diff options
author | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
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committer | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
commit | e5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch) | |
tree | d8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/cmd/con/xmr.c |
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/cmd/con/xmr.c')
-rwxr-xr-x | sys/src/cmd/con/xmr.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/sys/src/cmd/con/xmr.c b/sys/src/cmd/con/xmr.c new file mode 100755 index 000000000..3f57610ef --- /dev/null +++ b/sys/src/cmd/con/xmr.c @@ -0,0 +1,182 @@ +#include <u.h> +#include <libc.h> + +enum { + Soh= 0x1, + Eot= 0x4, + Ack= 0x6, + Nak= 0x15, + Cancel= 0x18, +}; + +int notifyf(void*, char*); +int readupto(uchar*, int); +int receive(int, uchar); +void send(int); + +int debug, dfd; + +void +main(int argc, char **argv) +{ + int fd; + uchar seqno; + ulong bytes; + + ARGBEGIN { + case 'd': + dfd = 2; + debug = 1; + break; + } ARGEND + + if(argc != 1){ + fprint(2, "usage: xmr filename\n"); + exits("usage"); + } + fd = open("/dev/consctl", OWRITE); + if(fd >= 0) + write(fd, "rawon", 5); + fd = create(argv[0], ORDWR, 0666); + if(fd < 0){ + perror("xmr: create"); + exits("create"); + } + + atnotify(notifyf, 1); + send(Nak); + + /* + * keep receiving till the other side gives up + */ + bytes = 0; + for(seqno = 1; ; seqno++){ + if(receive(fd, seqno) == -1) + break; + bytes += 128; + } + fprint(2, "xmr: received %ld bytes\n", bytes); + exits(0); +} + +void +send(int byte) +{ + uchar c; + + c = byte; + if(write(1, &c, 1) != 1){ + fprint(2, "xmr: hungup\n"); + exits("hangup"); + } +} + +int +readupto(uchar *a, int len) +{ + int n; + int sofar; + + for(sofar = 0; sofar < len; sofar += n){ + n = read(0, a, len-sofar); + if(n <= 0){ + send(Nak); + return sofar; + } + if(*a == Eot || *a == Cancel) + return sofar + n; + a += n; + } + return sofar; + +} + +int +receive(int fd, uchar seqno) +{ + uchar buf[128+4]; + uchar sum; + uchar *p; + int n; + int tries; + int have; + + for(have = 0, tries = 0;; tries++){ + if(debug) + fprint(dfd, "have == %d\n", have); + if(tries > 10){ + fprint(2, "xmr: timed out\n"); + if(debug) + close(dfd); + exits("timeout"); + } + + /* try to gather up a block */ + alarm(15*1000); + n = readupto(&buf[have], 132-have); + alarm(0); + have += n; + if(have){ + switch(buf[0]){ + case Eot: + send(Ack); + return -1; + case Cancel: + fprint(2, "xmr: transfer aborted by sender\n"); + exits("cancel"); + } + } + if(have != 132) + continue; + + /* checksum */ + for(p = buf, sum = 0; p < &buf[128+3]; p++) + sum += *p; + + /* If invalid block, resynchronize */ + if(buf[0] != Soh || buf[2] != (255-buf[1]) || sum != buf[131]){ + if(debug){ + fprint(dfd, "resync %2.2ux %d %d %ux %ux\n", buf[0], + buf[1], buf[2], sum, buf[131]); + write(dfd, (char*)buf+3, 128); + fprint(dfd, "\n"); + } + p = memchr(buf+1, Soh, 131); + if(p){ + have = 132-(p-buf); + memmove(buf, p, have); + } else + have = 0; + continue; + } + + /* it's probably a real block, so dump it if there's an error */ + have = 0; + + /* if this is the last block, ack */ + if(buf[1] == seqno-1){ + tries = 0; + send(Ack); + }else if(buf[1] == seqno){ + if(debug) + fprint(dfd, "Ack\n"); + send(Ack); + if(write(fd, buf+3, 128) != 128){ + fprint(2, "xmr: abort, error writing file\n"); + exits("write"); + } + return 0; + } else { + send(Nak); + } + } +} + +int +notifyf(void *a, char *msg) +{ + USED(a); + if(strcmp(msg, "alarm") == 0) + return 1; + return 0; +} |