1/* Read an XML document from standard input and print an element
2   outline on standard output.
3   Must be used with Expat compiled for UTF-8 output.
4                            __  __            _
5                         ___\ \/ /_ __   __ _| |_
6                        / _ \\  /| '_ \ / _` | __|
7                       |  __//  \| |_) | (_| | |_
8                        \___/_/\_\ .__/ \__,_|\__|
9                                 |_| XML parser
10
11   Copyright (c) 2000      Clark Cooper <coopercc@users.sourceforge.net>
12   Copyright (c) 2001-2003 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
13   Copyright (c) 2005-2007 Steven Solie <steven@solie.ca>
14   Copyright (c) 2005-2006 Karl Waclawek <karl@waclawek.net>
15   Copyright (c) 2016-2022 Sebastian Pipping <sebastian@pipping.org>
16   Copyright (c) 2017      Rhodri James <rhodri@wildebeest.org.uk>
17   Licensed under the MIT license:
18
19   Permission is  hereby granted,  free of charge,  to any  person obtaining
20   a  copy  of  this  software   and  associated  documentation  files  (the
21   "Software"),  to  deal in  the  Software  without restriction,  including
22   without  limitation the  rights  to use,  copy,  modify, merge,  publish,
23   distribute, sublicense, and/or sell copies of the Software, and to permit
24   persons  to whom  the Software  is  furnished to  do so,  subject to  the
25   following conditions:
26
27   The above copyright  notice and this permission notice  shall be included
28   in all copies or substantial portions of the Software.
29
30   THE  SOFTWARE  IS  PROVIDED  "AS  IS",  WITHOUT  WARRANTY  OF  ANY  KIND,
31   EXPRESS  OR IMPLIED,  INCLUDING  BUT  NOT LIMITED  TO  THE WARRANTIES  OF
32   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
33   NO EVENT SHALL THE AUTHORS OR  COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
34   DAMAGES OR  OTHER LIABILITY, WHETHER  IN AN  ACTION OF CONTRACT,  TORT OR
35   OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
36   USE OR OTHER DEALINGS IN THE SOFTWARE.
37*/
38
39#include <stdio.h>
40#include <expat.h>
41
42#ifdef XML_LARGE_SIZE
43#  define XML_FMT_INT_MOD "ll"
44#else
45#  define XML_FMT_INT_MOD "l"
46#endif
47
48#ifdef XML_UNICODE_WCHAR_T
49#  define XML_FMT_STR "ls"
50#else
51#  define XML_FMT_STR "s"
52#endif
53
54static void XMLCALL
55startElement(void *userData, const XML_Char *name, const XML_Char **atts) {
56  int i;
57  int *const depthPtr = (int *)userData;
58
59  for (i = 0; i < *depthPtr; i++)
60    printf("  ");
61
62  printf("%" XML_FMT_STR, name);
63
64  for (i = 0; atts[i]; i += 2) {
65    printf(" %" XML_FMT_STR "='%" XML_FMT_STR "'", atts[i], atts[i + 1]);
66  }
67
68  printf("\n");
69  *depthPtr += 1;
70}
71
72static void XMLCALL
73endElement(void *userData, const XML_Char *name) {
74  int *const depthPtr = (int *)userData;
75  (void)name;
76
77  *depthPtr -= 1;
78}
79
80int
81main(void) {
82  XML_Parser parser = XML_ParserCreate(NULL);
83  int done;
84  int depth = 0;
85
86  if (! parser) {
87    fprintf(stderr, "Couldn't allocate memory for parser\n");
88    return 1;
89  }
90
91  XML_SetUserData(parser, &depth);
92  XML_SetElementHandler(parser, startElement, endElement);
93
94  do {
95    void *const buf = XML_GetBuffer(parser, BUFSIZ);
96    if (! buf) {
97      fprintf(stderr, "Couldn't allocate memory for buffer\n");
98      XML_ParserFree(parser);
99      return 1;
100    }
101
102    const size_t len = fread(buf, 1, BUFSIZ, stdin);
103
104    if (ferror(stdin)) {
105      fprintf(stderr, "Read error\n");
106      XML_ParserFree(parser);
107      return 1;
108    }
109
110    done = feof(stdin);
111
112    if (XML_ParseBuffer(parser, (int)len, done) == XML_STATUS_ERROR) {
113      fprintf(stderr,
114              "Parse error at line %" XML_FMT_INT_MOD "u:\n%" XML_FMT_STR "\n",
115              XML_GetCurrentLineNumber(parser),
116              XML_ErrorString(XML_GetErrorCode(parser)));
117      XML_ParserFree(parser);
118      return 1;
119    }
120  } while (! done);
121
122  XML_ParserFree(parser);
123  return 0;
124}
125