xref: /freebsd/contrib/expat/examples/outline.c (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
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 
54 static void XMLCALL
55 startElement(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 
72 static void XMLCALL
73 endElement(void *userData, const XML_Char *name) {
74   int *const depthPtr = (int *)userData;
75   (void)name;
76 
77   *depthPtr -= 1;
78 }
79 
80 int
81 main(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