- don't use env variables for passwords and usernames (yeah!)

- added a shared variable area based on a unlinked open file, and
  implement a general get/set interface to it
- cache hostname lookups and master ip lookups in shared variable area
(This used to be commit 279cbe69efd75450113d2da0da5e67b29f3702b1)

1 files changed, 179 insertions, 0 deletions

diff --git a/source3/smbwrapper/shared.c b/source3/smbwrapper/shared.c
new file mode 100644
index 0000000000..4637248dce
--- /dev/null
+++ b/source3/smbwrapper/shared.c
@@ -0,0 +1,179 @@
+/* 
+   Unix SMB/Netbios implementation.
+   Version 2.0
+   SMB wrapper functions - shared variables
+   Copyright (C) Andrew Tridgell 1998
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+extern int DEBUGLEVEL;
+
+static int shared_fd;
+static char *variables;
+static int shared_size;
+
+/***************************************************** 
+setup the shared area 
+*******************************************************/
+void smbw_setup_shared(void)
+{
+	int fd;
+	pstring s, name;
+
+	slprintf(s,sizeof(s)-1, "%s/msg.XXXXXX",tmpdir());
+
+	fstrcpy(name,(char *)mktemp(s));
+
+	/* note zero permissions! don't change this */
+	fd = open(name,O_RDWR|O_CREAT|O_TRUNC|O_EXCL,0); 
+	if (fd == -1) goto failed;
+
+	shared_fd = set_maxfiles(SMBW_MAX_OPEN);
+	
+	while (shared_fd && dup2(fd, shared_fd) != shared_fd) shared_fd--;
+
+	if (shared_fd == 0) goto failed;
+
+	close(fd);
+
+	DEBUG(4,("created shared_fd=%d\n", shared_fd));
+
+	slprintf(s,sizeof(s)-1,"%d", shared_fd);
+
+	setenv("SMBW_HANDLE", s, 1);
+
+	return;
+
+ failed:
+	perror("Failed to setup shared variable area ");
+	exit(1);
+}
+
+
+/***************************************************** 
+lock the shared variable area
+*******************************************************/
+static void lockit(void)
+{
+	if (shared_fd == 0) {
+		char *p = getenv("SMBW_HANDLE");
+		if (!p) {
+			DEBUG(0,("ERROR: can't get smbw shared handle\n"));
+			exit(1);
+		}
+		shared_fd = atoi(p);
+	}
+	if (fcntl_lock(shared_fd,SMB_F_SETLKW,0,1,F_WRLCK)==False) {
+		DEBUG(0,("ERROR: can't get smbw shared lock\n"));
+		exit(1);
+	}
+}
+
+/***************************************************** 
+unlock the shared variable area
+*******************************************************/
+static void unlockit(void)
+{
+	fcntl_lock(shared_fd,SMB_F_SETLK,0,1,F_UNLCK);
+}
+
+
+/***************************************************** 
+get a variable from the shared area
+*******************************************************/
+char *smbw_getshared(const char *name)
+{
+	int i;
+	struct stat st;
+
+	lockit();
+
+	/* maybe the area has changed */
+	if (fstat(shared_fd, &st)) goto failed;
+
+	if (st.st_size != shared_size) {
+		variables = (char *)Realloc(variables, st.st_size);
+		if (!variables) goto failed;
+		shared_size = st.st_size;
+		lseek(shared_fd, 0, SEEK_SET);
+		if (read(shared_fd, variables, shared_size) != shared_size) {
+			goto failed;
+		}
+	}
+
+	unlockit();
+
+	i=0;
+	while (i < shared_size) {
+		int len;
+		char *n, *v;
+
+		n = &variables[i];
+		i += strlen(n)+1;
+		v = &variables[i];
+		i += strlen(v)+1;
+
+		if (strcmp(name,n)) {
+			continue;
+		}
+		return v;
+	}
+
+	return NULL;
+
+ failed:
+	DEBUG(0,("smbw: shared variables corrupt (%s)\n", strerror(errno)));
+	exit(1);
+}
+
+
+
+/***************************************************** 
+set a variable in the shared area
+*******************************************************/
+void smbw_setshared(const char *name, const char *val)
+{
+	int len;
+
+	/* we don't allow variable overwrite */
+	if (smbw_getshared(name)) return;
+
+	lockit();
+
+	len = strlen(name) + strlen(val) + 2;
+
+	variables = (char *)Realloc(variables, shared_size + len);
+
+	if (!variables) {
+		DEBUG(0,("out of memory in smbw_setshared\n"));
+		exit(1);
+	}
+
+	pstrcpy(&variables[shared_size], name);
+	shared_size += strlen(name)+1;
+	pstrcpy(&variables[shared_size], val);
+	shared_size += strlen(val)+1;
+
+	lseek(shared_fd, 0, SEEK_SET);
+	if (write(shared_fd, variables, shared_size) != shared_size) {
+		DEBUG(0,("smbw_setshared failed (%s)\n", strerror(errno)));
+		exit(1);
+	}
+
+	unlockit();
+}