runtime/obj-types.h - main - githubmirror/rsyslog

runtime/obj-types.h
434 строки21 KB
Rainer Gerhards
build: normalize object prototypes and remove decl noise
07 фев 2026, 13:32
07 фев 2026, 13:3263a233a
/* Some type definitions and macros for the obj object.
 * I needed to move them out of the main obj.h, because obj.h's
 * prototypes use other data types. However, their .h's rely
 * on some of the obj.h data types and macros. So I needed to break
 * that loop somehow and I've done that by moving the typedefs
 * into this file here.
 *
 * Copyright 2008-2026 Rainer Gerhards and Adiscon GmbH.
 *
 * This file is part of the rsyslog runtime library.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *       -or-
 *       see COPYING.ASL20 in the source distribution
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef OBJ_TYPES_H_INCLUDED
#define OBJ_TYPES_H_INCLUDED

#include "stringbuf.h"
#include "syslogd-types.h"
#include "atomic.h"

/* property types for obj[De]Serialize() */
typedef enum {
    PROPTYPE_NONE = 0, /* currently no value set */
    PROPTYPE_PSZ = 1,
    PROPTYPE_SHORT = 2,
    PROPTYPE_INT = 3,
    PROPTYPE_LONG = 4,
    PROPTYPE_INT64 = 5,
    PROPTYPE_CSTR = 6,
    PROPTYPE_SYSLOGTIME = 7
} propType_t;

typedef unsigned objID_t;

typedef enum { /* IDs of base methods supported by all objects - used for jump table, so
                * they must start at zero and be incremented. -- rgerhards, 2008-01-04
                */
               objMethod_CONSTRUCT = 0,
               objMethod_DESTRUCT = 1,
               objMethod_SERIALIZE = 2,
               objMethod_DESERIALIZE = 3,
               objMethod_SETPROPERTY = 4,
               objMethod_CONSTRUCTION_FINALIZER = 5,
               objMethod_GETSEVERITY = 6,
               objMethod_DEBUGPRINT = 7
} objMethod_t;
#define OBJ_NUM_METHODS 8 /* must be updated to contain the max number of methods supported */


/* the base data type for interfaces
 * This MUST be in sync with the ifBEGIN macro
 */
struct interface_s {
    int ifVersion; /* must be set to version requested */
    int ifIsLoaded;
    /* is the interface loaded? (0-no, 1-yes, 2-load failed; if not 1, functions can NOT be called! */
};


struct objInfo_s {
    uchar *pszID; /* the object ID as a string */
    size_t lenID; /* length of the ID string */
    int iObjVers;
    uchar *pszName;
    rsRetVal (*objMethods[OBJ_NUM_METHODS])(void *, ...);
    rsRetVal (*QueryIF)(interface_t *);
    struct modInfo_s *pModInfo;
};


struct obj_s { /* the dummy struct that each derived class can be casted to */
    objInfo_t *pObjInfo;
#ifndef NDEBUG /* this means if debug... */
    unsigned int iObjCooCKiE; /* must always be 0xBADEFEE for a valid object */
#endif
    uchar *pszName; /* the name of *this* specific object instance */
};


/* macros which must be gloablly-visible (because they are used during definition of
 * other objects.
 */
#ifndef NDEBUG /* this means if debug... */
    #include <string.h>
    #define BEGINobjInstance obj_t objData
    #define ISOBJ_assert(pObj)                                                       \
        do {                                                                         \
            assert((pObj) != NULL);                                                  \
            assert((unsigned)((obj_t *)(pObj))->iObjCooCKiE == (unsigned)0xBADEFEE); \
        } while (0);
    #define ISOBJ_TYPE_assert(pObj, objType)                                                                           \
        do {                                                                                                           \
            assert(pObj != NULL);                                                                                      \
            if (strcmp((char *)(((obj_t *)pObj)->pObjInfo->pszID), #objType)) {                                        \
                dbgprintf(                                                                                             \
                    "%s:%d ISOBJ assert failure: invalid object type, expected '%s' "                                  \
                    "actual '%s', cookie: %X\n",                                                                       \
                    __FILE__, __LINE__, #objType, (((obj_t *)pObj)->pObjInfo->pszID), ((obj_t *)(pObj))->iObjCooCKiE); \
                fprintf(stderr,                                                                                        \
                        "%s:%d ISOBJ assert failure: invalid object type, expected '%s' "                              \
                        "actual '%s', cookie: %X\n",                                                                   \
                        __FILE__, __LINE__, #objType, (((obj_t *)pObj)->pObjInfo->pszID),                              \
                        ((obj_t *)(pObj))->iObjCooCKiE);                                                               \
                fflush(stderr);                                                                                        \
                assert(!strcmp((char *)(((obj_t *)pObj)->pObjInfo->pszID), #objType));                                 \
            }                                                                                                          \
            assert((unsigned)((obj_t *)(pObj))->iObjCooCKiE == (unsigned)0xBADEFEE);                                   \
        } while (0)
    /* now the same for pointers to "regular" objects (like wrkrInstanceData) */
    #define PTR_ASSERT_DEF unsigned int _Assert_type;
    #define PTR_ASSERT_SET_TYPE(_ptr, _type) _ptr->_Assert_type = _type
    #define PTR_ASSERT_CHK(_ptr, _type)                                             \
        do {                                                                        \
            assert(_ptr != NULL);                                                   \
            if (_ptr->_Assert_type != _type) {                                      \
                dbgprintf(                                                          \
                    "%s:%d PTR_ASSERT_CHECK failure: invalid pointer type %x, "     \
                    "expected %x\n",                                                \
                    __FILE__, __LINE__, _ptr->_Assert_type, _type);                 \
                fprintf(stderr,                                                     \
                        "%s:%d PTR_ASSERT_CHECK failure: invalid pointer type %x, " \
                        "expected %x\n",                                            \
                        __FILE__, __LINE__, _ptr->_Assert_type, _type);             \
                assert(_ptr->_Assert_type == _type);                                \
            }                                                                       \
        } while (0)
#else /* non-debug mode, no checks but much faster */
    #define BEGINobjInstance obj_t objData
    #define ISOBJ_TYPE_assert(pObj, objType)
    #define ISOBJ_assert(pObj)

    #define PTR_ASSERT_DEF
    #define PTR_ASSERT_SET_TYPE(_ptr, _type)
    #define PTR_ASSERT_CHK(_ptr, _type)
#endif

/* a set method for *very simple* object accesses. Note that this does
 * NOT conform to the standard calling conventions and should be
 * used only if actually nothing can go wrong! -- rgerhards, 2008-04-17
 */
#define DEFpropGetMeth(obj, prop, dataType) \
    dataType obj##Get##prop(void) {         \
        return pThis->prop = pVal;          \
    }

#define DEFpropSetMethPTR(obj, prop, dataType)                \
    rsRetVal obj##Set##prop(obj##_t *pThis, dataType *pVal) { \
        pThis->prop = pVal;                                   \
        return RS_RET_OK;                                     \
    }
#define PROTOTYPEpropSetMethPTR(obj, prop, dataType) rsRetVal obj##Set##prop(obj##_t *pThis, dataType *)
#define DEFpropSetMethFP(obj, prop, dataType)           \
    rsRetVal obj##Set##prop(obj##_t *pThis, dataType) { \
        pThis->prop = pVal;                             \
        return RS_RET_OK;                               \
    }
#define PROTOTYPEpropSetMethFP(obj, prop, dataType) rsRetVal obj##Set##prop(obj##_t *pThis, dataType)
#define DEFpropSetMeth(obj, prop, dataType)                  \
    rsRetVal obj##Set##prop(obj##_t *pThis, dataType pVal) { \
        pThis->prop = pVal;                                  \
        return RS_RET_OK;                                    \
    }
#define PROTOTYPEpropSetMeth(obj, prop, dataType) rsRetVal obj##Set##prop(obj##_t *pThis, dataType pVal)
#define INTERFACEpropSetMeth(obj, prop, dataType) rsRetVal (*Set##prop)(obj##_t * pThis, dataType)
/* class initializer */
#define PROTOTYPEObjClassInit(objName) rsRetVal objName##ClassInit(struct modInfo_s *)
/* below: objName must be the object name (e.g. vm, strm, ...) and ISCORE must be
 * 1 if the module is a statically linked core module and 0 if it is a
 * dynamically loaded one. -- rgerhards, 2008-02-29
 */
#define OBJ_IS_CORE_MODULE 1 /* This should better be renamed to something like "OBJ_IS_NOT_LIBHEAD" or so... ;) */
#define OBJ_IS_LOADABLE_MODULE 0
#define BEGINObjClassInit(objName, objVers, objType)                                                                 \
    rsRetVal objName##ClassInit(struct modInfo_s *pModInfo) {                                                        \
        DEFiRet;                                                                                                     \
        if (objType == OBJ_IS_CORE_MODULE) { /* are we a core module? */                                             \
            CHKiRet(objGetObjInterface(&obj)); /* this provides the root pointer for all other queries */            \
        }                                                                                                            \
        CHKiRet(obj.InfoConstruct(&pObjInfoOBJ, (uchar *)#objName, objVers, (rsRetVal(*)(void *))objName##Construct, \
                                  (rsRetVal(*)(void *))objName##Destruct,                                            \
                                  (rsRetVal(*)(interface_t *))objName##QueryInterface, pModInfo));

#define ENDObjClassInit(objName)                            \
    iRet = obj.RegisterObj((uchar *)#objName, pObjInfoOBJ); \
finalize_it:                                                \
    RETiRet;                                                \
    }

/* ... and now the same for abstract classes.
 * TODO: consolidate the two -- rgerhards, 2008-02-29
 */
#define BEGINAbstractObjClassInit(objName, objVers, objType)                                              \
    rsRetVal objName##ClassInit(struct modInfo_s *pModInfo) {                                             \
        DEFiRet;                                                                                          \
        if (objType == OBJ_IS_CORE_MODULE) { /* are we a core module? */                                  \
            CHKiRet(objGetObjInterface(&obj)); /* this provides the root pointer for all other queries */ \
        }                                                                                                 \
        CHKiRet(obj.InfoConstruct(&pObjInfoOBJ, (uchar *)#objName, objVers, NULL, NULL,                   \
                                  (rsRetVal(*)(interface_t *))objName##QueryInterface, pModInfo));

#define ENDObjClassInit(objName)                            \
    iRet = obj.RegisterObj((uchar *)#objName, pObjInfoOBJ); \
finalize_it:                                                \
    RETiRet;                                                \
    }


/* now come the class exit. This is to be called immediately before the class is
 * unloaded (actual unload for plugins, program termination for core modules)
 * gerhards, 2008-03-10
 */
#define PROTOTYPEObjClassExit(objName) rsRetVal objName##ClassExit(void)
#define BEGINObjClassExit(objName, objType) \
    rsRetVal objName##ClassExit(void) {     \
        DEFiRet;

#define CODESTARTObjClassExit(objName)

#define ENDObjClassExit(objName)                 \
    iRet = obj.UnregisterObj((uchar *)#objName); \
    RETiRet;                                     \
    }

/* this defines both the constructor and initializer
 * rgerhards, 2008-01-10
 */
#define PROTOTYPEobjConstruct(obj) rsRetVal obj##Construct(obj##_t **ppThis)
#define BEGINobjConstruct(obj)                                                 \
    static rsRetVal obj##Initialize(obj##_t __attribute__((unused)) * pThis) { \
        DEFiRet;

#define ENDobjConstruct(obj)                                           \
    /* use finalize_it: before calling the macro (if you need it)! */  \
    RETiRet;                                                           \
    }                                                                  \
    rsRetVal obj##Construct(obj##_t **ppThis) {                        \
        DEFiRet;                                                       \
        obj##_t *pThis;                                                \
                                                                       \
        assert(ppThis != NULL);                                        \
                                                                       \
        if ((pThis = (obj##_t *)calloc(1, sizeof(obj##_t))) == NULL) { \
            ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);                      \
        }                                                              \
        objConstructSetObjInfo(pThis);                                 \
                                                                       \
        obj##Initialize(pThis);                                        \
                                                                       \
    finalize_it:                                                       \
        OBJCONSTRUCT_CHECK_SUCCESS_AND_CLEANUP                         \
        RETiRet;                                                       \
    }


/* this defines the destructor. The important point is that the base object
 * destructor is called. The upper-level class shall destruct all of its
 * properties, but not the instance itself. This is freed here by the
 * framework (we need an intact pointer because we need to free the
 * obj_t structures inside it). A pointer to the object pointer must be
 * parse, because it is re-set to NULL (this, for example, is important in
 * cancellation handlers). The object pointer is always named pThis.
 * The object is always freed, even if there is some error while
 * Cancellation is blocked during destructors, as this could have fatal
 * side-effects. However, this also means the upper-level object should
 * not perform any lengthy processing.
 * IMPORTANT: if the upper level object requires some situations where the
 * object shall not be destructed (e.g. via reference counting), then
 * it shall set pThis to NULL, which prevents destruction of the
 * object.
 * processing.
 * rgerhards, 2008-01-30
 */
#define PROTOTYPEobjDestruct(OBJ) rsRetVal OBJ##Destruct(OBJ##_t __attribute__((unused)) * *ppThis)
/* note: we generate a prototype in any case, as this does not hurt but
 * many modules otherwise seem to miss one, which generates compiler
 * warnings.
 */
#define BEGINobjDestruct(OBJ)                                           \
    rsRetVal OBJ##Destruct(OBJ##_t __attribute__((unused)) * *ppThis) { \
        DEFiRet;                                                        \
        OBJ##_t *pThis;

#define CODESTARTobjDestruct(OBJ) \
    assert(ppThis != NULL);       \
    pThis = *ppThis;              \
    ISOBJ_TYPE_assert(pThis, OBJ);

/* note: there was a long-time bug in the macro below that lead to *ppThis = NULL
 * only when the object was actually destructed. I discovered this issue during
 * introduction of the pRcvFrom property in smsg_t, but it potentially had other
 * effects, too. I am not sure if some experienced instability resulted from this
 * bug OR if its fix will cause harm to so-far "correctly" running code. The later
 * may very well be. Thus I will change it only for the current branch and also
 * the beta, but not in all old builds. Let's see how things evolve.
 * rgerhards, 2009-06-30
 */
#define ENDobjDestruct(OBJ)                             \
    goto finalize_it; /* prevent compiler warning ;) */ \
    /* no more code here! */                            \
finalize_it:                                            \
    if (pThis != NULL) {                                \
        obj.DestructObjSelf((obj_t *)pThis);            \
        free(pThis);                                    \
    }                                                   \
    *ppThis = NULL;                                     \
    RETiRet;                                            \
    }


/* this defines the debug print entry point. DebugPrint is optional. If
 * it is provided, the object should output some meaningful information
 * via the debug system.
 * rgerhards, 2008-02-20
 */
#define PROTOTYPEObjDebugPrint(obj) rsRetVal obj##DebugPrint(obj##_t *pThis)
#define INTERFACEObjDebugPrint(obj) rsRetVal (*DebugPrint)(obj##_t * pThis)
#define BEGINobjDebugPrint(obj)                                         \
    rsRetVal obj##DebugPrint(obj##_t __attribute__((unused)) * pThis) { \
        DEFiRet;

#define CODESTARTobjDebugPrint(obj) \
    assert(pThis != NULL);          \
    ISOBJ_TYPE_assert(pThis, obj);

#define ENDobjDebugPrint(obj) \
    RETiRet;                  \
    }

/* ------------------------------ object loader system ------------------------------ *
 * The following code builds a dynamic object loader system. The
 * root idea is that all objects are dynamically loadable,
 * which is necessary to get a clean plug-in interface where every plugin can access
 * rsyslog's rich object model via simple and quite portable methods.
 *
 * To do so, each object defines one or more interfaces. They are essentially structures
 * with function (method) pointers. Anyone interested in calling an object must first
 * obtain the interface and can then call through it.
 *
 * The interface data type must always be called <obj>_if_t, as this is expected
 * by the macros. Having consitent naming is also easier for the programmer. By default,
 * macros create a static variable named like the object in each calling objects
 * static data block.
 *
 * rgerhards, 2008-02-21 (initial implementation), 2008-04-17 (update of this note)
 */

/* this defines the QueryInterface print entry point. Over time, it should be
 * present in all objects.
 */
#define BEGINobjQueryInterface(obj)                 \
    rsRetVal obj##QueryInterface(obj##_if_t *pIf) { \
        DEFiRet;

#define CODESTARTobjQueryInterface(obj) assert(pIf != NULL);

#define ENDobjQueryInterface(obj) \
    RETiRet;                      \
    }

#define PROTOTYPEObjQueryInterface(obj) rsRetVal obj##QueryInterface(obj##_if_t *pIf)


/* the following macros should be used to define interfaces inside the
 * header files.
 */
#define BEGINinterface(obj)     \
    typedef struct obj##_if_s { \
        ifBEGIN /* This MUST always be the first interface member */
#define ENDinterface(obj) \
    }                     \
    obj##_if_t;

/* the following macro is used to get access to an object (not an instance,
 * just the class itself!). It must be called before any of the object's
 * methods can be accessed. The MYLIB part is the name of my library, or NULL if
 * the caller is a core module. Using the right value here is important to get
 * the reference counting correct (object accesses from the same library must
 * not be counted because that would cause a library plugin to never unload, as
 * its ClassExit() entry points are only called if no object is referenced, which
 * would never happen as the library references itself.
 * rgerhards, 2008-03-11
 */
#define CORE_COMPONENT NULL /* use this to indicate this is a core component */
#define DONT_LOAD_LIB NULL /* do not load a library to obtain object interface (currently same as CORE_COMPONENT) */
#define objUse(objName, FILENAME) obj.UseObj(__FILE__, (uchar *)#objName, (uchar *)FILENAME, (void *)&objName)
#define objRelease(objName, FILENAME) obj.ReleaseObj(__FILE__, (uchar *)#objName, (uchar *)FILENAME, (void *)&objName)

/* defines data that must always be present at the very begin of the interface structure */
#define ifBEGIN                                           \
    int ifVersion; /* must be set to version requested */ \
    int ifIsLoaded; /* is the interface loaded? (0-no, 1-yes; if no, functions can NOT be called! */


/* use the following define some place in your static data (suggested right at
 * the beginning
 */
#define DEFobjCurrIf(obj) static obj##_if_t obj = {.ifVersion = obj##CURR_IF_VERSION, .ifIsLoaded = 0};

/* define the prototypes for a class - keep signatures behind PROTOTYPE*
 * macros so interface changes are localized in this file.
 */
#define PROTOTYPEObjBasic(obj)  \
    PROTOTYPEObjClassInit(obj); \
    PROTOTYPEObjClassExit(obj); \
    PROTOTYPEObjQueryInterface(obj)

/* use where typed object ctor/dtor declarations are valid in scope */
#define PROTOTYPEObjFull(obj)   \
    PROTOTYPEObjBasic(obj);     \
    PROTOTYPEobjConstruct(obj); \
    PROTOTYPEobjDestruct(obj)

/* legacy alias kept for broad in-tree compatibility */
#define PROTOTYPEObj(obj) PROTOTYPEObjBasic(obj)

/* ------------------------------ end object loader system ------------------------------ */


#include "modules.h"

#endif /* #ifndef OBJ_TYPES_H_INCLUDED */