[SOLVED] Python Results Converted To C Struct Header File

metallica1973 · 10-21-2015, 03:09 PM

I created python code that produce output in the form of:

Code:

moses-red-sea=1.00.03
genesis-snake=2.03
deliverance=5.0.010

I need to take this output and create a "C" header file and have it look like this:

Code:

struct {

        char *name;
        char *fixed_version;

} filename_versions[] = {

{"moses-red-sea","1.00.03"},
{"genesis-snake","2.03"},
{"deliverance","5.0.010"},
        {NULL, NULL}
};

I have looked at Python modules "struct":

https://docs.python.org/2/library/struct.html

and "ctype"

https://docs.python.org/2/library/ctypes.html

but am not sure if thats the ticket. Can someone shed some light? Thank you in advance.

Rinndalir · 10-21-2015, 08:34 PM

I guess py2c did not do what you want or expect??? What have you gotten so far?

HMW · 10-22-2015, 06:04 AM

Hi!

Why don't you just use the output from your first Python code as input to another Python program, that can then write the C header to file?

With your output as my input, and my short (28 lines) Python program, I get this result (I obviously use print() instead of write() here):

Code:

./met1973.py 
struct {

        char *name;
        char *fixed_version;

} filename_versions[] = {

{"moses-red-sea","1.00.03"},
{"genesis-snake","2.03"},
{"deliverance","5.0.010"},
        {NULL, NULL}
};

Maybe I am missing the point, but this is how I would do it. And, well, have actually done it! So, to reiterate; use the output from Python program 1 as input to Python program 2. Or even better, why don't you write a single Python program that does everything at once. Seems the most efficient to me, but I don't have the whole picture.

Best regards,
HMW

metallica1973 · 10-22-2015, 09:55 AM

HMW, thanks for your reply. It was suggested to me basically what you are saying. So essentially just treat it as regular Python output and just redirect the output to a regular file (ex. versions.h) so it can be used by the existing C code in place.

HMW · 10-22-2015, 11:25 AM

Quote:

Originally Posted by metallica1973

HMW, thanks for your reply. It was suggested to me basically what you are saying. So essentially just treat it as regular Python output and just redirect the output to a regular file (ex. versions.h) so it can be used by the existing C code in place.

Yeah, it makes sense to me. Holler if you want some assistance!

Best regards,
HMW

grail · 10-22-2015, 12:10 PM

I got a 19 line bash script

metallica1973 · 11-09-2015, 09:30 AM

Thanks everyone for pointing me in the right direction. Here is a snippet of what I did to help anyone else out who is trying to do the samething:

Code:

dest=open('wp.h', 'a+')
dest.write('struct {\n')
dest.write('{0:>12} {1:6}\n'.format('char','*name;'))
dest.write('{0:>12} {1:16}\n\n'.format('char','*fixed_versions;'))
dest.write('} filename_versions[] = {\n\n')
   blah blah blah .....
dest.write('{0:>19}\n'.format('{NULL, NULL}'))
dest.write('{0}\n'.format('};'))
dest.close()

A sample output:

Code:

struct {

        char *name;
        char *fixed_version;

} filename_versions[] = {

{"moses-red-sea","1.00.03"},
{"genesis-snake","2.03"},
{"deliverance","5.0.010"},
        {NULL, NULL}
};

grail · 11-09-2015, 10:07 AM

ummm ... don't we need to see the 'blah blah blah' if we to know how you got the data in the correct format? I mean the bit you have shown is nice but is essentially just a list of print statements.

HMW · 11-09-2015, 10:50 AM

Quote:

Originally Posted by metallica1973

Thanks everyone for pointing me in the right direction. Here is a snippet of what I did to help anyone else out who is trying to do the samething:

Code:

dest=open('wp.h', 'a+')
dest.write('struct {\n')
dest.write('{0:>12} {1:6}\n'.format('char','*name;'))
dest.write('{0:>12} {1:16}\n\n'.format('char','*fixed_versions;'))
dest.write('} filename_versions[] = {\n\n')
   blah blah blah .....
dest.write('{0:>19}\n'.format('{NULL, NULL}'))
dest.write('{0}\n'.format('};'))
dest.close()

A sample output:

Code:

struct {

        char *name;
        char *fixed_version;

} filename_versions[] = {

{"moses-red-sea","1.00.03"},
{"genesis-snake","2.03"},
{"deliverance","5.0.010"},
        {NULL, NULL}
};

Hi!

I opted for saving the static information in a variable instead. Thus you don't have to write more than once (or print in my case).
Here's my approach:

Code:

#!/usr/bin/env python3

out = """struct {

        char *name;
        char *fixed_version;

} filename_versions[] = {

"""

with open("infile.txt") as infile:
    for line in infile:
        line = line.rstrip()
        lineSplit = line.split("=")
        out += "{\"" + lineSplit[0] + "\",\"" + lineSplit[1] + "\"},\n"

out = out[:-1] # Remove the unwanted \n from the final loop

out += """
        {NULL, NULL}
};
"""

print(out)

exit(0)

Best regards,
HMW

grail · 11-09-2015, 01:26 PM

I understand keeping it all in python was easier, but here was my shell script all the same

Code:

#!/usr/bin/env bash

cat >wp.h<<EOF
struct {

        char *name;
        char *fixed_version;

} filename_versions[] = {

$(while IFS== read -r name num
  do
    echo "{\"$name\",\"$num\"},"
  done)
         {NULL, NULL}
};
EOF

Which I ran as:

Code:

cat data | ./struct.sh