Tiny SNTP(NTP) Client
Dependencies: EthernetNetIf mbed
TinySNTP.cpp@0:41e7cfdbd23a, 2011-07-21 (annotated)
- Committer:
- okini3939
- Date:
- Thu Jul 21 17:53:11 2011 +0000
- Revision:
- 0:41e7cfdbd23a
- Child:
- 1:d3c1871be1e9
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
okini3939 | 0:41e7cfdbd23a | 1 | /* |
okini3939 | 0:41e7cfdbd23a | 2 | * mbed Tiny SNTP(NTP) Client |
okini3939 | 0:41e7cfdbd23a | 3 | * Copyright (c) 2011 Hiroshi Suga |
okini3939 | 0:41e7cfdbd23a | 4 | * Released under the MIT License: http://mbed.org/license/mit |
okini3939 | 0:41e7cfdbd23a | 5 | */ |
okini3939 | 0:41e7cfdbd23a | 6 | |
okini3939 | 0:41e7cfdbd23a | 7 | /** @file |
okini3939 | 0:41e7cfdbd23a | 8 | * @brief Tiny DNS Resolver |
okini3939 | 0:41e7cfdbd23a | 9 | */ |
okini3939 | 0:41e7cfdbd23a | 10 | |
okini3939 | 0:41e7cfdbd23a | 11 | #include "mbed.h" |
okini3939 | 0:41e7cfdbd23a | 12 | #include "EthernetNetIf.h" |
okini3939 | 0:41e7cfdbd23a | 13 | #include "UDPSocket.h" |
okini3939 | 0:41e7cfdbd23a | 14 | #include "DNSRequest.h" |
okini3939 | 0:41e7cfdbd23a | 15 | #include "TinySNTP.h" |
okini3939 | 0:41e7cfdbd23a | 16 | |
okini3939 | 0:41e7cfdbd23a | 17 | // host to network short |
okini3939 | 0:41e7cfdbd23a | 18 | #define htons( x ) ( (( (x) << 8 ) & 0xFF00) | (( (x) >> 8 ) & 0x00FF) ) |
okini3939 | 0:41e7cfdbd23a | 19 | #define ntohs( x ) htons(x) |
okini3939 | 0:41e7cfdbd23a | 20 | // host to network long |
okini3939 | 0:41e7cfdbd23a | 21 | #define htonl( x ) ( (( (x) << 24 ) & 0xFF000000) \ |
okini3939 | 0:41e7cfdbd23a | 22 | | (( (x) << 8 ) & 0x00FF0000) \ |
okini3939 | 0:41e7cfdbd23a | 23 | | (( (x) >> 8 ) & 0x0000FF00) \ |
okini3939 | 0:41e7cfdbd23a | 24 | | (( (x) >> 24 ) & 0x000000FF) ) |
okini3939 | 0:41e7cfdbd23a | 25 | #define ntohl( x ) htonl(x) |
okini3939 | 0:41e7cfdbd23a | 26 | |
okini3939 | 0:41e7cfdbd23a | 27 | static UDPSocket *sntp; |
okini3939 | 0:41e7cfdbd23a | 28 | static volatile unsigned long sntptime; |
okini3939 | 0:41e7cfdbd23a | 29 | extern EthernetNetIf eth; |
okini3939 | 0:41e7cfdbd23a | 30 | |
okini3939 | 0:41e7cfdbd23a | 31 | int createSntpRequest (char *buf) { |
okini3939 | 0:41e7cfdbd23a | 32 | struct SNTPPacket *sntp; |
okini3939 | 0:41e7cfdbd23a | 33 | |
okini3939 | 0:41e7cfdbd23a | 34 | sntp = (struct SNTPPacket *)buf; |
okini3939 | 0:41e7cfdbd23a | 35 | memset(sntp, 0, sizeof(struct SNTPPacket)); |
okini3939 | 0:41e7cfdbd23a | 36 | sntp->info = 0x1b; // Ver.3, client |
okini3939 | 0:41e7cfdbd23a | 37 | sntp->txTm_s = htonl(NTP_TIMESTAMP_DELTA + time(NULL)); |
okini3939 | 0:41e7cfdbd23a | 38 | |
okini3939 | 0:41e7cfdbd23a | 39 | return sizeof(struct SNTPPacket); |
okini3939 | 0:41e7cfdbd23a | 40 | } |
okini3939 | 0:41e7cfdbd23a | 41 | |
okini3939 | 0:41e7cfdbd23a | 42 | int getSntpResponse (const char *buf, uint32_t *tim) { |
okini3939 | 0:41e7cfdbd23a | 43 | struct SNTPPacket *sntp; |
okini3939 | 0:41e7cfdbd23a | 44 | uint32_t now; |
okini3939 | 0:41e7cfdbd23a | 45 | // long int delay, offset; |
okini3939 | 0:41e7cfdbd23a | 46 | |
okini3939 | 0:41e7cfdbd23a | 47 | sntp = (struct SNTPPacket *)buf; |
okini3939 | 0:41e7cfdbd23a | 48 | if ((sntp->info & 0x3f) == 0x1c || (sntp->info & 0x3f) == 0x24) { |
okini3939 | 0:41e7cfdbd23a | 49 | // Ver.3or4, Server |
okini3939 | 0:41e7cfdbd23a | 50 | |
okini3939 | 0:41e7cfdbd23a | 51 | now = htonl(NTP_TIMESTAMP_DELTA + time(NULL)); |
okini3939 | 0:41e7cfdbd23a | 52 | /* |
okini3939 | 0:41e7cfdbd23a | 53 | delay = (now - sntp->origTm_s) - (sntp->rxTm_s - sntp->txTm_s); |
okini3939 | 0:41e7cfdbd23a | 54 | offset = ((sntp->rxTm_s - sntp->origTm_s) + (sntp->txTm_s - now)); |
okini3939 | 0:41e7cfdbd23a | 55 | |
okini3939 | 0:41e7cfdbd23a | 56 | *tim = ntohl(sntp->txTm_s) - NTP_TIMESTAMP_DELTA + (delay / 2); |
okini3939 | 0:41e7cfdbd23a | 57 | */ |
okini3939 | 0:41e7cfdbd23a | 58 | *tim = ntohl(sntp->txTm_s) - NTP_TIMESTAMP_DELTA; |
okini3939 | 0:41e7cfdbd23a | 59 | #ifdef DEBUG |
okini3939 | 0:41e7cfdbd23a | 60 | printf("now %08x\r\n", ntohl(now)); |
okini3939 | 0:41e7cfdbd23a | 61 | printf("ref %08x\r\n", ntohl(sntp->refTm_s)); |
okini3939 | 0:41e7cfdbd23a | 62 | printf("orig %08x\r\n", ntohl(sntp->origTm_s)); |
okini3939 | 0:41e7cfdbd23a | 63 | printf("rx %08x\r\n", ntohl(sntp->rxTm_s)); |
okini3939 | 0:41e7cfdbd23a | 64 | printf("tx %08x\r\n", ntohl(sntp->txTm_s)); |
okini3939 | 0:41e7cfdbd23a | 65 | // printf("delay %d / offset %d\r\n", delay, offset); |
okini3939 | 0:41e7cfdbd23a | 66 | #endif |
okini3939 | 0:41e7cfdbd23a | 67 | return 0; |
okini3939 | 0:41e7cfdbd23a | 68 | } |
okini3939 | 0:41e7cfdbd23a | 69 | |
okini3939 | 0:41e7cfdbd23a | 70 | return -1; |
okini3939 | 0:41e7cfdbd23a | 71 | } |
okini3939 | 0:41e7cfdbd23a | 72 | |
okini3939 | 0:41e7cfdbd23a | 73 | void isr_sntp (UDPSocketEvent e) { |
okini3939 | 0:41e7cfdbd23a | 74 | char buf[100]; |
okini3939 | 0:41e7cfdbd23a | 75 | Host dsthost; |
okini3939 | 0:41e7cfdbd23a | 76 | int len; |
okini3939 | 0:41e7cfdbd23a | 77 | |
okini3939 | 0:41e7cfdbd23a | 78 | if (e == UDPSOCKET_READABLE) { |
okini3939 | 0:41e7cfdbd23a | 79 | // recv responce; |
okini3939 | 0:41e7cfdbd23a | 80 | len = sntp->recvfrom(buf, sizeof(buf), &dsthost); |
okini3939 | 0:41e7cfdbd23a | 81 | #ifdef DEBUG |
okini3939 | 0:41e7cfdbd23a | 82 | for (int i = 0; i < len; i ++) { |
okini3939 | 0:41e7cfdbd23a | 83 | printf(" %02x", (unsigned char)buf[i]); |
okini3939 | 0:41e7cfdbd23a | 84 | } |
okini3939 | 0:41e7cfdbd23a | 85 | puts("\r"); |
okini3939 | 0:41e7cfdbd23a | 86 | #endif |
okini3939 | 0:41e7cfdbd23a | 87 | if (len >= sizeof(struct SNTPPacket)) { |
okini3939 | 0:41e7cfdbd23a | 88 | getSntpResponse(buf, (uint32_t*)&sntptime); |
okini3939 | 0:41e7cfdbd23a | 89 | } |
okini3939 | 0:41e7cfdbd23a | 90 | } |
okini3939 | 0:41e7cfdbd23a | 91 | } |
okini3939 | 0:41e7cfdbd23a | 92 | |
okini3939 | 0:41e7cfdbd23a | 93 | int ntpdate (const char* name, uint32_t *tim) { |
okini3939 | 0:41e7cfdbd23a | 94 | UDPSocketErr err; |
okini3939 | 0:41e7cfdbd23a | 95 | Host myhost, sntphost; |
okini3939 | 0:41e7cfdbd23a | 96 | char buf[100]; |
okini3939 | 0:41e7cfdbd23a | 97 | int i, len; |
okini3939 | 0:41e7cfdbd23a | 98 | DNSRequest dns; |
okini3939 | 0:41e7cfdbd23a | 99 | DNSRequestErr dnsErr; |
okini3939 | 0:41e7cfdbd23a | 100 | |
okini3939 | 0:41e7cfdbd23a | 101 | sntptime = 0; |
okini3939 | 0:41e7cfdbd23a | 102 | sntp = new UDPSocket; |
okini3939 | 0:41e7cfdbd23a | 103 | sntp->setOnEvent(isr_sntp); |
okini3939 | 0:41e7cfdbd23a | 104 | |
okini3939 | 0:41e7cfdbd23a | 105 | // bind |
okini3939 | 0:41e7cfdbd23a | 106 | myhost.setIp(eth.getIp()); |
okini3939 | 0:41e7cfdbd23a | 107 | myhost.setPort(NTP_SRC_PORT); |
okini3939 | 0:41e7cfdbd23a | 108 | err = sntp->bind(myhost); |
okini3939 | 0:41e7cfdbd23a | 109 | if (err != UDPSOCKET_OK) goto exit; |
okini3939 | 0:41e7cfdbd23a | 110 | |
okini3939 | 0:41e7cfdbd23a | 111 | // send request |
okini3939 | 0:41e7cfdbd23a | 112 | sntphost.setName(name); |
okini3939 | 0:41e7cfdbd23a | 113 | sntphost.setPort(NTP_PORT); |
okini3939 | 0:41e7cfdbd23a | 114 | dnsErr = dns.resolve(&sntphost); |
okini3939 | 0:41e7cfdbd23a | 115 | if (dnsErr != DNS_OK) goto exit; |
okini3939 | 0:41e7cfdbd23a | 116 | len = createSntpRequest(buf); |
okini3939 | 0:41e7cfdbd23a | 117 | #ifdef DEBUG |
okini3939 | 0:41e7cfdbd23a | 118 | for (int i = 0; i < len; i ++) { |
okini3939 | 0:41e7cfdbd23a | 119 | printf(" %02x", (unsigned char)buf[i]); |
okini3939 | 0:41e7cfdbd23a | 120 | } |
okini3939 | 0:41e7cfdbd23a | 121 | puts("\r"); |
okini3939 | 0:41e7cfdbd23a | 122 | #endif |
okini3939 | 0:41e7cfdbd23a | 123 | sntp->sendto(buf, len, &sntphost); |
okini3939 | 0:41e7cfdbd23a | 124 | |
okini3939 | 0:41e7cfdbd23a | 125 | // wait responce |
okini3939 | 0:41e7cfdbd23a | 126 | for (i = 0; i < NTP_TIMEOUT / 10; i ++) { |
okini3939 | 0:41e7cfdbd23a | 127 | if (sntptime) { |
okini3939 | 0:41e7cfdbd23a | 128 | *tim = sntptime; |
okini3939 | 0:41e7cfdbd23a | 129 | break; |
okini3939 | 0:41e7cfdbd23a | 130 | } |
okini3939 | 0:41e7cfdbd23a | 131 | if (i % 500 == 499) { |
okini3939 | 0:41e7cfdbd23a | 132 | sntp->sendto(buf, len, &sntphost); |
okini3939 | 0:41e7cfdbd23a | 133 | } |
okini3939 | 0:41e7cfdbd23a | 134 | Net::poll(); |
okini3939 | 0:41e7cfdbd23a | 135 | wait_ms(10); |
okini3939 | 0:41e7cfdbd23a | 136 | } |
okini3939 | 0:41e7cfdbd23a | 137 | |
okini3939 | 0:41e7cfdbd23a | 138 | exit: |
okini3939 | 0:41e7cfdbd23a | 139 | sntp->resetOnEvent(); |
okini3939 | 0:41e7cfdbd23a | 140 | delete sntp; |
okini3939 | 0:41e7cfdbd23a | 141 | |
okini3939 | 0:41e7cfdbd23a | 142 | return sntptime ? 0 : -1; |
okini3939 | 0:41e7cfdbd23a | 143 | } |