From: Alan Cox <alan@linux.intel.com>
Date: Tue, 26 May 2015 23:06:58 +0000 (+0100)
Subject: opendir/readdir/closedir: partial rewrite, fix errors, block cache
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=337be789e3bdce8c8c028031a1a31eccd9f5248d;p=FUZIX.git

opendir/readdir/closedir: partial rewrite, fix errors, block cache

We now pull a sector at a time and hand it out an entry at a time. This makes
life a lot quicker. In addition we now use one allocation not two and the
code correctly handles the corner case of the directory being fd 0
---

diff --git a/Library/include/dirent.h b/Library/include/dirent.h
index 707a5c28..bfb9e7ea 100644
--- a/Library/include/dirent.h
+++ b/Library/include/dirent.h
@@ -4,8 +4,6 @@
 #include <types.h>
 #endif
 
-/* It's 14 for the kernel as it stands but may move to 30 so build
-   that into userspace */
 
 #define MAXNAMLEN	30
 
@@ -17,6 +15,7 @@ typedef struct {
 	struct dirent *dd_buf;	/* -> directory buffer */
 } DIR;				/* stream data from opendir() */
 
+
 typedef int (*__dir_select_fn_t) __P ((struct dirent *));
 
 typedef int (*__dir_compar_fn_t) __P ((struct dirent **, struct dirent **));
@@ -28,12 +27,21 @@ struct dirent {
 	char		d_name[31];
 };
 
-/* Internal version */
+/* Kernel directory format off disk */
 struct __dirent {
-	int 		d_ino;
+	ino_t		d_ino;
 	char		d_name[30];
 };
 
+/* Internal directory structure */
+struct _dir {
+	DIR d;
+	struct dirent de;
+	uint8_t buf[512];
+	uint8_t next;
+	uint8_t last;
+};
+
 extern DIR *opendir __P ((char *__name));
 extern int closedir __P ((DIR * __dirp));
 extern struct dirent *readdir __P ((DIR * __dirp));
diff --git a/Library/libs/closedir.c b/Library/libs/closedir.c
index 98ae649a..efcf3777 100644
--- a/Library/libs/closedir.c
+++ b/Library/libs/closedir.c
@@ -1,4 +1,4 @@
-/* close.c      closedir implementation
+/* closedir.c      closedir implementation
  *
  */
 #include <unistd.h>
@@ -9,16 +9,15 @@
 #include <fcntl.h>
 #include <string.h>
 
-int closedir(DIR * dir)
+int closedir(DIR * dirp)
 {
-	if (dir == NULL || dir->dd_buf == NULL || dir->dd_fd == 0) {
+	struct _dir *dir = (struct _dir *)dirp;
+	if (dir == NULL || dir->d.dd_fd == -1) {
 		errno = EFAULT;
 		return -1;
 	}
-	close(dir->dd_fd);
-	free(dir->dd_buf);
-	dir->dd_fd = 0;
-	dir->dd_buf = NULL;
+	close(dir->d.dd_fd);
+	dir->d.dd_fd = -1;
 	free(dir);
 	return 0;
 }
diff --git a/Library/libs/opendir.c b/Library/libs/opendir.c
index 3c9f8c57..30e06ff7 100644
--- a/Library/libs/opendir.c
+++ b/Library/libs/opendir.c
@@ -9,27 +9,22 @@
 DIR *opendir(char *path)
 {
 	struct stat statbuf;
-	register DIR *dir;
+	struct _dir *dir;
 
 	if (stat(path, &statbuf) != 0)
-		goto Err;
+		return NULL;
+
 	if ((statbuf.st_mode & S_IFDIR) == 0) {
 		errno = ENOTDIR;
-		goto Err;
-	}
-	if ((dir = (DIR *) calloc(1, sizeof(DIR))) == NULL) {
-		errno = ENOMEM;
-		goto Err;
+		return NULL;
 	}
-	if ((dir->dd_buf = calloc(1, sizeof(struct dirent))) == NULL) {
-		free(dir);
+	if ((dir = calloc(1, sizeof(struct _dir))) == NULL) {
 		errno = ENOMEM;
-		goto Err;
+		return NULL;
 	}
-	if ((dir->dd_fd = open(path, O_RDONLY | O_CLOEXEC)) < 0) {
-		free(dir->dd_buf);
+	if ((dir->d.dd_fd = open(path, O_RDONLY | O_CLOEXEC)) < 0) {
 		free(dir);
-	      Err:return NULL;
+		return NULL;
 	}
-	return dir;
+	return (DIR *)dir;
 }
diff --git a/Library/libs/readdir.c b/Library/libs/readdir.c
index 44f0afe2..a25c2737 100644
--- a/Library/libs/readdir.c
+++ b/Library/libs/readdir.c
@@ -9,31 +9,42 @@
 #include <fcntl.h>
 #include <string.h>
 
-struct dirent *readdir(DIR * dir)
+static struct __dirent *dnext(struct _dir *dir)
 {
-	struct __dirent direntry;
+        if (dir->next == dir->last) {
+                int l = read(dir->d.dd_fd, dir->buf, sizeof(dir->buf));
+                if (l == 0)
+                        return NULL;
+                l /= 32;
+                dir->last = l;
+                dir->next = 0;
+        }
+        return (struct __dirent *)(dir->buf + 32 * dir->next++);
+}
+
+struct dirent *readdir(DIR * dirp)
+{
+        struct _dir *dir = (struct _dir *)dirp;
+	struct __dirent *direntry;
 	register struct dirent *buf;
 	int len;
 
-	if (dir == NULL || dir->dd_buf == NULL || dir->dd_fd == 0) {
+	if (dir == NULL || dir->d.dd_fd == -1) {
 		errno = EFAULT;
 		return NULL;
-	}
-	direntry.d_name[0] = 0;
-	while (direntry.d_name[0] == 0) {
-	        len = _getdirent(dir->dd_fd, &direntry, sizeof(direntry));
-	        if (len > sizeof(direntry)) {
-			errno = ERANGE;
-			return NULL; 
-		}
-		if (len == 0)
+        }
+
+	do {
+	        direntry = dnext(dir);
+		if (direntry == NULL)
 			return NULL;
-	}
-	buf = dir->dd_buf;
-	buf->d_ino = direntry.d_ino;
+	} while (direntry->d_name[0] == 0);
+
+	buf = &dir->de;
+	buf->d_ino = direntry->d_ino;
 	buf->d_off = -1;	/* FIXME */
-	buf->d_reclen = len + 1;
-	strncpy(buf->d_name, (char *) direntry.d_name, len - 2);
-	buf->d_name[len - 2] = 0;
+	buf->d_reclen = 33;
+	strncpy(buf->d_name, (char *) direntry->d_name, 31);
+	buf->d_name[30] = 0;
 	return buf;
 }