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|
#! /usr/bin/env python3
'''
Python version of the C API in psi/iapi.h.
Overview:
Implemented using Python's ctypes module.
All functions have the same name as the C function that they wrap.
Functions raise a GSError exception if the underlying function returned a
negative error code.
Functions that don't have out-params return None. Out-params are returned
directly (using tuples if there are more than one).
See examples.py for sample usage.
Example usage:
On Linux/OpenBSD/MacOS:
Build the ghostscript shared library:
make sodebug
Run gsapi.py as a test script:
GSAPI_LIBDIR=sodebugbin ./demos/python/gsapi.py
On Windows:
Build ghostscript dll, for example:
devenv.com windows/GhostPDL.sln /Build Debug /Project ghostscript
Run gsapi.py as a test script in a cmd.exe window:
set GSAPI_LIBDIR=debugbin&& python ./demos/python/gsapi.py
Run gsapi.py as a test script in a PowerShell window:
cmd /C "set GSAPI_LIBDIR=debugbin&& python ./demos/python/gsapi.py"
Specifying the Ghostscript shared library:
Two environmental variables can be used to specify where to find the
Ghostscript shared library.
GSAPI_LIB sets the exact path of the ghostscript shared library, else
GSAPI_LIBDIR sets the directory containing the ghostscript shared
library. If neither is defined we will use the OS's default location(s) for
shared libraries.
If GSAPI_LIB is not defined, the leafname of the shared library is inferred
from the OS type - libgs.so on Unix, libgs.dylib on MacOS, gsdll64.dll on
Windows 64.
Requirements:
Should work on python-2.5+ and python-3.0+, but this might change in
future.
Limitations as of 2020-07-21:
Only very limited testing on has been done.
Tested on Linux, OpenBSD and Windows.
Only tested with python-3.7 and 2.7.
We don't provide gsapi_add_fs() or gsapi_remove_fs().
We only provide display_callback V2, without V3's
display_adjust_band_height and display_rectangle_request.
'''
import ctypes
import os
import platform
import sys
_lib = os.environ.get('GSAPI_LIB')
if not _lib:
if platform.system() in ('Linux', 'OpenBSD'):
_lib = 'libgs.so'
elif platform.system() == 'Darwin':
_lib = 'libgs.dylib'
elif platform.system() == 'Windows':
if sys.maxsize == 2**31 - 1:
_lib = 'gsdll32.dll'
elif sys.maxsize == 2**63 - 1:
_lib = 'gsdll64.dll'
else:
raise Exception('Unrecognised sys.maxsize=0x%x' % sys.maxsize)
else:
raise Exception('Unrecognised platform.system()=%s' % platform.system())
_libdir = os.environ.get('GSAPI_LIBDIR')
if _libdir:
_lib = os.path.join(_libdir, _lib)
try:
_libgs = ctypes.CDLL(_lib)
except Exception as e:
print('gsapi.py: Failed to load Ghostscript library "%s".' % _lib)
raise
class GSError(Exception):
'''
Exception type for all errors from underlying C library.
'''
def __init__(self, gs_error):
self.gs_error = gs_error
def __str__(self):
return 'Ghostscript exception %i: %s' % (
self.gs_error,
_gs_error_text(self.gs_error),
)
class gsapi_revision_t:
def __init__(self, product, copyright, revision, revisiondate):
self.product = product
self.copyright = copyright
self.revision = revision
self.revisiondate = revisiondate
def __str__(self):
return 'product=%r copyright=%r revision=%r revisiondate=%r' % (
self.product,
self.copyright,
self.revision,
self.revisiondate,
)
def gsapi_revision():
'''
Returns a gsapi_revision_t.
'''
# [unicode: we assume that underlying gsapi_revision() returns utf-8
# strings.]
_r = _gsapi_revision_t()
e = _libgs.gsapi_revision(ctypes.byref(_r), ctypes.sizeof(_r))
if e < 0:
raise GSError(e)
r = gsapi_revision_t(
_r.product.decode('utf-8'),
_r.copyright.decode('utf-8'),
_r.revision,
_r.revisiondate,
)
return r
def gsapi_new_instance(caller_handle=None):
'''
Returns an <instance> to be used with other gsapi_*() functions.
caller_handle:
Typically unused, but is passed to callbacks e.g. via
gsapi_set_stdio(). Must be convertable to a C void*, so None or an
integer is ok but other types such as strings will fail.
'''
instance = ctypes.c_void_p()
e = _libgs.gsapi_new_instance(
ctypes.byref(instance),
ctypes.c_void_p(caller_handle),
)
if e < 0:
raise GSError(e)
return instance
def gsapi_delete_instance(instance):
e = _libgs.gsapi_delete_instance(instance)
if e < 0:
raise GSError(e)
def gsapi_set_stdio(instance, stdin_fn, stdout_fn, stderr_fn):
'''
stdin_fn:
If not None, will be called with (caller_handle, text, len_):
caller_handle:
As passed originally to gsapi_new_instance().
text:
A ctypes.LP_c_char of length <len_>.
[todo: wrap this to be easier to use from Python?]
stdout_fn and stderr_fn:
If not None, called with (caller_handle, text):
caller_handle:
As passed originally to gsapi_new_instance().
text:
A Python bytes object.
Should return the number of bytes of <text> that they handled; for
convenience None is converted to len(text).
'''
# [unicode: we do not do any encoding or decoding; stdin_fn should encode
# and stdout_fn and stderr_fn should decode. ]
def make_out(fn):
if not fn:
return None
def out(caller_handle, text, len_):
text2 = text[:len_] # converts from ctypes.LP_c_char to bytes.
ret = fn(caller_handle, text2)
if ret is None:
return len_
return ret
return _stdio_fn(out)
def make_in(fn):
if not fn:
return None
return _stdio_fn(fn)
stdout_fn2 = make_out(stdout_fn)
stderr_fn2 = make_out(stderr_fn)
stdin_fn2 = make_in(stdin_fn)
e = _libgs.gsapi_set_stdio(instance, stdout_fn2, stdout_fn2, stdout_fn2)
if e < 0:
raise GSError(e)
# Need to keep references to call-back functions.
global _gsapi_set_stdio_refs
_gsapi_set_stdio_refs = stdin_fn2, stdout_fn2, stderr_fn2
def gsapi_set_poll(instance, poll_fn):
'''
poll_fn:
Will be called with (caller_handle) where <caller_handle> is as passed
to gsapi_new_instance().
Not tested.
'''
poll_fn2 = _poll_fn(poll_fn)
e = _libgs.gsapi_set_poll(instance, poll_fn2)
if e < 0:
raise GSError(e)
global _gsapi_set_poll_refs
_gsapi_set_poll_refs = poll_fn2
class display_callback:
def __init__(self,
version_major = 0,
version_minor = 0,
display_open = 0,
display_preclose = 0,
display_close = 0,
display_presize = 0,
display_size = 0,
display_sync = 0,
display_page = 0,
display_update = 0,
display_memalloc = 0,
display_memfree = 0,
display_separation = 0,
display_adjust_band_height = 0,
):
self.version_major = version_major
self.version_minor = version_minor
self.display_open = display_open
self.display_preclose = display_preclose
self.display_close = display_close
self.display_presize = display_presize
self.display_size = display_size
self.display_sync = display_sync
self.display_page = display_page
self.display_update = display_update
self.display_memalloc = display_memalloc
self.display_memfree = display_memfree
self.display_separation = display_separation
self.display_adjust_band_height = display_adjust_band_height
def gsapi_set_display_callback(instance, callback):
'''
callback:
Must be a <display_callback> instance.
'''
assert isinstance(callback, display_callback)
callback2 = _display_callback()
callback2.size = ctypes.sizeof(callback2)
# Copy from <callback> into <callback2>.
for name, type_ in _display_callback._fields_:
if name == 'size':
continue
value = getattr(callback, name)
value2 = type_(value)
setattr(callback2, name, value2)
e = _libgs.gsapi_set_display_callback(instance, ctypes.byref(callback2))
if e < 0:
raise GSError(e)
# Ensure that we keep references to callbacks.
global _gsapi_set_display_callback_refs
_gsapi_set_display_callback_refs = callback2
def gsapi_set_default_device_list(instance, list_):
'''
list_:
Must be a string.
'''
# [unicode: we assume that underlying gsapi_set_default_device_list() is
# expecting list_ to be in utf-8 encoding.]
assert isinstance(list_, str)
list_2 = list_.encode('utf-8')
e = _libgs.gsapi_set_default_device_list(instance, list_2, len(list_))
if e < 0:
raise GSError(e)
def gsapi_get_default_device_list(instance):
'''
Returns a string.
'''
# [unicode: we assume underlying gsapi_get_default_device_list() returns
# strings encoded as latin-1.]
list_ = ctypes.POINTER(ctypes.c_char)()
len_ = ctypes.c_int()
e = _libgs.gsapi_get_default_device_list(
instance,
ctypes.byref(list_),
ctypes.byref(len_),
)
if e < 0:
raise GSError(e)
return list_[:len_.value].decode('latin-1')
GS_ARG_ENCODING_LOCAL = 0
GS_ARG_ENCODING_UTF8 = 1
GS_ARG_ENCODING_UTF16LE = 2
def gsapi_set_arg_encoding(instance, encoding):
'''
encoding:
Must be one of:
GS_ARG_ENCODING_LOCAL
GS_ARG_ENCODING_UTF8
GS_ARG_ENCODING_UTF16LE
'''
assert encoding in (
GS_ARG_ENCODING_LOCAL,
GS_ARG_ENCODING_UTF8,
GS_ARG_ENCODING_UTF16LE,
)
global _encoding
e = _libgs.gsapi_set_arg_encoding(instance, encoding)
if e < 0:
raise GSError(e)
if encoding == GS_ARG_ENCODING_LOCAL:
# This is probably wrong on Windows.
_encoding = 'utf-8'
elif encoding == GS_ARG_ENCODING_UTF8:
_encoding = 'utf-8'
elif encoding == GS_ARG_ENCODING_UTF16LE:
_encoding = 'utf-16-le'
def gsapi_init_with_args(instance, args):
'''
args:
A list/tuple of strings.
'''
# [unicode: we assume that underlying gsapi_init_with_args()
# expects strings in args[] to be encoded in encoding set by
# gsapi_set_arg_encoding().]
# Create copy of args in format expected by C.
argc = len(args)
argv = (_pchar * (argc + 1))()
for i, arg in enumerate(args):
enc_arg = arg.encode(_encoding)
argv[i] = ctypes.create_string_buffer(enc_arg)
argv[argc] = None
e = _libgs.gsapi_init_with_args(instance, argc, argv)
if e < 0:
raise GSError(e)
def gsapi_run_string_begin(instance, user_errors=0):
'''
Returns <exit_code>.
'''
pexit_code = ctypes.c_int()
e = _libgs.gsapi_run_string_begin(instance, user_errors, ctypes.byref(pexit_code))
if e < 0:
raise GSError(e)
return pexit_code.value
def gsapi_run_string_continue(instance, str_, user_errors=0):
'''
<str_> should be either a python string or a bytes object. If the former,
it is converted into a bytes object using utf-8 encoding.
We don't raise exception for gs_error_NeedInput.
Returns <exit_code>.
'''
if isinstance(str_, str):
str_ = str_.encode('utf-8')
assert isinstance(str_, bytes)
pexit_code = ctypes.c_int()
e = _libgs.gsapi_run_string_continue(
instance,
str_,
len(str_),
user_errors,
ctypes.byref(pexit_code),
)
if e == gs_error_NeedInput.num:
# This is normal, so we don't raise.
pass
elif e < 0:
raise GSError(e)
return pexit_code.value
def gsapi_run_string_end(instance, user_errors=0):
'''
Returns <exit_code>.
'''
pexit_code = ctypes.c_int()
e = _libgs.gsapi_run_string_end(
instance,
user_errors,
ctypes.byref(pexit_code),
)
if e < 0:
raise GSError(e)
return pexit_code.value
def gsapi_run_string_with_length(instance, str_, length, user_errors=0):
'''
<str_> should be either a python string or a bytes object. If the former,
it is converted into a bytes object using utf-8 encoding.
Returns <exit_code>.
'''
return gsapi_run_string(instance, str_[:length], user_errors=0)
def gsapi_run_string(instance, str_, user_errors=0):
'''
<str_> should be either a python string or a bytes object. If the former,
it is converted into a bytes object using utf-8 encoding.
Returns <exit_code>.
'''
if isinstance(str_, str):
str_ = str_.encode('utf-8')
assert isinstance(str_, bytes)
pexit_code = ctypes.c_int()
# We use gsapi_run_string_with_length() because str_ might contain zeros.
e = _libgs.gsapi_run_string_with_length(
instance,
str_,
len(str_),
user_errors,
ctypes.byref(pexit_code),
)
if e < 0:
raise GSError(e)
return pexit_code.value
def gsapi_run_file(instance, filename, user_errors=0):
'''
Returns <exit_code>.
'''
# [unicode: we assume that underlying gsapi_run_file() expects <filename>
# to be encoded in encoding set by gsapi_set_arg_encoding().]
pexit_code = ctypes.c_int()
filename2 = filename.encode(_encoding)
e = _libgs.gsapi_run_file(instance, filename2, user_errors, ctypes.byref(pexit_code))
if e < 0:
raise GSError(e)
return pexit_code.value
def gsapi_exit(instance):
e = _libgs.gsapi_exit(instance)
if e < 0:
raise GSError(e)
gs_spt_invalid = -1
gs_spt_null = 0 # void * is NULL.
gs_spt_bool = 1 # void * is NULL (false) or non-NULL (true).
gs_spt_int = 2 # void * is a pointer to an int.
gs_spt_float = 3 # void * is a float *.
gs_spt_name = 4 # void * is a char *.
gs_spt_string = 5 # void * is a char *.
gs_spt_long = 6 # void * is a long *.
gs_spt_i64 = 7 # void * is an int64_t *.
gs_spt_size_t = 8 # void * is a size_t *.
gs_spt_parsed = 9 # void * is a pointer to a char * to be parsed.
gs_spt__end = 10
gs_spt_more_to_come = 2**31
def gsapi_set_param(instance, param, value, type_=None):
'''
We behave much like the underlying gsapi_set_param() C function, except
that we also support automatic inference of type type_ arg by looking at
the type of <value>.
param:
Name of parameter, either a bytes or a str; if str it is encoded using
latin-1.
value:
A bool, int, float, bytes or str. If str, it is encoded into a bytes
using utf-8.
If <type_> is not None, <value> must be convertible to the Python type
implied by <type_>:
type_ Python type(s)
-----------------------------------------
gs_spt_null [Ignored]
gs_spt_bool bool
gs_spt_int int
gs_spt_float float
gs_spt_name [Error]
gs_spt_string (bytes, str)
gs_spt_long int
gs_spt_i64 int
gs_spt_size_t int
gs_spt_parsed (bytes, str)
We raise an exception if <type_> is an integer type and <value> is
outside its range.
type_:
If None, we choose something suitable for type of <value>:
Python type of <value> type_
-----------------------------
bool gs_spt_bool
int gs_spt_i64
float gs_spt_float
bytes gs_spt_parsed
str gs_spt_parsed (encoded with utf-8)
If <value> is None, we use gs_spt_null.
Otherwise type_ must be a gs_spt_* except for gs_spt_invalid and
gs_spt_name (we don't allow psapi_spt_name because the underlying C
does not copy the string, so cannot be safely used from Python).
'''
# [unicode: we assume that underlying gsapi_set_param() expects <param> and
# string <value> to be encoded as latin-1.]
if isinstance(param, str):
param = param.encode('latin-1')
assert isinstance(param, bytes)
if type_ is None:
# Choose a gs_spt_* that matches the Python type of <value>.
if value is None:
type_ = gs_spt_null
elif isinstance(value, bool):
type_ = gs_spt_bool
elif isinstance(value, int):
type_ = gs_spt_i64
elif isinstance(value, float):
type_ = gs_spt_float
elif isinstance(value, (bytes, str)):
type_ = gs_spt_parsed
else:
raise Exception('Unrecognised Python type (must be bool, int, float, bytes or str): %s' % type(value))
# Make a <value2> suitable for the underlying C gsapi_set_param() function.
#
if type_ == gs_spt_null:
# special-case, we pass value2=None.
value2 = None
elif type_ == gs_spt_name:
# Unsupported.
raise Exception('gs_spt_name is not supported from Python')
elif type_ in (gs_spt_string, gs_spt_parsed):
# String.
value2 = value
if isinstance(value2, str):
value2 = value2.encode('utf-8')
assert isinstance(value2, bytes)
else:
# Bool/int/float.
type2 = None
if type_ == gs_spt_bool:
type2 = ctypes.c_int
elif type_ == gs_spt_int:
type2 = ctypes.c_int
elif type_ == gs_spt_float:
type2 = ctypes.c_float
elif type_ == gs_spt_long:
type2 = ctypes.c_long
elif type_ == gs_spt_i64:
type2 = ctypes.c_int64
elif type_ == gs_spt_size_t:
type2 = ctypes.c_size_t
else:
assert 0, 'unrecognised gs_spt_ value: %s' % type_
value2 = type2(value)
if type_ not in (gs_spt_float, gs_spt_bool):
# Check for out-of-range integers.
if value2.value != value:
raise Exception('Value %s => %s is out of range for type %s (%s)' % (
value, value2.value, type_, type2))
value2 = ctypes.byref(value2)
e = _libgs.gsapi_set_param(instance, param, value2, type_)
if e < 0:
raise GSError(e)
def gsapi_get_param(instance, param, type_=None, encoding=None):
'''
Returns value of specified parameter, or None if parameter type is
gs_spt_null.
param:
Name of parameter, either a bytes or str; if a str it is encoded using
latin-1.
type:
A gs_spt_* constant or None. If None we try each gs_spt_* until one
succeeds; if none succeeds we raise the last error.
encoding:
Only affects string values. If None we return a bytes object, otherwise
it should be the encoding to use to decode into a string, e.g. 'utf-8'.
'''
# [unicode: we assume that underlying gsapi_get_param() expects <param> to
# be encoded as latin-1.]
#
param2 = param
if isinstance(param2, str):
param2 = param2.encode('latin-1')
assert isinstance(param2, bytes)
def _get_simple(value_type):
value = value_type()
e = _libgs.gsapi_get_param(instance, param2, ctypes.byref(value), type_)
if e < 0:
raise GSError(e)
return value.value
if type_ is None:
# Try each type until one succeeds. We raise the last error if no type
# works.
for type_ in range(0, gs_spt__end):
try:
ret = gsapi_get_param(instance, param2, type_, encoding)
return ret
except GSError as e:
last_error = e
raise last_error
elif type_ == gs_spt_null:
e = _libgs.gsapi_get_param(instance, param2, None, type_)
if e < 0:
raise GSError(e)
return None
elif type_ == gs_spt_bool:
ret = _get_simple(ctypes.c_int)
return ret != 0
elif type_ == gs_spt_int:
return _get_simple(ctypes.c_int)
elif type_ == gs_spt_float:
return _get_simple(ctypes.c_float)
elif type_ == gs_spt_long:
return _get_simple(ctypes.c_long)
elif type_ == gs_spt_i64:
return _get_simple(ctypes.c_int64)
elif type_ == gs_spt_size_t:
return _get_simple(ctypes.c_size_t)
elif type_ in (gs_spt_name, gs_spt_string, gs_spt_parsed):
# Value is a string, so get required buffer size.
e = _libgs.gsapi_get_param(instance, param2, None, type_)
if e < 0:
raise GSError(e)
value = ctypes.create_string_buffer(e)
e = _libgs.gsapi_get_param(instance, param2, ctypes.byref(value), type_)
if e < 0:
raise GSError(e)
ret = value.value
if encoding:
ret = ret.decode(encoding)
return ret
else:
raise Exception('Unrecognised type_=%s' % type_)
def gsapi_enumerate_params(instance):
'''
Yields (key, value) for each param. <key> is decoded as latin-1.
'''
# [unicode: we assume that param names are encoded as latin-1.]
iterator = ctypes.c_void_p()
key = ctypes.c_char_p()
type_ = ctypes.c_int()
while 1:
e = _libgs.gsapi_enumerate_params(
instance,
ctypes.byref(iterator),
ctypes.byref(key),
ctypes.byref(type_),
)
if e == 1:
break
if e:
raise GSError(e)
yield key.value.decode('latin-1'), type_.value
GS_PERMIT_FILE_READING = 0
GS_PERMIT_FILE_WRITING = 1
GS_PERMIT_FILE_CONTROL = 2
def gsapi_add_control_path(instance, type_, path):
# [unicode: we assume that underlying gsapi_add_control_path() expects
# <path> to be encoded in encoding set by gsapi_set_arg_encoding().]
path2 = path.encode(_encoding)
e = _libgs.gsapi_add_control_path(instance, type_, path2)
if e < 0:
raise GSError(e)
def gsapi_remove_control_path(instance, type_, path):
# [unicode: we assume that underlying gsapi_remove_control_path() expects
# <path> to be encoded in encoding set by gsapi_set_arg_encoding().]
path2 = path.encode(_encoding)
e = _libgs.gsapi_remove_control_path(instance, type_, path2)
if e < 0:
raise GSError(e)
def gsapi_purge_control_paths(instance, type_):
e = _libgs.gsapi_purge_control_paths(instance, type_)
if e < 0:
raise GSError(e)
def gsapi_activate_path_control(instance, enable):
e = _libgs.gsapi_activate_path_control(instance, enable)
if e < 0:
raise GSError(e)
def gsapi_is_path_control_active(instance):
e = _libgs.gsapi_is_path_control_active(instance)
if e < 0:
raise GSError(e)
# Implementation details.
#
_Error_num_to_error = dict()
class _Error:
def __init__(self, num, desc):
self.num = num
self.desc = desc
_Error_num_to_error[self.num] = self
gs_error_ok = _Error( 0, 'ok')
gs_error_unknownerror = _Error( -1, 'unknown error')
gs_error_dictfull = _Error( -2, 'dict full')
gs_error_dictstackoverflow = _Error( -3, 'dict stack overflow')
gs_error_dictstackunderflow = _Error( -4, 'dict stack underflow')
gs_error_execstackoverflow = _Error( -5, 'exec stack overflow')
gs_error_interrupt = _Error( -6, 'interrupt')
gs_error_invalidaccess = _Error( -7, 'invalid access')
gs_error_invalidexit = _Error( -8, 'invalid exit')
gs_error_invalidfileaccess = _Error( -9, 'invalid fileaccess')
gs_error_invalidfont = _Error( -10, 'invalid font')
gs_error_invalidrestore = _Error( -11, 'invalid restore')
gs_error_ioerror = _Error( -12, 'ioerror')
gs_error_limitcheck = _Error( -13, 'limit check')
gs_error_nocurrentpoint = _Error( -14, 'no current point')
gs_error_rangecheck = _Error( -15, 'range check')
gs_error_stackoverflow = _Error( -16, 'stack overflow')
gs_error_stackunderflow = _Error( -17, 'stack underflow')
gs_error_syntaxerror = _Error( -18, 'syntax error')
gs_error_timeout = _Error( -19, 'timeout')
gs_error_typecheck = _Error( -20, 'type check')
gs_error_undefined = _Error( -21, 'undefined')
gs_error_undefinedfilename = _Error( -22, 'undefined filename')
gs_error_undefinedresult = _Error( -23, 'undefined result')
gs_error_unmatchedmark = _Error( -24, 'unmatched mark')
gs_error_VMerror = _Error( -25, 'VMerror')
gs_error_configurationerror = _Error( -26, 'configuration error')
gs_error_undefinedresource = _Error( -27, 'undefined resource')
gs_error_unregistered = _Error( -28, 'unregistered')
gs_error_invalidcontext = _Error( -29, 'invalid context')
gs_error_invalidid = _Error( -30, 'invalid id')
gs_error_hit_detected = _Error( -99, 'hit detected')
gs_error_Fatal = _Error(-100, 'Fatal')
gs_error_Quit = _Error(-101, 'Quit')
gs_error_InterpreterExit = _Error(-102, 'Interpreter Exit')
gs_error_Remap_Color = _Error(-103, 'Remap Color')
gs_error_ExecStackUnderflow = _Error(-104, 'Exec Stack Underflow')
gs_error_VMreclaim = _Error(-105, 'VM reclaim')
gs_error_NeedInput = _Error(-106, 'Need Input')
gs_error_NeedFile = _Error(-107, 'Need File')
gs_error_Info = _Error(-110, 'Info')
gs_error_handled = _Error(-111, 'handled')
def _gs_error_text(gs_error):
'''
Returns text description of <gs_error>. See base/gserrors.h.
'''
e = _Error_num_to_error.get(gs_error)
if e:
return e.desc
return 'no error'
# The encoding that we use when passing strings to the underlying gsapi_*() C
# functions. Changed by gsapi_set_arg_encoding().
#
# This default is probably incorrect on Windows.
#
_encoding = 'utf-8'
class _gsapi_revision_t(ctypes.Structure):
_fields_ = [
('product', ctypes.c_char_p),
('copyright', ctypes.c_char_p),
('revision', ctypes.c_long),
('revisiondate', ctypes.c_long),
]
_stdio_fn = ctypes.CFUNCTYPE(
ctypes.c_int, # return
ctypes.c_void_p, # caller_handle
ctypes.POINTER(ctypes.c_char), # str
ctypes.c_int, # len
)
_gsapi_set_stdio_refs = None
# ctypes representation of int (*poll_fn)(void* caller_handle).
#
_poll_fn = ctypes.CFUNCTYPE(
ctypes.c_int, # return
ctypes.c_void_p, # caller_handle
)
_gsapi_set_poll_refs = None
# ctypes representation of display_callback.
#
class _display_callback(ctypes.Structure):
_fields_ = [
('size', ctypes.c_int),
('version_major', ctypes.c_int),
('version_minor', ctypes.c_int),
('display_open',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
)),
('display_preclose',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
)),
('display_close',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
)),
('display_presize',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_int, # width
ctypes.c_int, # height
ctypes.c_int, # raster
ctypes.c_uint, # format
)),
('display_size',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_int, # width
ctypes.c_int, # height
ctypes.c_int, # raster
ctypes.c_uint, # format
ctypes.c_char_p, # pimage
)),
('display_sync',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
)),
('display_page',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_int, # copies
ctypes.c_int, # flush
)),
('display_update',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_int, # x
ctypes.c_int, # y
ctypes.c_int, # w
ctypes.c_int, # h
)),
('display_memalloc',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_ulong, # size
)),
('display_memfree',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_void_p, # mem
)),
('display_separation',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_void_p, # handle
ctypes.c_void_p, # device
ctypes.c_int, # component
ctypes.c_char_p, # component_name
ctypes.c_ushort, # c
ctypes.c_ushort, # m
ctypes.c_ushort, # y
ctypes.c_ushort, # k
)),
]
_libgs.gsapi_set_display_callback.argtypes = (
ctypes.c_void_p, # instance
ctypes.POINTER(_display_callback), # callback
)
_gsapi_set_display_callback_refs = None
# See:
#
# https://stackoverflow.com/questions/58598012/ctypes-errors-with-argv
#
_pchar = ctypes.POINTER(ctypes.c_char)
_ppchar = ctypes.POINTER(_pchar)
_libgs.gsapi_init_with_args.argtypes = (
ctypes.c_void_p, # instance
ctypes.c_int, # argc
_ppchar, # argv
)
if 0:
# Not implemented yet:
# gsapi_add_fs()
# gsapi_remove_fs()
#
class gsapi_fs_t(ctypes.Structure): # lgtm [py/unreachable-statement]
_fields_ = [
('open_file',
ctypes.CFUNCTYPE(ctypes.c_int,
ctypes.c_pvoid, # const gs_memory_t *mem
ctypes.c_pvoid, # secret
ctypes.c_char_p, # fname
ctypes.c_char_p, # mode
)),
]
if __name__ == '__main__':
# test
#
print('Running some very simple and incomplete tests...')
print('libgs: %s' % _libgs)
revision = gsapi_revision()
print('libgs.gsapi_revision() ok: %s' % revision)
instance = gsapi_new_instance()
print('gsapi_new_instance() ok: %s' % instance)
gsapi_set_arg_encoding(instance, GS_ARG_ENCODING_UTF8)
print('gsapi_set_arg_encoding() ok.')
def stdout_fn(caller_handle, bytes_):
sys.stdout.write(bytes_.decode('latin-1'))
gsapi_set_stdio(instance, None, stdout_fn, None)
print('gsapi_set_stdio() ok.')
d = display_callback()
gsapi_set_display_callback(instance, d)
print('gsapi_set_display_callback() ok.')
gsapi_set_default_device_list(instance, 'bmp256 bmp32b bmpgray bmpmono bmpsep1 bmpsep8 ccr cdeskjet cdj1600 cdj500')
print('gsapi_set_default_device_list() ok.')
l = gsapi_get_default_device_list(instance)
print('gsapi_get_default_device_list() ok: l=%s' % l)
gsapi_init_with_args(instance, ['gs',])
print('gsapi_init_with_args() ok')
gsapi_set_param(instance, "foo", 100, gs_spt_i64)
try:
gsapi_get_param(instance, "foo", gs_spt_i64)
except GSError as e:
assert e.gs_error == gs_error_undefined.num, e.gs_error
else:
assert 0, 'expected gsapi_get_param() to fail'
# Check specifying invalid type raises exception.
try:
gsapi_get_param(instance, None, -1)
except Exception as e:
pass
else:
assert 0
# Check specifying invalid param name raises exception.
try:
gsapi_get_param(instance, -1, None)
except Exception as e:
pass
else:
assert 0
# Check we can write 64-bit value.
gsapi_set_param(instance, 'foo', 2**40, None)
# Check specifying out-of-range raises exception.
try:
gsapi_set_param(instance, 'foo', 2**40, gs_spt_int)
except Exception as e:
print(e)
assert 'out of range' in str(e)
else:
assert 0
# Check specifying out-of-range raises exception.
try:
gsapi_set_param(instance, 'foo', 2**70, None)
except Exception as e:
print(e)
assert 'out of range' in str(e)
else:
assert 0
print('Checking that we can set and get NumCompies and get same result back')
gsapi_set_param(instance, "NumCopies", 10, gs_spt_i64)
v = gsapi_get_param(instance, "NumCopies", gs_spt_i64)
assert v == 10
for value in False, True:
gsapi_set_param(instance, "DisablePageHandler", value)
v = gsapi_get_param(instance, "DisablePageHandler")
assert v is value
for value in 32, True, 3.14:
gsapi_set_param(instance, "foo", value);
print('gsapi_set_param() %s ok.' % value)
try:
gsapi_get_param(instance, 'foo')
except GSError as e:
pass
else:
assert 0, 'expected gsapi_get_param() to fail'
value = "hello world"
gsapi_set_param(instance, "foo", value, gs_spt_string)
print('gsapi_set_param() %s ok.' % value)
gsapi_set_param(instance, "foo", 123, gs_spt_bool)
try:
gsapi_set_param(instance, "foo", None, gs_spt_bool)
except Exception:
pass
else:
assert 0
# Enumerate all params and print name/value.
print('gsapi_enumerate_params():')
for param, type_ in gsapi_enumerate_params(instance):
value = gsapi_get_param(instance, param, type_)
value2 = gsapi_get_param(instance, param)
assert value2 == value, 'value=%s value2=%s' % (value, value2)
value3 = gsapi_get_param(instance, param, encoding='utf-8')
print(' %-24s type_=%-5s %r %r' % (param, type_, value, value3))
assert not isinstance(value, str)
if isinstance(value, bytes):
assert isinstance(value3, str)
print('Finished')
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