Adding a new buf module for buffers
This also add converter functions between xmlBuf and xmlBuffer
* buf.c buf.h: the old xmlBuffer routines but modified for size_t
and using xmlBuf instead of xmlBuffer
* Makefile.am: add the 2 new files
* include/libxml/xmlerror.h: add an entry for the new module
* include/libxml/tree.h: expose the xmlBufPtr type but not the
structure which stay private
diff --git a/buf.c b/buf.c
new file mode 100644
index 0000000..520a024
--- /dev/null
+++ b/buf.c
@@ -0,0 +1,1138 @@
+/*
+ * buf.c: memory buffers for libxml2
+ *
+ * new buffer structures and entry points to simplify the maintainance
+ * of libxml2 and ensure we keep good control over memory allocations
+ * and stay 64 bits clean.
+ * The new entry point use the xmlBufPtr opaque structure and
+ * xmlBuf...() counterparts to the old xmlBuf...() functions
+ *
+ * See Copyright for the status of this software.
+ *
+ * daniel@veillard.com
+ */
+
+#define IN_LIBXML
+#include "libxml.h"
+
+#include <string.h> /* for memset() only ! */
+#include <limits.h>
+#ifdef HAVE_CTYPE_H
+#include <ctype.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
+#include <libxml/tree.h>
+#include <libxml/globals.h>
+#include <libxml/tree.h>
+#include "buf.h"
+
+/**
+ * xmlBuf:
+ *
+ * A buffer structure
+ */
+
+struct _xmlBuf {
+ xmlChar *content; /* The buffer content UTF8 */
+ size_t use; /* The buffer size used */
+ size_t size; /* The buffer size */
+ xmlBufferAllocationScheme alloc; /* The realloc method */
+ xmlChar *contentIO; /* in IO mode we may have a different base */
+ xmlBufferPtr buffer; /* wrapper for an old buffer */
+ int error; /* an error code if a failure occured */
+};
+
+/**
+ * xmlBufMemoryError:
+ * @extra: extra informations
+ *
+ * Handle an out of memory condition
+ * To be improved...
+ */
+static void
+xmlBufMemoryError(xmlBufPtr buf, const char *extra)
+{
+ __xmlSimpleError(XML_FROM_BUFFER, XML_ERR_NO_MEMORY, NULL, NULL, extra);
+ if ((buf) && (buf->error == 0))
+ buf->error = XML_ERR_NO_MEMORY;
+}
+
+/**
+ * xmlBufOverflowError:
+ * @extra: extra informations
+ *
+ * Handle a buffer overflow error
+ * To be improved...
+ */
+static void
+xmlBufOverflowError(xmlBufPtr buf, const char *extra)
+{
+ __xmlSimpleError(XML_FROM_BUFFER, XML_BUF_OVERFLOW, NULL, NULL, extra);
+ if ((buf) && (buf->error == 0))
+ buf->error = XML_BUF_OVERFLOW;
+}
+
+
+/**
+ * xmlBufCreate:
+ *
+ * routine to create an XML buffer.
+ * returns the new structure.
+ */
+xmlBufPtr
+xmlBufCreate(void) {
+ xmlBufPtr ret;
+
+ ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf));
+ if (ret == NULL) {
+ xmlBufMemoryError(NULL, "creating buffer");
+ return(NULL);
+ }
+ ret->use = 0;
+ ret->error = 0;
+ ret->buffer = NULL;
+ ret->size = xmlDefaultBufferSize;
+ ret->alloc = xmlBufferAllocScheme;
+ ret->content = (xmlChar *) xmlMallocAtomic(ret->size * sizeof(xmlChar));
+ if (ret->content == NULL) {
+ xmlBufMemoryError(ret, "creating buffer");
+ xmlFree(ret);
+ return(NULL);
+ }
+ ret->content[0] = 0;
+ ret->contentIO = NULL;
+ return(ret);
+}
+
+/**
+ * xmlBufCreateSize:
+ * @size: initial size of buffer
+ *
+ * routine to create an XML buffer.
+ * returns the new structure.
+ */
+xmlBufPtr
+xmlBufCreateSize(size_t size) {
+ xmlBufPtr ret;
+
+ ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf));
+ if (ret == NULL) {
+ xmlBufMemoryError(NULL, "creating buffer");
+ return(NULL);
+ }
+ ret->use = 0;
+ ret->error = 0;
+ ret->buffer = NULL;
+ ret->alloc = xmlBufferAllocScheme;
+ ret->size = (size ? size+2 : 0); /* +1 for ending null */
+ if (ret->size){
+ ret->content = (xmlChar *) xmlMallocAtomic(ret->size * sizeof(xmlChar));
+ if (ret->content == NULL) {
+ xmlBufMemoryError(ret, "creating buffer");
+ xmlFree(ret);
+ return(NULL);
+ }
+ ret->content[0] = 0;
+ } else
+ ret->content = NULL;
+ ret->contentIO = NULL;
+ return(ret);
+}
+
+/**
+ * xmlBufDetach:
+ * @buf: the buffer
+ *
+ * Remove the string contained in a buffer and gie it back to the
+ * caller. The buffer is reset to an empty content.
+ * This doesn't work with immutable buffers as they can't be reset.
+ *
+ * Returns the previous string contained by the buffer.
+ */
+xmlChar *
+xmlBufDetach(xmlBufPtr buf) {
+ xmlChar *ret;
+
+ if (buf == NULL)
+ return(NULL);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE)
+ return(NULL);
+ if (buf->buffer != NULL)
+ return(NULL);
+ if (buf->error)
+ return(NULL);
+
+ ret = buf->content;
+ buf->content = NULL;
+ buf->size = 0;
+ buf->use = 0;
+
+ return ret;
+}
+
+
+/**
+ * xmlBufCreateStatic:
+ * @mem: the memory area
+ * @size: the size in byte
+ *
+ * routine to create an XML buffer from an immutable memory area.
+ * The area won't be modified nor copied, and is expected to be
+ * present until the end of the buffer lifetime.
+ *
+ * returns the new structure.
+ */
+xmlBufPtr
+xmlBufCreateStatic(void *mem, size_t size) {
+ xmlBufPtr ret;
+
+ if ((mem == NULL) || (size == 0))
+ return(NULL);
+
+ ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf));
+ if (ret == NULL) {
+ xmlBufMemoryError(NULL, "creating buffer");
+ return(NULL);
+ }
+ ret->use = size;
+ ret->size = size;
+ ret->alloc = XML_BUFFER_ALLOC_IMMUTABLE;
+ ret->content = (xmlChar *) mem;
+ ret->error = 0;
+ ret->buffer = NULL;
+ return(ret);
+}
+
+/**
+ *
+ *
+ */
+int
+xmlBufGetAllocationScheme(xmlBufPtr buf) {
+ if (buf == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufGetAllocationScheme: buf == NULL\n");
+#endif
+ return(-1);
+ }
+ return(buf->alloc);
+}
+
+/**
+ * xmlBufSetAllocationScheme:
+ * @buf: the buffer to tune
+ * @scheme: allocation scheme to use
+ *
+ * Sets the allocation scheme for this buffer
+ *
+ * returns 0 in case of success and -1 in case of failure
+ */
+int
+xmlBufSetAllocationScheme(xmlBufPtr buf,
+ xmlBufferAllocationScheme scheme) {
+ if (buf == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufSetAllocationScheme: buf == NULL\n");
+#endif
+ return(-1);
+ }
+ if ((buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) ||
+ (buf->alloc == XML_BUFFER_ALLOC_IO))
+ return(-1);
+ if ((scheme == XML_BUFFER_ALLOC_DOUBLEIT) ||
+ (scheme == XML_BUFFER_ALLOC_EXACT) ||
+ (scheme == XML_BUFFER_ALLOC_HYBRID) ||
+ (scheme == XML_BUFFER_ALLOC_IMMUTABLE)) {
+ buf->alloc = scheme;
+ if (buf->buffer)
+ buf->buffer->alloc = scheme;
+ return(0);
+ }
+ /*
+ * Switching a buffer ALLOC_IO has the side effect of initializing
+ * the contentIO field with the current content
+ */
+ if (scheme == XML_BUFFER_ALLOC_IO) {
+ buf->alloc = XML_BUFFER_ALLOC_IO;
+ buf->contentIO = buf->content;
+ }
+ return(-1);
+}
+
+/**
+ * xmlBufFree:
+ * @buf: the buffer to free
+ *
+ * Frees an XML buffer. It frees both the content and the structure which
+ * encapsulate it.
+ */
+void
+xmlBufFree(xmlBufPtr buf) {
+ if (buf == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufFree: buf == NULL\n");
+#endif
+ return;
+ }
+
+ if ((buf->alloc == XML_BUFFER_ALLOC_IO) &&
+ (buf->contentIO != NULL)) {
+ xmlFree(buf->contentIO);
+ } else if ((buf->content != NULL) &&
+ (buf->alloc != XML_BUFFER_ALLOC_IMMUTABLE)) {
+ xmlFree(buf->content);
+ }
+ xmlFree(buf);
+}
+
+/**
+ * xmlBufEmpty:
+ * @buf: the buffer
+ *
+ * empty a buffer.
+ */
+void
+xmlBufEmpty(xmlBufPtr buf) {
+ if (buf == NULL) return;
+ if (buf->content == NULL) return;
+ buf->use = 0;
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) {
+ buf->content = BAD_CAST "";
+ } else if ((buf->alloc == XML_BUFFER_ALLOC_IO) &&
+ (buf->contentIO != NULL)) {
+ size_t start_buf = buf->content - buf->contentIO;
+
+ buf->size += start_buf;
+ buf->content = buf->contentIO;
+ buf->content[0] = 0;
+ } else {
+ buf->content[0] = 0;
+ }
+}
+
+/**
+ * xmlBufShrink:
+ * @buf: the buffer to dump
+ * @len: the number of xmlChar to remove
+ *
+ * Remove the beginning of an XML buffer.
+ * NOTE that this routine behaviour differs from xmlBufferShrink()
+ * as it will return 0 on error instead of -1 due to size_t being
+ * used as the return type.
+ *
+ * Returns the number of byte removed or 0 in case of failure
+ */
+size_t
+xmlBufShrink(xmlBufPtr buf, size_t len) {
+ if (buf == NULL) return(0);
+ if (len == 0) return(0);
+ if (len > buf->use) return(0);
+
+ buf->use -= len;
+ if ((buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) ||
+ ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL))) {
+ /*
+ * we just move the content pointer, but also make sure
+ * the perceived buffer size has shrinked accordingly
+ */
+ buf->content += len;
+ buf->size -= len;
+
+ /*
+ * sometimes though it maybe be better to really shrink
+ * on IO buffers
+ */
+ if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) {
+ size_t start_buf = buf->content - buf->contentIO;
+ if (start_buf >= buf->size) {
+ memmove(buf->contentIO, &buf->content[0], buf->use);
+ buf->content = buf->contentIO;
+ buf->content[buf->use] = 0;
+ buf->size += start_buf;
+ }
+ }
+ } else {
+ memmove(buf->content, &buf->content[len], buf->use);
+ buf->content[buf->use] = 0;
+ }
+ return(len);
+}
+
+/**
+ * xmlBufGrowInternal:
+ * @buf: the buffer
+ * @len: the minimum free size to allocate
+ *
+ * Grow the available space of an XML buffer, @len is the target value
+ * Error checking should be done on buf->error since using the return
+ * value doesn't work that well
+ *
+ * Returns 0 in case of error or the length made available otherwise
+ */
+static size_t
+xmlBufGrowInternal(xmlBufPtr buf, size_t len) {
+ size_t size;
+ xmlChar *newbuf;
+
+ if (buf == NULL) return(0);
+
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return(0);
+ if (buf->use + len < buf->size)
+ return(buf->size - buf->use);
+
+ /*
+ * Windows has a BIG problem on realloc timing, so we try to double
+ * the buffer size (if that's enough) (bug 146697)
+ * Apparently BSD too, and it's probably best for linux too
+ * On an embedded system this may be something to change
+ */
+#if 1
+ if (buf->size > (size_t) len)
+ size = buf->size * 2;
+ else
+ size = buf->use + len + 100;
+#else
+ size = buf->use + len + 100;
+#endif
+
+ if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) {
+ size_t start_buf = buf->content - buf->contentIO;
+
+ newbuf = (xmlChar *) xmlRealloc(buf->contentIO, start_buf + size);
+ if (newbuf == NULL) {
+ xmlBufMemoryError(buf, "growing buffer");
+ return(0);
+ }
+ buf->contentIO = newbuf;
+ buf->content = newbuf + start_buf;
+ } else {
+ newbuf = (xmlChar *) xmlRealloc(buf->content, size);
+ if (newbuf == NULL) {
+ xmlBufMemoryError(buf, "growing buffer");
+ return(0);
+ }
+ buf->content = newbuf;
+ }
+ buf->size = size;
+ return(buf->size - buf->use);
+}
+
+/**
+ * xmlBufGrow:
+ * @buf: the buffer
+ * @len: the minimum free size to allocate
+ *
+ * Grow the available space of an XML buffer, @len is the target value
+ * This is been kept compatible with xmlBufferGrow() as much as possible
+ *
+ * Returns -1 in case of error or the length made available otherwise
+ */
+int
+xmlBufGrow(xmlBufPtr buf, int len) {
+ size_t ret;
+
+ if ((buf == NULL) || (len < 0)) return(-1);
+ if (len == 0)
+ return(0);
+ ret = xmlBufGrowInternal(buf, len);
+ if (buf->error != 0)
+ return(-1);
+ return((int) ret);
+}
+
+/**
+ * xmlBufInflate:
+ * @buf: the buffer
+ * @len: the minimum extra free size to allocate
+ *
+ * Grow the available space of an XML buffer, adding at least @len bytes
+ *
+ * Returns 0 if successful or -1 in case of error
+ */
+int
+xmlBufInflate(xmlBufPtr buf, size_t len) {
+ if (buf == NULL) return(-1);
+ xmlBufGrowInternal(buf, len + buf->size);
+ if (buf->error)
+ return(-1);
+ return(0);
+}
+
+/**
+ * xmlBufDump:
+ * @file: the file output
+ * @buf: the buffer to dump
+ *
+ * Dumps an XML buffer to a FILE *.
+ * Returns the number of #xmlChar written
+ */
+size_t
+xmlBufDump(FILE *file, xmlBufPtr buf) {
+ size_t ret;
+
+ if (buf == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufDump: buf == NULL\n");
+#endif
+ return(0);
+ }
+ if (buf->content == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufDump: buf->content == NULL\n");
+#endif
+ return(0);
+ }
+ if (file == NULL)
+ file = stdout;
+ ret = fwrite(buf->content, sizeof(xmlChar), buf->use, file);
+ return(ret);
+}
+
+/**
+ * xmlBufContent:
+ * @buf: the buffer
+ *
+ * Function to extract the content of a buffer
+ *
+ * Returns the internal content
+ */
+
+xmlChar *
+xmlBufContent(const xmlBufPtr buf)
+{
+ if(!buf)
+ return NULL;
+
+ return(buf->content);
+}
+
+/**
+ * xmlBufEnd:
+ * @buf: the buffer
+ *
+ * Function to extract the end of the content of a buffer
+ *
+ * Returns the end of the internal content or NULL in case of error
+ */
+
+xmlChar *
+xmlBufEnd(const xmlBufPtr buf)
+{
+ if(!buf)
+ return NULL;
+
+ return(&buf->content[buf->use]);
+}
+
+/**
+ * xmlBufAddLen:
+ * @buf: the buffer
+ * @len: the size which were added at the end
+ *
+ * Sometime data may be added at the end of the buffer without
+ * using the xmlBuf APIs that is used to expand the used space
+ * and set the zero terminating at the end of the buffer
+ *
+ * Returns -1 in case of error and 0 otherwise
+ */
+int
+xmlBufAddLen(xmlBufPtr buf, size_t len) {
+ if ((buf == NULL) || (len > (buf->size - buf->use)))
+ return(-1);
+ buf->use += len;
+ if (buf->size > buf->use)
+ buf->content[buf->use] = 0;
+ else
+ return(-1);
+ return(0);
+}
+
+/**
+ * xmlBufErase:
+ * @buf: the buffer
+ * @len: the size to erase at the end
+ *
+ * Sometime data need to be erased at the end of the buffer
+ *
+ * Returns -1 in case of error and 0 otherwise
+ */
+int
+xmlBufErase(xmlBufPtr buf, size_t len) {
+ if ((buf == NULL) || (len > buf->use))
+ return(-1);
+ buf->use -= len;
+ buf->content[buf->use] = 0;
+ return(0);
+}
+
+/**
+ * xmlBufLength:
+ * @buf: the buffer
+ *
+ * Function to get the length of a buffer
+ *
+ * Returns the length of data in the internal content
+ */
+
+size_t
+xmlBufLength(const xmlBufPtr buf)
+{
+ if (!buf)
+ return 0;
+
+ return(buf->use);
+}
+
+/**
+ * xmlBufUse:
+ * @buf: the buffer
+ *
+ * Function to get the length of a buffer
+ *
+ * Returns the length of data in the internal content
+ */
+
+size_t
+xmlBufUse(const xmlBufPtr buf)
+{
+ if (!buf)
+ return 0;
+
+ return(buf->use);
+}
+
+/**
+ * xmlBufAvail:
+ * @buf: the buffer
+ *
+ * Function to find how much free space is allocated but not
+ * used in the buffer. It does not account for the terminating zero
+ * usually needed
+ *
+ * Returns the amount or 0 if none or an error occured
+ */
+
+size_t
+xmlBufAvail(const xmlBufPtr buf)
+{
+ if (!buf)
+ return 0;
+
+ return(buf->size - buf->use);
+}
+
+/**
+ * xmlBufIsEmpty:
+ * @buf: the buffer
+ *
+ * Tell if a buffer is empty
+ *
+ * Returns 0 if no, 1 if yes and -1 in case of error
+ */
+int
+xmlBufIsEmpty(const xmlBufPtr buf)
+{
+ if(!buf)
+ return(-1);
+
+ return(buf->use == 0);
+}
+
+/**
+ * xmlBufResize:
+ * @buf: the buffer to resize
+ * @size: the desired size
+ *
+ * Resize a buffer to accommodate minimum size of @size.
+ *
+ * Returns 0 in case of problems, 1 otherwise
+ */
+int
+xmlBufResize(xmlBufPtr buf, size_t size)
+{
+ unsigned int newSize;
+ xmlChar* rebuf = NULL;
+ size_t start_buf;
+
+ if (buf == NULL)
+ return(0);
+
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return(0);
+
+ /* Don't resize if we don't have to */
+ if (size < buf->size)
+ return 1;
+
+ /* figure out new size */
+ switch (buf->alloc){
+ case XML_BUFFER_ALLOC_IO:
+ case XML_BUFFER_ALLOC_DOUBLEIT:
+ /*take care of empty case*/
+ newSize = (buf->size ? buf->size*2 : size + 10);
+ while (size > newSize) {
+ if (newSize > UINT_MAX / 2) {
+ xmlBufMemoryError(buf, "growing buffer");
+ return 0;
+ }
+ newSize *= 2;
+ }
+ break;
+ case XML_BUFFER_ALLOC_EXACT:
+ newSize = size+10;
+ break;
+ case XML_BUFFER_ALLOC_HYBRID:
+ if (buf->use < BASE_BUFFER_SIZE)
+ newSize = size;
+ else {
+ newSize = buf->size * 2;
+ while (size > newSize) {
+ if (newSize > UINT_MAX / 2) {
+ xmlBufMemoryError(buf, "growing buffer");
+ return 0;
+ }
+ newSize *= 2;
+ }
+ }
+ break;
+
+ default:
+ newSize = size+10;
+ break;
+ }
+
+ if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) {
+ start_buf = buf->content - buf->contentIO;
+
+ if (start_buf > newSize) {
+ /* move data back to start */
+ memmove(buf->contentIO, buf->content, buf->use);
+ buf->content = buf->contentIO;
+ buf->content[buf->use] = 0;
+ buf->size += start_buf;
+ } else {
+ rebuf = (xmlChar *) xmlRealloc(buf->contentIO, start_buf + newSize);
+ if (rebuf == NULL) {
+ xmlBufMemoryError(buf, "growing buffer");
+ return 0;
+ }
+ buf->contentIO = rebuf;
+ buf->content = rebuf + start_buf;
+ }
+ } else {
+ if (buf->content == NULL) {
+ rebuf = (xmlChar *) xmlMallocAtomic(newSize);
+ } else if (buf->size - buf->use < 100) {
+ rebuf = (xmlChar *) xmlRealloc(buf->content, newSize);
+ } else {
+ /*
+ * if we are reallocating a buffer far from being full, it's
+ * better to make a new allocation and copy only the used range
+ * and free the old one.
+ */
+ rebuf = (xmlChar *) xmlMallocAtomic(newSize);
+ if (rebuf != NULL) {
+ memcpy(rebuf, buf->content, buf->use);
+ xmlFree(buf->content);
+ rebuf[buf->use] = 0;
+ }
+ }
+ if (rebuf == NULL) {
+ xmlBufMemoryError(buf, "growing buffer");
+ return 0;
+ }
+ buf->content = rebuf;
+ }
+ buf->size = newSize;
+
+ return 1;
+}
+
+/**
+ * xmlBufAdd:
+ * @buf: the buffer to dump
+ * @str: the #xmlChar string
+ * @len: the number of #xmlChar to add
+ *
+ * Add a string range to an XML buffer. if len == -1, the length of
+ * str is recomputed.
+ *
+ * Returns 0 successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufAdd(xmlBufPtr buf, const xmlChar *str, int len) {
+ unsigned int needSize;
+
+ if ((str == NULL) || (buf == NULL)) {
+ return -1;
+ }
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1;
+ if (len < -1) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufAdd: len < 0\n");
+#endif
+ return -1;
+ }
+ if (len == 0) return 0;
+
+ if (len < 0)
+ len = xmlStrlen(str);
+
+ if (len < 0) return -1;
+ if (len == 0) return 0;
+
+ needSize = buf->use + len + 2;
+ if (needSize > buf->size){
+ if (!xmlBufResize(buf, needSize)){
+ xmlBufMemoryError(buf, "growing buffer");
+ return XML_ERR_NO_MEMORY;
+ }
+ }
+
+ memmove(&buf->content[buf->use], str, len*sizeof(xmlChar));
+ buf->use += len;
+ buf->content[buf->use] = 0;
+ return 0;
+}
+
+/**
+ * xmlBufAddHead:
+ * @buf: the buffer
+ * @str: the #xmlChar string
+ * @len: the number of #xmlChar to add
+ *
+ * Add a string range to the beginning of an XML buffer.
+ * if len == -1, the length of @str is recomputed.
+ *
+ * Returns 0 successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufAddHead(xmlBufPtr buf, const xmlChar *str, int len) {
+ unsigned int needSize;
+
+ if (buf == NULL)
+ return(-1);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1;
+ if (str == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufAddHead: str == NULL\n");
+#endif
+ return -1;
+ }
+ if (len < -1) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufAddHead: len < 0\n");
+#endif
+ return -1;
+ }
+ if (len == 0) return 0;
+
+ if (len < 0)
+ len = xmlStrlen(str);
+
+ if (len <= 0) return -1;
+
+ if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) {
+ size_t start_buf = buf->content - buf->contentIO;
+
+ if (start_buf > (unsigned int) len) {
+ /*
+ * We can add it in the space previously shrinked
+ */
+ buf->content -= len;
+ memmove(&buf->content[0], str, len);
+ buf->use += len;
+ buf->size += len;
+ return(0);
+ }
+ }
+ needSize = buf->use + len + 2;
+ if (needSize > buf->size){
+ if (!xmlBufResize(buf, needSize)){
+ xmlBufMemoryError(buf, "growing buffer");
+ return XML_ERR_NO_MEMORY;
+ }
+ }
+
+ memmove(&buf->content[len], &buf->content[0], buf->use);
+ memmove(&buf->content[0], str, len);
+ buf->use += len;
+ buf->content[buf->use] = 0;
+ return 0;
+}
+
+/**
+ * xmlBufCat:
+ * @buf: the buffer to add to
+ * @str: the #xmlChar string
+ *
+ * Append a zero terminated string to an XML buffer.
+ *
+ * Returns 0 successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufCat(xmlBufPtr buf, const xmlChar *str) {
+ if (buf == NULL)
+ return(-1);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1;
+ if (str == NULL) return -1;
+ return xmlBufAdd(buf, str, -1);
+}
+
+/**
+ * xmlBufCCat:
+ * @buf: the buffer to dump
+ * @str: the C char string
+ *
+ * Append a zero terminated C string to an XML buffer.
+ *
+ * Returns 0 successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufCCat(xmlBufPtr buf, const char *str) {
+ const char *cur;
+
+ if (buf == NULL)
+ return(-1);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1;
+ if (str == NULL) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufCCat: str == NULL\n");
+#endif
+ return -1;
+ }
+ for (cur = str;*cur != 0;cur++) {
+ if (buf->use + 10 >= buf->size) {
+ if (!xmlBufResize(buf, buf->use+10)){
+ xmlBufMemoryError(buf, "growing buffer");
+ return XML_ERR_NO_MEMORY;
+ }
+ }
+ buf->content[buf->use++] = *cur;
+ }
+ buf->content[buf->use] = 0;
+ return 0;
+}
+
+/**
+ * xmlBufWriteCHAR:
+ * @buf: the XML buffer
+ * @string: the string to add
+ *
+ * routine which manages and grows an output buffer. This one adds
+ * xmlChars at the end of the buffer.
+ *
+ * Returns 0 if successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufWriteCHAR(xmlBufPtr buf, const xmlChar *string) {
+ if (buf == NULL)
+ return(-1);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE)
+ return(-1);
+ return(xmlBufCat(buf, string));
+}
+
+/**
+ * xmlBufWriteChar:
+ * @buf: the XML buffer output
+ * @string: the string to add
+ *
+ * routine which manage and grows an output buffer. This one add
+ * C chars at the end of the array.
+ *
+ * Returns 0 if successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufWriteChar(xmlBufPtr buf, const char *string) {
+ if (buf == NULL)
+ return(-1);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE)
+ return(-1);
+ return(xmlBufCCat(buf, string));
+}
+
+
+/**
+ * xmlBufWriteQuotedString:
+ * @buf: the XML buffer output
+ * @string: the string to add
+ *
+ * routine which manage and grows an output buffer. This one writes
+ * a quoted or double quoted #xmlChar string, checking first if it holds
+ * quote or double-quotes internally
+ *
+ * Returns 0 if successful, a positive error code number otherwise
+ * and -1 in case of internal or API error.
+ */
+int
+xmlBufWriteQuotedString(xmlBufPtr buf, const xmlChar *string) {
+ const xmlChar *cur, *base;
+ if (buf == NULL)
+ return(-1);
+ if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE)
+ return(-1);
+ if (xmlStrchr(string, '\"')) {
+ if (xmlStrchr(string, '\'')) {
+#ifdef DEBUG_BUFFER
+ xmlGenericError(xmlGenericErrorContext,
+ "xmlBufWriteQuotedString: string contains quote and double-quotes !\n");
+#endif
+ xmlBufCCat(buf, "\"");
+ base = cur = string;
+ while(*cur != 0){
+ if(*cur == '"'){
+ if (base != cur)
+ xmlBufAdd(buf, base, cur - base);
+ xmlBufAdd(buf, BAD_CAST """, 6);
+ cur++;
+ base = cur;
+ }
+ else {
+ cur++;
+ }
+ }
+ if (base != cur)
+ xmlBufAdd(buf, base, cur - base);
+ xmlBufCCat(buf, "\"");
+ }
+ else{
+ xmlBufCCat(buf, "\'");
+ xmlBufCat(buf, string);
+ xmlBufCCat(buf, "\'");
+ }
+ } else {
+ xmlBufCCat(buf, "\"");
+ xmlBufCat(buf, string);
+ xmlBufCCat(buf, "\"");
+ }
+ return(0);
+}
+
+/**
+ * xmlBufFromBuffer:
+ * @buffer: incoming old buffer to convert to a new one
+ *
+ * Helper routine to switch from the old buffer structures in use
+ * in various APIs. It creates a wrapper xmlBufPtr which will be
+ * used for internal processing until the xmlBufBackToBuffer() is
+ * issued.
+ *
+ * Returns a new xmlBufPtr unless the call failed and NULL is returned
+ */
+xmlBufPtr
+xmlBufFromBuffer(xmlBufferPtr buffer) {
+ xmlBufPtr ret;
+
+ if (buffer == NULL)
+ return(NULL);
+
+ ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf));
+ if (ret == NULL) {
+ xmlBufMemoryError(NULL, "creating buffer");
+ return(NULL);
+ }
+ ret->use = buffer->use;
+ ret->size = buffer->size;
+ ret->error = 0;
+ ret->buffer = buffer;
+ ret->alloc = buffer->alloc;
+ ret->content = buffer->content;
+ ret->contentIO = buffer->contentIO;
+
+ return(ret);
+}
+
+/**
+ * xmlBufBackToBuffer:
+ * @buf: new buffer wrapping the old one
+ *
+ * Function to be called once internal processing had been done to
+ * update back the buffer provided by the user. This can lead to
+ * a failure in case the size accumulated in the xmlBuf is larger
+ * than what an xmlBuffer can support on 64 bits (INT_MAX)
+ * The xmlBufPtr @buf wrapper is deallocated by this call in any case.
+ *
+ * Returns the old xmlBufferPtr unless the call failed and NULL is returned
+ */
+xmlBufferPtr
+xmlBufBackToBuffer(xmlBufPtr buf) {
+ xmlBufferPtr ret;
+
+ if (buf == NULL)
+ return(NULL);
+ if (buf->buffer == NULL) {
+ xmlBufFree(buf);
+ return(NULL);
+ }
+
+ ret = buf->buffer;
+ /*
+ * What to do in case of error in the buffer ???
+ */
+ if (buf->use > INT_MAX) {
+ /*
+ * Worse case, we really allocated and used more than the
+ * maximum allowed memory for an xmlBuffer on this architecture.
+ * Keep the buffer but provide a truncated size value.
+ */
+ xmlBufOverflowError(buf, "Used size too big for xmlBuffer");
+ ret->use = INT_MAX;
+ ret->size = INT_MAX;
+ } else if (buf->size > INT_MAX) {
+ /*
+ * milder case, we allocated more than the maximum allowed memory
+ * for an xmlBuffer on this architecture, but used less than the
+ * limit.
+ * Keep the buffer but provide a truncated size value.
+ */
+ xmlBufOverflowError(buf, "Allocated size too big for xmlBuffer");
+ ret->size = INT_MAX;
+ }
+ ret->use = (int) buf->use;
+ ret->size = (int) buf->size;
+ ret->alloc = buf->alloc;
+ ret->content = buf->content;
+ ret->contentIO = buf->contentIO;
+ xmlFree(buf);
+ return(ret);
+}
+
+/**
+ * xmlBufMergeBuffer:
+ * @buf: an xmlBufPtr
+ * @buffer: the buffer to consume into @buf
+ *
+ * The content of @buffer is appended to @buf and @buffer is freed
+ *
+ * Returns -1 in case of error, 0 otherwise, in any case @buffer is freed
+ */
+int
+xmlBufMergeBuffer(xmlBufPtr buf, xmlBufferPtr buffer) {
+ int ret;
+
+ if (buffer == NULL)
+ return(0);
+ if ((buf != NULL) && (buffer->content != NULL) && (buffer->use > 0)) {
+ ret = xmlBufAdd(buf, buffer->content, buffer->use);
+ }
+ xmlBufferFree(buffer);
+ return(ret);
+}