diff options
| -rw-r--r-- | gdb/doc/ChangeLog | 5 | ||||
| -rw-r--r-- | gdb/doc/gdbint.texinfo | 58 |
2 files changed, 32 insertions, 31 deletions
diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog index fb75ceb..e08d7d9 100644 --- a/gdb/doc/ChangeLog +++ b/gdb/doc/ChangeLog @@ -1,3 +1,8 @@ +2004-02-26 Andrew Cagney <cagney@redhat.com> + + * gdbint.texinfo (Coding): Document use of gdbarch_obstack_zalloc + in Per-architecture module data section. + 2004-02-25 Roland McGrath <roland@redhat.com> * gdb.texinfo (General Query Packets): Document qPart:... packets. diff --git a/gdb/doc/gdbint.texinfo b/gdb/doc/gdbint.texinfo index 61d482f..1071099 100644 --- a/gdb/doc/gdbint.texinfo +++ b/gdb/doc/gdbint.texinfo @@ -4879,7 +4879,7 @@ object. A module registers one or more per-architecture data-pointers using the function @code{register_gdbarch_data}: -@deftypefun struct gdbarch_data *register_gdbarch_data (gdbarch_data_init_ftype *@var{init}, gdbarch_data_free_ftype *@var{free}) +@deftypefun struct gdbarch_data *register_gdbarch_data (gdbarch_data_init_ftype *@var{init}) The @var{init} function is used to obtain an initial value for a per-architecture data-pointer. The function is called, after the @@ -4888,10 +4888,9 @@ uninitialized (@code{NULL}) and its value has been requested via a call to @code{gdbarch_data}. A data-pointer can also be initialize explicitly using @code{set_gdbarch_data}. -The @var{free} function is called when a data-pointer needs to be -destroyed. This occurs when either the corresponding @code{struct -gdbarch} object is being destroyed or when @code{set_gdbarch_data} is -overriding a non-@code{NULL} data-pointer value. +Any memory required by the @var{init} function should be allocated +using @code{GDBARCH_OBSTACK_ZALLOC}. That memory is automatically +released when the corresponding architecture is deleted. The function @code{register_gdbarch_data} returns a @code{struct gdbarch_data} that is used to identify the data-pointer that was added @@ -4899,23 +4898,18 @@ to the module. @end deftypefun -A typical module has @code{init} and @code{free} functions of the form: +A typical module has an @code{init} function of the form: @smallexample +struct nozel @{ int total; @}; static struct gdbarch_data *nozel_handle; static void * nozel_init (struct gdbarch *gdbarch) @{ - struct nozel *data = XMALLOC (struct nozel); + struct nozel *data = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct nozel); @dots{} return data; @} -@dots{} -static void -nozel_free (struct gdbarch *gdbarch, void *data) -@{ - xfree (data); -@} @end smallexample Since uninitialized (@code{NULL}) data-pointers are initialized @@ -4930,7 +4924,7 @@ The data-pointer is registered with the call: void _initialize_nozel (void) @{ - nozel_handle = register_gdbarch_data (nozel_init, nozel_free); + nozel_handle = register_gdbarch_data (nozel_init); @dots{} @end smallexample @@ -4958,35 +4952,37 @@ nozel_total (struct gdbarch *gdbarch) It is also possible to directly initialize the data-pointer using: -@deftypefun void set_gdbarch_data (struct gdbarch *@var{gdbarch}, struct gdbarch_data *handle, void *@var{pointer}) -Update the data-pointer corresponding to @var{handle} with the value of -@var{pointer}. If the previous data-pointer value is non-NULL, then it -is freed using data-pointers @var{free} function. +@deftypefun void set_gdbarch_data (struct gdbarch *@var{gdbarch}, struct gdbarch_data *@var{handle}, void *@var{pointer}) +Set the still @code{NULL} data-pointer corresponding to @var{handle} +to the non-@code{NULL} @var{pointer} value. @end deftypefun This function is used by modules that require a mechanism for explicitly setting the per-architecture data-pointer during architecture creation: @smallexample -/* Called during architecture creation. */ -extern void -set_gdbarch_nozel (struct gdbarch *gdbarch, - int total) +/* Always return a non-NULL nozel. */ +static struct nozel * +gdbarch_nozel (struct gdbarch *gdbarch) @{ - struct nozel *data = XMALLOC (struct nozel); - @dots{} - set_gdbarch_data (gdbarch, nozel_handle, nozel); + struct nozel *nozel = gdbarch_data (gdbarch, nozel_handle); + if (nozel == NULL) + @{ + nozel = nozel_init (gdbarch); + set_gdbarch_data (gdbarch, nozel_handle, nozel); + @} + return nozel; @} @end smallexample @smallexample -/* Default, called when nozel not set by set_gdbarch_nozel(). */ -static void * -nozel_init (struct gdbarch *gdbarch) +/* Called during architecture creation. */ +extern void +set_gdbarch_nozel (struct gdbarch *gdbarch, int total) @{ - struct nozel *default_nozel = XMALLOC (struc nozel); + struct nozel *data = gdbarch_nozel (gdbarch); @dots{} - return default_nozel; + data->total = total; @} @end smallexample @@ -4994,7 +4990,7 @@ nozel_init (struct gdbarch *gdbarch) void _initialize_nozel (void) @{ - nozel_handle = register_gdbarch_data (nozel_init, NULL); + nozel_handle = register_gdbarch_data (nozel_init); @dots{} @end smallexample |