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#ifndef __EXCEPTIONS_H__
#define __EXCEPTIONS_H__
#ifndef XCEPT_H
#include "except.h"
#endif
/* Ethereal has only one exception group, to make these macros simple */
#define XCEPT_GROUP_ETHEREAL 1
/* Ethereal's exceptions */
#define BoundsError 1 /* Index is out of range */
#define ReportedBoundsError 2 /* Index is beyond reported length (not cap_len) */
/* Usage:
*
* TRY {
* code;
* }
*
* CATCH(exception) {
* code;
* }
*
* CATCH2(exception1, exception2) {
* code;
* }
*
* CATCH_ALL {
* code;
* }
*
* FINALLY {
* code;
* }
*
* ENDTRY;
*
* ********* Never use 'goto' or 'return' inside the TRY, CATCH, CATCH_ALL,
* ********* or FINALLY blocks. Execution must proceed through ENDTRY before
* ********* branching out.
*
* This is really something like:
*
* {
* x = setjmp()
* if (x == 0) {
* <TRY code>
* }
* else if (x == 1) {
* <CATCH(1) code>
* }
* else if (x == 2) {
* <CATCH(2) code>
* }
* else if (x == 3 || x == 4) {
* <CATCH2(3,4) code>
* }
* else {
* <CATCH_ALL code> {
* }
* <FINALLY code>
* }<ENDTRY tag>
*
* All CATCH's must precede a CATCH_ALL.
* FINALLY must occur after any CATCH or CATCH_ALL.
* ENDTRY marks the end of the TRY code.
* TRY and ENDTRY are the mandatory parts of a TRY block.
* CATCH, CATCH_ALL, and FINALLY are all optional (although
* you'll probably use at least one, otherwise why "TRY"?)
*
* GET_MESSAGE returns string ptr to exception message
* when exception is thrown via THROW_MESSAGE()
*
* To throw/raise an exception.
*
* THROW(exception)
* RETHROW rethrow the caught exception
*
* A cleanup callback is a function called in case an exception occurs
* and is not caught. It should be used to free any dynamically-allocated data.
* A pop or call_and_pop should occur at the same statement-nesting level
* as the push.
*
* CLEANUP_CB_PUSH(func, data)
* CLEANUP_CB_POP
* CLEANUP_CB_CALL_AND_POP
*/
#define TRY \
{\
except_t *exc; \
static const except_id_t catch_spec[] = { \
{ XCEPT_GROUP_ETHEREAL, XCEPT_CODE_ANY } }; \
except_try_push(catch_spec, 1, &exc); \
if (exc == 0) { \
/* user's code goes here */
#define ENDTRY \
} \
except_try_pop();\
}
#define CATCH(x) \
} \
else if (exc->except_id.except_code == (x)) { \
/* user's code goes here */
#define CATCH2(x,y) \
} \
else if (exc->except_id.except_code == (x) || exc->except_id.except_code == (y)) { \
/* user's code goes here */
#define CATCH_ALL \
} \
else { \
/* user's code goes here */
#define FINALLY \
} \
{ \
/* user's code goes here */
#define THROW(x) \
except_throw(XCEPT_GROUP_ETHEREAL, (x), "XCEPT_GROUP_ETHEREAL")
#define THROW_MESSAGE(x, y) \
except_throw(XCEPT_GROUP_ETHEREAL, (x), (y))
#define GET_MESSAGE except_message(exc)
#define RETHROW except_rethrow(exc)
#define CLEANUP_CB_PUSH(x,y) except_cleanup_push((x),(y)
#define CLEANUP_CB_POP except_cleanup_push(0)
#define CLEANUP_CB_CALL_AND_POP except_cleanup_push(1)
#endif /* __EXCEPTIONS_H__ */
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