ossp-pkg/var/varexp.h
#ifndef LIB_VARIABLE_EXPAND_H
#define LIB_VARIABLE_EXPAND_H
#include <stdlib.h>
/* Error codes returned by the varexp library. */
typedef enum
{
VAR_EMPTY_PADDING_FILL_STRING = -32,
VAR_MISSING_PADDING_WIDTH = -31,
VAR_MALFORMATTED_PADDING = -30,
VAR_INCORRECT_TRANSPOSE_CLASS_SPEC = -29,
VAR_EMPTY_TRANSPOSE_CLASS = -28,
VAR_TRANSPOSE_CLASSES_MISMATCH = -27,
VAR_MALFORMATTED_TRANSPOSE = -26,
VAR_OFFSET_LOGIC_ERROR = -25,
VAR_OFFSET_OUT_OF_BOUNDS = -24,
VAR_RANGE_OUT_OF_BOUNDS = -23,
VAR_INVALID_OFFSET_DELIMITER = -22,
VAR_MISSING_START_OFFSET = -21,
VAR_EMPTY_SEARCH_STRING = -20,
VAR_MISSING_PARAMETER_IN_COMMAND = -19,
VAR_INVALID_REGEX_IN_REPLACE = -18,
VAR_UNKNOWN_REPLACE_FLAG = -17,
VAR_MALFORMATTED_REPLACE = -16,
VAR_UNKNOWN_COMMAND_CHAR = -14,
VAR_INPUT_ISNT_TEXT_NOR_VARIABLE = -13,
VAR_UNDEFINED_VARIABLE = -12,
VAR_INCOMPLETE_VARIABLE_SPEC = -11,
VAR_OUT_OF_MEMORY = -10,
VAR_INVALID_CONFIGURATION = -9,
VAR_INCORRECT_CLASS_SPEC = -8,
VAR_INCOMPLETE_GROUPED_HEX = -7,
VAR_INCOMPLETE_OCTAL = -6,
VAR_INVALID_OCTAL = -5,
VAR_OCTAL_TOO_LARGE = -4,
VAR_INVALID_HEX = -3,
VAR_INCOMPLETE_HEX = -2,
VAR_INCOMPLETE_NAMED_CHARACTER = -1,
VAR_INCOMPLETE_QUOTED_PAIR = -1,
VAR_OK = 0
}
var_rc_t;
/*
Expand the following named characters to their binary
representation:
\t tab
\n newline
\r return
\033 octal char
\x1B hex char
\x{263a} wide hex char
Any other character quoted by a backslash is copied verbatim.
*/
var_rc_t expand_named_characters(const char* src, size_t len, char* dst);
/*
The callback will be called by variable_expand(), providing the
following parameterns:
context - passed through from variable_expand()'s
parameters
varname - pointer to the name of the variable to
expand
name_len - length of the string starting at varname
data - location, where the callback should store
the pointer to the contents of the looked-up
variable
data_len - location, where the callback should store
the length of the data
malloced_buffer - location, where the callback should store
either TRUE or FALSE, telling the framework
whether the buffer must be free(3)ed.
The return code is interpreted as follows:
>0 - OK
0 - undefined variable
<0 - error
*/
typedef int (*var_cb_t)(void* context,
const char* varname, size_t name_len,
const char** data, size_t* data_len, size_t* buffer_size);
/*
This structure configures the parser's specials. I think, the fields
are pretty self-explanatory. The only one worth mentioning is
force_expand, which is a boolean. If set to TRUE, variable_expand()
will fail with an error if the lookup callback returns "undefined
variable". If set to FALSE, variable_expand() will copy the
expression that failed verbatimly to the output so that another pass
may expand it.
The comments after each field show the default configuration.
*/
typedef struct
{
char varinit; /* '$' */
char startdelim; /* '{' */
char enddelim; /* '}' */
char escape; /* '\' */
char* namechars; /* 'a-zA-Z0-9_' */
}
var_config_t;
extern const var_config_t var_config_default;
/*
variable_expand() will parse the contents of input for variable
expressions and expand them using the provided lookup callback. The
pointer to the resulting buffer is stored in result, its length in
result_len. The buffer is always terminated by a '\0' byte, which is
not included in the result_len count. The buffer must be free(3)ed
by the caller.
*/
var_rc_t var_expand(const char* input, size_t input_len,
char** result, size_t* result_len,
var_cb_t lookup, void* lookup_context,
const var_config_t* config, int force_expand);
#endif /* !defined(LIB_VARIABLE_EXPAND_H) */
