From 80ab0233688c9df9fd48265b6f9e7ab7cd589dbc Mon Sep 17 00:00:00 2001 From: dec05eba Date: Sat, 19 Aug 2023 23:50:04 +0200 Subject: Initial commit --- depends/libxcb/src/xcb_out.c | 501 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 501 insertions(+) create mode 100644 depends/libxcb/src/xcb_out.c (limited to 'depends/libxcb/src/xcb_out.c') diff --git a/depends/libxcb/src/xcb_out.c b/depends/libxcb/src/xcb_out.c new file mode 100644 index 0000000..a4fe823 --- /dev/null +++ b/depends/libxcb/src/xcb_out.c @@ -0,0 +1,501 @@ +/* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Except as contained in this notice, the names of the authors or their + * institutions shall not be used in advertising or otherwise to promote the + * sale, use or other dealings in this Software without prior written + * authorization from the authors. + */ + +/* Stuff that sends stuff to the server. */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include +#include +#ifdef _WIN32 +#include +#else +#include +#endif +#include + +#include "xcb.h" +#include "xcbext.h" +#include "xcbint.h" +#include "bigreq.h" + +static inline void send_request(xcb_connection_t *c, int isvoid, enum workarounds workaround, int flags, struct iovec *vector, int count) +{ + if(c->has_error) + return; + + ++c->out.request; + if(!isvoid) + c->in.request_expected = c->out.request; + if(workaround != WORKAROUND_NONE || flags != 0) + _xcb_in_expect_reply(c, c->out.request, workaround, flags); + + while(count && c->out.queue_len + vector[0].iov_len <= sizeof(c->out.queue)) + { + memcpy(c->out.queue + c->out.queue_len, vector[0].iov_base, vector[0].iov_len); + c->out.queue_len += vector[0].iov_len; + vector[0].iov_base = (char *) vector[0].iov_base + vector[0].iov_len; + vector[0].iov_len = 0; + ++vector, --count; + } + if(!count) + return; + + --vector, ++count; + vector[0].iov_base = c->out.queue; + vector[0].iov_len = c->out.queue_len; + c->out.queue_len = 0; + _xcb_out_send(c, vector, count); +} + +static void send_sync(xcb_connection_t *c) +{ + static const union { + struct { + uint8_t major; + uint8_t pad; + uint16_t len; + } fields; + uint32_t packet; + } sync_req = { { /* GetInputFocus */ 43, 0, 1 } }; + struct iovec vector[2]; + vector[1].iov_base = (char *) &sync_req; + vector[1].iov_len = sizeof(sync_req); + send_request(c, 0, WORKAROUND_NONE, XCB_REQUEST_DISCARD_REPLY, vector + 1, 1); +} + +static void get_socket_back(xcb_connection_t *c) +{ + while(c->out.return_socket && c->out.socket_moving) + pthread_cond_wait(&c->out.socket_cond, &c->iolock); + if(!c->out.return_socket) + return; + + c->out.socket_moving = 1; + pthread_mutex_unlock(&c->iolock); + c->out.return_socket(c->out.socket_closure); + pthread_mutex_lock(&c->iolock); + c->out.socket_moving = 0; + + pthread_cond_broadcast(&c->out.socket_cond); + c->out.return_socket = 0; + c->out.socket_closure = 0; + _xcb_in_replies_done(c); +} + +static void prepare_socket_request(xcb_connection_t *c) +{ + /* We're about to append data to out.queue, so we need to + * atomically test for an external socket owner *and* some other + * thread currently writing. + * + * If we have an external socket owner, we have to get the socket back + * before we can use it again. + * + * If some other thread is writing to the socket, we assume it's + * writing from out.queue, and so we can't stick data there. + * + * We satisfy this condition by first calling get_socket_back + * (which may drop the lock, but will return when XCB owns the + * socket again) and then checking for another writing thread and + * escaping the loop if we're ready to go. + */ + for (;;) { + if(c->has_error) + return; + get_socket_back(c); + if (!c->out.writing) + break; + pthread_cond_wait(&c->out.cond, &c->iolock); + } +} + +/* Public interface */ + +void xcb_prefetch_maximum_request_length(xcb_connection_t *c) +{ + if(c->has_error) + return; + pthread_mutex_lock(&c->out.reqlenlock); + if(c->out.maximum_request_length_tag == LAZY_NONE) + { + const xcb_query_extension_reply_t *ext; + ext = xcb_get_extension_data(c, &xcb_big_requests_id); + if(ext && ext->present) + { + c->out.maximum_request_length_tag = LAZY_COOKIE; + c->out.maximum_request_length.cookie = xcb_big_requests_enable(c); + } + else + { + c->out.maximum_request_length_tag = LAZY_FORCED; + c->out.maximum_request_length.value = c->setup->maximum_request_length; + } + } + pthread_mutex_unlock(&c->out.reqlenlock); +} + +uint32_t xcb_get_maximum_request_length(xcb_connection_t *c) +{ + if(c->has_error) + return 0; + xcb_prefetch_maximum_request_length(c); + pthread_mutex_lock(&c->out.reqlenlock); + if(c->out.maximum_request_length_tag == LAZY_COOKIE) + { + xcb_big_requests_enable_reply_t *r = xcb_big_requests_enable_reply(c, c->out.maximum_request_length.cookie, 0); + c->out.maximum_request_length_tag = LAZY_FORCED; + if(r) + { + c->out.maximum_request_length.value = r->maximum_request_length; + free(r); + } + else + c->out.maximum_request_length.value = c->setup->maximum_request_length; + } + pthread_mutex_unlock(&c->out.reqlenlock); + return c->out.maximum_request_length.value; +} + +static void close_fds(int *fds, unsigned int num_fds) +{ + for (unsigned int index = 0; index < num_fds; index++) + close(fds[index]); +} + +static void send_fds(xcb_connection_t *c, int *fds, unsigned int num_fds) +{ +#if HAVE_SENDMSG + /* Calling _xcb_out_flush_to() can drop the iolock and wait on a condition + * variable if another thread is currently writing (c->out.writing > 0). + * This call waits for writers to be done and thus _xcb_out_flush_to() will + * do the work itself (in which case we are a writer and + * prepare_socket_request() will wait for us to be done if another threads + * tries to send fds, too). Thanks to this, we can atomically write out FDs. + */ + prepare_socket_request(c); + + while (num_fds > 0) { + while (c->out.out_fd.nfd == XCB_MAX_PASS_FD && !c->has_error) { + /* XXX: if c->out.writing > 0, this releases the iolock and + * potentially allows other threads to interfere with their own fds. + */ + _xcb_out_flush_to(c, c->out.request); + + if (c->out.out_fd.nfd == XCB_MAX_PASS_FD) { + /* We need some request to send FDs with */ + _xcb_out_send_sync(c); + } + } + if (c->has_error) + break; + + c->out.out_fd.fd[c->out.out_fd.nfd++] = fds[0]; + fds++; + num_fds--; + } +#endif + close_fds(fds, num_fds); +} + +uint64_t xcb_send_request_with_fds64(xcb_connection_t *c, int flags, struct iovec *vector, + const xcb_protocol_request_t *req, unsigned int num_fds, int *fds) +{ + uint64_t request; + uint32_t prefix[2]; + int veclen = req->count; + enum workarounds workaround = WORKAROUND_NONE; + + if(c->has_error) { + close_fds(fds, num_fds); + return 0; + } + + assert(c != 0); + assert(vector != 0); + assert(req->count > 0); + + if(!(flags & XCB_REQUEST_RAW)) + { + static const char pad[3]; + unsigned int i; + uint16_t shortlen = 0; + size_t longlen = 0; + assert(vector[0].iov_len >= 4); + /* set the major opcode, and the minor opcode for extensions */ + if(req->ext) + { + const xcb_query_extension_reply_t *extension = xcb_get_extension_data(c, req->ext); + if(!(extension && extension->present)) + { + close_fds(fds, num_fds); + _xcb_conn_shutdown(c, XCB_CONN_CLOSED_EXT_NOTSUPPORTED); + return 0; + } + ((uint8_t *) vector[0].iov_base)[0] = extension->major_opcode; + ((uint8_t *) vector[0].iov_base)[1] = req->opcode; + } + else + ((uint8_t *) vector[0].iov_base)[0] = req->opcode; + + /* put together the length field, possibly using BIGREQUESTS */ + for(i = 0; i < req->count; ++i) + { + longlen += vector[i].iov_len; + if(!vector[i].iov_base) + { + vector[i].iov_base = (char *) pad; + assert(vector[i].iov_len <= sizeof(pad)); + } + } + assert((longlen & 3) == 0); + longlen >>= 2; + + if(longlen <= c->setup->maximum_request_length) + { + /* we don't need BIGREQUESTS. */ + shortlen = longlen; + longlen = 0; + } + else if(longlen > xcb_get_maximum_request_length(c)) + { + close_fds(fds, num_fds); + _xcb_conn_shutdown(c, XCB_CONN_CLOSED_REQ_LEN_EXCEED); + return 0; /* server can't take this; maybe need BIGREQUESTS? */ + } + + /* set the length field. */ + ((uint16_t *) vector[0].iov_base)[1] = shortlen; + if(!shortlen) + { + prefix[0] = ((uint32_t *) vector[0].iov_base)[0]; + prefix[1] = ++longlen; + vector[0].iov_base = (uint32_t *) vector[0].iov_base + 1; + vector[0].iov_len -= sizeof(uint32_t); + --vector, ++veclen; + vector[0].iov_base = prefix; + vector[0].iov_len = sizeof(prefix); + } + } + flags &= ~XCB_REQUEST_RAW; + + /* do we need to work around the X server bug described in glx.xml? */ + /* XXX: GetFBConfigs won't use BIG-REQUESTS in any sane + * configuration, but that should be handled here anyway. */ + if(req->ext && !req->isvoid && !strcmp(req->ext->name, "GLX") && + ((req->opcode == 17 && ((uint32_t *) vector[0].iov_base)[1] == 0x10004) || + req->opcode == 21)) + workaround = WORKAROUND_GLX_GET_FB_CONFIGS_BUG; + + /* get a sequence number and arrange for delivery. */ + pthread_mutex_lock(&c->iolock); + + /* send FDs before establishing a good request number, because this might + * call send_sync(), too + */ + send_fds(c, fds, num_fds); + + prepare_socket_request(c); + + /* send GetInputFocus (sync_req) when 64k-2 requests have been sent without + * a reply. + * Also send sync_req (could use NoOp) at 32-bit wrap to avoid having + * applications see sequence 0 as that is used to indicate + * an error in sending the request + */ + + while ((req->isvoid && c->out.request == c->in.request_expected + (1 << 16) - 2) || + (unsigned int) (c->out.request + 1) == 0) + { + send_sync(c); + prepare_socket_request(c); + } + + send_request(c, req->isvoid, workaround, flags, vector, veclen); + request = c->has_error ? 0 : c->out.request; + pthread_mutex_unlock(&c->iolock); + return request; +} + +/* request number are actually uint64_t internally but keep API compat with unsigned int */ +unsigned int xcb_send_request_with_fds(xcb_connection_t *c, int flags, struct iovec *vector, + const xcb_protocol_request_t *req, unsigned int num_fds, int *fds) +{ + return xcb_send_request_with_fds64(c, flags, vector, req, num_fds, fds); +} + +uint64_t xcb_send_request64(xcb_connection_t *c, int flags, struct iovec *vector, const xcb_protocol_request_t *req) +{ + return xcb_send_request_with_fds64(c, flags, vector, req, 0, NULL); +} + +/* request number are actually uint64_t internally but keep API compat with unsigned int */ +unsigned int xcb_send_request(xcb_connection_t *c, int flags, struct iovec *vector, const xcb_protocol_request_t *req) +{ + return xcb_send_request64(c, flags, vector, req); +} + +void +xcb_send_fd(xcb_connection_t *c, int fd) +{ + int fds[1] = { fd }; + + if (c->has_error) { + close(fd); + return; + } + pthread_mutex_lock(&c->iolock); + send_fds(c, &fds[0], 1); + pthread_mutex_unlock(&c->iolock); +} + +int xcb_take_socket(xcb_connection_t *c, void (*return_socket)(void *closure), void *closure, int flags, uint64_t *sent) +{ + int ret; + if(c->has_error) + return 0; + pthread_mutex_lock(&c->iolock); + get_socket_back(c); + + /* _xcb_out_flush may drop the iolock allowing other threads to + * write requests, so keep flushing until we're done + */ + do + ret = _xcb_out_flush_to(c, c->out.request); + while (ret && c->out.request != c->out.request_written); + if(ret) + { + c->out.return_socket = return_socket; + c->out.socket_closure = closure; + if(flags) { + /* c->out.request + 1 will be the first request sent by the external + * socket owner. If the socket is returned before this request is sent + * it will be detected in _xcb_in_replies_done and this pending_reply + * will be discarded. + */ + _xcb_in_expect_reply(c, c->out.request + 1, WORKAROUND_EXTERNAL_SOCKET_OWNER, flags); + } + assert(c->out.request == c->out.request_written); + *sent = c->out.request; + } + pthread_mutex_unlock(&c->iolock); + return ret; +} + +int xcb_writev(xcb_connection_t *c, struct iovec *vector, int count, uint64_t requests) +{ + int ret; + if(c->has_error) + return 0; + pthread_mutex_lock(&c->iolock); + c->out.request += requests; + ret = _xcb_out_send(c, vector, count); + pthread_mutex_unlock(&c->iolock); + return ret; +} + +int xcb_flush(xcb_connection_t *c) +{ + int ret; + if(c->has_error) + return 0; + pthread_mutex_lock(&c->iolock); + ret = _xcb_out_flush_to(c, c->out.request); + pthread_mutex_unlock(&c->iolock); + return ret; +} + +/* Private interface */ + +int _xcb_out_init(_xcb_out *out) +{ + if(pthread_cond_init(&out->socket_cond, 0)) + return 0; + out->return_socket = 0; + out->socket_closure = 0; + out->socket_moving = 0; + + if(pthread_cond_init(&out->cond, 0)) + return 0; + out->writing = 0; + + out->queue_len = 0; + + out->request = 0; + out->request_written = 0; + out->request_expected_written = 0; + + if(pthread_mutex_init(&out->reqlenlock, 0)) + return 0; + out->maximum_request_length_tag = LAZY_NONE; + + return 1; +} + +void _xcb_out_destroy(_xcb_out *out) +{ + pthread_mutex_destroy(&out->reqlenlock); + pthread_cond_destroy(&out->cond); + pthread_cond_destroy(&out->socket_cond); +} + +int _xcb_out_send(xcb_connection_t *c, struct iovec *vector, int count) +{ + int ret = 1; + while(ret && count) + ret = _xcb_conn_wait(c, &c->out.cond, &vector, &count); + c->out.request_written = c->out.request; + c->out.request_expected_written = c->in.request_expected; + pthread_cond_broadcast(&c->out.cond); + _xcb_in_wake_up_next_reader(c); + return ret; +} + +void _xcb_out_send_sync(xcb_connection_t *c) +{ + prepare_socket_request(c); + send_sync(c); +} + +int _xcb_out_flush_to(xcb_connection_t *c, uint64_t request) +{ + assert(XCB_SEQUENCE_COMPARE(request, <=, c->out.request)); + if(XCB_SEQUENCE_COMPARE(c->out.request_written, >=, request)) + return 1; + if(c->out.queue_len) + { + struct iovec vec; + vec.iov_base = c->out.queue; + vec.iov_len = c->out.queue_len; + c->out.queue_len = 0; + return _xcb_out_send(c, &vec, 1); + } + while(c->out.writing) + pthread_cond_wait(&c->out.cond, &c->iolock); + assert(XCB_SEQUENCE_COMPARE(c->out.request_written, >=, request)); + return 1; +} -- cgit v1.2.3