Inline C discovery

fredo2906 has asked for the wisdom of the Perl Monks concerning the following question:

Coming back with a new question. I am not a pro with C, so forgive me if the code is ugly. I would like to pass an array of string to a C function, loop into it and compare each string in that array if it matches a substring. Something I am pretty sure it is very easy to accomplish, but i am having issues. I google for an example, but what I found was related to numbers. Any help, clue would be nice.

my @a = ("AAAA", "BBBB", "CCCCC");
my $size = $#a;
my $p1 = pack "(A*)*", @a;
print array_search($size,$p1,"B");


__END__
__C__
#include <stdio.h>
void hello_world() {
        printf ("Hello CDRs checkers!\n");
}
//s1 is the substring, s2 is the string
int fastcmp ( char *p1, char *p2 ) {
    int i;
    for( i = 0; i < sizeof(p1); ++i ) {
        if( p1[i] != p2[i] ) {
            return 0;
        }
    }
    return 1;
}
int array_search(int size,char *a1, SV *s1){
        STRLEN bytes1;
        char *p1;
        char *p2 = (char *) a1;
        long a1_size,i;
        p1 = SvPV(s1,bytes1);
        for(i=0;i<size;++i){
            if (fastcmp(p1,p2[i])){
                return 1;
            }
        }
        return 0;
}
[download]

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Re: Inline C discovery by fredo2906 (Acolyte) on Feb 20, 2014 at 06:55 UTC
Finally after looking deeper I found another way to handle arrays and not using pack. Update: fastcmp optimized. my @a = ("AAAA", "BBBB", "CCCCC"); print array_search(\@a,"B"); __END__ __C__ #include <stdio.h> void hello_world() { printf ("Hello CDRs checkers!\n"); } //s1 is the substring, s2 is the string int fastcmp ( char p1, char p2 ) { int count = 0; while( p1 ){ char a = p1, b = p2; while( a && a == b ) {a++;b++;} count += !b; ++p1; } return count; } int array_search(AV a1, SV s1){ STRLEN bytes1; char p1; long a1_size,i; a1_size = av_len(a1); //printf ("%d\n",a1_size); //printf ("%s\n",SvPV_nolen (elem)); p1 = SvPV(s1,bytes1); for(i=0;i<=a1_size;++i){ SV* elem = av_fetch(a1, i, 0); printf("%s %s\n",p1, SvPV_nolen (elem)); if (fastcmp(p1,SvPV_nolen (elem)) > 0){ return 1; } } return 0; } [download] This will produce : `B AAAA String size: 1 Char at 0 is B = A B BBBB String size: 1 Char at 0 is B = B 1` [download]	[reply] [d/l] [select]

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Re: Inline C discovery
by fredo2906 (Acolyte) on Feb 20, 2014 at 06:55 UTC

my @a = ("AAAA", "BBBB", "CCCCC");
print array_search(\@a,"B");


__END__
__C__
#include <stdio.h>
void hello_world() {
        printf ("Hello CDRs checkers!\n");
}
//s1 is the substring, s2 is the string
int fastcmp ( char *p1, char *p2 ) {
  int count = 0;
  while( *p1 ){
    char *a = p1, *b = p2;
    while( *a && *a == *b ) {a++;b++;}
    count += !*b;
    ++p1;
  }
  return count;
}

int array_search(AV *a1, SV *s1){
        STRLEN bytes1;
        char *p1;
        long a1_size,i;
        a1_size = av_len(a1);
        //printf ("%d\n",a1_size);
        //printf ("%s\n",SvPV_nolen (*elem));
        p1 = SvPV(s1,bytes1);
        for(i=0;i<=a1_size;++i){
        SV** elem = av_fetch(a1, i, 0);
        printf("%s %s\n",p1, SvPV_nolen (*elem));
            if (fastcmp(p1,SvPV_nolen (*elem)) > 0){
                return 1;
                }
        }
        return 0;
}
[download]

This will produce :

B AAAA
String size: 1
Char at 0 is B = A
B BBBB
String size: 1
Char at 0 is B = B
1
[download]

[reply]
[d/l]
[select]