diff options
| -rw-r--r-- | lib/curl_setup.h | 15 | ||||
| -rw-r--r-- | lib/sendf.c | 102 | ||||
| -rw-r--r-- | lib/url.c | 46 | ||||
| -rw-r--r-- | lib/urldata.h | 17 |
4 files changed, 179 insertions, 1 deletions
diff --git a/lib/curl_setup.h b/lib/curl_setup.h index da26e48cb..d78873fe5 100644 --- a/lib/curl_setup.h +++ b/lib/curl_setup.h @@ -722,4 +722,19 @@ endings either CRLF or LF so 't' is appropriate. #define FOPEN_WRITETEXT "w" #endif +/* WinSock destroys recv() buffer when send() failed. + * Enabled automatically for Windows and for Cygwin as Cygwin sockets are + * wrappers for WinSock sockets. https://github.com/curl/curl/issues/657 + * Define DONT_USE_RECV_BEFORE_SEND_WORKAROUND to force disable workaround. + */ +#if !defined(DONT_USE_RECV_BEFORE_SEND_WORKAROUND) +# if defined(WIN32) || defined(__CYGWIN__) +# define USE_RECV_BEFORE_SEND_WORKAROUND +# endif +#else /* DONT_USE_RECV_BEFORE_SEND_WORKAROUNDS */ +# ifdef USE_RECV_BEFORE_SEND_WORKAROUND +# undef USE_RECV_BEFORE_SEND_WORKAROUND +# endif +#endif /* DONT_USE_RECV_BEFORE_SEND_WORKAROUNDS */ + #endif /* HEADER_CURL_SETUP_H */ diff --git a/lib/sendf.c b/lib/sendf.c index a75c5c743..23bcfa2c9 100644 --- a/lib/sendf.c +++ b/lib/sendf.c @@ -33,6 +33,7 @@ #include "non-ascii.h" #include "curl_printf.h" #include "strerror.h" +#include "select.h" /* The last #include files should be: */ #include "curl_memory.h" @@ -120,6 +121,90 @@ static size_t convert_lineends(struct SessionHandle *data, } #endif /* CURL_DO_LINEEND_CONV */ +#ifdef USE_RECV_BEFORE_SEND_WORKAROUND +static void pre_receive_plain(struct connectdata *conn, int num) +{ + const curl_socket_t sockfd = conn->sock[num]; + struct postponed_data * const psnd = &(conn->postponed[num]); + size_t bytestorecv = psnd->allocated_size - psnd->recv_size; + /* WinSock will destroy unread received data if send() is + failed. + To avoid lossage of received data, recv() must be + performed before every send() if any incoming data is + available. However, skip this, if buffer is already full. */ + if((conn->handler->protocol&PROTO_FAMILY_HTTP) != 0 && + conn->recv[num] == Curl_recv_plain && + (!psnd->buffer || bytestorecv)) { + const int readymask = Curl_socket_check(sockfd, CURL_SOCKET_BAD, + CURL_SOCKET_BAD, 0); + if(readymask != -1 && (readymask & CURL_CSELECT_IN) != 0) { + /* Have some incoming data */ + if(!psnd->buffer) { + /* Use buffer double default size for intermediate buffer */ + psnd->allocated_size = 2 * BUFSIZE; + psnd->buffer = malloc(psnd->allocated_size); + psnd->recv_size = 0; + psnd->recv_processed = 0; +#ifdef DEBUGBUILD + psnd->bindsock = sockfd; /* Used only for DEBUGASSERT */ +#endif /* DEBUGBUILD */ + bytestorecv = psnd->allocated_size; + } + if(psnd->buffer) { + ssize_t recvedbytes; + DEBUGASSERT(psnd->bindsock == sockfd); + recvedbytes = sread(sockfd, psnd->buffer + psnd->recv_size, + bytestorecv); + if(recvedbytes > 0) + psnd->recv_size += recvedbytes; + } + else + psnd->allocated_size = 0; + } + } +} + +static ssize_t get_pre_recved(struct connectdata *conn, int num, char *buf, + size_t len) +{ + struct postponed_data * const psnd = &(conn->postponed[num]); + size_t copysize; + if(!psnd->buffer) + return 0; + + DEBUGASSERT(psnd->allocated_size > 0); + DEBUGASSERT(psnd->recv_size <= psnd->allocated_size); + DEBUGASSERT(psnd->recv_processed <= psnd->recv_size); + /* Check and process data that already received and storied in internal + intermediate buffer */ + if(psnd->recv_size > psnd->recv_processed) { + DEBUGASSERT(psnd->bindsock == conn->sock[num]); + copysize = CURLMIN(len, psnd->recv_size - psnd->recv_processed); + memcpy(buf, psnd->buffer + psnd->recv_processed, copysize); + psnd->recv_processed += copysize; + } + else + copysize = 0; /* buffer was allocated, but nothing was received */ + + /* Free intermediate buffer if it has no unprocessed data */ + if(psnd->recv_processed == psnd->recv_size) { + free(psnd->buffer); + psnd->buffer = NULL; + psnd->allocated_size = 0; + psnd->recv_size = 0; + psnd->recv_processed = 0; +#ifdef DEBUGBUILD + psnd->bindsock = CURL_SOCKET_BAD; +#endif /* DEBUGBUILD */ + } + return (ssize_t)copysize; +} +#else /* ! USE_RECV_BEFORE_SEND_WORKAROUND */ +/* Use "do-nothing" macros instead of functions when workaround not used */ +#define pre_receive_plain(c,n) do {} WHILE_FALSE +#define get_pre_recved(c,n,b,l) 0 +#endif /* ! USE_RECV_BEFORE_SEND_WORKAROUND */ + /* Curl_infof() is for info message along the way */ void Curl_infof(struct SessionHandle *data, const char *fmt, ...) @@ -255,6 +340,12 @@ ssize_t Curl_send_plain(struct connectdata *conn, int num, { curl_socket_t sockfd = conn->sock[num]; ssize_t bytes_written; + /* WinSock will destroy unread received data if send() is + failed. + To avoid lossage of received data, recv() must be + performed before every send() if any incoming data is + available. */ + pre_receive_plain(conn, num); #ifdef MSG_FASTOPEN /* Linux */ if(conn->bits.tcp_fastopen) { @@ -322,7 +413,16 @@ ssize_t Curl_recv_plain(struct connectdata *conn, int num, char *buf, size_t len, CURLcode *code) { curl_socket_t sockfd = conn->sock[num]; - ssize_t nread = sread(sockfd, buf, len); + ssize_t nread; + /* Check and return data that already received and storied in internal + intermediate buffer */ + nread = get_pre_recved(conn, num, buf, len); + if(nread > 0) { + *code = CURLE_OK; + return nread; + } + + nread = sread(sockfd, buf, len); *code = CURLE_OK; if(-1 == nread) { @@ -2694,6 +2694,43 @@ CURLcode Curl_setopt(struct SessionHandle *data, CURLoption option, return result; } +#ifdef USE_RECV_BEFORE_SEND_WORKAROUND +static void conn_reset_postponed_data(struct connectdata *conn, int num) +{ + struct postponed_data * const psnd = &(conn->postponed[num]); + if(psnd->buffer) { + DEBUGASSERT(psnd->allocated_size > 0); + DEBUGASSERT(psnd->recv_size <= psnd->allocated_size); + DEBUGASSERT(psnd->recv_processed < psnd->recv_size); + DEBUGASSERT(psnd->bindsock != CURL_SOCKET_BAD); + free(psnd->buffer); + psnd->buffer = NULL; + psnd->allocated_size = 0; + psnd->recv_size = 0; + psnd->recv_processed = 0; +#ifdef DEBUGBUILD + psnd->bindsock = CURL_SOCKET_BAD; /* used only for DEBUGASSERT */ +#endif /* DEBUGBUILD */ + } + else { + DEBUGASSERT (psnd->allocated_size == 0); + DEBUGASSERT (psnd->recv_size == 0); + DEBUGASSERT (psnd->recv_processed == 0); + DEBUGASSERT (psnd->bindsock == CURL_SOCKET_BAD); + } +} + +static void conn_reset_all_postponed_data(struct connectdata *conn) +{ + conn_reset_postponed_data(conn, 0); + conn_reset_postponed_data(conn, 1); +} +#else /* ! USE_RECV_BEFORE_SEND_WORKAROUND */ +/* Use "do-nothing" macros instead of functions when workaround not used */ +#define conn_reset_postponed_data(c,n) do {} WHILE_FALSE +#define conn_reset_all_postponed_data(c) do {} WHILE_FALSE +#endif /* ! USE_RECV_BEFORE_SEND_WORKAROUND */ + static void conn_free(struct connectdata *conn) { if(!conn) @@ -2744,6 +2781,8 @@ static void conn_free(struct connectdata *conn) Curl_safefree(conn->proxy.rawalloc); /* proxy name buffer */ Curl_safefree(conn->master_buffer); + conn_reset_all_postponed_data(conn); + Curl_llist_destroy(conn->send_pipe, NULL); Curl_llist_destroy(conn->recv_pipe, NULL); @@ -3851,6 +3890,10 @@ static struct connectdata *allocate_conn(struct SessionHandle *data) conn->connection_id = -1; /* no ID */ conn->port = -1; /* unknown at this point */ conn->remote_port = -1; /* unknown */ +#if defined(USE_RECV_BEFORE_SEND_WORKAROUND) && defined(DEBUGBUILD) + conn->postponed[0].bindsock = CURL_SOCKET_BAD; /* no file descriptor */ + conn->postponed[1].bindsock = CURL_SOCKET_BAD; /* no file descriptor */ +#endif /* USE_RECV_BEFORE_SEND_WORKAROUND && DEBUGBUILD */ /* Default protocol-independent behavior doesn't support persistent connections, so we set this to force-close. Protocols that support @@ -5625,6 +5668,9 @@ static void reuse_conn(struct connectdata *old_conn, /* persist connection info in session handle */ Curl_persistconninfo(conn); + conn_reset_all_postponed_data(old_conn); /* free buffers */ + conn_reset_all_postponed_data(conn); /* reset unprocessed data */ + /* re-use init */ conn->bits.reuse = TRUE; /* yes, we're re-using here */ diff --git a/lib/urldata.h b/lib/urldata.h index 016761929..f190fbdd6 100644 --- a/lib/urldata.h +++ b/lib/urldata.h @@ -833,6 +833,20 @@ typedef ssize_t (Curl_recv)(struct connectdata *conn, /* connection data */ size_t len, /* max amount to read */ CURLcode *err); /* error to return */ +#ifdef USE_RECV_BEFORE_SEND_WORKAROUND +struct postponed_data { + char *buffer; /* Temporal store for received data during + sending, must be freed */ + size_t allocated_size; /* Size of temporal store */ + size_t recv_size; /* Size of received data during sending */ + size_t recv_processed; /* Size of processed part of postponed data */ +#ifdef DEBUGBUILD + curl_socket_t bindsock;/* Structure must be bound to specific socket, + used only for DEBUGASSERT */ +#endif /* DEBUGBUILD */ +}; +#endif /* USE_RECV_BEFORE_SEND_WORKAROUND */ + /* * The connectdata struct contains all fields and variables that should be * unique for an entire connection. @@ -931,6 +945,9 @@ struct connectdata { Curl_recv *recv[2]; Curl_send *send[2]; +#ifdef USE_RECV_BEFORE_SEND_WORKAROUND + struct postponed_data postponed[2]; /* two buffers for two sockets */ +#endif /* USE_RECV_BEFORE_SEND_WORKAROUND */ struct ssl_connect_data ssl[2]; /* this is for ssl-stuff */ struct ssl_config_data ssl_config; bool tls_upgraded; |