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simpler sml_transport_read method

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This commit is contained in:
Juri Glass 2012-06-07 21:52:19 +02:00
parent 12659704bb
commit 6ec77f5aef
1 changed files with 82 additions and 2 deletions
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84
sml/src/sml_transport.c
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@ -28,6 +28,86 @@
#define MC_SML_BUFFER_LEN 8096
unsigned char esc_seq[] = {0x1b, 0x1b, 0x1b, 0x1b};
unsigned char start_seq[] = {0x1b, 0x1b, 0x1b, 0x1b, 0x01, 0x01, 0x01, 0x01};
unsigned char end_seq[] = {0x1b, 0x1b, 0x1b, 0x1b, 0x1a};
size_t sml_read(int fd, fd_set *set, unsigned char *buffer, size_t len) {
size_t r, tr = 0;
while (tr < len) {
select(fd + 1, set, 0, 0, 0);
if (FD_ISSET(fd, set)) {
r = read(fd, &(buffer[tr]), len - tr);
if (r < 0) continue;
tr += r;
}
}
return tr;
}
size_t sml_transport_read(int fd, unsigned char *buffer, size_t max_len) {
fd_set readfds;
FD_ZERO(&readfds);
FD_SET(fd, &readfds);
unsigned char buf[max_len];
memset(buf, 0, max_len);
unsigned int len = 0;
while (len < 8) {
sml_read(fd, &readfds, &(buf[len]), 1);
if ((buf[len] == 0x1b && len < 4) || (buf[len] == 0x01 && len >= 4)) {
len++;
}
else {
len = 0;
}
}
// found start sequence
while (len < max_len) {
sml_read(fd, &readfds, &(buf[len]), 4);
if (memcmp(&buf[len], esc_seq, 4) == 0) {
// found esc sequence
len += 4;
sml_read(fd, &readfds, &(buf[len]), 4);
if (buf[len] == 0x1a) {
// found end sequence
len += 4;
memcpy(buffer, &(buf[0]), len);
return len;
}
else {
// dont read other escaped sequences yet
printf("error: unrecognized sequence");
return -1;
}
}
len += 4;
}
return -1;
}
/*
size_t sml_transport_read(int fd, unsigned char *buffer, size_t max_len) {
fd_set readfds;
FD_ZERO(&readfds);
@ -108,6 +188,8 @@ size_t sml_transport_read(int fd, unsigned char *buffer, size_t max_len) {
return -1;
}
*/
void sml_transport_listen(int fd, void (*sml_transport_receiver)(unsigned char *buffer, size_t buffer_len)) {
unsigned char buffer[MC_SML_BUFFER_LEN];
size_t bytes;
@ -122,8 +204,6 @@ void sml_transport_listen(int fd, void (*sml_transport_receiver)(unsigned char *
}
int sml_transport_write(int fd, sml_file *file) {
unsigned char start_seq[] = {0x1b, 0x1b, 0x1b, 0x1b, 0x01, 0x01, 0x01, 0x01};
unsigned char end_seq[] = {0x1b, 0x1b, 0x1b, 0x1b, 0x1a};
sml_buffer *buf = file->buf;
buf->cursor = 0;