diff --git src/ioc/db/dbAccess.c src/ioc/db/dbAccess.c --- src/ioc/db/dbAccess.c +++ src/ioc/db/dbAccess.c @@ -738,28 +738,34 @@ static long getLinkValue(DBADDR *paddr, short dbrType, { dbCommon *precord = paddr->precord; dbFldDes *pfldDes = paddr->pfldDes; + /* size of pbuf storage in bytes, including space for trailing nil */ int maxlen; DBENTRY dbEntry; long status; + long nReq = nRequest ? *nRequest : 1; + + /* dbFindRecord() below will always succeed as we have a + * valid DBADDR, so no point to check again. + * Request for zero elements always succeeds + */ + if(!nReq) + return 0; switch (dbrType) { case DBR_STRING: - maxlen = MAX_STRING_SIZE - 1; - if (nRequest && *nRequest > 1) *nRequest = 1; + maxlen = MAX_STRING_SIZE; + nReq = 1; break; case DBR_DOUBLE: /* Needed for dbCa links */ - if (nRequest && *nRequest) *nRequest = 1; + if (nRequest) *nRequest = 1; *(double *)pbuf = epicsNAN; return 0; case DBR_CHAR: case DBR_UCHAR: - if (nRequest && *nRequest > 0) { - maxlen = *nRequest - 1; - break; - } - /* else fall through ... */ + maxlen = nReq; + break; default: return S_db_badDbrtype; } @@ -768,10 +774,13 @@ static long getLinkValue(DBADDR *paddr, short dbrType, status = dbFindRecord(&dbEntry, precord->name); if (!status) status = dbFindField(&dbEntry, pfldDes->name); if (!status) { - char *rtnString = dbGetString(&dbEntry); + const char *rtnString = dbGetString(&dbEntry); - strncpy(pbuf, rtnString, --maxlen); - pbuf[maxlen] = 0; + strncpy(pbuf, rtnString, maxlen-1); + pbuf[maxlen-1] = 0; + if(dbrType!=DBR_STRING) + nReq = strlen(pbuf)+1; + if(nRequest) *nRequest = nReq; } dbFinishEntry(&dbEntry); return status; @@ -781,28 +790,31 @@ static long getAttrValue(DBADDR *paddr, short dbrType, char *pbuf, long *nRequest) { int maxlen; + long nReq = nRequest ? *nRequest : 1; if (!paddr->pfield) return S_db_badField; switch (dbrType) { case DBR_STRING: - maxlen = MAX_STRING_SIZE - 1; - if (nRequest && *nRequest > 1) *nRequest = 1; + maxlen = MAX_STRING_SIZE; + nReq = 1; break; case DBR_CHAR: case DBR_UCHAR: - if (nRequest && *nRequest > 0) { - maxlen = *nRequest - 1; - break; - } + maxlen = nReq; + break; + /* else fall through ... */ default: return S_db_badDbrtype; } - strncpy(pbuf, paddr->pfield, --maxlen); - pbuf[maxlen] = 0; + strncpy(pbuf, paddr->pfield, maxlen-1); + pbuf[maxlen-1] = 0; + if(dbrType!=DBR_STRING) + nReq = strlen(pbuf)+1; + if(nRequest) *nRequest = nReq; return 0; } @@ -930,6 +942,15 @@ long dbGet(DBADDR *paddr, short dbrType, localAddr.pfield = (char *) pfl->u.r.field; status = convert(&localAddr, pbuf, n, capacity, offset); } + + if(!status && dbrType==DBF_CHAR && nRequest && + paddr->pfldDes && paddr->pfldDes->field_type==DBF_STRING) + { + /* long string ensure nil and truncate to actual length */ + long nReq = *nRequest; + pbuf[nReq-1] = '\0'; + *nRequest = strlen(pbuf)+1; + } } done: paddr->pfield = pfieldsave;