Changeset ba519f7 in mainline for uspace/lib/c/generic/device/char.c

Timestamp:

2010-12-02T17:21:30Z (13 years ago)

Author:

Martin Sucha <sucha14@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

3bd76491

Parents:

8ad673a (diff), 41a7f62 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge from mainline

File:

• uspace/lib/c/generic/device/char.c (modified) (3 diffs)

uspace/lib/c/generic/device/char.c

@@ -26 +26 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
- 
+
  /** @addtogroup libc
  * @{
@@ -40 +40 @@
 #include <stdio.h>
 
-/** Read to or write from the device using its character interface.
- * 
- * Helper function.
- * 
- * @param dev_phone phone to the device.
- * @param buf the buffer for the data read from or written to the device.
- * @param len the maximum length of the data to be read or written.
- * @param read read from the device if true, write to it otherwise.
- * 
- * @return non-negative number of bytes actually read from or written to the device on success,
- * negative error number otherwise.
- * 
+/** Read to or write from device.
+ *
+ * Helper function to read to or write from a device
+ * using its character interface.
+ *
+ * @param dev_phone Phone to the device.
+ * @param buf       Buffer for the data read
+ *                  from or written to the device.
+ * @param len       Maximum length of the data to be
+ *                  read or written.
+ * @param read      Read from the device if true,
+ *                  write to it otherwise.
+ *
+ * @return Non-negative number of bytes actually read
+ *         from or written to the device on success,
+ *         negative error number otherwise.
+ *
  */
-static int rw_dev(int dev_phone, void *buf, size_t len, bool read) 
+static ssize_t rw_dev(int dev_phone, void *buf, size_t len, bool read)
 {
-        ipc_call_t answer;
-        
         async_serialize_start();
         
+        ipc_call_t answer;
         aid_t req;
         int ret;
         
         if (read) {
-                req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE), CHAR_READ_DEV, &answer);
-                ret = async_data_read_start(dev_phone, buf, len);               
+                req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE),
+                    CHAR_READ_DEV, &answer);
+                ret = async_data_read_start(dev_phone, buf, len);
         } else {
-                req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE), CHAR_WRITE_DEV, &answer);
+                req = async_send_1(dev_phone, DEV_IFACE_ID(CHAR_DEV_IFACE),
+                    CHAR_WRITE_DEV, &answer);
                 ret = async_data_write_start(dev_phone, buf, len);
         }
         
         ipcarg_t rc;
-        if (ret != EOK) {               
+        if (ret != EOK) {
                 async_wait_for(req, &rc);
                 async_serialize_end();
-                if (rc == EOK) {
-                        return ret;
-                }
-                else {
-                        return (int) rc;
-                }
+                if (rc == EOK)
+                        return (ssize_t) ret;
+                        
+                return (ssize_t) rc;
         }
         
@@ -85 +89 @@
         async_serialize_end();
         
-        ret = (int)rc;
-        if (EOK != ret) {
-                return ret;
-        }
+        ret = (int) rc;
+        if (ret != EOK)
+                return (ssize_t) ret;
         
-        return IPC_GET_ARG1(answer);    
+        return (ssize_t) IPC_GET_ARG1(answer);
 }
 
-/** Read from the device using its character interface.
- * 
- * @param dev_phone phone to the device.
- * @param buf the output buffer for the data read from the device.
- * @param len the maximum length of the data to be read.
- * 
- * @return non-negative number of bytes actually read from the device on success, negative error number otherwise.
+/** Read from device using its character interface.
+ *
+ * @param dev_phone Phone to the device.
+ * @param buf       Output buffer for the data
+ *                  read from the device.
+ * @param len       Maximum length of the data to be read.
+ *
+ * @return Non-negative number of bytes actually read
+ *         from the device on success, negative error
+ *         number otherwise.
+ *
  */
-int read_dev(int dev_phone, void *buf, size_t len)
-{       
+ssize_t read_dev(int dev_phone, void *buf, size_t len)
+{
         return rw_dev(dev_phone, buf, len, true);
 }
 
-/** Write to the device using its character interface.
- * 
- * @param dev_phone phone to the device.
- * @param buf the input buffer containg the data to be written to the device.
- * @param len the maximum length of the data to be written.
- * 
- * @return non-negative number of bytes actually written to the device on success, negative error number otherwise.
+/** Write to device using its character interface.
+ *
+ * @param dev_phone Phone to the device.
+ * @param buf       Input buffer containg the data
+ *                  to be written to the device.
+ * @param len       Maximum length of the data to be written.
+ *
+ * @return Non-negative number of bytes actually written
+ *         to the device on success, negative error number
+ *         otherwise.
+ *
  */
-int write_dev(int dev_phone, void *buf, size_t len)
+ssize_t write_dev(int dev_phone, void *buf, size_t len)
 {
         return rw_dev(dev_phone, buf, len, false);
 }
 
-  
- /** @}
+/** @}
  */