YoWASP yosys fails to generate SVG diagrams

[rw1nkler]

Currently, YoWASP Yosys fails to generate SVG diagrams. However, the .dot file is created correctly in the output directory.
The problem seems to be related to dot execution:

3. Generating Graphviz representation of design.
Writing dot description to `yosys.dot'.
Dumping module ADDER to page 1.
Exec: dot -Tsvg 'yosys.dot' > 'yosys.svg.new' && mv 'yosys.svg.new' 'yosys.svg'

Steps to reproduce:

wget https://raw.githubusercontent.com/SymbiFlow/sphinxcontrib-verilog-diagrams/master/tests/verilog/adder.v
python3 -c "from yowasp_yosys import *; run_yosys(['-p', 'prep -top ADDER ; cd ADDER; ; show -format svg -prefix yosys', 'adder.v'])"

Comparison with standard Yosys:

wget https://raw.githubusercontent.com/SymbiFlow/sphinxcontrib-verilog-diagrams/master/tests/verilog/adder.v
yosys -p 'prep -top ADDER ; cd ADDER; ; show -format svg -prefix yosys' adder.v

[whitequark]

Yeah, there needs to be a custom hostcall used to implement Yosys' exec_command. I had planned to implement it but other tasks were higher priority.

[whitequark]

In the end I feel that this functionality is not important enough to warrant being implemented. Plus it would cause difficulty for the JavaScript port.