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) 2016-2022 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 SPDX-License-Identifier: MIT
42 */
43
44 #include <stdio.h>
45 #include <expat.h>
46
47 #ifdef XML_LARGE_SIZE
48 # define XML_FMT_INT_MOD "ll"
49 #else
50 # define XML_FMT_INT_MOD "l"
51 #endif
52
53 #ifdef XML_UNICODE_WCHAR_T
54 # define XML_FMT_STR "ls"
55 #else
56 # define XML_FMT_STR "s"
57 #endif
58
59 static void XMLCALL
startElement(void * userData,const XML_Char * name,const XML_Char ** atts)60 startElement(void *userData, const XML_Char *name, const XML_Char **atts) {
61 int i;
62 int *const depthPtr = (int *)userData;
63 (void)atts;
64
65 for (i = 0; i < *depthPtr; i++)
66 putchar('\t');
67 printf("%" XML_FMT_STR "\n", name);
68 *depthPtr += 1;
69 }
70
71 static void XMLCALL
endElement(void * userData,const XML_Char * name)72 endElement(void *userData, const XML_Char *name) {
73 int *const depthPtr = (int *)userData;
74 (void)name;
75
76 *depthPtr -= 1;
77 }
78
79 int
main(void)80 main(void) {
81 XML_Parser parser = XML_ParserCreate(NULL);
82 int done;
83 int depth = 0;
84
85 if (! parser) {
86 fprintf(stderr, "Couldn't allocate memory for parser\n");
87 return 1;
88 }
89
90 XML_SetUserData(parser, &depth);
91 XML_SetElementHandler(parser, startElement, endElement);
92
93 do {
94 void *const buf = XML_GetBuffer(parser, BUFSIZ);
95 if (! buf) {
96 fprintf(stderr, "Couldn't allocate memory for buffer\n");
97 XML_ParserFree(parser);
98 return 1;
99 }
100
101 const size_t len = fread(buf, 1, BUFSIZ, stdin);
102
103 if (ferror(stdin)) {
104 fprintf(stderr, "Read error\n");
105 XML_ParserFree(parser);
106 return 1;
107 }
108
109 done = feof(stdin);
110
111 if (XML_ParseBuffer(parser, (int)len, done) == XML_STATUS_ERROR) {
112 fprintf(stderr,
113 "Parse error at line %" XML_FMT_INT_MOD "u:\n%" XML_FMT_STR "\n",
114 XML_GetCurrentLineNumber(parser),
115 XML_ErrorString(XML_GetErrorCode(parser)));
116 XML_ParserFree(parser);
117 return 1;
118 }
119 } while (! done);
120
121 XML_ParserFree(parser);
122 return 0;
123 }
124