michael@0: /*
michael@0: *******************************************************************************
michael@0: *
michael@0: *   Copyright (C) 2002-2012, International Business Machines
michael@0: *   Corporation and others.  All Rights Reserved.
michael@0: *
michael@0: *******************************************************************************
michael@0: *   file name:  uenum.c
michael@0: *   encoding:   US-ASCII
michael@0: *   tab size:   8 (not used)
michael@0: *   indentation:2
michael@0: *
michael@0: *   created on: 2002jul08
michael@0: *   created by: Vladimir Weinstein
michael@0: */
michael@0: 
michael@0: #include "unicode/putil.h"
michael@0: #include "uenumimp.h"
michael@0: #include "cmemory.h"
michael@0: 
michael@0: /* Layout of the baseContext buffer. */
michael@0: typedef struct {
michael@0:     int32_t len;  /* number of bytes available starting at 'data' */
michael@0:     char    data; /* actual data starts here */
michael@0: } _UEnumBuffer;
michael@0: 
michael@0: /* Extra bytes to allocate in the baseContext buffer. */
michael@0: static const int32_t PAD = 8;
michael@0: 
michael@0: /* Return a pointer to the baseContext buffer, possibly allocating
michael@0:    or reallocating it if at least 'capacity' bytes are not available. */
michael@0: static void* _getBuffer(UEnumeration* en, int32_t capacity) {
michael@0: 
michael@0:     if (en->baseContext != NULL) {
michael@0:         if (((_UEnumBuffer*) en->baseContext)->len < capacity) {
michael@0:             capacity += PAD;
michael@0:             en->baseContext = uprv_realloc(en->baseContext,
michael@0:                                            sizeof(int32_t) + capacity);
michael@0:             if (en->baseContext == NULL) {
michael@0:                 return NULL;
michael@0:             }
michael@0:             ((_UEnumBuffer*) en->baseContext)->len = capacity;
michael@0:         }
michael@0:     } else {
michael@0:         capacity += PAD;
michael@0:         en->baseContext = uprv_malloc(sizeof(int32_t) + capacity);
michael@0:         if (en->baseContext == NULL) {
michael@0:             return NULL;
michael@0:         }
michael@0:         ((_UEnumBuffer*) en->baseContext)->len = capacity;
michael@0:     }
michael@0:     
michael@0:     return (void*) & ((_UEnumBuffer*) en->baseContext)->data;
michael@0: }
michael@0: 
michael@0: U_CAPI void U_EXPORT2
michael@0: uenum_close(UEnumeration* en)
michael@0: {
michael@0:     if (en) {
michael@0:         if (en->close != NULL) {
michael@0:             if (en->baseContext) {
michael@0:                 uprv_free(en->baseContext);
michael@0:             }
michael@0:             en->close(en);
michael@0:         } else { /* this seems dangerous, but we better kill the object */
michael@0:             uprv_free(en);
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: U_CAPI int32_t U_EXPORT2
michael@0: uenum_count(UEnumeration* en, UErrorCode* status)
michael@0: {
michael@0:     if (!en || U_FAILURE(*status)) {
michael@0:         return -1;
michael@0:     }
michael@0:     if (en->count != NULL) {
michael@0:         return en->count(en, status);
michael@0:     } else {
michael@0:         *status = U_UNSUPPORTED_ERROR;
michael@0:         return -1;
michael@0:     }
michael@0: }
michael@0: 
michael@0: /* Don't call this directly. Only uenum_unext should be calling this. */
michael@0: U_CAPI const UChar* U_EXPORT2
michael@0: uenum_unextDefault(UEnumeration* en,
michael@0:             int32_t* resultLength,
michael@0:             UErrorCode* status)
michael@0: {
michael@0:     UChar *ustr = NULL;
michael@0:     int32_t len = 0;
michael@0:     if (en->next != NULL) {
michael@0:         const char *cstr = en->next(en, &len, status);
michael@0:         if (cstr != NULL) {
michael@0:             ustr = (UChar*) _getBuffer(en, (len+1) * sizeof(UChar));
michael@0:             if (ustr == NULL) {
michael@0:                 *status = U_MEMORY_ALLOCATION_ERROR;
michael@0:             } else {
michael@0:                 u_charsToUChars(cstr, ustr, len+1);
michael@0:             }
michael@0:         }
michael@0:     } else {
michael@0:         *status = U_UNSUPPORTED_ERROR;
michael@0:     }
michael@0:     if (resultLength) {
michael@0:         *resultLength = len;
michael@0:     }
michael@0:     return ustr;
michael@0: }
michael@0: 
michael@0: /* Don't call this directly. Only uenum_next should be calling this. */
michael@0: U_CAPI const char* U_EXPORT2
michael@0: uenum_nextDefault(UEnumeration* en,
michael@0:             int32_t* resultLength,
michael@0:             UErrorCode* status)
michael@0: {
michael@0:     if (en->uNext != NULL) {
michael@0:         char *tempCharVal;
michael@0:         const UChar *tempUCharVal = en->uNext(en, resultLength, status);
michael@0:         if (tempUCharVal == NULL) {
michael@0:             return NULL;
michael@0:         }
michael@0:         tempCharVal = (char*)
michael@0:             _getBuffer(en, (*resultLength+1) * sizeof(char));
michael@0:         if (!tempCharVal) {
michael@0:             *status = U_MEMORY_ALLOCATION_ERROR;
michael@0:             return NULL;
michael@0:         }
michael@0:         u_UCharsToChars(tempUCharVal, tempCharVal, *resultLength + 1);
michael@0:         return tempCharVal;
michael@0:     } else {
michael@0:         *status = U_UNSUPPORTED_ERROR;
michael@0:         return NULL;
michael@0:     }
michael@0: }
michael@0: 
michael@0: U_CAPI const UChar* U_EXPORT2
michael@0: uenum_unext(UEnumeration* en,
michael@0:             int32_t* resultLength,
michael@0:             UErrorCode* status)
michael@0: {
michael@0:     if (!en || U_FAILURE(*status)) {
michael@0:         return NULL;
michael@0:     }
michael@0:     if (en->uNext != NULL) {
michael@0:         return en->uNext(en, resultLength, status);
michael@0:     } else {
michael@0:         *status = U_UNSUPPORTED_ERROR;
michael@0:         return NULL;
michael@0:     }
michael@0: }
michael@0: 
michael@0: U_CAPI const char* U_EXPORT2
michael@0: uenum_next(UEnumeration* en,
michael@0:           int32_t* resultLength,
michael@0:           UErrorCode* status)
michael@0: {
michael@0:     if (!en || U_FAILURE(*status)) {
michael@0:         return NULL;
michael@0:     }
michael@0:     if (en->next != NULL) {
michael@0:         if (resultLength != NULL) {
michael@0:             return en->next(en, resultLength, status);
michael@0:         }
michael@0:         else {
michael@0:             int32_t dummyLength=0;
michael@0:             return en->next(en, &dummyLength, status);
michael@0:         }
michael@0:     } else {
michael@0:         *status = U_UNSUPPORTED_ERROR;
michael@0:         return NULL;
michael@0:     }
michael@0: }
michael@0: 
michael@0: U_CAPI void U_EXPORT2
michael@0: uenum_reset(UEnumeration* en, UErrorCode* status)
michael@0: {
michael@0:     if (!en || U_FAILURE(*status)) {
michael@0:         return;
michael@0:     }
michael@0:     if (en->reset != NULL) {
michael@0:         en->reset(en, status);
michael@0:     } else {
michael@0:         *status = U_UNSUPPORTED_ERROR;
michael@0:     }
michael@0: }