Annotation of parser3/src/include/pa_pool.h, revision 1.37
1.34 paf 1: /** @file
1.36 paf 2: Parser: pool class decl.
3:
1.27 paf 4: Copyright (c) 2001 ArtLebedev Group (http://www.artlebedev.com)
1.36 paf 5:
1.28 paf 6: Author: Alexander Petrosyan <paf@design.ru> (http://design.ru/paf)
1.27 paf 7:
1.37 ! paf 8: $Id: pa_pool.h,v 1.36 2001/03/19 17:42:12 paf Exp $
1.1 paf 9: */
10:
11: #ifndef PA_POOL_H
12: #define PA_POOL_H
13:
14: #include <stddef.h>
15:
1.21 paf 16: class Exception;
1.25 paf 17: class Temp_exception;
1.1 paf 18:
1.35 paf 19: /**
1.34 paf 20: Pool mechanizm allows users not to free up allocated memory,
21: leaving that problem to 'pools'.
22:
23: Also holds Exception object, which can be temporary set using
24: Temp_exception auto-object.
25: */
26:
1.1 paf 27: class Pool {
1.25 paf 28: friend Temp_exception;
1.1 paf 29: public:
1.18 paf 30:
1.31 paf 31: Pool() : fexception(0) {}
1.18 paf 32: ~Pool() {}
33:
1.34 paf 34: /// current exception object of the pool
1.31 paf 35: Exception& exception() const { return *fexception; }
1.18 paf 36:
1.34 paf 37: /// allocates some bytes on pool
1.18 paf 38: void *malloc(size_t size) {
39: return check(real_malloc(size), size);
40: }
1.34 paf 41: /// allocates some bytes clearing them with zeros
1.18 paf 42: void *calloc(size_t size) {
43: return check(real_calloc(size), size);
44: }
1.8 paf 45:
1.23 paf 46: private: // implementation defined
1.18 paf 47:
1.20 paf 48: void *real_malloc(size_t size);
49: void *real_calloc(size_t size);
1.17 paf 50:
1.23 paf 51: private:
1.17 paf 52:
1.34 paf 53: /// checks whether mem allocated OK. throws exception otherwise
1.23 paf 54: void *check(void *ptr, size_t size) {
55: if(ptr)
56: return ptr;
57:
58: fail(size);
59:
60: // never reached
61: return 0;
62: }
1.34 paf 63: /// throws proper exception
1.23 paf 64: void fail(size_t size) const;
65:
1.34 paf 66: private: // exception handling
1.17 paf 67:
1.23 paf 68: // exception replacement mechanism is 'protected' from direct usage
1.34 paf 69: // Temp_exception object enforces paired set/restore
1.23 paf 70: Exception *set_exception(Exception *e){
1.31 paf 71: Exception *r=fexception;
72: fexception=e;
1.23 paf 73: return r;
74: }
75: void restore_exception(Exception *e) {
1.31 paf 76: fexception=e;
1.23 paf 77: }
78:
79: private:
80:
81: // current request's exception object
1.31 paf 82: Exception *fexception;
1.17 paf 83:
1.8 paf 84: private: //disabled
85:
1.18 paf 86: // Pool(const Pool&) {}
1.16 paf 87: Pool& operator = (const Pool&) { return *this; }
1.21 paf 88: };
89:
1.35 paf 90: /**
1.34 paf 91: Base for all classes that are allocated in 'pools'.
92:
93: Holds Pool object. Contains useful wrappers to it's methods.
94: */
1.21 paf 95: class Pooled {
1.23 paf 96: // the pool i'm allocated on
97: Pool& fpool;
1.21 paf 98: public:
1.37 ! paf 99:
! 100: /// the Pooled-sole: Pooled instances can be allocated in Pool rather then on heap
1.21 paf 101: static void *operator new(size_t size, Pool& apool) {
102: return apool.malloc(size);
103: }
104:
1.23 paf 105: Pooled(Pool& apool) : fpool(apool) {
106: }
107:
1.34 paf 108: /// my pool
1.22 paf 109: Pool& pool() const { return fpool; }
1.21 paf 110:
1.34 paf 111: /// useful wrapper around pool
1.23 paf 112: void *malloc(size_t size) const { return fpool.malloc(size); }
1.34 paf 113: /// useful wrapper around pool
1.23 paf 114: void *calloc(size_t size) const { return fpool.calloc(size); }
1.34 paf 115: /// useful wrapper around pool
1.31 paf 116: Exception& exception() const { return fpool.exception(); }
1.23 paf 117: };
1.34 paf 118: /// useful macro for creating objects on current Pooled object Pooled::pool()
1.23 paf 119: #define NEW new(pool())
120:
1.35 paf 121: /**
1.34 paf 122: Auto-object used for temporary changing Pool's exception().
123:
124: Use by with these macros:
125: \code
126: TRY {
127: ...
128: if(?)
129: THROW(?);
130: ...;
131: } CATCH(e) {
132: code, using e fields
133: e.comment()
134: }
135: END_CATCH
136: \endcode
137: */
1.25 paf 138: class Temp_exception {
1.29 paf 139: Pool& fpool;
1.23 paf 140: Exception *saved_exception;
141: public:
1.25 paf 142: Temp_exception(Pool& apool, Exception& exception) :
1.29 paf 143: fpool(apool),
1.23 paf 144: saved_exception(apool.set_exception(&exception)) {
145: }
1.25 paf 146: ~Temp_exception() {
1.29 paf 147: fpool.restore_exception(saved_exception);
1.23 paf 148: }
1.1 paf 149: };
1.23 paf 150:
1.33 paf 151: #define XTRY(pool) \
1.24 paf 152: { \
153: Exception temp_exception; \
1.33 paf 154: Temp_exception le(pool, temp_exception); \
1.24 paf 155: if(setjmp(temp_exception.mark)==0)
1.31 paf 156:
1.33 paf 157: #define XTHROW(exception) exception._throw
158: #define XCATCH(e) \
1.24 paf 159: else{ \
160: Exception& e=temp_exception;
1.31 paf 161:
1.33 paf 162: #define XEND_CATCH \
1.24 paf 163: } \
164: }
1.33 paf 165:
1.34 paf 166: //@{
167: /// @see Temp_exception
1.33 paf 168: #define TRY XTRY(pool())
169: #define THROW XTHROW(exception())
170: #define CATCH(e) XCATCH(e)
171: #define END_CATCH XEND_CATCH
172:
173: #define PTRY XTRY(pool)
174: #define PTHROW XTHROW(pool.exception())
175: #define PCATCH(e) XCATCH(e)
176: #define PEND_CATCH XEND_CATCH
177:
178: #define RTHROW XTHROW(r.pool().exception())
1.34 paf 179: //@}
1.1 paf 180:
181: #endif
E-mail:
![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to pa_pool.h CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [parser3project] / parser3 / src / include