mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-24 23:32:06 +00:00
120 lines
4.6 KiB
Plaintext
120 lines
4.6 KiB
Plaintext
|
|
This file documents the librsrc.a library for accessing resource forks.
|
|
Copyright (C) 1996-1998 Robert Leslie
|
|
|
|
$Id: librsrc.txt,v 1.6 1998/09/19 05:06:32 rob Exp $
|
|
|
|
===============================================================================
|
|
|
|
Exported Data
|
|
|
|
const char *rsrc_error;
|
|
|
|
This contains a pointer to a C string describing the last resource
|
|
library error. It is generally only valid after a resource routine has
|
|
returned an error code (-1 or a NULL pointer).
|
|
|
|
In all cases when an error occurs, the global variable `errno' is also
|
|
set to an appropriate value.
|
|
|
|
Public Routines
|
|
|
|
rsrcfile *rsrc_init(void *priv, const rsrcprocs *procs);
|
|
|
|
This routine prepares an open file access path to be treated as a
|
|
Macintosh resource fork. `priv' is treated as private file access data,
|
|
and is passed transparently as the first argument to each of:
|
|
|
|
procs->seek(priv, ...);
|
|
procs->read(priv, ...);
|
|
procs->write(priv, ...);
|
|
|
|
Normally when using this library with libhfs, `priv' will be the
|
|
`hfsfile *' returned from hfs_open(), and `procs' will point to a
|
|
structure containing { hfs_seek, hfs_read, hfs_write }.
|
|
|
|
However, any suitable routines may be substituted which accept
|
|
the appropriate arguments.
|
|
|
|
Note that the file access path must already exist, and must be ready
|
|
to read and/or write resource data. When using libhfs, this means
|
|
hfs_setfork(..., 1) must be called prior to rsrc_init().
|
|
|
|
If an error occurs, this function returns -1. Otherwise it returns 0.
|
|
|
|
int rsrc_finish(rsrcfile *rfile);
|
|
|
|
Calling this routine causes the library to flush all changes to the
|
|
given resource file `rfile', and release all storage associated with it.
|
|
|
|
Note that this routine does not close the underlying file access path;
|
|
this must be done separately after calling rsrc_finish().
|
|
|
|
If an error occurs, this function returns -1. Otherwise it returns 0.
|
|
|
|
int rsrc_counttypes(rsrcfile *rfile);
|
|
|
|
This function returns the number of unique resource types in the given
|
|
resource file `rfile'.
|
|
|
|
int rsrc_count(rsrcfile *rfile, const char *type);
|
|
|
|
This function returns the number of actual resources in the given
|
|
resource file `rfile' of the given type `type', which must be a pointer
|
|
to a four-character string naming the type.
|
|
|
|
void rsrc_gettype(rsrcfile *rfile, int index, char *type);
|
|
|
|
This routine stores at `type' a four-character string (plus terminating
|
|
null) representing a resource type present in the given resource file
|
|
`rfile'. The ordinal `index' must be from 1 to the total number of
|
|
types present in the file, given by rsrc_counttypes().
|
|
|
|
If `index' is out of range, the effect of this function is undefined.
|
|
|
|
void *rsrc_get(rsrcfile *rfile, const char *type, int id);
|
|
|
|
This routine fetches an individual resource identified by the given
|
|
`type' and `id' from the resource file `rfile' and returns a pointer to
|
|
the beginning of a block containing the resource data.
|
|
|
|
The pointer returned by this function can be passed to other routines
|
|
in this library to manipulate the resource, and must finally be passed
|
|
to rsrc_release() when the resource is no longer needed.
|
|
|
|
If this function fails, a NULL pointer will be returned.
|
|
|
|
void *rsrc_getnamed(rsrcfile *rfile, const char *type, const char *name);
|
|
|
|
Like rsrc_get(), except the resource is identified by the given `name'
|
|
instead of by id.
|
|
|
|
void *rsrc_getind(rsrcfile *rfile, const char *type, int index);
|
|
|
|
Like rsrc_get(), except the resource is identified by the ordinal
|
|
`index' instead of by id. The `index' must be from 1 to the total number
|
|
of resources of type `type', given by rsrc_count().
|
|
|
|
unsigned long rsrc_size(void *rdata);
|
|
|
|
This function returns the size (in bytes) of the given resource `rdata'.
|
|
|
|
void *rsrc_resize(void *rdata, unsigned long len);
|
|
|
|
This routine changes the size of the resource data `rdata' to be `len'.
|
|
The resource data will be unchanged up to the lesser of the original
|
|
size and the new size; newly allocated space will be uninitialized.
|
|
|
|
If there is not enough memory to hold the new requested size, a NULL
|
|
pointer is returned and the original `rdata' pointer remains valid.
|
|
Otherwise, a new resource data pointer is returned and the original
|
|
becomes invalid.
|
|
|
|
void rsrc_release(void *rdata);
|
|
|
|
This function releases the resource data `rdata'. It should be called
|
|
once the data is no longer needed so the associated memory can be freed.
|
|
|
|
===============================================================================
|
|
|