1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24 /* <DESC>
25 * Show how CURLOPT_DEBUGFUNCTION can be used.
26 * </DESC>
27 */
28 #include <stdio.h>
29 #include <curl/curl.h>
30
31 struct data {
32 char trace_ascii; /* 1 or 0 */
33 };
34
35 static
dump(const char * text,FILE * stream,unsigned char * ptr,size_t size,char nohex)36 void dump(const char *text,
37 FILE *stream, unsigned char *ptr, size_t size,
38 char nohex)
39 {
40 size_t i;
41 size_t c;
42
43 unsigned int width = 0x10;
44
45 if(nohex)
46 /* without the hex output, we can fit more on screen */
47 width = 0x40;
48
49 fprintf(stream, "%s, %10.10lu bytes (0x%8.8lx)\n",
50 text, (unsigned long)size, (unsigned long)size);
51
52 for(i = 0; i < size; i += width) {
53
54 fprintf(stream, "%4.4lx: ", (unsigned long)i);
55
56 if(!nohex) {
57 /* hex not disabled, show it */
58 for(c = 0; c < width; c++)
59 if(i + c < size)
60 fprintf(stream, "%02x ", ptr[i + c]);
61 else
62 fputs(" ", stream);
63 }
64
65 for(c = 0; (c < width) && (i + c < size); c++) {
66 /* check for 0D0A; if found, skip past and start a new line of output */
67 if(nohex && (i + c + 1 < size) && ptr[i + c] == 0x0D &&
68 ptr[i + c + 1] == 0x0A) {
69 i += (c + 2 - width);
70 break;
71 }
72 fprintf(stream, "%c",
73 (ptr[i + c] >= 0x20) && (ptr[i + c] < 0x80) ? ptr[i + c] : '.');
74 /* check again for 0D0A, to avoid an extra \n if it's at width */
75 if(nohex && (i + c + 2 < size) && ptr[i + c + 1] == 0x0D &&
76 ptr[i + c + 2] == 0x0A) {
77 i += (c + 3 - width);
78 break;
79 }
80 }
81 fputc('\n', stream); /* newline */
82 }
83 fflush(stream);
84 }
85
86 static
my_trace(CURL * handle,curl_infotype type,char * data,size_t size,void * userp)87 int my_trace(CURL *handle, curl_infotype type,
88 char *data, size_t size,
89 void *userp)
90 {
91 struct data *config = (struct data *)userp;
92 const char *text;
93 (void)handle; /* prevent compiler warning */
94
95 switch(type) {
96 case CURLINFO_TEXT:
97 fprintf(stderr, "== Info: %s", data);
98 return 0;
99 case CURLINFO_HEADER_OUT:
100 text = "=> Send header";
101 break;
102 case CURLINFO_DATA_OUT:
103 text = "=> Send data";
104 break;
105 case CURLINFO_SSL_DATA_OUT:
106 text = "=> Send SSL data";
107 break;
108 case CURLINFO_HEADER_IN:
109 text = "<= Recv header";
110 break;
111 case CURLINFO_DATA_IN:
112 text = "<= Recv data";
113 break;
114 case CURLINFO_SSL_DATA_IN:
115 text = "<= Recv SSL data";
116 break;
117 default: /* in case a new one is introduced to shock us */
118 return 0;
119 }
120
121 dump(text, stderr, (unsigned char *)data, size, config->trace_ascii);
122 return 0;
123 }
124
main(void)125 int main(void)
126 {
127 CURL *curl;
128 CURLcode res;
129 struct data config;
130
131 config.trace_ascii = 1; /* enable ASCII tracing */
132
133 curl = curl_easy_init();
134 if(curl) {
135 curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, my_trace);
136 curl_easy_setopt(curl, CURLOPT_DEBUGDATA, &config);
137
138 /* the DEBUGFUNCTION has no effect until we enable VERBOSE */
139 curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
140
141 /* example.com is redirected, so we tell libcurl to follow redirection */
142 curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
143
144 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
145 res = curl_easy_perform(curl);
146 /* Check for errors */
147 if(res != CURLE_OK)
148 fprintf(stderr, "curl_easy_perform() failed: %s\n",
149 curl_easy_strerror(res));
150
151 /* always cleanup */
152 curl_easy_cleanup(curl);
153 }
154 return 0;
155 }
156
