3 files changed, 119 insertions, 1 deletions

diff --git a/usr.sbin/pkg_install/lib/Makefile b/usr.sbin/pkg_install/lib/Makefile
index 990bfe3e19fc..0fb00b2e0700 100644
--- a/usr.sbin/pkg_install/lib/Makefile
+++ b/usr.sbin/pkg_install/lib/Makefile
@@ -1,7 +1,8 @@
 # $FreeBSD$
 
 LIB=	install
-SRCS=	file.c msg.c plist.c str.c exec.c global.c pen.c match.c
+SRCS=	file.c msg.c plist.c str.c exec.c global.c pen.c match.c \
+	deps.c
 CFLAGS+= ${DEBUG}
 NOPROFILE= yes
 NOPIC=	yes
diff --git a/usr.sbin/pkg_install/lib/deps.c b/usr.sbin/pkg_install/lib/deps.c
new file mode 100644
index 000000000000..4c06da8df1fa
--- /dev/null
+++ b/usr.sbin/pkg_install/lib/deps.c
@@ -0,0 +1,113 @@
+#ifndef lint
+static const char rcsid[] =
+  "$FreeBSD$";
+#endif
+
+/*
+ * FreeBSD install - a package for the installation and maintainance
+ * of non-core utilities.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * Maxim Sobolev
+ * 14 March 2001
+ *
+ * Routines used to do various operations with dependencies
+ * among installed packages.
+ *
+ */
+
+#include "lib.h"
+
+#include <err.h>
+#include <stdio.h>
+
+/*
+ * Sort given NULL-terminated list of installed packages (pkgs) in
+ * such a way that if package A depends on package B then after
+ * sorting A will be listed before B no matter how they were
+ * originally positioned in the list.
+ */
+int
+sortdeps(char **pkgs)
+{
+    char *tmp;
+    int i, j, loop_cnt;
+    int err_cnt = 0;
+
+    for (i = 0; pkgs[i]; i++) {
+	/*
+	 * Check to see if any other package in pkgs[i+1:] depends
+	 * on pkgs[i] and swap those two packages if so.
+	 */
+	loop_cnt = 0;
+	for (j = i + 1; pkgs[j]; j++) {
+	    if (chkifdepends(pkgs[j], pkgs[i]) == 1) {
+		/*
+		 * Try to avoid deadlock if package A depends on B which in
+		 * turn depends on C and C due to an error depends on A.
+		 * Use ugly but simple method, becase it Should Never
+		 * Happen[tm] in the real life anyway.
+		 */
+		if (loop_cnt > 4096) {
+		    warnx("dependency loop detected for package %s", pkgs[j]);
+		    err_cnt++;
+		    break;
+		}
+		loop_cnt++;
+		tmp = pkgs[i];
+		pkgs[i] = pkgs[j];
+		pkgs[j] = tmp;
+		/*
+		 * Another iteration requred to check if new pkgs[i]
+		 * itself has any packages that depend on it
+		 */
+		j = i + 1;
+	    }
+	}
+    }
+    return err_cnt;
+}
+
+/*
+ * Check to see if pkgname1 depends on pkgname2.
+ * Returns 1 if depends, 0 if not, and -1 if error occured.
+ */ 
+int
+chkifdepends(char *pkgname1, char *pkgname2)
+{
+    FILE *fp;
+    char fname[FILENAME_MAX];
+    char fbuf[FILENAME_MAX];
+    char *tmp;
+    int retval;
+
+    sprintf(fname, "%s/%s/%s",
+	    (tmp = getenv(PKG_DBDIR)) ? tmp : DEF_LOG_DIR,
+	    pkgname2, REQUIRED_BY_FNAME);
+    fp = fopen(fname, "r");
+    if (fp == NULL) {
+	/* Probably pkgname2 doesn't have any packages that depend on it */
+	return 0;
+    }
+
+    retval = 0;
+    while (fgets(fbuf, sizeof(fbuf), fp) != NULL) {
+	if (fbuf[strlen(fbuf)-1] == '\n')
+	    fbuf[strlen(fbuf)-1] = '\0';
+	if (strcmp(fbuf, pkgname1) == 0) {	/* match */
+	    retval = 1;
+	    break;
+	}
+    }
+
+    fclose(fp);
+    return retval;
+}
diff --git a/usr.sbin/pkg_install/lib/lib.h b/usr.sbin/pkg_install/lib/lib.h
index fae802da1430..0ed689984366 100644
--- a/usr.sbin/pkg_install/lib/lib.h
+++ b/usr.sbin/pkg_install/lib/lib.h
@@ -177,6 +177,10 @@ int		pkg_perform(char **);
 /* Query installed packages */
 char		**matchinstalled(match_t, char **, int *);
 
+/* Dependencies */
+int		sortdeps(char **);
+int		chkifdepends(char *, char *);
+
 /* Externs */
 extern Boolean	Verbose;
 extern Boolean	Fake;