Check in the pristine copy of ICU 4.6...

icu46/source/common/uenum.c

+/*
+*******************************************************************************
+*
+*   Copyright (C) 2002-2004, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+*******************************************************************************
+*   file name:  uenum.c
+*   encoding:   US-ASCII
+*   tab size:   8 (not used)
+*   indentation:2
+*
+*   created on: 2002jul08
+*   created by: Vladimir Weinstein
+*/
+
+#include "unicode/putil.h"
+#include "uenumimp.h"
+#include "cmemory.h"
+
+/* Layout of the baseContext buffer. */
+typedef struct {
+    int32_t len;  /* number of bytes available starting at 'data' */
+    char    data; /* actual data starts here */
+} _UEnumBuffer;
+
+/* Extra bytes to allocate in the baseContext buffer. */
+static const int32_t PAD = 8;
+
+/* Return a pointer to the baseContext buffer, possibly allocating
+   or reallocating it if at least 'capacity' bytes are not available. */
+static void* _getBuffer(UEnumeration* en, int32_t capacity) {
+
+    if (en->baseContext != NULL) {
+        if (((_UEnumBuffer*) en->baseContext)->len < capacity) {
+            capacity += PAD;
+            en->baseContext = uprv_realloc(en->baseContext,
+                                           sizeof(int32_t) + capacity);
+            if (en->baseContext == NULL) {
+                return NULL;
+            }
+            ((_UEnumBuffer*) en->baseContext)->len = capacity;
+        }
+    } else {
+        capacity += PAD;
+        en->baseContext = uprv_malloc(sizeof(int32_t) + capacity);
+        if (en->baseContext == NULL) {
+            return NULL;
+        }
+        ((_UEnumBuffer*) en->baseContext)->len = capacity;
+    }
+    
+    return (void*) & ((_UEnumBuffer*) en->baseContext)->data;
+}
+
+U_CAPI void U_EXPORT2
+uenum_close(UEnumeration* en)
+{
+    if (en) {
+        if (en->close != NULL) {
+            if (en->baseContext) {
+                uprv_free(en->baseContext);
+            }
+            en->close(en);
+        } else { /* this seems dangerous, but we better kill the object */
+            uprv_free(en);
+        }
+    }
+}
+
+U_CAPI int32_t U_EXPORT2
+uenum_count(UEnumeration* en, UErrorCode* status)
+{
+    if (!en || U_FAILURE(*status)) {
+        return -1;
+    }
+    if (en->count != NULL) {
+        return en->count(en, status);
+    } else {
+        *status = U_UNSUPPORTED_ERROR;
+        return -1;
+    }
+}
+
+/* Don't call this directly. Only uenum_unext should be calling this. */
+U_CAPI const UChar* U_EXPORT2
+uenum_unextDefault(UEnumeration* en,
+            int32_t* resultLength,
+            UErrorCode* status)
+{
+    UChar *ustr = NULL;
+    int32_t len = 0;
+    if (en->next != NULL) {
+        const char *cstr = en->next(en, &len, status);
+        if (cstr != NULL) {
+            ustr = (UChar*) _getBuffer(en, (len+1) * sizeof(UChar));
+            if (ustr == NULL) {
+                *status = U_MEMORY_ALLOCATION_ERROR;
+            } else {
+                u_charsToUChars(cstr, ustr, len+1);
+            }
+        }
+    } else {
+        *status = U_UNSUPPORTED_ERROR;
+    }
+    if (resultLength) {
+        *resultLength = len;
+    }
+    return ustr;
+}
+
+/* Don't call this directly. Only uenum_next should be calling this. */
+U_CAPI const char* U_EXPORT2
+uenum_nextDefault(UEnumeration* en,
+            int32_t* resultLength,
+            UErrorCode* status)
+{
+    if (en->uNext != NULL) {
+        char *tempCharVal;
+        const UChar *tempUCharVal = en->uNext(en, resultLength, status);
+        if (tempUCharVal == NULL) {
+            return NULL;
+        }
+        tempCharVal = (char*)
+            _getBuffer(en, (*resultLength+1) * sizeof(char));
+        if (!tempCharVal) {
+            *status = U_MEMORY_ALLOCATION_ERROR;
+            return NULL;
+        }
+        u_UCharsToChars(tempUCharVal, tempCharVal, *resultLength + 1);
+        return tempCharVal;
+    } else {
+        *status = U_UNSUPPORTED_ERROR;
+        return NULL;
+    }
+}
+
+U_CAPI const UChar* U_EXPORT2
+uenum_unext(UEnumeration* en,
+            int32_t* resultLength,
+            UErrorCode* status)
+{
+    if (!en || U_FAILURE(*status)) {
+        return NULL;
+    }
+    if (en->uNext != NULL) {
+        return en->uNext(en, resultLength, status);
+    } else {
+        *status = U_UNSUPPORTED_ERROR;
+        return NULL;
+    }
+}
+
+U_CAPI const char* U_EXPORT2
+uenum_next(UEnumeration* en,
+          int32_t* resultLength,
+          UErrorCode* status)
+{
+    if (!en || U_FAILURE(*status)) {
+        return NULL;
+    }
+    if (en->next != NULL) {
+        return en->next(en, resultLength, status);
+    } else {
+        *status = U_UNSUPPORTED_ERROR;
+        return NULL;
+    }
+}
+
+U_CAPI void U_EXPORT2
+uenum_reset(UEnumeration* en, UErrorCode* status)
+{
+    if (!en || U_FAILURE(*status)) {
+        return;
+    }
+    if (en->reset != NULL) {
+        en->reset(en, status);
+    } else {
+        *status = U_UNSUPPORTED_ERROR;
+    }
+}