From 0edc2d5b7099d9b255e16f19689acb00c511f020 Mon Sep 17 00:00:00 2001
From: Joachim Wiberg <troglobit@gmail.com>
Date: Sat, 22 Jun 2024 12:08:24 +0200
Subject: [PATCH] execd: add support for SNN and KNN queue scripts

This change makes sure execd calls KNN style scripts before SNN,
allowing confd to post teardown jobs that are guaranteed to run
before any jobs to create new resources run.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
---
 src/execd/execd.c | 73 ++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 57 insertions(+), 16 deletions(-)

diff --git a/src/execd/execd.c b/src/execd/execd.c
index 04cd2688..d28ff5cd 100644
--- a/src/execd/execd.c
+++ b/src/execd/execd.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: ISC */
 
+#include <ctype.h>
 #include <dirent.h>
 #include <errno.h>
 #include <getopt.h>
@@ -31,7 +32,7 @@ static int   logmask = LOG_UPTO(LOG_NOTICE);
 static char  buffer[BUFSIZ];
 static char *done;
 
-static void run_job(char *path, char *file)
+static void run_job(const char *path, char *file, int archive)
 {
 	char cmd[strlen(path) + strlen(file) + 2];
 	int rc;
@@ -57,32 +58,67 @@ static void run_job(char *path, char *file)
 	}
 
 	dbg("job %s in %s done", file, path);
-	if (done)
+	if (done && archive)
 		movefile(cmd, done);
 	else
 		erase(cmd);
 }
 
-static void run_queue(char *path)
+/*
+ * Allow SNN and KNN style jobs, for inotyify_cb() we also allow
+ * a type '*' just to figure out if a job should be archived in
+ * the done directory.
+ */
+static int check(const char *name, int type, int *archive)
 {
-	struct dirent *d;
-	DIR *dir;
+	if (!name || strlen(name) < 3)
+		return -1;
 
-	dir = opendir(path);
-	if (!dir) {
-		err("opendir");
+	if (isdigit(name[1]) && isdigit(name[2])) {
+		if (type == '*')
+			type = name[0];
+
+		switch (type) {
+		case 'K':
+			*archive = 0;
+			return 0;
+		case 'S':
+			*archive = 1;
+			return 0;
+		default:
+			break;
+		}
+	}
+
+	return 1;
+}
+
+static void run_dir(const char *path, int type)
+{
+	struct dirent **namelist;
+	int archive = 0;
+	int n, i;
+
+	n = scandir(path, &namelist, NULL, alphasort);
+	if (n < 0) {
+		err("scandir %s", path);
 		return;
 	}
 
-	while ((d = readdir(dir))) {
-		dbg("Running queue %s entry %s", path, d->d_name);
-		if (d->d_name[0] == '.')
-			continue;
+	for (i = 0; i < n; i++) {
+		if (!check(namelist[i]->d_name, type, &archive))
+			run_job(path, namelist[i]->d_name, archive);
 
-		run_job(path, d->d_name);
+		free(namelist[i]);
 	}
 
-	closedir(dir);
+	free(namelist);
+}
+
+static void run_queue(char *path)
+{
+	run_dir(path, 'K');
+	run_dir(path, 'S');
 }
 
 static void signal_cb(uev_t *w, void *arg, int _)
@@ -113,10 +149,15 @@ static void inotify_cb(uev_t *w, void *arg, int _)
 
 	for (char *p = buffer; p < buffer + bytes;) {
 		struct inotify_event *event = (struct inotify_event *)p;
+		char *name = event->name;
+		int archive;
 
 		if (event->mask & (IN_CLOSE_WRITE | IN_ATTRIB | IN_MOVED_TO)) {
-			dbg("Got inotify event %s 0x%04x", event->name, event->mask);
-			run_job(arg, event->name);
+			dbg("Got inotify event %s 0x%04x", name, event->mask);
+			if (check(name, '*', &archive))
+				continue;
+
+			run_job(arg, name, archive);
 		}
 
 		p += sizeof(struct inotify_event) + event->len;