* add new libxml sample

git-svn-id: trunk@11631 -

.gitattributes

@@ -3286,6 +3286,7 @@ packages/libxml/csrc/xpointer.h svneol=native#text/plain
 packages/libxml/examples/Makefile svneol=native#text/plain
 packages/libxml/examples/Makefile.fpc svneol=native#text/plain
 packages/libxml/examples/exutils.pas svneol=native#text/plain
+packages/libxml/examples/io1.pas svneol=native#text/plain
 packages/libxml/examples/reader1.pas svneol=native#text/plain
 packages/libxml/examples/reader2.pas svneol=native#text/plain
 packages/libxml/examples/test1.xml svneol=native#text/plain

packages/libxml/examples/io1.pas

@@ -0,0 +1,169 @@
+(**
+ * section: InputOutput
+ * synopsis: Example of custom Input/Output
+ * purpose: Demonstrate the use of xmlRegisterInputCallbacks
+ *          to build a custom I/O layer, this is used in an
+ *          XInclude method context to show how dynamic document can
+ *          be built in a clean way.
+ * usage: io1
+ * test: io1 > io1.tmp ; diff io1.tmp io1.res ; rm -f io1.tmp
+ * author: Daniel Veillard
+ * copy: see Copyright for the status of this software.
+ *)
+
+program io1;
+
+{$mode objfpc}
+
+uses
+  ctypes,
+  libxml2,
+  exutils;
+
+const
+  include: pchar =
+    '<?xml version=''1.0''?>'#10+
+    '<document xmlns:xi="http://www.w3.org/2003/XInclude">'#10+
+      '<p>List of people:</p>'#10+
+      '<xi:include href="sql:select_name_from_people"/>'#10+
+    '</document>'#10;
+
+
+(**
+ * sqlMatch:
+ * @URI: an URI to test
+ *
+ * Check for an sql: query
+ *
+ * Returns 1 if yes and 0 if another Input module should be used
+ *)
+function sqlMatch(URI: pchar): cint; cdecl;
+begin
+  if assigned(URI) {and (strncmp(URI, 'sql:', 4) = 0)} then
+    result := 1
+  else
+    result := 0;
+end;
+
+(**
+ * sqlOpen:
+ * @URI: an URI to test
+ *
+ * Return a pointer to the sql: query handler, in this example simply
+ * the current pointer...
+ *
+ * Returns an Input context or NULL in case or error
+ *)
+function sqlOpen(URI: pchar): pointer; cdecl;
+begin
+  if not assigned(URI) or (strncmp(URI, 'sql:', 4) <> 0) then
+    exit(nil);
+
+  
+end;
+{
+    if ((URI == NULL) || (strncmp(URI, "sql:", 4)))
+        return(NULL);
+    cur = result;
+    rlen = strlen(result);
+    return((void *) cur);
+}
+
+(**
+ * sqlClose:
+ * @context: the read context
+ *
+ * Close the sql: query handler
+ *
+ * Returns 0 or -1 in case of error
+ *)
+function sqlClose(context: pointer): cint; cdecl;
+begin
+end; {
+    if (context == NULL) return(-1);
+    cur = NULL;
+    rlen = 0;
+    return(0);
+}
+
+(**
+ * sqlRead:
+ * @context: the read context
+ * @buffer: where to store data
+ * @len: number of bytes to read
+ *
+ * Implement an sql: query read.
+ *
+ * Returns the number of bytes read or -1 in case of error
+ *)
+function sqlRead(context: pointer; buffer: pchar; len: cint): cint; cdecl;
+begin
+end;
+{
+   const char *ptr = (const char *) context;
+
+   if ((context == NULL) || (buffer == NULL) || (len < 0))
+       return(-1);
+
+   if (len > rlen) len = rlen;
+   memcpy(buffer, ptr, len);
+   rlen -= len;
+   return(len);
+}
+
+
+var
+  doc: xmlDocPtr;
+
+begin
+  (*
+   * this initialize the library and check potential ABI mismatches
+   * between the version it was compiled for and the actual shared
+   * library used.
+   *)
+  LIBXML_TEST_VERSION;
+
+  (*
+   * register the new I/O handlers
+   *)
+  if xmlRegisterInputCallbacks(@sqlMatch, @sqlOpen, @sqlRead, @sqlClose) < 0 then
+  begin
+    printfn('failed to register SQL handler');
+    halt(1);
+  end;
+
+  (*
+   * parse include into a document
+   *)
+  doc := xmlReadMemory(include, strlen(include), 'include.xml', nil, 0);
+  if doc = nil then
+  begin
+    printfn('failed to parse the including file');
+    halt(1);
+  end;
+
+  (*
+   * apply the XInclude process, this should trigger the I/O just
+   * registered.
+   *)
+  if xmlXIncludeProcess(doc) <= 0 then
+  begin
+    printfn('XInclude processing failed');
+    halt(1);
+  end;
+
+  (*
+   * save the output for checking to stdout
+   *)
+//  xmlDocDump(stdout, doc);
+
+  (*
+   * Free the document
+   *)
+  xmlFreeDoc(doc);
+
+  (*
+   * Cleanup function for the XML library.
+   *)
+  xmlCleanupParser();
+end.