/* This file is part of libmicrohttpd Copyright (C) 2007, 2009, 2010, 2016, 2017 Daniel Pittman and Christian Grothoff This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file response.c * @brief Methods for managing response objects * @author Daniel Pittman * @author Christian Grothoff * @author Karlson2k (Evgeny Grin) */ #define MHD_NO_DEPRECATION 1 #include "mhd_options.h" #ifdef HAVE_SYS_IOCTL_H #include #endif /* HAVE_SYS_IOCTL_H */ #if defined(_WIN32) && ! defined(__CYGWIN__) #include #endif /* _WIN32 && !__CYGWIN__ */ #include "internal.h" #include "response.h" #include "mhd_limits.h" #include "mhd_sockets.h" #include "mhd_itc.h" #include "mhd_str.h" #include "connection.h" #include "memorypool.h" #include "mhd_compat.h" #if defined(MHD_W32_MUTEX_) #ifndef WIN32_LEAN_AND_MEAN #define WIN32_LEAN_AND_MEAN 1 #endif /* !WIN32_LEAN_AND_MEAN */ #include #endif /* MHD_W32_MUTEX_ */ #if defined(_WIN32) #include /* for lseek(), read() */ #endif /* _WIN32 */ /** * Add a header or footer line to the response. * * @param response response to add a header to * @param kind header or footer * @param header the header to add * @param content value to add * @return #MHD_NO on error (i.e. invalid header or content format). */ static int add_response_entry (struct MHD_Response *response, enum MHD_ValueKind kind, const char *header, const char *content) { struct MHD_HTTP_Header *hdr; if ( (NULL == response) || (NULL == header) || (NULL == content) || (0 == header[0]) || (0 == content[0]) || (NULL != strchr (header, '\t')) || (NULL != strchr (header, '\r')) || (NULL != strchr (header, '\n')) || (NULL != strchr (content, '\t')) || (NULL != strchr (content, '\r')) || (NULL != strchr (content, '\n')) ) return MHD_NO; if (NULL == (hdr = malloc (sizeof (struct MHD_HTTP_Header)))) return MHD_NO; if (NULL == (hdr->header = strdup (header))) { free (hdr); return MHD_NO; } if (NULL == (hdr->value = strdup (content))) { free (hdr->header); free (hdr); return MHD_NO; } hdr->kind = kind; hdr->next = response->first_header; response->first_header = hdr; return MHD_YES; } /** * Add a header line to the response. * * @param response response to add a header to * @param header the header to add * @param content value to add * @return #MHD_NO on error (i.e. invalid header or content format). * @ingroup response */ int MHD_add_response_header (struct MHD_Response *response, const char *header, const char *content) { return add_response_entry (response, MHD_HEADER_KIND, header, content); } /** * Add a footer line to the response. * * @param response response to remove a header from * @param footer the footer to delete * @param content value to delete * @return #MHD_NO on error (i.e. invalid footer or content format). * @ingroup response */ int MHD_add_response_footer (struct MHD_Response *response, const char *footer, const char *content) { return add_response_entry (response, MHD_FOOTER_KIND, footer, content); } /** * Delete a header (or footer) line from the response. * * @param response response to remove a header from * @param header the header to delete * @param content value to delete * @return #MHD_NO on error (no such header known) * @ingroup response */ int MHD_del_response_header (struct MHD_Response *response, const char *header, const char *content) { struct MHD_HTTP_Header *pos; struct MHD_HTTP_Header *prev; if ( (NULL == header) || (NULL == content) ) return MHD_NO; prev = NULL; pos = response->first_header; while (NULL != pos) { if ((0 == strcmp (header, pos->header)) && (0 == strcmp (content, pos->value))) { free (pos->header); free (pos->value); if (NULL == prev) response->first_header = pos->next; else prev->next = pos->next; free (pos); return MHD_YES; } prev = pos; pos = pos->next; } return MHD_NO; } /** * Get all of the headers (and footers) added to a response. * * @param response response to query * @param iterator callback to call on each header; * maybe NULL (then just count headers) * @param iterator_cls extra argument to @a iterator * @return number of entries iterated over * @ingroup response */ int MHD_get_response_headers (struct MHD_Response *response, MHD_KeyValueIterator iterator, void *iterator_cls) { int numHeaders = 0; struct MHD_HTTP_Header *pos; for (pos = response->first_header; NULL != pos; pos = pos->next) { numHeaders++; if ((NULL != iterator) && (MHD_YES != iterator (iterator_cls, pos->kind, pos->header, pos->value))) break; } return numHeaders; } /** * Get a particular header (or footer) from the response. * * @param response response to query * @param key which header to get * @return NULL if header does not exist * @ingroup response */ const char * MHD_get_response_header (struct MHD_Response *response, const char *key) { struct MHD_HTTP_Header *pos; if (NULL == key) return NULL; for (pos = response->first_header; NULL != pos; pos = pos->next) { if ( MHD_str_equal_caseless_ (pos->header, key) ) return pos->value; } return NULL; } /** * Check whether response header contains particular token. * * Token could be surrounded by spaces and tabs and delimited by comma. * Case-insensitive match used for header names and tokens. * * @param response the response to query * @param key header name * @param token the token to find * @param token_len the length of token, not including optional * terminating null-character. * @return true if token is found in specified header, * false otherwise */ bool MHD_check_response_header_token_ci (const struct MHD_Response *response, const char *key, const char *token, size_t token_len) { struct MHD_HTTP_Header *pos; if ( (NULL == key) || ('\0' == key[0]) || (NULL == token) || ('\0' == token[0]) ) return false; for (pos = response->first_header; NULL != pos; pos = pos->next) { if ( (pos->kind == MHD_HEADER_KIND) && MHD_str_equal_caseless_ (pos->header, key) && MHD_str_has_token_caseless_ (pos->value, token, token_len) ) return true; } return false; } /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the data portion of the response, #MHD_SIZE_UNKNOWN for unknown * @param block_size preferred block size for querying crc (advisory only, * MHD may still call @a crc using smaller chunks); this * is essentially the buffer size used for IO, clients * should pick a value that is appropriate for IO and * memory performance requirements * @param crc callback to use to obtain response data * @param crc_cls extra argument to @a crc * @param crfc callback to call to free @a crc_cls resources * @return NULL on error (i.e. invalid arguments, out of memory) * @ingroup response */ struct MHD_Response * MHD_create_response_from_callback (uint64_t size, size_t block_size, MHD_ContentReaderCallback crc, void *crc_cls, MHD_ContentReaderFreeCallback crfc) { struct MHD_Response *response; if ((NULL == crc) || (0 == block_size)) return NULL; if (NULL == (response = MHD_calloc_ (1, sizeof (struct MHD_Response) + block_size))) return NULL; response->fd = -1; response->data = (void *) &response[1]; response->data_buffer_size = block_size; if (! MHD_mutex_init_ (&response->mutex)) { free (response); return NULL; } response->crc = crc; response->crfc = crfc; response->crc_cls = crc_cls; response->reference_count = 1; response->total_size = size; return response; } /** * Set special flags and options for a response. * * @param response the response to modify * @param flags to set for the response * @param ... #MHD_RO_END terminated list of options * @return #MHD_YES on success, #MHD_NO on error */ int MHD_set_response_options (struct MHD_Response *response, enum MHD_ResponseFlags flags, ...) { va_list ap; int ret; enum MHD_ResponseOptions ro; ret = MHD_YES; response->flags = flags; va_start (ap, flags); while (MHD_RO_END != (ro = va_arg (ap, enum MHD_ResponseOptions))) { switch (ro) { default: ret = MHD_NO; break; } } va_end (ap); return ret; } /** * Given a file descriptor, read data from the file * to generate the response. * * @param cls pointer to the response * @param pos offset in the file to access * @param buf where to write the data * @param max number of bytes to write at most * @return number of bytes written */ static ssize_t file_reader (void *cls, uint64_t pos, char *buf, size_t max) { struct MHD_Response *response = cls; #if !defined(_WIN32) || defined(__CYGWIN__) ssize_t n; #else /* _WIN32 && !__CYGWIN__ */ const HANDLE fh = (HANDLE) _get_osfhandle (response->fd); #endif /* _WIN32 && !__CYGWIN__ */ const int64_t offset64 = (int64_t)(pos + response->fd_off); if (offset64 < 0) return MHD_CONTENT_READER_END_WITH_ERROR; /* seek to required position is not possible */ #if !defined(_WIN32) || defined(__CYGWIN__) if (max > SSIZE_MAX) max = SSIZE_MAX; /* Clamp to maximum return value. */ #if defined(HAVE_PREAD64) n = pread64(response->fd, buf, max, offset64); #elif defined(HAVE_PREAD) if ( (sizeof(off_t) < sizeof (uint64_t)) && (offset64 > (uint64_t)INT32_MAX) ) return MHD_CONTENT_READER_END_WITH_ERROR; /* Read at required position is not possible. */ n = pread(response->fd, buf, max, (off_t) offset64); #else /* ! HAVE_PREAD */ #if defined(HAVE_LSEEK64) if (lseek64 (response->fd, offset64, SEEK_SET) != offset64) return MHD_CONTENT_READER_END_WITH_ERROR; /* can't seek to required position */ #else /* ! HAVE_LSEEK64 */ if ( (sizeof(off_t) < sizeof (uint64_t)) && (offset64 > (uint64_t)INT32_MAX) ) return MHD_CONTENT_READER_END_WITH_ERROR; /* seek to required position is not possible */ if (lseek (response->fd, (off_t) offset64, SEEK_SET) != (off_t) offset64) return MHD_CONTENT_READER_END_WITH_ERROR; /* can't seek to required position */ #endif /* ! HAVE_LSEEK64 */ n = read (response->fd, buf, max); #endif /* ! HAVE_PREAD */ if (0 == n) return MHD_CONTENT_READER_END_OF_STREAM; if (n < 0) return MHD_CONTENT_READER_END_WITH_ERROR; return n; #else /* _WIN32 && !__CYGWIN__ */ if (INVALID_HANDLE_VALUE == fh) return MHD_CONTENT_READER_END_WITH_ERROR; /* Value of 'response->fd' is not valid. */ else { OVERLAPPED f_ol = {0, 0, {{0, 0}}, 0}; /* Initialize to zero. */ ULARGE_INTEGER pos_uli; DWORD toRead = (max > INT32_MAX) ? INT32_MAX : (DWORD) max; DWORD resRead; pos_uli.QuadPart = (uint64_t) offset64; /* Simple transformation 64bit -> 2x32bit. */ f_ol.Offset = pos_uli.LowPart; f_ol.OffsetHigh = pos_uli.HighPart; if (! ReadFile(fh, (void*)buf, toRead, &resRead, &f_ol)) return MHD_CONTENT_READER_END_WITH_ERROR; /* Read error. */ if (0 == resRead) return MHD_CONTENT_READER_END_OF_STREAM; return (ssize_t) resRead; } #endif /* _WIN32 && !__CYGWIN__ */ } /** * Destroy file reader context. Closes the file * descriptor. * * @param cls pointer to file descriptor */ static void free_callback (void *cls) { struct MHD_Response *response = cls; (void) close (response->fd); response->fd = -1; } #undef MHD_create_response_from_fd_at_offset /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the data portion of the response * @param fd file descriptor referring to a file on disk with the * data; will be closed when response is destroyed; * fd should be in 'blocking' mode * @param offset offset to start reading from in the file; * Be careful! `off_t` may have been compiled to be a * 64-bit variable for MHD, in which case your application * also has to be compiled using the same options! Read * the MHD manual for more details. * @return NULL on error (i.e. invalid arguments, out of memory) * @ingroup response */ struct MHD_Response * MHD_create_response_from_fd_at_offset (size_t size, int fd, off_t offset) { return MHD_create_response_from_fd_at_offset64 (size, fd, offset); } /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the data portion of the response; * sizes larger than 2 GiB may be not supported by OS or * MHD build; see ::MHD_FEATURE_LARGE_FILE * @param fd file descriptor referring to a file on disk with the * data; will be closed when response is destroyed; * fd should be in 'blocking' mode * @param offset offset to start reading from in the file; * reading file beyond 2 GiB may be not supported by OS or * MHD build; see ::MHD_FEATURE_LARGE_FILE * @return NULL on error (i.e. invalid arguments, out of memory) * @ingroup response */ _MHD_EXTERN struct MHD_Response * MHD_create_response_from_fd_at_offset64 (uint64_t size, int fd, uint64_t offset) { struct MHD_Response *response; #if !defined(HAVE___LSEEKI64) && !defined(HAVE_LSEEK64) if ( (sizeof(uint64_t) > sizeof(off_t)) && ( (size > (uint64_t)INT32_MAX) || (offset > (uint64_t)INT32_MAX) || ((size + offset) >= (uint64_t)INT32_MAX) ) ) return NULL; #endif if ( ((int64_t)size < 0) || ((int64_t)offset < 0) || ((int64_t)(size + offset) < 0) ) return NULL; response = MHD_create_response_from_callback (size, 4 * 1024, &file_reader, NULL, &free_callback); if (NULL == response) return NULL; response->fd = fd; response->fd_off = offset; response->crc_cls = response; return response; } /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the data portion of the response * @param fd file descriptor referring to a file on disk with the data * @return NULL on error (i.e. invalid arguments, out of memory) * @ingroup response */ struct MHD_Response * MHD_create_response_from_fd (size_t size, int fd) { return MHD_create_response_from_fd_at_offset64 (size, fd, 0); } /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the data portion of the response; * sizes larger than 2 GiB may be not supported by OS or * MHD build; see ::MHD_FEATURE_LARGE_FILE * @param fd file descriptor referring to a file on disk with the * data; will be closed when response is destroyed; * fd should be in 'blocking' mode * @return NULL on error (i.e. invalid arguments, out of memory) * @ingroup response */ _MHD_EXTERN struct MHD_Response * MHD_create_response_from_fd64 (uint64_t size, int fd) { return MHD_create_response_from_fd_at_offset64 (size, fd, 0); } /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the @a data portion of the response * @param data the data itself * @param must_free libmicrohttpd should free data when done * @param must_copy libmicrohttpd must make a copy of @a data * right away, the data maybe released anytime after * this call returns * @return NULL on error (i.e. invalid arguments, out of memory) * @deprecated use #MHD_create_response_from_buffer instead * @ingroup response */ struct MHD_Response * MHD_create_response_from_data (size_t size, void *data, int must_free, int must_copy) { struct MHD_Response *response; void *tmp; if ((NULL == data) && (size > 0)) return NULL; if (NULL == (response = MHD_calloc_ (1, sizeof (struct MHD_Response)))) return NULL; response->fd = -1; if (! MHD_mutex_init_ (&response->mutex)) { free (response); return NULL; } if ((must_copy) && (size > 0)) { if (NULL == (tmp = malloc (size))) { MHD_mutex_destroy_chk_ (&response->mutex); free (response); return NULL; } memcpy (tmp, data, size); must_free = MHD_YES; data = tmp; } if (must_free) { response->crfc = &free; response->crc_cls = data; } response->reference_count = 1; response->total_size = size; response->data = data; response->data_size = size; return response; } /** * Create a response object. The response object can be extended with * header information and then be used any number of times. * * @param size size of the data portion of the response * @param buffer size bytes containing the response's data portion * @param mode flags for buffer management * @return NULL on error (i.e. invalid arguments, out of memory) * @ingroup response */ struct MHD_Response * MHD_create_response_from_buffer (size_t size, void *buffer, enum MHD_ResponseMemoryMode mode) { return MHD_create_response_from_data (size, buffer, mode == MHD_RESPMEM_MUST_FREE, mode == MHD_RESPMEM_MUST_COPY); } #ifdef UPGRADE_SUPPORT /** * This connection-specific callback is provided by MHD to * applications (unusual) during the #MHD_UpgradeHandler. * It allows applications to perform 'special' actions on * the underlying socket from the upgrade. * * @param urh the handle identifying the connection to perform * the upgrade @a action on. * @param action which action should be performed * @param ... arguments to the action (depends on the action) * @return #MHD_NO on error, #MHD_YES on success */ _MHD_EXTERN int MHD_upgrade_action (struct MHD_UpgradeResponseHandle *urh, enum MHD_UpgradeAction action, ...) { struct MHD_Connection *connection; struct MHD_Daemon *daemon; if (NULL == urh) return MHD_NO; connection = urh->connection; /* Precaution checks on external data. */ if (NULL == connection) return MHD_NO; daemon = connection->daemon; if (NULL == daemon) return MHD_NO; switch (action) { case MHD_UPGRADE_ACTION_CLOSE: if (urh->was_closed) return MHD_NO; /* Already closed. */ /* transition to special 'closed' state for start of cleanup */ #ifdef HTTPS_SUPPORT if (0 != (daemon->options & MHD_USE_TLS) ) { /* signal that app is done by shutdown() of 'app' socket */ /* Application will not use anyway this socket after this command. */ shutdown (urh->app.socket, SHUT_RDWR); } #endif /* HTTPS_SUPPORT */ mhd_assert (MHD_CONNECTION_UPGRADE == connection->state); urh->was_closed = true; /* As soon as connection will be marked with BOTH * 'urh->was_closed' AND 'urh->clean_ready', it will * be moved to cleanup list by MHD_resume_connection(). */ MHD_resume_connection (connection); return MHD_YES; default: /* we don't understand this one */ return MHD_NO; } } /** * We are done sending the header of a given response to the client. * Now it is time to perform the upgrade and hand over the connection * to the application. * @remark To be called only from thread that process connection's * recv(), send() and response. Must be called right after sending * response headers. * * @param response the response that was created for an upgrade * @param connection the specific connection we are upgrading * @return #MHD_YES on success, #MHD_NO on failure (will cause * connection to be closed) */ int MHD_response_execute_upgrade_ (struct MHD_Response *response, struct MHD_Connection *connection) { struct MHD_Daemon *daemon = connection->daemon; struct MHD_UpgradeResponseHandle *urh; size_t rbo; if (0 == (daemon->options & MHD_ALLOW_UPGRADE)) return MHD_NO; if (NULL == MHD_get_response_header (response, MHD_HTTP_HEADER_UPGRADE)) { #ifdef HAVE_MESSAGES MHD_DLOG (daemon, _("Invalid response for upgrade: application failed to set the 'Upgrade' header!\n")); #endif return MHD_NO; } urh = MHD_calloc_ (1, sizeof (struct MHD_UpgradeResponseHandle)); if (NULL == urh) return MHD_NO; urh->connection = connection; rbo = connection->read_buffer_offset; connection->read_buffer_offset = 0; #ifdef HTTPS_SUPPORT if (0 != (daemon->options & MHD_USE_TLS) ) { struct MemoryPool *pool; size_t avail; char *buf; MHD_socket sv[2]; #if defined(MHD_socket_nosignal_) || !defined(MHD_socket_pair_nblk_) int res1; int res2; #endif /* MHD_socket_nosignal_ || !MHD_socket_pair_nblk_ */ #ifdef MHD_socket_pair_nblk_ if (! MHD_socket_pair_nblk_ (sv)) { free (urh); return MHD_NO; } #else /* !MHD_socket_pair_nblk_ */ if (! MHD_socket_pair_ (sv)) { free (urh); return MHD_NO; } res1 = MHD_socket_nonblocking_(sv[0]); res2 = MHD_socket_nonblocking_(sv[1]); if ( (! res1) || (! res2) ) { #ifdef HAVE_MESSAGES MHD_DLOG (daemon, _("Failed to make loopback sockets non-blocking.\n")); #endif if (! res2) { /* Socketpair cannot be used. */ MHD_socket_close_chk_ (sv[0]); MHD_socket_close_chk_ (sv[1]); free (urh); return MHD_NO; } } #endif /* !MHD_socket_pair_nblk_ */ #ifdef MHD_socket_nosignal_ res1 = MHD_socket_nosignal_(sv[0]); res2 = MHD_socket_nosignal_(sv[1]); if ( (! res1) || (! res2) ) { #ifdef HAVE_MESSAGES MHD_DLOG (daemon, _("Failed to set SO_NOSIGPIPE on loopback sockets.\n")); #endif #ifndef MSG_NOSIGNAL if (!res2) { /* Socketpair cannot be used. */ MHD_socket_close_chk_ (sv[0]); MHD_socket_close_chk_ (sv[1]); free (urh); return MHD_NO; } #endif /* ! MSG_NOSIGNAL */ } #endif /* MHD_socket_nosignal_ */ if ( (! MHD_SCKT_FD_FITS_FDSET_ (sv[1], NULL)) && (0 == (daemon->options & (MHD_USE_POLL | MHD_USE_EPOLL))) ) { #ifdef HAVE_MESSAGES MHD_DLOG (daemon, _("Socketpair descriptor larger than FD_SETSIZE: %d > %d\n"), (int) sv[1], (int) FD_SETSIZE); #endif MHD_socket_close_chk_ (sv[0]); MHD_socket_close_chk_ (sv[1]); free (urh); return MHD_NO; } urh->app.socket = sv[0]; urh->app.urh = urh; urh->app.celi = MHD_EPOLL_STATE_UNREADY; urh->mhd.socket = sv[1]; urh->mhd.urh = urh; urh->mhd.celi = MHD_EPOLL_STATE_UNREADY; pool = connection->pool; avail = MHD_pool_get_free (pool); if (avail < RESERVE_EBUF_SIZE) { /* connection's pool is totally at the limit, use our 'emergency' buffer of #RESERVE_EBUF_SIZE bytes. */ avail = RESERVE_EBUF_SIZE; buf = urh->e_buf; } else { /* Normal case: grab all remaining memory from the connection's pool for the IO buffers; the connection certainly won't need it anymore as we've upgraded to another protocol. */ buf = MHD_pool_allocate (pool, avail, MHD_NO); } /* use half the buffer for inbound, half for outbound */ urh->in_buffer_size = avail / 2; urh->out_buffer_size = avail - urh->in_buffer_size; urh->in_buffer = buf; urh->out_buffer = &buf[urh->in_buffer_size]; #ifdef EPOLL_SUPPORT /* Launch IO processing by the event loop */ if (0 != (daemon->options & MHD_USE_EPOLL)) { /* We're running with epoll(), need to add the sockets to the event set of the daemon's `epoll_upgrade_fd` */ struct epoll_event event; mhd_assert (-1 != daemon->epoll_upgrade_fd); /* First, add network socket */ event.events = EPOLLIN | EPOLLOUT | EPOLLPRI | EPOLLET; event.data.ptr = &urh->app; if (0 != epoll_ctl (daemon->epoll_upgrade_fd, EPOLL_CTL_ADD, connection->socket_fd, &event)) { #ifdef HAVE_MESSAGES MHD_DLOG (daemon, _("Call to epoll_ctl failed: %s\n"), MHD_socket_last_strerr_ ()); #endif MHD_socket_close_chk_ (sv[0]); MHD_socket_close_chk_ (sv[1]); free (urh); return MHD_NO; } /* Second, add our end of the UNIX socketpair() */ event.events = EPOLLIN | EPOLLOUT | EPOLLPRI | EPOLLET; event.data.ptr = &urh->mhd; if (0 != epoll_ctl (daemon->epoll_upgrade_fd, EPOLL_CTL_ADD, urh->mhd.socket, &event)) { event.events = EPOLLIN | EPOLLOUT | EPOLLPRI; event.data.ptr = &urh->app; if (0 != epoll_ctl (daemon->epoll_upgrade_fd, EPOLL_CTL_DEL, connection->socket_fd, &event)) MHD_PANIC (_("Error cleaning up while handling epoll error")); #ifdef HAVE_MESSAGES MHD_DLOG (daemon, _("Call to epoll_ctl failed: %s\n"), MHD_socket_last_strerr_ ()); #endif MHD_socket_close_chk_ (sv[0]); MHD_socket_close_chk_ (sv[1]); free (urh); return MHD_NO; } EDLL_insert (daemon->eready_urh_head, daemon->eready_urh_tail, urh); urh->in_eready_list = true; } #endif /* EPOLL_SUPPORT */ if (0 == (daemon->options & MHD_USE_THREAD_PER_CONNECTION) ) { /* This takes care of further processing for most event loops: simply add to DLL for bi-direcitonal processing */ DLL_insert (daemon->urh_head, daemon->urh_tail, urh); } /* In thread-per-connection mode, thread will switch to forwarding once * connection.urh is not NULL and connection.state == MHD_CONNECTION_UPGRADE. */ } else { urh->app.socket = MHD_INVALID_SOCKET; urh->mhd.socket = MHD_INVALID_SOCKET; /* Non-TLS connection do not hold any additional resources. */ urh->clean_ready = true; } #else /* ! HTTPS_SUPPORT */ urh->clean_ready = true; #endif /* ! HTTPS_SUPPORT */ connection->urh = urh; /* As far as MHD's event loops are concerned, this connection is suspended; it will be resumed once application is done by the #MHD_upgrade_action() function */ internal_suspend_connection_ (connection); /* hand over socket to application */ response->upgrade_handler (response->upgrade_handler_cls, connection, connection->client_context, connection->read_buffer, rbo, #ifdef HTTPS_SUPPORT (0 == (daemon->options & MHD_USE_TLS) ) ? connection->socket_fd : urh->app.socket, #else /* ! HTTPS_SUPPORT */ connection->socket_fd, #endif /* ! HTTPS_SUPPORT */ urh); return MHD_YES; } /** * Create a response object that can be used for 101 UPGRADE * responses, for example to implement WebSockets. After sending the * response, control over the data stream is given to the callback (which * can then, for example, start some bi-directional communication). * If the response is queued for multiple connections, the callback * will be called for each connection. The callback * will ONLY be called after the response header was successfully passed * to the OS; if there are communication errors before, the usual MHD * connection error handling code will be performed. * * Setting the correct HTTP code (i.e. MHD_HTTP_SWITCHING_PROTOCOLS) * and setting correct HTTP headers for the upgrade must be done * manually (this way, it is possible to implement most existing * WebSocket versions using this API; in fact, this API might be useful * for any protocol switch, not just WebSockets). Note that * draft-ietf-hybi-thewebsocketprotocol-00 cannot be implemented this * way as the header "HTTP/1.1 101 WebSocket Protocol Handshake" * cannot be generated; instead, MHD will always produce "HTTP/1.1 101 * Switching Protocols" (if the response code 101 is used). * * As usual, the response object can be extended with header * information and then be used any number of times (as long as the * header information is not connection-specific). * * @param upgrade_handler function to call with the 'upgraded' socket * @param upgrade_handler_cls closure for @a upgrade_handler * @return NULL on error (i.e. invalid arguments, out of memory) */ _MHD_EXTERN struct MHD_Response * MHD_create_response_for_upgrade (MHD_UpgradeHandler upgrade_handler, void *upgrade_handler_cls) { struct MHD_Response *response; if (NULL == upgrade_handler) return NULL; /* invalid request */ response = MHD_calloc_ (1, sizeof (struct MHD_Response)); if (NULL == response) return NULL; if (! MHD_mutex_init_ (&response->mutex)) { free (response); return NULL; } response->upgrade_handler = upgrade_handler; response->upgrade_handler_cls = upgrade_handler_cls; response->total_size = MHD_SIZE_UNKNOWN; response->reference_count = 1; if (MHD_NO == MHD_add_response_header (response, MHD_HTTP_HEADER_CONNECTION, "Upgrade")) { MHD_destroy_response (response); return NULL; } return response; } #endif /* UPGRADE_SUPPORT */ /** * Destroy a response object and associated resources. Note that * libmicrohttpd may keep some of the resources around if the response * is still in the queue for some clients, so the memory may not * necessarily be freed immediately. * * @param response response to destroy * @ingroup response */ void MHD_destroy_response (struct MHD_Response *response) { struct MHD_HTTP_Header *pos; if (NULL == response) return; MHD_mutex_lock_chk_ (&response->mutex); if (0 != --(response->reference_count)) { MHD_mutex_unlock_chk_ (&response->mutex); return; } MHD_mutex_unlock_chk_ (&response->mutex); MHD_mutex_destroy_chk_ (&response->mutex); if (NULL != response->crfc) response->crfc (response->crc_cls); while (NULL != response->first_header) { pos = response->first_header; response->first_header = pos->next; free (pos->header); free (pos->value); free (pos); } free (response); } /** * Increments the reference counter for the @a response. * * @param response object to modify */ void MHD_increment_response_rc (struct MHD_Response *response) { MHD_mutex_lock_chk_ (&response->mutex); (response->reference_count)++; MHD_mutex_unlock_chk_ (&response->mutex); } /* end of response.c */