/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-file-style: "k&r"; c-basic-offset: 2; -*-
Webduino, a simple Arduino web server
Copyright 2009 Ben Combee, Ran Talbott
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
#include
WebServer::WebServer(const char *urlPrefix, int port) :
m_server(port),
m_client(255),
m_urlPrefix(urlPrefix),
m_pushbackDepth(0),
m_cmdCount(0),
m_contentLength(0),
m_failureCmd(&defaultFailCmd),
m_defaultCmd(&defaultFailCmd)
{
}
void WebServer::begin()
{
m_server.begin();
}
void WebServer::setDefaultCommand(Command *cmd)
{
m_defaultCmd = cmd;
}
void WebServer::setFailureCommand(Command *cmd)
{
m_failureCmd = cmd;
}
void WebServer::addCommand(const char *verb, Command *cmd)
{
if (m_cmdCount < SIZE(m_commands))
{
m_commands[m_cmdCount].verb = verb;
m_commands[m_cmdCount++].cmd = cmd;
}
}
size_t WebServer::write(uint8_t ch)
{
return m_client.write(ch);
}
size_t WebServer::write(const char *str)
{
return m_client.write(str);
}
size_t WebServer::write(const uint8_t *buffer, size_t size)
{
return m_client.write(buffer, size);
}
size_t WebServer::write(const char *buffer, size_t length)
{
return m_client.write((const uint8_t *)buffer, length);
}
void WebServer::writeP(const prog_uchar *data, size_t length)
{
// copy data out of program memory into local storage, write out in
// chunks of 32 bytes to avoid extra short TCP/IP packets
uint8_t buffer[32];
size_t bufferEnd = 0;
while (length--)
{
if (bufferEnd == 32)
{
m_client.write(buffer, 32);
bufferEnd = 0;
}
buffer[bufferEnd++] = pgm_read_byte(data++);
}
if (bufferEnd > 0)
m_client.write(buffer, bufferEnd);
}
void WebServer::printP(const prog_uchar *str)
{
// copy data out of program memory into local storage, write out in
// chunks of 32 bytes to avoid extra short TCP/IP packets
uint8_t buffer[32];
size_t bufferEnd = 0;
while (buffer[bufferEnd++] = pgm_read_byte(str++))
{
if (bufferEnd == 32)
{
m_client.write(buffer, 32);
bufferEnd = 0;
}
}
// write out everything left but trailing NUL
if (bufferEnd > 1)
m_client.write(buffer, bufferEnd - 1);
}
void WebServer::printCRLF()
{
m_client.write((const uint8_t *)"\r\n", 2);
}
bool WebServer::dispatchCommand(ConnectionType requestType, char *verb,
bool tail_complete)
{
if ((verb[0] == 0) || ((verb[0] == '/') && (verb[1] == 0)))
{
m_defaultCmd(*this, requestType, verb, tail_complete);
return true;
}
// We now know that the URL contains at least one character. And,
// if the first character is a slash, there's more after it.
if (verb[0] == '/')
{
char i;
char *qm_loc;
int verb_len;
int qm_offset;
// Skip over the leading "/", because it makes the code more
// efficient and easier to understand.
verb++;
// Look for a "?" separating the filename part of the URL from the
// parameters. If it's not there, compare to the whole URL.
qm_loc = strchr(verb, '?');
verb_len = (qm_loc == NULL) ? strlen(verb) : (qm_loc - verb);
qm_offset = (qm_loc == NULL) ? 0 : 1;
for (i = 0; i < m_cmdCount; ++i)
{
if ((verb_len == strlen(m_commands[i].verb))
&& (strncmp(verb, m_commands[i].verb, verb_len) == 0))
{
// Skip over the "verb" part of the URL (and the question
// mark, if present) when passing it to the "action" routine
m_commands[i].cmd(*this, requestType,
verb + verb_len + qm_offset,
tail_complete);
return true;
}
}
}
return false;
}
// processConnection with a default buffer
void WebServer::processConnection()
{
char request[WEBDUINO_DEFAULT_REQUEST_LENGTH];
int request_len = WEBDUINO_DEFAULT_REQUEST_LENGTH;
processConnection(request, &request_len);
}
void WebServer::processConnection(char *buff, int *bufflen)
{
m_client = m_server.available();
if (m_client) {
m_readingContent = false;
buff[0] = 0;
ConnectionType requestType = INVALID;
#if WEBDUINO_SERIAL_DEBUGGING > 1
Serial.println("*** checking request ***");
#endif
getRequest(requestType, buff, bufflen);
#if WEBDUINO_SERIAL_DEBUGGING > 1
Serial.print("*** requestType = ");
Serial.print((int)requestType);
Serial.println(", request = \"");
Serial.print(buff);
Serial.println("\" ***");
#endif
processHeaders();
#if WEBDUINO_SERIAL_DEBUGGING > 1
Serial.println("*** headers complete ***");
#endif
int urlPrefixLen = strlen(m_urlPrefix);
if (strcmp(buff, "/robots.txt") == 0)
{
noRobots(requestType);
}
else if (requestType == INVALID ||
strncmp(buff, m_urlPrefix, urlPrefixLen) != 0 ||
!dispatchCommand(requestType, buff + urlPrefixLen,
(*bufflen) >= 0))
{
m_failureCmd(*this, requestType, buff, (*bufflen) >= 0);
}
#if WEBDUINO_SERIAL_DEBUGGING > 1
Serial.println("*** stopping connection ***");
#endif
m_client.stop();
}
}
void WebServer::httpFail()
{
P(failMsg) =
"HTTP/1.0 400 Bad Request" CRLF
WEBDUINO_SERVER_HEADER
"Content-Type: text/html" CRLF
CRLF
WEBDUINO_FAIL_MESSAGE;
printP(failMsg);
}
void WebServer::defaultFailCmd(WebServer &server,
WebServer::ConnectionType type,
char *url_tail,
bool tail_complete)
{
server.httpFail();
}
void WebServer::noRobots(ConnectionType type)
{
httpSuccess("text/plain");
if (type != HEAD)
{
P(allowNoneMsg) = "User-agent: *" CRLF "Disallow: /" CRLF;
printP(allowNoneMsg);
}
}
void WebServer::httpSuccess(const char *contentType,
const char *extraHeaders)
{
P(successMsg1) =
"HTTP/1.0 200 OK" CRLF
WEBDUINO_SERVER_HEADER
"Access-Control-Allow-Origin: *" CRLF
"Content-Type: ";
printP(successMsg1);
print(contentType);
printCRLF();
if (extraHeaders)
print(extraHeaders);
printCRLF();
}
void WebServer::httpSeeOther(const char *otherURL)
{
P(seeOtherMsg) =
"HTTP/1.0 303 See Other" CRLF
WEBDUINO_SERVER_HEADER
"Location: ";
printP(seeOtherMsg);
print(otherURL);
printCRLF();
printCRLF();
}
int WebServer::read()
{
if (m_client == NULL)
return -1;
if (m_pushbackDepth == 0)
{
unsigned long timeoutTime = millis() + WEBDUINO_READ_TIMEOUT_IN_MS;
while (m_client.connected())
{
// stop reading the socket early if we get to content-length
// characters in the POST. This is because some clients leave
// the socket open because they assume HTTP keep-alive.
if (m_readingContent)
{
if (m_contentLength == 0)
{
#if WEBDUINO_SERIAL_DEBUGGING > 1
Serial.println("\n*** End of content, terminating connection");
#endif
return -1;
}
--m_contentLength;
}
int ch = m_client.read();
// if we get a character, return it, otherwise continue in while
// loop, checking connection status
if (ch != -1)
{
#if WEBDUINO_SERIAL_DEBUGGING
if (ch == '\r')
Serial.print("");
else if (ch == '\n')
Serial.println("");
else
Serial.print((char)ch);
#endif
return ch;
}
else
{
unsigned long now = millis();
if (now > timeoutTime)
{
// connection timed out, destroy client, return EOF
#if WEBDUINO_SERIAL_DEBUGGING
Serial.println("*** Connection timed out");
#endif
m_client.flush();
m_client.stop();
return -1;
}
}
}
// connection lost, return EOF
#if WEBDUINO_SERIAL_DEBUGGING
Serial.println("*** Connection lost");
#endif
return -1;
}
else
return m_pushback[--m_pushbackDepth];
}
void WebServer::push(int ch)
{
// don't allow pushing EOF
if (ch == -1)
return;
m_pushback[m_pushbackDepth++] = ch;
// can't raise error here, so just replace last char over and over
if (m_pushbackDepth == SIZE(m_pushback))
m_pushbackDepth = SIZE(m_pushback) - 1;
}
void WebServer::reset()
{
m_pushbackDepth = 0;
}
bool WebServer::expect(const char *str)
{
const char *curr = str;
while (*curr != 0)
{
int ch = read();
if (ch != *curr++)
{
// push back ch and the characters we accepted
push(ch);
while (--curr != str)
push(curr[-1]);
return false;
}
}
return true;
}
bool WebServer::readInt(int &number)
{
bool negate = false;
bool gotNumber = false;
int ch;
number = 0;
// absorb whitespace
do
{
ch = read();
} while (ch == ' ' || ch == '\t');
// check for leading minus sign
if (ch == '-')
{
negate = true;
ch = read();
}
// read digits to update number, exit when we find non-digit
while (ch >= '0' && ch <= '9')
{
gotNumber = true;
number = number * 10 + ch - '0';
ch = read();
}
push(ch);
if (negate)
number = -number;
return gotNumber;
}
bool WebServer::readPOSTparam(char *name, int nameLen,
char *value, int valueLen)
{
// assume name is at current place in stream
int ch;
// clear out name and value so they'll be NUL terminated
memset(name, 0, nameLen);
memset(value, 0, valueLen);
// decrement length so we don't write into NUL terminator
--nameLen;
--valueLen;
while ((ch = read()) != -1)
{
if (ch == '+')
{
ch = ' ';
}
else if (ch == '=')
{
/* that's end of name, so switch to storing in value */
nameLen = 0;
continue;
}
else if (ch == '&')
{
/* that's end of pair, go away */
return true;
}
else if (ch == '%')
{
/* handle URL encoded characters by converting back to original form */
int ch1 = read();
int ch2 = read();
if (ch1 == -1 || ch2 == -1)
return false;
char hex[3] = { ch1, ch2, 0 };
ch = strtoul(hex, NULL, 16);
}
// check against 1 so we don't overwrite the final NUL
if (nameLen > 1)
{
*name++ = ch;
--nameLen;
}
else if (valueLen > 1)
{
*value++ = ch;
--valueLen;
}
}
// if we get here, we hit the end-of-file, so POST is over and there
// are no more parameters
return false;
}
/* Retrieve a parameter that was encoded as part of the URL, stored in
* the buffer pointed to by *tail. tail is updated to point just past
* the last character read from the buffer. */
URLPARAM_RESULT WebServer::nextURLparam(char **tail, char *name, int nameLen,
char *value, int valueLen)
{
// assume name is at current place in stream
char ch, hex[3];
URLPARAM_RESULT result = URLPARAM_OK;
char *s = *tail;
bool keep_scanning = true;
bool need_value = true;
// clear out name and value so they'll be NUL terminated
memset(name, 0, nameLen);
memset(value, 0, valueLen);
if (*s == 0)
return URLPARAM_EOS;
// Read the keyword name
while (keep_scanning)
{
ch = *s++;
switch (ch)
{
case 0:
s--; // Back up to point to terminating NUL
// Fall through to "stop the scan" code
case '&':
/* that's end of pair, go away */
keep_scanning = false;
need_value = false;
break;
case '+':
ch = ' ';
break;
case '%':
/* handle URL encoded characters by converting back
* to original form */
if ((hex[0] = *s++) == 0)
{
s--; // Back up to NUL
keep_scanning = false;
need_value = false;
}
else
{
if ((hex[1] = *s++) == 0)
{
s--; // Back up to NUL
keep_scanning = false;
need_value = false;
}
else
{
hex[2] = 0;
ch = strtoul(hex, NULL, 16);
}
}
break;
case '=':
/* that's end of name, so switch to storing in value */
keep_scanning = false;
break;
}
// check against 1 so we don't overwrite the final NUL
if (keep_scanning && (nameLen > 1))
{
*name++ = ch;
--nameLen;
}
else
result = URLPARAM_NAME_OFLO;
}
if (need_value && (*s != 0))
{
keep_scanning = true;
while (keep_scanning)
{
ch = *s++;
switch (ch)
{
case 0:
s--; // Back up to point to terminating NUL
// Fall through to "stop the scan" code
case '&':
/* that's end of pair, go away */
keep_scanning = false;
need_value = false;
break;
case '+':
ch = ' ';
break;
case '%':
/* handle URL encoded characters by converting back to original form */
if ((hex[0] = *s++) == 0)
{
s--; // Back up to NUL
keep_scanning = false;
need_value = false;
}
else
{
if ((hex[1] = *s++) == 0)
{
s--; // Back up to NUL
keep_scanning = false;
need_value = false;
}
else
{
hex[2] = 0;
ch = strtoul(hex, NULL, 16);
}
}
break;
}
// check against 1 so we don't overwrite the final NUL
if (keep_scanning && (valueLen > 1))
{
*value++ = ch;
--valueLen;
}
else
result = (result == URLPARAM_OK) ?
URLPARAM_VALUE_OFLO :
URLPARAM_BOTH_OFLO;
}
}
*tail = s;
return result;
}
// Read and parse the first line of the request header.
// The "command" (GET/HEAD/POST) is translated into a numeric value in type.
// The URL is stored in request, up to the length passed in length
// NOTE 1: length must include one byte for the terminating NUL.
// NOTE 2: request is NOT checked for NULL, nor length for a value < 1.
// Reading stops when the code encounters a space, CR, or LF. If the HTTP
// version was supplied by the client, it will still be waiting in the input
// stream when we exit.
//
// On return, length contains the amount of space left in request. If it's
// less than 0, the URL was longer than the buffer, and part of it had to
// be discarded.
void WebServer::getRequest(WebServer::ConnectionType &type,
char *request, int *length)
{
--*length; // save room for NUL
type = INVALID;
// store the GET/POST line of the request
if (expect("GET "))
type = GET;
else if (expect("HEAD "))
type = HEAD;
else if (expect("POST "))
type = POST;
// if it doesn't start with any of those, we have an unknown method
// so just eat rest of header
int ch;
while ((ch = read()) != -1)
{
// stop storing at first space or end of line
if (ch == ' ' || ch == '\n' || ch == '\r')
{
break;
}
if (*length > 0)
{
*request = ch;
++request;
--*length;
}
}
// NUL terminate
*request = 0;
}
void WebServer::processHeaders()
{
// look for two things: the Content-Length header and the double-CRLF
// that ends the headers.
while (1)
{
if (expect("Content-Length:"))
{
readInt(m_contentLength);
#if WEBDUINO_SERIAL_DEBUGGING > 1
Serial.print("\n*** got Content-Length of ");
Serial.print(m_contentLength);
Serial.print(" ***");
#endif
continue;
}
if (expect(CRLF CRLF))
{
m_readingContent = true;
return;
}
// no expect checks hit, so just absorb a character and try again
if (read() == -1)
{
return;
}
}
}
void WebServer::outputCheckboxOrRadio(const char *element, const char *name,
const char *val, const char *label,
bool selected)
{
P(cbPart1a) = "";
printP(cbPart1a);
print(element);
printP(cbPart1b);
print(name);
printP(cbPart2);
print(val);
printP(cbPart3);
if (selected)
printP(cbChecked);
printP(cbPart4);
print(label);
printP(cbPart5);
}
void WebServer::checkBox(const char *name, const char *val,
const char *label, bool selected)
{
outputCheckboxOrRadio("checkbox", name, val, label, selected);
}
void WebServer::radioButton(const char *name, const char *val,
const char *label, bool selected)
{
outputCheckboxOrRadio("radio", name, val, label, selected);
}