From: John Kohl <jtkohl@mit.edu>
Date: Wed, 3 Apr 1991 09:54:31 +0000 (+0000)
Subject: add locking code
X-Git-Tag: krb5-1.0-alpha5~120
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=ffda07b8b428b85f9513df2dc1a9b6857647cbce;p=krb5.git

add locking code

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@1981 dc483132-0cff-0310-8789-dd5450dbe970
---

diff --git a/src/lib/krb5/ccache/stdio/scc_maybe.c b/src/lib/krb5/ccache/stdio/scc_maybe.c
index 39b60c9e3..8b6b3088c 100644
--- a/src/lib/krb5/ccache/stdio/scc_maybe.c
+++ b/src/lib/krb5/ccache/stdio/scc_maybe.c
@@ -18,6 +18,8 @@ static char rcsid_scc_maybe_c[] =
 
 #include "scc.h"
 #include <netinet/in.h>			/* XXX ip only? */
+#include <krb5/libos.h>
+#include <krb5/los-proto.h>
 
 krb5_error_code
 krb5_scc_close_file (id)
@@ -25,6 +27,7 @@ krb5_scc_close_file (id)
 {
      krb5_scc_data *data;
      int ret;
+     krb5_error_code retval;
 
      data = (krb5_scc_data *) id->data;
      if (data->file == (FILE *) NULL) {
@@ -43,12 +46,17 @@ krb5_scc_close_file (id)
      bzero (data->stdio_buffer, sizeof (data->stdio_buffer));
      if (ret == EOF) {
 	  int errsave = errno;
+	  (void) krb5_unlock_file(data->file, data->filename);
 	  (void) fclose (data->file);
 	  data->file = 0;
 	  return krb5_scc_interpret (errsave);
      }
+     retval = krb5_unlock_file(data->file, data->filename);
      ret = fclose (data->file);
      data->file = 0;
+     if (retval)
+	 return retval;
+     else
      return ret ? krb5_scc_interpret (errno) : 0;
 }
 
@@ -61,10 +69,12 @@ krb5_scc_open_file (id, mode)
      krb5_scc_data *data;
      FILE *f;
      char *open_flag;
+     krb5_error_code retval;
 
      data = (krb5_scc_data *) id->data;
      if (data->file) {
 	  /* Don't know what state it's in; shut down and start anew.  */
+	  (void) krb5_unlock_file(data->file, data->filename);
 	  (void) fclose (data->file);
 	  data->file = 0;
      }
@@ -88,23 +98,41 @@ krb5_scc_open_file (id, mode)
 #if 0 /* alternative, not requiring sizeof stdio_buffer == BUFSIZ */
      setvbuf(f, data->stdio_buffer, _IOFBF, sizeof (data->stdio_buffer));
 #endif
-
+     switch (mode) {
+     case SCC_OPEN_RDONLY:
+	 if (retval = krb5_lock_file(f, data->filename, KRB5_LOCKMODE_SHARED)) {
+	     (void) fclose(f);
+	     return retval;
+	 }
+	 break;
+     case SCC_OPEN_RDWR:
+     case SCC_OPEN_AND_ERASE:
+	 if (retval = krb5_lock_file(f, data->filename,
+				     KRB5_LOCKMODE_EXCLUSIVE)) {
+	     (void) fclose(f);
+	     return retval;
+	 }
+	 break;
+     }
      if (mode == SCC_OPEN_AND_ERASE) {
 	 /* write the version number */
 	 int errsave;
 
 	 if (!fwrite((char *)&scc_fvno, sizeof(scc_fvno), 1, f)) {
 	     errsave = errno;
+	     (void) krb5_unlock_file(f, data->filename);
 	     (void) fclose(f);
 	     return krb5_scc_interpret(errsave);
 	 }
      } else {
 	 /* verify a valid version number is there */
 	 if (!fread((char *)&scc_fvno, sizeof(scc_fvno), 1, f)) {
+	     (void) krb5_unlock_file(f, data->filename);
 	     (void) fclose(f);
 	     return KRB5_CCACHE_BADVNO;
 	 }
 	 if (scc_fvno != htons(KRB5_SCC_FVNO)) {
+	     (void) krb5_unlock_file(f, data->filename);
 	     (void) fclose(f);
 	     return KRB5_CCACHE_BADVNO;
 	 }