MonetDB: Jan2014 - Avoid time-of-check time-of-use race by just ...

[Sjoerd Mullender]

Changeset: a5da985a453d for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=a5da985a453d
Modified Files:
        tools/merovingian/utils/database.c
Branch: Jan2014
Log Message:

Avoid time-of-check time-of-use race by just trying and checking errors.


diffs (76 lines):

diff --git a/tools/merovingian/utils/database.c 
b/tools/merovingian/utils/database.c
--- a/tools/merovingian/utils/database.c
+++ b/tools/merovingian/utils/database.c
@@ -161,10 +161,9 @@ char* db_create(char* dbname) {
 }
 
 /* recursive helper function to delete a directory */
-static char* deletedir(char *dir) {
+static char* deletedir(const char *dir) {
        DIR *d;
        struct dirent *e;
-       struct stat s;
        char buf[8192];
        char path[4096];
 
@@ -174,45 +173,33 @@ static char* deletedir(char *dir) {
                 * probably already deleted */
                if (errno == ENOENT)
                        return(NULL);
+               if (errno == ENOTDIR) {
+                       if (unlink(dir) == -1 && errno != ENOENT) {
+                               snprintf(buf, sizeof(buf),
+                                        "unable to unlink file %s: %s",
+                                        dir, strerror(errno));
+                               return(strdup(buf));
+                       }
+                       return NULL;
+               }
                snprintf(buf, sizeof(buf), "unable to open dir %s: %s",
                                dir, strerror(errno));
                return(strdup(buf));
        }
        while ((e = readdir(d)) != NULL) {
-               snprintf(path, sizeof(path), "%s/%s", dir, e->d_name);
-               if (stat(path, &s) == -1) {
-                       snprintf(buf, sizeof(buf), "unable to stat file %s: %s",
-                                       path, strerror(errno));
-                       closedir(d);
-                       return(strdup(buf));
-               }
-
-               if (S_ISREG(s.st_mode) || S_ISLNK(s.st_mode) || 
S_ISSOCK(s.st_mode)) {
-                       if (unlink(path) == -1) {
-                               snprintf(buf, sizeof(buf), "unable to unlink 
file %s: %s",
-                                               path, strerror(errno));
-                               closedir(d);
-                               return(strdup(buf));
-                       }
-               } else if (S_ISDIR(s.st_mode)) {
+               /* ignore . and .. */
+               if (strcmp(e->d_name, ".") != 0 &&
+                   strcmp(e->d_name, "..") != 0) {
                        char* er;
-                       /* recurse, ignore . and .. */
-                       if (strcmp(e->d_name, ".") != 0 &&
-                                       strcmp(e->d_name, "..") != 0 &&
-                                       (er = deletedir(path)) != NULL)
-                       {
+                       snprintf(path, sizeof(path), "%s/%s", dir, e->d_name);
+                       if ((er = deletedir(path)) != NULL) {
                                closedir(d);
                                return(er);
                        }
-               } else {
-                       /* fifos, block, char devices etc, we don't do */
-                       snprintf(buf, sizeof(buf), "not a regular file: %s", 
path);
-                       closedir(d);
-                       return(strdup(buf));
                }
        }
        closedir(d);
-       if (rmdir(dir) == -1) {
+       if (rmdir(dir) == -1 && errno != ENOENT) {
                snprintf(buf, sizeof(buf), "unable to remove directory %s: %s",
                                dir, strerror(errno));
                return(strdup(buf));
_______________________________________________
checkin-list mailing list
checkin-list@monetdb.org
https://www.monetdb.org/mailman/listinfo/checkin-list