From 029edc22fa4ba93f5849d7c812ad2f3509a81287 Mon Sep 17 00:00:00 2001
From: elvis <elvilio98@gmail.com>
Date: Sat, 9 Apr 2022 01:11:46 +0200
Subject: [PATCH] added function lockFile

---
 lib/threadpool/apiFile.c   | 62 ++++++++++++++++++++++++++++++++++++++
 lib/threadpool/fileQueue.c |  3 +-
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/lib/threadpool/apiFile.c b/lib/threadpool/apiFile.c
index fff79d7..cabdc5b 100644
--- a/lib/threadpool/apiFile.c
+++ b/lib/threadpool/apiFile.c
@@ -237,6 +237,9 @@ void openFile(char *filepath, int flags, queueT *q, long fd_c, taglia_t *taglia)
 	sendMessage(MEOK, fd_c, taglia, tmp_buf);
 	return;
     }
+
+    // codice non raggiungibile
+    return;
 }
 
 
@@ -296,6 +299,7 @@ void writeFile(char *filepath, size_t size, queueT *q, long fd_c, taglia_t *tagl
 	return;
     }
 
+    // cerco il file
     fileT *f = NULL;
     f = find(q, filepath);
     if(!f) { // file is not present
@@ -418,6 +422,64 @@ void writeFile(char *filepath, size_t size, queueT *q, long fd_c, taglia_t *tagl
 
 
 void lockFile(char *filepath, queueT *q, long fd_c, taglia_t *taglia, pthread_mutex_t *lock, waiting_t **waiting) {
+    // messaggio da scrivere sul logfile
+    char tmp_buf[2048];
+    int n = 0;
+    size_t m = sizeof(tmp_buf);
+
+    if(!filepath || !q || !taglia || !lock || !waiting) {
+	n += snprintf(tmp_buf+n, m-n, "Client %ld ha richiesto una lockFile sul file \"%s\" e' terminata con errore.\n", fd_c, filepath);
+	errno = EINVAL;
+	serror(MESY, fd_c, taglia, tmp_buf);
+	return;
+    }
+
+    // cerco il file da impostare in modalita' locked
+    fileT *f = NULL;
+    f = find(q, filepath);
+    if(!f) { // file is not present
+	n += snprintf(tmp_buf+n, m-n, "Client %ld ha richiesto una lockFile sul file \"%s\" ma risulta assente.\n", fd_c, filepath);
+	errno = ENOENT;
+	serror(MENT, fd_c, taglia, tmp_buf);
+	destroyFile(f);
+	return;
+    }
+
+    // provo a prendere la lock
+    if (openFileInQueue(q, filepath, 1, fd_c) == -1) {
+	// non siamo riusciti a prendere la lock al file, quindi aspettiamo che
+	// venga rilasciata mettendoci in attesa nella waiting list
+	if (errno == EPERM) {
+	    if (pthread_mutex_lock(lock) == -1) { // begin ME
+		perror("lock");
+		destroyFile(f);
+		return;
+	    }
+
+	    if (addWaiting(waiting, filepath, fd_c) == -1) {
+		perror("addWaiting");
+		pthread_mutex_unlock(lock);
+		destroyFile(f);
+		return;
+	    }
+
+	    if (pthread_mutex_unlock(lock) == -1) { // end ME
+		perror("unlock");
+	    }
+	    destroyFile(f);
+	    return;
+	}
+
+	n += snprintf(tmp_buf+n, m-n, "Client %ld ha richiesto una lockFile sul file \"%s\" e' terminata con errore.\n", fd_c, filepath);
+	errno = ENOLCK;
+	serror(MESE, fd_c, taglia, tmp_buf);
+	destroyFile(f);
+	return;
+    }
+
+    n += snprintf(tmp_buf+n, m-n, "Client %ld ha richiesto una lockFile sul file \"%s\" e' terminata con successo\n", fd_c, filepath);
+    sendMessage(MEOK, fd_c, taglia, tmp_buf);
+    destroyFile(f);
     return;
 }
 
diff --git a/lib/threadpool/fileQueue.c b/lib/threadpool/fileQueue.c
index a87f7ee..82890ca 100644
--- a/lib/threadpool/fileQueue.c
+++ b/lib/threadpool/fileQueue.c
@@ -460,7 +460,8 @@ int openFileInQueue(queueT *q, char *filepath, int O_LOCK, int owner) {
 	goto _end_open_file_queue;
     }
 
-    if((tmp->data)->O_LOCK == 1 && (tmp->data)->owner != owner) { // lock non del owner
+    // lock non del owner
+    if((tmp->data)->O_LOCK == 1 && (tmp->data)->owner != owner) {
 	errno = EPERM;
 	goto _end_open_file_queue;
     }