In set_name() we select the short name. Once this is correctly implemented
this will be a performance intensive operation because we need to check
that the name does not exist yet. So set_name should only be called once.
Signed-off-by: Heinrich Schuchardt <xypron.g...@gmx.de>
---
fs/fat/fat_write.c | 87 ++++++++++++++++++++++++++++------------------
1 file changed, 54 insertions(+), 33 deletions(-)
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index 7e8886791c..716b6a6627 100644
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -23,6 +23,9 @@
/* Characters that may only be used in long file names */
static const char LONG_ONLY_CHARS[] = "+,;=[]";
+/* Combined size of the name and ext fields in the directory entry */
+#define SHORT_NAME_SIZE 11
+
/**
* str2fat() - convert string to valid FAT name characters
*
@@ -68,24 +71,28 @@ static int str2fat(char *dest, char *src, int length)
*
* If a long name is needed, a short name is constructed.
*
- * @dirent: directory entry
* @filename: long file name
+ * @shortname: buffer of 11 bytes to receive chosen short name and extension
* Return: number of directory entries needed, negative on error
*/
-static int set_name(dir_entry *dirent, const char *filename)
+static int set_name(const char *filename, char *shortname)
{
char *period;
char *pos;
int period_location;
char buf[13];
int i;
+ int ret;
+ struct {
+ char name[8];
+ char ext[3];
+ } dirent;
if (!filename)
return -EIO;
- /* Initialize buffers */
- memset(dirent->name, ' ', sizeof(dirent->name));
- memset(dirent->ext, ' ', sizeof(dirent->ext));
+ /* Initialize buffer */
+ memset(&dirent, ' ', sizeof(dirent));
/* Convert filename to upper case short name */
period = strrchr(filename, '.');
@@ -95,20 +102,22 @@ static int set_name(dir_entry *dirent, const char
*filename)
period = 0;
}
if (period)
- str2fat(dirent->ext, period + 1, sizeof(dirent->ext));
- period_location = str2fat(dirent->name, pos, sizeof(dirent->name));
+ str2fat(dirent.ext, period + 1, sizeof(dirent.ext));
+ period_location = str2fat(dirent.name, pos, sizeof(dirent.name));
if (period_location < 0)
return period_location;
- if (*dirent->name == ' ')
- *dirent->name = '_';
+ if (*dirent.name == ' ')
+ *dirent.name = '_';
/* 0xe5 signals a deleted directory entry. Replace it by 0x05. */
- if (*dirent->name == 0xe5)
- *dirent->name = 0x05;
+ if (*dirent.name == 0xe5)
+ *dirent.name = 0x05;
/* If filename and short name are the same, quit. */
- sprintf(buf, "%.*s.%.3s", period_location, dirent->name, dirent->ext);
- if (!strcmp(buf, filename))
- return 1;
+ sprintf(buf, "%.*s.%.3s", period_location, dirent.name, dirent.ext);
+ if (!strcmp(buf, filename)) {
+ ret = 1;
+ goto out;
+ }
/* Construct an indexed short name */
for (i = 1; i < 0x200000; ++i) {
@@ -128,20 +137,24 @@ static int set_name(dir_entry *dirent, const char
*filename)
suffix_start = 8 - suffix_len;
if (suffix_start > period_location)
suffix_start = period_location;
- memcpy(dirent->name + suffix_start, buf, suffix_len);
- if (*dirent->ext != ' ')
+ memcpy(dirent.name + suffix_start, buf, suffix_len);
+ if (*dirent.ext != ' ')
sprintf(buf, "%.*s.%.3s", suffix_start + suffix_len,
- dirent->name, dirent->ext);
+ dirent.name, dirent.ext);
else
sprintf(buf, "%.*s", suffix_start + suffix_len,
- dirent->name);
+ dirent.name);
debug("short name: %s\n", buf);
/* TODO: Check that the short name does not exist yet. */
/* Each long name directory entry takes 13 characters. */
- return (strlen(filename) + 25) / 13;
+ ret = (strlen(filename) + 25) / 13;
+ goto out;
}
return -EIO;
+out:
+ memcpy(shortname, dirent.name, SHORT_NAME_SIZE);
+ return ret;
}
static int total_sector;
@@ -1019,18 +1032,27 @@ getit:
return 0;
}
-/*
- * Fill dir_entry
+/**
+ * fill_dentry() - fill directory entry with shortname
+ *
+ * @mydata: private filesystem parameters
+ * @dentptr: directory entry
+ * @shortname: chosen short name
+ * @start_cluster: first cluster of file
+ * @size: file size
+ * @attr: file attributes
*/
static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
- const char *filename, __u32 start_cluster, __u32 size, __u8 attr)
+ const char *shortname, __u32 start_cluster, __u32 size, __u8 attr)
{
+ memset(dentptr, 0, sizeof(*dentptr));
+
set_start_cluster(mydata, dentptr, start_cluster);
dentptr->size = cpu_to_le32(size);
dentptr->attr = attr;
- set_name(dentptr, filename);
+ memcpy(dentptr->name, shortname, SHORT_NAME_SIZE);
}
/*
@@ -1215,6 +1237,7 @@ int file_fat_write_at(const char *filename, loff_t pos,
void *buffer,
retdent->size = cpu_to_le32(pos + size);
} else {
/* Create a new file */
+ char shortname[SHORT_NAME_SIZE];
if (itr->is_root) {
/* root dir cannot have "." or ".." */
@@ -1237,21 +1260,19 @@ int file_fat_write_at(const char *filename, loff_t pos,
void *buffer,
goto exit;
}
- memset(itr->dent, 0, sizeof(*itr->dent));
-
/* Check if long name is needed */
- ret = set_name(itr->dent, filename);
+ ret = set_name(filename, shortname);
if (ret < 0)
goto exit;
if (ret > 1) {
/* Set long name entries */
- ret = fill_dir_slot(itr, filename, itr->dent->name);
+ ret = fill_dir_slot(itr, filename, shortname);
if (ret)
goto exit;
}
/* Set short name entry */
- fill_dentry(itr->fsdata, itr->dent, filename, 0, size,
+ fill_dentry(itr->fsdata, itr->dent, shortname, 0, size,
ATTR_ARCH);
retdent = itr->dent;
@@ -1484,6 +1505,8 @@ int fat_mkdir(const char *new_dirname)
ret = -EEXIST;
goto exit;
} else {
+ char shortname[SHORT_NAME_SIZE];
+
if (itr->is_root) {
/* root dir cannot have "." or ".." */
if (!strcmp(l_dirname, ".") ||
@@ -1499,21 +1522,19 @@ int fat_mkdir(const char *new_dirname)
goto exit;
}
- memset(itr->dent, 0, sizeof(*itr->dent));
-
/* Check if long name is needed */
- ret = set_name(itr->dent, dirname);
+ ret = set_name(dirname, shortname);
if (ret < 0)
goto exit;
if (ret > 1) {
/* Set long name entries */
- ret = fill_dir_slot(itr, dirname, itr->dent->name);
+ ret = fill_dir_slot(itr, dirname, shortname);
if (ret)
goto exit;
}
/* Set attribute as archive for regular file */
- fill_dentry(itr->fsdata, itr->dent, dirname, 0, 0,
+ fill_dentry(itr->fsdata, itr->dent, shortname, 0, 0,
ATTR_DIR | ATTR_ARCH);
retdent = itr->dent;
--
2.29.2
