Annotation of parser3/src/include/pa_pool.h, revision 1.34
1.34 ! paf 1: /** @file
1.27 paf 2: Parser
3: Copyright (c) 2001 ArtLebedev Group (http://www.artlebedev.com)
1.28 paf 4: Author: Alexander Petrosyan <paf@design.ru> (http://design.ru/paf)
1.27 paf 5:
1.34 ! paf 6: $Id: pa_pool.h,v 1.33 2001/03/14 08:50:01 paf Exp $
1.1 paf 7: */
8:
9: #ifndef PA_POOL_H
10: #define PA_POOL_H
11:
12: #include <stddef.h>
13:
1.21 paf 14: class Exception;
1.25 paf 15: class Temp_exception;
1.1 paf 16:
1.34 ! paf 17: /** @brief
! 18: Pool mechanizm allows users not to free up allocated memory,
! 19: leaving that problem to 'pools'.
! 20:
! 21: Also holds Exception object, which can be temporary set using
! 22: Temp_exception auto-object.
! 23: */
! 24:
1.1 paf 25: class Pool {
1.25 paf 26: friend Temp_exception;
1.1 paf 27: public:
1.18 paf 28:
1.31 paf 29: Pool() : fexception(0) {}
1.18 paf 30: ~Pool() {}
31:
1.34 ! paf 32: /// current exception object of the pool
1.31 paf 33: Exception& exception() const { return *fexception; }
1.18 paf 34:
1.34 ! paf 35: /// allocates some bytes on pool
1.18 paf 36: void *malloc(size_t size) {
37: return check(real_malloc(size), size);
38: }
1.34 ! paf 39: /// allocates some bytes clearing them with zeros
1.18 paf 40: void *calloc(size_t size) {
41: return check(real_calloc(size), size);
42: }
1.8 paf 43:
1.23 paf 44: private: // implementation defined
1.18 paf 45:
1.20 paf 46: void *real_malloc(size_t size);
47: void *real_calloc(size_t size);
1.17 paf 48:
1.23 paf 49: private:
1.17 paf 50:
1.34 ! paf 51: /// checks whether mem allocated OK. throws exception otherwise
1.23 paf 52: void *check(void *ptr, size_t size) {
53: if(ptr)
54: return ptr;
55:
56: fail(size);
57:
58: // never reached
59: return 0;
60: }
1.34 ! paf 61: /// throws proper exception
1.23 paf 62: void fail(size_t size) const;
63:
1.34 ! paf 64: private: // exception handling
1.17 paf 65:
1.23 paf 66: // exception replacement mechanism is 'protected' from direct usage
1.34 ! paf 67: // Temp_exception object enforces paired set/restore
1.23 paf 68: Exception *set_exception(Exception *e){
1.31 paf 69: Exception *r=fexception;
70: fexception=e;
1.23 paf 71: return r;
72: }
73: void restore_exception(Exception *e) {
1.31 paf 74: fexception=e;
1.23 paf 75: }
76:
77: private:
78:
79: // current request's exception object
1.31 paf 80: Exception *fexception;
1.17 paf 81:
1.8 paf 82: private: //disabled
83:
1.18 paf 84: // Pool(const Pool&) {}
1.16 paf 85: Pool& operator = (const Pool&) { return *this; }
1.21 paf 86: };
87:
1.34 ! paf 88: /** @brief
! 89: Base for all classes that are allocated in 'pools'.
! 90:
! 91: Holds Pool object. Contains useful wrappers to it's methods.
! 92: */
1.21 paf 93: class Pooled {
1.23 paf 94: // the pool i'm allocated on
95: Pool& fpool;
1.21 paf 96: public:
1.23 paf 97:
1.21 paf 98: static void *operator new(size_t size, Pool& apool) {
99: return apool.malloc(size);
100: }
101:
1.23 paf 102: Pooled(Pool& apool) : fpool(apool) {
103: }
104:
1.34 ! paf 105: /// my pool
1.22 paf 106: Pool& pool() const { return fpool; }
1.21 paf 107:
1.34 ! paf 108: /// useful wrapper around pool
1.23 paf 109: void *malloc(size_t size) const { return fpool.malloc(size); }
1.34 ! paf 110: /// useful wrapper around pool
1.23 paf 111: void *calloc(size_t size) const { return fpool.calloc(size); }
1.34 ! paf 112: /// useful wrapper around pool
1.31 paf 113: Exception& exception() const { return fpool.exception(); }
1.23 paf 114: };
1.34 ! paf 115: /// useful macro for creating objects on current Pooled object Pooled::pool()
1.23 paf 116: #define NEW new(pool())
117:
1.34 ! paf 118: /** @brief
! 119: Auto-object used for temporary changing Pool's exception().
! 120:
! 121: Use by with these macros:
! 122: \code
! 123: TRY {
! 124: ...
! 125: if(?)
! 126: THROW(?);
! 127: ...;
! 128: } CATCH(e) {
! 129: code, using e fields
! 130: e.comment()
! 131: }
! 132: END_CATCH
! 133: \endcode
! 134: */
1.25 paf 135: class Temp_exception {
1.29 paf 136: Pool& fpool;
1.23 paf 137: Exception *saved_exception;
138: public:
1.25 paf 139: Temp_exception(Pool& apool, Exception& exception) :
1.29 paf 140: fpool(apool),
1.23 paf 141: saved_exception(apool.set_exception(&exception)) {
142: }
1.25 paf 143: ~Temp_exception() {
1.29 paf 144: fpool.restore_exception(saved_exception);
1.23 paf 145: }
1.1 paf 146: };
1.23 paf 147:
1.33 paf 148: #define XTRY(pool) \
1.24 paf 149: { \
150: Exception temp_exception; \
1.33 paf 151: Temp_exception le(pool, temp_exception); \
1.24 paf 152: if(setjmp(temp_exception.mark)==0)
1.31 paf 153:
1.33 paf 154: #define XTHROW(exception) exception._throw
155: #define XCATCH(e) \
1.24 paf 156: else{ \
157: Exception& e=temp_exception;
1.31 paf 158:
1.33 paf 159: #define XEND_CATCH \
1.24 paf 160: } \
161: }
1.33 paf 162:
1.34 ! paf 163: //@{
! 164: /// @see Temp_exception
1.33 paf 165: #define TRY XTRY(pool())
166: #define THROW XTHROW(exception())
167: #define CATCH(e) XCATCH(e)
168: #define END_CATCH XEND_CATCH
169:
170: #define PTRY XTRY(pool)
171: #define PTHROW XTHROW(pool.exception())
172: #define PCATCH(e) XCATCH(e)
173: #define PEND_CATCH XEND_CATCH
174:
175: #define RTHROW XTHROW(r.pool().exception())
1.34 ! paf 176: //@}
1.1 paf 177:
178: #endif
E-mail: