include/netutils/httpd.h

/****************************************************************************
 * apps/include/netutils/httpd.h
 *
 * SPDX-License-Identifier: BSD-3-Clause
 * SPDX-FileCopyrightText: 2007, 2009-2011, 2014, 2018 Gregory Nutt
 * SPDX-FileCopyrightText: 2001-2005, Adam Dunkels.
 * SPDX-FileContributor: Gregory Nutt <gnutt@nuttx.org>
 * SPDX-FileContributor: Adam Dunkels <adam@sics.se>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote
 *    products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

#ifndef __APPS_INCLUDE_NETUTILS_HTTPD_H
#define __APPS_INCLUDE_NETUTILS_HTTPD_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/net/tcp.h>

#include <stdint.h>
#include <stdbool.h>
#include <limits.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/* As threads are created to handle each request, a stack must be allocated
 * for the thread.  Use a default if the user provided no stacksize.
 */

#ifndef CONFIG_NETUTILS_HTTPDSTACKSIZE
#  define CONFIG_NETUTILS_HTTPDSTACKSIZE 4096
#endif

/* For efficiency reasons, the size of the IO buffer should be a multiple
 * of the TCP MSS value.  Also, the current design requires that the IO
 * buffer be sufficiently large to contain the entire GET request.
 *
 * In the case where there are multiple network devices with different
 * link layer protocols, each network device may support a different TCP
 * MSS value.  Here we arbitrarily select the minimum MSS for that case.
 */

#ifndef MIN_TCP_MSS
#  error "You need to enable TCP/IP (i.e. CONFIG_NET_TCP) to use HTTPD"
#endif

#define HTTPD_IOBUFFER_SIZE (3*MIN_TCP_MSS)

/* This is the maximum size of a file path */

#ifndef CONFIG_NETUTILS_HTTPD_MAXPATH
#  define CONFIG_NETUTILS_HTTPD_MAXPATH PATH_MAX
#endif

#define HTTPD_MAX_FILENAME CONFIG_NETUTILS_HTTPD_MAXPATH

/* Other tunable values.  If you need to change these values, please create
 * new configurations in apps/netutils/webserver/Kconfig
 */

#define HTTPD_MAX_CONTENTLEN  32
#define HTTPD_MAX_HEADERLEN   220
#define HTTPD_MAX_CHUNKEDLEN  16

/****************************************************************************
 * Public types
 ****************************************************************************/

struct httpd_fs_file
{
  FAR char *data;
  int len;
#if defined(CONFIG_NETUTILS_HTTPD_MMAP) || \
    defined(CONFIG_NETUTILS_HTTPD_SENDFILE)
  int fd;
#endif
#ifdef CONFIG_NETUTILS_HTTPD_SENDFILE
  char path[PATH_MAX];
#endif
};

struct httpd_state
{
  char ht_buffer[HTTPD_IOBUFFER_SIZE];  /* recv() buffer */
  char ht_filename[HTTPD_MAX_FILENAME]; /* filename from GET command */
#ifndef CONFIG_NETUTILS_HTTPD_KEEPALIVE_DISABLE
  bool ht_keepalive;                    /* Connection: keep-alive */
#endif
#if defined(CONFIG_NETUTILS_HTTPD_ENABLE_CHUNKED_ENCODING)
  bool ht_chunked;                      /* Server uses chunked encoding for tx */
#endif
  struct httpd_fs_file ht_file;         /* Fake file data to send */
  int ht_sockfd;                        /* The socket descriptor from accept() */
  FAR char *ht_scriptptr;
  uint16_t ht_scriptlen;
  uint16_t ht_sndlen;
};

struct httpd_fsdata_file
{
  const struct httpd_fsdata_file *next;
  FAR const uint8_t *name;
  FAR const uint8_t *data;
  int len;
#ifdef CONFIG_NETUTILS_HTTPDFSSTATS
  uint16_t count;
#endif
};

struct httpd_fsdata_file_noconst
{
  FAR struct httpd_fsdata_file *next;
  FAR char *name;
  FAR char *data;
  int len;
#ifdef CONFIG_NETUTILS_HTTPDFSSTATS
  uint16_t count;
#endif
};

typedef void CODE (*httpd_cgifunction)(FAR struct httpd_state *, FAR char *);

struct httpd_cgi_call
{
  FAR struct httpd_cgi_call *next;
  FAR const char *name;
  httpd_cgifunction function;
};

/* HTTPD CGI function declaration
 *
 * Description:
 *   This macro is used for declaring a HTTPD CGI function. This function is
 *   then added to the list of HTTPD CGI functions with the
 *   httpd_cgi_register() function.

 * Input Parameters:
 *
 *   name     The C variable name of the function
 *   str      The string name of the function, used in the script file
 *   function A pointer to the function that implements it
 */

#define HTTPD_CGI_CALL(name, str, function) \
static void function(struct httpd_state *, char *); \
static struct httpd_cgi_call name = {NULL, str, function}

/****************************************************************************
 * Public Data
 ****************************************************************************/

#ifdef __cplusplus
#  define EXTERN extern "C"
extern "C"
{
#else
#  define EXTERN extern
#endif

EXTERN const struct httpd_fsdata_file g_httpdfs_root[];
EXTERN const int g_httpd_numfiles;

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

/****************************************************************************
 * Name: httpd_init
 *
 * Description:
 *   This function initializes the web server and should be called at system
 *   boot-up.
 *
 ****************************************************************************/

void httpd_init(void);

/****************************************************************************
 * Name: httpd_listen
 *
 * Description:
 *   This is the main processing thread for the webserver.  It never returns
 *   unless an error occurs
 *
 ****************************************************************************/

int httpd_listen(void);

/****************************************************************************
 * Name: httpd_cgi_register
 *
 * Description:
 *   Register a CGI handler
 *
 ****************************************************************************/

void httpd_cgi_register(FAR struct httpd_cgi_call *cgi_call);

/****************************************************************************
 * Name: httpd_send_datachunk
 *
 * Description:
 *   Sends a chunk of HTML data using either chunked or non-chunked encoding.
 *
 * Input Parameters:
 *   sockfd   Socket to which to send the data.
 *   data     Data to send
 *   len      Length of data to send
 *   chunked  If True, sends an HTTP Chunked-Encoding prolog before the data
 *            block, and a HTTP Chunked-Encoding epilog ("\r\n") after the
 *            data block. If False, just sends the data.
 *
 * Returned Value:
 *   On success, returns >=0. On failure, returns a negative number
 *   indicating the failure code.
 *
 ****************************************************************************/

int httpd_send_datachunk(int sockfd, FAR void *data, int len, bool chunked);

/****************************************************************************
 * Name: httpd_send_headers
 *
 * Description:
 *   Sends HTTP headers
 *
 * Input Parameters:
 *   pstate   The httpd state
 *   status   Numeric HTTP status code
 *   len      Length of data to be sent in subsequent send
 *
 * Returned Value:
 *   On success, returns >=0. On failure, returns a negative number
 *   indicating the failure code.
 *
 ****************************************************************************/

int httpd_send_headers(FAR struct httpd_state *pstate, int status, int len);

#ifdef CONFIG_NETUTILS_HTTPDFSSTATS
uint16_t httpd_fs_count(FAR char *name);
#endif

#ifdef CONFIG_NETUTILS_HTTPD_DIRLIST
bool httpd_is_file(FAR const char *filename);
ssize_t httpd_dirlist(int outfd, FAR struct httpd_fs_file *file);
#endif

#undef EXTERN
#ifdef __cplusplus
}
#endif

#endif /* __APPS_INCLUDE_NETUTILS_HTTPD_H */