X-Git-Url: https://gapil.gnulinux.it/gitweb/?p=gapil.git;a=blobdiff_plain;f=sources%2Finotify_monitor.c;fp=sources%2Finotify_monitor.c;h=1acfdb0c65d58b0fa99961ce42b286730958f50c;hp=92391cf39b5133c8ab49435f6c76a1878f0f8dee;hb=96c2ad52857ad188cd53292a581a10c7c24eb0da;hpb=e62b1d15cd14bfe362613091cad4d621c7ffc904

diff --git a/sources/inotify_monitor.c b/sources/inotify_monitor.c
index 92391cf..1acfdb0 100644
--- a/sources/inotify_monitor.c
+++ b/sources/inotify_monitor.c
@@ -27,12 +27,16 @@
  *
  *****************************************************************************/
 #include <sys/types.h>
-#include <sys/inotify.h>
-#include <stdlib.h>        /* C standard library */
-#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/inotify.h> /* Linux inotify interface */
+#include <sys/epoll.h>   /* Linux epoll interface */
+#include <stdlib.h>      /* C standard library */
+#include <unistd.h>      /* Unix standard library */
 #include <errno.h>       /* error definitions and routines */ 
 #include <stdio.h>       /* standard I/O library */
 #include <string.h>      /* string functions */
+#include <fcntl.h>       /* fcntl function */
+#include <sys/ioctl.h>       /* fcntl function */
 
 
 #include "macros.h"
@@ -43,11 +47,12 @@ void printevent(unsigned int mask);
 
 int main(int argc, char *argv[]) 
 {
-    int i, size;
-    int fd, wd;
-    char buffer[128*sizeof(struct inotify_event)];
+    int i, size, nread;
+    int fd, wd, epfd;
+    char buffer[1024 + sizeof(struct inotify_event)];
     unsigned int mask=0;
     struct inotify_event * event;
+    struct epoll_event epev;
     /*
      * Input section: decode command line parameters 
      * Use getopt function
@@ -95,34 +100,70 @@ int main(int argc, char *argv[])
 	printf("Wrong number of arguments %d\n", argc - optind);
         usage();
     }
+    /* initializa epoll */
+    epfd = epoll_create(5);
+    if (epfd < 0)
+        perror("Failing on epoll_create");
+
     /* initalialize inotify */
-    fd = inotify_init ();
+    fd = inotify_init();
     if (fd < 0)
         perror("Failing on inotify_init");
-
+    if (fcntl(fd, F_SETFL, O_NONBLOCK)) 
+	perror("Cannot set noblocking I/O on inotify fd");
+    
     /* add watch */
     wd = inotify_add_watch(fd, argv[optind], mask);
     if ( wd <= 0) {
 	printf("Failing to add watched file %s, mask %i; %s\n", 
 	      argv[optind], mask, strerror(errno));
 	exit(-1);
-    }    
+    }
+    
+    /* add inotify fd to epoll */
+    epev.data.fd = fd;
+    epev.events = EPOLLIN;
+    if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &epev))
+        perror("Failing on epoll_ctl");
+
     /* 
      * Main Loop: read events and print them
      */
     while (1) {
-	size = read(fd, buffer, sizeof(buffer));
+	if (epoll_wait(epfd, &epev, 1, -1) < 0 )
+	    perror("error on epoll_wait");
+	
+	if (epev.data.fd != fd) 
+	    printf("something wrong, epoll activity on %i instead of %i\n",
+		   epev.data.fd, fd);
 	
-	event = (struct inotify_event *) buffer;
-        if (wd != event->wd) {
-	    printf("Error, getting different watch descriptor, %i and %i\n",
-		   wd, event->wd); 
+	if (ioctl(fd, FIONREAD, &size))
+	    perror("error on getting inotify event size");
+
+	if (size > sizeof(buffer)) {
+	    printf("Too many %i data to read, something wrong\n", size);
 	    exit(1);
 	}
-	printf("Observed event on %s\n", argv[optind-1+event->wd]);
-	if (event->name != NULL)
-	    printf("On file %s\n", event->name);
-	printevent(event->mask);
+	i = 0;
+	while (i < size) {
+	    nread = read(fd, buffer, size);
+	    if (nread < 0) {
+		perror("error reading inotify data");
+		exit(1);
+	    }
+	    i += nread; 
+
+	    event = (struct inotify_event *) buffer;
+	    if (wd != event->wd) {
+		printf("Getting different watch descriptor, %i and %i\n",
+		       wd, event->wd); 
+		exit(1);
+	    }
+	    printf("Observed event on %s\n", argv[optind-1+event->wd]);
+	    if (event->name != NULL)
+		printf("On file %s\n", event->name);
+	    printevent(event->mask);
+	}
     }
     return 0;