1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/* Copyright (C) 2008 Free Software Foundation, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 3 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
/* Exercise `scm_c_read ()' and the port type API. Verify assumptions that
can be made by port type implementations. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <libguile.h>
#include <assert.h>
/* Size of our port's internal buffer. */
#define PORT_BUFFER_SIZE 1024
/* Return a new port of type PORT_TYPE. */
static inline SCM
make_port (scm_t_bits port_type)
{
SCM port;
char *c_buffer;
scm_t_port *c_port;
c_buffer = scm_gc_calloc (PORT_BUFFER_SIZE, "custom-port-buffer");
port = scm_new_port_table_entry (port_type);
/* Associate C_BUFFER with PORT, for test purposes. */
SCM_SETSTREAM (port, (scm_t_bits) c_buffer);
/* Use C_BUFFER as PORT's internal buffer. */
c_port = SCM_PTAB_ENTRY (port);
c_port->read_pos = c_port->read_buf = (unsigned char *) c_buffer;
c_port->read_end = (unsigned char *) c_buffer + PORT_BUFFER_SIZE;
c_port->read_buf_size = PORT_BUFFER_SIZE;
/* Mark PORT as open and readable. */
SCM_SET_CELL_TYPE (port, port_type | SCM_OPN | SCM_RDNG);
return port;
}
/* Read one byte from PORT. */
static int
fill_input (SCM port)
{
int result;
scm_t_port *c_port = SCM_PTAB_ENTRY (port);
/* Make sure that C_PORT's internal buffer wasn't changed behind our back.
See http://lists.gnu.org/archive/html/guile-devel/2008-11/msg00042.html
for an example where this assumption matters. */
assert (c_port->read_buf == (unsigned char *) SCM_STREAM (port));
assert (c_port->read_buf_size == PORT_BUFFER_SIZE);
if (c_port->read_pos >= c_port->read_end)
result = EOF;
else
result = (int) *c_port->read_pos++;
return result;
}
/* Return true (non-zero) if BUF contains only zeros. */
static inline int
zeroed_buffer_p (const char *buf, size_t len)
{
size_t i;
for (i = 0; i < len; i++)
if (buf[i] != 0)
return 0;
return 1;
}
/* Run the test. */
static void *
do_start (void *arg)
{
SCM port;
scm_t_bits port_type;
char buffer[PORT_BUFFER_SIZE + (PORT_BUFFER_SIZE / 2)];
size_t read, last_read;
port_type = scm_make_port_type ("custom-input-port", fill_input, NULL);
port = make_port (port_type);
read = 0;
do
{
last_read = scm_c_read (port, &buffer[read], 123);
assert (last_read <= 123);
assert (zeroed_buffer_p (&buffer[read], last_read));
read += last_read;
}
while (last_read > 0 && read < sizeof (buffer));
/* We shouldn't be able to read more than what's in PORT's buffer. */
assert (read == PORT_BUFFER_SIZE);
return NULL;
}
int
main (int argc, char *argv[])
{
scm_with_guile (do_start, NULL);
return 0;
}
|
