Changeset 019cff6 in mainline for uspace/lib/usb/src/debug.c

Timestamp:

2011-03-04T20:11:22Z (14 years ago)

Author:

Vojtech Horky <vojtechhorky@…>

Branches:

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

Children:

ff4185e6

Parents:

3faf416c

Message:

Add buffer dumping function usb_debug_str_buffer

Example usage in USB mouse driver.

Checking etc. will be added in later revisions.

File:

• uspace/lib/usb/src/debug.c (modified) (1 diff)

uspace/lib/usb/src/debug.c

@@ -252 +252 @@
 }
 
+
+#define BUFFER_DUMP_LEN 512
+static fibril_local char buffer_dump[BUFFER_DUMP_LEN];
+
+/** Dump buffer into string.
+ *
+ * The function dumps given buffer into hexadecimal format and stores it
+ * in a static fibril local string.
+ * That means that you do not have to deallocate the string (actually, you
+ * can not do that) and you do not have to save it agains concurrent
+ * calls to it.
+ * The only limitation is that each call rewrites the buffer again.
+ * Thus, it is necessary to copy the buffer elsewhere (that includes printing
+ * to screen or writing to file).
+ * Since this function is expected to be used for debugging prints only,
+ * that is not a big limitation.
+ *
+ * @warning You cannot use this function twice in the same printf
+ * (see detailed explanation).
+ *
+ * @param buffer Buffer to be printed (can be NULL).
+ * @param size Size of the buffer in bytes (can be zero).
+ * @param dumped_size How many bytes to actually dump (zero means all).
+ * @return Dumped buffer as a static (but fibril local) string.
+ */
+const char *usb_debug_str_buffer(uint8_t *buffer, size_t size,
+    size_t dumped_size)
+{
+        if (buffer == NULL) {
+                return "(null)";
+        }
+        if (size == 0) {
+                return "(empty)";
+        }
+        if ((dumped_size == 0) || (dumped_size > size)) {
+                dumped_size = size;
+        }
+
+        char *it = buffer_dump;
+
+        size_t index = 0;
+
+        while (1) {
+                /* FIXME: add range checking of the buffer size. */
+                snprintf(it, 4, "%02X ", (int) buffer[index]);
+                it += 3;
+                index++;
+                if (index >= dumped_size) {
+                        break;
+                }
+        }
+
+        /* Remove the last space */
+        it--;
+        *it = 0;
+
+        return buffer_dump;
+}
+
+
 /**
  * @}