From 262fd581a79f61ee99b018938c480cf318ba6bd6 Mon Sep 17 00:00:00 2001
From: clsr <clsr@clsr.net>
Date: Wed, 26 Apr 2017 10:41:48 +0200
Subject: Deduplicate file reading code and add battery charging indicator

---
 Makefile      |  2 +-
 README.md     |  6 +++---
 config.def.mk |  3 +++
 dwmclock.c    | 57 ++++++++++++++++++++++++++++++++++++++++-----------------
 4 files changed, 47 insertions(+), 21 deletions(-)

diff --git a/Makefile b/Makefile
index 9aa9a59..753018d 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@ $(MAIN): $(OBJ)
 	$(CC) $(LDFLAGS) -o $@ $(OBJ)
 
 .c.o:
-	$(CC) -c $(CFLAGS) $< -o $@
+	$(CC) -c $(CFLAGS) $< -o $@ -O2
 
 clean:
 	-rm -f $(MAIN) $(OBJ)
diff --git a/README.md b/README.md
index 7761fd4..06f333b 100644
--- a/README.md
+++ b/README.md
@@ -20,9 +20,9 @@ Compile it:
 
 Install dwmclock (needs to be run as root if installing to `/usr` or `/usr/local`):
 
-	make instal
+	make install
 
-Install dwmclock to ~/bin:
+Install dwmclock to `~/bin`:
 
 	make DESTDIR=$HOME PREFIX= install
 
@@ -30,6 +30,6 @@ Install dwmclock to ~/bin:
 Usage
 -----
 
-Amp it off in your ~/.xinitrc:
+Amp it off in your `~/.xinitrc`:
 
 	dwmclock &
diff --git a/config.def.mk b/config.def.mk
index a01d057..1860aaf 100644
--- a/config.def.mk
+++ b/config.def.mk
@@ -6,6 +6,9 @@ CFLAGS+=-DBATTERY
 # set this to the correct path for your current system
 CFLAGS+=-DENERGY_FULL=\"/sys/class/power_supply/BAT0/energy_full\"
 CFLAGS+=-DENERGY_NOW=\"/sys/class/power_supply/BAT0/energy_now\"
+CFLAGS+=-DSTATUS=\"/sys/class/power_supply/BAT0/status\"
+# the string to match when the battery is charging; comment out to disable charging detection
+CFLAGS+=-DCHARGING=\"Charging\\n\"
 
 # possible alternative on some systems
 #CFLAGS+=-DENERGY_FULL=\"/sys/class/power_supply/BAT0/charge_full\"
diff --git a/dwmclock.c b/dwmclock.c
index cc4b5b2..e7fd938 100644
--- a/dwmclock.c
+++ b/dwmclock.c
@@ -4,6 +4,7 @@
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <time.h>
 #include <unistd.h>
 #include <X11/Xlib.h>
@@ -12,29 +13,47 @@
 int stop = 0;
 
 #ifdef BATTERY
-int getnum(char *fn)
-{
-	char buf[1024];
+char *readfile(char *buf, size_t len, const char *fn) {
 	FILE *f;
-	int len;
+	size_t n;
 
 	f = fopen(fn, "r");
 	if (!f) {
-		return -1;
+		return NULL;
 	}
-	len = fread(buf, 1, 1023, f);
+	n = fread(buf, 1, len-1, f);
 	if (ferror(f)) {
-		return -1;
+		return NULL;
 	}
 	fclose(f);
-	if (len > 1022 || len < 1) {
-		return -1;
+	if (n >= len-1 || n < 1) {
+		return NULL;
 	}
-	buf[1023] = '\0';
+	buf[n] = '\0';
+
+	return buf;
+}
 
-	return atoi(buf);
+int getnum(const char *fn) {
+	char buf[1024];
+
+	if (readfile(buf, sizeof(buf), fn)) {
+		return atoi(buf);
+	}
+	return -1;
+}
+
+#ifdef CHARGING
+int charging(void) {
+	char buf[1024];
+
+	if (readfile(buf, sizeof(buf), STATUS)) {
+		return !strcmp(buf, CHARGING);
+	}
+	return 0;
 }
-#endif
+#endif /* CHARGING */
+#endif /* BATTERY */
 
 void handler(int sig)
 {
@@ -50,10 +69,11 @@ int main(void)
 	char name[8 + 9]; /* (p)pp.pp% hh:mm:ss\0 */
 	char *perc = name;
 	char *clock = name + 8;
+	char sign = '%';
 #else
 	char name[9]; /* hh:mm:ss\0 */
 	char *clock = name;
-#endif
+#endif /* BATTERY */
 	struct sigaction act;
 	Display *disp;
 	int screen;
@@ -73,7 +93,7 @@ int main(void)
 	for (i=0; !stop; ++i) {
 #else
 	while (!stop) {
-#endif
+#endif /* BATTERY */
 		if (!disp) {
 			puts("Cannot open display!");
 			return 1;
@@ -84,6 +104,9 @@ int main(void)
 		if (i % (BAT_REFRESH_SECONDS) == 0) {
 			curr = getnum(ENERGY_NOW) * MUL;
 			max = getnum(ENERGY_FULL);
+#ifdef CHARGING
+			sign = charging() ? '+' : '%';
+#endif /* CHARGING */
 			if (curr < 0 || max < 1) {
 				a = b = -1;
 			} else {
@@ -98,12 +121,12 @@ int main(void)
 		} else if (a < 0 || a > 999999 || b < 0 || b > 99) {
 			snprintf(perc, 8, "INVALID");
 		} else if (a > 999) {
-			snprintf(perc, 8, "%6lld%%", a);
+			snprintf(perc, 8, "%6lld%c", a, sign);
 		} else {
-			snprintf(perc, 8, "%3lld.%02lld%%", a, b);
+			snprintf(perc, 8, "%3lld.%02lld%c", a, b, sign);
 		}
 		perc[7] = ' ';
-#endif
+#endif /* BATTERY */
 
 		now = time(NULL);
 		tm = localtime(&now);
-- 
cgit