httpd.h

00001 /**
00002  * @file
00003  * HTTP server
00004  */
00005 
00006 /*
00007  * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
00008  * All rights reserved.
00009  *
00010  * Redistribution and use in source and binary forms, with or without modification,
00011  * are permitted provided that the following conditions are met:
00012  *
00013  * 1. Redistributions of source code must retain the above copyright notice,
00014  *    this list of conditions and the following disclaimer.
00015  * 2. Redistributions in binary form must reproduce the above copyright notice,
00016  *    this list of conditions and the following disclaimer in the documentation
00017  *    and/or other materials provided with the distribution.
00018  * 3. The name of the author may not be used to endorse or promote products
00019  *    derived from this software without specific prior written permission.
00020  *
00021  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
00022  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
00023  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
00024  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00025  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
00026  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00027  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00028  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
00029  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
00030  * OF SUCH DAMAGE.
00031  *
00032  * This file is part of the lwIP TCP/IP stack.
00033  *
00034  * Author: Adam Dunkels <adam@sics.se>
00035  *
00036  * This version of the file has been modified by Texas Instruments to offer
00037  * simple server-side-include (SSI) and Common Gateway Interface (CGI)
00038  * capability.
00039  */
00040 
00041 #ifndef LWIP_HDR_APPS_HTTPD_H
00042 #define LWIP_HDR_APPS_HTTPD_H
00043 
00044 #include "httpd_opts.h"
00045 #include "lwip/err.h"
00046 #include "lwip/pbuf.h"
00047 
00048 #ifdef __cplusplus
00049 extern "C" {
00050 #endif
00051 
00052 #if LWIP_HTTPD_CGI
00053 
00054 /*
00055  * Function pointer for a CGI script handler.
00056  *
00057  * This function is called each time the HTTPD server is asked for a file
00058  * whose name was previously registered as a CGI function using a call to
00059  * http_set_cgi_handler. The iIndex parameter provides the index of the
00060  * CGI within the ppcURLs array passed to http_set_cgi_handler. Parameters
00061  * pcParam and pcValue provide access to the parameters provided along with
00062  * the URI. iNumParams provides a count of the entries in the pcParam and
00063  * pcValue arrays. Each entry in the pcParam array contains the name of a
00064  * parameter with the corresponding entry in the pcValue array containing the
00065  * value for that parameter. Note that pcParam may contain multiple elements
00066  * with the same name if, for example, a multi-selection list control is used
00067  * in the form generating the data.
00068  *
00069  * The function should return a pointer to a character string which is the
00070  * path and filename of the response that is to be sent to the connected
00071  * browser, for example "/thanks.htm" or "/response/error.ssi".
00072  *
00073  * The maximum number of parameters that will be passed to this function via
00074  * iNumParams is defined by LWIP_HTTPD_MAX_CGI_PARAMETERS. Any parameters in the incoming
00075  * HTTP request above this number will be discarded.
00076  *
00077  * Requests intended for use by this CGI mechanism must be sent using the GET
00078  * method (which encodes all parameters within the URI rather than in a block
00079  * later in the request). Attempts to use the POST method will result in the
00080  * request being ignored.
00081  *
00082  */
00083 typedef const char *(*tCGIHandler)(int iIndex, int iNumParams, char *pcParam[],
00084                              char *pcValue[]);
00085 
00086 /*
00087  * Structure defining the base filename (URL) of a CGI and the associated
00088  * function which is to be called when that URL is requested.
00089  */
00090 typedef struct
00091 {
00092     const char *pcCGIName;
00093     tCGIHandler pfnCGIHandler;
00094 } tCGI;
00095 
00096 void http_set_cgi_handlers(const tCGI *pCGIs, int iNumHandlers);
00097 
00098 #endif /* LWIP_HTTPD_CGI */
00099 
00100 #if LWIP_HTTPD_CGI || LWIP_HTTPD_CGI_SSI
00101 
00102 #if LWIP_HTTPD_CGI_SSI
00103 /** Define this generic CGI handler in your application.
00104  * It is called once for every URI with parameters.
00105  * The parameters can be stored to 
00106  */
00107 extern void httpd_cgi_handler(const char* uri, int iNumParams, char **pcParam, char **pcValue
00108 #if defined(LWIP_HTTPD_FILE_STATE) && LWIP_HTTPD_FILE_STATE
00109                                      , void *connection_state
00110 #endif /* LWIP_HTTPD_FILE_STATE */
00111                                      );
00112 #endif /* LWIP_HTTPD_CGI_SSI */
00113 
00114 #endif /* LWIP_HTTPD_CGI || LWIP_HTTPD_CGI_SSI */
00115 
00116 #if LWIP_HTTPD_SSI
00117 
00118 /*
00119  * Function pointer for the SSI tag handler callback.
00120  *
00121  * This function will be called each time the HTTPD server detects a tag of the
00122  * form <!--#name--> in a .shtml, .ssi or .shtm file where "name" appears as
00123  * one of the tags supplied to http_set_ssi_handler in the ppcTags array.  The
00124  * returned insert string, which will be appended after the the string
00125  * "<!--#name-->" in file sent back to the client,should be written to pointer
00126  * pcInsert.  iInsertLen contains the size of the buffer pointed to by
00127  * pcInsert.  The iIndex parameter provides the zero-based index of the tag as
00128  * found in the ppcTags array and identifies the tag that is to be processed.
00129  *
00130  * The handler returns the number of characters written to pcInsert excluding
00131  * any terminating NULL or a negative number to indicate a failure (tag not
00132  * recognized, for example).
00133  *
00134  * Note that the behavior of this SSI mechanism is somewhat different from the
00135  * "normal" SSI processing as found in, for example, the Apache web server.  In
00136  * this case, the inserted text is appended following the SSI tag rather than
00137  * replacing the tag entirely.  This allows for an implementation that does not
00138  * require significant additional buffering of output data yet which will still
00139  * offer usable SSI functionality.  One downside to this approach is when
00140  * attempting to use SSI within JavaScript.  The SSI tag is structured to
00141  * resemble an HTML comment but this syntax does not constitute a comment
00142  * within JavaScript and, hence, leaving the tag in place will result in
00143  * problems in these cases.  To work around this, any SSI tag which needs to
00144  * output JavaScript code must do so in an encapsulated way, sending the whole
00145  * HTML <script>...</script> section as a single include.
00146  */
00147 typedef u16_t (*tSSIHandler)(
00148 #if LWIP_HTTPD_SSI_RAW
00149                              const char* ssi_tag_name,
00150 #else /* LWIP_HTTPD_SSI_RAW */
00151                              int iIndex,
00152 #endif /* LWIP_HTTPD_SSI_RAW */
00153                              char *pcInsert, int iInsertLen
00154 #if LWIP_HTTPD_SSI_MULTIPART
00155                              , u16_t current_tag_part, u16_t *next_tag_part
00156 #endif /* LWIP_HTTPD_SSI_MULTIPART */
00157 #if defined(LWIP_HTTPD_FILE_STATE) && LWIP_HTTPD_FILE_STATE
00158                              , void *connection_state
00159 #endif /* LWIP_HTTPD_FILE_STATE */
00160                              );
00161 
00162 /** Set the SSI handler function
00163  * (if LWIP_HTTPD_SSI_RAW==1, only the first argument is used)
00164  */
00165 void http_set_ssi_handler(tSSIHandler pfnSSIHandler,
00166                           const char **ppcTags, int iNumTags);
00167 
00168 /** For LWIP_HTTPD_SSI_RAW==1, return this to indicate the tag is unknown.
00169  * In this case, the webserver writes a warning into the page.
00170  * You can also just return 0 to write nothing for unknown tags.
00171  */
00172 #define HTTPD_SSI_TAG_UNKNOWN 0xFFFF
00173 
00174 #endif /* LWIP_HTTPD_SSI */
00175 
00176 #if LWIP_HTTPD_SUPPORT_POST
00177 
00178 /* These functions must be implemented by the application */
00179 
00180 /** Called when a POST request has been received. The application can decide
00181  * whether to accept it or not.
00182  *
00183  * @param connection Unique connection identifier, valid until httpd_post_end
00184  *        is called.
00185  * @param uri The HTTP header URI receiving the POST request.
00186  * @param http_request The raw HTTP request (the first packet, normally).
00187  * @param http_request_len Size of 'http_request'.
00188  * @param content_len Content-Length from HTTP header.
00189  * @param response_uri Filename of response file, to be filled when denying the
00190  *        request
00191  * @param response_uri_len Size of the 'response_uri' buffer.
00192  * @param post_auto_wnd Set this to 0 to let the callback code handle window
00193  *        updates by calling 'httpd_post_data_recved' (to throttle rx speed)
00194  *        default is 1 (httpd handles window updates automatically)
00195  * @return ERR_OK: Accept the POST request, data may be passed in
00196  *         another err_t: Deny the POST request, send back 'bad request'.
00197  */
00198 err_t httpd_post_begin(void *connection, const char *uri, const char *http_request,
00199                        u16_t http_request_len, int content_len, char *response_uri,
00200                        u16_t response_uri_len, u8_t *post_auto_wnd);
00201 
00202 /** Called for each pbuf of data that has been received for a POST.
00203  * ATTENTION: The application is responsible for freeing the pbufs passed in!
00204  *
00205  * @param connection Unique connection identifier.
00206  * @param p Received data.
00207  * @return ERR_OK: Data accepted.
00208  *         another err_t: Data denied, http_post_get_response_uri will be called.
00209  */
00210 err_t httpd_post_receive_data(void *connection, struct pbuf *p);
00211 
00212 /** Called when all data is received or when the connection is closed.
00213  * The application must return the filename/URI of a file to send in response
00214  * to this POST request. If the response_uri buffer is untouched, a 404
00215  * response is returned.
00216  *
00217  * @param connection Unique connection identifier.
00218  * @param response_uri Filename of response file, to be filled when denying the request
00219  * @param response_uri_len Size of the 'response_uri' buffer.
00220  */
00221 void httpd_post_finished(void *connection, char *response_uri, u16_t response_uri_len);
00222 
00223 #if LWIP_HTTPD_POST_MANUAL_WND
00224 void httpd_post_data_recved(void *connection, u16_t recved_len);
00225 #endif /* LWIP_HTTPD_POST_MANUAL_WND */
00226 
00227 #endif /* LWIP_HTTPD_SUPPORT_POST */
00228 
00229 void httpd_init(void);
00230 
00231 
00232 #ifdef __cplusplus
00233 }
00234 #endif
00235 
00236 #endif /* LWIP_HTTPD_H */