xmlwriter.c

libxml,在UNIX/LINUX下非常重要的一个库,为XML相关应用提供方便.目前上载的是最新版本,若要取得最新版本,请参考里面的readme.

        int c;
        int n;

        igroup[0] = igroup[1] = igroup[2] = 0;
        for (n = 0; n < 3 && i < len; n++, i++) {
            c = data[i];
            igroup[n] = (unsigned char) c;
        }

        if (n > 0) {
            ogroup[0] = dtable[igroup[0] >> 2];
            ogroup[1] = dtable[((igroup[0] & 3) << 4) | (igroup[1] >> 4)];
            ogroup[2] =
                dtable[((igroup[1] & 0xF) << 2) | (igroup[2] >> 6)];
            ogroup[3] = dtable[igroup[2] & 0x3F];

            if (n < 3) {
                ogroup[3] = '=';
                if (n < 2) {
                    ogroup[2] = '=';
                }
            }

            if (linelen >= B64LINELEN) {
                count = xmlOutputBufferWrite(out, 2, B64CRLF);
                if (count == -1)
                    return -1;
                sum += count;
                linelen = 0;
            }
            count = xmlOutputBufferWrite(out, 4, (const char *) ogroup);
            if (count == -1)
                return -1;
            sum += count;

            linelen += 4;
        }

        if (i >= len)
            break;
    }

    return sum;
}

/**
 * xmlTextWriterWriteBase64:
 * @writer: the xmlTextWriterPtr
 * @data:   binary data
 * @start:  the position within the data of the first byte to encode
 * @len:  the number of bytes to encode
 *
 * Write an base64 encoded xml text.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterWriteBase64(xmlTextWriterPtr writer, const char *data,
                         int start, int len)
{
    int count;
    int sum;
    xmlLinkPtr lk;
    xmlTextWriterStackEntry *p;

    if ((writer == NULL) || (data == NULL) || (start < 0) || (len < 0))
        return -1;

    sum = 0;
    lk = xmlListFront(writer->nodes);
    if (lk != 0) {
        p = (xmlTextWriterStackEntry *) xmlLinkGetData(lk);
        if (p != 0) {
            count = xmlTextWriterHandleStateDependencies(writer, p);
            if (count < 0)
                return -1;
            sum += count;
        }
    }

    if (writer->indent)
        writer->doindent = 0;

    count =
        xmlOutputBufferWriteBase64(writer->out, len,
                                   (unsigned char *) data + start);
    if (count < 0)
        return -1;
    sum += count;

    return sum;
}

/**
 * xmlOutputBufferWriteBinHex:
 * @out: the xmlOutputBufferPtr
 * @data:   binary data
 * @len:  the number of bytes to encode
 *
 * Write hqx encoded data to an xmlOutputBuffer.
 * ::todo
 *
 * Returns the bytes written (may be 0 because of buffering) 
 * or -1 in case of error
 */
static int
xmlOutputBufferWriteBinHex(xmlOutputBufferPtr out,
                           int len, const unsigned char *data)
{
    int count;
    int sum;
    static char hex[16] = 
    	{'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
    int i;

    if ((out == NULL) || (data == NULL) || (len < 0)) {
        return -1;
    }

    sum = 0;
    for (i = 0; i < len; i++) {
        count =
            xmlOutputBufferWrite(out, 1,
                                 (const char *) &hex[data[i] >> 4]);
        if (count == -1)
            return -1;
        sum += count;
        count =
            xmlOutputBufferWrite(out, 1,
                                 (const char *) &hex[data[i] & 0xF]);
        if (count == -1)
            return -1;
        sum += count;
    }

    return sum;
}

/**
 * xmlTextWriterWriteBinHex:
 * @writer: the xmlTextWriterPtr
 * @data:   binary data
 * @start:  the position within the data of the first byte to encode
 * @len:  the number of bytes to encode
 *
 * Write a BinHex encoded xml text.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterWriteBinHex(xmlTextWriterPtr writer, const char *data,
                         int start, int len)
{
    int count;
    int sum;
    xmlLinkPtr lk;
    xmlTextWriterStackEntry *p;

    if ((writer == NULL) || (data == NULL) || (start < 0) || (len < 0))
        return -1;

    sum = 0;
    lk = xmlListFront(writer->nodes);
    if (lk != 0) {
        p = (xmlTextWriterStackEntry *) xmlLinkGetData(lk);
        if (p != 0) {
            count = xmlTextWriterHandleStateDependencies(writer, p);
            if (count < 0)
                return -1;
            sum += count;
        }
    }

    if (writer->indent)
        writer->doindent = 0;

    count =
        xmlOutputBufferWriteBinHex(writer->out, len,
                                   (unsigned char *) data + start);
    if (count < 0)
        return -1;
    sum += count;

    return sum;
}

/**
 * xmlTextWriterStartAttribute:
 * @writer:  the xmlTextWriterPtr
 * @name:  element name
 *
 * Start an xml attribute.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterStartAttribute(xmlTextWriterPtr writer, const xmlChar * name)
{
    int count;
    int sum;
    xmlLinkPtr lk;
    xmlTextWriterStackEntry *p;

    if ((writer == NULL) || (name == NULL) || (*name == '\0'))
        return -1;

    sum = 0;
    lk = xmlListFront(writer->nodes);
    if (lk == 0)
        return -1;

    p = (xmlTextWriterStackEntry *) xmlLinkGetData(lk);
    if (p == 0)
        return -1;

    switch (p->state) {
        case XML_TEXTWRITER_ATTRIBUTE:
            count = xmlTextWriterEndAttribute(writer);
            if (count < 0)
                return -1;
            sum += count;
            /* fallthrough */
        case XML_TEXTWRITER_NAME:
            count = xmlOutputBufferWriteString(writer->out, " ");
            if (count < 0)
                return -1;
            sum += count;
            count =
                xmlOutputBufferWriteString(writer->out,
                                           (const char *) name);
            if (count < 0)
                return -1;
            sum += count;
            count = xmlOutputBufferWriteString(writer->out, "=");
            if (count < 0)
                return -1;
            sum += count;
            count = xmlOutputBufferWrite(writer->out, 1, &writer->qchar);
            if (count < 0)
                return -1;
            sum += count;
            p->state = XML_TEXTWRITER_ATTRIBUTE;
            break;
        default:
            return -1;
    }

    return sum;
}

/**
 * xmlTextWriterStartAttributeNS:
 * @writer:  the xmlTextWriterPtr
 * @prefix:  namespace prefix or NULL
 * @name:  element local name
 * @namespaceURI:  namespace URI or NULL
 *
 * Start an xml attribute with namespace support.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterStartAttributeNS(xmlTextWriterPtr writer,
                              const xmlChar * prefix, const xmlChar * name,
                              const xmlChar * namespaceURI)
{
    int count;
    int sum;
    xmlChar *buf;
    xmlTextWriterNsStackEntry *p;

    if ((writer == NULL) || (name == NULL) || (*name == '\0'))
        return -1;

    buf = 0;
    if (prefix != 0) {
        buf = xmlStrdup(prefix);
        buf = xmlStrcat(buf, BAD_CAST ":");
    }
    buf = xmlStrcat(buf, name);

    sum = 0;
    count = xmlTextWriterStartAttribute(writer, buf);
    xmlFree(buf);
    if (count < 0)
        return -1;
    sum += count;

    if (namespaceURI != 0) {
        buf = xmlStrdup(BAD_CAST "xmlns");
        if (prefix != 0) {
            buf = xmlStrcat(buf, BAD_CAST ":");
            buf = xmlStrcat(buf, prefix);
        }

        p = (xmlTextWriterNsStackEntry *)
            xmlMalloc(sizeof(xmlTextWriterNsStackEntry));
        if (p == 0) {
            xmlWriterErrMsg(writer, XML_ERR_NO_MEMORY,
                            "xmlTextWriterStartAttributeNS : out of memory!\n");
            return -1;
        }

        p->prefix = buf;
        p->uri = xmlStrdup(namespaceURI);
        if (p->uri == 0) {
            xmlWriterErrMsg(writer, XML_ERR_NO_MEMORY,
                            "xmlTextWriterStartAttributeNS : out of memory!\n");
            xmlFree(p);
            return -1;
        }
        p->elem = xmlListFront(writer->nodes);

        xmlListPushFront(writer->nsstack, p);
    }

    return sum;
}

/**
 * xmlTextWriterEndAttribute:
 * @writer:  the xmlTextWriterPtr
 *
 * End the current xml element.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterEndAttribute(xmlTextWriterPtr writer)
{
    int count;
    int sum;
    xmlLinkPtr lk;
    xmlTextWriterStackEntry *p;
    xmlTextWriterNsStackEntry *np;

    if (writer == NULL)
        return -1;

    lk = xmlListFront(writer->nodes);
    if (lk == 0) {
        xmlListDelete(writer->nsstack);
	writer->nsstack = NULL;
        return -1;
    }

    p = (xmlTextWriterStackEntry *) xmlLinkGetData(lk);
    if (p == 0) {
        xmlListDelete(writer->nsstack);
	writer->nsstack = NULL;
        return -1;
    }

    sum = 0;
    switch (p->state) {
        case XML_TEXTWRITER_ATTRIBUTE:
            p->state = XML_TEXTWRITER_NAME;

            count = xmlOutputBufferWrite(writer->out, 1, &writer->qchar);
            if (count < 0) {
                xmlListDelete(writer->nsstack);
		writer->nsstack = NULL;
                return -1;
            }
            sum += count;

            while (!xmlListEmpty(writer->nsstack)) {
	        xmlChar *namespaceURI = NULL;
		xmlChar *prefix = NULL;

                lk = xmlListFront(writer->nsstack);
                np = (xmlTextWriterNsStackEntry *) xmlLinkGetData(lk);

		if (np != 0) {
		    namespaceURI = xmlStrdup(np->uri);
		    prefix = xmlStrdup(np->prefix);
		}

		xmlListPopFront(writer->nsstack);

                if (np != 0) {
                    count =
                        xmlTextWriterWriteAttribute(writer, prefix,
                                                    namespaceURI);
		    xmlFree(namespaceURI);
		    xmlFree(prefix);

                    if (count < 0) {
                        xmlListDelete(writer->nsstack);
			writer->nsstack = NULL;
                        return -1;
                    }
                    sum += count;
                }
            }
            break;

        default:
            xmlListClear(writer->nsstack);
            return -1;
    }

    return sum;
}

/**
 * xmlTextWriterWriteFormatAttribute:
 * @writer:  the xmlTextWriterPtr
 * @name:  attribute name
 * @format:  format string (see printf)
 * @...:  extra parameters for the format
 *
 * Write a formatted xml attribute.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterWriteFormatAttribute(xmlTextWriterPtr writer,
                                  const xmlChar * name, const char *format,
                                  ...)
{
    int rc;
    va_list ap;

    va_start(ap, format);

    rc = xmlTextWriterWriteVFormatAttribute(writer, name, format, ap);

    va_end(ap);
    return rc;
}

/**
 * xmlTextWriterWriteVFormatAttribute:
 * @writer:  the xmlTextWriterPtr
 * @name:  attribute name
 * @format:  format string (see printf)
 * @argptr:  pointer to the first member of the variable argument list.
 *
 * Write a formatted xml attribute.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterWriteVFormatAttribute(xmlTextWriterPtr writer,
                                   const xmlChar * name,
                                   const char *format, va_list argptr)
{
    int rc;
    xmlChar *buf;

    if (writer == NULL)
        return -1;

    buf = xmlTextWriterVSprintf(format, argptr);
    if (buf == 0)
        return 0;

    rc = xmlTextWriterWriteAttribute(writer, name, buf);

    xmlFree(buf);
    return rc;
}

/**
 * xmlTextWriterWriteAttribute:
 * @writer:  the xmlTextWriterPtr
 * @name:  attribute name
 * @content:  attribute content
 *
 * Write an xml attribute.
 *
 * Returns the bytes written (may be 0 because of buffering) or -1 in case of error
 */
int
xmlTextWriterWriteAttribute(xmlTextWriterPtr writer, const xmlChar * name,
                            const xmlChar * content)
{
    int count;
    int sum;

    sum = 0;
    count = xmlTextWriterStartAttribute(writer, name);
    if (count < 0)
        return -1;
    sum += count;
    count = xmlTextWriterWriteString(writer, content);
    if (count < 0)
        return -1;
    sum += count;
    count = xmlTextWriterEndAttribute(writer);