diff options
| -rw-r--r-- | lib/ChangeLog | 10 | ||||
| -rw-r--r-- | lib/stream.c | 29 | ||||
| -rw-r--r-- | lib/stream.h | 17 |
3 files changed, 55 insertions, 1 deletions
diff --git a/lib/ChangeLog b/lib/ChangeLog index 0627d206..ac05baba 100644 --- a/lib/ChangeLog +++ b/lib/ChangeLog @@ -1,5 +1,15 @@ 2005-02-16 Andrew J. Schorr <ajschorr@alumni.princeton.edu> + * stream.h: Declare new function stream_read_try suitable for use + with non-blocking file descriptors. Indicate that stream_read + and stream_read_unblock are deprecated. + * stream.c: (stream_read_try) New function for use with non-blocking + I/O. + (stream_recvmsg) Should return -1 if the stream is too small to + contain the data. + +2005-02-16 Andrew J. Schorr <ajschorr@alumni.princeton.edu> + * network.c: (set_nonblocking) Should check return code from fcntl(F_GETFL). diff --git a/lib/stream.c b/lib/stream.c index e15d0426..7e75f0da 100644 --- a/lib/stream.c +++ b/lib/stream.c @@ -603,6 +603,31 @@ stream_read_unblock (struct stream *s, int fd, size_t size) return nbytes; } +ssize_t +stream_read_try(struct stream *s, int fd, size_t size) +{ + ssize_t nbytes; + + STREAM_VERIFY_SANE(s); + + if (STREAM_WRITEABLE(s) < size) + { + STREAM_BOUND_WARN (s, "put"); + /* Fatal (not transient) error, since retrying will not help + (stream is too small to contain the desired data). */ + return -1; + } + + if ((nbytes = read(fd, s->data + s->endp, size)) >= 0) + { + s->endp += nbytes; + return nbytes; + } + /* Error: was it transient (return -2) or fatal (return -1)? */ + return ((errno == EAGAIN) || (errno == EWOULDBLOCK) || (errno == EINTR)) ? + -2 : -1; +} + /* Read up to smaller of size or SIZE_REMAIN() bytes to the stream, starting * from endp. * First iovec will be used to receive the data. @@ -621,7 +646,9 @@ stream_recvmsg (struct stream *s, int fd, struct msghdr *msgh, int flags, if (STREAM_WRITEABLE (s) < size) { STREAM_BOUND_WARN (s, "put"); - return 0; + /* This is a logic error in the calling code: the stream is too small + to hold the desired data! */ + return -1; } iov = &(msgh->msg_iov[0]); diff --git a/lib/stream.h b/lib/stream.h index fe45a4f5..54a16740 100644 --- a/lib/stream.h +++ b/lib/stream.h @@ -165,8 +165,25 @@ u_int32_t stream_get_ipv4 (struct stream *); #undef stream_read #undef stream_write + +/* Deprecated: assumes blocking I/O. Will be removed. + Use stream_read_try instead. */ int stream_read (struct stream *, int, size_t); + +/* Deprecated: all file descriptors should already be non-blocking. + Will be removed. Use stream_read_try instead. */ int stream_read_unblock (struct stream *, int, size_t); + +/* Read up to size bytes into the stream. + Return code: + >0: number of bytes read + 0: end-of-file + -1: fatal error + -2: transient error, should retry later (i.e. EAGAIN or EINTR) + This is suitable for use with non-blocking file descriptors. + */ +extern ssize_t stream_read_try(struct stream *s, int fd, size_t size); + int stream_recvmsg (struct stream *s, int fd, struct msghdr *, int flags, size_t size); int stream_write (struct stream *, u_char *, size_t); |