[llvm-commits] [llvm] r103153 - /llvm/trunk/lib/Support/raw_ostream.cpp
Dan Gohman
gohman at apple.com
Wed May 5 18:27:36 PDT 2010
Author: djg
Date: Wed May 5 20:27:36 2010
New Revision: 103153
URL: http://llvm.org/viewvc/llvm-project?rev=103153&view=rev
Log:
Handle EWOULDBLOCK as EAGAIN. And add a comment explaining why
EAGAIN and EWOULDBLOCK are used here.
Also, handle the case where a write call is interrupted after
some data has already been written.
Modified:
llvm/trunk/lib/Support/raw_ostream.cpp
Modified: llvm/trunk/lib/Support/raw_ostream.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/raw_ostream.cpp?rev=103153&r1=103152&r2=103153&view=diff
==============================================================================
--- llvm/trunk/lib/Support/raw_ostream.cpp (original)
+++ llvm/trunk/lib/Support/raw_ostream.cpp Wed May 5 20:27:36 2010
@@ -422,11 +422,30 @@
assert(FD >= 0 && "File already closed.");
pos += Size;
ssize_t ret;
+
do {
ret = ::write(FD, Ptr, Size);
- } while (ret < 0 && (errno == EAGAIN || errno == EINTR));
- if (ret != (ssize_t) Size)
- error_detected();
+
+ if (ret < 0) {
+ // If it's a recoverable error, swallow it and retry the write.
+ // EAGAIN and EWOULDBLOCK are not unambiguously recoverable, but
+ // some programs, such as bjam, assume that their child processes
+ // will treat them as if they are. If you don't want this code to
+ // spin, don't use O_NONBLOCK file descriptors with raw_ostream.
+ if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)
+ continue;
+
+ // Otherwise it's a non-recoverable error. Note it and quit.
+ error_detected();
+ break;
+ }
+
+ // The write may have written some or all of the data. Update the
+ // size and buffer pointer to reflect the remainder that needs
+ // to be written. If there are no bytes left, we're done.
+ Ptr += ret;
+ Size -= ret;
+ } while (Size > 0);
}
void raw_fd_ostream::close() {
More information about the llvm-commits
mailing list