Hi Bruce,
On Mon, Oct 16, 2023 at 4:06 PM Bruce Richardson
<bruce.richard...@intel.com> wrote:
>
> The DPDK commandline library is widely used by apps and examples within
> DPDK, but it is not documented in our programmers guide and it requires
> a lot of boilerplate code definitions in order to used. We can improve
> this situation by creating a simple python script to automatically
> generate the boilerplate from a list of commands.
>
> This patchset contains a new documentation chapter on cmdline library,
> going through step-by-step how to add commands and create the necessary
> token lists and parse contexts.
>
> Following that initial doc patch, the set then contains a
> boilerplate-generating script, as well as a set of four patches showing
> its use, by converting four examples to use the script instead of
> having the hard-coded boilerplate. Once the script is used, adding a new
> command becomes as simple as adding the desired command to the .list
> file, and then writing the required function which will be called for
> that command. No other boilerplate coding is necessary.
>
> Script obviously does not cover the full range of capabilities of the
> commandline lib, but does cover the most used parts. The code-saving to
> each of the examples by auto-generating the boilerplate is significant,
> and probably more examples with commandlines can be converted over in
> future.
This is not something blocking for the series, but I had a quick try
with testpmd to see where this series stands.
I hit, right off the bat, some of those limitations, but I think there
are not that difficult to deal with.
- testpmd accepts both "help" and "help <section>" commands.
But the cmdline library does not provide a way (afair) for specifiying
this "optional" aspect.
And it can't be expressed with this series current syntax since
generated symbols would conflict if we ask for two "help" commands.
My quick hack was to introduce a way to select the prefix of the
generated symbols.
There may be a better way, like finding a better discriminant for
naming symbols...
But, on the other hand, the symbols prefix might be something a
developer wants to control (instead of currently hardcoded cmd_
prefix).
@@ -20,6 +20,12 @@ def process_command(tokens, cfile, comment):
"""Generate the structures and definitions for a single command."""
name = []
+ prefix, sep, cmd_name = tokens[0].partition(':')
+ if cmd_name:
+ tokens[0] = cmd_name
+ else:
+ prefix = 'cmd'
+
if tokens[0].startswith('<'):
print('Error: each command must start with at least one
literal string', file=sys.stderr)
sys.exit(1)
(etc... I am not copying the rest of the diff)
I then used as:
cmd_brief:help # help: Show help
help <STRING>section # help: Show help
- Multi choice fixed strings is something that is often used in
testpmd, like here, in the help <section> command.
Here is my quick hack:
diff --git a/buildtools/dpdk-cmdline-gen.py b/buildtools/dpdk-cmdline-gen.py
index 3b41fb0493..e8c9e079de 100755
--- a/buildtools/dpdk-cmdline-gen.py
+++ b/buildtools/dpdk-cmdline-gen.py
@@ -35,7 +35,11 @@ def process_command(tokens, cfile, comment):
for t in tokens:
if t.startswith('<'):
t_type, t_name = t[1:].split('>')
- t_val = 'NULL'
+ if len(t_type.split('(')) == 2:
+ t_type, t_val = t_type.split('(')
+ t_val = '"' + t_val.split(')')[0] + '"'
+ else:
+ t_val = 'NULL'
else:
t_type = 'STRING'
t_name = t
@@ -113,7 +117,7 @@ def process_commands(infile, hfile, cfile, ctxname):
continue
if '#' not in line:
line = line + '#' # ensure split always works, even if
no help text
- tokens, comment = line.split('#', 1)
+ tokens, comment = line.rsplit('#', 1)
instances.append(process_command(tokens.strip().split(),
cfile, comment.strip()))
print(f'static __rte_used cmdline_parse_ctx_t {ctxname}[] = {{')
Which translates as:
cmd_brief:help # help: Show help
help <STRING(all#control#display#config#ports)>section # help: Show help
>
> The "cmdline" example itself, is not converted over, as it should
> probably remain as a simple example of direct library use without the
> script.
+1
--
David Marchand
