except.h

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/*
 * Portable Exception Handling for ANSI C.
 * Copyright (C) 1999 Kaz Kylheku <kaz@ashi.footprints.net>
 *
 * Free Software License:
 *
 * All rights are reserved by the author, with the following exceptions:
 * Permission is granted to freely reproduce and distribute this software,
 * possibly in exchange for a fee, provided that this copyright notice appears
 * intact. Permission is also granted to adapt this software to produce
 * derivative works, as long as the modified versions carry this copyright
 * notice and additional notices stating that the work has been modified.
 * This source code may be translated into executable form and incorporated
 * into proprietary software; there is no requirement for such software to
 * contain a copyright notice related to this source.
 *
 */
 
#pragma once
#include <glib.h>
#include <setjmp.h>
#include <stdlib.h>
#include <stdarg.h>
#include <assert.h>
#include "ws_symbol_export.h"
#include "ws_attributes.h"
 
#define XCEPT_GROUP_ANY 0
#define XCEPT_CODE_ANY  0
#define XCEPT_BAD_ALLOC 1
 
#ifdef __cplusplus
extern "C" {
#endif
 
enum { except_no_call, 
       except_call     
};
 
 
typedef struct {
    unsigned long except_group; 
    unsigned long except_code;  
} except_id_t;
 
 
typedef struct {
    except_id_t volatile  except_id;      
    const char *volatile  except_message; 
    void       *volatile  except_dyndata; 
} except_t;
 
 
struct except_cleanup {
    void (*except_func)(void *); 
    void  *except_context;       
};
 
 
struct except_catch {
    const except_id_t *except_id;   
    size_t             except_size;  
    except_t           except_obj;   
    jmp_buf            except_jmp;   
};
 
 
enum except_stacktype {
    XCEPT_CLEANUP, 
    XCEPT_CATCHER  
};
 
struct except_stacknode {
    struct except_stacknode *except_down; 
    enum except_stacktype except_type;    
    union {
        struct except_catch *except_catcher;   
        struct except_cleanup *except_cleanup; 
    } except_info;
};
 
/* private functions made external so they can be used in macros */
 
WS_DLL_PUBLIC void except_setup_clean(struct except_stacknode *,
        struct except_cleanup *, void (*)(void *), void *);
 
WS_DLL_PUBLIC void except_setup_try(struct except_stacknode *,
        struct except_catch *, const except_id_t [], size_t);
 
WS_DLL_PUBLIC struct except_stacknode *except_pop(void);
 
/* public interface functions */
WS_DLL_PUBLIC int except_init(void);
 
WS_DLL_PUBLIC void except_deinit(void);
 
WS_DLL_PUBLIC WS_NORETURN void except_rethrow(except_t * except);
 
WS_DLL_PUBLIC WS_NORETURN void except_throw(long group, long code, const char *msg);
 
WS_DLL_PUBLIC WS_NORETURN void except_throwd(long group, long code, const char *msg, void *data);
 
WS_DLL_PUBLIC WS_NORETURN void except_vthrowf(long group, long code, const char *fmt, va_list vl);
 
WS_DLL_PUBLIC WS_NORETURN void except_throwf(long group, long code, const char *fmt, ...)
    G_GNUC_PRINTF(3, 4);
 
WS_DLL_PUBLIC void (*except_unhandled_catcher(void (*new_catcher)(except_t *)))(except_t *);
 
extern unsigned long except_code(except_t *ex);
 
extern unsigned long except_group(except_t *ex);
 
extern const char *except_message(except_t *ex);
 
extern void *except_data(except_t *ex);
 
WS_DLL_PUBLIC void *except_take_data(except_t * ex);
 
WS_DLL_PUBLIC void except_set_allocator(void *(*alloc)(size_t), void (*dealloc)(void *));
 
WS_DLL_PUBLIC void *except_alloc(size_t size);
 
WS_DLL_PUBLIC void except_free(void * ptr);
 
/* Functions to be used in a last resort when things go badly wrong; e.g.,
 * Lua uses setjmp and longjmp for its own error handling, and Lua errors
 * can longjmp past the ENDTRY so that the function that created the current
 * top node has exited and the node (and the jmp_buf) is no longer valid
 * (having been created on the stack) so we can't run the handlers or even
 * traverse the exception stack. It's better to do this than crash.  */
 
const struct except_stacknode *except_get_top(void);
 
void except_set_top(struct except_stacknode *node);
 
#define except_code(E) ((E)->except_id.except_code)
#define except_group(E) ((E)->except_id.except_group)
#define except_message(E) ((E)->except_message)
#define except_data(E) ((E)->except_dyndata)
 
#ifdef __cplusplus
}
#endif
 
/*
 * void except_cleanup_push(void (*)(void *), void *);
 * void except_cleanup_pop(int);
 * void except_checked_cleanup_pop(void (*)(void *), int);
 * void except_try_push(const except_id_t [], size_t, except_t **);
 * void except_try_pop(void);
 */
 
#define except_cleanup_push(F, C)                               \
    {                                                           \
        struct except_stacknode except_sn;                      \
        struct except_cleanup except_cl;                        \
        except_setup_clean(&except_sn, &except_cl, F, C)
 
#define except_cleanup_pop(E)                                   \
        except_pop();                                           \
        if (E)                                                  \
            except_cl.except_func(except_cl.except_context);    \
    }
 
#define except_checked_cleanup_pop(F, E)                        \
            except_pop();                                       \
        assert (except_cl.except_func == (F));                  \
        if (E)                                                  \
            except_cl.except_func(except_cl.except_context);    \
    }
 
 
/* --- Variants to allow nesting of except_cleanup_push w/o "shadowing" variables */
#define except_cleanup_push_pfx(pfx, F, C)                      \
    {                                                           \
        struct except_stacknode pfx##_except_sn;                \
        struct except_cleanup pfx##_except_cl;                  \
        except_setup_clean(&pfx##_except_sn, &pfx##_except_cl, F, C)
 
#define except_cleanup_pop_pfx(pfx, E)                          \
        except_pop();                                           \
        if (E)                                                  \
            pfx##_except_cl.except_func(pfx##_except_cl.except_context);\
    }
 
#define except_checked_cleanup_pop_pfx(pfx, F, E)               \
            except_pop();                                       \
        assert (pfx##_except_cl.except_func == (F));            \
        if (E)                                                  \
            pfx##_except_cl.except_func(pfx##_except_cl.except_context);\
    }
/* ---------- */
 
 
#define except_try_push(ID, NUM, PPE)                           \
     {                                                          \
        struct except_stacknode except_sn;                      \
        struct except_catch except_ch;                          \
        except_setup_try(&except_sn, &except_ch, ID, NUM);      \
        if (setjmp(except_ch.except_jmp))                       \
            *(PPE) = &except_ch.except_obj;                     \
        else                                                    \
            *(PPE) = 0
 
#define except_try_pop()                                        \
        except_free(except_ch.except_obj.except_dyndata);       \
        except_pop();                                           \
    }
 
/*
 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 4
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * vi: set shiftwidth=4 tabstop=8 expandtab:
 * :indentSize=4:tabSize=8:noTabs=true:
 */