main.cpp

#include "common.h"
#include "ZString.h"
#include "ZReader.h"
#include "ZScanner.h"
#include "ZTimer.h"
#include <getopt.h>

int nWorkers = 1;
const char* sRunner = "/usr/bin/perl";
const char* sScript = 0;

long asMB(double n) {
    return (long)(n / (1024 * 1024));
}

int rateMB(double r, long dt) {
    if (0 == dt) {
        return 0;
    }
    r /= dt; // bytes per millisecond
    r *= 1000; // bytes per second
    r /= 1024 * 1024; // megabytes per second
    return (int)r; // fraction is not significant
}

void usage() {
    fprintf(stderr,
        "Usage: feed-workers [ options ] files...\n"
        "Where options are:\n"
        "  -n N        number of worker processes\n"
        "  -r run      name of executable to run as a worker (default is /usr/bin/perl)\n"
        "  -s script   name of script (passed as argument to worker)\n"
        "The lines read from given list of files are distributed equally among the workers.\n"
        );
    exit(3);
}

const char* now() {
    time_t t = time(0);
    char* s = ctime(&t);
    char* p = strchr(s,'\n');
    *p = 0;
    return s;
}

int main(int ac, char** av) {
	TRACE_FN(main);
    for (;;) {
        int c = getopt(ac, av, "n:r:s:");
        if (EOF == c) break;
        switch (c) {
        case 'n': nWorkers = atoi(optarg); break;
        case 'r': sRunner = optarg; break;
        case 's': sScript = optarg; break;
        default: usage();
        }
    }
    fprintf(stderr,"TIME %s\n",now());
    ZTimer t;
    ZScanner scanner;
    VERIFY(scanner.openTo(nWorkers,sRunner,sScript));
    if (ac <= optind) {
        ZReader reader;
        scanner.onFile("STDIN");
        reader.scanFile(scanner);
    } else {
        ZReader::scanFiles(scanner,optind,ac,av);
    }
    scanner.closeWorkers();
    t.split();
    fprintf(stderr,"TIME %s\n",now());
    fprintf(
        stderr,
        "Elapsed (ms): %ld"
        ", total (MB): %ld"
        "\n",
        (long)t.elapsed(),
        asMB(scanner.cbTotal)
        );
    int v = rateMB(scanner.cbTotal, t.elapsed());
    // Report rates only if somewhat meaningful
    if (1 < v) {
        fprintf(stderr,"Scanned %d MB/s\n",v);
    }
    return 0;
}