Report errors from stream read and write operations

The php_stream_read() and php_stream_write() functions now return
an ssize_t value, with negative results indicating failure. Functions
like fread() and fwrite() will return false in that case.

As a special case, EWOULDBLOCK and EAGAIN on non-blocking streams
should not be regarded as error conditions, and be reported as
successful zero-length reads/writes instead. The handling of EINTR
remains unclear and is internally inconsistent (e.g. some code-paths
will automatically retry on EINTR, while some won't).

I'm landing this now to make sure the stream wrapper ops API changes
make it into 7.4 -- however, if the user-facing changes turn out to
be problematic we have the option of clamping negative returns to
zero in php_stream_read() and php_stream_write() to restore the
old behavior in a relatively non-intrusive manner.

1 files changed, 4 insertions, 4 deletions

diff --git a/ext/openssl/xp_ssl.c b/ext/openssl/xp_ssl.c
index 3910bf815b..41f8f2308f 100644
--- a/ext/openssl/xp_ssl.c
+++ b/ext/openssl/xp_ssl.c
@@ -127,7 +127,7 @@ extern int php_openssl_get_ssl_stream_data_index();
 extern int php_openssl_get_x509_list_id(void);
 static struct timeval php_openssl_subtract_timeval(struct timeval a, struct timeval b);
 static int php_openssl_compare_timeval(struct timeval a, struct timeval b);
-static size_t php_openssl_sockop_io(int read, php_stream *stream, char *buf, size_t count);
+static ssize_t php_openssl_sockop_io(int read, php_stream *stream, char *buf, size_t count);
 
 const php_stream_ops php_openssl_socket_ops;
 
@@ -2079,13 +2079,13 @@ static int php_openssl_enable_crypto(php_stream *stream,
 }
 /* }}} */
 
-static size_t php_openssl_sockop_read(php_stream *stream, char *buf, size_t count) /* {{{ */
+static ssize_t php_openssl_sockop_read(php_stream *stream, char *buf, size_t count) /* {{{ */
 {
 	return php_openssl_sockop_io( 1, stream, buf, count );
 }
 /* }}} */
 
-static size_t php_openssl_sockop_write(php_stream *stream, const char *buf, size_t count) /* {{{ */
+static ssize_t php_openssl_sockop_write(php_stream *stream, const char *buf, size_t count) /* {{{ */
 {
 	return php_openssl_sockop_io( 0, stream, (char*)buf, count );
 }
@@ -2097,7 +2097,7 @@ static size_t php_openssl_sockop_write(php_stream *stream, const char *buf, size
  * for the duration of the operation, using select to do our waits. If we time out, or we have an error
  * report that back to PHP
  */
-static size_t php_openssl_sockop_io(int read, php_stream *stream, char *buf, size_t count) /* {{{ */
+static ssize_t php_openssl_sockop_io(int read, php_stream *stream, char *buf, size_t count) /* {{{ */
 {
 	php_openssl_netstream_data_t *sslsock = (php_openssl_netstream_data_t*)stream->abstract;