SVG: Handle dynamically (un)registered network interfaces (2)

Commit f5d9bce dealt with network interfaces that can be dynamically
registered or unregistered in /proc/net/dev. But it assumed that network
interfaces appear always at the same position in the /proc/net/dev file.
As this is not necessarily the case, this patch makes sure that we
update the right graph corresponding to the same network interface.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>

diff --git a/sa.h b/sa.h
index c62a38f1482c72cbec18e9fd22f279f9aa8b6c45..21a5d89bfa8e46f6ab81e2b44b777c5cefb6c7e1 100644 (file)
--- a/sa.h
+++ b/sa.h
@@ -904,6 +904,8 @@ struct report_format {
 #define SVG_LINE_GRAPH 1
 #define SVG_BAR_GRAPH  2
 
+#define MAYBE  0x80
+
 /*
  ***************************************************************************
  * Macro functions definitions.

diff --git a/svg_stats.c b/svg_stats.c
index b01e5ae4c3955eaf237d92023df100d9470a3245..2409b30198a2a1aeb17631a708a121ae700e8e39 100644 (file)
--- a/svg_stats.c
+++ b/svg_stats.c
@@ -796,7 +796,7 @@ __print_funct_t svg_print_net_dev_stats(struct activity *a, int curr, int action
        static int *outsize;
        char *item_name;
        double rxkb, txkb, ifutil;
-       int i, j, pos, restart, *unregistered;
+       int i, j, k, pos, restart, *unregistered;
 
        if (action & F_BEGIN) {
                /*
@@ -812,40 +812,65 @@ __print_funct_t svg_print_net_dev_stats(struct activity *a, int curr, int action
 
        if (action & F_MAIN) {
                restart = svg_p->restart;
+               /*
+                * Mark previously registered interfaces as now
+                * possibly unregistered for all graphs.
+                */
+               for (k = 0; k < a->nr; k++) {
+                       unregistered = outsize + k * 9 + 8;
+                       if (*unregistered == FALSE) {
+                               *unregistered = MAYBE;
+                       }
+               }
 
+               /* For each network interfaces structure */
                for (i = 0; i < a->nr; i++) {
-                       pos = i * 9;
-                       unregistered = outsize + pos + 8;
-                       item_name = *(out + pos + 8);
                        sndc = (struct stats_net_dev *) ((char *) a->buf[curr] + i * a->msize);
-
-                       if (!strcmp(sndc->interface, "")) {
-                               /*
-                                * Current interface non existent. Maybe this
-                                * interface will be dynamically registered later,
-                                * or it has been unregistered. So mark it as unregistered.
-                                */
-                               *unregistered = TRUE;
+                       if (!strcmp(sndc->interface, ""))
+                               /* Empty structure: Ignore it */
                                continue;
+
+                       /* Look for corresponding graph */
+                       for (k = 0; k < a->nr; k++) {
+                               item_name = *(out + k * 9 + 8);
+                               if (!strcmp(sndc->interface, item_name))
+                                       /* Graph found! */
+                                       break;
                        }
+                       if (k == a->nr) {
+                               /* Graph not found: Look for first free entry */
+                               for (k = 0; k < a->nr; k++) {
+                                       item_name = *(out + k * 9 + 8);
+                                       if (!strcmp(item_name, ""))
+                                               break;
+                               }
+                               if (k == a->nr)
+                                       /* No free graph entry: Graph for this item won't be drawn */
+                                       continue;
+                       }
+
+                       pos = k * 9;
+                       unregistered = outsize + pos + 8;
 
                        j = check_net_dev_reg(a, curr, !curr, i);
                        sndp = (struct stats_net_dev *) ((char *) a->buf[!curr] + j * a->msize);
 
                        /*
-                        * Current interface was marked as previously unregistered.
-                        * So set restart variable to TRUE so that the graph will be
-                        * discontinuous, then mark current interface as now registered.
+                        * If current interface was marked as previously unregistered,
+                        * then set restart variable to TRUE so that the graph will be
+                        * discontinuous, and mark it as now registered.
                         */
                        if (*unregistered == TRUE) {
                                restart = TRUE;
-                               *unregistered = FALSE;
                        }
-                       if (!**(out + pos + 7)) {
+                       *unregistered = FALSE;
+
+                       if (!item_name[0]) {
                                /* Save network interface name (if not already done) */
                                strncpy(item_name, sndc->interface, CHUNKSIZE);
                                item_name[CHUNKSIZE - 1] = '\0';
                        }
+
                        /* Check for min/max values */
                        save_extrema(7, 0, 0, (void *) sndc, (void *) sndp,
                                     itv, spmin + pos, spmax + pos);
@@ -900,6 +925,14 @@ __print_funct_t svg_print_net_dev_stats(struct activity *a, int curr, int action
                                 ifutil,
                                 out + pos + 7, outsize + pos + 7, restart, svg_p->dt, SVG_BAR_GRAPH);
                }
+
+               /* Mark interfaces not seen here as now unregistered */
+               for (k = 0; k < a->nr; k++) {
+                       unregistered = outsize + k * 9 + 8;
+                       if (*unregistered != FALSE) {
+                               *unregistered = TRUE;
+                       }
+               }
        }
 
        if (action & F_END) {