update .c with cpp code

persistentStorage.c

@@ -3,9 +3,16 @@
 #include <assert.h>
 #include <unistd.h>
 #include <string.h>
+// #include <cstdlib>
 #include<fcntl.h> 
+#include "storage.h"
+#include <iostream>
+#include<semaphore.h>
+using namespace std;
 
-
+pthread_mutex_t m;
+sem_t w;
+int readercout=0;
 
 struct n1
 {
@@ -33,6 +40,13 @@ struct n2
 struct n1 *h1=NULL;
 struct n2 *h2=NULL;
 unsigned int nooffiles=0;
+
+void initializeStorageVariables()
+{
+	pthread_mutex_init(&m, NULL);
+	sem_init(&w, 0,1);
+}
+
 struct n2 * check(struct n2 *h2){
 	while (1)
 	{
@@ -271,7 +285,7 @@ struct n1 * insert(struct n1 *r,char * key){
 }
 
 
-struct n1* find=NULL;
+struct n1* finding=NULL;
 struct n1* pre;
 struct n1* fpre(struct n1 *r){
 	if(r->p2==NULL){
@@ -366,19 +380,19 @@ struct n1* del(struct n1*r,char *key){
 	}
 	if((tt=strcmp(key,r->key))==0){//both are equal
 		if(r->p1==NULL&&r->p2==NULL){
-			find=r;
+			finding=r;
 			return NULL;
 		}
 		if(r->p1==NULL){
-			find=r;
+			finding=r;
 			return r->p2;
 
 		}
 		if(r->p2==NULL){
-			find=r;
+			finding=r;
 			return r->p1;
 		}
-		find=r;
+		finding=r;
 		fpre(r->p1);
 		pre->p1=r->p1;
 		pre->p2=r->p2;
@@ -554,47 +568,92 @@ struct n1* del(struct n1*r,char *key){
 
 }
 
-char * GET(char * key){
+string GETT(char * key){
+	pthread_mutex_lock(&m);
+	readercout+=1;
+	if(readercout==1){
+		sem_wait(&w);
+	}
+	
+	pthread_mutex_unlock(&m);
+
+
+
+
+
 	int tt;
 	struct n1 *dh=h1;
-	while(1){
-		if(dh==NULL){
-		printf("The key is not present\n");
-		return NULL;
+	while(1)
+	{
+		if(dh==NULL)
+		{
+			string s(1, (char)240);
+			string result = s + "Get key not found";
+			printf("The key is not present\n");
+			// record[0]=240;
+			// record[1]='\0';
+			// char *pointer=record;
+			pthread_mutex_lock(&m);
+			readercout-=1;
+			if(readercout==0){
+				sem_post(&w);
+							}
+	
+			pthread_mutex_unlock(&m);
 
-	}
-	else{
-		printf("%s = %s \n",key ,dh->key);
-		if((tt=strcmp(key,dh->key))==0){
-			char filename2[10];
-			strcpy(filename2,dh->filename);
-			FILE *f=fopen(strcat(filename2,".txt"),"r");
-			char record[257];
-			fseek(f,dh->lineno*257,SEEK_SET);
-			fgets(record,256,f);
-			fclose(f);
-			int sp=0;
-			while (record[sp]!='#')
+			return result;
+		}
+		else
+		{
+			// printf("%s = %s \n",key ,dh->key);
+			if((tt=strcmp(key,dh->key))==0)
 			{
-				sp=sp+1;
+				char filename2[10];
+				strcpy(filename2,dh->filename);
+				int fd1=open(strcat(filename2,".txt"),O_RDWR);
+				char record[257];
+				lseek(fd1,dh->lineno*257,SEEK_SET);
+				// fgets(record,256,f);
+				read(fd1,record, 256);
+				// fclose(f);
+				write(STDOUT_FILENO, record, 256);
+				write(STDOUT_FILENO, "\n", 1);
+				close(fd1);
+				int sp=0;
+				while (record[sp]!='#')
+				{
+					sp=sp+1;
+				}
+				record[sp]='\0';
+				string result=record;
+				// char *recor=record;
+				// return recor;
+				pthread_mutex_lock(&m);
+				readercout-=1;
+				if(readercout==0){
+					sem_post(&w);
+							}
+	
+				pthread_mutex_unlock(&m);
+
+
+				return result;
+				
+			}
+			else if(tt>0)
+			{
+				dh=dh->p2;
+			}
+			else{
+				dh=dh->p1;
 			}
-			record[sp]='\0';
-			char *recor=record;
-			return recor;
-			
-		}
-		else if(tt>0){
-			dh=dh->p2;
-		}
-		else{
-			dh=dh->p1;
 		}
-
-	}
 	}
 }
 
-void PUT(char *key,char *value){
+void PUTT(char *key,char *value){
+	sem_wait(&w);
+	// printf("key = %s\nvalue=%s",key, value);
 	h1=insert(h1,key);
 	char filename2[10];
 	strcpy(filename2,add->filename);
@@ -648,7 +707,9 @@ void PUT(char *key,char *value){
 		write(n,ts,257);
 		close(n);
 	}
-	
+	// printf("PUTT completed\n");
+		sem_post(&w);
+
 }
 
 
@@ -676,60 +737,64 @@ struct n2 * checkfile(struct n2 *h2,char *s){
 	
 }
 
-
-
-void DEL(char *key){
+string DELL(char *key){
+	sem_wait(&w);
 	h1=del(h1,key);
 	// write(STDOUT_FILENO,"came out of del \n",17);
-	if(find==NULL){
+	// printf("key = %s\n", key);
+	if(finding==NULL){
 		printf("could not delete as key does not exist \n");
-		return;
+		string s(1, (char)240);
+		string response = s + "Delete key not found";
+		sem_post(&w);
+		return response;
 	}
-	// write(STDOUT_FILENO,"the find is not null \n",22);
+	// write(STDOUT_FILENO,"the finding is not null \n",22);
 	char filename2[10];
-	strcpy(filename2,find->filename);
+	strcpy(filename2,finding->filename);
 	int n=open(strcat(filename2,".txt"),O_WRONLY);
 	// write(STDOUT_FILENO,"test \n",6);
-	lseek(n,find->lineno-1,SEEK_SET);
+	lseek(n,finding->lineno-1,SEEK_SET);
 	// write(STDOUT_FILENO,"test \n",6);
 	write(n,"a",1);
 	// write(STDOUT_FILENO,"test \n",6);
 	close(n);
 	// write(STDOUT_FILENO,"test \n",6);
 	// write(STDOUT_FILENO,"the file name i shoud be delted",31);
-	// write(STDOUT_FILENO,find->filename,5);
+	// write(STDOUT_FILENO,finding->filename,5);
 	// write(STDOUT_FILENO,"\n",1);
-	struct n2 *tp=checkfile(h2,find->filename);
+	struct n2 *tp=checkfile(h2,finding->filename);
 	// write(STDOUT_FILENO,"the file name i shoud be delted",31);
-	// write(STDOUT_FILENO,find->filename,1);
+	// write(STDOUT_FILENO,finding->filename,1);
 	// write(STDOUT_FILENO,"\n",1);
 	if(tp==NULL){
 		printf("the checkfile has given NULL");
-		return;
+		string s(1, (char)240);
+		string response = s + "Delete Failed";
+		sem_post(&w);
+
+		return response;
 	}
 	// write(STDOUT_FILENO,"test \n",6);
 	tp->nooffreeline=tp->nooffreeline-1;
 	// write(STDOUT_FILENO,"test \n",6);
-	free(find);
-	find=NULL;
-	
-
-
+	free(finding);
+	finding=NULL;
+	// printf("del function completed\n");
+	string s(1, (char)200);
+	string response = s + "Delete Successful";
+		sem_post(&w);
+
+	return response;
 }
 
-
-
-
-
-
-
 void pp(struct n1*r){
 	if(r==NULL){
 		return;
 	}
     
     pp(r->p1);
-    printf("%s\n",r->key);
+    // printf("%s\n",r->key);
 	
     pp(r->p2);
 }
@@ -737,7 +802,7 @@ void pp2(struct n1*r){
 	if(r==NULL){
 		return;
 	}
-        printf("%s\n",r->key);
+        // printf("%s\n",r->key);
 	
     pp2(r->p1);
 
@@ -746,6 +811,11 @@ void pp2(struct n1*r){
 
 
 
+// int main()
+// {
+// 	printf("Saikumar\n");
+// 	return 0;
+// }