More minor bugfixes

- make pollcat_loop() work as expected with no structs linked, by
  - calling usleep() instead of poll()
  - refactoring delay calculation and reset into pollcat_time_value()
- simplify pollcat_timer_dispatch() in case of slow callbacks
  - deprecate pollcat_timer_dispatch_thresh
- revise tests/timer.c to support two new options:
  - -s to monitor stdin with pollcat_fd_add()
  - -w to use pollcat_loop() instead of handling main-loop separately
- make pollcat_dump() always present in header, since it's always compiled in
- add Makefile rules for installing tests, for easier running on cross-compiled targets

include/pollcat/pollcat.h

@@ -1,7 +1,7 @@
 /** Wrapper structure for poll()
  *
  *  This file is part of the Pollcat Library.
- *  Copyright (C) 2022 Expatria Technologies Inc.
+ *  Copyright (C) 2022,2025 Expatria Technologies Inc.
  *  Contact: Morgan Hughes <morgan@expatria.ca>
  *
  *  The Pollcat Library is free software: you can redistribute it and/or modify it under
@@ -40,9 +40,7 @@
 
 #include <stdlib.h>
 #include <poll.h>
-#if POLLCAT_DEBUG
 #include <stdio.h>
-#endif
 
 
 /** Optional function to call on fatal error; if unset an assert()-style message will be
@@ -123,11 +121,9 @@ void pollcat_time_reduce (int time);
 int pollcat_poll (void);
 
 
-#if POLLCAT_DEBUG
+/** Prints the pollfd array to a given file handle, if POLLCAT_DEBUG is nonzero
-/** Prints the pollfd array to a given file handle
  */
 void pollcat_dump (FILE *fp);
-#endif
 
 
 #endif /* _INCLUDE_POLLCAT_POLLCAT_H_ */

include/pollcat/timer.h

@@ -28,8 +28,9 @@
 typedef uint64_t pollcat_time_t;
 
 
-/** Grace period in milliseconds for late timers, set to 0 for exact match */
+/** This was removed and replaced with a simpler implementation which allowed slow/late
-extern pollcat_time_t  pollcat_timer_dispatch_thresh;
+ *  timers to run reliably.  Setting it now has no effect. */
+extern pollcat_time_t  pollcat_timer_dispatch_thresh __attribute__((deprecated));
 
 
 /** Maximum number of times to run the dispatch loop, set to -1 for no limit */

src/pollcat.c

@@ -1,7 +1,7 @@
 /** Wrapper structure for poll()
  *
  *  This file is part of the Pollcat Library.
- *  Copyright (C) 2022 Expatria Technologies Inc.
+ *  Copyright (C) 2022,2025 Expatria Technologies Inc.
  *  Contact: Morgan Hughes <morgan@expatria.ca>
  *
  *  The Pollcat Library is free software: you can redistribute it and/or modify it under
@@ -284,6 +284,23 @@ void pollcat_time_reduce (int time)
 		pollcat_time_current = time;
 }
 
+/** Return the current timeout and reset the current timeout to the base value
+ *
+ *  \return  Timeout in milliseconds
+ */
+int pollcat_time_value (void)
+{
+	/* latch current value, which may have been reduced by pollcat_time_reduce() */
+	int value = pollcat_time_current;
+
+	/* enforce minimum */
+	if ( value < pollcat_time_minimum )
+		value = pollcat_time_minimum;
+
+	/* reset to base before return, for next call */
+	pollcat_time_current = pollcat_time_base;
+	return value;
+}
 
 /** Wraps the system poll() command using the internal pollfd array and timeout
  *
@@ -296,11 +313,7 @@ int pollcat_poll (void)
 	/* Auto init, no-return if failed */
 	pollcat_init();
 
-	if ( pollcat_time_current < pollcat_time_minimum )
+	ret = poll(pollcat_list, pollcat_used, pollcat_time_value());
-		pollcat_time_current = pollcat_time_minimum;
-
-	ret = poll(pollcat_list, pollcat_used, pollcat_time_current);
-	pollcat_time_current = pollcat_time_base;
 
 	return ret;
 }

src/private.h

@@ -1,7 +1,7 @@
 /** Private includes
  *
  *  This file is part of the Pollcat Library.
- *  Copyright (C) 2022 Expatria Technologies Inc.
+ *  Copyright (C) 2022,2025 Expatria Technologies Inc.
  *  Contact: Morgan Hughes <morgan@expatria.ca>
  *
  *  The Pollcat Library is free software: you can redistribute it and/or modify it under
@@ -40,4 +40,8 @@
 extern pollcat_assert_f pollcat_assert_func;
 
 
+/** Return the current timeout and reset the current timeout to the base value */
+int pollcat_time_value (void);
+
+
 #endif /* _SRC_PRIVATE_H_ */

src/struct.c

@@ -1,7 +1,7 @@
 /** Registration struct, iterators, and main-loop convenience functions
  *
  *  This file is part of the Pollcat Library.
- *  Copyright (C) 2022 Expatria Technologies Inc.
+ *  Copyright (C) 2022,2025 Expatria Technologies Inc.
  *  Contact: Morgan Hughes <morgan@expatria.ca>
  *
  *  The Pollcat Library is free software: you can redistribute it and/or modify it under
@@ -21,6 +21,7 @@
  */
 #include <stdint.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 #include <pollcat.h>
 #include "private.h"
@@ -145,8 +146,18 @@ int pollcat_loop (int *poll_ret)
 		if ( walk->ops && walk->ops->prepare )
 			walk->ops->prepare(walk);
 
-	/* call pollcat_poll() and optionally save the return value in poll-ret */
+	/* call pollcat_poll() if the iterator list is non-empty, otherwise sleep */
-	ret = pollcat_poll();
+	if ( pollcat_iter_head )
+		ret = pollcat_poll();
+	else
+	{
+		/* pollcat_time_value() returns milliseconds, usleep takes microseconds */
+		ret = pollcat_time_value() * 1000;
+		ret = usleep(ret);
+		ret = 0;
+	}
+
+	/* optionally save the return value in poll-ret */
 	if ( poll_ret )
 		*poll_ret = ret;
 

src/timer.c

@@ -1,7 +1,7 @@
 /** Millisecond-resolution event timers
  *
  *  This file is part of the Pollcat Library.
- *  Copyright (C) 2022 Expatria Technologies Inc.
+ *  Copyright (C) 2022,2025 Expatria Technologies Inc.
  *  Contact: Morgan Hughes <morgan@expatria.ca>
  *
  *  The Pollcat Library is free software: you can redistribute it and/or modify it under
@@ -219,11 +219,8 @@ void pollcat_timer_dispatch (void)
 
 	while ( timer_head && max-- )
 	{
-		pollcat_time_t  due = pollcat_now();
+		if ( pollcat_now() < timer_head->due )
-
+			return;
-		due -= timer_head->due;
-		if ( due > pollcat_timer_dispatch_thresh )
-            return;
 
 		// detach the head
 		struct pollcat_timer *t = timer_head;

tests/Makefile

@@ -1,7 +1,7 @@
 # Test stubs Makefile
 #
 # This file is part of the Pollcat Library.
-# Copyright (C) 2022 Expatria Technologies Inc.
+# Copyright (C) 2022,2025 Expatria Technologies Inc.
 # Contact: Morgan Hughes <morgan@expatria.ca>
 #
 # The Pollcat Library is free software: you can redistribute it and/or modify it under the
@@ -18,6 +18,10 @@
 #
 # vim:ts=4:noexpandtab
 
+# Integrators should override these
+PREFIX ?= /usr/local
+export PREFIX DESTDIR
+
 # output targets
 BINS := \
 	poll \
@@ -57,7 +61,8 @@ timer: $(TIMER_OBJS)
 
 
 install:
-	false
+	mkdir -p $(DESTDIR)$(PREFIX)/bin
+	install -m755 $(BINS) $(DESTDIR)$(PREFIX)/bin
 
 clean:
 	rm -f $(POLL_OBJS)

tests/timer.c

@@ -1,7 +1,7 @@
 /** Pollcat test stub - timers
  *
  *  This file is part of the Pollcat Library.
- *  Copyright (C) 2022 Expatria Technologies Inc.
+ *  Copyright (C) 2022,2025 Expatria Technologies Inc.
  *  Contact: Morgan Hughes <morgan@expatria.ca>
  *
  *  The Pollcat Library is free software: you can redistribute it and/or modify it under
@@ -34,12 +34,17 @@
 #include <pollcat.h>
 
 
+int opt_wrapper = 0;
+int opt_stdin   = 0;
+
+
 /** control for main loop for orderly shutdown */
 static int main_loop = 1;
 static void signal_fatal (int signum)
 {
 	fprintf(stderr, "Fatal signal %d, exit loop\n", signum);
 	main_loop = 0;
+	pollcat_loop_exit();
 }
 
 static void stop (const char *fmt, ...);
@@ -55,8 +60,9 @@ static void callback (void *arg)
 extern char *__progname;
 static void usage (void)
 {
-	printf("Usage: %s -v [-t timeout]\n"
+	printf("Usage: %s [-ws] [-t timeout]\n"
-	       "-v            Verbose (set all modules to debug, enable trace)\n"
+	       "-w            Use pollcat_poll() wrapper\n"
+	       "-s            Add stdin file descriptor to pollcat\n"
 	       "-t timeout    Timeout for poll() calls (ms)\n"
 	       "",
 	       __progname);
@@ -65,16 +71,17 @@ static void usage (void)
 
 int main (int argc, char **argv)
 {
-	int  ret = 0;
+	struct termios  tio_old;
-	short revents;
+	int             flags;
+	int             ret = 0;
 
 	// basic arguments parsing
 	int   opt;
-	while ( (opt = getopt(argc, argv, "vt:")) != -1 )
+	while ( (opt = getopt(argc, argv, "wst:")) != -1 )
 		switch ( opt )
 		{
-			case 'v':
+			case 'w': opt_wrapper = 1; break;
-				break;
+			case 's': opt_stdin = 1;   break;
 
 			case 't':
 				pollcat_time_base = atoi(optarg);
@@ -84,73 +91,92 @@ int main (int argc, char **argv)
 				usage();
 		}
 
-	pollcat_fd_add(fileno(stdin), POLLIN);
+	if ( opt_stdin )
+		pollcat_fd_add(fileno(stdin), POLLIN);
 
 	signal(SIGTERM, signal_fatal);
 	signal(SIGINT,  signal_fatal);
 
-	// reopen stdout/stderr before making stdin non-blocking
+	if ( opt_stdin )
-	char tty[256];
-	memset(tty, 0, sizeof(tty));
-	if ( readlink("/proc/self/fd/1", tty, sizeof(tty)) > 0 )
 	{
-		if ( !freopen(tty, "w", stdout) || !freopen(tty, "w", stderr) )
+		// reopen stdout/stderr before making stdin non-blocking
-			perror(tty);
+		char tty[256];
-		setbuf(stderr, NULL);
+		memset(tty, 0, sizeof(tty));
-	}
+		if ( readlink("/proc/self/fd/1", tty, sizeof(tty)) > 0 )
-
-	// set stdin nonblocking
-	int flags = fcntl(fileno(stdin), F_GETFL);
-	if ( flags < 0 )
-		stop("fcntl(0, F_GETFL)");
-	if ( fcntl(fileno(stdin), F_SETFL, flags | O_NONBLOCK) < 0 )
-		stop("fcntl(0, F_SETFL)");
-
-	// save old terminal modes and make raw
-	struct termios tio_old;
-	if ( tcgetattr(fileno(stdin), &tio_old) )
-		stop("tcgetattr(0, &tio_old)");
-
-	struct termios tio_new = tio_old;
-	tio_new.c_lflag &= ~(ECHO|ICANON);
-	if ( tcsetattr(fileno(stdin), TCSANOW, &tio_new) )
-		stop("tcsetattr(0, TCSANOW, &tio_new)");
-
-	while ( main_loop )
-	{
-		pollcat_timer_reduce_timeout();
-
-		if ( (ret = pollcat_poll()) < 0 )
 		{
-			perror("poll()");
+			if ( !freopen(tty, "w", stdout) || !freopen(tty, "w", stderr) )
-			break;
+				perror(tty);
+			setbuf(stderr, NULL);
+		}
+    
+		// set stdin nonblocking
+		if ( (flags = fcntl(fileno(stdin), F_GETFL)) < 0 )
+			stop("fcntl(0, F_GETFL)");
+		if ( fcntl(fileno(stdin), F_SETFL, flags | O_NONBLOCK) < 0 )
+			stop("fcntl(0, F_SETFL)");
+    
+		// save old terminal modes and make raw
+		if ( tcgetattr(fileno(stdin), &tio_old) )
+			stop("tcgetattr(0, &tio_old)");
+    
+		struct termios tio_new = tio_old;
+		tio_new.c_lflag &= ~(ECHO|ICANON);
+		if ( tcsetattr(fileno(stdin), TCSANOW, &tio_new) )
+			stop("tcsetattr(0, TCSANOW, &tio_new)");
+	}
+	else
+		pollcat_timer_attach(&timer, 1000, callback, NULL);
+
+	if ( opt_wrapper )
+	{
+		pollcat_dump(stderr);
+		while ( pollcat_loop(&ret) )
+			pollcat_dump(stderr);
+	}
+	else
+		while ( main_loop )
+		{
+			pollcat_timer_reduce_timeout();
+
+			pollcat_dump(stderr);
+			if ( (ret = pollcat_poll()) < 0 )
+			{
+				perror("poll()");
+				break;
+			}
+			pollcat_dump(stderr);
+
+			pollcat_timer_dispatch();
+
+			if ( !ret )
+				continue;
+
+			if ( opt_stdin )
+			{
+				short  revents = pollcat_revents(fileno(stdin));
+				assert(revents > -1);
+				if ( revents & POLLIN )
+				{
+					char buff[16];
+
+					memset(buff, 0, sizeof(buff));
+					ret = read(fileno(stdin), buff, sizeof(buff) - 1);
+					fprintf(stderr, "recv(%d): '%s'\n", ret, buff);
+
+					pollcat_timer_attach(&timer, 333, callback, NULL);
+				}
+			}
 		}
 
-		pollcat_timer_dispatch();
+	if ( opt_stdin )
+	{
+		if ( fcntl(0, F_SETFL, flags) < 0 )
+			stop("fcntl(0, F_SETFL)");
 
-		if ( !ret )
+		if ( tcsetattr(0, TCSANOW, &tio_old) )
-			continue;
+			stop("tcsetattr(0, TCSANOW, &tio_old)");
-
-		revents = pollcat_revents(fileno(stdin));
-		assert(revents > -1);
-		if ( revents & POLLIN )
-		{
-			char buff[16];
-
-			memset(buff, 0, sizeof(buff));
-			ret = read(fileno(stdin), buff, sizeof(buff) - 1);
-			fprintf(stderr, "recv(%d): '%s'\n", ret, buff);
-
-			pollcat_timer_attach(&timer, 333, callback, NULL);
-		}
 	}
 
-	if ( fcntl(0, F_SETFL, flags) < 0 )
-		stop("fcntl(0, F_SETFL)");
-
-	if ( tcsetattr(0, TCSANOW, &tio_old) )
-		stop("tcsetattr(0, TCSANOW, &tio_old)");
-
 	return 0;
 }