lnstat: review lnstat_update()

Instead of calling rewind() and fgets() before every call to
scan_lines(), move them into scan_lines() itself.

This should also fix compat mode, as before the second call to
scan_lines() the first line was skipped unconditionally.

Signed-off-by: Phil Sutter <phil@nwl.cc>

diff --git a/misc/lnstat_util.c b/misc/lnstat_util.c
index 6dde7c49432714431157df06d32e8d56bc5d9433..433e992976eac630c1858f7c1040aaa8c7cee633 100644 (file)
--- a/misc/lnstat_util.c
+++ b/misc/lnstat_util.c
@@ -38,18 +38,22 @@
 /* Read (and summarize for SMP) the different stats vars. */
 static int scan_lines(struct lnstat_file *lf, int i)
 {
+       char buf[FGETS_BUF_SIZE];
        int j, num_lines = 0;
 
        for (j = 0; j < lf->num_fields; j++)
                lf->fields[j].values[i] = 0;
 
-       while(!feof(lf->fp)) {
-               char buf[FGETS_BUF_SIZE];
+       rewind(lf->fp);
+       /* skip first line */
+       if (!lf->compat && !fgets(buf, sizeof(buf)-1, lf->fp))
+               return -1;
+
+       while(!feof(lf->fp) && fgets(buf, sizeof(buf)-1, lf->fp)) {
                char *ptr = buf;
 
                num_lines++;
 
-               fgets(buf, sizeof(buf)-1, lf->fp);
                gettimeofday(&lf->last_read, NULL);
 
                for (j = 0; j < lf->num_fields; j++) {
@@ -81,7 +85,6 @@ static int time_after(struct timeval *last,
 int lnstat_update(struct lnstat_file *lnstat_files)
 {
        struct lnstat_file *lf;
-       char buf[FGETS_BUF_SIZE];
        struct timeval tv;
 
        gettimeofday(&tv, NULL);
@@ -91,11 +94,6 @@ int lnstat_update(struct lnstat_file *lnstat_files)
                        int i;
                        struct lnstat_field *lfi;
 
-                       rewind(lf->fp);
-                       if (!lf->compat) {
-                               /* skip first line */
-                               fgets(buf, sizeof(buf)-1, lf->fp);
-                       }
                        scan_lines(lf, 1);
 
                        for (i = 0, lfi = &lf->fields[i];
@@ -107,8 +105,6 @@ int lnstat_update(struct lnstat_file *lnstat_files)
                                                        / lf->interval.tv_sec;
                        }
 
-                       rewind(lf->fp);
-                       fgets(buf, sizeof(buf)-1, lf->fp);
                        scan_lines(lf, 0);
                }
        }