timer.c: cleanup

1 files changed, 68 insertions, 101 deletions

diff --git a/timer.c b/timer.c
index 3d43a7c..f2490d1 100644
--- a/timer.c
+++ b/timer.c
@@ -22,62 +22,25 @@
 #include <unistd.h>
 #include <limits.h>
 
-#define SEC_SECOND        1
-#define SEC_MINUTE       60
-#define SEC_HOUR       3600
-#define SEC_DAY       86400
-#define SEC_MONTH   2629746
-#define SEC_YEAR   31556940
-
+static const unsigned long long SEC_SECOND = 1, SEC_MINUTE = 60,
+	     SEC_HOUR = 3600, SEC_DAY = 86400, SEC_MONTH = 2629746,
+	     SEC_YEAR = 31556940;
 static const unsigned long interval_nsec = 1000000000 / 4;
-unsigned short term_width = 0; /* Maybe volatile? */
+
+volatile unsigned short term_width = 0;
 
 void sigwinch(int sig) {
+	struct winsize ws;
+
 	if (sig != SIGWINCH)
 		return;
 
-	struct winsize ws;
-
 	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1)
 		error(1, errno, "Failed to get terminal width");
 
 	term_width = ws.ws_col;
 }
 
-unsigned long int get_seconds(char *code)
-{
-	int length = strlen(code), multiplier = 0;
-	char suffix = code[length - 1], value[length + 1];
-	unsigned long retval;
-
-	if (length < 2) {
-		return 0;
-	}
-
-	switch (suffix) {
-		case 's': multiplier = SEC_SECOND; break; // 1 second
-		case 'm': multiplier = SEC_MINUTE; break; // 1 minute
-		case 'h': multiplier = SEC_HOUR;   break; // 1 hour
-		case 'D': multiplier = SEC_DAY;    break; // 1 day
-		case 'M': multiplier = SEC_MONTH;  break; // 30.4368 days
-		case 'Y': multiplier = SEC_YEAR;   break; // 365.242 days
-		default : return 0;
-	}
-
-	strncpy(value, code, length + 1);
-
-	value[length - 1] = '\0';
-
-	errno = 0;
-
-	retval = strtoul(value, NULL, 10) * multiplier;
-
-	if (retval == ULONG_MAX && errno != 0)
-		error(1, errno, "Error converting time specifier %s", code);
-
-	return retval;
-}
-
 void clear_line(void)
 {
 	if (term_width <= 1)
@@ -85,49 +48,39 @@ void clear_line(void)
 
 	for (unsigned short i = 0; i < term_width - 1; i++)
 		putchar(' ');
-
 	putchar('\r');
 
 	if (fflush(stdout) != 0)
 		error(1, errno, "Failed to flush stdout");
 }
 
+void format_dmy(char *dest, size_t size, const char *name,
+		unsigned long long count)
+{
+	if (count == 1)
+		snprintf(dest, size, "%llu %s, ", count, name);
+	else if (count > 1)
+		snprintf(dest, size, "%llu %ss, ", count, name);
+	else
+		dest[0] = '\0';
+}
 
-void print_time(unsigned long total_sec, bool show_colon)
+void print_time(unsigned long long total_sec, bool show_colon)
 {
-	unsigned long years, months, days, hours, minutes, seconds;
-	char colon = show_colon ? ':' : ' ', syears[128], smonths[16],
-	     sdays[16];
+	unsigned long long count, hours, minutes, seconds;
+	char colon = show_colon ? ':' : ' ', syears[128], smonths[16], sdays[16];
 
-	years = total_sec / SEC_YEAR;
+	count = total_sec / SEC_YEAR;
 	total_sec %= SEC_YEAR;
+	format_dmy(syears, sizeof syears, "year", count);
 
-	if (years == 1)
-		snprintf(syears, sizeof syears, "%lu year, ", years);
-	else if (years > 1)
-		snprintf(syears, sizeof syears, "%lu years, ", years);
-	else
-		syears[0] = '\0';
-
-	months = total_sec / SEC_MONTH;
+	count = total_sec / SEC_MONTH;
 	total_sec %= SEC_MONTH;
+	format_dmy(smonths, sizeof smonths, "month", count);
 
-	if (months == 1)
-		snprintf(smonths, sizeof smonths, "%lu month, ", months);
-	else if (months > 1)
-		snprintf(smonths, sizeof smonths, "%lu months, ", months);
-	else
-		smonths[0] = '\0';
-
-	days = total_sec / SEC_DAY;
+	count = total_sec / SEC_DAY;
 	total_sec %= SEC_DAY;
-
-	if (days == 1)
-		snprintf(sdays, sizeof sdays, "%lu day, ", days);
-	else if (days > 1)
-		snprintf(sdays, sizeof sdays, "%lu days, ", days);
-	else
-		sdays[0] = '\0';
+	format_dmy(sdays, sizeof sdays, "day", count);
 
 	hours = total_sec / SEC_HOUR;
 	total_sec %= SEC_HOUR;
@@ -139,18 +92,45 @@ void print_time(unsigned long total_sec, bool show_colon)
 	total_sec %= SEC_SECOND;
 
 	if (total_sec != 0)
-		error(1, 0, "An error occured during time formatting");
+		error(1, 0, "A bug occured during time formatting");
 
-	printf(" %s%s%s%.2lu%c%.2lu%c%.2lu\r", syears, smonths, sdays, hours,
+	printf(" %s%s%s%.2llu%c%.2llu%c%.2llu\r", syears, smonths, sdays, hours,
 	       colon, minutes, colon, seconds);
 
 	if (fflush(stdout) != 0)
 		error(1, errno, "Failed to flush stdout");
 }
 
-void usage(char *cmd)
+unsigned long long get_seconds(char *code)
 {
-	printf("Usage:\n\t%s <n>{s,m,h,D,M,Y} ...\n", cmd);
+	size_t length = strlen(code);
+	unsigned long long multiplier, retval;
+	char suffix, value[length];
+
+	if (length < 2)
+		return 0;
+
+	suffix = code[length - 1];
+	switch (suffix) {
+		case 's': multiplier = SEC_SECOND; break; /* 1 second */
+		case 'm': multiplier = SEC_MINUTE; break; /* 1 minute */
+		case 'h': multiplier = SEC_HOUR; break;	  /* 1 hour */
+		case 'D': multiplier = SEC_DAY; break;	  /* 1 day */
+		case 'M': multiplier = SEC_MONTH; break;  /* 30.4368 days */
+		case 'Y': multiplier = SEC_YEAR; break;	  /* 365.242 days */
+		default: return 0;
+	}
+
+	strncpy(value, code, sizeof value);
+
+	value[sizeof value - 1] = '\0';
+
+	errno = 0;
+	retval = strtoul(value, NULL, 10) * multiplier; /* Possibly might overflow */
+	if (retval == ULONG_MAX && errno != 0)
+		error(1, errno, "Error converting time specifier %s", code);
+
+	return retval;
 }
 
 int main(int argc, char **argv)
@@ -158,42 +138,29 @@ int main(int argc, char **argv)
 	bool blink = false;
 	int sig;
 	sigset_t sigset;
-	struct itimerspec its;
-	struct sigevent sev;
-	struct sigaction sigact;
+	struct itimerspec its = {{0, interval_nsec}, {0, interval_nsec}};
+	struct sigaction sigact = {.sa_handler = sigwinch};
 	timer_t timerid;
-
-	unsigned long total_seconds = 0;
+	struct sigevent sev = {.sigev_notify = SIGEV_SIGNAL,
+		.sigev_signo = SIGRTMIN, .sigev_value.sival_ptr = &timerid};
+	unsigned long long total_seconds = 0;
 
 	if (!isatty(STDOUT_FILENO))
 		error(1, 0, "Error: stdout is not a tty");
 
-	if (argc < 2) {
-		fprintf(stderr, "Not enough arguments.\n");
-		usage(argv[0]);
-		exit(1);
-	}
+	if (argc < 2)
+		error(1, 0, "Not enough arguments.\nUsage:\n"
+		      "\t%s <n>{s,m,h,D,M,Y} ...", argv[0]);
 
 	for (int i = 1; i < argc; i++)
 		total_seconds += get_seconds(argv[i]);
 
-	sigact.sa_handler = sigwinch;
-
 	if (sigaction(SIGWINCH, &sigact, NULL) != 0)
 		error(1, errno, "Unable to set SIGWINCH signal action");
 
-	sev.sigev_notify = SIGEV_SIGNAL;
-	sev.sigev_signo = SIGRTMIN;
-	sev.sigev_value.sival_ptr = &timerid;
-
 	if (timer_create(CLOCK_MONOTONIC, &sev, &timerid) != 0)
 		error(1, errno, "Could not create timer");
 
-	its = (struct itimerspec){
-		{0, interval_nsec},
-		{0, interval_nsec}
-	};
-
 	if (sigemptyset(&sigset) != 0)
 		error(1, errno, "Could not empty signal set");
 
@@ -208,12 +175,12 @@ int main(int argc, char **argv)
 
 	sigwinch(SIGWINCH);
 
-	for (unsigned long i = 0; i < total_seconds; i++)
+	for (unsigned long long i = 0; i < total_seconds; i++)
 		for (int ii = 0; ii < 4; ii++) {
 			if (sigwait(&sigset, &sig), sig != SIGRTMIN)
 				error(1, 0, "sigwait returned unexpected signal %d", sig);
 			if (sigaddset(&sigset, SIGRTMIN) != 0)
-				error(1, errno, "Could not add signal to set");
+				error(1, errno, "Could not add SIGRTMIN to signal set");
 
 			clear_line();
 			print_time(total_seconds - i, ii < 2);
@@ -229,7 +196,7 @@ int main(int argc, char **argv)
 			break;
 
 		if (sigaddset(&sigset, SIGRTMIN) != 0)
-			error(1, errno, "Could not add signal to set");
+			error(1, errno, "Could not add SIGRTMIN to signal set");
 
 		clear_line();