source: roaraudio/plugins/universal/protocol-http.c @ 5727:9e76f3c57c5f

//protocol-http.c:

/*
 *      Copyright (C) Philipp 'ph3-der-loewe' Schafft - 2011-2012
 *
 *  This file is part of roard a part of RoarAudio,
 *  a cross-platform sound system for both, home and professional use.
 *  See README for details.
 *
 *  This file is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 3
 *  as published by the Free Software Foundation.
 *
 *  RoarAudio is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this software; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 51 Franklin Street, Fifth Floor,
 *  Boston, MA 02110-1301, USA.
 *
 */

#include <roaraudio.h>
#ifdef ROAR_HAVE_LIBUSTE
#include <uste.h>
#endif

struct resource_handle;

enum ctl_cmd {
 CMD_SET_CLIENTNAME
};

enum status {
 STATUS_WAITING_FOR_HEADERS = 0,
 STATUS_END_OF_HEADER,
 STATUS_BAD_HEADER,
 STATUS_RUNNING_DATA,
 STATUS_DONE
};

struct input_source {
 int userdata_si;
 void * userdata_vp;
 ssize_t offset;
 struct roar_vio_calls * vio;
 struct roar_vio_calls vio_store;
};

struct http_client {
 enum status status;
 struct roar_buffer * input_buffer;
 char * method;
 char * proto;
 char * uri;
 char * path, * query_string;
 void * headersstore;
 struct roar_keyval * headers;
 ssize_t headerslen;
 const struct resource_handle * resource;
 struct input_source input;
 struct roar_dl_librarypara * pluginpara;
 int clientid;
};

struct resource_handle {
 const char  * uri;
 const char  * rawdata;
 const ssize_t rawlen;
 const char  * content_type;
 int (*header_send)(struct http_client * self, struct roar_buffer ** obuffer);
 int (*body_send)(struct http_client * self, struct roar_buffer ** obuffer);
};

static struct {
 enum {
  HOSTTYPE_GENERIC = 0,
  HOSTTYPE_ROARD
 } hosttype;
 union {
  struct {
   int (*clients_set_name)(int id, const char * name);
  } roard;
 } hostspec;
} __host = {.hosttype = HOSTTYPE_GENERIC};

static int header_send(struct roar_buffer ** obuffer, int status, const char * msg, const char * content_type, ssize_t len);
static void send_errorpage(struct http_client * self, struct roar_buffer ** obuffer, int error, const char * msg);

static int slow_zero_stream(struct http_client * self, struct roar_buffer ** obuffer) {
 struct roar_buffer * buffer;
 void * data;

 self->status = STATUS_RUNNING_DATA;

 if ( roar_buffer_new_data(&buffer, 1, &data) == -1 )
  return -1;

 *((char*)data) = 0;

 if ( roar_buffer_moveintoqueue(obuffer, &buffer) == -1 ) {
  roar_buffer_free(buffer);
  return -1;
 }

 return 0;
}

static const char * __res_vio_content_type_get(struct http_client * self) {
 const char * point = rindex(self->path, '.');

 if ( point == NULL )
  return NULL;

 point++;

 if ( !strcmp(point, "txt") || !strcmp(point, "text") ) {
  return "text/plain";
 } else if ( !strcmp(point, "htm") || !strcmp(point, "html") ) {
  return "text/html";
 } else if ( !strcmp(point, "css") ) {
  return "text/css";
 } else if ( !strcmp(point, "png") ) {
  return "image/png";
 } else if ( !strcmp(point, "jpg") || !strcmp(point, "jpeg") ) {
  return "image/jpeg";
 }

 return NULL;
}

#ifdef ROAR_HAVE_LIBUSTE
static uste_var_t __res_vio_handle_uste_build_headers(struct http_client * self) {
 uste_var_t root = uste_var_new_kv();
 uste_var_t var;
 ssize_t i;

 if ( root == NULL )
  return NULL;

 uste_var_set_key(root, "header");

 for (i = 0; i < self->headerslen; i++) {
  var = uste_var_new_str(self->headers[i].value == NULL ? "" : self->headers[i].value);
  if ( self->headers[i].key != NULL )
   uste_var_set_key(var, self->headers[i].key);
  uste_var_push(root, var);
  uste_var_unref(var);
 }

 return root;
}

static inline int __is_hex(char c) {
 if ( c >= '0' && c <= '9' )
  return 1;
 if ( c >= 'a' && c <= 'f' )
  return 1;
 if ( c >= 'A' && c <= 'F' )
  return 1;
 return 0;
}

static inline int __hex2num(char c) {
 if ( c >= '0' && c <= '9' )
  return c - '0';
 if ( c >= 'a' && c <= 'f' )
  return c - 'a' + 10;
 if ( c >= 'A' && c <= 'F' )
  return c - 'A' + 10;
 return 0;
}

static void __res_vio_handle_uste_uridecode(char * str) {
 const char * c = str;

 for (; *c; c++) {
  if ( *c == '%' && __is_hex(c[1]) && __is_hex(c[2]) ) {
   *str = __hex2num(c[1])*16 + __hex2num(c[2]);
   str++;
   c += 2;
  } else {
   *str = *c;
   str++;
  }
 }
 *str = *c;
}

static void __res_vio_handle_uste_keyify(char * str) {
 if ( *str == '#' )
  *str = '_';
 for (;*str; str++)
  if (*str == '.')
   *str = '_';
}

static uste_var_t __res_vio_handle_uste_build_getparams(struct http_client * self) {
 uste_var_t root = uste_var_new_kv();
 uste_var_t subroot;
 uste_var_t var;
 char * qs_buffer;
 char * cur;
 char * state;
 char * key, * value;

 if ( root == NULL )
  return NULL;

 uste_var_set_key(root, "get");
 if ( self->query_string == NULL )
  return root;

 qs_buffer = roar_mm_strdup(self->query_string);

 // do better handling here.
 if ( qs_buffer == NULL )
  return root;

 cur = roar_mm_strtok_r(qs_buffer, "&", &state);

 while (cur != NULL) {
  key = cur;
  value = strstr(cur, "=");
  if ( value != NULL ) {
   *value = 0;
   value++;
   __res_vio_handle_uste_uridecode(value);
  }
  __res_vio_handle_uste_uridecode(key);
  __res_vio_handle_uste_keyify(key);

  if ( value == NULL ) {
   var = uste_var_new_undef();
  } else {
   var = uste_var_new_str(value);
  }

  subroot = uste_var_pull(root, key);
  if ( subroot == NULL ) {
   subroot = uste_var_new_array();
   if ( subroot != NULL ) {
    uste_var_set_key(subroot, key);
    uste_var_push(root, subroot);
   }
  }

  if ( subroot != NULL ) {
   uste_var_push(subroot, var);
   uste_var_unref(subroot);
  }
  uste_var_unref(var);
  cur = roar_mm_strtok_r(NULL, "&", &state);
 }

 roar_mm_free(qs_buffer);
 return root;
}

static uste_var_t __res_vio_handle_uste_build_rootkv(struct http_client * self) {
 uste_var_t root = uste_var_new_kv();
 uste_var_t subroot, subsubroot;
 uste_var_t var;

 if ( root == NULL )
  return NULL;

#define __new_member_prefix(prefix,name) \
   if ( prefix->name != NULL ) { \
    var = uste_var_new_str(prefix->name); \
    uste_var_set_key(var, #name); \
    uste_var_push(subsubroot, var); \
    uste_var_unref(var); \
   }
#define __new_member(name) __new_member_prefix(self,name)

 subroot = uste_var_new_kv();
 if ( subroot != NULL ) {
  uste_var_set_key(subroot, "__client__");
  uste_var_push(root, subroot);

  var = uste_var_new_int(self->clientid);
  uste_var_set_key(var, "clientid");
  uste_var_push(subroot, var);
  uste_var_unref(var);

  subsubroot = uste_var_new_kv();
  if ( subsubroot != NULL ) {
   uste_var_set_key(subsubroot, "http");
   uste_var_push(subroot, subsubroot);

   __new_member(method);
   __new_member(proto);
   __new_member(uri);
   __new_member(path);
   __new_member(query_string);

   var = __res_vio_handle_uste_build_headers(self);
   uste_var_push(subsubroot, var);
   uste_var_unref(var);

   var = __res_vio_handle_uste_build_getparams(self);
   uste_var_push(subsubroot, var);
   uste_var_unref(var);

   uste_var_unref(subsubroot);
  }

  uste_var_unref(subroot);
 }

 subroot = uste_var_new_kv();
 if ( subroot != NULL ) {
  uste_var_set_key(subroot, "__host__");
  uste_var_push(root, subroot);

  subsubroot = subroot;
  __new_member_prefix(self->pluginpara, appname);
  __new_member_prefix(self->pluginpara, abiversion);

  uste_var_unref(subroot);
 }

 return root;
}

static void __res_vio_handle_uste(struct http_client * self, struct roar_buffer ** obuffer, const char * content_type) {
 struct roar_buffer * buffer = NULL;
 uste_renderer_t renderer;
 uste_parser_t parser;
 uste_var_t rootkv;
 uste_node_t root;
 int err;


 parser = uste_parser_new(self->input.vio);
 err = roar_error;
 roar_vio_close(self->input.vio);
 if ( parser == NULL ) {
  send_errorpage(self, obuffer, err, NULL);
  return;
 }

 if ( uste_parser_parse(parser) == -1 ) {
  send_errorpage(self, obuffer, roar_error, NULL);
  return;
 }

 root = uste_parser_get_rootnode(parser);
 err = roar_error;
 uste_parser_unref(parser);

 if ( root == NULL ) {
  send_errorpage(self, obuffer, err, NULL);
  return;
 }

 renderer = uste_renderer_new();
 err = roar_error;
 if ( renderer == NULL ) {
  uste_node_unref(root);
  send_errorpage(self, obuffer, err, NULL);
  return;
 }

 uste_stdfunc_register_all(renderer);

 rootkv = __res_vio_handle_uste_build_rootkv(self);
 err = roar_error;
 if ( rootkv == NULL ) {
  uste_node_unref(root);
  uste_renderer_unref(renderer);
  send_errorpage(self, obuffer, err, NULL);
  return;
 }

 uste_renderer_set_rootvar(renderer, rootkv);
 uste_var_unref(rootkv);

 buffer = uste_node_render(root, renderer);
 err = roar_error;
 uste_node_unref(root);
 uste_renderer_unref(renderer);

 if ( buffer == NULL ) {
  send_errorpage(self, obuffer, err, NULL);
  return;
 }

 header_send(obuffer, 200, NULL, content_type, -1);

 if ( buffer != NULL ) {
  if ( roar_buffer_moveintoqueue(obuffer, &buffer) == -1 ) {
   roar_buffer_free(buffer);
   return;
  }
 }

 self->status = STATUS_DONE;
}
#endif

static int __res_vio_check_uste(struct http_client * self, struct roar_buffer ** obuffer, const char * content_type) {
 const size_t len = 14;
 struct roar_buffer * buffer;
 void * data;
 ssize_t ret;

 // TODO: use content type for some basic filtering.
 (void)content_type;

 *obuffer = NULL;

 if ( roar_buffer_new_data(&buffer, len, &data) == -1 )
  return -1;

 ret = roar_vio_read(self->input.vio, data, len);

 if ( ret < 1 ) {
  roar_buffer_free(buffer);
  return 0;
 }

 *obuffer = buffer;

 if ( ret == (ssize_t)len ) {
  return !strncmp(data, "@@@TEMPLATE@@@", len);
 } else {
  if ( roar_buffer_set_len(buffer, ret) == -1 ) {
   *obuffer = NULL;
   roar_buffer_free(buffer);
   return -1;
  }
  // is this really a nice idea?
  return 0;
 }
}

static int __res_vio_header_send(struct http_client * self, struct roar_buffer ** obuffer) {
 struct roar_buffer * buffer;
 struct roar_keyval * path;
 char filename[1024];
 const char * slash = "/";
 const char * content_type = NULL;

 if ( self->pluginpara == NULL ) {
  roar_err_set(ROAR_ERROR_INVAL);
  return -1;
 }

 path = roar_keyval_lookup(self->pluginpara->argv, "webroot", self->pluginpara->argc, 1);
 if ( path == NULL ) {
  if ( roar_error == ROAR_ERROR_NOENT )
   roar_err_set(ROAR_ERROR_INVAL);
  return -1;
 }

 if ( path->value == NULL ) {
  roar_err_set(ROAR_ERROR_INVAL);
  return -1;
 }

 if ( strstr(self->path, "..") != NULL || strstr(self->path, "#") != NULL ) {
  roar_err_set(ROAR_ERROR_INVAL);
  return -1;
 }

 if ( (roar_mm_strlen(path->value) + roar_mm_strlen(self->path) + 2) > sizeof(filename) ) {
  roar_err_set(ROAR_ERROR_NAMETOOLONG);
  return -1;
 }

 if ( self->path[0] == '/' || path->value[strlen(path->value)-1] == '/' )
  slash = "";

 snprintf(filename, sizeof(filename), "%s%s%s", path->value, slash, self->path);


 self->input.vio = &(self->input.vio_store);
 if ( roar_vio_open_dstr_simple(self->input.vio, filename, ROAR_VIOF_READ|ROAR_VIOF_NONBLOCK) == -1 ) {
  return -1;
 }

 if ( roar_vio_ctl(self->input.vio, ROAR_VIO_CTL_GET_MIMETYPE, &content_type) == -1 )
  content_type = NULL;

 if ( content_type == NULL )
  content_type = __res_vio_content_type_get(self);

 if ( __res_vio_check_uste(self, &buffer, content_type) == 1 ) {
  if ( buffer != NULL )
   roar_buffer_free(buffer);
#ifdef ROAR_HAVE_LIBUSTE
  __res_vio_handle_uste(self, obuffer, content_type);
  return 0;
#else
  roar_vio_close(self->input.vio);
  send_errorpage(self, obuffer, ROAR_ERROR_NOSYS, NULL);
  return 0;
#endif
 }

 header_send(obuffer, 200, NULL, content_type, -1);

 if ( buffer != NULL ) {
  if ( roar_buffer_moveintoqueue(obuffer, &buffer) == -1 ) {
   roar_buffer_free(buffer);
   return -1;
  }
 }

 self->status = STATUS_RUNNING_DATA;
 return 0;
}

static int __res_vio_body_send(struct http_client * self, struct roar_buffer ** obuffer) {
 const size_t len = 1024;
 struct roar_buffer * buffer;
 void * data;
 ssize_t ret;

 if ( self->status == STATUS_DONE )
  return 0;

 if ( roar_buffer_new_data(&buffer, len, &data) == -1 )
  return -1;

 ret = roar_vio_read(self->input.vio, data, len);

 if ( ret == -1 && roar_error == ROAR_ERROR_AGAIN ) {
  ret = 0;
 } else if ( ret < 1 ) {
  roar_buffer_free(buffer);
  if ( roar_error != ROAR_ERROR_AGAIN ) {
   self->status = STATUS_DONE;
   roar_vio_close(self->input.vio);
  }
  return 0;
 }

 if ( roar_buffer_set_len(buffer, ret) == -1 ) {
  roar_buffer_free(buffer);
  return -1;
 }

 if ( roar_buffer_moveintoqueue(obuffer, &buffer) == -1 ) {
  roar_buffer_free(buffer);
  return -1;
 }

 return 0;
}

static const struct resource_handle _g_resources[] = {
 {
  .uri = "/test/*",
  .rawdata = "Hello world!\n",
  .rawlen  = 13,
  .content_type = NULL,
  .header_send = NULL,
  .body_send = NULL
 },
 {
  .uri = "/szs/*",
  .rawdata = NULL,
  .rawlen  = -1,
  .content_type = NULL,
  .header_send = NULL,
  .body_send = slow_zero_stream
 },
 {
  .uri = "*",
  .rawdata = NULL,
  .rawlen  = -1,
  .content_type = NULL,
  .header_send = __res_vio_header_send,
  .body_send = __res_vio_body_send
 }
};


static inline int __ret(struct http_client * self, struct roar_buffer ** obuffer) {
 ROAR_DBG("__ret(self=%p, obuffer=%p{%p}): self->status=%i", self, obuffer, *obuffer, (int)self->status);
 if ( *obuffer != NULL )
  return 0;
 if ( self->status == STATUS_DONE )
  return -1;
 return 0;
}

static int __ctl(struct http_client * self, enum ctl_cmd cmd, void * argp) {
 switch (cmd) {
  case CMD_SET_CLIENTNAME:
    if ( argp == NULL ) {
     roar_err_set(ROAR_ERROR_FAULT);
     return -1;
    }
    ROAR_DBG("__ctl(self=%p, cmd=%i, argp='%s') = ?", self, (int)cmd, (const char *)argp);
    switch (__host.hosttype) {
     case HOSTTYPE_GENERIC:
       roar_err_set(ROAR_ERROR_BADHOST);
       return -1;
      break;
     case HOSTTYPE_ROARD:
       __host.hostspec.roard.clients_set_name(self->clientid, argp);
      break;
    }
   break;
 }

 roar_err_set(ROAR_ERROR_BADRQC);
 return -1;
}

static void __init(struct roar_dl_librarypara * para) {
 // TODO add some init code here.

 if ( para == NULL )
  return;

 if ( !roar_dl_para_check_version(para, "roard <0/RoarAudio>", "1.0beta8") ) {
  __host.hosttype = HOSTTYPE_ROARD;
  __host.hostspec.roard.clients_set_name = roar_dl_getsym(ROAR_DL_HANDLE_APPLICATION, "clients_set_name", -1);

  // check if *all* function have been found:
  if ( __host.hostspec.roard.clients_set_name == NULL ) {
   __host.hosttype = HOSTTYPE_GENERIC;
  }
 }
}

// this function is a wrapper for __init() with the code which should be inlined.
static inline void _init(struct roar_dl_librarypara * para) {
 static int inited = 0;
 if (inited) return;
 __init(para);
 inited = 1;
}

static const struct resource_handle * resource_lookup_by_uri(const char * uri) {
 size_t i;

 for (i = 0; i < (sizeof(_g_resources)/sizeof(*_g_resources)); i++) {
  if ( !roar_mm_strselcmp(_g_resources[i].uri, uri) ) {
   return &(_g_resources[i]);
  }
 }

 roar_err_set(ROAR_ERROR_NOENT);
 return NULL;
}

static int resource_header_send(struct http_client * self, struct roar_buffer ** obuffer) {
 if ( self->resource->header_send != NULL )
  return self->resource->header_send(self, obuffer);

 return header_send(obuffer, 200, NULL, self->resource->content_type, self->resource->rawlen);
}

static int resource_body_send(struct http_client * self, struct roar_buffer ** obuffer) {
 struct roar_buffer * buffer;
 void * data;
 int ret;

 if ( self->resource->body_send != NULL )
  return self->resource->body_send(self, obuffer);

 if ( self->resource->rawlen == -1 ) {
  self->status = STATUS_DONE;
  roar_err_set(ROAR_ERROR_INVAL);
  return -1;
 }

 if ( roar_buffer_new_data(&buffer, self->resource->rawlen, &data) == -1 ) {
  self->status = STATUS_DONE;
  return -1;
 }

 memcpy(data, self->resource->rawdata, self->resource->rawlen);

 ret = roar_buffer_moveintoqueue(obuffer, &buffer);
 self->status = STATUS_DONE;

 return ret;
}

static int header_parse(struct http_client * self) {
 void * data;
 size_t len;
 size_t i;
 char * start, * end;
 char * start_uri;
 char * start_headers, * end_headers = NULL;
 char * tmp;
 struct roar_keyval * c;

 if ( roar_buffer_get_datalen(self->input_buffer, &data, &len) == -1 )
  return -1;

 ROAR_DBG("header_parse(self=%p): data='%*s'", self, (int)len, (const char*)data);

 if ( len < 4 )
  return 0;

 for (i = 0; i < (len - 3); i++) {
  if ( ((const char*)data)[i] == '\r' ) {
   ROAR_DBG("header_parse(self=%p): i=%i", self, (int)i);
   if ( !strncmp(data + i, "\r\n\r\n", 4) ) {
    self->status = STATUS_END_OF_HEADER;
    end_headers = data + i;
    break;
   }
  }
 }

 if ( self->status != STATUS_END_OF_HEADER ) {
  for (i = 0; i < (len - 1); i++) {
   if ( ((const char*)data)[i] == '\n' ) {
    ROAR_DBG("header_parse(self=%p): i=%i", self, (int)i);
    if ( !strncmp(data + i, "\n\n", 2) ) {
     self->status = STATUS_END_OF_HEADER;
     end_headers = data + i;
     break;
    }
   }
  }
 }

 if ( self->status != STATUS_END_OF_HEADER )
  return 0;

 *end_headers = 0;

 end = strstr(data, " ");
 if ( end == NULL ) {
  self->status = STATUS_BAD_HEADER;
  return 1;
 }

 *end = 0;
 end++;
 self->method = roar_mm_strdup(data);

 start = end;

 end = strstr(start, " ");
 if ( end == NULL ) {
  self->status = STATUS_BAD_HEADER;
  return 1;
 }

 *end = 0;
 end++;
 self->uri = roar_mm_strdup(start);
 start_uri = start;

 start = end;

 end = strstr(start, "\r");
 if ( end == NULL )
  end = strstr(start, "\n");
 if ( end == NULL ) {
  self->status = STATUS_BAD_HEADER;
  return 1;
 }

 *end = 0;
 end++;
 self->proto = roar_mm_strdup(start);

 start_headers = end;

 start = start_uri;

 end = strstr(start, "?");
 if ( end == NULL ) {
  self->path = roar_mm_strdup(start);
 } else {
  *end = 0;
  end++;
  self->path = roar_mm_strdup(start);
  self->query_string = roar_mm_strdup(end);
 }

 self->headerslen = 0;

 i = end_headers - start_headers + 1;
 self->headersstore = roar_mm_memdup(start_headers, i);
 if ( self->headersstore == NULL ) {
  self->status = STATUS_BAD_HEADER; // TODO: FIXME: not the right error, but works. ;)
  return -1;
 }

 start_headers = self->headersstore;
 end_headers   = start_headers + i;

 for (tmp = start_headers; tmp < end_headers;) {
  for (; tmp < end_headers && (*tmp == '\r' || *tmp == '\n'); tmp++);
  if ( tmp == end_headers )
   break;
  self->headerslen++;
  for (; tmp < end_headers && !(*tmp == '\r' || *tmp == '\n'); tmp++);
 }

 ROAR_DBG("header_parse(self=%p): self->headerslen=%i", self, (int)self->headerslen);

 self->headers = roar_mm_malloc(sizeof(struct roar_keyval)*(self->headerslen+1));
 if ( self->headers == NULL ) {
  self->status = STATUS_BAD_HEADER; // TODO: FIXME: not the right error, but works. ;)
  return -1;
 }
 memset(self->headers, 0, sizeof(struct roar_keyval)*(self->headerslen+1));
 c = self->headers;

 for (tmp = start_headers; tmp < end_headers;) {
  ROAR_DBG("header_parse(self=%p): tmp='%s'", self, tmp);
  for (; tmp < end_headers && (*tmp == '\r' || *tmp == '\n'); tmp++) *tmp = '\0';
  if ( tmp == end_headers )
   break;
  ROAR_DBG("header_parse(self=%p): tmp='%s'", self, tmp);
  c->key = tmp;
  ROAR_DBG("header_parse(self=%p): c->key='%s'", self, c->key);
  for (; tmp < end_headers && !(*tmp == '\r' || *tmp == '\n' || *tmp == ':'); tmp++);
  c->value = tmp;
  for (; tmp < end_headers && !(*tmp == '\r' || *tmp == '\n'); tmp++);
  c++;
 }

 c->key = NULL;
 c->value = NULL;

 for (i = 0; i < (size_t)self->headerslen; i++) {
  c = &(self->headers[i]);
  if ( c->value[0] == '\0' ) {
   c->value = NULL;
   continue;
  }

  c->value[0] = '\0';
  c->value++;

  for (; c->value[0] == ' '; c->value++);

  if ( c->value[0] == '\0' )
   c->value = NULL;
 }

 return 1;
}

static int header_send(struct roar_buffer ** obuffer, int status, const char * msg, const char * content_type, ssize_t len) {
 struct roar_buffer * buffer;
 size_t bufferlen = 1024;
 void * data;
 char buffer_len[64];

 if ( roar_buffer_new_data(&buffer, bufferlen, &data) == -1 )
  return -1;

 if ( msg == NULL ) {
  switch (status) {
   case 200: msg = "OK"; break;
   case 400: msg = "Bad Request"; break;
   case 404: msg = "File not found"; break;
   case 500: msg = "Internal server error"; break;
   default:  msg = "<<<unknown status code>>>"; break;
  }
 }

 if ( content_type == NULL )
  content_type = "text/plain";

 if ( len == (ssize_t)-1 ) {
  buffer_len[0] = 0;
 } else {
  snprintf(buffer_len, sizeof(buffer_len), "Content-Length: %lu\r\n", (long unsigned int)len);
 }

/*
Date: Sun, 29 Jul 2012 01:08:15 GMT
Cache-Control: no-cache,no-store
Content-Type: text/html; charset=%s
*/
 snprintf(data, bufferlen, "HTTP/1.0 %i %s\r\n"
                           "Server: protocol-http (libroar plugin)\r\n"
                           "Connection: close\r\n"
                           "Content-Type: %s\r\n"
                           "%s"
                           "\r\n",
                           status, msg, content_type, buffer_len
                           );

 if ( roar_buffer_set_len(buffer, roar_mm_strlen(data)) == -1 ) {
  roar_buffer_free(buffer);
  return -1;
 }

 if ( roar_buffer_moveintoqueue(obuffer, &buffer) == -1 ) {
  roar_buffer_free(buffer);
  return -1;
 }

 return 0;
}

static void send_errorpage(struct http_client * self, struct roar_buffer ** obuffer, int error, const char * msg) {
 struct roar_buffer * buffer;
 const size_t bufferlen = 1024;
 void * data;
 int httperror;

 if ( roar_err_convert(&httperror, ROAR_ERROR_TYPE_HTTP, error, ROAR_ERROR_TYPE_ROARAUDIO) == -1 )
  httperror = 500;

 if ( msg == NULL )
  msg = roar_error2str(error);

 // send header and mark as done early so we can just return in case some of the later calls fail.
 header_send(obuffer, httperror, msg, "text/html", -1);
 self->status = STATUS_DONE;

 if ( roar_buffer_new_data(&buffer, bufferlen, &data) == -1 )
  return;

 snprintf(data, bufferlen, "<html>\n"
                           " <head><title>%i - %s</title></head>\n"
                           " <body>\n"
                           "  <h1>%i - %s</h1><hr>\n"
                           " </body>\n"
                           "</html>",
                           httperror, msg, httperror, msg);

 _LIBROAR_IGNORE_RET(roar_buffer_set_len(buffer, roar_mm_strlen(data)));

 if ( roar_buffer_moveintoqueue(obuffer, &buffer) == -1 )
  roar_buffer_free(buffer);
}

static void handle_client(struct http_client * self, struct roar_buffer ** obuffer) {
 struct roar_keyval * kv;

 // meta stuff:
 // try to set client name.
 kv = roar_keyval_lookup(self->headers, "user-agent", self->headerslen, 0);
 if ( kv != NULL && kv->value != NULL ) {
  __ctl(self, CMD_SET_CLIENTNAME, kv->value);
 }

 // first try lookup including query string. if nothing is found
 // retry search with only resource path.
 self->resource = resource_lookup_by_uri(self->uri);
 if ( self->resource == NULL )
  self->resource = resource_lookup_by_uri(self->path);

 if ( self->resource == NULL ) {
  send_errorpage(self, obuffer, roar_error, NULL);
  return;
 }

 if ( resource_header_send(self, obuffer) == -1 ) {
  send_errorpage(self, obuffer, roar_error, NULL);
  return;
 }

 resource_body_send(self, obuffer);

 //send_errorpage(self, obuffer, ROAR_ERROR_CAUSALITY, NULL);
// send_errorpage(self, obuffer, roar_random_uint16() % ROAR_ERROR_BADLICENSE, NULL);
 return;
}


static int _set_proto(int client, struct roar_vio_calls * vio, struct roar_buffer ** obuffer, void ** userdata, const struct roar_keyval * protopara, ssize_t protoparalen, struct roar_dl_librarypara * pluginpara) {
 struct http_client * self = roar_mm_malloc(sizeof(struct http_client));

 (void)vio, (void)protopara, (void)protoparalen;

 if ( self == NULL )
  return -1;

 _init(pluginpara);

 memset(self, 0, sizeof(*self));
 self->status = STATUS_WAITING_FOR_HEADERS;
 self->headerslen = (ssize_t)-1;
 self->clientid = client;

 if ( pluginpara != NULL ) {
  roar_dl_para_ref(pluginpara);
  self->pluginpara = pluginpara;
 }

 *userdata = self;

 return __ret(self, obuffer);
}

static int _unset_proto(int client, struct roar_vio_calls * vio, struct roar_buffer ** obuffer, void ** userdata, const struct roar_keyval * protopara, ssize_t protoparalen, struct roar_dl_librarypara * pluginpara) {
 struct http_client * self = *userdata;

 (void)client, (void)vio, (void)obuffer, (void)protopara, (void)protoparalen, (void)pluginpara;

 if ( self->input_buffer != NULL )
  roar_buffer_free(self->input_buffer);

 if ( self->method != NULL )
  roar_mm_free(self->method);
 if ( self->proto != NULL )
  roar_mm_free(self->proto);
 if ( self->uri != NULL )
  roar_mm_free(self->uri);
 if ( self->path != NULL )
  roar_mm_free(self->path);
 if ( self->query_string != NULL )
  roar_mm_free(self->query_string);
 if ( self->headersstore != NULL )
  roar_mm_free(self->headersstore);
 if ( self->headers != NULL )
  roar_mm_free(self->headers);

 if ( self->pluginpara != NULL )
  roar_dl_para_unref(self->pluginpara);

 roar_mm_free(self);
 *userdata = NULL;

 return 0;
}

#define _INCREMENT 256
static int _handle(int client, struct roar_vio_calls * vio, struct roar_buffer ** obuffer, void ** userdata, const struct roar_keyval * protopara, ssize_t protoparalen, struct roar_dl_librarypara * pluginpara) {
 struct http_client * self = *userdata;
 void * data;
 size_t oldlen;
 ssize_t ret;

 (void)client, (void)protopara, (void)protoparalen, (void)pluginpara;

 if ( self->status != STATUS_WAITING_FOR_HEADERS )
  return __ret(self, obuffer);

 if ( self->input_buffer == NULL ) {
  if ( roar_buffer_new_data(&(self->input_buffer), _INCREMENT, &data) == -1 )
   return -1;
  oldlen = 0;
 } else {
  if ( roar_buffer_get_len(self->input_buffer, &oldlen) == -1 )
   return -1;
  if ( roar_buffer_set_len(self->input_buffer, oldlen + _INCREMENT) == -1 )
   return -1;
  if ( roar_buffer_get_data(self->input_buffer, &data) == -1 )
   return -1;
 }

 data += oldlen;

 ret = roar_vio_read(vio, data, _INCREMENT);
 if ( ret == (ssize_t)-1 ) {
  // we can safely ignore return value here as we return error anyway.
  _LIBROAR_IGNORE_RET(roar_buffer_set_len(self->input_buffer, oldlen));
  return -1;
 }

 if ( roar_buffer_set_len(self->input_buffer, oldlen + ret) == -1 ) {
  ROAR_WARN("_handle(*): Can not reset buffer length. BAD. Error was: %s", roar_errorstring);
  return -1;
 }

 header_parse(self);

 if ( self->status == STATUS_BAD_HEADER ) {
  header_send(obuffer, 400, NULL, NULL, -1);
  self->status = STATUS_DONE;
 } else if ( self->status == STATUS_END_OF_HEADER ) {
  handle_client(self, obuffer);
 }

 return __ret(self, obuffer);
}

// this is a dummy function only used to kill the client after all data has been flushed.
static int _flushed(int client, struct roar_vio_calls * vio, struct roar_buffer ** obuffer, void ** userdata, const struct roar_keyval * protopara, ssize_t protoparalen, struct roar_dl_librarypara * pluginpara) {
 struct http_client * self = *userdata;

 (void)client, (void)vio, (void)protopara, (void)protoparalen, (void)pluginpara;

 ROAR_DBG("_flushed(*) = ?");

 if ( self->status == STATUS_RUNNING_DATA )
  resource_body_send(self, obuffer);

 return __ret(self, obuffer);
}

static const struct roar_dl_proto proto = {
 .proto = ROAR_PROTO_HTTP,
 .description = "Hyper Text Transfer Protocol",
 .flags = ROAR_DL_PROTO_FLAGS_NONE,
 .set_proto = _set_proto,
 .unset_proto = _unset_proto,
 .handle = _handle,
 .flush = NULL,
 .flushed = _flushed,
 .status = NULL
};

static int __reg_proto(struct roar_dl_librarypara * para, struct roar_dl_libraryinst * lib) {
 (void)para, (void)lib;
 ROAR_DL_PLUGIN_REG_FN(ROAR_DL_PROTO_SUBTYPE, proto, ROAR_DL_PROTO_VERSION);
 return 0;
}

ROAR_DL_PLUGIN_START(protocol_http) {
 ROAR_DL_PLUGIN_META_PRODUCT_NIV("protocol-http", ROAR_VID_ROARAUDIO, ROAR_VNAME_ROARAUDIO);
 ROAR_DL_PLUGIN_META_VERSION(ROAR_VERSION_STRING);
 ROAR_DL_PLUGIN_META_LICENSE_TAG(GPLv3_0);
 ROAR_DL_PLUGIN_META_CONTACT_FLNE("Philipp", "Schafft", "ph3-der-loewe", "lion@lion.leolix.org");
 ROAR_DL_PLUGIN_META_DESC("Implementation of the HTTP Protocol");

 ROAR_DL_PLUGIN_REG(ROAR_DL_FN_PROTO, __reg_proto);
} ROAR_DL_PLUGIN_END

//ll