Contents of /wx-0.5/gpp.pike:
#!/usr/local/bin/pike
/*
wxPike - (c) 2005 Julio César Gázquez
gpp.pike:
Small generic preprocessor
Note: gpp is not doing macro replacement at this time,
as was not in my needs.
*/
string ppd="#";
mapping (string:string) macros;
int parseNestLevel, outputNestLevel;
Stdio.File out;
void pp_define(string name,string value)
{
macros[name]=value;
}
void pp_undef(string name)
{
macros-= ({ name });
}
int pp_include(string name)
{
Stdio.FILE in;
in=Stdio.FILE(name,"r");
int r=parse(in);
in->close();
}
string _eval(string word)
{
string v=macros[word];
if (zero_type(v)) v=word;
return v;
}
int eval(array(string) words)
{
string a=_eval(words[0]);
string op=words[1];
string b=_eval(words[2]);
int result;
switch (op) {
case "==":
result=a==b;
break;
case "!=":
result=a!=b;
break;
case ">":
result=a>b;
break;
case "<":
result=a<b;
break;
case ">=":
result=a>=b;
break;
case "<=":
result=a<=b;
break;
}
return result;
}
void pp_if(int cond)
{
if (cond && outputNestLevel==parseNestLevel)
outputNestLevel++;
parseNestLevel++;
}
void pp_else()
{
if (outputNestLevel==parseNestLevel) // Cond was true
outputNestLevel--; // then skip else block
else if (outputNestLevel==parseNestLevel-1) // Cond was false
outputNestLevel++; // Enter in else block
// else, failed in an outer level, keep discarding output
}
void pp_endif()
{
if (outputNestLevel==parseNestLevel)
outputNestLevel--;
parseNestLevel--;
}
int parse(Stdio.FILE in)
{
string line;
while (line=in->gets()) {
array(string) words = line / " ";
if (words[0]==ppd+"define") {
pp_define(words[1],line[search(line,words[2])..]);
} else if (words[0]==ppd+"undef") {
pp_undef(words[1]);
} else if (words[0]==ppd+"include") {
if (pp_include(words[1]))
return 1;
} else if (words[0]==ppd+"if") {
pp_if(eval(words[1..]));
} else if (words[0]==ppd+"ifdef") {
pp_if(!zero_type(macros[words[1]]));
} else if (words[0]==ppd+"ifndef") {
pp_if(zero_type(macros[words[1]]));
} else if (words[0]==ppd+"else") {
pp_else();
} else if (words[0]==ppd+"endif") {
pp_endif();
} else
if (parseNestLevel==outputNestLevel) {
out->write("%s\n",line);
}
}
return 0;
}
int main(int argc,array(string)argv)
{
Stdio.FILE in;
if (argc>1)
if (argv[1][0..3]=="-ppd") {
ppd=argv[1][4..4];
argc--;
argv=argv-({ argv[1] });
}
if (argc>1) {
in=Stdio.FILE(argv[1],"r");
if (argc>2) {
out=Stdio.File(argv[2],"cwt");
} else {
out=Stdio.stdout;
}
} else {
in=Stdio.stdin;
out=Stdio.stdout;
}
parseNestLevel=0;
outputNestLevel=0;
macros=([ ]);
return parse(in);
}
modules.gotpike.org