xref: /freebsd/contrib/expat/examples/elements.c (revision 1323ec571215a77ddd21294f0871979d5ad6b992)
1 /* This is simple demonstration of how to use expat. This program
2    reads an XML document from standard input and writes a line with
3    the name of each element to standard output indenting child
4    elements by one tab stop more than their parent element.
5    It must be used with Expat compiled for UTF-8 output.
6                             __  __            _
7                          ___\ \/ /_ __   __ _| |_
8                         / _ \\  /| '_ \ / _` | __|
9                        |  __//  \| |_) | (_| | |_
10                         \___/_/\_\ .__/ \__,_|\__|
11                                  |_| XML parser
12 
13    Copyright (c) 1997-2000 Thai Open Source Software Center Ltd
14    Copyright (c) 2001-2003 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
15    Copyright (c) 2004-2006 Karl Waclawek <karl@waclawek.net>
16    Copyright (c) 2005-2007 Steven Solie <steven@solie.ca>
17    Copyright (c) 2016-2019 Sebastian Pipping <sebastian@pipping.org>
18    Copyright (c) 2017      Rhodri James <rhodri@wildebeest.org.uk>
19    Copyright (c) 2019      Zhongyuan Zhou <zhouzhongyuan@huawei.com>
20    Licensed under the MIT license:
21 
22    Permission is  hereby granted,  free of charge,  to any  person obtaining
23    a  copy  of  this  software   and  associated  documentation  files  (the
24    "Software"),  to  deal in  the  Software  without restriction,  including
25    without  limitation the  rights  to use,  copy,  modify, merge,  publish,
26    distribute, sublicense, and/or sell copies of the Software, and to permit
27    persons  to whom  the Software  is  furnished to  do so,  subject to  the
28    following conditions:
29 
30    The above copyright  notice and this permission notice  shall be included
31    in all copies or substantial portions of the Software.
32 
33    THE  SOFTWARE  IS  PROVIDED  "AS  IS",  WITHOUT  WARRANTY  OF  ANY  KIND,
34    EXPRESS  OR IMPLIED,  INCLUDING  BUT  NOT LIMITED  TO  THE WARRANTIES  OF
35    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
36    NO EVENT SHALL THE AUTHORS OR  COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
37    DAMAGES OR  OTHER LIABILITY, WHETHER  IN AN  ACTION OF CONTRACT,  TORT OR
38    OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
39    USE OR OTHER DEALINGS IN THE SOFTWARE.
40 */
41 
42 #include <stdio.h>
43 #include <expat.h>
44 
45 #ifdef XML_LARGE_SIZE
46 #  define XML_FMT_INT_MOD "ll"
47 #else
48 #  define XML_FMT_INT_MOD "l"
49 #endif
50 
51 #ifdef XML_UNICODE_WCHAR_T
52 #  include <wchar.h>
53 #  define XML_FMT_STR "ls"
54 #else
55 #  define XML_FMT_STR "s"
56 #endif
57 
58 static void XMLCALL
59 startElement(void *userData, const XML_Char *name, const XML_Char **atts) {
60   int i;
61   int *depthPtr = (int *)userData;
62   (void)atts;
63 
64   for (i = 0; i < *depthPtr; i++)
65     putchar('\t');
66   printf("%" XML_FMT_STR "\n", name);
67   *depthPtr += 1;
68 }
69 
70 static void XMLCALL
71 endElement(void *userData, const XML_Char *name) {
72   int *depthPtr = (int *)userData;
73   (void)name;
74 
75   *depthPtr -= 1;
76 }
77 
78 int
79 main(int argc, char *argv[]) {
80   char buf[BUFSIZ];
81   XML_Parser parser = XML_ParserCreate(NULL);
82   int done;
83   int depth = 0;
84   (void)argc;
85   (void)argv;
86 
87   XML_SetUserData(parser, &depth);
88   XML_SetElementHandler(parser, startElement, endElement);
89   do {
90     size_t len = fread(buf, 1, sizeof(buf), stdin);
91     done = len < sizeof(buf);
92     if (XML_Parse(parser, buf, (int)len, done) == XML_STATUS_ERROR) {
93       fprintf(stderr, "%" XML_FMT_STR " at line %" XML_FMT_INT_MOD "u\n",
94               XML_ErrorString(XML_GetErrorCode(parser)),
95               XML_GetCurrentLineNumber(parser));
96       XML_ParserFree(parser);
97       return 1;
98     }
99   } while (! done);
100   XML_ParserFree(parser);
101   return 0;
102 }
103