diff options
Diffstat (limited to 'libssh/poll.c')
-rw-r--r-- | libssh/poll.c | 692 |
1 files changed, 0 insertions, 692 deletions
diff --git a/libssh/poll.c b/libssh/poll.c deleted file mode 100644 index 7942ea0..0000000 --- a/libssh/poll.c +++ /dev/null @@ -1,692 +0,0 @@ -/* - * poll.c - poll wrapper - * - * This file is part of the SSH Library - * - * Copyright (c) 2009-2010 by Andreas Schneider <mail@cynapses.org> - * Copyright (c) 2003-2009 by Aris Adamantiadis - * Copyright (c) 2009 Aleksandar Kanchev - * - * The SSH 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. - * - * The SSH 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 the SSH Library; see the file COPYING. If not, write to - * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, - * MA 02111-1307, USA. - * - * vim: ts=2 sw=2 et cindent - */ - -#include "config.h" - -#include <errno.h> - -#include "libssh/priv.h" -#include "libssh/libssh.h" -#include "libssh/poll.h" -#include "libssh/socket.h" - -#ifndef SSH_POLL_CTX_CHUNK -#define SSH_POLL_CTX_CHUNK 5 -#endif - -/** - * @defgroup libssh_poll The SSH poll functions. - * @ingroup libssh - * - * Add a generic way to handle sockets asynchronously. - * - * It's based on poll objects, each of which store a socket, it's events and a - * callback, which gets called whenever an event is set. The poll objects are - * attached to a poll context, which should be allocated on per thread basis. - * - * Polling the poll context will poll all the attached poll objects and call - * their callbacks (handlers) if any of the socket events are set. This should - * be done within the main loop of an application. - * - * @{ - */ - -/** global poll context used for blocking operations */ -static ssh_poll_ctx global_poll_ctx; - -struct ssh_poll_handle_struct { - ssh_poll_ctx ctx; - union { - socket_t fd; - size_t idx; - } x; - short events; - ssh_poll_callback cb; - void *cb_data; -}; - -struct ssh_poll_ctx_struct { - ssh_poll_handle *pollptrs; - ssh_pollfd_t *pollfds; - size_t polls_allocated; - size_t polls_used; - size_t chunk_size; -}; - -#ifdef HAVE_POLL -#include <poll.h> - -void ssh_poll_init(void) { - return; -} - -void ssh_poll_cleanup(void) { - return; -} - -int ssh_poll(ssh_pollfd_t *fds, nfds_t nfds, int timeout) { - return poll((struct pollfd *) fds, nfds, timeout); -} - -#else /* HAVE_POLL */ - -typedef int (*poll_fn)(ssh_pollfd_t *, nfds_t, int); -static poll_fn ssh_poll_emu; - -#include <sys/types.h> - -#ifdef _WIN32 -#ifndef STRICT -#define STRICT -#endif /* STRICT */ - -#include <time.h> -#include <windows.h> -#include <winsock2.h> - -#if (_WIN32_WINNT < 0x0600) -typedef struct ssh_pollfd_struct WSAPOLLFD; -#endif - -typedef int (WSAAPI* WSAPoll_FunctionType)(WSAPOLLFD fdarray[], - ULONG nfds, - INT timeout -); - -static WSAPoll_FunctionType wsa_poll; - -int win_poll(ssh_pollfd_t *fds, nfds_t nfds, int timeout) { - if (wsa_poll) { - return (wsa_poll)(fds, nfds, timeout); - } - - return SOCKET_ERROR; -} - -#define WS2_LIBRARY "ws2_32.dll" -static HINSTANCE hlib; - -#else /* _WIN32 */ -#include <sys/select.h> -#include <sys/socket.h> -#include <unistd.h> -#include <sys/time.h> -#endif /* _WIN32 */ - - -/* - * This is a poll(2)-emulation using select for systems not providing a native - * poll implementation. - * - * Keep in mind that select is terribly inefficient. The interface is simply not - * meant to be used with maximum descriptor value greater, say, 32 or so. With - * a value as high as 1024 on Linux you'll pay dearly in every single call. - * poll() will be orders of magnitude faster. - */ -static int bsd_poll(ssh_pollfd_t *fds, nfds_t nfds, int timeout) { - fd_set readfds, writefds, exceptfds; - struct timeval tv, *ptv; - socket_t max_fd; - int rc; - nfds_t i; - - if (fds == NULL) { - errno = EFAULT; - return -1; - } - - FD_ZERO (&readfds); - FD_ZERO (&writefds); - FD_ZERO (&exceptfds); - - /* compute fd_sets and find largest descriptor */ - for (rc = -1, max_fd = 0, i = 0; i < nfds; i++) { - if (fds[i].fd == SSH_INVALID_SOCKET) { - continue; - } -#ifndef _WIN32 - if (fds[i].fd >= FD_SETSIZE) { - rc = -1; - break; - } -#endif - - if (fds[i].events & (POLLIN | POLLRDNORM)) { - FD_SET (fds[i].fd, &readfds); - } - if (fds[i].events & (POLLOUT | POLLWRNORM | POLLWRBAND)) { - FD_SET (fds[i].fd, &writefds); - } - if (fds[i].events & (POLLPRI | POLLRDBAND)) { - FD_SET (fds[i].fd, &exceptfds); - } - if (fds[i].fd > max_fd && - (fds[i].events & (POLLIN | POLLOUT | POLLPRI | - POLLRDNORM | POLLRDBAND | - POLLWRNORM | POLLWRBAND))) { - max_fd = fds[i].fd; - rc = 0; - } - } - - if (max_fd == SSH_INVALID_SOCKET || rc == -1) { - errno = EINVAL; - return -1; - } - - if (timeout < 0) { - ptv = NULL; - } else { - ptv = &tv; - if (timeout == 0) { - tv.tv_sec = 0; - tv.tv_usec = 0; - } else { - tv.tv_sec = timeout / 1000; - tv.tv_usec = (timeout % 1000) * 1000; - } - } - - rc = select (max_fd + 1, &readfds, &writefds, &exceptfds, ptv); - if (rc < 0) { - return -1; - } - - for (rc = 0, i = 0; i < nfds; i++) - if (fds[i].fd >= 0) { - fds[i].revents = 0; - - if (FD_ISSET(fds[i].fd, &readfds)) { - int save_errno = errno; - char data[64] = {0}; - int ret; - - /* support for POLLHUP */ - ret = recv(fds[i].fd, data, 64, MSG_PEEK); -#ifdef _WIN32 - if ((ret == -1) && - (errno == WSAESHUTDOWN || errno == WSAECONNRESET || - errno == WSAECONNABORTED || errno == WSAENETRESET)) { -#else - if ((ret == -1) && - (errno == ESHUTDOWN || errno == ECONNRESET || - errno == ECONNABORTED || errno == ENETRESET)) { -#endif - fds[i].revents |= POLLHUP; - } else { - fds[i].revents |= fds[i].events & (POLLIN | POLLRDNORM); - } - - errno = save_errno; - } - if (FD_ISSET(fds[i].fd, &writefds)) { - fds[i].revents |= fds[i].events & (POLLOUT | POLLWRNORM | POLLWRBAND); - } - - if (FD_ISSET(fds[i].fd, &exceptfds)) { - fds[i].revents |= fds[i].events & (POLLPRI | POLLRDBAND); - } - - if (fds[i].revents & ~POLLHUP) { - rc++; - } - } else { - fds[i].revents = POLLNVAL; - } - - return rc; -} - -void ssh_poll_init(void) { - ssh_poll_emu = bsd_poll; - -#ifdef _WIN32 - hlib = LoadLibrary(WS2_LIBRARY); - if (hlib != NULL) { - wsa_poll = (WSAPoll_FunctionType) (void *) GetProcAddress(hlib, "WSAPoll"); - } -#endif /* _WIN32 */ - - if (wsa_poll != NULL) { - ssh_poll_emu = bsd_poll; - } -} - -void ssh_poll_cleanup(void) { - ssh_poll_emu = bsd_poll; -#ifdef _WIN32 - wsa_poll = NULL; - - FreeLibrary(hlib); - - hlib = NULL; -#endif /* _WIN32 */ -} - -int ssh_poll(ssh_pollfd_t *fds, nfds_t nfds, int timeout) { - return (ssh_poll_emu)(fds, nfds, timeout); -} - -#endif /* HAVE_POLL */ - -/** - * @brief Allocate a new poll object, which could be used within a poll context. - * - * @param fd Socket that will be polled. - * @param events Poll events that will be monitored for the socket. i.e. - * POLLIN, POLLPRI, POLLOUT, POLLERR, POLLHUP, POLLNVAL - * @param cb Function to be called if any of the events are set. - * @param userdata Userdata to be passed to the callback function. NULL if - * not needed. - * - * @return A new poll object, NULL on error - */ - -ssh_poll_handle ssh_poll_new(socket_t fd, short events, ssh_poll_callback cb, - void *userdata) { - ssh_poll_handle p; - - p = malloc(sizeof(struct ssh_poll_handle_struct)); - if (p != NULL) { - p->ctx = NULL; - p->x.fd = fd; - p->events = events; - p->cb = cb; - p->cb_data = userdata; - } - - return p; -} - - -/** - * @brief Free a poll object. - * - * @param p Pointer to an already allocated poll object. - */ - -void ssh_poll_free(ssh_poll_handle p) { - if(p->ctx != NULL){ - ssh_poll_ctx_remove(p->ctx,p); - p->ctx=NULL; - } - SAFE_FREE(p); -} - -/** - * @brief Get the poll context of a poll object. - * - * @param p Pointer to an already allocated poll object. - * - * @return Poll context or NULL if the poll object isn't attached. - */ -ssh_poll_ctx ssh_poll_get_ctx(ssh_poll_handle p) { - return p->ctx; -} - -/** - * @brief Get the events of a poll object. - * - * @param p Pointer to an already allocated poll object. - * - * @return Poll events. - */ -short ssh_poll_get_events(ssh_poll_handle p) { - return p->events; -} - -/** - * @brief Set the events of a poll object. The events will also be propagated - * to an associated poll context. - * - * @param p Pointer to an already allocated poll object. - * @param events Poll events. - */ -void ssh_poll_set_events(ssh_poll_handle p, short events) { - p->events = events; - if (p->ctx != NULL) { - p->ctx->pollfds[p->x.idx].events = events; - } -} - -/** - * @brief Set the file descriptor of a poll object. The FD will also be propagated - * to an associated poll context. - * - * @param p Pointer to an already allocated poll object. - * @param fd New file descriptor. - */ -void ssh_poll_set_fd(ssh_poll_handle p, socket_t fd) { - if (p->ctx != NULL) { - p->ctx->pollfds[p->x.idx].fd = fd; - } else { - p->x.fd = fd; - } -} - -/** - * @brief Add extra events to a poll object. Duplicates are ignored. - * The events will also be propagated to an associated poll context. - * - * @param p Pointer to an already allocated poll object. - * @param events Poll events. - */ -void ssh_poll_add_events(ssh_poll_handle p, short events) { - ssh_poll_set_events(p, ssh_poll_get_events(p) | events); -} - -/** - * @brief Remove events from a poll object. Non-existent are ignored. - * The events will also be propagated to an associated poll context. - * - * @param p Pointer to an already allocated poll object. - * @param events Poll events. - */ -void ssh_poll_remove_events(ssh_poll_handle p, short events) { - ssh_poll_set_events(p, ssh_poll_get_events(p) & ~events); -} - -/** - * @brief Get the raw socket of a poll object. - * - * @param p Pointer to an already allocated poll object. - * - * @return Raw socket. - */ - -socket_t ssh_poll_get_fd(ssh_poll_handle p) { - if (p->ctx != NULL) { - return p->ctx->pollfds[p->x.idx].fd; - } - - return p->x.fd; -} -/** - * @brief Set the callback of a poll object. - * - * @param p Pointer to an already allocated poll object. - * @param cb Function to be called if any of the events are set. - * @param userdata Userdata to be passed to the callback function. NULL if - * not needed. - */ -void ssh_poll_set_callback(ssh_poll_handle p, ssh_poll_callback cb, void *userdata) { - if (cb != NULL) { - p->cb = cb; - p->cb_data = userdata; - } -} - -/** - * @brief Create a new poll context. It could be associated with many poll object - * which are going to be polled at the same time as the poll context. You - * would need a single poll context per thread. - * - * @param chunk_size The size of the memory chunk that will be allocated, when - * more memory is needed. This is for efficiency reasons, - * i.e. don't allocate memory for each new poll object, but - * for the next 5. Set it to 0 if you want to use the - * library's default value. - */ -ssh_poll_ctx ssh_poll_ctx_new(size_t chunk_size) { - ssh_poll_ctx ctx; - - ctx = malloc(sizeof(struct ssh_poll_ctx_struct)); - if (ctx != NULL) { - if (!chunk_size) { - chunk_size = SSH_POLL_CTX_CHUNK; - } - - ctx->chunk_size = chunk_size; - ctx->pollptrs = NULL; - ctx->pollfds = NULL; - ctx->polls_allocated = 0; - ctx->polls_used = 0; - } - - return ctx; -} - -/** - * @brief Free a poll context. - * - * @param ctx Pointer to an already allocated poll context. - */ -void ssh_poll_ctx_free(ssh_poll_ctx ctx) { - if (ctx->polls_allocated > 0) { - register size_t i, used; - - used = ctx->polls_used; - for (i = 0; i < used; ) { - ssh_poll_handle p = ctx->pollptrs[i]; - socket_t fd = ctx->pollfds[i].fd; - - /* force poll object removal */ - if (p->cb(p, fd, POLLERR, p->cb_data) < 0) { - used = ctx->polls_used; - } else { - i++; - } - } - - SAFE_FREE(ctx->pollptrs); - SAFE_FREE(ctx->pollfds); - } - - SAFE_FREE(ctx); -} - -static int ssh_poll_ctx_resize(ssh_poll_ctx ctx, size_t new_size) { - ssh_poll_handle *pollptrs; - ssh_pollfd_t *pollfds; - - pollptrs = realloc(ctx->pollptrs, sizeof(ssh_poll_handle *) * new_size); - if (pollptrs == NULL) { - return -1; - } - - pollfds = realloc(ctx->pollfds, sizeof(ssh_pollfd_t) * new_size); - if (pollfds == NULL) { - ctx->pollptrs = realloc(pollptrs, sizeof(ssh_poll_handle *) * ctx->polls_allocated); - return -1; - } - - ctx->pollptrs = pollptrs; - ctx->pollfds = pollfds; - ctx->polls_allocated = new_size; - - return 0; -} - -/** - * @brief Add a poll object to a poll context. - * - * @param ctx Pointer to an already allocated poll context. - * @param p Pointer to an already allocated poll object. - * - * @return 0 on success, < 0 on error - */ -int ssh_poll_ctx_add(ssh_poll_ctx ctx, ssh_poll_handle p) { - socket_t fd; - - if (p->ctx != NULL) { - /* already attached to a context */ - return -1; - } - - if (ctx->polls_used == ctx->polls_allocated && - ssh_poll_ctx_resize(ctx, ctx->polls_allocated + ctx->chunk_size) < 0) { - return -1; - } - - fd = p->x.fd; - p->x.idx = ctx->polls_used++; - ctx->pollptrs[p->x.idx] = p; - ctx->pollfds[p->x.idx].fd = fd; - ctx->pollfds[p->x.idx].events = p->events; - ctx->pollfds[p->x.idx].revents = 0; - p->ctx = ctx; - - return 0; -} - -/** - * @brief Add a socket object to a poll context. - * - * @param ctx Pointer to an already allocated poll context. - * @param s A SSH socket handle - * - * @return 0 on success, < 0 on error - */ -int ssh_poll_ctx_add_socket (ssh_poll_ctx ctx, ssh_socket s) { - ssh_poll_handle p_in, p_out; - int ret; - p_in=ssh_socket_get_poll_handle_in(s); - if(p_in==NULL) - return -1; - ret = ssh_poll_ctx_add(ctx,p_in); - if(ret != 0) - return ret; - p_out=ssh_socket_get_poll_handle_out(s); - if(p_in != p_out) - ret = ssh_poll_ctx_add(ctx,p_out); - return ret; -} - - -/** - * @brief Remove a poll object from a poll context. - * - * @param ctx Pointer to an already allocated poll context. - * @param p Pointer to an already allocated poll object. - */ -void ssh_poll_ctx_remove(ssh_poll_ctx ctx, ssh_poll_handle p) { - size_t i; - - i = p->x.idx; - p->x.fd = ctx->pollfds[i].fd; - p->ctx = NULL; - - ctx->polls_used--; - - /* fill the empty poll slot with the last one */ - if (ctx->polls_used > 0 && ctx->polls_used != i) { - ctx->pollfds[i] = ctx->pollfds[ctx->polls_used]; - ctx->pollptrs[i] = ctx->pollptrs[ctx->polls_used]; - } - - /* this will always leave at least chunk_size polls allocated */ - if (ctx->polls_allocated - ctx->polls_used > ctx->chunk_size) { - ssh_poll_ctx_resize(ctx, ctx->polls_allocated - ctx->chunk_size); - } -} - -/** - * @brief Poll all the sockets associated through a poll object with a - * poll context. If any of the events are set after the poll, the - * call back function of the socket will be called. - * This function should be called once within the programs main loop. - * - * @param ctx Pointer to an already allocated poll context. - * @param timeout An upper limit on the time for which ssh_poll_ctx() will - * block, in milliseconds. Specifying a negative value - * means an infinite timeout. This parameter is passed to - * the poll() function. - * @returns SSH_OK No error. - * SSH_ERROR Error happened during the poll. - */ - -int ssh_poll_ctx_dopoll(ssh_poll_ctx ctx, int timeout) { - int rc; - int i, used; - ssh_poll_handle p; - socket_t fd; - int revents; - - if (!ctx->polls_used) - return 0; - - rc = ssh_poll(ctx->pollfds, ctx->polls_used, timeout); - if(rc < 0) - rc=SSH_ERROR; - if(rc <= 0) - return rc; - used = ctx->polls_used; - for (i = 0; i < used && rc > 0; ) { - if (!ctx->pollfds[i].revents) { - i++; - } else { - p = ctx->pollptrs[i]; - fd = ctx->pollfds[i].fd; - revents = ctx->pollfds[i].revents; - - if (p->cb(p, fd, revents, p->cb_data) < 0) { - /* the poll was removed, reload the used counter and start again */ - used = ctx->polls_used; - i=0; - } else { - ctx->pollfds[i].revents = 0; - i++; - } - - rc--; - } - } - - return rc; -} - -/** @internal - * @brief returns a pointer to the global poll context. - * Allocates it if it does not exist. - * @param session an optional session handler, used to store the error - * message if needed. - * @returns pointer to the global poll context. - */ -ssh_poll_ctx ssh_get_global_poll_ctx(ssh_session session){ - if(global_poll_ctx != NULL) - return global_poll_ctx; - global_poll_ctx=ssh_poll_ctx_new(5); - if(global_poll_ctx == NULL && session != NULL){ - ssh_set_error_oom(session); - return NULL; - } - return global_poll_ctx; -} - -/** @internal - * @brief Deallocate the global poll context - */ -void ssh_free_global_poll_ctx(){ - if(global_poll_ctx != NULL){ - ssh_poll_ctx_free(global_poll_ctx); - global_poll_ctx=NULL; - } -} - -/** @} */ - -/* vim: set ts=4 sw=4 et cindent: */ |