#define _POSIX_PTHREAD_SEMANTICS 1
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <unistd.h>
#include <dirent.h>
#include <pthread.h>
   
char *nazwa;
char **slowa;
unsigned int ilosc; //ilosc slow

unsigned int ilosc_watkow = 0;
pthread_mutex_t ilosc_watkow_mutex = PTHREAD_MUTEX_INITIALIZER;
 
void *dofile(void *arg){
    char *file = (char*) arg;
    int fd,res;
    char *plik,*ptr;
    off_t rozmiar;
    unsigned int n;
    
    if ((fd = open(file,O_RDWR))<0) {
	perror("open");
	
	free(file);
	pthread_mutex_lock(&ilosc_watkow_mutex);
	ilosc_watkow--;
	pthread_mutex_unlock(&ilosc_watkow_mutex);	
	
	return -1;
    };
    
    rozmiar = lseek (fd,0,SEEK_END);
    lseek (fd,0,SEEK_SET);
    
    if (rozmiar == 0){
	fprintf(stderr,"%s: pusty plik!\n",file);
	close(fd);
	
	free(file);
	pthread_mutex_lock(&ilosc_watkow_mutex);
	ilosc_watkow--;
	pthread_mutex_unlock(&ilosc_watkow_mutex);	

	return -1;
    };
    plik = (char *) mmap(0,rozmiar,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0);
         
    if (plik == MAP_FAILED) {
	perror("mmap");
	close(fd);
		
	free(file);
	pthread_mutex_lock(&ilosc_watkow_mutex);
	ilosc_watkow--;
	pthread_mutex_unlock(&ilosc_watkow_mutex);	

	return -1;
    };
    
    for (n=0;n<ilosc;n++) {
	ptr = plik;
	while (ptr<(plik+rozmiar-strlen(slowa[n])))
	    if (memcmp(ptr,slowa[n],strlen(slowa[n]))==0)
	    {
		memset(ptr,'*',strlen(slowa[n]));
		ptr +=strlen(slowa[n]);
	    } else
		ptr++;
    };
    
    res = 0;
    
    if (msync(plik,rozmiar, MS_SYNC)!=0) {
	perror("msync");
	res = -1;
    };
    
    if (munmap(plik,rozmiar)!=0){
	perror("munmap");
	res = -1;
    };
    
    close(fd);
    	
    free(file);
    pthread_mutex_lock(&ilosc_watkow_mutex);
    ilosc_watkow--;
    pthread_mutex_unlock(&ilosc_watkow_mutex);	

    return res;
};


int glob(char *where) {
    
    fprintf(stderr,"wchodze %s\n",(where)?where:".");
    
    if (where && (chdir(where) !=0)) {
	perror("chdir");
	return -1;
    };
    
    int ret = 0;
    
    DIR *dir = opendir(".");
    
    if (!dir){
	perror("opendir");
	ret = -1;
	goto out;
    };    
    
    struct dirent *de;
    
    while ((de=readdir(dir))) {
	if ((strcmp(de->d_name,".")==0) || (strcmp(de->d_name,"..")==0))
	    continue;
	    
	struct stat st;
	
	if (stat(de->d_name,&st)!=0)
	    continue;
	
	if (S_ISDIR(st.st_mode))
	    glob(de->d_name);
	else if(S_ISREG(st.st_mode)&&(strcmp(de->d_name,nazwa)==0)) {
	    
	    char *cwd = getcwd(0,256);
	    
	    if (!cwd) {
		perror("getcwd");
		continue;
	    }
	    	
	    char *fname = malloc(strlen(cwd)+strlen(de->d_name)+1+1);
	    
	    if (!fname) {
		perror("malloc");
		continue;
	    }
	    
	    sprintf(fname,"%s/%s",cwd,de->d_name);
	    free(cwd);
	    
	    pthread_mutex_lock(&ilosc_watkow_mutex);
	    ilosc_watkow++;
	    pthread_mutex_unlock(&ilosc_watkow_mutex);	
	    
	    if (pthread_create(0,0,dofile,fname)!=0){
		perror("pthread_create");
		ret = -1;
	
		free(fname);
		
		pthread_mutex_lock(&ilosc_watkow_mutex);
	        ilosc_watkow--;
		pthread_mutex_unlock(&ilosc_watkow_mutex);		
	    }
	    	    
	}    
    };

    closedir(dir);
    
out:
    if (where) {
	fprintf(stderr,"%s ..\n",where);
	chdir("..");
    };
    
    return ret;
};

int main(int argc, char *argv[]){
    
    if (argc < 3) {
	fprintf(stderr,"Uzycie: %s plik slowo1 (...) slowoN\n",argv[0]);
	return -1;
    };
    
    nazwa = argv[1];
    ilosc = argc-2;
    slowa = argv+2;
    
    int ret = glob(0);
    
    while (1) {
	pthread_mutex_lock(&ilosc_watkow_mutex);
	if (!ilosc_watkow)
	    return ret;
	pthread_mutex_unlock(&ilosc_watkow_mutex);	
	sleep (2);
    };
    
};