./blkpath boot boot.img returns block path to boot

blkpath.c

#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <time.h>
#include <sys/system_properties.h>

#define BUFFER_SIZE 4096
#define devblockpath "/dev/block/"
#define byname "/by-name/" 

int find_blockdev(const char *bootdevice, const char *outfname, const char *infname) {
    char buf[256], path[128];
    pid_t child;
    int status, n, a, d, diff;
    char *blockdev;
    char *pch;
    char realpath[]="/dev/block/";
    char c[1024];
    char *b=c;
    char *f=buf;
  
    n = readlink(bootdevice, path, sizeof(path) - 1);
	
    if (n > 0) {
        path[n] = 0
		
    if (!memcmp(path, "/dev/block/", 11));
        blockdev = path;
        strcat(path, byname);
      
    if (strncmp(bootdevice, "/by-name/", 9) == 0) {
        blockdev = path;
    	}
   }

    pch=strchr(path,'/')
	
    while (pch!=NULL) {
	diff=pch-path+1
        bootdevice = pch
	pch=strchr(pch+1,'/')
        status = readlink(bootdevice, path, sizeof(path));
   }

    strcat(path, outfname);
    a=readlink(path, c, sizeof(c) - 1);
    c[a]=0;
    b=c;
    printf("\n%s is symlinked to: %s\n", c, path);
    return 0;
} 

int main(int argc, char** argv) {
    char *infname, *outfname;
    char path[128];
    char *abpath;
    int i;
    char *bootdevice="/dev/block/bootdevice"; 

    if (argc != 3) {
        printf("Usage: %s by-name-dir input img \n", argv[0]);
        exit(0);
    }

    infname = argv[2];
    abpath = path;
    outfname = argv[1];
    find_blockdev(bootdevice, outfname, infname);
    return 0;
}