bootchart: kill a bunch of global variables

This code is in a confusingly bad shape. Kill a bunch of global variables
and pass needed variables around in function calls.

1 files changed, 330 insertions, 322 deletions

diff --git a/src/bootchart/svg.c b/src/bootchart/svg.c
index b031090d2f..c89ef8ed5c 100644
--- a/src/bootchart/svg.c
+++ b/src/bootchart/svg.c
@@ -44,10 +44,6 @@
 #define kb_to_graph(m) ((m) * arg_scale_y * 0.0001)
 #define to_color(n) (192.0 - ((n) * 192.0))
 
-static char str[8092];
-
-#define svg(a...) do { snprintf(str, 8092, ## a); fputs(str, of); fflush(of); } while (0)
-
 static const char * const colorwheel[12] = {
         "rgb(255,32,32)",  // red
         "rgb(32,192,192)", // cyan
@@ -72,9 +68,8 @@ static double ksize = 0;
 static double esize = 0;
 static struct list_sample_data *sampledata;
 static struct list_sample_data *prev_sampledata;
-extern struct list_sample_data *head;
 
-static void svg_header(void) {
+static void svg_header(FILE *of, struct list_sample_data *head, double graph_start) {
         double w;
         double h;
         struct list_sample_data *sampledata_last;
@@ -97,60 +92,59 @@ static void svg_header(void) {
             + (arg_pss ? (100.0 * arg_scale_y) + (arg_scale_y * 7.0) : 0.0) /* pss estimate */
             + psize + ksize + esize;
 
-        svg("<?xml version=\"1.0\" standalone=\"no\"?>\n");
-        svg("<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" ");
-        svg("\"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n");
+        fprintf(of, "<?xml version=\"1.0\" standalone=\"no\"?>\n");
+        fprintf(of, "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" ");
+        fprintf(of, "\"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n");
 
-        //svg("<g transform=\"translate(10,%d)\">\n", 1000 + 150 + (pcount * 20));
-        svg("<svg width=\"%.0fpx\" height=\"%.0fpx\" version=\"1.1\" ",
-            w, h);
-        svg("xmlns=\"http://www.w3.org/2000/svg\">\n\n");
+        //fprintf(of, "<g transform=\"translate(10,%d)\">\n", 1000 + 150 + (pcount * 20));
+        fprintf(of, "<svg width=\"%.0fpx\" height=\"%.0fpx\" version=\"1.1\" ", w, h);
+        fprintf(of, "xmlns=\"http://www.w3.org/2000/svg\">\n\n");
 
         /* write some basic info as a comment, including some help */
-        svg("<!-- This file is a bootchart SVG file. It is best rendered in a browser -->\n");
-        svg("<!-- such as Chrome, Chromium, or Firefox. Other applications that       -->\n");
-        svg("<!-- render these files properly but more slowly are ImageMagick, gimp,  -->\n");
-        svg("<!-- inkscape, etc. To display the files on your system, just point      -->\n");
-        svg("<!-- your browser to file:///run/log/ and click. This bootchart was      -->\n\n");
-
-        svg("<!-- generated by bootchart version %s, running with options:  -->\n", VERSION);
-        svg("<!-- hz=\"%f\" n=\"%d\" -->\n", arg_hz, arg_samples_len);
-        svg("<!-- x=\"%f\" y=\"%f\" -->\n", arg_scale_x, arg_scale_y);
-        svg("<!-- rel=\"%d\" f=\"%d\" -->\n", arg_relative, arg_filter);
-        svg("<!-- p=\"%d\" e=\"%d\" -->\n", arg_pss, arg_entropy);
-        svg("<!-- o=\"%s\" i=\"%s\" -->\n\n", arg_output_path, arg_init_path);
+        fprintf(of, "<!-- This file is a bootchart SVG file. It is best rendered in a browser -->\n");
+        fprintf(of, "<!-- such as Chrome, Chromium, or Firefox. Other applications that       -->\n");
+        fprintf(of, "<!-- render these files properly but more slowly are ImageMagick, gimp,  -->\n");
+        fprintf(of, "<!-- inkscape, etc. To display the files on your system, just point      -->\n");
+        fprintf(of, "<!-- your browser to file:///run/log/ and click. This bootchart was      -->\n\n");
+
+        fprintf(of, "<!-- generated by bootchart version %s, running with options:  -->\n", VERSION);
+        fprintf(of, "<!-- hz=\"%f\" n=\"%d\" -->\n", arg_hz, arg_samples_len);
+        fprintf(of, "<!-- x=\"%f\" y=\"%f\" -->\n", arg_scale_x, arg_scale_y);
+        fprintf(of, "<!-- rel=\"%d\" f=\"%d\" -->\n", arg_relative, arg_filter);
+        fprintf(of, "<!-- p=\"%d\" e=\"%d\" -->\n", arg_pss, arg_entropy);
+        fprintf(of, "<!-- o=\"%s\" i=\"%s\" -->\n\n", arg_output_path, arg_init_path);
 
         /* style sheet */
-        svg("<defs>\n  <style type=\"text/css\">\n    <![CDATA[\n");
-
-        svg("      rect       { stroke-width: 1; }\n");
-        svg("      rect.bg    { fill: rgb(255,255,255); }\n");
-        svg("      rect.cpu   { fill: rgb(64,64,240); stroke-width: 0; fill-opacity: 0.7; }\n");
-        svg("      rect.wait  { fill: rgb(240,240,0); stroke-width: 0; fill-opacity: 0.7; }\n");
-        svg("      rect.bi    { fill: rgb(240,128,128); stroke-width: 0; fill-opacity: 0.7; }\n");
-        svg("      rect.bo    { fill: rgb(192,64,64); stroke-width: 0; fill-opacity: 0.7; }\n");
-        svg("      rect.ps    { fill: rgb(192,192,192); stroke: rgb(128,128,128); fill-opacity: 0.7; }\n");
-        svg("      rect.krnl  { fill: rgb(240,240,0); stroke: rgb(128,128,128); fill-opacity: 0.7; }\n");
-        svg("      rect.box   { fill: rgb(240,240,240); stroke: rgb(192,192,192); }\n");
-        svg("      rect.clrw  { stroke-width: 0; fill-opacity: 0.7;}\n");
-        svg("      line       { stroke: rgb(64,64,64); stroke-width: 1; }\n");
-        svg("//    line.sec1  { }\n");
-        svg("      line.sec5  { stroke-width: 2; }\n");
-        svg("      line.sec01 { stroke: rgb(224,224,224); stroke-width: 1; }\n");
-        svg("      line.dot   { stroke-dasharray: 2 4; }\n");
-        svg("      line.idle  { stroke: rgb(64,64,64); stroke-dasharray: 10 6; stroke-opacity: 0.7; }\n");
-
-        svg("      .run       { font-size: 8; font-style: italic; }\n");
-        svg("      text       { font-family: Verdana, Helvetica; font-size: 10; }\n");
-        svg("      text.sec   { font-size: 8; }\n");
-        svg("      text.t1    { font-size: 24; }\n");
-        svg("      text.t2    { font-size: 12; }\n");
-        svg("      text.idle  { font-size: 18; }\n");
-
-        svg("    ]]>\n   </style>\n</defs>\n\n");
+        fprintf(of, "<defs>\n  <style type=\"text/css\">\n    <![CDATA[\n");
+
+        fprintf(of, "      rect       { stroke-width: 1; }\n");
+        fprintf(of, "      rect.bg    { fill: rgb(255,255,255); }\n");
+        fprintf(of, "      rect.cpu   { fill: rgb(64,64,240); stroke-width: 0; fill-opacity: 0.7; }\n");
+        fprintf(of, "      rect.wait  { fill: rgb(240,240,0); stroke-width: 0; fill-opacity: 0.7; }\n");
+        fprintf(of, "      rect.bi    { fill: rgb(240,128,128); stroke-width: 0; fill-opacity: 0.7; }\n");
+        fprintf(of, "      rect.bo    { fill: rgb(192,64,64); stroke-width: 0; fill-opacity: 0.7; }\n");
+        fprintf(of, "      rect.ps    { fill: rgb(192,192,192); stroke: rgb(128,128,128); fill-opacity: 0.7; }\n");
+        fprintf(of, "      rect.krnl  { fill: rgb(240,240,0); stroke: rgb(128,128,128); fill-opacity: 0.7; }\n");
+        fprintf(of, "      rect.box   { fill: rgb(240,240,240); stroke: rgb(192,192,192); }\n");
+        fprintf(of, "      rect.clrw  { stroke-width: 0; fill-opacity: 0.7;}\n");
+        fprintf(of, "      line       { stroke: rgb(64,64,64); stroke-width: 1; }\n");
+        fprintf(of, "//    line.sec1  { }\n");
+        fprintf(of, "      line.sec5  { stroke-width: 2; }\n");
+        fprintf(of, "      line.sec01 { stroke: rgb(224,224,224); stroke-width: 1; }\n");
+        fprintf(of, "      line.dot   { stroke-dasharray: 2 4; }\n");
+        fprintf(of, "      line.idle  { stroke: rgb(64,64,64); stroke-dasharray: 10 6; stroke-opacity: 0.7; }\n");
+
+        fprintf(of, "      .run       { font-size: 8; font-style: italic; }\n");
+        fprintf(of, "      text       { font-family: Verdana, Helvetica; font-size: 10; }\n");
+        fprintf(of, "      text.sec   { font-size: 8; }\n");
+        fprintf(of, "      text.t1    { font-size: 24; }\n");
+        fprintf(of, "      text.t2    { font-size: 12; }\n");
+        fprintf(of, "      text.idle  { font-size: 18; }\n");
+
+        fprintf(of, "    ]]>\n   </style>\n</defs>\n\n");
 }
 
-static int svg_title(const char *build) {
+static int svg_title(FILE *of, const char *build, int pscount, double log_start, int overrun) {
         _cleanup_free_ char *cmdline = NULL;
         _cleanup_free_ char *model = NULL;
         _cleanup_free_ char *buf = NULL;
@@ -179,10 +173,8 @@ static int svg_title(const char *build) {
                 snprintf(filename, sizeof(filename), "/sys/block/%s/device/model", rootbdev);
 
                 r = read_one_line_file(filename, &model);
-                if (r < 0) {
-                        log_error("Error reading disk model for %s: %m\n", rootbdev);
-                        return r;
-                }
+                if (r < 0)
+                        log_warning("Error reading disk model for %s: %m\n", rootbdev);
         }
 
         /* various utsname parameters */
@@ -215,33 +207,30 @@ static int svg_title(const char *build) {
         if (c)
                 *c = '\0';
 
-        svg("<text class=\"t1\" x=\"0\" y=\"30\">Bootchart for %s - %s</text>\n",
-            uts.nodename, date);
-        svg("<text class=\"t2\" x=\"20\" y=\"50\">System: %s %s %s %s</text>\n",
-            uts.sysname, uts.release, uts.version, uts.machine);
-        svg("<text class=\"t2\" x=\"20\" y=\"65\">CPU: %s</text>\n",
-            cpu);
-        svg("<text class=\"t2\" x=\"20\" y=\"80\">Disk: %s</text>\n",
-            model);
-        svg("<text class=\"t2\" x=\"20\" y=\"95\">Boot options: %s</text>\n",
-            cmdline);
-        svg("<text class=\"t2\" x=\"20\" y=\"110\">Build: %s</text>\n",
-            build);
-        svg("<text class=\"t2\" x=\"20\" y=\"125\">Log start time: %.03fs</text>\n", log_start);
-        svg("<text class=\"t2\" x=\"20\" y=\"140\">Idle time: ");
+        fprintf(of, "<text class=\"t1\" x=\"0\" y=\"30\">Bootchart for %s - %s</text>\n",
+                uts.nodename, date);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"50\">System: %s %s %s %s</text>\n",
+                uts.sysname, uts.release, uts.version, uts.machine);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"65\">CPU: %s</text>\n", cpu);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"80\">Disk: %s</text>\n", model);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"95\">Boot options: %s</text>\n", cmdline);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"110\">Build: %s</text>\n", build);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"125\">Log start time: %.03fs</text>\n", log_start);
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"140\">Idle time: ");
 
         if (idletime >= 0.0)
-                svg("%.03fs", idletime);
+                fprintf(of, "%.03fs", idletime);
         else
-                svg("Not detected");
-        svg("</text>\n");
-        svg("<text class=\"sec\" x=\"20\" y=\"155\">Graph data: %.03f samples/sec, recorded %i total, dropped %i samples, %i processes, %i filtered</text>\n",
-            arg_hz, arg_samples_len, overrun, pscount, pfiltered);
+                fprintf(of, "Not detected");
+
+        fprintf(of, "</text>\n");
+        fprintf(of, "<text class=\"sec\" x=\"20\" y=\"155\">Graph data: %.03f samples/sec, recorded %i total, dropped %i samples, %i processes, %i filtered</text>\n",
+                arg_hz, arg_samples_len, overrun, pscount, pfiltered);
 
         return 0;
 }
 
-static void svg_graph_box(int height) {
+static void svg_graph_box(FILE *of, struct list_sample_data *head, int height, double graph_start) {
         double d = 0.0;
         int i = 0;
         double finalsample = 0.0;
@@ -255,36 +244,35 @@ static void svg_graph_box(int height) {
         finalsample = sampledata_last->sampletime;
 
         /* outside box, fill */
-        svg("<rect class=\"box\" x=\"%.03f\" y=\"0\" width=\"%.03f\" height=\"%.03f\" />\n",
-            time_to_graph(0.0),
-            time_to_graph(finalsample - graph_start),
-            ps_to_graph(height));
+        fprintf(of, "<rect class=\"box\" x=\"%.03f\" y=\"0\" width=\"%.03f\" height=\"%.03f\" />\n",
+                time_to_graph(0.0),
+                time_to_graph(finalsample - graph_start),
+                ps_to_graph(height));
 
         for (d = graph_start; d <= finalsample;
              d += (arg_scale_x < 2.0 ? 60.0 : arg_scale_x < 10.0 ? 1.0 : 0.1)) {
                 /* lines for each second */
                 if (i % 50 == 0)
-                        svg("  <line class=\"sec5\" x1=\"%.03f\" y1=\"0\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                            time_to_graph(d - graph_start),
-                            time_to_graph(d - graph_start),
-                            ps_to_graph(height));
+                        fprintf(of, "  <line class=\"sec5\" x1=\"%.03f\" y1=\"0\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                time_to_graph(d - graph_start),
+                                time_to_graph(d - graph_start),
+                                ps_to_graph(height));
                 else if (i % 10 == 0)
-                        svg("  <line class=\"sec1\" x1=\"%.03f\" y1=\"0\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                            time_to_graph(d - graph_start),
-                            time_to_graph(d - graph_start),
-                            ps_to_graph(height));
+                        fprintf(of, "  <line class=\"sec1\" x1=\"%.03f\" y1=\"0\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                time_to_graph(d - graph_start),
+                                time_to_graph(d - graph_start),
+                                ps_to_graph(height));
                 else
-                        svg("  <line class=\"sec01\" x1=\"%.03f\" y1=\"0\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                            time_to_graph(d - graph_start),
-                            time_to_graph(d - graph_start),
-                            ps_to_graph(height));
+                        fprintf(of, "  <line class=\"sec01\" x1=\"%.03f\" y1=\"0\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                time_to_graph(d - graph_start),
+                                time_to_graph(d - graph_start),
+                                ps_to_graph(height));
 
                 /* time label */
                 if (i % 10 == 0)
-                        svg("  <text class=\"sec\" x=\"%.03f\" y=\"%.03f\" >%.01fs</text>\n",
-                            time_to_graph(d - graph_start),
-                            -5.0,
-                            d - graph_start);
+                        fprintf(of, "  <text class=\"sec\" x=\"%.03f\" y=\"%.03f\" >%.01fs</text>\n",
+                                time_to_graph(d - graph_start),
+                                -5.0, d - graph_start);
 
                 i++;
         }
@@ -305,7 +293,10 @@ static char* xml_comment_encode(const char* name) {
         return enc_name;
 }
 
-static void svg_pss_graph(void) {
+static void svg_pss_graph(FILE *of,
+                          struct list_sample_data *head,
+                          struct ps_struct *ps_first,
+                          double graph_start) {
         struct ps_struct *ps;
         int i;
         struct list_sample_data *sampledata_last;
@@ -316,24 +307,24 @@ static void svg_pss_graph(void) {
         }
 
 
-        svg("\n\n<!-- Pss memory size graph -->\n");
+        fprintf(of, "\n\n<!-- Pss memory size graph -->\n");
 
-        svg("\n  <text class=\"t2\" x=\"5\" y=\"-15\">Memory allocation - Pss</text>\n");
+        fprintf(of, "\n  <text class=\"t2\" x=\"5\" y=\"-15\">Memory allocation - Pss</text>\n");
 
         /* vsize 1000 == 1000mb */
-        svg_graph_box(100);
+        svg_graph_box(of, head, 100, graph_start);
         /* draw some hlines for usable memory sizes */
         for (i = 100000; i < 1000000; i += 100000) {
-                svg("  <line class=\"sec01\" x1=\"%.03f\" y1=\"%.0f\" x2=\"%.03f\" y2=\"%.0f\"/>\n",
+                fprintf(of, "  <line class=\"sec01\" x1=\"%.03f\" y1=\"%.0f\" x2=\"%.03f\" y2=\"%.0f\"/>\n",
                         time_to_graph(.0),
                         kb_to_graph(i),
                         time_to_graph(sampledata_last->sampletime - graph_start),
                         kb_to_graph(i));
-                svg("  <text class=\"sec\" x=\"%.03f\" y=\"%.0f\">%dM</text>\n",
-                    time_to_graph(sampledata_last->sampletime - graph_start) + 5,
-                    kb_to_graph(i), (1000000 - i) / 1000);
+                fprintf(of, "  <text class=\"sec\" x=\"%.03f\" y=\"%.0f\">%dM</text>\n",
+                        time_to_graph(sampledata_last->sampletime - graph_start) + 5,
+                        kb_to_graph(i), (1000000 - i) / 1000);
         }
-        svg("\n");
+        fprintf(of, "\n");
 
         /* now plot the graph itself */
         i = 1;
@@ -372,7 +363,7 @@ static void svg_pss_graph(void) {
                                 top += ps->sample->pss;
                 }
 
-                svg("    <rect class=\"clrw\" style=\"fill: %s\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                fprintf(of, "    <rect class=\"clrw\" style=\"fill: %s\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
                     "rgb(64,64,64)",
                     time_to_graph(prev_sampledata->sampletime - graph_start),
                     kb_to_graph(1000000.0 - top),
@@ -396,7 +387,7 @@ static void svg_pss_graph(void) {
                         if (ps->sample->sampledata == sampledata) {
                                 if (ps->sample->pss > (100 * arg_scale_y)) {
                                 top = bottom + ps->sample->pss;
-                                svg("    <rect class=\"clrw\" style=\"fill: %s\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                fprintf(of, "    <rect class=\"clrw\" style=\"fill: %s\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
                                   colorwheel[ps->pid % 12],
                                   time_to_graph(prev_sampledata->sampletime - graph_start),
                                   kb_to_graph(1000000.0 - top),
@@ -412,7 +403,7 @@ static void svg_pss_graph(void) {
                         ps->sample = cross_place;
                         if (ps->sample->pss > (100 * arg_scale_y)) {
                                 top = bottom + ps->sample->pss;
-                                svg("    <rect class=\"clrw\" style=\"fill: %s\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                fprintf(of, "    <rect class=\"clrw\" style=\"fill: %s\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
                                   colorwheel[ps->pid % 12],
                                   time_to_graph(prev_sampledata->sampletime - graph_start),
                                   kb_to_graph(1000000.0 - top),
@@ -479,7 +470,7 @@ static void svg_pss_graph(void) {
                                         top = bottom + ps->sample->pss;
                                         /* draw a label with the process / PID */
                                         if ((i == 1) || (prev_sample->pss <= (100 * arg_scale_y)))
-                                                svg("  <text x=\"%.03f\" y=\"%.03f\"><![CDATA[%s]]> [%i]</text>\n",
+                                                fprintf(of, "  <text x=\"%.03f\" y=\"%.03f\"><![CDATA[%s]]> [%i]</text>\n",
                                                     time_to_graph(sampledata->sampletime - graph_start),
                                                     kb_to_graph(1000000.0 - bottom - ((top -  bottom) / 2)),
                                                     ps->name,
@@ -497,11 +488,10 @@ static void svg_pss_graph(void) {
                                 top = bottom + ps->sample->pss;
                                 /* draw a label with the process / PID */
                                 if ((i == 1) || (prev_sample->pss <= (100 * arg_scale_y)))
-                                        svg("  <text x=\"%.03f\" y=\"%.03f\"><![CDATA[%s]]> [%i]</text>\n",
-                                            time_to_graph(sampledata->sampletime - graph_start),
-                                            kb_to_graph(1000000.0 - bottom - ((top -  bottom) / 2)),
-                                            ps->name,
-                                            ps->pid);
+                                        fprintf(of, "  <text x=\"%.03f\" y=\"%.03f\"><![CDATA[%s]]> [%i]</text>\n",
+                                                time_to_graph(sampledata->sampletime - graph_start),
+                                                kb_to_graph(1000000.0 - bottom - ((top -  bottom) / 2)),
+                                                ps->name, ps->pid);
                                 bottom = top;
                         }
                 }
@@ -509,7 +499,7 @@ static void svg_pss_graph(void) {
         }
 
         /* debug output - full data dump */
-        svg("\n\n<!-- PSS map - csv format -->\n");
+        fprintf(of, "\n\n<!-- PSS map - csv format -->\n");
         ps = ps_first;
         while (ps->next_ps) {
                 _cleanup_free_ char *enc_name = NULL;
@@ -521,19 +511,24 @@ static void svg_pss_graph(void) {
                 if (!enc_name)
                         continue;
 
-                svg("<!-- %s [%d] pss=", enc_name, ps->pid);
+                fprintf(of, "<!-- %s [%d] pss=", enc_name, ps->pid);
 
                 ps->sample = ps->first;
                 while (ps->sample->next) {
                         ps->sample = ps->sample->next;
-                        svg("%d," , ps->sample->pss);
+                        fprintf(of, "%d," , ps->sample->pss);
                 }
-                svg(" -->\n");
+                fprintf(of, " -->\n");
         }
 
 }
 
-static void svg_io_bi_bar(void) {
+static void svg_io_bi_bar(FILE *of,
+                          struct list_sample_data *head,
+                          int n_samples,
+                          double graph_start,
+                          double interval) {
+
         double max = 0.0;
         double range;
         int max_here = 0;
@@ -542,9 +537,8 @@ static void svg_io_bi_bar(void) {
         struct list_sample_data *start_sampledata;
         struct list_sample_data *stop_sampledata;
 
-        svg("<!-- IO utilization graph - In -->\n");
-
-        svg("<text class=\"t2\" x=\"5\" y=\"-15\">IO utilization - read</text>\n");
+        fprintf(of, "<!-- IO utilization graph - In -->\n");
+        fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">IO utilization - read</text>\n");
 
         /*
          * calculate rounding range
@@ -558,7 +552,7 @@ static void svg_io_bi_bar(void) {
                 range = 2.0; /* no smoothing */
 
         /* surrounding box */
-        svg_graph_box(5);
+        svg_graph_box(of, head, 5, graph_start);
 
         /* find the max IO first */
         i = 1;
@@ -569,7 +563,7 @@ static void svg_io_bi_bar(void) {
                 double tot;
 
                 start = MAX(i - ((range / 2) - 1), 0);
-                stop = MIN(i + (range / 2), samples - 1);
+                stop = MIN(i + (range / 2), n_samples - 1);
                 diff = (stop - start);
 
                 start_sampledata = sampledata;
@@ -608,7 +602,7 @@ static void svg_io_bi_bar(void) {
                 double pbi = 0;
 
                 start = MAX(i - ((range / 2) - 1), 0);
-                stop = MIN(i + (range / 2), samples);
+                stop = MIN(i + (range / 2), n_samples);
                 diff = (stop - start);
 
                 start_sampledata = sampledata;
@@ -626,25 +620,29 @@ static void svg_io_bi_bar(void) {
                         pbi = tot / max;
 
                 if (pbi > 0.001)
-                        svg("<rect class=\"bi\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                            time_to_graph(prev_sampledata->sampletime - graph_start),
-                            (arg_scale_y * 5) - (pbi * (arg_scale_y * 5)),
-                            time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
-                            pbi * (arg_scale_y * 5));
+                        fprintf(of, "<rect class=\"bi\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                time_to_graph(prev_sampledata->sampletime - graph_start),
+                                (arg_scale_y * 5) - (pbi * (arg_scale_y * 5)),
+                                time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
+                                pbi * (arg_scale_y * 5));
 
                 /* labels around highest value */
                 if (i == max_here) {
-                        svg("  <text class=\"sec\" x=\"%.03f\" y=\"%.03f\">%0.2fmb/sec</text>\n",
-                            time_to_graph(sampledata->sampletime - graph_start) + 5,
-                            ((arg_scale_y * 5) - (pbi * (arg_scale_y * 5))) + 15,
-                            max / 1024.0 / (interval / 1000000000.0));
+                        fprintf(of, "  <text class=\"sec\" x=\"%.03f\" y=\"%.03f\">%0.2fmb/sec</text>\n",
+                                time_to_graph(sampledata->sampletime - graph_start) + 5,
+                                ((arg_scale_y * 5) - (pbi * (arg_scale_y * 5))) + 15,
+                                max / 1024.0 / (interval / 1000000000.0));
                 }
                 i++;
                 prev_sampledata = sampledata;
         }
 }
 
-static void svg_io_bo_bar(void) {
+static void svg_io_bo_bar(FILE *of,
+                          struct list_sample_data *head,
+                          int n_samples,
+                          double graph_start,
+                          double interval) {
         double max = 0.0;
         double range;
         int max_here = 0;
@@ -653,9 +651,8 @@ static void svg_io_bo_bar(void) {
         struct list_sample_data *start_sampledata;
         struct list_sample_data *stop_sampledata;
 
-        svg("<!-- IO utilization graph - out -->\n");
-
-        svg("<text class=\"t2\" x=\"5\" y=\"-15\">IO utilization - write</text>\n");
+        fprintf(of, "<!-- IO utilization graph - out -->\n");
+        fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">IO utilization - write</text>\n");
 
         /*
          * calculate rounding range
@@ -669,7 +666,7 @@ static void svg_io_bo_bar(void) {
                 range = 2.0; /* no smoothing */
 
         /* surrounding box */
-        svg_graph_box(5);
+        svg_graph_box(of, head, 5, graph_start);
 
         /* find the max IO first */
         i = 0;
@@ -680,7 +677,7 @@ static void svg_io_bo_bar(void) {
                 double tot;
 
                 start = MAX(i - ((range / 2) - 1), 0);
-                stop = MIN(i + (range / 2), samples - 1);
+                stop = MIN(i + (range / 2), n_samples - 1);
                 diff = (stop - start);
 
                 start_sampledata = sampledata;
@@ -717,7 +714,7 @@ static void svg_io_bo_bar(void) {
                 pbo = 0;
 
                 start = MAX(i - ((range / 2) - 1), 0);
-                stop = MIN(i + (range / 2), samples);
+                stop = MIN(i + (range / 2), n_samples);
                 diff = (stop - start);
 
                 start_sampledata = sampledata;
@@ -735,34 +732,34 @@ static void svg_io_bo_bar(void) {
                         pbo = tot / max;
 
                 if (pbo > 0.001)
-                        svg("<rect class=\"bo\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                            time_to_graph(prev_sampledata->sampletime - graph_start),
-                            (arg_scale_y * 5) - (pbo * (arg_scale_y * 5)),
-                            time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
-                            pbo * (arg_scale_y * 5));
+                        fprintf(of, "<rect class=\"bo\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                time_to_graph(prev_sampledata->sampletime - graph_start),
+                                (arg_scale_y * 5) - (pbo * (arg_scale_y * 5)),
+                                time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
+                                pbo * (arg_scale_y * 5));
 
                 /* labels around highest bo value */
                 if (i == max_here) {
-                        svg("  <text class=\"sec\" x=\"%.03f\" y=\"%.03f\">%0.2fmb/sec</text>\n",
-                            time_to_graph(sampledata->sampletime - graph_start) + 5,
-                            ((arg_scale_y * 5) - (pbo * (arg_scale_y * 5))),
-                            max / 1024.0 / (interval / 1000000000.0));
+                        fprintf(of, "  <text class=\"sec\" x=\"%.03f\" y=\"%.03f\">%0.2fmb/sec</text>\n",
+                                time_to_graph(sampledata->sampletime - graph_start) + 5,
+                                ((arg_scale_y * 5) - (pbo * (arg_scale_y * 5))),
+                                max / 1024.0 / (interval / 1000000000.0));
                 }
                 i++;
                 prev_sampledata = sampledata;
         }
 }
 
-static void svg_cpu_bar(int cpu_num) {
+static void svg_cpu_bar(FILE *of, struct list_sample_data *head, int n_cpus, int cpu_num, double graph_start) {
 
-        svg("<!-- CPU utilization graph -->\n");
+        fprintf(of, "<!-- CPU utilization graph -->\n");
 
         if (cpu_num < 0)
-                svg("<text class=\"t2\" x=\"5\" y=\"-15\">CPU[overall] utilization</text>\n");
+                fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">CPU[overall] utilization</text>\n");
         else
-                svg("<text class=\"t2\" x=\"5\" y=\"-15\">CPU[%d] utilization</text>\n", cpu_num);
+                fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">CPU[%d] utilization</text>\n", cpu_num);
         /* surrounding box */
-        svg_graph_box(5);
+        svg_graph_box(of, head, 5, graph_start);
 
         /* bars for each sample, proportional to the CPU util. */
         prev_sampledata = head;
@@ -774,7 +771,7 @@ static void svg_cpu_bar(int cpu_num) {
                 ptrt = trt = 0.0;
 
                 if (cpu_num < 0)
-                        for (c = 0; c < cpus; c++)
+                        for (c = 0; c < n_cpus; c++)
                                 trt += sampledata->runtime[c] - prev_sampledata->runtime[c];
                 else
                         trt = sampledata->runtime[cpu_num] - prev_sampledata->runtime[cpu_num];
@@ -782,7 +779,7 @@ static void svg_cpu_bar(int cpu_num) {
                 trt = trt / 1000000000.0;
 
                 if (cpu_num < 0)
-                        trt = trt / (double)cpus;
+                        trt = trt / (double)n_cpus;
 
                 if (trt > 0.0)
                         ptrt = trt / (sampledata->sampletime - prev_sampledata->sampletime);
@@ -791,27 +788,27 @@ static void svg_cpu_bar(int cpu_num) {
                         ptrt = 1.0;
 
                 if (ptrt > 0.001) {
-                        svg("<rect class=\"cpu\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                            time_to_graph(prev_sampledata->sampletime - graph_start),
-                            (arg_scale_y * 5) - (ptrt * (arg_scale_y * 5)),
-                            time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
-                            ptrt * (arg_scale_y * 5));
+                        fprintf(of, "<rect class=\"cpu\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                time_to_graph(prev_sampledata->sampletime - graph_start),
+                                (arg_scale_y * 5) - (ptrt * (arg_scale_y * 5)),
+                                time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
+                                ptrt * (arg_scale_y * 5));
                 }
                 prev_sampledata = sampledata;
         }
 }
 
-static void svg_wait_bar(int cpu_num) {
+static void svg_wait_bar(FILE *of, struct list_sample_data *head, int n_cpus, int cpu_num, double graph_start) {
 
-        svg("<!-- Wait time aggregation box -->\n");
+        fprintf(of, "<!-- Wait time aggregation box -->\n");
 
         if (cpu_num < 0)
-                svg("<text class=\"t2\" x=\"5\" y=\"-15\">CPU[overall] wait</text>\n");
+                fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">CPU[overall] wait</text>\n");
         else
-                svg("<text class=\"t2\" x=\"5\" y=\"-15\">CPU[%d] wait</text>\n", cpu_num);
+                fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">CPU[%d] wait</text>\n", cpu_num);
 
         /* surrounding box */
-        svg_graph_box(5);
+        svg_graph_box(of, head, 5, graph_start);
 
         /* bars for each sample, proportional to the CPU util. */
         prev_sampledata = head;
@@ -823,7 +820,7 @@ static void svg_wait_bar(int cpu_num) {
                 ptwt = twt = 0.0;
 
                 if (cpu_num < 0)
-                        for (c = 0; c < cpus; c++)
+                        for (c = 0; c < n_cpus; c++)
                                 twt += sampledata->waittime[c] - prev_sampledata->waittime[c];
                 else
                         twt = sampledata->waittime[cpu_num] - prev_sampledata->waittime[cpu_num];
@@ -831,7 +828,7 @@ static void svg_wait_bar(int cpu_num) {
                 twt = twt / 1000000000.0;
 
                 if (cpu_num < 0)
-                        twt = twt / (double)cpus;
+                        twt = twt / (double)n_cpus;
 
                 if (twt > 0.0)
                         ptwt = twt / (sampledata->sampletime - prev_sampledata->sampletime);
@@ -840,38 +837,37 @@ static void svg_wait_bar(int cpu_num) {
                         ptwt = 1.0;
 
                 if (ptwt > 0.001) {
-                        svg("<rect class=\"wait\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                            time_to_graph(prev_sampledata->sampletime - graph_start),
-                            ((arg_scale_y * 5) - (ptwt * (arg_scale_y * 5))),
-                            time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
-                            ptwt * (arg_scale_y * 5));
+                        fprintf(of, "<rect class=\"wait\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                time_to_graph(prev_sampledata->sampletime - graph_start),
+                                ((arg_scale_y * 5) - (ptwt * (arg_scale_y * 5))),
+                                time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
+                                ptwt * (arg_scale_y * 5));
                 }
                 prev_sampledata = sampledata;
         }
 }
 
-static void svg_entropy_bar(void) {
+static void svg_entropy_bar(FILE *of, struct list_sample_data *head, double graph_start) {
 
-        svg("<!-- entropy pool graph -->\n");
+        fprintf(of, "<!-- entropy pool graph -->\n");
 
-        svg("<text class=\"t2\" x=\"5\" y=\"-15\">Entropy pool size</text>\n");
+        fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">Entropy pool size</text>\n");
         /* surrounding box */
-        svg_graph_box(5);
+        svg_graph_box(of, head, 5, graph_start);
 
         /* bars for each sample, scale 0-4096 */
         prev_sampledata = head;
         LIST_FOREACH_BEFORE(link, sampledata, head) {
-                /* svg("<!-- entropy %.03f %i -->\n", sampletime[i], entropy_avail[i]); */
-                svg("<rect class=\"cpu\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                    time_to_graph(prev_sampledata->sampletime - graph_start),
-                    ((arg_scale_y * 5) - ((sampledata->entropy_avail / 4096.) * (arg_scale_y * 5))),
-                    time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
-                    (sampledata->entropy_avail / 4096.) * (arg_scale_y * 5));
+                fprintf(of, "<rect class=\"cpu\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                        time_to_graph(prev_sampledata->sampletime - graph_start),
+                        ((arg_scale_y * 5) - ((sampledata->entropy_avail / 4096.) * (arg_scale_y * 5))),
+                        time_to_graph(sampledata->sampletime - prev_sampledata->sampletime),
+                        (sampledata->entropy_avail / 4096.) * (arg_scale_y * 5));
                 prev_sampledata = sampledata;
         }
 }
 
-static struct ps_struct *get_next_ps(struct ps_struct *ps) {
+static struct ps_struct *get_next_ps(struct ps_struct *ps, struct ps_struct *ps_first) {
         /*
          * walk the list of processes and return the next one to be
          * painted
@@ -919,7 +915,7 @@ static bool ps_filter(struct ps_struct *ps) {
         return 0;
 }
 
-static void svg_do_initcall(int count_only) {
+static void svg_do_initcall(FILE *of, struct list_sample_data *head, int count_only, double graph_start) {
         _cleanup_pclose_ FILE *f = NULL;
         double t;
         char func[256];
@@ -927,17 +923,16 @@ static void svg_do_initcall(int count_only) {
         int usecs;
 
         /* can't plot initcall when disabled or in relative mode */
-        if (!initcall || arg_relative) {
+        if (!arg_initcall || arg_relative) {
                 kcount = 0;
                 return;
         }
 
         if (!count_only) {
-                svg("<!-- initcall -->\n");
-
-                svg("<text class=\"t2\" x=\"5\" y=\"-15\">Kernel init threads</text>\n");
+                fprintf(of, "<!-- initcall -->\n");
+                fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">Kernel init threads</text>\n");
                 /* surrounding box */
-                svg_graph_box(kcount);
+                svg_graph_box(of, head, kcount, graph_start);
         }
 
         kcount = 0;
@@ -983,47 +978,52 @@ static void svg_do_initcall(int count_only) {
                         continue;
                 }
 
-                svg("<!-- thread=\"%s\" time=\"%.3f\" elapsed=\"%d\" result=\"%d\" -->\n",
-                    func, t, usecs, ret);
+                fprintf(of, "<!-- thread=\"%s\" time=\"%.3f\" elapsed=\"%d\" result=\"%d\" -->\n",
+                        func, t, usecs, ret);
 
                 if (usecs < 1000)
                         continue;
 
                 /* rect */
-                svg("  <rect class=\"krnl\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                    time_to_graph(t - (usecs / 1000000.0)),
-                    ps_to_graph(kcount),
-                    time_to_graph(usecs / 1000000.0),
-                    ps_to_graph(1));
+                fprintf(of, "  <rect class=\"krnl\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                        time_to_graph(t - (usecs / 1000000.0)),
+                        ps_to_graph(kcount),
+                        time_to_graph(usecs / 1000000.0),
+                        ps_to_graph(1));
 
                 /* label */
-                svg("  <text x=\"%.03f\" y=\"%.03f\">%s <tspan class=\"run\">%.03fs</tspan></text>\n",
-                    time_to_graph(t - (usecs / 1000000.0)) + 5,
-                    ps_to_graph(kcount) + 15,
-                    func,
-                    usecs / 1000000.0);
+                fprintf(of, "  <text x=\"%.03f\" y=\"%.03f\">%s <tspan class=\"run\">%.03fs</tspan></text>\n",
+                        time_to_graph(t - (usecs / 1000000.0)) + 5,
+                        ps_to_graph(kcount) + 15,
+                        func, usecs / 1000000.0);
 
                 kcount++;
         }
 }
 
-static void svg_ps_bars(void) {
+static void svg_ps_bars(FILE *of,
+                        struct list_sample_data *head,
+                        int n_samples,
+                        int n_cpus,
+                        struct ps_struct *ps_first,
+                        double graph_start,
+                        double interval) {
+
         struct ps_struct *ps;
         int i = 0;
         int j = 0;
         int pid;
         double w = 0.0;
 
-        svg("<!-- Process graph -->\n");
-
-        svg("<text class=\"t2\" x=\"5\" y=\"-15\">Processes</text>\n");
+        fprintf(of, "<!-- Process graph -->\n");
+        fprintf(of, "<text class=\"t2\" x=\"5\" y=\"-15\">Processes</text>\n");
 
         /* surrounding box */
-        svg_graph_box(pcount);
+        svg_graph_box(of, head, pcount, graph_start);
 
         /* pass 2 - ps boxes */
         ps = ps_first;
-        while ((ps = get_next_ps(ps))) {
+        while ((ps = get_next_ps(ps, ps_first))) {
                 _cleanup_free_ char *enc_name = NULL, *escaped = NULL;
                 double endtime;
                 double starttime;
@@ -1037,8 +1037,8 @@ static void svg_ps_bars(void) {
                         continue;
 
                 /* leave some trace of what we actually filtered etc. */
-                svg("<!-- %s [%i] ppid=%i runtime=%.03fs -->\n", enc_name, ps->pid,
-                    ps->ppid, ps->total);
+                fprintf(of, "<!-- %s [%i] ppid=%i runtime=%.03fs -->\n", enc_name, ps->pid,
+                        ps->ppid, ps->total);
 
                 starttime = ps->first->sampledata->sampletime;
 
@@ -1053,20 +1053,20 @@ static void svg_ps_bars(void) {
 
                         /* if this is the last child, we might still need to draw a connecting line */
                         if ((!ps->next) && (ps->parent))
-                                svg("  <line class=\"dot\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                                    ps->parent->pos_x,
-                                    ps_to_graph(j-1) + 10.0, /* whee, use the last value here */
-                                    ps->parent->pos_x,
-                                    ps->parent->pos_y);
+                                fprintf(of, "  <line class=\"dot\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                        ps->parent->pos_x,
+                                        ps_to_graph(j-1) + 10.0, /* whee, use the last value here */
+                                        ps->parent->pos_x,
+                                        ps->parent->pos_y);
                         continue;
                 }
 
                 endtime = ps->last->sampledata->sampletime;
-                svg("  <rect class=\"ps\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                    time_to_graph(starttime - graph_start),
-                    ps_to_graph(j),
-                    time_to_graph(ps->last->sampledata->sampletime - starttime),
-                    ps_to_graph(1));
+                fprintf(of, "  <rect class=\"ps\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                        time_to_graph(starttime - graph_start),
+                        ps_to_graph(j),
+                        time_to_graph(ps->last->sampledata->sampletime - starttime),
+                        ps_to_graph(1));
 
                 /* paint cpu load over these */
                 ps->sample = ps->first;
@@ -1095,18 +1095,18 @@ static void svg_ps_bars(void) {
                         if ((prt < 0.1) && (wrt < 0.1)) /* =~ 26 (color threshold) */
                                 continue;
 
-                        svg("    <rect class=\"wait\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                            time_to_graph(prev->sampledata->sampletime - graph_start),
-                            ps_to_graph(j),
-                            time_to_graph(ps->sample->sampledata->sampletime - prev->sampledata->sampletime),
-                            ps_to_graph(wrt));
+                        fprintf(of, "    <rect class=\"wait\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                time_to_graph(prev->sampledata->sampletime - graph_start),
+                                ps_to_graph(j),
+                                time_to_graph(ps->sample->sampledata->sampletime - prev->sampledata->sampletime),
+                                ps_to_graph(wrt));
 
                         /* draw cpu over wait - TODO figure out how/why run + wait > interval */
-                        svg("    <rect class=\"cpu\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
-                            time_to_graph(prev->sampledata->sampletime - graph_start),
-                            ps_to_graph(j + (1.0 - prt)),
-                            time_to_graph(ps->sample->sampledata->sampletime - prev->sampledata->sampletime),
-                            ps_to_graph(prt));
+                        fprintf(of, "    <rect class=\"cpu\" x=\"%.03f\" y=\"%.03f\" width=\"%.03f\" height=\"%.03f\" />\n",
+                                time_to_graph(prev->sampledata->sampletime - graph_start),
+                                ps_to_graph(j + (1.0 - prt)),
+                                time_to_graph(ps->sample->sampledata->sampletime - prev->sampledata->sampletime),
+                                ps_to_graph(prt));
                         t++;
                 }
 
@@ -1118,34 +1118,34 @@ static void svg_ps_bars(void) {
                         w = starttime;
 
                 /* text label of process name */
-                svg("  <text x=\"%.03f\" y=\"%.03f\"><![CDATA[%s]]> [%i]<tspan class=\"run\">%.03fs</tspan> %s</text>\n",
-                    time_to_graph(w - graph_start) + 5.0,
-                    ps_to_graph(j) + 14.0,
-                    escaped ? escaped : ps->name,
-                    ps->pid,
-                    (ps->last->runtime - ps->first->runtime) / 1000000000.0,
-                    arg_show_cgroup ? ps->cgroup : "");
+                fprintf(of, "  <text x=\"%.03f\" y=\"%.03f\"><![CDATA[%s]]> [%i]<tspan class=\"run\">%.03fs</tspan> %s</text>\n",
+                        time_to_graph(w - graph_start) + 5.0,
+                        ps_to_graph(j) + 14.0,
+                        escaped ? escaped : ps->name,
+                        ps->pid,
+                        (ps->last->runtime - ps->first->runtime) / 1000000000.0,
+                        arg_show_cgroup ? ps->cgroup : "");
                 /* paint lines to the parent process */
                 if (ps->parent) {
                         /* horizontal part */
-                        svg("  <line class=\"dot\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                            time_to_graph(starttime - graph_start),
-                            ps_to_graph(j) + 10.0,
-                            ps->parent->pos_x,
-                            ps_to_graph(j) + 10.0);
+                        fprintf(of, "  <line class=\"dot\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                time_to_graph(starttime - graph_start),
+                                ps_to_graph(j) + 10.0,
+                                ps->parent->pos_x,
+                                ps_to_graph(j) + 10.0);
 
                         /* one vertical line connecting all the horizontal ones up */
                         if (!ps->next)
-                                svg("  <line class=\"dot\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                                    ps->parent->pos_x,
-                                    ps_to_graph(j) + 10.0,
-                                    ps->parent->pos_x,
-                                    ps->parent->pos_y);
+                                fprintf(of, "  <line class=\"dot\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                        ps->parent->pos_x,
+                                        ps_to_graph(j) + 10.0,
+                                        ps->parent->pos_x,
+                                        ps->parent->pos_y);
                 }
 
                 j++; /* count boxes */
 
-                svg("\n");
+                fprintf(of, "\n");
         }
 
         /* last pass - determine when idle */
@@ -1165,7 +1165,7 @@ static void svg_ps_bars(void) {
         ps->sample = ps->first;
         i = ps->sample->next->sampledata->counter;
 
-        while (ps->sample->next && i<(samples-(arg_hz/2))) {
+        while (ps->sample->next && i<(n_samples-(arg_hz/2))) {
                 double crt;
                 double brt;
                 int c;
@@ -1179,7 +1179,7 @@ static void svg_ps_bars(void) {
 
                 /* subtract bootchart cpu utilization from total */
                 crt = 0.0;
-                for (c = 0; c < cpus; c++)
+                for (c = 0; c < n_cpus; c++)
                         crt += sample_hz->sampledata->runtime[c] - ps->sample->sampledata->runtime[c];
                 brt = sample_hz->runtime - ps->sample->runtime;
                 /*
@@ -1190,24 +1190,23 @@ static void svg_ps_bars(void) {
                  */
                 if ((crt - brt) < (interval / 2.0)) {
                         idletime = ps->sample->sampledata->sampletime - graph_start;
-                        svg("\n<!-- idle detected at %.03f seconds -->\n",
-                            idletime);
-                        svg("<line class=\"idle\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
-                            time_to_graph(idletime),
-                            -arg_scale_y,
-                            time_to_graph(idletime),
-                            ps_to_graph(pcount) + arg_scale_y);
-                        svg("<text class=\"idle\" x=\"%.03f\" y=\"%.03f\">%.01fs</text>\n",
-                            time_to_graph(idletime) + 5.0,
-                            ps_to_graph(pcount) + arg_scale_y,
-                            idletime);
+                        fprintf(of, "\n<!-- idle detected at %.03f seconds -->\n", idletime);
+                        fprintf(of, "<line class=\"idle\" x1=\"%.03f\" y1=\"%.03f\" x2=\"%.03f\" y2=\"%.03f\" />\n",
+                                time_to_graph(idletime),
+                                -arg_scale_y,
+                                time_to_graph(idletime),
+                                ps_to_graph(pcount) + arg_scale_y);
+                        fprintf(of, "<text class=\"idle\" x=\"%.03f\" y=\"%.03f\">%.01fs</text>\n",
+                                time_to_graph(idletime) + 5.0,
+                                ps_to_graph(pcount) + arg_scale_y,
+                                idletime);
                         break;
                 }
                 i++;
         }
 }
 
-static void svg_top_ten_cpu(void) {
+static void svg_top_ten_cpu(FILE *of, struct ps_struct *ps_first) {
         struct ps_struct *top[10];
         struct ps_struct emptyps = {};
         struct ps_struct *ps;
@@ -1218,7 +1217,7 @@ static void svg_top_ten_cpu(void) {
 
         /* walk all ps's and setup ptrs */
         ps = ps_first;
-        while ((ps = get_next_ps(ps))) {
+        while ((ps = get_next_ps(ps, ps_first))) {
                 for (n = 0; n < 10; n++) {
                         if (ps->total <= top[n]->total)
                                 continue;
@@ -1230,16 +1229,16 @@ static void svg_top_ten_cpu(void) {
                 }
         }
 
-        svg("<text class=\"t2\" x=\"20\" y=\"0\">Top CPU consumers:</text>\n");
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"0\">Top CPU consumers:</text>\n");
         for (n = 0; n < 10; n++)
-                svg("<text class=\"t3\" x=\"20\" y=\"%d\">%3.03fs - <![CDATA[%s]]> [%d]</text>\n",
-                    20 + (n * 13),
-                    top[n]->total,
-                    top[n]->name,
-                    top[n]->pid);
+                fprintf(of, "<text class=\"t3\" x=\"20\" y=\"%d\">%3.03fs - <![CDATA[%s]]> [%d]</text>\n",
+                        20 + (n * 13),
+                        top[n]->total,
+                        top[n]->name,
+                        top[n]->pid);
 }
 
-static void svg_top_ten_pss(void) {
+static void svg_top_ten_pss(FILE *of, struct ps_struct *ps_first) {
         struct ps_struct *top[10];
         struct ps_struct emptyps = {};
         struct ps_struct *ps;
@@ -1250,7 +1249,7 @@ static void svg_top_ten_pss(void) {
 
         /* walk all ps's and setup ptrs */
         ps = ps_first;
-        while ((ps = get_next_ps(ps))) {
+        while ((ps = get_next_ps(ps, ps_first))) {
                 for (n = 0; n < 10; n++) {
                         if (ps->pss_max <= top[n]->pss_max)
                                 continue;
@@ -1262,30 +1261,39 @@ static void svg_top_ten_pss(void) {
                 }
         }
 
-        svg("<text class=\"t2\" x=\"20\" y=\"0\">Top PSS consumers:</text>\n");
+        fprintf(of, "<text class=\"t2\" x=\"20\" y=\"0\">Top PSS consumers:</text>\n");
         for (n = 0; n < 10; n++)
-                svg("<text class=\"t3\" x=\"20\" y=\"%d\">%dK - <![CDATA[%s]]> [%d]</text>\n",
-                    20 + (n * 13),
-                    top[n]->pss_max,
-                    top[n]->name,
-                    top[n]->pid);
+                fprintf(of, "<text class=\"t3\" x=\"20\" y=\"%d\">%dK - <![CDATA[%s]]> [%d]</text>\n",
+                        20 + (n * 13),
+                        top[n]->pss_max,
+                        top[n]->name,
+                        top[n]->pid);
 }
 
-int svg_do(const char *build) {
+int svg_do(FILE *of,
+           const char *build,
+           struct list_sample_data *head,
+           struct ps_struct *ps_first,
+           int n_samples,
+           int pscount,
+           int n_cpus,
+           double graph_start,
+           double log_start,
+           double interval,
+           int overrun) {
+
         struct ps_struct *ps;
         double offset = 7;
         int r, c;
 
-        memzero(&str, sizeof(str));
-
         ps = ps_first;
 
         /* count initcall thread count first */
-        svg_do_initcall(1);
+        svg_do_initcall(of, head, 1, graph_start);
         ksize = (kcount ? ps_to_graph(kcount) + (arg_scale_y * 2) : 0);
 
         /* then count processes */
-        while ((ps = get_next_ps(ps))) {
+        while ((ps = get_next_ps(ps, ps_first))) {
                 if (!ps_filter(ps))
                         pcount++;
                 else
@@ -1296,70 +1304,70 @@ int svg_do(const char *build) {
         esize = (arg_entropy ? arg_scale_y * 7 : 0);
 
         /* after this, we can draw the header with proper sizing */
-        svg_header();
-        svg("<rect class=\"bg\" width=\"100%%\" height=\"100%%\" />\n\n");
+        svg_header(of, head, graph_start);
+        fprintf(of, "<rect class=\"bg\" width=\"100%%\" height=\"100%%\" />\n\n");
 
-        svg("<g transform=\"translate(10,400)\">\n");
-        svg_io_bi_bar();
-        svg("</g>\n\n");
+        fprintf(of, "<g transform=\"translate(10,400)\">\n");
+        svg_io_bi_bar(of, head, n_samples, graph_start, interval);
+        fprintf(of, "</g>\n\n");
 
-        svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
-        svg_io_bo_bar();
-        svg("</g>\n\n");
+        fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
+        svg_io_bo_bar(of, head, n_samples, graph_start, interval);
+        fprintf(of, "</g>\n\n");
 
-        for (c = -1; c < (arg_percpu ? cpus : 0); c++) {
+        for (c = -1; c < (arg_percpu ? n_cpus : 0); c++) {
                 offset += 7;
-                svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
-                svg_cpu_bar(c);
-                svg("</g>\n\n");
+                fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
+                svg_cpu_bar(of, head, n_cpus, c, graph_start);
+                fprintf(of, "</g>\n\n");
 
                 offset += 7;
-                svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
-                svg_wait_bar(c);
-                svg("</g>\n\n");
+                fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
+                svg_wait_bar(of, head, n_cpus, c, graph_start);
+                fprintf(of, "</g>\n\n");
         }
 
         if (kcount) {
                 offset += 7;
-                svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
-                svg_do_initcall(0);
-                svg("</g>\n\n");
+                fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset));
+                svg_do_initcall(of, head, 0, graph_start);
+                fprintf(of, "</g>\n\n");
         }
 
         offset += 7;
-        svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset) + ksize);
-        svg_ps_bars();
-        svg("</g>\n\n");
+        fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset) + ksize);
+        svg_ps_bars(of, head, n_samples, n_cpus, ps_first, graph_start, interval);
+        fprintf(of, "</g>\n\n");
 
-        svg("<g transform=\"translate(10,  0)\">\n");
-        r = svg_title(build);
-        svg("</g>\n\n");
+        fprintf(of, "<g transform=\"translate(10,  0)\">\n");
+        r = svg_title(of, build, pscount, log_start, overrun);
+        fprintf(of, "</g>\n\n");
 
         if (r < 0)
                 return r;
 
-        svg("<g transform=\"translate(10,200)\">\n");
-        svg_top_ten_cpu();
-        svg("</g>\n\n");
+        fprintf(of, "<g transform=\"translate(10,200)\">\n");
+        svg_top_ten_cpu(of, ps_first);
+        fprintf(of, "</g>\n\n");
 
         if (arg_entropy) {
-                svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset) + ksize + psize);
-                svg_entropy_bar();
-                svg("</g>\n\n");
+                fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset) + ksize + psize);
+                svg_entropy_bar(of, head, graph_start);
+                fprintf(of, "</g>\n\n");
         }
 
         if (arg_pss) {
-                svg("<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset) + ksize + psize + esize);
-                svg_pss_graph();
-                svg("</g>\n\n");
+                fprintf(of, "<g transform=\"translate(10,%.03f)\">\n", 400.0 + (arg_scale_y * offset) + ksize + psize + esize);
+                svg_pss_graph(of, head, ps_first, graph_start);
+                fprintf(of, "</g>\n\n");
 
-                svg("<g transform=\"translate(410,200)\">\n");
-                svg_top_ten_pss();
-                svg("</g>\n\n");
+                fprintf(of, "<g transform=\"translate(410,200)\">\n");
+                svg_top_ten_pss(of, ps_first);
+                fprintf(of, "</g>\n\n");
         }
 
-        /* svg footer */
-        svg("\n</svg>\n");
+        /* fprintf footer */
+        fprintf(of, "\n</svg>\n");
 
         return 0;
 }