diff options
| -rw-r--r-- | src/ChangeLog | 10 | ||||
| -rw-r--r-- | src/gpgcedev.c | 71 |
2 files changed, 81 insertions, 0 deletions
diff --git a/src/ChangeLog b/src/ChangeLog index fd2a293..dc20d24 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,13 @@ +2010-06-09 Marcus Brinkmann <[email protected]> + + * gpgcedev.c (GPGCEDEV_IOCTL_UNBLOCK): New ioctl. + (PIPE_FLAG_UNBLOCK_READER, PIPE_FLAG_UNBLOCK_WRITER): New flags. + (GPG_Read): Check if PIPE_FLAG_UNBLOCK_READER is set and return + ERROR_BUSY in that case. + (GPG_Write): Likewise for PIPE_FLAG_UNBLOCK_WRITER. + (unblock_call): New function. + (GPG_IOControl): Implement GPGCEDEV_IOCTL_UNBLOCK. + 2010-06-07 Marcus Brinkmann <[email protected]> * gpgcedev.c: This rewrite does away with troublesome race diff --git a/src/gpgcedev.c b/src/gpgcedev.c index 357c488..c0feda9 100644 --- a/src/gpgcedev.c +++ b/src/gpgcedev.c @@ -54,6 +54,17 @@ #define GPGCEDEV_IOCTL_MAKE_PIPE \ CTL_CODE (FILE_DEVICE_STREAMS, 2049, METHOD_BUFFERED, FILE_ANY_ACCESS) +/* The IOCTL used to unblock a blocking thread. + + The caller sends this IOCTL to the read or the write handle. No + parameter is required. The effect is that a reader or writer + blocked on the same handle is unblocked (and will return + ERROR_BUSY). Note that the operation can be repeated, if so + desired. The state of the pipe itself will not be affected in any + way. */ +#define GPGCEDEV_IOCTL_UNBLOCK \ + CTL_CODE (FILE_DEVICE_STREAMS, 2050, METHOD_BUFFERED, FILE_ANY_ACCESS) + struct pipeimpl_s { CRITICAL_SECTION critsect; /* Lock for all members. */ @@ -66,6 +77,8 @@ struct pipeimpl_s #define PIPE_FLAG_NO_READER 1 #define PIPE_FLAG_NO_WRITER 2 +#define PIPE_FLAG_UNBLOCK_READER 4 +#define PIPE_FLAG_UNBLOCK_WRITER 8 int flags; HANDLE space_available; /* Set if space is available. */ @@ -488,6 +501,16 @@ GPG_Read (DWORD opnctx_arg, void *buffer, DWORD count) goto leave; } + /* Check for request to unblock once. */ + if (pimpl->flags & PIPE_FLAG_UNBLOCK_READER) + { + log_debug ("GPG_Read (ctx=0x%p): success: EBUSY (due to unblock request)\n", (void*)ctx); + pimpl->flags &= ~PIPE_FLAG_UNBLOCK_READER; + SetLastError (ERROR_BUSY); + result = -1; + goto leave; + } + LeaveCriticalSection (&pimpl->critsect); log_debug ("GPG_Read (ctx=0x%p): waiting: data_available\n", (void*)ctx); WaitForSingleObject (data_available, INFINITE); @@ -561,6 +584,16 @@ GPG_Write (DWORD opnctx_arg, const void *buffer, DWORD count) goto leave; } + /* Check for request to unblock once. */ + if (pimpl->flags & PIPE_FLAG_UNBLOCK_WRITER) + { + log_debug ("GPG_Write (ctx=0x%p): success: EBUSY (due to unblock request)\n", (void*)ctx); + pimpl->flags &= ~PIPE_FLAG_UNBLOCK_WRITER; + SetLastError (ERROR_BUSY); + result = -1; + goto leave; + } + /* Write to our buffer. */ if (pimpl->buffer_len == pimpl->buffer_size) { @@ -695,6 +728,30 @@ make_pipe (opnctx_t ctx, LONG rvid) } +/* opnctx_table_s is locked on entering and on exit. */ +static BOOL +unblock_call (opnctx_t ctx) +{ + /* If there is no pipe object, no thread can be blocked. */ + if (!ctx->pipeimpl) + return TRUE; + + EnterCriticalSection (&ctx->pipeimpl->critsect); + if (ctx->access_code & GENERIC_READ) + { + ctx->pipeimpl->flags |= PIPE_FLAG_UNBLOCK_READER; + SetEvent (ctx->pipeimpl->data_available); + } + else if (ctx->access_code & GENERIC_WRITE) + { + ctx->pipeimpl->flags |= PIPE_FLAG_UNBLOCK_WRITER; + SetEvent (ctx->pipeimpl->space_available); + } + LeaveCriticalSection (&ctx->pipeimpl->critsect); + + return TRUE; +} + BOOL GPG_IOControl (DWORD opnctx_arg, DWORD code, void *inbuf, DWORD inbuflen, void *outbuf, DWORD outbuflen, DWORD *actualoutlen) @@ -754,6 +811,20 @@ GPG_IOControl (DWORD opnctx_arg, DWORD code, void *inbuf, DWORD inbuflen, result = TRUE; break; + case GPGCEDEV_IOCTL_UNBLOCK: + log_debug ("GPG_IOControl (ctx=0x%p): code: UNBLOCK\n", (void*)opnctx); + if (inbuf || inbuflen || outbuf || outbuflen || actualoutlen) + { + log_debug ("GPG_IOControl (ctx=0x%p): error: invalid parameter\n", + (void*)opnctx); + SetLastError (ERROR_INVALID_PARAMETER); + goto leave; + } + + if (unblock_call (opnctx)) + result = TRUE; + break; + case IOCTL_PSL_NOTIFY: log_debug ("GPG_IOControl (ctx=0x%p): code: NOTIFY\n", (void*)opnctx); /* Unexpected process termination. */ |