Solaris xattr support for symlink and special files.v3.1.3qa3

Since glusterfs uses xattr for storing gfid, and xattr support for
symlinks and special files does not exist in solaris. The work around
is provided by creating hidden files under export directory on solaris
hosts only. the hidden files ares maintained in .glusterfs_xattr_inode directory,
and all xattr ops on symlink and special files are redirected to respective
inodes.

All dir entries with name starting as .glusterfs (GF_HIDDEN_PATH) will
not be shown in readdir ops.

Signed-off-by: shishir gowda <shishirng@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 2213 (Symlink fails with ENODATA)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2213

1 files changed, 227 insertions, 17 deletions

diff --git a/libglusterfs/src/compat.c b/libglusterfs/src/compat.c
index 2102216317d..914fb200683 100644
--- a/libglusterfs/src/compat.c
+++ b/libglusterfs/src/compat.c
@@ -35,9 +35,10 @@
 
 #include "compat.h"
 #include "common-utils.h"
+#include "iatt.h"
+#include "inode.h"
 
 #ifdef GF_SOLARIS_HOST_OS
-
 int 
 solaris_fsetxattr(int fd, 
 		  const char* key, 
@@ -97,6 +98,125 @@ solaris_fgetxattr(int fd,
 	return ret;
 }
 
+/* Solaris does not support xattr for symlinks and dev files. Since gfid and
+   other trusted attributes are stored as xattrs, we need to provide support for
+   them. A mapped regular file is stored in the /.glusterfs_xattr_inode of the export dir.
+   All xattr ops related to the special files are redirected to this map file.
+*/
+
+int
+make_export_path (const char *real_path, char **path)
+{
+        int     ret = -1;
+        char   *tmp = NULL;
+        char   *export_path = NULL;
+        char   *dup = NULL;
+        char   *ptr = NULL;
+        char   *freeptr = NULL;
+        uuid_t  gfid = {0, };
+        
+        export_path = GF_CALLOC (1, sizeof (char) * PATH_MAX, 0);
+        if (!export_path)
+                goto out;
+
+        dup = gf_strdup (real_path);
+        if (!dup)
+                goto out;
+
+        freeptr = dup;
+        ret = solaris_getxattr ("/", GFID_XATTR_KEY, gfid, 16);
+        /* Return value of getxattr */
+        if (ret == 16) {
+                if (!__is_root_gfid (gfid)){
+                        strcat (export_path, "/");
+                        ret = 0;
+                        goto done;
+                }
+        }
+        
+        do {
+                ptr = strtok_r (dup, "/", &tmp);
+                if (!ptr)
+                        break;
+                strcat (export_path, dup);
+                ret = solaris_getxattr (export_path, GFID_XATTR_KEY, gfid, 16);
+                if (ret == 16) {
+                        if (!__is_root_gfid (gfid)) {
+                                ret = 0;
+                                goto done;
+                        }
+                }                                
+                strcat (export_path, "/");
+                dup = tmp;
+        } while (ptr);
+
+        goto out;
+
+done:
+        if (!ret) {
+                *path = export_path;
+        }
+out:
+        if (freeptr)
+                GF_FREE (freeptr);
+        if (ret && export_path)
+                GF_FREE (export_path);
+
+        return ret;
+}
+int
+solaris_xattr_resolve_path (const char *real_path, char **path)
+{
+        int                    ret  = -1;
+        char                   *export_path = NULL;
+        char                   xattr_path[PATH_MAX] = {0, };
+        struct stat            lstatbuf = {0, };
+        struct iatt            stbuf = {0, };
+        struct stat            statbuf = {0, };
+
+        ret = lstat (real_path, &lstatbuf);
+        if (ret != 0 )
+                return ret;
+        iatt_from_stat (&stbuf, &lstatbuf);
+        if (IA_ISREG(stbuf.ia_type) || IA_ISDIR(stbuf.ia_type))
+                return -1;
+
+        ret = make_export_path (real_path, &export_path);
+        if (!ret && export_path) {
+                strcat (export_path, "/"GF_SOLARIS_XATTR_DIR);
+                if (lstat (export_path, &statbuf)) {
+                        ret = mkdir (export_path, 0777);
+                        if (ret && (errno != EEXIST)) {
+                        	gf_log ("", GF_LOG_DEBUG, "mkdir failed," 
+                                        " errno: %d", errno);
+                        	goto out;
+                        }
+                }
+                
+                snprintf(xattr_path, PATH_MAX, "%s%s%lu", export_path,
+                        "/", stbuf.ia_ino);
+
+		ret = lstat (xattr_path, &statbuf);
+
+		if (ret) {
+			ret = mknod (xattr_path, S_IFREG|O_WRONLY, 0);
+			if (ret && (errno != EEXIST)) {
+				gf_log ("", GF_LOG_WARNING,"Failed to create "
+					"mapped file %s, error %d", xattr_path,
+                                         errno);
+				goto out;
+			}					
+		}
+                *path = gf_strdup (xattr_path);
+        }
+out:
+        if (export_path)
+                GF_FREE (export_path);
+        if (*path)
+                return 0;
+        else
+                return -1;
+}
 
 int 
 solaris_setxattr(const char *path, 
@@ -107,21 +227,30 @@ solaris_setxattr(const char *path,
 {
 	int attrfd = -1;
 	int ret = 0;
-	
-	attrfd = attropen (path, key, flags|O_CREAT|O_WRONLY, 0777);
+        char *mapped_path = NULL;
+
+        ret = solaris_xattr_resolve_path (path, &mapped_path);
+        if (!ret) {
+                attrfd = attropen (mapped_path,  key, flags|O_CREAT|O_WRONLY,
+                                   0777);
+        } else {
+                attrfd = attropen (path, key, flags|O_CREAT|O_WRONLY, 0777);
+        }
 	if (attrfd >= 0) {
 		ftruncate (attrfd, 0);
 		ret = write (attrfd, value, size);
 		close (attrfd);
+                ret = 0;
 	} else {
 		if (errno != ENOENT)
 			gf_log ("libglusterfs", GF_LOG_ERROR, 
 				"Couldn't set extended attribute for %s (%d)", 
 				path, errno);
-		return -1;
+		ret = -1;
 	}
-	
-	return 0;
+        if (mapped_path)
+                GF_FREE (mapped_path);	
+	return ret;
 }
 
 
@@ -135,8 +264,15 @@ solaris_listxattr(const char *path,
 	DIR *dirptr = NULL;
 	struct dirent *dent = NULL;
 	int newfd = -1;
-	
-	attrdirfd = attropen (path, ".", O_RDONLY, 0);
+        char *mapped_path = NULL;
+        int ret = -1;
+
+        ret = solaris_xattr_resolve_path (path, &mapped_path);
+        if (!ret) {
+                attrdirfd = attropen (mapped_path, ".", O_RDONLY, 0);
+        } else {	
+                attrdirfd = attropen (path, ".", O_RDONLY, 0);
+        }
 	if (attrdirfd >= 0) {
 		newfd = dup(attrdirfd);
 		dirptr = fdopendir(newfd);
@@ -167,14 +303,19 @@ solaris_listxattr(const char *path,
 			
 			if (closedir(dirptr) == -1) {
 				close (attrdirfd);
-				return -1;
+				len = -1;
+                                goto out;
 			}
 		} else {
 			close (attrdirfd);
-			return -1;
+			len = -1;
+                        goto out;
 		}
 		close (attrdirfd);
 	}
+out:
+        if (mapped_path)
+                GF_FREE (mapped_path);
 	return len;
 }
 
@@ -238,17 +379,28 @@ solaris_removexattr(const char *path,
 		    const char* key)
 {
 	int ret = -1;
-	int attrfd = attropen (path, ".", O_RDONLY, 0);
+        int attrfd = -1;
+        char *mapped_path = NULL;
+
+        ret = solaris_xattr_resolve_path (path, &mapped_path);
+        if (!ret) {
+                attrfd = attropen (mapped_path, ".", O_RDONLY, 0);
+        } else {
+                attrfd = attropen (path, ".", O_RDONLY, 0);
+        }
 	if (attrfd >= 0) {
 		ret = unlinkat (attrfd, key, 0);
 		close (attrfd);
 	} else {
 		if (errno == ENOENT)
 			errno = ENODATA;
-		return -1;
+		ret = -1;
 	}
-	
-	return ret;
+
+        if (mapped_path)
+                GF_FREE (mapped_path);
+
+        return ret;
 }
 
 int 
@@ -259,8 +411,15 @@ solaris_getxattr(const char *path,
 {
 	int attrfd = -1;
 	int ret = 0;
-	
-	attrfd = attropen (path, key, O_RDONLY, 0);
+        char *mapped_path = NULL;
+
+        ret = solaris_xattr_resolve_path (path, &mapped_path);
+        if (!ret) {
+                attrfd = attropen (mapped_path, key, O_RDONLY, 0);
+        } else { 
+                attrfd = attropen (path, key, O_RDONLY, 0);
+        }
+
 	if (attrfd >= 0) {
 		if (size == 0) {
 			struct stat buf;
@@ -277,8 +436,10 @@ solaris_getxattr(const char *path,
 			gf_log ("libglusterfs", GF_LOG_DEBUG, 
 				"Couldn't read extended attribute for the file %s (%d)", 
 				path, errno);
-		return -1;
+		ret = -1;
 	}
+        if (mapped_path)
+                GF_FREE (mapped_path);
 	return ret;
 }
 
@@ -326,6 +487,55 @@ asprintf (char **buf, const char *fmt, ...)
   return status;  
 }
 
+int solaris_unlink (const char *path)
+{
+        char *mapped_path = NULL;
+        struct stat	stbuf = {0, };
+        int ret = -1;
+
+        ret = solaris_xattr_resolve_path (path, &mapped_path);
+	
+
+        if (!ret && mapped_path) {
+		if (lstat(path, &stbuf)) {
+			gf_log ("",GF_LOG_WARNING, "Stat failed on mapped"
+				" file %s with error %d", mapped_path, errno);
+			goto out;
+		}
+                if (stbuf.st_nlink == 1) {
+			 if(remove (mapped_path))
+                        	gf_log ("", GF_LOG_WARNING, "Failed to remove mapped "
+					"file %s. Errno %d", mapped_path, errno);
+		}
+
+	}
+
+out:
+	if (mapped_path)
+		GF_FREE (mapped_path);
+
+	return  unlink (path);
+}
+
+int
+solaris_rename (const char *old_path, const char *new_path)
+{
+        char *mapped_path = NULL;
+        int ret = -1;
+
+        ret = solaris_xattr_resolve_path (new_path, &mapped_path);
+
+
+        if (!ret && mapped_path) {
+                if (!remove (mapped_path))
+                        gf_log ("", GF_LOG_WARNING, "Failed to remove mapped "
+                                "file %s. Errno %d", mapped_path, errno);
+        	GF_FREE (mapped_path);
+	}
+
+        return rename(old_path, new_path);
+
+}
 #endif /* GF_SOLARIS_HOST_OS */
 
 #ifndef HAVE_STRNLEN