Rewrite function comments

mysys/array.c:
  Rewrite functions comments
mysys/checksum.c:
  Rewrite function comment
  Style cleanup
mysys/mulalloc.c:
  Rewrite function comment
mysys/my_chsize.c:
  Rewrite function comment
mysys/my_error.c:
  Rewrite comments
mysys/my_once.c:
  Rewrite comments
mysys/my_div.c:
  Rewrite comments
mysys/my_open.c:
  Rewrite comments

1 files changed, 108 insertions, 5 deletions

diff --git a/mysys/array.c b/mysys/array.c
index 2a0723fbd69..6d00585f24d 100644
--- a/mysys/array.c
+++ b/mysys/array.c
@@ -24,8 +24,23 @@
 #include "m_string.h"
 
 /*
-  Initiate array and alloc space for init_alloc elements. Array is usable
-  even if space allocation failed
+  Initiate dynamic array
+
+  SYNOPSIS
+    init_dynamic_array()
+      array		Pointer to an array
+      element_size	Size of element
+      init_alloc	Number of initial elements
+      alloc_increment	Increment for adding new elements
+
+  DESCRIPTION
+    init_dynamic_array() initiates array and allocate space for 
+    init_alloc eilements. 
+    Array is usable even if space allocation failed.
+
+  RETURN VALUE
+    TRUE	my_malloc_ci() failed
+    FALSE	Ok
 */
 
 my_bool init_dynamic_array(DYNAMIC_ARRAY *array, uint element_size,
@@ -52,8 +67,20 @@ my_bool init_dynamic_array(DYNAMIC_ARRAY *array, uint element_size,
     DBUG_RETURN(TRUE);
   }
   DBUG_RETURN(FALSE);
-}
+} 
 
+/*
+  Insert element at the end of array. Allocate memory if needed.
+
+  SYNOPSIS
+    insert_dynamic()
+      array
+      element
+
+  RETURN VALUE
+    TRUE	Insert failed
+    FALSE	Ok
+*/
 
 my_bool insert_dynamic(DYNAMIC_ARRAY *array, gptr element)
 {
@@ -73,7 +100,22 @@ my_bool insert_dynamic(DYNAMIC_ARRAY *array, gptr element)
 }
 
 
-	/* Alloc room for one element */
+/*
+  Alloc space for next element(s) 
+
+  SYNOPSIS
+    alloc_dynamic()
+      array
+
+  DESCRIPTION
+    alloc_dynamic() checks if there is empty space for at least
+    one element if not tries to allocate space for alloc_increment
+    elements at the end of array.
+
+  RETURN VALUE
+    pointer	Pointer to empty space for element
+    0		Error
+*/
 
 byte *alloc_dynamic(DYNAMIC_ARRAY *array)
 {
@@ -92,7 +134,17 @@ byte *alloc_dynamic(DYNAMIC_ARRAY *array)
 }
 
 
-	/* remove last element from array and return it */
+/*
+  Pop last element from array.
+
+  SYNOPSIS
+    pop_dynamic()
+      array
+  
+  RETURN VALUE    
+    pointer	Ok
+    0		Array is empty
+*/
 
 byte *pop_dynamic(DYNAMIC_ARRAY *array)
 {
@@ -101,6 +153,23 @@ byte *pop_dynamic(DYNAMIC_ARRAY *array)
   return 0;
 }
 
+/*
+  Replace elemnent in array with given element and index
+
+  SYNOPSIS
+    set_dynamic()
+      array
+      element	Element to be inserted
+      idx	Index where element is to be inserted
+
+  DESCRIPTION
+    set_dynamic() replaces element in array. 
+    If idx > max_element insert new element. Allocate memory if needed. 
+ 
+  RETURN VALUE
+    TRUE	Idx was out of range and allocation of new memory failed
+    FALSE	Ok
+*/
 
 my_bool set_dynamic(DYNAMIC_ARRAY *array, gptr element, uint idx)
 {
@@ -128,6 +197,15 @@ my_bool set_dynamic(DYNAMIC_ARRAY *array, gptr element, uint idx)
   return FALSE;
 }
 
+/*
+  Get an element from array by given index
+
+  SYNOPSIS
+    get_dynamic()
+      array	
+      gptr	Element to be returned. If idx > elements contain zeroes.
+      idx	Index of element wanted. 
+*/
 
 void get_dynamic(DYNAMIC_ARRAY *array, gptr element, uint idx)
 {
@@ -143,6 +221,14 @@ void get_dynamic(DYNAMIC_ARRAY *array, gptr element, uint idx)
 }
 
 
+/*
+  Empty array by freeing all memory
+
+  SYNOPSIS
+    delete_dynamic()
+      array	Array to be deleted
+*/
+
 void delete_dynamic(DYNAMIC_ARRAY *array)
 {
   if (array->buffer)
@@ -153,6 +239,14 @@ void delete_dynamic(DYNAMIC_ARRAY *array)
   }
 }
 
+/*
+  Delete element by given index
+
+  SYNOPSIS
+    delete_dynamic_element()
+      array
+      idx	Index of element to be deleted
+*/
 
 void delete_dynamic_element(DYNAMIC_ARRAY *array, uint idx)
 {
@@ -163,6 +257,15 @@ void delete_dynamic_element(DYNAMIC_ARRAY *array, uint idx)
 }
 
 
+/*
+  Free unused memory
+
+  SYNOPSIS
+    freeze_size()
+      array	Array to be freed
+
+*/
+
 void freeze_size(DYNAMIC_ARRAY *array)
 {
   uint elements=max(array->elements,1);