1 /* Copyright (C) 2008, 2014 Free Software Foundation, Inc.
2 *
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public License
5 * as published by the Free Software Foundation; either version 3 of
6 * the License, or (at your option) any later version.
7 *
8 * This library is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
12 *
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16 * 02110-1301 USA
17 */
18
19 /* Exercise `scm_c_read ()' and the port type API. Verify assumptions that
20 can be made by port type implementations. */
21
22 #ifdef HAVE_CONFIG_H
23 # include <config.h>
24 #endif
25
26 #undef NDEBUG
27
28 #include <libguile.h>
29 #include <assert.h>
30
31
32
33 /* Size of our port's internal buffer. */
34 #define PORT_BUFFER_SIZE 1024
35
36 struct custom_port
37 {
38 size_t pos;
39 size_t len;
40 char *buf;
41 };
42
43
44 /* Return a new port of type PORT_TYPE. */
45 static inline SCM
make_port(scm_t_port_type * port_type)46 make_port (scm_t_port_type *port_type)
47 {
48 struct custom_port *stream = scm_gc_typed_calloc (struct custom_port);
49
50 stream->pos = 0;
51 stream->len = PORT_BUFFER_SIZE;
52 stream->buf = scm_gc_calloc (stream->len, "custom-port-buffer");
53
54 return scm_c_make_port (port_type, SCM_RDNG, (scm_t_bits) stream);
55 }
56
57 static size_t
custom_port_read(SCM port,SCM dst,size_t start,size_t count)58 custom_port_read (SCM port, SCM dst, size_t start, size_t count)
59 {
60 size_t to_copy = count;
61 struct custom_port *stream = (void *) SCM_STREAM (port);
62
63 if (stream->pos + to_copy > stream->len)
64 to_copy = stream->len - stream->pos;
65
66 memcpy (SCM_BYTEVECTOR_CONTENTS (dst) + start,
67 stream->buf + stream->pos, to_copy);
68 stream->pos += to_copy;
69
70 return to_copy;
71 }
72
73 /* Return true (non-zero) if BUF contains only zeros. */
74 static inline int
zeroed_buffer_p(const char * buf,size_t len)75 zeroed_buffer_p (const char *buf, size_t len)
76 {
77 size_t i;
78
79 for (i = 0; i < len; i++)
80 if (buf[i] != 0)
81 return 0;
82
83 return 1;
84 }
85
86 /* Run the test. */
87 static void *
do_start(void * arg)88 do_start (void *arg)
89 {
90 SCM port;
91 scm_t_port_type *port_type;
92 char buffer[PORT_BUFFER_SIZE + (PORT_BUFFER_SIZE / 2)];
93 size_t read, last_read;
94
95 port_type = scm_make_port_type ("custom-input-port", custom_port_read, NULL);
96 port = make_port (port_type);
97
98 read = 0;
99 do
100 {
101 last_read = scm_c_read (port, &buffer[read], 123);
102 assert (last_read <= 123);
103 assert (zeroed_buffer_p (&buffer[read], last_read));
104
105 read += last_read;
106 }
107 while (last_read > 0 && read < sizeof (buffer));
108
109 /* We shouldn't be able to read more than what's in PORT's buffer. */
110 assert (read == PORT_BUFFER_SIZE);
111
112 return NULL;
113 }
114
115
116 int
main(int argc,char * argv[])117 main (int argc, char *argv[])
118 {
119 scm_with_guile (do_start, NULL);
120
121 return 0;
122 }
123