Mercurial > hg > octave-nkf > gnulib-hg
changeset 11852:c9032834d889
Fix polling for writeability of a screen buffer.
* lib/poll.c: Distinguish input and screen buffers for the
Win32 implementation.
* lib/select.c: Likewise.
author | Paolo Bonzini <bonzini@gnu.org> |
---|---|
date | Tue, 04 Aug 2009 18:06:07 +0200 |
parents | c9727d4e7e5a |
children | 97a383c7cec4 |
files | ChangeLog lib/poll.c lib/select.c |
diffstat | 3 files changed, 123 insertions(+), 42 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2009-08-20 Paolo Bonzini <bonzini@gnu.org> + + Fix polling for writeability of a screen buffer. + * lib/poll.c: Distinguish input and screen buffers for the + Win32 implementation. + * lib/select.c: Likewise. + 2009-08-19 Eric Blake <ebb9@byu.net> popen-safer: prevent popen from clobbering std descriptors
--- a/lib/poll.c +++ b/lib/poll.c @@ -67,6 +67,23 @@ #ifdef WIN32_NATIVE +#define IsConsoleHandle(h) (((long) (h) & 3) == 3) + +static BOOL +IsSocketHandle(HANDLE h) +{ + WSANETWORKEVENTS ev; + + if (IsConsoleHandle (h)) + return FALSE; + + /* Under Wine, it seems that getsockopt returns 0 for pipes too. + WSAEnumNetworkEvents instead distinguishes the two correctly. */ + ev.lNetworkEvents = 0xDEADBEEF; + WSAEnumNetworkEvents ((SOCKET) h, NULL, &ev); + return ev.lNetworkEvents != 0xDEADBEEF; +} + /* Declare data structures for ntdll functions. */ typedef struct _FILE_PIPE_LOCAL_INFORMATION { ULONG NamedPipeType; @@ -101,10 +118,11 @@ # define PIPE_BUF 512 # endif -/* Compute revents values for file handle H. */ +/* Compute revents values for file handle H. If some events cannot happen + for the handle, eliminate them from *P_SOUGHT. */ static int -win32_compute_revents (HANDLE h, int sought) +win32_compute_revents (HANDLE h, int *p_sought) { int i, ret, happened; INPUT_RECORD *irbuffer; @@ -130,7 +148,7 @@ if (PeekNamedPipe (h, NULL, 0, NULL, &avail, NULL) != 0) { if (avail) - happened |= sought & (POLLIN | POLLRDNORM); + happened |= *p_sought & (POLLIN | POLLRDNORM); } else @@ -151,18 +169,25 @@ || fpli.WriteQuotaAvailable >= PIPE_BUF || (fpli.OutboundQuota < PIPE_BUF && fpli.WriteQuotaAvailable == fpli.OutboundQuota)) - happened |= sought & (POLLOUT | POLLWRNORM | POLLWRBAND); + happened |= *p_sought & (POLLOUT | POLLWRNORM | POLLWRBAND); } return happened; case FILE_TYPE_CHAR: ret = WaitForSingleObject (h, 0); - if (ret == WAIT_OBJECT_0) - { - nbuffer = avail = 0; - bRet = GetNumberOfConsoleInputEvents (h, &nbuffer); - if (!bRet || nbuffer == 0) + if (!IsConsoleHandle (h)) + return ret == WAIT_OBJECT_0 ? *p_sought & ~(POLLPRI | POLLRDBAND) : 0; + + nbuffer = avail = 0; + bRet = GetNumberOfConsoleInputEvents (h, &nbuffer); + if (bRet) + { + /* Input buffer. */ + *p_sought &= POLLIN | POLLRDNORM; + if (nbuffer == 0) return POLLHUP; + if (!*p_sought) + return 0; irbuffer = (INPUT_RECORD *) alloca (nbuffer * sizeof (INPUT_RECORD)); bRet = PeekConsoleInput (h, irbuffer, nbuffer, &avail); @@ -171,19 +196,23 @@ for (i = 0; i < avail; i++) if (irbuffer[i].EventType == KEY_EVENT) - return sought & ~(POLLPRI | POLLRDBAND); + return *p_sought; + return 0; } - break; + else + { + /* Screen buffer. */ + *p_sought &= POLLOUT | POLLWRNORM | POLLWRBAND; + return *p_sought; + } default: ret = WaitForSingleObject (h, 0); if (ret == WAIT_OBJECT_0) - return sought & ~(POLLPRI | POLLRDBAND); + return *p_sought & ~(POLLPRI | POLLRDBAND); - break; + return *p_sought & (POLLOUT | POLLWRNORM | POLLWRBAND); } - - return sought & (POLLOUT | POLLWRNORM | POLLWRBAND); } /* Convert fd_sets returned by select into revents values. */ @@ -430,36 +459,32 @@ /* Classify socket handles and create fd sets. */ for (i = 0; i < nfd; i++) { + int sought = pfd[i].events; pfd[i].revents = 0; if (pfd[i].fd < 0) continue; - if (!(pfd[i].events & (POLLIN | POLLRDNORM | - POLLOUT | POLLWRNORM | POLLWRBAND))) + if (!(sought & (POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM | POLLWRBAND + | POLLPRI | POLLRDBAND))) continue; h = (HANDLE) _get_osfhandle (pfd[i].fd); assert (h != NULL); - - /* Under Wine, it seems that getsockopt returns 0 for pipes too. - WSAEnumNetworkEvents instead distinguishes the two correctly. */ - ev.lNetworkEvents = 0xDEADBEEF; - WSAEnumNetworkEvents ((SOCKET) h, NULL, &ev); - if (ev.lNetworkEvents != 0xDEADBEEF) + if (IsSocketHandle (h)) { int requested = FD_CLOSE; /* see above; socket handles are mapped onto select. */ - if (pfd[i].events & (POLLIN | POLLRDNORM)) + if (sought & (POLLIN | POLLRDNORM)) { requested |= FD_READ | FD_ACCEPT; FD_SET ((SOCKET) h, &rfds); } - if (pfd[i].events & (POLLOUT | POLLWRNORM | POLLWRBAND)) + if (sought & (POLLOUT | POLLWRNORM | POLLWRBAND)) { requested |= FD_WRITE | FD_CONNECT; FD_SET ((SOCKET) h, &wfds); } - if (pfd[i].events & (POLLPRI | POLLRDBAND)) + if (sought & (POLLPRI | POLLRDBAND)) { requested |= FD_OOB; FD_SET ((SOCKET) h, &xfds); @@ -470,10 +495,13 @@ } else { - handle_array[nhandles++] = h; - - /* Poll now. If we get an event, do not poll again. */ - pfd[i].revents = win32_compute_revents (h, pfd[i].events); + /* Poll now. If we get an event, do not poll again. Also, + screen buffer handles are waitable, and they'll block until + a character is available. win32_compute_revents eliminates + bits for the "wrong" direction. */ + pfd[i].revents = win32_compute_revents (h, &sought); + if (sought) + handle_array[nhandles++] = h; if (pfd[i].revents) wait_timeout = 0; } @@ -553,8 +581,9 @@ else { /* Not a socket. */ + int sought = pfd[i].events; + happened = win32_compute_revents (h, &sought); nhandles++; - happened = win32_compute_revents (h, pfd[i].events); } if ((pfd[i].revents |= happened) != 0)
--- a/lib/select.c +++ b/lib/select.c @@ -21,6 +21,7 @@ #include <config.h> #include <alloca.h> +#include <assert.h> #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ /* Native Win32. */ @@ -76,6 +77,23 @@ #define PIPE_BUF 512 #endif +#define IsConsoleHandle(h) (((long) (h) & 3) == 3) + +static BOOL +IsSocketHandle(HANDLE h) +{ + WSANETWORKEVENTS ev; + + if (IsConsoleHandle (h)) + return FALSE; + + /* Under Wine, it seems that getsockopt returns 0 for pipes too. + WSAEnumNetworkEvents instead distinguishes the two correctly. */ + ev.lNetworkEvents = 0xDEADBEEF; + WSAEnumNetworkEvents ((SOCKET) h, NULL, &ev); + return ev.lNetworkEvents != 0xDEADBEEF; +} + /* Compute output fd_sets for libc descriptor FD (whose Win32 handle is H). */ static int @@ -138,19 +156,37 @@ break; case FILE_TYPE_CHAR: + write = TRUE; + if (!(rbits->in[fd / CHAR_BIT] & (1 << (fd & (CHAR_BIT - 1))))) + break; + ret = WaitForSingleObject (h, 0); - write = TRUE; if (ret == WAIT_OBJECT_0) { + if (!IsConsoleHandle (h)) + { + read = TRUE; + break; + } + nbuffer = avail = 0; bRet = GetNumberOfConsoleInputEvents (h, &nbuffer); - if (!bRet || nbuffer == 0) - except = TRUE; + + /* Screen buffers handles are filtered earlier. */ + assert (bRet); + if (nbuffer == 0) + { + except = TRUE; + break; + } irbuffer = (INPUT_RECORD *) alloca (nbuffer * sizeof (INPUT_RECORD)); bRet = PeekConsoleInput (h, irbuffer, nbuffer, &avail); if (!bRet || avail == 0) - except = TRUE; + { + except = TRUE; + break; + } for (i = 0; i < avail; i++) if (irbuffer[i].EventType == KEY_EVENT) @@ -199,7 +235,7 @@ fd_set handle_rfds, handle_wfds, handle_xfds; struct bitset rbits, wbits, xbits; unsigned char anyfds_in[FD_SETSIZE / CHAR_BIT]; - DWORD ret, wait_timeout, nhandles, nsock; + DWORD ret, wait_timeout, nhandles, nsock, nbuffer; MSG msg; int i, fd, rc; @@ -227,7 +263,10 @@ nhandles = 1; nsock = 0; - /* Copy descriptors to bitsets. */ + /* Copy descriptors to bitsets. At the same time, eliminate + bits in the "wrong" direction for console input buffers + and screen buffers, because screen buffers are waitable + and they will block until a character is available. */ memset (&rbits, 0, sizeof (rbits)); memset (&wbits, 0, sizeof (wbits)); memset (&xbits, 0, sizeof (xbits)); @@ -236,6 +275,11 @@ for (i = 0; i < rfds->fd_count; i++) { fd = rfds->fd_array[i]; + h = (HANDLE) _get_osfhandle (fd); + if (IsConsoleHandle (h) + && !GetNumberOfConsoleInputEvents (h, &nbuffer)) + continue; + rbits.in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1)); anyfds_in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1)); } @@ -246,6 +290,11 @@ for (i = 0; i < wfds->fd_count; i++) { fd = wfds->fd_array[i]; + h = (HANDLE) _get_osfhandle (fd); + if (IsConsoleHandle (h) + && GetNumberOfConsoleInputEvents (h, &nbuffer)) + continue; + wbits.in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1)); anyfds_in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1)); } @@ -285,11 +334,7 @@ return -1; } - /* Under Wine, it seems that getsockopt returns 0 for pipes too. - WSAEnumNetworkEvents instead distinguishes the two correctly. */ - ev.lNetworkEvents = 0xDEADBEEF; - WSAEnumNetworkEvents ((SOCKET) h, NULL, &ev); - if (ev.lNetworkEvents != 0xDEADBEEF) + if (IsSocketHandle (h)) { int requested = FD_CLOSE;