diff options
Diffstat (limited to 'gdb/mingw-hdep.c')
| -rw-r--r-- | gdb/mingw-hdep.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/gdb/mingw-hdep.c b/gdb/mingw-hdep.c index 1318cfd..79b23dc 100644 --- a/gdb/mingw-hdep.c +++ b/gdb/mingw-hdep.c @@ -21,7 +21,10 @@ Boston, MA 02110-1301, USA. */ #include "defs.h" +#include "serial.h" +#include "gdb_assert.h" +#include "gdb_select.h" #include "gdb_string.h" #include <windows.h> @@ -69,3 +72,124 @@ safe_strerror (int errnum) return buffer; } + +/* Wrapper for select. On Windows systems, where the select interface + only works for sockets, this uses the GDB serial abstraction to + handle sockets, consoles, pipes, and serial ports. + + The arguments to this function are the same as the traditional + arguments to select on POSIX platforms. */ + +int +gdb_select (int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, + struct timeval *timeout) +{ + static HANDLE never_handle; + HANDLE handles[MAXIMUM_WAIT_OBJECTS]; + HANDLE h; + DWORD event; + DWORD num_handles; + int fd; + int num_ready; + int indx; + + num_ready = 0; + num_handles = 0; + for (fd = 0; fd < n; ++fd) + { + HANDLE read = NULL, except = NULL; + struct serial *scb; + + /* There is no support yet for WRITEFDS. At present, this isn't + used by GDB -- but we do not want to silently ignore WRITEFDS + if something starts using it. */ + gdb_assert (!writefds || !FD_ISSET (fd, writefds)); + + if (!FD_ISSET (fd, readfds) + && !FD_ISSET (fd, exceptfds)) + continue; + h = (HANDLE) _get_osfhandle (fd); + + scb = serial_for_fd (fd); + if (scb) + serial_wait_handle (scb, &read, &except); + + if (read == NULL) + read = h; + if (except == NULL) + { + if (!never_handle) + never_handle = CreateEvent (0, FALSE, FALSE, 0); + + except = never_handle; + } + + if (FD_ISSET (fd, readfds)) + { + gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS); + handles[num_handles++] = read; + } + + if (FD_ISSET (fd, exceptfds)) + { + gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS); + handles[num_handles++] = except; + } + } + /* If we don't need to wait for any handles, we are done. */ + if (!num_handles) + { + if (timeout) + Sleep (timeout->tv_sec * 1000 + timeout->tv_usec / 1000); + + return 0; + } + + event = WaitForMultipleObjects (num_handles, + handles, + FALSE, + timeout + ? (timeout->tv_sec * 1000 + + timeout->tv_usec / 1000) + : INFINITE); + /* EVENT can only be a value in the WAIT_ABANDONED_0 range if the + HANDLES included an abandoned mutex. Since GDB doesn't use + mutexes, that should never occur. */ + gdb_assert (!(WAIT_ABANDONED_0 <= event + && event < WAIT_ABANDONED_0 + num_handles)); + if (event == WAIT_FAILED) + return -1; + if (event == WAIT_TIMEOUT) + return 0; + /* Run through the READFDS, clearing bits corresponding to descriptors + for which input is unavailable. */ + h = handles[event - WAIT_OBJECT_0]; + for (fd = 0, indx = 0; fd < n; ++fd) + { + HANDLE fd_h; + + if (FD_ISSET (fd, readfds)) + { + fd_h = handles[indx++]; + /* This handle might be ready, even though it wasn't the handle + returned by WaitForMultipleObjects. */ + if (fd_h != h && WaitForSingleObject (fd_h, 0) != WAIT_OBJECT_0) + FD_CLR (fd, readfds); + else + num_ready++; + } + + if (FD_ISSET (fd, exceptfds)) + { + fd_h = handles[indx++]; + /* This handle might be ready, even though it wasn't the handle + returned by WaitForMultipleObjects. */ + if (fd_h != h && WaitForSingleObject (fd_h, 0) != WAIT_OBJECT_0) + FD_CLR (fd, exceptfds); + else + num_ready++; + } + } + + return num_ready; +} |