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/* except.c -- exception mechanism ($Revision: 1.1.1.1 $) */
#include "es.h"
#include "print.h"
/* globals */
Handler *tophandler = NULL;
Handler *roothandler = NULL;
List *exception = NULL;
Push *pushlist = NULL;
/* pophandler -- remove a handler */
extern void pophandler(Handler *handler) {
assert(tophandler == handler);
assert(handler->rootlist == rootlist);
tophandler = handler->up;
}
/* throw -- raise an exception */
extern noreturn throw(List *e) {
Handler *handler = tophandler;
assert(!gcisblocked());
assert(e != NULL);
assert(handler != NULL);
tophandler = handler->up;
while (pushlist != handler->pushlist) {
rootlist = &pushlist->defnroot;
varpop(pushlist);
}
evaldepth = handler->evaldepth;
#if ASSERTIONS
for (; rootlist != handler->rootlist; rootlist = rootlist->next)
assert(rootlist != NULL);
#else
rootlist = handler->rootlist;
#endif
exception = e;
longjmp(handler->label, 1);
NOTREACHED;
}
/* fail -- pass a user catchable error up the exception chain */
extern noreturn fail VARARGS2(const char *, from, const char *, fmt) {
char *s;
va_list args;
VA_START(args, fmt);
s = strv(fmt, args);
va_end(args);
gcdisable();
Ref(List *, e, mklist(mkstr("error"),
mklist(mkstr((char *) from),
mklist(mkstr(s), NULL))));
while (gcisblocked())
gcenable();
throw(e);
RefEnd(e);
}
/* newchildcatcher -- remove the current handler chain for a new child */
extern void newchildcatcher(void) {
tophandler = roothandler;
}
#if DEBUG_EXCEPTIONS
/* raised -- print exceptions as we climb the exception stack */
extern List *raised(List *e) {
eprint("raised (sp @ %x) %L\n", &e, e, " ");
return e;
}
#endif
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