1 # -*- coding: utf-8; mode: python -*-
2 # pylint: disable=C0103, R0903, R0912, R0915
3 u"""
4 scalable figure and image handling
5 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
6
7 Sphinx extension which implements scalable image handling.
8
9 :copyright: Copyright (C) 2016 Markus Heiser
10 :license: GPL Version 2, June 1991 see Linux/COPYING for details.
11
12 The build for image formats depend on image's source format and output's
13 destination format. This extension implement methods to simplify image
14 handling from the author's POV. Directives like ``kernel-figure`` implement
15 methods *to* always get the best output-format even if some tools are not
16 installed. For more details take a look at ``convert_image(...)`` which is
17 the core of all conversions.
18
19 * ``.. kernel-image``: for image handling / a ``.. image::`` replacement
20
21 * ``.. kernel-figure``: for figure handling / a ``.. figure::`` replacement
22
23 * ``.. kernel-render``: for render markup / a concept to embed *render*
24 markups (or languages). Supported markups (see ``RENDER_MARKUP_EXT``)
25
26 - ``DOT``: render embedded Graphviz's **DOC**
27 - ``SVG``: render embedded Scalable Vector Graphics (**SVG**)
28 - ... *developable*
29
30 Used tools:
31
32 * ``dot(1)``: Graphviz (https://www.graphviz.org). If Graphviz is not
33 available, the DOT language is inserted as literal-block.
34 For conversion to PDF, ``rsvg-convert(1)`` of librsvg
35 (https://gitlab.gnome.org/GNOME/librsvg) is used when available.
36
37 * SVG to PDF: To generate PDF, you need at least one of this tools:
38
39 - ``convert(1)``: ImageMagick (https://www.imagemagick.org)
40 - ``inkscape(1)``: Inkscape (https://inkscape.org/)
41
42 List of customizations:
43
44 * generate PDF from SVG / used by PDF (LaTeX) builder
45
46 * generate SVG (html-builder) and PDF (latex-builder) from DOT files.
47 DOT: see https://www.graphviz.org/content/dot-language
48
49 """
50
51 import os
52 from os import path
53 import subprocess
54 from hashlib import sha1
55 import re
56 from docutils import nodes
57 from docutils.statemachine import ViewList
58 from docutils.parsers.rst import directives
59 from docutils.parsers.rst.directives import images
60 import sphinx
61 from sphinx.util.nodes import clean_astext
62 import kernellog
63
64 Figure = images.Figure
65
66 __version__ = '1.0.0'
67
68 # simple helper
69 # -------------
70
71 def which(cmd):
72 """Searches the ``cmd`` in the ``PATH`` environment.
73
74 This *which* searches the PATH for executable ``cmd`` . First match is
75 returned, if nothing is found, ``None` is returned.
76 """
77 envpath = os.environ.get('PATH', None) or os.defpath
78 for folder in envpath.split(os.pathsep):
79 fname = folder + os.sep + cmd
80 if path.isfile(fname):
81 return fname
82
83 def mkdir(folder, mode=0o775):
84 if not path.isdir(folder):
85 os.makedirs(folder, mode)
86
87 def file2literal(fname):
88 with open(fname, "r") as src:
89 data = src.read()
90 node = nodes.literal_block(data, data)
91 return node
92
93 def isNewer(path1, path2):
94 """Returns True if ``path1`` is newer than ``path2``
95
96 If ``path1`` exists and is newer than ``path2`` the function returns
97 ``True`` is returned otherwise ``False``
98 """
99 return (path.exists(path1)
100 and os.stat(path1).st_ctime > os.stat(path2).st_ctime)
101
102 def pass_handle(self, node): # pylint: disable=W0613
103 pass
104
105 # setup conversion tools and sphinx extension
106 # -------------------------------------------
107
108 # Graphviz's dot(1) support
109 dot_cmd = None
110 # dot(1) -Tpdf should be used
111 dot_Tpdf = False
112
113 # ImageMagick' convert(1) support
114 convert_cmd = None
115
116 # librsvg's rsvg-convert(1) support
117 rsvg_convert_cmd = None
118
119 # Inkscape's inkscape(1) support
120 inkscape_cmd = None
121 # Inkscape prior to 1.0 uses different command options
122 inkscape_ver_one = False
123
124
125 def setup(app):
126 # check toolchain first
127 app.connect('builder-inited', setupTools)
128
129 # image handling
130 app.add_directive("kernel-image", KernelImage)
131 app.add_node(kernel_image,
132 html = (visit_kernel_image, pass_handle),
133 latex = (visit_kernel_image, pass_handle),
134 texinfo = (visit_kernel_image, pass_handle),
135 text = (visit_kernel_image, pass_handle),
136 man = (visit_kernel_image, pass_handle), )
137
138 # figure handling
139 app.add_directive("kernel-figure", KernelFigure)
140 app.add_node(kernel_figure,
141 html = (visit_kernel_figure, pass_handle),
142 latex = (visit_kernel_figure, pass_handle),
143 texinfo = (visit_kernel_figure, pass_handle),
144 text = (visit_kernel_figure, pass_handle),
145 man = (visit_kernel_figure, pass_handle), )
146
147 # render handling
148 app.add_directive('kernel-render', KernelRender)
149 app.add_node(kernel_render,
150 html = (visit_kernel_render, pass_handle),
151 latex = (visit_kernel_render, pass_handle),
152 texinfo = (visit_kernel_render, pass_handle),
153 text = (visit_kernel_render, pass_handle),
154 man = (visit_kernel_render, pass_handle), )
155
156 app.connect('doctree-read', add_kernel_figure_to_std_domain)
157
158 return dict(
159 version = __version__,
160 parallel_read_safe = True,
161 parallel_write_safe = True
162 )
163
164
165 def setupTools(app):
166 u"""
167 Check available build tools and log some *verbose* messages.
168
169 This function is called once, when the builder is initiated.
170 """
171 global dot_cmd, dot_Tpdf, convert_cmd, rsvg_convert_cmd # pylint: disable=W0603
172 global inkscape_cmd, inkscape_ver_one # pylint: disable=W0603
173 kernellog.verbose(app, "kfigure: check installed tools ...")
174
175 dot_cmd = which('dot')
176 convert_cmd = which('convert')
177 rsvg_convert_cmd = which('rsvg-convert')
178 inkscape_cmd = which('inkscape')
179
180 if dot_cmd:
181 kernellog.verbose(app, "use dot(1) from: " + dot_cmd)
182
183 try:
184 dot_Thelp_list = subprocess.check_output([dot_cmd, '-Thelp'],
185 stderr=subprocess.STDOUT)
186 except subprocess.CalledProcessError as err:
187 dot_Thelp_list = err.output
188 pass
189
190 dot_Tpdf_ptn = b'pdf'
191 dot_Tpdf = re.search(dot_Tpdf_ptn, dot_Thelp_list)
192 else:
193 kernellog.warn(app, "dot(1) not found, for better output quality install "
194 "graphviz from https://www.graphviz.org")
195 if inkscape_cmd:
196 kernellog.verbose(app, "use inkscape(1) from: " + inkscape_cmd)
197 inkscape_ver = subprocess.check_output([inkscape_cmd, '--version'],
198 stderr=subprocess.DEVNULL)
199 ver_one_ptn = b'Inkscape 1'
200 inkscape_ver_one = re.search(ver_one_ptn, inkscape_ver)
201 convert_cmd = None
202 rsvg_convert_cmd = None
203 dot_Tpdf = False
204
205 else:
206 if convert_cmd:
207 kernellog.verbose(app, "use convert(1) from: " + convert_cmd)
208 else:
209 kernellog.verbose(app,
210 "Neither inkscape(1) nor convert(1) found.\n"
211 "For SVG to PDF conversion, "
212 "install either Inkscape (https://inkscape.org/) (preferred) or\n"
213 "ImageMagick (https://www.imagemagick.org)")
214
215 if rsvg_convert_cmd:
216 kernellog.verbose(app, "use rsvg-convert(1) from: " + rsvg_convert_cmd)
217 kernellog.verbose(app, "use 'dot -Tsvg' and rsvg-convert(1) for DOT -> PDF conversion")
218 dot_Tpdf = False
219 else:
220 kernellog.verbose(app,
221 "rsvg-convert(1) not found.\n"
222 " SVG rendering of convert(1) is done by ImageMagick-native renderer.")
223 if dot_Tpdf:
224 kernellog.verbose(app, "use 'dot -Tpdf' for DOT -> PDF conversion")
225 else:
226 kernellog.verbose(app, "use 'dot -Tsvg' and convert(1) for DOT -> PDF conversion")
227
228
229 # integrate conversion tools
230 # --------------------------
231
232 RENDER_MARKUP_EXT = {
233 # The '.ext' must be handled by convert_image(..) function's *in_ext* input.
234 # <name> : <.ext>
235 'DOT' : '.dot',
236 'SVG' : '.svg'
237 }
238
239 def convert_image(img_node, translator, src_fname=None):
240 """Convert a image node for the builder.
241
242 Different builder prefer different image formats, e.g. *latex* builder
243 prefer PDF while *html* builder prefer SVG format for images.
244
245 This function handles output image formats in dependence of source the
246 format (of the image) and the translator's output format.
247 """
248 app = translator.builder.app
249
250 fname, in_ext = path.splitext(path.basename(img_node['uri']))
251 if src_fname is None:
252 src_fname = path.join(translator.builder.srcdir, img_node['uri'])
253 if not path.exists(src_fname):
254 src_fname = path.join(translator.builder.outdir, img_node['uri'])
255
256 dst_fname = None
257
258 # in kernel builds, use 'make SPHINXOPTS=-v' to see verbose messages
259
260 kernellog.verbose(app, 'assert best format for: ' + img_node['uri'])
261
262 if in_ext == '.dot':
263
264 if not dot_cmd:
265 kernellog.verbose(app,
266 "dot from graphviz not available / include DOT raw.")
267 img_node.replace_self(file2literal(src_fname))
268
269 elif translator.builder.format == 'latex':
270 dst_fname = path.join(translator.builder.outdir, fname + '.pdf')
271 img_node['uri'] = fname + '.pdf'
272 img_node['candidates'] = {'*': fname + '.pdf'}
273
274
275 elif translator.builder.format == 'html':
276 dst_fname = path.join(
277 translator.builder.outdir,
278 translator.builder.imagedir,
279 fname + '.svg')
280 img_node['uri'] = path.join(
281 translator.builder.imgpath, fname + '.svg')
282 img_node['candidates'] = {
283 '*': path.join(translator.builder.imgpath, fname + '.svg')}
284
285 else:
286 # all other builder formats will include DOT as raw
287 img_node.replace_self(file2literal(src_fname))
288
289 elif in_ext == '.svg':
290
291 if translator.builder.format == 'latex':
292 if not inkscape_cmd and convert_cmd is None:
293 kernellog.warn(app,
294 "no SVG to PDF conversion available / include SVG raw."
295 "\nIncluding large raw SVGs can cause xelatex error."
296 "\nInstall Inkscape (preferred) or ImageMagick.")
297 img_node.replace_self(file2literal(src_fname))
298 else:
299 dst_fname = path.join(translator.builder.outdir, fname + '.pdf')
300 img_node['uri'] = fname + '.pdf'
301 img_node['candidates'] = {'*': fname + '.pdf'}
302
303 if dst_fname:
304 # the builder needs not to copy one more time, so pop it if exists.
305 translator.builder.images.pop(img_node['uri'], None)
306 _name = dst_fname[len(str(translator.builder.outdir)) + 1:]
307
308 if isNewer(dst_fname, src_fname):
309 kernellog.verbose(app,
310 "convert: {out}/%s already exists and is newer" % _name)
311
312 else:
313 ok = False
314 mkdir(path.dirname(dst_fname))
315
316 if in_ext == '.dot':
317 kernellog.verbose(app, 'convert DOT to: {out}/' + _name)
318 if translator.builder.format == 'latex' and not dot_Tpdf:
319 svg_fname = path.join(translator.builder.outdir, fname + '.svg')
320 ok1 = dot2format(app, src_fname, svg_fname)
321 ok2 = svg2pdf_by_rsvg(app, svg_fname, dst_fname)
322 ok = ok1 and ok2
323
324 else:
325 ok = dot2format(app, src_fname, dst_fname)
326
327 elif in_ext == '.svg':
328 kernellog.verbose(app, 'convert SVG to: {out}/' + _name)
329 ok = svg2pdf(app, src_fname, dst_fname)
330
331 if not ok:
332 img_node.replace_self(file2literal(src_fname))
333
334
335 def dot2format(app, dot_fname, out_fname):
336 """Converts DOT file to ``out_fname`` using ``dot(1)``.
337
338 * ``dot_fname`` pathname of the input DOT file, including extension ``.dot``
339 * ``out_fname`` pathname of the output file, including format extension
340
341 The *format extension* depends on the ``dot`` command (see ``man dot``
342 option ``-Txxx``). Normally you will use one of the following extensions:
343
344 - ``.ps`` for PostScript,
345 - ``.svg`` or ``svgz`` for Structured Vector Graphics,
346 - ``.fig`` for XFIG graphics and
347 - ``.png`` or ``gif`` for common bitmap graphics.
348
349 """
350 out_format = path.splitext(out_fname)[1][1:]
351 cmd = [dot_cmd, '-T%s' % out_format, dot_fname]
352 exit_code = 42
353
354 with open(out_fname, "w") as out:
355 exit_code = subprocess.call(cmd, stdout = out)
356 if exit_code != 0:
357 kernellog.warn(app,
358 "Error #%d when calling: %s" % (exit_code, " ".join(cmd)))
359 return bool(exit_code == 0)
360
361 def svg2pdf(app, svg_fname, pdf_fname):
362 """Converts SVG to PDF with ``inkscape(1)`` or ``convert(1)`` command.
363
364 Uses ``inkscape(1)`` from Inkscape (https://inkscape.org/) or ``convert(1)``
365 from ImageMagick (https://www.imagemagick.org) for conversion.
366 Returns ``True`` on success and ``False`` if an error occurred.
367
368 * ``svg_fname`` pathname of the input SVG file with extension (``.svg``)
369 * ``pdf_name`` pathname of the output PDF file with extension (``.pdf``)
370
371 """
372 cmd = [convert_cmd, svg_fname, pdf_fname]
373 cmd_name = 'convert(1)'
374
375 if inkscape_cmd:
376 cmd_name = 'inkscape(1)'
377 if inkscape_ver_one:
378 cmd = [inkscape_cmd, '-o', pdf_fname, svg_fname]
379 else:
380 cmd = [inkscape_cmd, '-z', '--export-pdf=%s' % pdf_fname, svg_fname]
381
382 try:
383 warning_msg = subprocess.check_output(cmd, stderr=subprocess.STDOUT)
384 exit_code = 0
385 except subprocess.CalledProcessError as err:
386 warning_msg = err.output
387 exit_code = err.returncode
388 pass
389
390 if exit_code != 0:
391 kernellog.warn(app, "Error #%d when calling: %s" % (exit_code, " ".join(cmd)))
392 if warning_msg:
393 kernellog.warn(app, "Warning msg from %s: %s"
394 % (cmd_name, str(warning_msg, 'utf-8')))
395 elif warning_msg:
396 kernellog.verbose(app, "Warning msg from %s (likely harmless):\n%s"
397 % (cmd_name, str(warning_msg, 'utf-8')))
398
399 return bool(exit_code == 0)
400
401 def svg2pdf_by_rsvg(app, svg_fname, pdf_fname):
402 """Convert SVG to PDF with ``rsvg-convert(1)`` command.
403
404 * ``svg_fname`` pathname of input SVG file, including extension ``.svg``
405 * ``pdf_fname`` pathname of output PDF file, including extension ``.pdf``
406
407 Input SVG file should be the one generated by ``dot2format()``.
408 SVG -> PDF conversion is done by ``rsvg-convert(1)``.
409
410 If ``rsvg-convert(1)`` is unavailable, fall back to ``svg2pdf()``.
411
412 """
413
414 if rsvg_convert_cmd is None:
415 ok = svg2pdf(app, svg_fname, pdf_fname)
416 else:
417 cmd = [rsvg_convert_cmd, '--format=pdf', '-o', pdf_fname, svg_fname]
418 # use stdout and stderr from parent
419 exit_code = subprocess.call(cmd)
420 if exit_code != 0:
421 kernellog.warn(app, "Error #%d when calling: %s" % (exit_code, " ".join(cmd)))
422 ok = bool(exit_code == 0)
423
424 return ok
425
426
427 # image handling
428 # ---------------------
429
430 def visit_kernel_image(self, node): # pylint: disable=W0613
431 """Visitor of the ``kernel_image`` Node.
432
433 Handles the ``image`` child-node with the ``convert_image(...)``.
434 """
435 img_node = node[0]
436 convert_image(img_node, self)
437
438 class kernel_image(nodes.image):
439 """Node for ``kernel-image`` directive."""
440 pass
441
442 class KernelImage(images.Image):
443 u"""KernelImage directive
444
445 Earns everything from ``.. image::`` directive, except *remote URI* and
446 *glob* pattern. The KernelImage wraps a image node into a
447 kernel_image node. See ``visit_kernel_image``.
448 """
449
450 def run(self):
451 uri = self.arguments[0]
452 if uri.endswith('.*') or uri.find('://') != -1:
453 raise self.severe(
454 'Error in "%s: %s": glob pattern and remote images are not allowed'
455 % (self.name, uri))
456 result = images.Image.run(self)
457 if len(result) == 2 or isinstance(result[0], nodes.system_message):
458 return result
459 (image_node,) = result
460 # wrap image node into a kernel_image node / see visitors
461 node = kernel_image('', image_node)
462 return [node]
463
464 # figure handling
465 # ---------------------
466
467 def visit_kernel_figure(self, node): # pylint: disable=W0613
468 """Visitor of the ``kernel_figure`` Node.
469
470 Handles the ``image`` child-node with the ``convert_image(...)``.
471 """
472 img_node = node[0][0]
473 convert_image(img_node, self)
474
475 class kernel_figure(nodes.figure):
476 """Node for ``kernel-figure`` directive."""
477
478 class KernelFigure(Figure):
479 u"""KernelImage directive
480
481 Earns everything from ``.. figure::`` directive, except *remote URI* and
482 *glob* pattern. The KernelFigure wraps a figure node into a kernel_figure
483 node. See ``visit_kernel_figure``.
484 """
485
486 def run(self):
487 uri = self.arguments[0]
488 if uri.endswith('.*') or uri.find('://') != -1:
489 raise self.severe(
490 'Error in "%s: %s":'
491 ' glob pattern and remote images are not allowed'
492 % (self.name, uri))
493 result = Figure.run(self)
494 if len(result) == 2 or isinstance(result[0], nodes.system_message):
495 return result
496 (figure_node,) = result
497 # wrap figure node into a kernel_figure node / see visitors
498 node = kernel_figure('', figure_node)
499 return [node]
500
501
502 # render handling
503 # ---------------------
504
505 def visit_kernel_render(self, node):
506 """Visitor of the ``kernel_render`` Node.
507
508 If rendering tools available, save the markup of the ``literal_block`` child
509 node into a file and replace the ``literal_block`` node with a new created
510 ``image`` node, pointing to the saved markup file. Afterwards, handle the
511 image child-node with the ``convert_image(...)``.
512 """
513 app = self.builder.app
514 srclang = node.get('srclang')
515
516 kernellog.verbose(app, 'visit kernel-render node lang: "%s"' % (srclang))
517
518 tmp_ext = RENDER_MARKUP_EXT.get(srclang, None)
519 if tmp_ext is None:
520 kernellog.warn(app, 'kernel-render: "%s" unknown / include raw.' % (srclang))
521 return
522
523 if not dot_cmd and tmp_ext == '.dot':
524 kernellog.verbose(app, "dot from graphviz not available / include raw.")
525 return
526
527 literal_block = node[0]
528
529 code = literal_block.astext()
530 hashobj = code.encode('utf-8') # str(node.attributes)
531 fname = path.join('%s-%s' % (srclang, sha1(hashobj).hexdigest()))
532
533 tmp_fname = path.join(
534 self.builder.outdir, self.builder.imagedir, fname + tmp_ext)
535
536 if not path.isfile(tmp_fname):
537 mkdir(path.dirname(tmp_fname))
538 with open(tmp_fname, "w") as out:
539 out.write(code)
540
541 img_node = nodes.image(node.rawsource, **node.attributes)
542 img_node['uri'] = path.join(self.builder.imgpath, fname + tmp_ext)
543 img_node['candidates'] = {
544 '*': path.join(self.builder.imgpath, fname + tmp_ext)}
545
546 literal_block.replace_self(img_node)
547 convert_image(img_node, self, tmp_fname)
548
549
550 class kernel_render(nodes.General, nodes.Inline, nodes.Element):
551 """Node for ``kernel-render`` directive."""
552 pass
553
554 class KernelRender(Figure):
555 u"""KernelRender directive
556
557 Render content by external tool. Has all the options known from the
558 *figure* directive, plus option ``caption``. If ``caption`` has a
559 value, a figure node with the *caption* is inserted. If not, a image node is
560 inserted.
561
562 The KernelRender directive wraps the text of the directive into a
563 literal_block node and wraps it into a kernel_render node. See
564 ``visit_kernel_render``.
565 """
566 has_content = True
567 required_arguments = 1
568 optional_arguments = 0
569 final_argument_whitespace = False
570
571 # earn options from 'figure'
572 option_spec = Figure.option_spec.copy()
573 option_spec['caption'] = directives.unchanged
574
575 def run(self):
576 return [self.build_node()]
577
578 def build_node(self):
579
580 srclang = self.arguments[0].strip()
581 if srclang not in RENDER_MARKUP_EXT.keys():
582 return [self.state_machine.reporter.warning(
583 'Unknown source language "%s", use one of: %s.' % (
584 srclang, ",".join(RENDER_MARKUP_EXT.keys())),
585 line=self.lineno)]
586
587 code = '\n'.join(self.content)
588 if not code.strip():
589 return [self.state_machine.reporter.warning(
590 'Ignoring "%s" directive without content.' % (
591 self.name),
592 line=self.lineno)]
593
594 node = kernel_render()
595 node['alt'] = self.options.get('alt','')
596 node['srclang'] = srclang
597 literal_node = nodes.literal_block(code, code)
598 node += literal_node
599
600 caption = self.options.get('caption')
601 if caption:
602 # parse caption's content
603 parsed = nodes.Element()
604 self.state.nested_parse(
605 ViewList([caption], source=''), self.content_offset, parsed)
606 caption_node = nodes.caption(
607 parsed[0].rawsource, '', *parsed[0].children)
608 caption_node.source = parsed[0].source
609 caption_node.line = parsed[0].line
610
611 figure_node = nodes.figure('', node)
612 for k,v in self.options.items():
613 figure_node[k] = v
614 figure_node += caption_node
615
616 node = figure_node
617
618 return node
619
620 def add_kernel_figure_to_std_domain(app, doctree):
621 """Add kernel-figure anchors to 'std' domain.
622
623 The ``StandardDomain.process_doc(..)`` method does not know how to resolve
624 the caption (label) of ``kernel-figure`` directive (it only knows about
625 standard nodes, e.g. table, figure etc.). Without any additional handling
626 this will result in a 'undefined label' for kernel-figures.
627
628 This handle adds labels of kernel-figure to the 'std' domain labels.
629 """
630
631 std = app.env.domains["std"]
632 docname = app.env.docname
633 labels = std.data["labels"]
634
635 for name, explicit in doctree.nametypes.items():
636 if not explicit:
637 continue
638 labelid = doctree.nameids[name]
639 if labelid is None:
640 continue
641 node = doctree.ids[labelid]
642
643 if node.tagname == 'kernel_figure':
644 for n in node.next_node():
645 if n.tagname == 'caption':
646 sectname = clean_astext(n)
647 # add label to std domain
648 labels[name] = docname, labelid, sectname
649 break
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