The incomplete line will be stored in an internal buffer, which is
* allocated on the heap, by default. If you want to avoid allocations,
* you can specify sufficient space with cxPropertiesUseStack() after
* initialization with cxPropertiesInit().
*
* @attention The returned strings will point into a buffer that might not be
* available later. It is strongly recommended to copy the strings for further
* use.
*
* @param prop the properties interface
* @param key a pointer to the cxstring that shall contain the property name
* @param value a pointer to the cxstring that shall contain the property value
* @retval CX_PROPERTIES_NO_ERROR (zero) a key/value pair was found
* @retval CX_PROPERTIES_NO_DATA there is no (more) data in the input buffer
* @retval CX_PROPERTIES_INCOMPLETE_DATA the data in the input buffer is incomplete
* (fill more data and try again)
* @retval CX_PROPERTIES_NULL_INPUT the input buffer was never filled
* @retval CX_PROPERTIES_INVALID_EMPTY_KEY the properties data contains an illegal empty key
* @retval CX_PROPERTIES_INVALID_MISSING_DELIMITER the properties data contains a line without delimiter
* @retval CX_PROPERTIES_BUFFER_ALLOC_FAILED an internal allocation was necessary but failed
*/
cx_attr_nonnull cx_attr_nodiscard
CX_EXPORT CxPropertiesStatus cxPropertiesNext(CxProperties *prop, cxstring *key, cxstring *value);
/**
* Creates a properties sink for an UCX map.
*
* The values stored in the map will be pointers to freshly allocated,
* zero-terminated C strings (@c char*), which means the @p map should have been
* created with #CX_STORE_POINTERS.
*
* The cxDefaultAllocator will be used unless you specify a custom
* allocator in the optional @c data field of the returned sink.
*
* @param map the map that shall consume the k/v-pairs.
* @return the sink
* @see cxPropertiesLoad()
*/
cx_attr_nonnull cx_attr_nodiscard
CX_EXPORT CxPropertiesSink cxPropertiesMapSink(CxMap *map);
/**
* Creates a properties source based on an UCX string.
*
* @param str the string
* @return the properties source
* @see cxPropertiesLoad()
*/
cx_attr_nodiscard
CX_EXPORT CxPropertiesSource cxPropertiesStringSource(cxstring str);
/**
* Creates a properties source based on C string with the specified length.
*
* @param str the string
* @param len the length
* @return the properties source
* @see cxPropertiesLoad()
*/
cx_attr_nonnull cx_attr_nodiscard cx_attr_access_r(1, 2)
CX_EXPORT CxPropertiesSource cxPropertiesCstrnSource(const char *str, size_t len);
/**
* Creates a properties source based on a C string.
*
* The length will be determined with strlen(), so the string MUST be
* zero-terminated.
*
* @param str the string
* @return the properties source
* @see cxPropertiesLoad()
*/
cx_attr_nonnull cx_attr_nodiscard cx_attr_cstr_arg(1)
CX_EXPORT CxPropertiesSource cxPropertiesCstrSource(const char *str);
/**
* Creates a properties source based on an FILE.
*
* @param file the file
* @param chunk_size how many bytes may be read in one operation
*
* @return the properties source
* @see cxPropertiesLoad()
*/
cx_attr_nonnull cx_attr_nodiscard cx_attr_access_r(1)
CX_EXPORT CxPropertiesSource cxPropertiesFileSource(FILE *file, size_t chunk_size);
/**
* Loads properties data from a source and transfers it to a sink.
*
* This function tries to read as much data from the source as possible.
* When the source was completely consumed and at least on k/v-pair was found,
* the return value will be #CX_PROPERTIES_NO_ERROR.
* When the source was consumed but no k/v-pairs were found, the return value
* will be #CX_PROPERTIES_NO_DATA.
* In case the source data ends unexpectedly, the #CX_PROPERTIES_INCOMPLETE_DATA
* is returned. In that case you should call this function again with the same
* sink and either an updated source or the same source if the source is able to
* yield the missing data.
*
* The other result codes apply, according to their description.
*
* @param prop the properties interface
* @param sink the sink
* @param source the source
* @retval CX_PROPERTIES_NO_ERROR (zero) a key/value pair was found
* @retval CX_PROPERTIES_READ_INIT_FAILED initializing the source failed
* @retval CX_PROPERTIES_READ_FAILED reading from the source failed
* @retval CX_PROPERTIES_SINK_FAILED sinking the properties into the sink failed
* @retval CX_PROPERTIES_NO_DATA the source did not provide any key/value pairs
* @retval CX_PROPERTIES_INCOMPLETE_DATA the source did not provide enough data
* @retval CX_PROPERTIES_INVALID_EMPTY_KEY the properties data contains an illegal empty key
* @retval CX_PROPERTIES_INVALID_MISSING_DELIMITER the properties data contains a line without delimiter
* @retval CX_PROPERTIES_BUFFER_ALLOC_FAILED an internal allocation was necessary but failed
*/
cx_attr_nonnull
CX_EXPORT CxPropertiesStatus cxPropertiesLoad(CxProperties *prop,
CxPropertiesSink sink, CxPropertiesSource source);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // UCX_PROPERTIES_H