Replace FAM/Gamin with inotify

1 files changed, 201 insertions, 0 deletions

diff --git a/maildir/maildirwatchprog.c b/maildir/maildirwatchprog.c
new file mode 100644
index 0000000..f169da8
--- /dev/null
+++ b/maildir/maildirwatchprog.c
@@ -0,0 +1,201 @@
+/*
+** Copyright 2021 Double Precision, Inc.
+** See COPYING for distribution information.
+*/
+
+
+#if	HAVE_CONFIG_H
+#include	"config.h"
+#endif
+#include	<stdio.h>
+#include	<string.h>
+#include	<stdlib.h>
+#include	<errno.h>
+#include	<sys/types.h>
+#if	HAVE_SYS_WAIT_H
+#include	<sys/wait.h>
+#endif
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <poll.h>
+#include	"maildirwatch.h"
+
+static void usage()
+{
+	printf("Usage: maildirwatch maildir program arguments...\n");
+	exit(1);
+}
+
+static int forkexec(int argc, char **argv)
+{
+	pid_t p=fork();
+	int s;
+
+	if (p < 0)
+	{
+		perror("fork");
+		return  0;
+	}
+
+	if (p == 0)
+	{
+		char **argvptr=malloc(sizeof(char *)*(argc+1));
+		int n;
+
+		if (!argvptr)
+		{
+			perror("malloc");
+			exit(1);
+		}
+
+		for (n=0; n<argc; ++n)
+			argvptr[n]=argv[n];
+		argvptr[n]=0;
+		execvp(argvptr[0], argvptr);
+		perror(argv[0]);
+		exit(1);
+	}
+
+	if (waitpid(p, &s, 0) != p)
+		return 0;
+
+	if (!WIFEXITED(s))
+	{
+		if (WIFSIGNALED(s))
+			printf("-%d\n", (int)WTERMSIG(s));
+		else
+			printf("-0\n");
+		return 0;
+	}
+
+	if (WEXITSTATUS(s))
+	{
+		printf("%d\n", (int)WEXITSTATUS(s));
+		return 0;
+	}
+	return 1;
+}
+
+int main(int argc, char *argv[])
+{
+	struct maildirwatch *watch;
+	struct maildirwatch_contents mc;
+	int fdret;
+	int rc;
+
+	if (argc < 3)
+		usage();
+
+	/*
+	** Call maildirwatch_alloc, then maildirwatch_start.
+	*/
+
+	watch=maildirwatch_alloc(argv[1]);
+
+	if (maildirwatch_start(watch, &mc) < 0)
+	{
+		perror(argv[1]);
+		exit(1);
+	}
+
+	/*
+	** poll() the returned file descriptor as long as
+	** maildirwatch_started returns 0.
+	*/
+
+	while ((rc=maildirwatch_started(&mc, &fdret)) == 0)
+	{
+		struct pollfd pfd;
+
+		pfd.fd=fdret;
+		pfd.events=POLLIN;
+
+		if (poll(&pfd, 1, -1) < 0)
+		{
+			perror(argv[1]);
+			exit(1);
+		}
+	}
+
+	if (rc < 0)
+	{
+		perror(argv[1]);
+		exit(1);
+	}
+
+	/*
+	** The maildir is now being monitored.
+	*/
+
+	while (forkexec(argc-2, argv+2))
+	{
+		int was_changed=0;
+
+		while (1)
+		{
+			int changed;
+			int timeout;
+
+			/*
+			** maildirwatch_check() checks if the maildir has
+			** been changed.
+			*/
+			int rc=maildirwatch_check(&mc, &changed, &fdret,
+						  &timeout);
+
+
+			if (rc < 0)
+			{
+				perror(argv[1]);
+				exit(1);
+			}
+
+			/*
+			** If it's changed, you can call it again.
+			** maildirwatch_check() does not block.
+			*/
+			if (changed)
+			{
+				was_changed=1;
+				continue;
+			}
+
+			if (was_changed)
+				break;
+
+			/*
+			** If it's not changed, poll() for the number of
+			** seconds specified by the timeout.
+			**
+			** In polling mode fdret is 0, so sleep, then
+			** check the maildir manually.
+			*/
+
+			if (fdret < 0)
+			{
+				sleep(timeout);
+				continue;
+			}
+
+			struct pollfd pfd;
+
+			pfd.fd=fdret;
+			pfd.events=POLLIN;
+
+			if (poll(&pfd, 1, timeout * 1000) < 0)
+			{
+				perror("poll");
+				exit(1);
+			}
+		}
+	}
+
+	/*
+	** Cleanup.
+	*/
+
+	maildirwatch_end(&mc);
+	maildirwatch_free(watch);
+	return (0);
+}