respect socket timeouts in generic copy path

poll() before each read in php_io_generic_copy so a blocking socket
source with a stream timeout no longer blocks forever on platforms
without a kernel offload (e.g. Haiku).

Author: devnexen

main/io/php_io.c

@@ -21,6 +21,8 @@
 #include <winsock2.h>
 #else
 #include <unistd.h>
+#include <poll.h>
+#include <errno.h>
 #endif
 
 static php_io php_io_instance = {
@@ -75,7 +77,81 @@ ssize_t php_io_generic_copy_fallback(int src_fd, int dest_fd, size_t maxlen)
 	return total_copied;
 }
 
+/* For a blocking socket source, wait until data is available (or the configured
+ * timeout elapses) before reading. Mirrors the per-platform wait_for_data
+ * helpers so the generic copy path honours stream timeouts on systems without a
+ * kernel offload (e.g. Haiku). Returns >0 ready, 0 timeout, <0 error. */
+#ifndef PHP_WIN32
+static int php_io_generic_wait_for_data(php_io_fd *fd)
+{
+	if (fd->fd_type != PHP_IO_FD_SOCKET || !fd->is_blocked) {
+		return 1;
+	}
+
+	int timeout_ms = (fd->timeout.tv_sec == -1)
+		? -1
+		: (int) (fd->timeout.tv_sec * 1000 + fd->timeout.tv_usec / 1000);
+
+	struct pollfd pfd;
+	pfd.fd = fd->fd;
+	pfd.events = POLLIN;
+
+	int ret;
+	do {
+		ret = poll(&pfd, 1, timeout_ms);
+	} while (ret == -1 && errno == EINTR);
+
+	return ret;
+}
+#else
+static int php_io_generic_wait_for_data(php_io_fd *fd)
+{
+	(void) fd;
+	return 1;
+}
+#endif
+
 ssize_t php_io_generic_copy(php_io_fd *src, php_io_fd *dest, size_t maxlen)
 {
-	return php_io_generic_copy_fallback(src->fd, dest->fd, maxlen);
+	char buf[PHP_IO_COPY_BUFSIZE];
+	ssize_t total_copied = 0;
+	size_t remaining = (maxlen == PHP_IO_COPY_ALL) ? SIZE_MAX : maxlen;
+
+	while (remaining > 0) {
+		int ready = php_io_generic_wait_for_data(src);
+		if (ready == 0) {
+			/* timeout */
+			break;
+		} else if (ready < 0) {
+			return total_copied > 0 ? total_copied : -1;
+		}
+
+		size_t to_read = (remaining < sizeof(buf)) ? remaining : sizeof(buf);
+		ssize_t bytes_read = read(src->fd, buf, to_read);
+
+		if (bytes_read < 0) {
+			return total_copied > 0 ? total_copied : -1;
+		} else if (bytes_read == 0) {
+			return total_copied;
+		}
+
+		char *writeptr = buf;
+		size_t to_write = (size_t) bytes_read;
+
+		while (to_write > 0) {
+			ssize_t bytes_written = write(dest->fd, writeptr, to_write);
+			if (bytes_written <= 0) {
+				return total_copied > 0 ? total_copied : -1;
+			}
+			total_copied += bytes_written;
+			writeptr += bytes_written;
+			to_write -= bytes_written;
+		}
+
+		if (maxlen != PHP_IO_COPY_ALL) {
+			remaining -= bytes_read;
+		}
+	}
+
+	return total_copied;
 }