Error handling

Error codes and ways to deal with them. More...

Collaboration diagram for Error handling:

Macros
#define	ERR_NAME_PAIR(NAME)   {#NAME, CHEAX_##NAME}
#define	CHEAX_BUILTIN_ERROR_NAMES(var)
#define	cheax_ft(c, pad)   { if (cheax_errno(c) != 0) goto pad; }
	Macro to fall through to a pad in case of an error. More...

Enumerations
enum	{   CHEAX_ENOERR = 0x0000 , CHEAX_EREAD = 0x0001 , CHEAX_EEOF = 0x0002 , CHEAX_EEVAL = 0x0101 ,   CHEAX_ENOSYM = 0x0102 , CHEAX_ESTACK = 0x0103 , CHEAX_ETYPE = 0x0104 , CHEAX_EMATCH = 0x0105 ,   CHEAX_ESTATIC = 0x0106 , CHEAX_EDIVZERO = 0x0107 , CHEAX_EREADONLY = 0x0108 , CHEAX_EWRITEONLY = 0x0109 ,   CHEAX_EEXIST = 0x010A , CHEAX_EVALUE = 0x010B , CHEAX_EOVERFLOW = 0x010C , CHEAX_EINDEX = 0x010D ,   CHEAX_EIO = 0x010E , CHEAX_EAPI = 0x0200 , CHEAX_ENOMEM = 0x0201 , CHEAX_EUSER0 = 0x0400 }
	Pre-defined cheax error codes. More...

Functions
int	cheax_errno (CHEAX *c) CHX_PURE
	Gets the value of the current cheax error code. More...
void	cheax_perror (CHEAX *c, const char *s)
	Prints the current cheax error code and error message. More...
void	cheax_clear_errno (CHEAX *c)
	Sets cheax_errno() to 0. More...
void	cheax_throw (CHEAX *c, int code, struct chx_string *msg)
	Sets cheax_errno() to the given value. More...
void	cheax_throwf (CHEAX *c, int code, const char *fmt,...) CHX_FORMAT(printf
void void	cheax_add_bt (CHEAX *c)
int	cheax_new_error_code (CHEAX *c, const char *name)
	Creates a new error code with a given name. More...
int	cheax_find_error_code (CHEAX *c, const char *name)
	Looks up the value of a named error code. More...

Detailed Description

Error codes and ways to deal with them.

Macro Definition Documentation

ERR_NAME_PAIR

#define ERR_NAME_PAIR

(

NAME

)

{#NAME, CHEAX_##NAME}

CHEAX_BUILTIN_ERROR_NAMES

#define CHEAX_BUILTIN_ERROR_NAMES

(

var

)

Value:

static const struct { const char *name; int code; } var[] = { \
        ERR_NAME_PAIR(ENOERR),                                \
	                                                      \
	ERR_NAME_PAIR(EREAD), ERR_NAME_PAIR(EEOF),            \
	                                                      \
	ERR_NAME_PAIR(EEVAL), ERR_NAME_PAIR(ENOSYM),          \
        ERR_NAME_PAIR(ESTACK), ERR_NAME_PAIR(ETYPE),          \
        ERR_NAME_PAIR(EMATCH), ERR_NAME_PAIR(ESTATIC),        \
        ERR_NAME_PAIR(EDIVZERO), ERR_NAME_PAIR(EREADONLY),    \
        ERR_NAME_PAIR(EWRITEONLY), ERR_NAME_PAIR(EEXIST),     \
        ERR_NAME_PAIR(EVALUE), ERR_NAME_PAIR(EOVERFLOW),      \
        ERR_NAME_PAIR(EINDEX), ERR_NAME_PAIR(EIO),            \
	                                                      \
	ERR_NAME_PAIR(EAPI), ERR_NAME_PAIR(ENOMEM)            \
}

cheax_ft

#define cheax_ft	(		c,
			pad
	)		{ if (cheax_errno(c) != 0) goto pad; }

Macro to fall through to a pad in case of an error.

Jumps to pad if cheax_errno() is not 0. Most commonly used after cheax_eval().

Parameters

pad	Label to jump to in case of an error.

Enumeration Type Documentation

anonymous enum

anonymous enum

Pre-defined cheax error codes.

See also

cheax_errno(), cheax_throw(), cheax_new_error_code()

Enumerator
CHEAX_ENOERR	No error. Equal to 0. See also cheax_clear_errno()
CHEAX_EREAD	Generic read error.
CHEAX_EEOF	Unexpected end-of-file.
CHEAX_EEVAL	Generic eval error
CHEAX_ENOSYM	Symbol not found error.
CHEAX_ESTACK	Stack overflow error.
CHEAX_ETYPE	Invalid type error.
CHEAX_EMATCH	Unable to match expression error.
CHEAX_ESTATIC	Preprocessing failed.
CHEAX_EDIVZERO	Division by zero error.
CHEAX_EREADONLY	Attempted write to read-only symbol error.
CHEAX_EWRITEONLY	Attempted read from write-only symbol error.
CHEAX_EEXIST	Symbol already exists error.
CHEAX_EVALUE	Invalid value error.
CHEAX_EOVERFLOW	Integer overflow error.
CHEAX_EINDEX	Invalid index error.
CHEAX_EIO	IO error.
CHEAX_EAPI	API error. Note Not to be thrown from within cheax code.
CHEAX_ENOMEM	Out-of-memory error. Note Not to be thrown from within cheax code.
CHEAX_EUSER0	First user-defineable error code. See also cheax_new_error_code()

Function Documentation

cheax_errno()

int cheax_errno

(

CHEAX *

c

)

Gets the value of the current cheax error code.

See also

cheax_throw(), cheax_new_error_code(), cheax_ft()

cheax_perror()

void cheax_perror	(	CHEAX *	c,
		const char *	s
	)

Prints the current cheax error code and error message.

Parameters

s	Argument string, will be printed followed by a colon and an error description.

cheax_clear_errno()

void cheax_clear_errno

(

CHEAX *

c

)

Sets cheax_errno() to 0.

See also

cheax_errno()

cheax_throw()

void cheax_throw	(	CHEAX *	c,
		int	code,
		struct chx_string *	msg
	)

Sets cheax_errno() to the given value.

Sets cheax_errno() to CHEAX_EAPI if code is 0.

Parameters

code	Error code.
msg	Error message string or NULL.

See also

cheax_errno(), cheax_clear_errno()

cheax_throwf()

void cheax_throwf	(	CHEAX *	c,
		int	code,
		const char *	fmt,
			...
	)

cheax_add_bt()

void void cheax_add_bt

(

CHEAX *

c

)

cheax_new_error_code()

int cheax_new_error_code	(	CHEAX *	c,
		const char *	name
	)

Creates a new error code with a given name.

Such new error codes can then be thrown with cheax_throw() or from within cheax.

Does not change cheax_errno(), except when name is NULL, in which case it is set to CHEAX_EAPI.

Parameters

name	The error code's name. Used to make the error code available in cheax, and for error reporting by cheax_perror().

Returns

The newly created error code value.

cheax_find_error_code()

int cheax_find_error_code	(	CHEAX *	c,
		const char *	name
	)

Looks up the value of a named error code.

Sets cheax_errno() to CHEAX_EAPI if name is NULL.

Parameters

name	Error code name.

Returns

The error code carrying the given name, or -1 if unsuccessful.