zfs_arc: support for zfsonlinux

fix alocation schemes so the plugin actually works
 - specify type llist_t kstat_t, so we can easily pass in our parsed data
 - read the file into one chunk of memory so we have the values available
 - count the number of lines to allocate the long pointer array
 - parse the buffer line by line.

diff --git a/src/zfs_arc.c b/src/zfs_arc.c
index 4190a71..ebfc54b 100644 (file)
--- a/src/zfs_arc.c
+++ b/src/zfs_arc.c
@@ -37,12 +37,9 @@
 #include "utils_llist.h"
 #define ZOL_ARCSTATS_FILE "/proc/spl/kstat/zfs/arcstats"
 
-#if !defined(kstat_t)
-typedef void kstat_t;
-static llist_t *zfs_stats = NULL;
-#endif
+typedef        llist_t kstat_t;
 
-static long long get_zfs_value(kstat_t *dummy __attribute__((unused)),
+static long long get_zfs_value(kstat_t *zfs_stats  __attribute__((unused)),
                char *name)
 {
        llentry_t *e;
@@ -174,66 +171,70 @@ static int za_read (void)
        kstat_t  *ksp   = NULL;
 
 #if KERNEL_LINUX
-       FILE *fh;
-
-       char buf[1024];
+       long long int *llvalues = NULL;
+       char FileContents[1024 * 10];
        char *fields[3];
        int numfields;
+       ssize_t len;
 
-       if ((fh = fopen (ZOL_ARCSTATS_FILE, "r")) == NULL)
-       {
-               char errbuf[1024];
-               ERROR ("zfs_arc plugin: `fopen (%s)' failed: %s",
-                       ZOL_ARCSTATS_FILE,
-                       sstrerror (errno, errbuf, sizeof (errbuf)));
-               return (-1);
-       }
-
-       zfs_stats = llist_create ();
-       if (zfs_stats == NULL)
+       ksp = llist_create ();
+       if (ksp == NULL)
        {
                ERROR ("zfs_arc plugin: `llist_create' failed.");
-               fclose (fh);
                return (-1);
        }
 
-       while (fgets (buf, 1024, fh) != NULL)
+       len = read_file_contents (ZOL_ARCSTATS_FILE, FileContents, sizeof(FileContents));
+       if (len > 1)
        {
-               numfields = strsplit (buf, fields, 4);
-               if (numfields != 3)
-                       continue;
-
-               char *llkey;
-               long long int llvalue;
-
-               llkey = strdup (fields[0]);
-               if (llkey == NULL) {
-                       char errbuf[1024];
-                       ERROR ("zfs_arc plugin: `strdup' failed: %s",
-                               sstrerror (errno, errbuf, sizeof (errbuf)));
-                       continue;
-               }
 
-               llvalue = atoll (fields[2]);
+               int i=0;
+               char *pnl = FileContents;
+               char *pnnl;
+
+               FileContents[len] = '\0';
 
-               llentry_t *e;
-               e = llentry_create (llkey, (void *)llvalue);
-               if (e == NULL)
+               while (pnl != NULL)
                {
-                       ERROR ("zfs_arc plugin: `llentry_create' failed.");
-                       free (llkey);
-                       continue;
+                       pnl = strchr(pnl, '\n');
+                       i++;
+                       if (pnl && (*pnl != '\0'))
+                               pnl++;
                }
 
-               free (llkey);
-
-               llist_append (zfs_stats, e);
-       }
-
-       if (fclose (fh))
-       {
-               char errbuf[1024];
-               WARNING ("zfs_arc: `fclose' failed: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
+               if (i > 0)
+               {
+                       llentry_t *e;
+                       llvalues = malloc(sizeof(long long int) * i);
+                       i = 0;
+
+                       pnl = FileContents;
+                       while (pnl != NULL)
+                       {
+                               pnnl = strchr(pnl, '\n');
+                               if (pnnl != NULL)
+                                       *pnnl = '\0';
+                               
+                               numfields = strsplit (pnl, fields, 4);
+                               if (numfields == 3)
+                               {
+                                       llvalues[i] = atoll (fields[2]);
+
+                                       e = llentry_create (fields[0], &llvalues[i]);
+                                       if (e == NULL)
+                                       {
+                                               ERROR ("zfs_arc plugin: `llentry_create' failed.");
+                                       }
+                                       else
+                                       {
+                                               llist_append (ksp, e);
+                                       }
+                               }
+                               pnl = pnnl;
+                               if (pnl != NULL)
+                                       pnl ++;
+                       }
+               }
        }
 
 #elif !defined(__FreeBSD__) // Solaris
@@ -291,9 +292,14 @@ static int za_read (void)
        za_submit ("io_octets", "L2", l2_io, /* num values = */ 2);
 
 #if defined(KERNEL_LINUX)
-       if (zfs_stats != NULL)
+       if (llvalues != NULL)
+       {
+               free(llvalues);
+       }
+       if (ksp != NULL)
        {
-               llist_destroy (zfs_stats);
+          
+               llist_destroy (ksp);
        }
 #endif