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
132
133
134
135
136
137
138
|
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <gsmd/usock.h>
#include <libgsmd/libgsmd.h>
#include "lgsm_internals.h"
static int lgsm_get_packet(struct lgsm_handle *lh)
{
static char buf[GSMD_MSGSIZE_MAX];
struct gsmd_msg_hdr *hdr = (struct gsmd_msg_hdr *) buf;
int rc = read(lh->fd, buf, sizeof(buf));
if (rc <= 0)
return rc;
if (hdr->version != GSMD_PROTO_VERSION)
return -EINVAL;
switch (hdr->msg_type) {
case GSMD_MSG_PASSTHROUGH:
break;
default:
return -EINVAL;
}
return 0;
}
static int lgsm_open_backend(struct lgsm_handle *lh, const char *device)
{
int rc;
if (!strcmp(device, LGSMD_DEVICE_GSMD)) {
struct sockaddr_un sun;
/* use unix domain socket to gsm daemon */
lh->fd = socket(PF_UNIX, GSMD_UNIX_SOCKET_TYPE, 0);
if (lh->fd < 0)
return lh->fd;
memset(&sun, 0, sizeof(sun));
sun.sun_family = AF_UNIX;
memcpy(sun.sun_path, GSMD_UNIX_SOCKET, sizeof(GSMD_UNIX_SOCKET));
rc = connect(lh->fd, (struct sockaddr *)&sun, sizeof(sun));
if (rc < 0) {
close(lh->fd);
lh->fd = -1;
return rc;
}
} else
return -EINVAL;
return 0;
}
/* handle a packet that was received on the gsmd socket */
int lgsm_handle_packet(struct lgsm_handle *lh, char *buf, int len)
{
struct gsmd_msg_hdr *gmh = (struct gsmd_msg_hdr *)buf;
if (len < sizeof(*gmh))
return -EINVAL;
if (len - sizeof(*gmh) < gmh->len)
return -EINVAL;
if (gmh->msg_type >= __NUM_GSMD_MSGS)
return -EINVAL;
return lh->handler[gmh->msg_type](lh, gmh);
}
/* blocking read and processing of packets until packet matching 'id' is found */
int lgsm_blocking_wait_packet(struct lgsm_handle *lh, u_int16_t id,
struct gsmd_msg_hdr *gmh, int rlen)
{
int rc;
fd_set readset;
FD_ZERO(&readset);
while (1) {
FD_SET(lh->fd, &readset);
rc = select(lh->fd+1, &readset, NULL, NULL, NULL);
if (rc <= 0)
return rc;
rc = read(lh->fd, (char *)gmh, rlen);
if (rc <= 0)
return rc;
if (gmh->id == id) {
/* we've found the matching packet, return to calling function */
return rc;
} else
rc = lgsm_handle_packet(lh, (char *)gmh, rc);
}
}
int lgsm_fd(struct lgsm_handle *lh)
{
return lh->fd;
}
struct lgsm_handle *lgsm_init(const char *device)
{
struct lgsm_handle *lh = malloc(sizeof(*lh));
memset(lh, 0, sizeof(*lh));
lh->fd = -1;
if (lgsm_open_backend(lh, device) < 0) {
free(lh);
return NULL;
}
/* send some initial commands, such as ATV1 (verbose response)
* and +CRC=1 (which we currently require!) */
return lh;
}
int lgsm_exit(struct lgsm_handle *lh)
{
free(lh);
return 0;
}
|
