[apple/icu.git] / icuSources / common / udataswp.c

/*
*******************************************************************************
*
*   Copyright (C) 2003, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
*******************************************************************************
*   file name:  udataswp.c
*   encoding:   US-ASCII
*   tab size:   8 (not used)
*   indentation:4
*
*   created on: 2003jun05
*   created by: Markus W. Scherer
*
*   Definitions for ICU data transformations for different platforms,
*   changing between big- and little-endian data and/or between
*   charset families (ASCII<->EBCDIC).
*/

#include <stdarg.h>
#include "unicode/utypes.h"
#include "unicode/udata.h" /* UDataInfo */
#include "ucmndata.h" /* DataHeader */
#include "cmemory.h"
#include "udataswp.h"

/* swapping primitives ------------------------------------------------------ */

static int32_t U_CALLCONV
uprv_swapArray16(const UDataSwapper *ds,
                 const void *inData, int32_t length, void *outData,
                 UErrorCode *pErrorCode) {
    const uint16_t *p;
    uint16_t *q;
    int32_t count;
    uint16_t x;

    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }
    if(ds==NULL || inData==NULL || length<0 || (length&1)!=0 || outData==NULL) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    /* setup and swapping */
    p=(const uint16_t *)inData;
    q=(uint16_t *)outData;
    count=length/2;
    while(count>0) {
        x=*p++;
        *q++=(uint16_t)((x<<8)|(x>>8));
        --count;
    }

    return length;
}

static int32_t U_CALLCONV
uprv_copyArray16(const UDataSwapper *ds,
                 const void *inData, int32_t length, void *outData,
                 UErrorCode *pErrorCode) {
    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }
    if(ds==NULL || inData==NULL || length<0 || (length&1)!=0 || outData==NULL) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    if(length>0 && inData!=outData) {
        uprv_memcpy(outData, inData, length);
    }
    return length;
}

static int32_t U_CALLCONV
uprv_swapArray32(const UDataSwapper *ds,
                 const void *inData, int32_t length, void *outData,
                 UErrorCode *pErrorCode) {
    const uint32_t *p;
    uint32_t *q;
    int32_t count;
    uint32_t x;

    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }
    if(ds==NULL || inData==NULL || length<0 || (length&3)!=0 || outData==NULL) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    /* setup and swapping */
    p=(const uint32_t *)inData;
    q=(uint32_t *)outData;
    count=length/4;
    while(count>0) {
        x=*p++;
        *q++=(uint32_t)((x<<24)|((x<<8)&0xff0000)|((x>>8)&0xff00)|(x>>24));
        --count;
    }

    return length;
}

static int32_t U_CALLCONV
uprv_copyArray32(const UDataSwapper *ds,
                 const void *inData, int32_t length, void *outData,
                 UErrorCode *pErrorCode) {
    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }
    if(ds==NULL || inData==NULL || length<0 || (length&3)!=0 || outData==NULL) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    if(length>0 && inData!=outData) {
        uprv_memcpy(outData, inData, length);
    }
    return length;
}

static uint16_t U_CALLCONV
uprv_readSwapUInt16(uint16_t x) {
    return (uint16_t)((x<<8)|(x>>8));
}

static uint16_t U_CALLCONV
uprv_readDirectUInt16(uint16_t x) {
    return x;
}

static uint32_t U_CALLCONV
uprv_readSwapUInt32(uint32_t x) {
    return (uint32_t)((x<<24)|((x<<8)&0xff0000)|((x>>8)&0xff00)|(x>>24));
}

static uint32_t U_CALLCONV
uprv_readDirectUInt32(uint32_t x) {
    return x;
}

static void U_CALLCONV
uprv_writeSwapUInt16(uint16_t *p, uint16_t x) {
    *p=(uint16_t)((x<<8)|(x>>8));
}

static void U_CALLCONV
uprv_writeDirectUInt16(uint16_t *p, uint16_t x) {
    *p=x;
}

static void U_CALLCONV
uprv_writeSwapUInt32(uint32_t *p, uint32_t x) {
    *p=(uint32_t)((x<<24)|((x<<8)&0xff0000)|((x>>8)&0xff00)|(x>>24));
}

static void U_CALLCONV
uprv_writeDirectUInt32(uint32_t *p, uint32_t x) {
    *p=x;
}

U_CAPI int16_t U_EXPORT2
udata_readInt16(const UDataSwapper *ds, int16_t x) {
    return (int16_t)ds->readUInt16((uint16_t)x);
}

U_CAPI int32_t U_EXPORT2
udata_readInt32(const UDataSwapper *ds, int32_t x) {
    return (int32_t)ds->readUInt32((uint32_t)x);
}

/**
 * Swap a block of invariant, NUL-terminated strings, but not padding
 * bytes after the last string.
 * @internal
 */
U_CAPI int32_t U_EXPORT2
udata_swapInvStringBlock(const UDataSwapper *ds,
                         const void *inData, int32_t length, void *outData,
                         UErrorCode *pErrorCode) {
    const char *inChars;
    int32_t stringsLength;

    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }
    if(ds==NULL || inData==NULL || length<0 || (length>0 && outData==NULL)) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    /* reduce the strings length to not include bytes after the last NUL */
    inChars=(const char *)inData;
    stringsLength=length;
    while(stringsLength>0 && inChars[stringsLength-1]!=0) {
        --stringsLength;
    }

    /* swap up to the last NUL */
    ds->swapInvChars(ds, inData, stringsLength, outData, pErrorCode);

    /* copy the bytes after the last NUL */
    if(inData!=outData && length>stringsLength) {
        uprv_memcpy((char *)outData+stringsLength, inChars+stringsLength, length-stringsLength);
    }

    /* return the length including padding bytes */
    if(U_SUCCESS(*pErrorCode)) {
        return length;
    } else {
        return 0;
    }
}

U_CAPI void U_EXPORT2
udata_printError(const UDataSwapper *ds,
                 const char *fmt,
                 ...) {
    va_list args;

    if(ds->printError!=NULL) {
        va_start(args, fmt);
        ds->printError(ds->printErrorContext, fmt, args);
        va_end(args);
    }
}

/* swap a data header ------------------------------------------------------- */

U_CAPI int32_t U_EXPORT2
udata_swapDataHeader(const UDataSwapper *ds,
                     const void *inData, int32_t length, void *outData,
                     UErrorCode *pErrorCode) {
    const DataHeader *pHeader;
    uint16_t headerSize, infoSize;

    /* argument checking */
    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }
    if(ds==NULL || inData==NULL || length<-1 || (length>0 && outData==NULL)) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    /* check minimum length and magic bytes */
    pHeader=(const DataHeader *)inData;
    if( (length>=0 && length<sizeof(DataHeader)) ||
        pHeader->dataHeader.magic1!=0xda ||
        pHeader->dataHeader.magic2!=0x27 ||
        pHeader->info.sizeofUChar!=2
    ) {
        udata_printError(ds, "udata_swapDataHeader(): initial bytes do not look like ICU data\n");
        *pErrorCode=U_UNSUPPORTED_ERROR;
        return 0;
    }

    headerSize=ds->readUInt16(pHeader->dataHeader.headerSize);
    infoSize=ds->readUInt16(pHeader->info.size);

    if( headerSize<sizeof(DataHeader) ||
        infoSize<sizeof(UDataInfo) ||
        headerSize<(sizeof(pHeader->dataHeader)+infoSize) ||
        (length>=0 && length<headerSize)
    ) {
        udata_printError(ds, "udata_swapDataHeader(): header size mismatch - headerSize %d infoSize %d length %d\n",
                         headerSize, infoSize, length);
        *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
        return 0;
    }

    if(length>0) {
        DataHeader *outHeader;
        const char *s;
        int32_t maxLength;

        /* Most of the fields are just bytes and need no swapping. */
        if(inData!=outData) {
            uprv_memcpy(outData, inData, headerSize);
        }
        outHeader=(DataHeader *)outData;

        outHeader->info.isBigEndian = ds->outIsBigEndian;
        outHeader->info.charsetFamily = ds->outCharset;

        /* swap headerSize */
        ds->swapArray16(ds, &pHeader->dataHeader.headerSize, 2, &outHeader->dataHeader.headerSize, pErrorCode);

        /* swap UDataInfo size and reservedWord */
        ds->swapArray16(ds, &pHeader->info.size, 4, &outHeader->info.size, pErrorCode);

        /* swap copyright statement after the UDataInfo */
        infoSize+=sizeof(pHeader->dataHeader);
        s=(const char *)inData+infoSize;
        maxLength=headerSize-infoSize;
        /* get the length of the string */
        for(length=0; length<maxLength && s[length]!=0; ++length) {}
        /* swap the string contents */
        ds->swapInvChars(ds, s, length, (char *)outData+infoSize, pErrorCode);
    }

    return headerSize;
}

/* API functions ------------------------------------------------------------ */

U_CAPI UDataSwapper * U_EXPORT2
udata_openSwapper(UBool inIsBigEndian, uint8_t inCharset,
                  UBool outIsBigEndian, uint8_t outCharset,
                  UErrorCode *pErrorCode) {
    UDataSwapper *swapper;

    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return NULL;
    }
    if(inCharset>U_EBCDIC_FAMILY || outCharset>U_EBCDIC_FAMILY) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return NULL;
    }

    /* allocate the swapper */
    swapper=uprv_malloc(sizeof(UDataSwapper));
    if(swapper==NULL) {
        *pErrorCode=U_MEMORY_ALLOCATION_ERROR;
        return NULL;
    }
    uprv_memset(swapper, 0, sizeof(UDataSwapper));

    /* set values and functions pointers according to in/out parameters */
    swapper->inIsBigEndian=inIsBigEndian;
    swapper->inCharset=inCharset;
    swapper->outIsBigEndian=outIsBigEndian;
    swapper->outCharset=outCharset;

    swapper->readUInt16= inIsBigEndian==U_IS_BIG_ENDIAN ? uprv_readDirectUInt16 : uprv_readSwapUInt16;
    swapper->readUInt32= inIsBigEndian==U_IS_BIG_ENDIAN ? uprv_readDirectUInt32 : uprv_readSwapUInt32;

    swapper->writeUInt16= outIsBigEndian==U_IS_BIG_ENDIAN ? uprv_writeDirectUInt16 : uprv_writeSwapUInt16;
    swapper->writeUInt32= outIsBigEndian==U_IS_BIG_ENDIAN ? uprv_writeDirectUInt32 : uprv_writeSwapUInt32;

    swapper->compareInvChars= outCharset==U_ASCII_FAMILY ? uprv_compareInvAscii : uprv_compareInvEbcdic;

    swapper->swapArray16= inIsBigEndian==outIsBigEndian ? uprv_copyArray16 : uprv_swapArray16;
    swapper->swapArray32= inIsBigEndian==outIsBigEndian ? uprv_copyArray32 : uprv_swapArray32;

    if(inCharset==U_ASCII_FAMILY) {
        swapper->swapInvChars= outCharset==U_ASCII_FAMILY ? uprv_copyAscii : uprv_ebcdicFromAscii;
    } else /* U_EBCDIC_FAMILY */ {
        swapper->swapInvChars= outCharset==U_EBCDIC_FAMILY ? uprv_copyEbcdic : uprv_asciiFromEbcdic;
    }

    return swapper;
}

U_CAPI UDataSwapper * U_EXPORT2
udata_openSwapperForInputData(const void *data, int32_t length,
                              UBool outIsBigEndian, uint8_t outCharset,
                              UErrorCode *pErrorCode) {
    const DataHeader *pHeader;
    uint16_t headerSize, infoSize;
    UBool inIsBigEndian;
    int8_t inCharset;

    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return NULL;
    }
    if( data==NULL ||
        (length>=0 && length<sizeof(DataHeader)) ||
        outCharset>U_EBCDIC_FAMILY
    ) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return NULL;
    }

    pHeader=(const DataHeader *)data;
    if( (length>=0 && length<sizeof(DataHeader)) ||
        pHeader->dataHeader.magic1!=0xda ||
        pHeader->dataHeader.magic2!=0x27 ||
        pHeader->info.sizeofUChar!=2
    ) {
        *pErrorCode=U_UNSUPPORTED_ERROR;
        return 0;
    }

    inIsBigEndian=(UBool)pHeader->info.isBigEndian;
    inCharset=pHeader->info.charsetFamily;

    if(inIsBigEndian==U_IS_BIG_ENDIAN) {
        headerSize=pHeader->dataHeader.headerSize;
        infoSize=pHeader->info.size;
    } else {
        headerSize=uprv_readSwapUInt16(pHeader->dataHeader.headerSize);
        infoSize=uprv_readSwapUInt16(pHeader->info.size);
    }

    if( headerSize<sizeof(DataHeader) ||
        infoSize<sizeof(UDataInfo) ||
        headerSize<(sizeof(pHeader->dataHeader)+infoSize) ||
        (length>=0 && length<headerSize)
    ) {
        *pErrorCode=U_UNSUPPORTED_ERROR;
        return 0;
    }

    return udata_openSwapper(inIsBigEndian, inCharset, outIsBigEndian, outCharset, pErrorCode);
}

U_CAPI void U_EXPORT2
udata_closeSwapper(UDataSwapper *ds) {
    uprv_free(ds);
}
Commit	Line	Data
374ca955 A	1	/*
	2	*******************************************************************************
	3	*
	4	* Copyright (C) 2003, International Business Machines
	5	* Corporation and others. All Rights Reserved.
	6	*
	7	*******************************************************************************
	8	* file name: udataswp.c
	9	* encoding: US-ASCII
	10	* tab size: 8 (not used)
	11	* indentation:4
	12	*
	13	* created on: 2003jun05
	14	* created by: Markus W. Scherer
	15	*
	16	* Definitions for ICU data transformations for different platforms,
	17	* changing between big- and little-endian data and/or between
	18	* charset families (ASCII<->EBCDIC).
	19	*/
	20
	21	#include <stdarg.h>
	22	#include "unicode/utypes.h"
	23	#include "unicode/udata.h" /* UDataInfo */
	24	#include "ucmndata.h" /* DataHeader */
	25	#include "cmemory.h"
	26	#include "udataswp.h"
	27
	28	/* swapping primitives ------------------------------------------------------ */
	29
	30	static int32_t U_CALLCONV
	31	uprv_swapArray16(const UDataSwapper *ds,
	32	const void inData, int32_t length, void outData,
	33	UErrorCode *pErrorCode) {
	34	const uint16_t *p;
	35	uint16_t *q;
	36	int32_t count;
	37	uint16_t x;
	38
	39	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
	40	return 0;
	41	}
	42	if(ds==NULL \|\| inData==NULL \|\| length<0 \|\| (length&1)!=0 \|\| outData==NULL) {
	43	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
	44	return 0;
	45	}
	46
	47	/* setup and swapping */
	48	p=(const uint16_t *)inData;
	49	q=(uint16_t *)outData;
	50	count=length/2;
	51	while(count>0) {
	52	x=*p++;
	53	*q++=(uint16_t)((x<<8)\|(x>>8));
	54	--count;
	55	}
	56
	57	return length;
	58	}
	59
	60	static int32_t U_CALLCONV
	61	uprv_copyArray16(const UDataSwapper *ds,
	62	const void inData, int32_t length, void outData,
	63	UErrorCode *pErrorCode) {
	64	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
65	return 0;
66	}
67	if(ds==NULL \|\| inData==NULL \|\| length<0 \|\| (length&1)!=0 \|\| outData==NULL) {
68	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
69	return 0;
70	}
71
72	if(length>0 && inData!=outData) {
73	uprv_memcpy(outData, inData, length);
74	}
75	return length;
76	}
77
78	static int32_t U_CALLCONV
79	uprv_swapArray32(const UDataSwapper *ds,
80	const void inData, int32_t length, void outData,
81	UErrorCode *pErrorCode) {
82	const uint32_t *p;
83	uint32_t *q;
84	int32_t count;
85	uint32_t x;
86
87	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
88	return 0;
89	}
90	if(ds==NULL \|\| inData==NULL \|\| length<0 \|\| (length&3)!=0 \|\| outData==NULL) {
91	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
92	return 0;
93	}
94
95	/* setup and swapping */
96	p=(const uint32_t *)inData;
97	q=(uint32_t *)outData;
98	count=length/4;
99	while(count>0) {
100	x=*p++;
101	*q++=(uint32_t)((x<<24)\|((x<<8)&0xff0000)\|((x>>8)&0xff00)\|(x>>24));
102	--count;
103	}
104
105	return length;
106	}
107
108	static int32_t U_CALLCONV
109	uprv_copyArray32(const UDataSwapper *ds,
110	const void inData, int32_t length, void outData,
111	UErrorCode *pErrorCode) {
112	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
113	return 0;
114	}
115	if(ds==NULL \|\| inData==NULL \|\| length<0 \|\| (length&3)!=0 \|\| outData==NULL) {
116	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
117	return 0;
118	}
119
120	if(length>0 && inData!=outData) {
121	uprv_memcpy(outData, inData, length);
122	}
123	return length;
124	}
125
126	static uint16_t U_CALLCONV
127	uprv_readSwapUInt16(uint16_t x) {
128	return (uint16_t)((x<<8)\|(x>>8));
129	}
130
131	static uint16_t U_CALLCONV
132	uprv_readDirectUInt16(uint16_t x) {
133	return x;
134	}
135
136	static uint32_t U_CALLCONV
137	uprv_readSwapUInt32(uint32_t x) {
138	return (uint32_t)((x<<24)\|((x<<8)&0xff0000)\|((x>>8)&0xff00)\|(x>>24));
139	}
140
141	static uint32_t U_CALLCONV
142	uprv_readDirectUInt32(uint32_t x) {
143	return x;
144	}
145
146	static void U_CALLCONV
147	uprv_writeSwapUInt16(uint16_t *p, uint16_t x) {
148	*p=(uint16_t)((x<<8)\|(x>>8));
149	}
150
151	static void U_CALLCONV
152	uprv_writeDirectUInt16(uint16_t *p, uint16_t x) {
153	*p=x;
154	}
155
156	static void U_CALLCONV
157	uprv_writeSwapUInt32(uint32_t *p, uint32_t x) {
158	*p=(uint32_t)((x<<24)\|((x<<8)&0xff0000)\|((x>>8)&0xff00)\|(x>>24));
159	}
160
161	static void U_CALLCONV
162	uprv_writeDirectUInt32(uint32_t *p, uint32_t x) {
163	*p=x;
164	}
165
166	U_CAPI int16_t U_EXPORT2
167	udata_readInt16(const UDataSwapper *ds, int16_t x) {
168	return (int16_t)ds->readUInt16((uint16_t)x);
169	}
170
171	U_CAPI int32_t U_EXPORT2
172	udata_readInt32(const UDataSwapper *ds, int32_t x) {
173	return (int32_t)ds->readUInt32((uint32_t)x);
174	}
175
176	/**
177	* Swap a block of invariant, NUL-terminated strings, but not padding
178	* bytes after the last string.
179	* @internal
180	*/
181	U_CAPI int32_t U_EXPORT2
182	udata_swapInvStringBlock(const UDataSwapper *ds,
183	const void inData, int32_t length, void outData,
184	UErrorCode *pErrorCode) {
185	const char *inChars;
186	int32_t stringsLength;
187
188	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
189	return 0;
190	}
191	if(ds==NULL \|\| inData==NULL \|\| length<0 \|\| (length>0 && outData==NULL)) {
192	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
193	return 0;
194	}
195
196	/* reduce the strings length to not include bytes after the last NUL */
197	inChars=(const char *)inData;
198	stringsLength=length;
199	while(stringsLength>0 && inChars[stringsLength-1]!=0) {
200	--stringsLength;
201	}
202
203	/* swap up to the last NUL */
204	ds->swapInvChars(ds, inData, stringsLength, outData, pErrorCode);
205
206	/* copy the bytes after the last NUL */
207	if(inData!=outData && length>stringsLength) {
208	uprv_memcpy((char *)outData+stringsLength, inChars+stringsLength, length-stringsLength);
209	}
210
211	/* return the length including padding bytes */
212	if(U_SUCCESS(*pErrorCode)) {
213	return length;
214	} else {
215	return 0;
216	}
217	}
218
219	U_CAPI void U_EXPORT2
220	udata_printError(const UDataSwapper *ds,
221	const char *fmt,
222	...) {
223	va_list args;
224
225	if(ds->printError!=NULL) {
226	va_start(args, fmt);
227	ds->printError(ds->printErrorContext, fmt, args);
228	va_end(args);
229	}
230	}
231
232	/* swap a data header ------------------------------------------------------- */
233
234	U_CAPI int32_t U_EXPORT2
235	udata_swapDataHeader(const UDataSwapper *ds,
236	const void inData, int32_t length, void outData,
237	UErrorCode *pErrorCode) {
238	const DataHeader *pHeader;
239	uint16_t headerSize, infoSize;
240
241	/* argument checking */
242	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
243	return 0;
244	}
245	if(ds==NULL \|\| inData==NULL \|\| length<-1 \|\| (length>0 && outData==NULL)) {
246	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
247	return 0;
248	}
249
250	/* check minimum length and magic bytes */
251	pHeader=(const DataHeader *)inData;
252	if( (length>=0 && length<sizeof(DataHeader)) \|\|
253	pHeader->dataHeader.magic1!=0xda \|\|
254	pHeader->dataHeader.magic2!=0x27 \|\|
255	pHeader->info.sizeofUChar!=2
256	) {
257	udata_printError(ds, "udata_swapDataHeader(): initial bytes do not look like ICU data\n");
258	*pErrorCode=U_UNSUPPORTED_ERROR;
259	return 0;
260	}
261
262	headerSize=ds->readUInt16(pHeader->dataHeader.headerSize);
263	infoSize=ds->readUInt16(pHeader->info.size);
264
265	if( headerSize<sizeof(DataHeader) \|\|
266	infoSize<sizeof(UDataInfo) \|\|
267	headerSize<(sizeof(pHeader->dataHeader)+infoSize) \|\|
268	(length>=0 && length<headerSize)
269	) {
270	udata_printError(ds, "udata_swapDataHeader(): header size mismatch - headerSize %d infoSize %d length %d\n",
271	headerSize, infoSize, length);
272	*pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
273	return 0;
274	}
275
276	if(length>0) {
277	DataHeader *outHeader;
278	const char *s;
279	int32_t maxLength;
280
281	/* Most of the fields are just bytes and need no swapping. */
282	if(inData!=outData) {
283	uprv_memcpy(outData, inData, headerSize);
284	}
285	outHeader=(DataHeader *)outData;
286
287	outHeader->info.isBigEndian = ds->outIsBigEndian;
288	outHeader->info.charsetFamily = ds->outCharset;
289
290	/* swap headerSize */
291	ds->swapArray16(ds, &pHeader->dataHeader.headerSize, 2, &outHeader->dataHeader.headerSize, pErrorCode);
292
293	/* swap UDataInfo size and reservedWord */
294	ds->swapArray16(ds, &pHeader->info.size, 4, &outHeader->info.size, pErrorCode);
295
296	/* swap copyright statement after the UDataInfo */
297	infoSize+=sizeof(pHeader->dataHeader);
298	s=(const char *)inData+infoSize;
299	maxLength=headerSize-infoSize;
300	/* get the length of the string */
301	for(length=0; length<maxLength && s[length]!=0; ++length) {}
302	/* swap the string contents */
303	ds->swapInvChars(ds, s, length, (char *)outData+infoSize, pErrorCode);
304	}
305
306	return headerSize;
307	}
308
309	/* API functions ------------------------------------------------------------ */
310
311	U_CAPI UDataSwapper * U_EXPORT2
312	udata_openSwapper(UBool inIsBigEndian, uint8_t inCharset,
313	UBool outIsBigEndian, uint8_t outCharset,
314	UErrorCode *pErrorCode) {
315	UDataSwapper *swapper;
316
317	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
318	return NULL;
319	}
320	if(inCharset>U_EBCDIC_FAMILY \|\| outCharset>U_EBCDIC_FAMILY) {
321	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
322	return NULL;
323	}
324
325	/* allocate the swapper */
326	swapper=uprv_malloc(sizeof(UDataSwapper));
327	if(swapper==NULL) {
328	*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
329	return NULL;
330	}
331	uprv_memset(swapper, 0, sizeof(UDataSwapper));
332
333	/* set values and functions pointers according to in/out parameters */
334	swapper->inIsBigEndian=inIsBigEndian;
335	swapper->inCharset=inCharset;
336	swapper->outIsBigEndian=outIsBigEndian;
337	swapper->outCharset=outCharset;
338
339	swapper->readUInt16= inIsBigEndian==U_IS_BIG_ENDIAN ? uprv_readDirectUInt16 : uprv_readSwapUInt16;
340	swapper->readUInt32= inIsBigEndian==U_IS_BIG_ENDIAN ? uprv_readDirectUInt32 : uprv_readSwapUInt32;
341
342	swapper->writeUInt16= outIsBigEndian==U_IS_BIG_ENDIAN ? uprv_writeDirectUInt16 : uprv_writeSwapUInt16;
343	swapper->writeUInt32= outIsBigEndian==U_IS_BIG_ENDIAN ? uprv_writeDirectUInt32 : uprv_writeSwapUInt32;
344
345	swapper->compareInvChars= outCharset==U_ASCII_FAMILY ? uprv_compareInvAscii : uprv_compareInvEbcdic;
346
347	swapper->swapArray16= inIsBigEndian==outIsBigEndian ? uprv_copyArray16 : uprv_swapArray16;
348	swapper->swapArray32= inIsBigEndian==outIsBigEndian ? uprv_copyArray32 : uprv_swapArray32;
349
350	if(inCharset==U_ASCII_FAMILY) {
351	swapper->swapInvChars= outCharset==U_ASCII_FAMILY ? uprv_copyAscii : uprv_ebcdicFromAscii;
352	} else /* U_EBCDIC_FAMILY */ {
353	swapper->swapInvChars= outCharset==U_EBCDIC_FAMILY ? uprv_copyEbcdic : uprv_asciiFromEbcdic;
354	}
355
356	return swapper;
357	}
358
359	U_CAPI UDataSwapper * U_EXPORT2
360	udata_openSwapperForInputData(const void *data, int32_t length,
361	UBool outIsBigEndian, uint8_t outCharset,
362	UErrorCode *pErrorCode) {
363	const DataHeader *pHeader;
364	uint16_t headerSize, infoSize;
365	UBool inIsBigEndian;
366	int8_t inCharset;
367
368	if(pErrorCode==NULL \|\| U_FAILURE(*pErrorCode)) {
369	return NULL;
370	}
371	if( data==NULL \|\|
372	(length>=0 && length<sizeof(DataHeader)) \|\|
373	outCharset>U_EBCDIC_FAMILY
374	) {
375	*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
376	return NULL;
377	}
378
379	pHeader=(const DataHeader *)data;
380	if( (length>=0 && length<sizeof(DataHeader)) \|\|
381	pHeader->dataHeader.magic1!=0xda \|\|
382	pHeader->dataHeader.magic2!=0x27 \|\|
383	pHeader->info.sizeofUChar!=2
384	) {
385	*pErrorCode=U_UNSUPPORTED_ERROR;
386	return 0;
387	}
388
389	inIsBigEndian=(UBool)pHeader->info.isBigEndian;
390	inCharset=pHeader->info.charsetFamily;
391
392	if(inIsBigEndian==U_IS_BIG_ENDIAN) {
393	headerSize=pHeader->dataHeader.headerSize;
394	infoSize=pHeader->info.size;
395	} else {
396	headerSize=uprv_readSwapUInt16(pHeader->dataHeader.headerSize);
397	infoSize=uprv_readSwapUInt16(pHeader->info.size);
398	}
399
400	if( headerSize<sizeof(DataHeader) \|\|
401	infoSize<sizeof(UDataInfo) \|\|
402	headerSize<(sizeof(pHeader->dataHeader)+infoSize) \|\|
403	(length>=0 && length<headerSize)
404	) {
405	*pErrorCode=U_UNSUPPORTED_ERROR;
406	return 0;
407	}
408
409	return udata_openSwapper(inIsBigEndian, inCharset, outIsBigEndian, outCharset, pErrorCode);
410	}
411
412	U_CAPI void U_EXPORT2
413	udata_closeSwapper(UDataSwapper *ds) {
414	uprv_free(ds);
415	}