# Write out the perl5i wrapper C program making sure it uses
# the Perl its built with.

use strict;
use warnings;
use File::Spec;

my $file = shift;

# Its going inside double quotes.
my $perl_path = $^X;
$perl_path =~ s{ ([\\"]) }{\\$1}gx;

my $tempdir = File::Spec->tmpdir || "/tmp";

open my $fh, ">", $file or die $!;
printf $fh <<'END', $0, $perl_path, $tempdir;
/* THIS FILE IS GENERATED BY %s
 * Any changes here will be wiped out.  Edit it there instead.
 */

#define DEBUG 0

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

/*
 * Meant to mimic the shell command
 *     exec perl -Mperl5i::latest "$@"
 *
 * This is a C program so it works in a #! line.
 */

int main (int argc, char* argv[]) {
    int i;
    int j;
    const char* perl_cmd = "%s";
    char* perl_args[argc+1];
    char* dash_m = (char *)malloc(sizeof(char) * (strlen(argv[0]) + 20));
    char* program;
    int saw_dash_e = 0;

    strcat(dash_m, "-Mperl5i::cmd=");
    strcat(dash_m, argv[0]);

    perl_args[0] = (char *)perl_cmd;
    perl_args[1] = dash_m;

    for( i = 1, j = 2;  i < argc;  i++ ) {
        char *dash_e = strchr(argv[i], 'e');

        /* Its a one liner */
        if( dash_e && strcmp(dash_e, "e") == 0
            && (strchr(argv[i], '-') == argv[i])
            && (strchr(argv[i], 'M') != argv[i]+1)
        )
        {
            saw_dash_e = 1;

            /* Chop out the -e */
            dash_e[0] = '\0';

            /* If all that's left is a dash, ignore it */
            if( strcmp(argv[i], "-") != 0 ) {
                perl_args[j] = argv[i];
                j++;
            }

            /* Skip the next argument, its the program */
            program = argv[i+1];
            i++;
            continue;
        }

        perl_args[j] = argv[i];
        j++;
    }

    /* Turn one liners into real programs to work around
       a Devel::Declare bug */
    if( saw_dash_e ) {
        char tempfile[] = "%s/perl5i.XXXXXX";
        int fd = mkstemp(tempfile);
        if( fd == -1 ) {
            perror("Could not open temporary file 'tempfile'");
            exit(1);
        }
        FILE *fh = fdopen(fd, "w");
        fprintf( fh, "$0 = '-e';\n" );
        fprintf( fh, "#line 1 \"-e\"\n" );
        fprintf( fh, "%%s", program );
        fclose(fh);

        perl_args[j++] = tempfile;
    }

    /* Argument array must be terminated by a null */
    perl_args[j] = (char *)NULL;

#if DEBUG
    for( i = 0; i <= j; i++ ) {
        printf("perl_args[%%d]: %%s\n", i, perl_args[i]);
    }

    if( saw_dash_e )
        printf("program: %%s\n", program);
#endif

    return execv( perl_cmd, perl_args );
}
END