Implement Exponential Moving Average algorithm

For solving that CPU status updating is so fast, use EMA to calc a
smooth value

2 files changed, 229 insertions, 181 deletions

diff --git a/stat.c b/stat.c
index c0d94a3..17f9af3 100644
--- a/stat.c
+++ b/stat.c
@@ -12,190 +12,238 @@
 #include "log.h"
 #include "mem.h"
 
-stat* stat_init() {
-    stat* s = xmalloc(sizeof(stat));
-    *s = (stat){
-        .sysver = "",
-        .meminfo = {.mem_available = 0, .mem_total = 0},
-        .diskinfo = {.disk_available = 0, .disk_total = 0},
-    };
-
-    return s;
+stat *stat_init()
+{
+	stat *s = xmalloc(sizeof(stat));
+	*s = (stat){
+	    .sysver = "",
+	    .meminfo = {.mem_available = 0, .mem_total = 0},
+	    .diskinfo = {.disk_available = 0, .disk_total = 0},
+	};
+	s->cpu_occ = xmalloc(sizeof(cpu_occupy));
+
+	if (s->cpu_occ)
+		*s->cpu_occ = (cpu_occupy){0};
+	return s;
 }
 
-void stat_get_sysver(stat* s) {
-    FILE* fp = fopen(PROC_PATH_VERSION, "r");
-    if (!fp) die("Cannot open %s", PROC_PATH_VERSION);
+void stat_get_sysver(stat *s)
+{
+	FILE *fp = fopen(PROC_PATH_VERSION, "r");
+	if (!fp)
+		die("Cannot open %s", PROC_PATH_VERSION);
 
-    if (fgets(s->sysver, sizeof(s->sysver), fp) != NULL) {
-        s->sysver[strcspn(s->sysver, "\n")] = '\0';
-    }
-    fclose(fp);
+	if (fgets(s->sysver, sizeof(s->sysver), fp) != NULL) {
+		s->sysver[strcspn(s->sysver, "\n")] = '\0';
+	}
+	fclose(fp);
 }
-void stat_print_cpu_info(WINDOW* w, int y, int maxx, stat* s) {
-    mvwprintw(w, y, maxx - STAT_INFO_WIDTH, " %.2f %%", s->cpu_occupy.cpu);
+void stat_print_cpu_info(WINDOW *w, int y, int maxx, stat *s)
+{
+	mvwprintw(w, y, maxx - STAT_INFO_WIDTH, " %.2f %%",
+		  s->cpu_occ->smooth_cpu);
 }
-void stat_print_info(WINDOW* w, int y, int maxx, const char* label,
-                     unsigned long total, unsigned long ava) {
-    unsigned long long t_bytes = total;
-    unsigned long long a_bytes = ava;
+void stat_print_info(WINDOW *w, int y, int maxx, const char *label,
+		     unsigned long total, unsigned long ava)
+{
+	unsigned long long t_bytes = total;
+	unsigned long long a_bytes = ava;
 
-    if (strcmp(label, "Mem") == 0 || strcmp(label, "Mem ") == 0) {
-        t_bytes *= 1024;
-        a_bytes *= 1024;
-    }
+	if (strcmp(label, "Mem") == 0 || strcmp(label, "Mem ") == 0) {
+		t_bytes *= 1024;
+		a_bytes *= 1024;
+	}
 
-    const char* units[] = {"B", "K", "M", "G", "T"};
+	const char *units[] = {"B", "K", "M", "G", "T"};
 
-    int t_idx = 0;
-    int a_idx = 0;
+	int t_idx = 0;
+	int a_idx = 0;
 
-    double d_total = (double)t_bytes;
-    double d_ava = (double)a_bytes;
+	double d_total = (double)t_bytes;
+	double d_ava = (double)a_bytes;
 
-    while (d_total >= 1024.0 && t_idx < 4) {
-        d_total /= 1024.0;
-        t_idx++;
-    }
+	while (d_total >= 1024.0 && t_idx < 4) {
+		d_total /= 1024.0;
+		t_idx++;
+	}
 
-    while (d_ava >= 1024.0 && a_idx < 4) {
-        d_ava /= 1024.0;
-        a_idx++;
-    }
+	while (d_ava >= 1024.0 && a_idx < 4) {
+		d_ava /= 1024.0;
+		a_idx++;
+	}
 
-    int startx = maxx - STAT_INFO_WIDTH;
+	int startx = maxx - STAT_INFO_WIDTH;
 
-    mvwprintw(w, y, startx, " %.2f%s/%.2f%s", d_ava, units[t_idx], d_total,
-              units[t_idx]);
+	mvwprintw(w, y, startx, " %.2f%s/%.2f%s", d_ava, units[t_idx], d_total,
+		  units[t_idx]);
 
-    /* wrefresh(w); */
+	/* wrefresh(w); */
 }
 
 int stat_get_bar_ticks(int maxx, unsigned long long total,
-                       unsigned long long ava) {
-    if (total == 0) return 0;
-    if (ava >= total) return 0;
+		       unsigned long long ava)
+{
+	if (total == 0)
+		return 0;
+	if (ava >= total)
+		return 0;
 
-    unsigned long long used = total - ava;
+	unsigned long long used = total - ava;
 
-    unsigned long long slots = (unsigned long long)(maxx);
+	unsigned long long slots = (unsigned long long)(maxx);
 
-    return (int)((slots * used) / total);
+	return (int)((slots * used) / total);
 }
 
-void stat_draw_cpu_bar(WINDOW* w, int maxx, int y, int x, stat* s) {
-    int ava_to_draw_x = maxx - STAT_INFO_WIDTH - BAR_LABEL_WIDTH;
-    int total_hashes = ava_to_draw_x * s->cpu_occupy.cpu;
-    log_write(LOG_INFO, "stat_draw_cpu_bar: ava_to_draw = %d", ava_to_draw_x);
-    log_write(LOG_INFO, "s->cpu_occupy.cpu = %f", s->cpu_occupy.cpu);
-    log_write(LOG_INFO, "CPU Hashes = %d", total_hashes);
-    char hashes[2048] = {0};
+void stat_draw_cpu_bar(WINDOW *w, int maxx, int y, int x, stat *s)
+{
+	int ava_to_draw_x = maxx - STAT_INFO_WIDTH - BAR_LABEL_WIDTH;
+	int total_hashes = ava_to_draw_x * (s->cpu_occ->smooth_cpu * 0.1);
 
-    if (total_hashes > ava_to_draw_x) total_hashes = ava_to_draw_x;
-    memset(hashes, '#', total_hashes);
-    hashes[total_hashes] = '\0';
+	char hashes[2048] = {0};
 
-    mvwprintw(w, y, x, "%-*s [", 4, "CPU");
-    wprintw_colorful(w, COLOR_PAIR_PROGRESS, "%.*s", total_hashes, hashes);
+	if (total_hashes > ava_to_draw_x)
+		total_hashes = ava_to_draw_x;
+	memset(hashes, '#', total_hashes);
+	hashes[total_hashes] = '\0';
 
-    int remaining_spaces = ava_to_draw_x - total_hashes;
-    if (remaining_spaces > 0) {
-        wprintw(w, "%*s", remaining_spaces, "");
-    }
+	mvwprintw(w, y, x, "%-*s [", 4, "CPU");
+	wprintw_colorful(w, COLOR_PAIR_PROGRESS, "%.*s", total_hashes, hashes);
 
-    waddch(w, ']');
-}
+	int remaining_spaces = ava_to_draw_x - total_hashes;
+	if (remaining_spaces > 0) {
+		wprintw(w, "%*s", remaining_spaces, "");
+	}
 
-void stat_draw_bar(WINDOW* w, const char* label, int maxx, int y, int x,
-                   unsigned long total, unsigned long ava) {
-    int ava_to_draw_x = maxx - STAT_INFO_WIDTH - BAR_LABEL_WIDTH;
-    int total_hashes = stat_get_bar_ticks(ava_to_draw_x, total, ava);
-    char hashes[2048] = {0};
+	waddch(w, ']');
+}
 
-    init_pair(COLOR_PAIR_PROGRESS, COLOR_GREEN, COLOR_BLACK);
+void stat_draw_bar(WINDOW *w, const char *label, int maxx, int y, int x,
+		   unsigned long total, unsigned long ava)
+{
+	int ava_to_draw_x = maxx - STAT_INFO_WIDTH - BAR_LABEL_WIDTH;
+	int total_hashes = stat_get_bar_ticks(ava_to_draw_x, total, ava);
+	char hashes[2048] = {0};
 
-    if (total_hashes > ava_to_draw_x) total_hashes = ava_to_draw_x;
-    memset(hashes, '#', total_hashes);
-    hashes[total_hashes] = '\0';
+	init_pair(COLOR_PAIR_PROGRESS, COLOR_GREEN, COLOR_BLACK);
 
-    mvwprintw(w, y, x, "%-*s [", 4, label);
-    wprintw_colorful(w, COLOR_PAIR_PROGRESS, "%.*s", total_hashes, hashes);
+	if (total_hashes > ava_to_draw_x)
+		total_hashes = ava_to_draw_x;
+	memset(hashes, '#', total_hashes);
+	hashes[total_hashes] = '\0';
 
-    int remaining_spaces = ava_to_draw_x - total_hashes;
-    if (remaining_spaces > 0) {
-        wprintw(w, "%*s", remaining_spaces, "");
-    }
+	mvwprintw(w, y, x, "%-*s [", 4, label);
+	wprintw_colorful(w, COLOR_PAIR_PROGRESS, "%.*s", total_hashes, hashes);
 
-    waddch(w, ']');
+	int remaining_spaces = ava_to_draw_x - total_hashes;
+	if (remaining_spaces > 0) {
+		wprintw(w, "%*s", remaining_spaces, "");
+	}
 
-    /* wrefresh(w); */
-}
+	waddch(w, ']');
 
-void stat_get_meminfo(stat* s) {
-    static char buf[128];
-    char key[32] = "";
-    unsigned long long val = 0;
-
-    FILE* fp = fopen(PROC_PATH_MEMINFO, "r");
-    if (!fp) die("Cannot open %s", PROC_PATH_MEMINFO);
-
-    while (fgets(buf, sizeof(buf), fp)) {
-        if (sscanf(buf, "%31[^:]: %llu", key, &val) == 2) {
-            if (strcmp(key, "MemTotal") == 0) {
-                s->meminfo.mem_total = val;
-            } else if (strcmp(key, "MemAvailable") == 0) {
-                s->meminfo.mem_available = val;
-                break;
-            }
-        }
-    }
-
-    fclose(fp);
+	/* wrefresh(w); */
 }
 
-void stat_get_diskinfo(stat* s) {
-    struct statvfs vfs;
-    if (statvfs("/", &vfs) != 0) {
-        s->diskinfo.disk_total = 0;
-        s->diskinfo.disk_available = 0;
-        log_write(LOG_WARN, "Cannot get disk info");
-    }
-
-    s->diskinfo.disk_total = (unsigned long long)vfs.f_blocks * vfs.f_frsize;
-    s->diskinfo.disk_available =
-        (unsigned long long)vfs.f_bavail * vfs.f_frsize;
+void stat_get_meminfo(stat *s)
+{
+	static char buf[128];
+	char key[32] = "";
+	unsigned long long val = 0;
+
+	FILE *fp = fopen(PROC_PATH_MEMINFO, "r");
+	if (!fp)
+		die("Cannot open %s", PROC_PATH_MEMINFO);
+
+	while (fgets(buf, sizeof(buf), fp)) {
+		if (sscanf(buf, "%31[^:]: %llu", key, &val) == 2) {
+			if (strcmp(key, "MemTotal") == 0) {
+				s->meminfo.mem_total = val;
+			} else if (strcmp(key, "MemAvailable") == 0) {
+				s->meminfo.mem_available = val;
+				break;
+			}
+		}
+	}
+
+	fclose(fp);
 }
 
-void stat_get_cpuinfo(stat* s) {
-    char buf[128];
-    FILE* fp = fopen(PROC_PATH_STAT, "r");
-    if (!fp) {
-        log_write(LOG_WARN, "Cannot open %s", PROC_PATH_STAT);
-        return;
-    }
-
-    fgets(buf, sizeof(buf), fp);
-    sscanf(buf, "%s %llu %llu %llu %llu", s->cpu_occupy.name,
-           &s->cpu_occupy.user, &s->cpu_occupy.nice, &s->cpu_occupy.system,
-           &s->cpu_occupy.idle);
-    fclose(fp);
+void stat_get_diskinfo(stat *s)
+{
+	struct statvfs vfs;
+	if (statvfs("/", &vfs) != 0) {
+		s->diskinfo.disk_total = 0;
+		s->diskinfo.disk_available = 0;
+		log_write(LOG_WARN, "Cannot get disk info");
+	}
+
+	s->diskinfo.disk_total =
+	    (unsigned long long)vfs.f_blocks * vfs.f_frsize;
+	s->diskinfo.disk_available =
+	    (unsigned long long)vfs.f_bavail * vfs.f_frsize;
 }
 
-void stat_calc_cpuocc(stat* s) {
-    cpu_occupy* co = xmalloc(sizeof(cpu_occupy));
-    stat_get_cpuinfo(s);
-    co->idle = s->cpu_occupy.idle;
-    co->nice = s->cpu_occupy.nice;
-    co->system = s->cpu_occupy.system;
-    co->user = s->cpu_occupy.user;
-    usleep(200000);
-    stat_get_cpuinfo(s);
-    unsigned long long t1 = co->user + co->nice + co->system + co->idle;
-    unsigned long long t2 = s->cpu_occupy.user + s->cpu_occupy.nice +
-                            s->cpu_occupy.system + s->cpu_occupy.idle;
-    unsigned long long user = s->cpu_occupy.user - co->user;
-    unsigned long long system = s->cpu_occupy.system - co->system;
-
-    s->cpu_occupy.cpu = (user + system) * 1.0 / (t2 - t1);
-    free(co);
+void stat_get_cpuinfo(stat *s)
+{
+	char buf[256];
+	FILE *fp = fopen(PROC_PATH_STAT, "r");
+	if (!fp) {
+		log_write(LOG_WARN, "Cannot open %s", PROC_PATH_STAT);
+		return;
+	}
+
+	if (!fgets(buf, sizeof(buf), fp)) {
+		fclose(fp);
+		return;
+	}
+	fclose(fp);
+
+	unsigned long long user = 0, nice = 0, system = 0, idle = 0;
+	unsigned long long iowait = 0, irq = 0, softirq = 0;
+
+	sscanf(buf, "%*s %llu %llu %llu %llu %llu %llu %llu", &user, &nice,
+	       &system, &idle, &iowait, &irq, &softirq);
+
+	s->cpu_occ->user = user;
+	s->cpu_occ->nice = nice;
+	s->cpu_occ->system = system;
+	s->cpu_occ->idle = idle;
+	s->cpu_occ->iowait = iowait;
+	s->cpu_occ->irq = irq;
+	s->cpu_occ->softirq = softirq;
+
+	unsigned long long curr_idle = idle + iowait;
+	unsigned long long curr_total =
+	    user + nice + system + idle + iowait + irq + softirq;
+
+	unsigned long long total_diff = curr_total - s->cpu_occ->prev_total;
+	unsigned long long idle_diff = curr_idle - s->cpu_occ->prev_idle;
+
+	if (total_diff > 0) {
+		s->cpu_occ->cpu = (double)(total_diff - idle_diff) /
+				  (double)total_diff * 100.0;
+	} else {
+		s->cpu_occ->cpu = 0.0; // 防零除
+	}
+
+	s->cpu_occ->prev_total = curr_total;
+	s->cpu_occ->prev_idle = curr_idle;
+
+	/* EMA - Exponential Moving Average */
+	/* DisplayCPU = alpha * raw_cpu + (1 - alpha) * pre_cpu */
+	double alpha = 0.1;
+	if (total_diff > 0) {
+		double raw_cpu = (double)(total_diff - idle_diff) /
+				 (double)total_diff * 100.0;
+		if (s->cpu_occ->smooth_cpu == 0.0) {
+			s->cpu_occ->smooth_cpu = raw_cpu;
+		} else {
+			s->cpu_occ->smooth_cpu =
+			    alpha * raw_cpu +
+			    (1 - alpha) * s->cpu_occ->smooth_cpu;
+		}
+
+		s->cpu_occ->cpu = raw_cpu;
+	}
 }
diff --git a/stat.h b/stat.h
index 81d84cc..5b14226 100644
--- a/stat.h
+++ b/stat.h
@@ -12,46 +12,46 @@
 #define STAT_BAR_HEIGHT 1
 
 typedef struct {
-    char name[16];
-    unsigned int user;   /* User mode */
-    unsigned int nice;   /* Low-priority user mode */
-    unsigned int system; /* Kernel mode */
-    unsigned int idle;   /* Free time of CPU */
+	char name[16];
+	unsigned int user;   /* User mode */
+	unsigned int nice;   /* Low-priority user mode */
+	unsigned int system; /* Kernel mode */
+	unsigned int idle;   /* Free time of CPU */
+	unsigned long long iowait;
+	unsigned long long irq;
+	unsigned long long softirq;
+
+	unsigned long long prev_total;
+	unsigned long long prev_idle;
+	double cpu;
+	double smooth_cpu;
 } cpu_occupy;
 
 typedef struct {
-    char sysver[30];
-    struct {
-        unsigned long mem_total;
-        unsigned long mem_available;
-    } meminfo;
-    struct {
-        unsigned long long disk_total;
-        unsigned long long disk_available;
-    } diskinfo;
-    struct {
-        char name[16];
-        unsigned long long user;   /* User mode */
-        unsigned long long nice;   /* Low-priority user mode */
-        unsigned long long system; /* Kernel mode */
-        unsigned long long idle;   /* Free time of CPU */
-        double cpu;
-    } cpu_occupy;
+	char sysver[30];
+	struct {
+		unsigned long mem_total;
+		unsigned long mem_available;
+	} meminfo;
+	struct {
+		unsigned long long disk_total;
+		unsigned long long disk_available;
+	} diskinfo;
+	cpu_occupy *cpu_occ;
 } stat;
 
-void stat_get_sysver(stat* s);
-stat* stat_init();
-void stat_print_info(WINDOW* w, int y, int maxx, const char* label,
-                     unsigned long total, unsigned long ava);
-void stat_print_cpu_info(WINDOW* w, int y, int maxx, stat* s);
-void stat_draw_bar(WINDOW* w, const char* label, int maxx, int y, int x,
-                   unsigned long total, unsigned long ava);
-void stat_draw_cpu_bar(WINDOW* w, int maxx, int y, int x, stat* s);
-void stat_get_meminfo(stat* s);
-void stat_get_diskinfo(stat* s);
-void stat_get_cpuinfo(stat* s);
-void stat_calc_cpuocc(stat* s);
+void stat_get_sysver(stat *s);
+stat *stat_init();
+void stat_print_info(WINDOW *w, int y, int maxx, const char *label,
+		     unsigned long total, unsigned long ava);
+void stat_print_cpu_info(WINDOW *w, int y, int maxx, stat *s);
+void stat_draw_bar(WINDOW *w, const char *label, int maxx, int y, int x,
+		   unsigned long total, unsigned long ava);
+void stat_draw_cpu_bar(WINDOW *w, int maxx, int y, int x, stat *s);
+void stat_get_meminfo(stat *s);
+void stat_get_diskinfo(stat *s);
+void stat_get_cpuinfo(stat *s);
 int stat_get_bar_ticks(int maxx, unsigned long long total,
-                       unsigned long long ava);
+		       unsigned long long ava);
 
 #endif /* SF_STAT_H */